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The Tweed Profile Published by The Charles H. Tweed International Foundation For Orthodontic Research and Education Volume XI 2012 Contents 2 A Look At A Particular Type of Class II Malocclusion — Herb Klontz and Jim Vaden Oklahoma City, Oklahoma and Cookeville, Tennessee 14 A New Twist on 3rd Order — Bob Stoner Indianapolis, Indiana 18 The Human Face…Our Past…Present…Future? — Dennis Ward Avon Lake, Ohio 21 Why the Single Bracket? — Elie Amm Jbeil (Byblos), Lebanon 23 Class III Correction and Surgical Orthontics: the Good, the Bad, Ugly — Mike Behnan Clinton Township, Michigan 27 Cephalometrics Revisited — Hiroshi Maruo, Claudio Vinícius Sabatoski, Orlando Tanaka, Armando Yukio Saga, Ivan Toshio Maruo Brazil 36 Case Report: A Full Step Class II Patient Revisisted 27 Years Posttreatment — Vance Dykhouse Blue Springs, Missouri 40 Case Report: Vertical Control in a High Angle Patient Who Needed Rapid Maxillary Expansion (RME) — Mauricio Escanola Tepic, Nayarit / Mexico 43 Case Report: Treatment of a High Angle Adolescent Patient — Kortne Frederick Hou Tukwila, Washington 45 Case Report: Correction of a Severe Class II Division I Malocclusion in an Adolescent Patient — Jack Hou Tukwila, Washington and the A Look At A Particular Type of Class II Malocclusion Herb Klontz Oklahoma City, Oklahoma Jim Vaden Cookeville, Tennessee There are many variations of the Class II malocclusion. It has been studied; its treatment protocols have been debated; and the ramifications of its various treatment solutions have been referenced in our literature for many, many years. The purpose of this short paper is to offer a brief discussion of the types of Class II malocclusions that are generally best treatment planned for the removal of maxillary first premolars and mandibular second premolars. What we will attempt with this short article is to give the reader an overview of some of the things to consider when treatment planning a Class II malocclusion that would be well treated with the removal of maxillary first/mandibular second premolars. Three case reports will be used to illustrate our thoughts on the Class II that is best corrected with this extraction pattern. The Face When the treatment plan is devised, the first area which must be studied is the face. Is the face a consideration when an extraction pattern is considered? Absolutely! Most patients who are treatment planned for this extraction protocol have a facial pattern that almost has balance, or the face may well exhibit balance and harmony. The Z-angle of most of these patients will range from the mid 70’s to the high 50’s – low 60’s. A patient with a Z-angle of 45 should probably not be treatment planned for maxillary first premolars and mandibular second premolars because this patient needs significant mandibular incisor uprighting. The face plays a critical part in the diagnosis and in the treatment plan. But the extraction pattern cannot be based solely upon facial esthetics. Other areas must be considered. The Skeletal Pattern Many patients who have a moderate to low vertical dimension along with a Class II dentition can be well managed when maxillary first/mandibular second premolars are removed. It would be very difficult to remove these teeth and successfully correct the malocclusion for a patient who has a very high mandibular plane angle because this patient generally needs more mandibular incisor uprighting than the clinician is going to achieve with mandibular second premolar extractions. Conversely, if the FMA is very low, mandibular incisors should be left in their pretreatment positions and mandibular second premolar extractions are a good choice if the Class II dentition is to be corrected. Therefore, most patients who are treated with the extraction of maxillary first/mandibular seconds premolars have a moderate to low mandibular plane angle. The Dentition If the mandibular incisors in the Class II patient are in good position over basal bone, and if there is not a lot of crowding of these teeth, maxillary first/mandibular second premolar extractions should always be considered. This extraction pattern will allow the clinician to maintain mandibular incisor position and protract the mandibular posterior teeth for molar correction. If there is significant mandibular anterior crowding, the patient is generally not a candidate for this extraction pattern. The patient should present with moderate to minor crowding and a Class II dental relationship for this extraction sequence to be considered. In summary, there is no single factor that can be used to unequivocally place a patient into the maxillary first premolar/mandibular second premolar extraction category. Yet, when the interrelationships of the face, the skeletal pattern, and the dentition are considered, it becomes pretty evident as to which teeth should be extracted. The records of the three patients that follow will, hopefully, give a very good picture of the types of patients who are most amenable to treatment with this extraction pattern. The authors have carefully selected these patients because each one had a different set of problems that were sucessfully corrected. 2 Case #1 – Henry Griffey Up until a few years ago, the records of this patient were shown at every Tweed Study Course. Henry is a classic maxillary first premolar and mandibular second premolar extraction patient. His records are being presented in this article because his malocclusion exemplifies all of the characteristics of a malocclusion that needs this type of treatment plan. His face is reasonably balanced and harmonious. If he had no dental problems, the orthodontist would not treat him. Facial esthetics and the desire to change facial esthetics is not the reason for treating Henry Griffey. Henry’s casts slow a marked Class II relationship of the teeth with minor mandibular anterior crowding and moderate maxillary crowding. The overbite is not significant. Overjet, because of the maxillary crowding, is not significant. The cephalometric radiograph and its tracing exhibit a mandibular dentition that is upright with an IMPA of 86°. FMIA is 65° and the Z-angle is 71°. The craniofacial difficulty is only 20. Total difficulty is 54. A low difficulty like this is relatively normal for patients who are treatment planned with the removal of maxillary first premolars/mandibular second premolars. 3 The posttreatment face, when compared to the pretreatment face, shows a bit more softness, minor upper lip retraction, and a small amount of mandibular projection when the overall face is viewed. The pretreatment/posttreatment casts exhibit correction of the Class II dental occlusion, anchorage preparation in the mandibular arch, and a curve of occlusion in the maxillary arch. Note that there is spacing between the maxillary first molars and second molars which is characteristic of bulbous loop treatment. The pretreatment/posttreatment cephalograms exhibit control of the mandibular incisors, anchorage preparation, and third molars that will need to be extracted. (Normally, third molar position is not a treatment problem with these patients because the mandibular first and second molars are protracted.) The pretreatment/posttreatment cephalometric tracings and values exhibit maintenance of mandibular incisor position, control of the vertical dimension, and a Z-angle increase from 71° to 77°. Again, many of these patients do not need much of a facial change. The pretreatment/ posttreatment superimpostions exhibit downward and forward mandibular change when compared to the maxilla, more chin projection, and control of the dentition as the patient was being treated. 4 5 Case #2 – Dara Smith The facial esthetics of this patient, like the esthetics of Henry Griffey, would not warrant treatment unless the patient had a malocclusion. The chin is a bit recessive, but this small amount of imbalance is not unsightly. The casts exhibit a Class II dental relationship on the patient’s right side and a mesially inclined mandibular first molar on the patient’s left side. There is a slight amount of maxillary anterior crowding. Overbite and overjet are not excessive. When one looks at the panoramic radiograph, it is evident that the mandibular left second premolar has no space. The cephalogram and its tracing reflect a very low mandibular plane angle of 13°, an ANB of 5°, a Z-angle of 78° and an IMPA of 104°. The total difficulty is 85. Craniofacial difficulty is 60. This difficulty is a bit more than one normally sees on these patients and it is entirely due to the low Frankfort mandibular plane angle. Treatment choices were to expand the dentition or to remove teeth. In many instances, the treatment plan is based upon how to preserve the position of the mandibular anterior teeth. Dara’s mandibular incisors are inclined to 104° and it is not prudent to increase that inclination. Extraction was the only choice. Maxillary first premolars and mandibular second premolars were extracted. 6 The pretreatment/posttreatment facial photographs illustrate control of the upper lip and its relationship to the nose. There is some projection of the mandible when it is compared to the rest of the face. The pretreatment/posttreatment casts exhibit correction of the Class II dental problem and preservation of arch form and arch width. The pretreatment/posttreatment cephalograms illustrate control of mandibular incisor position even though mandibular teeth were removed. When one compares the pretreatment/posttreatment tracings, it is evident that the anterior part of the dentition did not change appreciably. The FMIA increased to 69° while mandibular incisors uprighted only 3°. Extraction of the mandibular second premolars allowed maintenance of mandibular incisor position and protraction of mandibular molars for this low angle patient. The Z-angle increased from 78° to 84°. Superimpositions reflect control of the anterior part of the dentition and protraction of the mandibular molars. There was a significant amount of mandibular growth as is evidenced by the chin projection. 7 Records were made seven years after the cessation of active retention. Note the pleasing balance and harmony of the lower face. The casts reflect aligned teeth and a well interdigitated occlusion. There has been very little change in the position of the mandibular anterior teeth. Third molars are in the process of erupting. The recall cephalogram and its tracing exhibit very minor changes in the dentition. The superimpositions confirm continued mandibular change, but this change has merely enhanced the harmony of the lower face. The pretreatment/posttreatment/recall smiling photographs confirm a very balanced face as well as a broad and esthetic smile. 8 9 Case #3 – Ryleigh Day Unlike the two patients whose records have been shown, facial photographs of this 11 year old female show facial imbalance. The mandible is retruded in relation to the maxilla. The casts exhibit an end to end Class II dental relationship, minor crowding, and a 3 mm curve of Spee. The panoramic radiograph illustrates a healthy dentition and the absence of, or poor development of, third molars. The cephalogram and its tracing confirm the retrusion of the mandible in relation to the maxilla with an ANB of 5°. The FMA is a normal 23°. Mandibular incisors are protruded at 99°. There is minor crowding and a need to upright mandibular incisors as well as to protract the mandibular molars. The craniofacial difficulty is only 19. Total difficulty is 53.5, due to the Class II dental relationship. 10 The maxillary first premolars and mandibular second premolars were extracted. Maxillary premolars were extracted because maxillary incisors needed to have proper third order inclination and intrusion as well as retraction because the mandibular incisors had to be uprighted. The pretreatment/posttreatment facial photographs exhibit a pleasing and more balanced face than the pretreatment face. The chin projection is much better at posttreatment. Pretreatment/posttreatment casts exhibit the interdigitated Class I occlusion with maintenance of arch form and arch width. The posttreatment panoramic radiograph reveals a healthy dentition and the developing third molars in the mandibular left and in the maxillary right and left quadrants. The third molars are not a factor. The pretreatment/posttreatment cephalograms confirm the fact that the maxillary incisors were retracted and their axial inclination was improved. Pretreatment/posttreatment tracings illustrate mandibular incisor uprighting from 99° to 89° while vertical control was maintained. The pretreatement/posttreatment superimpositions confirm vertical control, downward and forward mandibular change, and uprighting of mandibular incisors as well as intrusion and retraction of maxillary incisors. These carefully controlled movements without vertical expansion were important and essential for favorable mandibular change. Pretreatment/posttreatment smiling photographs confirm an improved smile arc and proper placement of the maxillary and mandibular anterior teeth in the face. 11 12 Though these three patients had different problems, their treatment plan of maxillary first premolar/mandibular second premolar extractions was appropriate. Each received benefit from his/her treatment. This extraction sequence is a very versatile treatment plan decision. Many types of malocclusions can be successfully treated with this extraction pattern. It is important to remember that it should probably not be considered when the vertical dimension of the patient is high and/ or if the patient has excessive mandibular crowding. This extraction pattern should be seriously considered, however, for patients who present with combinations of a significant Class II malocclusion, a deep curve of Spee, minor to moderate mandibular anterior crowding, and normal or below normal vertical dimension. 13 A New Twist on 3rd Order Bob Stoner Indianapolis, Indiana The purpose of this discussion is to elucidate some variables that affect 3rd order control. (Fig. 1) Fig. 1 Numerous “experts” have devised bracket systems that are based on “ideals” for the third order of each individual tooth. These bracket systems claim to require little third order adjustment in “most cases” and ideals for each bracket are based on the average 3rd order needed to achieve the ideal position. One can see from the chart of the seven bracket types sold by Ormco that there is great variability in the 3rd order for each tooth between bracket systems. 3rd Order Prescriptions in Ormco Catalog Rx Max 5 Max 4 Max 3 Max 2 Max 1 Mand Mand 2 Mand 3 Mand 4 Mand 5 I -7° -7° 0° 7° 14° -1° -1° -7° -11° -17° II 0° 0° 7° 14° 22° 0° 0° 7° 0° 0° III -7° -7° 3° 7° 14° -5° -5° -7° -11° -17° IV -8° -6° 3° 9° 15° -5° -5° -6° -7° -9° V -7° -7° 7° 10° 17° -6° -6° 7° -17° -17° VI -8° -6° 7° 14° 22° -10° -10° -6° -7° -17° VII -3° -2° 0° 9° 11° 3° 3° -2° -8° -8° VIII -11° -11° -7° 0° 7° -6° -6° -11° -17° -22° 11° 11° 14° 14° 15° 10° 10° 9° 17° 22° Range Fig. 2 In 1957 Stifter received a patent for the first preadjusted “straight-wire” appliance that was supposed to eliminate the need for wire bending. However, the specialty was focused on individual treatment at that time rather than on practice 14 management. Thus, the appliance was never accepted. Have these technological advancements in bracket manufacturing really improved the control of the edgewise appliance? Can we rely on “magic” appliances to replace the development of the skills required to manipulate the edgewise appliance in harmony with treatment? Or do we still need to develop the hand/eye coordination and finesse that has always been a requirement for quintessential orthodontic treatment. Fig. 5: Variation in the occluso/ incisal-gingival position of the bracket on the tooth Fig. 6: Variation in adhesive thickness Fig. 3 Evaluate the validity of standardization of 3rd order relative to: 1. Variability of a crown’s labial morphology for a given tooth type (Fig. 3 and 4) 2. Variability due to occluso/inciso-gingival position of the bracket (Fig. 5) 3. Inconsistent bracket adhesive thickness (Fig. 6) 4. Variability of the long-axis of the crown relative to the long axis of the tooth (Fig. 7) 5. Differences in the slot size to wire size (“wire / bracket slop”) (Fig. 8) Fig. 7: Variation in crown root anglulation Fig. 8: Deviation angle Fig. 4: Variation in labial morphology 15 Also, there are times during treatment when the 3rd order needs to be routinely changed in order to maintain or change the moment to force ratio. In the following example of uprighting the mandibular incisors, it is apparent that the 3rd order needs to be increased with successive adjustments to maintain the position of the incisor apex as the tooth is uprighted. (Fig. 9) Fig. 11: Long axis of tooth and crown Fig. 9: Uprighting lower incisors around the apex requires sequentially increasing anterior 3rd order in the closing arch In order to determine the degree of variability in the 3rd order requirement due to differences in the labial morphology of the crowns, differences in the crown to root angulation, and differences in the occluso/gingival bracket position, 25 extracted teeth of each tooth type were measured. Mandibular central and lateral incisors were grouped together as they were considered to be very similar. Also, 3rd molars were not measured. Each tooth was placed on an opaque overhead light projector and their shadows were magnified and projected onto paper. The outlines of each tooth were traced and were measured. A line was drawn relative to the long axis of the crown (LAC) and the long axis of the tooth (LAT). Perpendiculars were drawn from LAC to the labial surface of the crowns at the middle and at the incisal or occlusal third to represent two different bracket positions. From these two points, tangents were drawn and the angles were measured. (Fig. 10 and 11) ɑ1 is the angle formed by the tangent at the incisal 1/3 and the long axis of the tooth (LAT). ɑ2 is the angle formed by the tangent at the middle of the crown relative to the longaxis of the tooth. ɑ1 - ɑ2 = the difference in 3rd order inherent in the change in bracket position between the incisal 1/3 and the middle of the crown for an individual tooth. The results are shown below. (Fig. 12) Maxillary Central Incisor Maxillary Lateral Incisor Maxillary Canine Maxillary 1st premolar Maxillary 2nd premolar Maxillary 1st molar (mesio-buccal cusp) Maxillary 1st molar (disto-buccal cusp) Maxillary 2nd molar Mandibular incisor Mandibular canine Mandibular 1st premolar Mandibular 2nd premolar Mandibular 1st molar Mandibular 2nd molar Min 1° 3° 0° 0° 2° -13° Max 13° 13° 11° 14° 18° 17° Mean 6° 7° 6° 9° 8° 6° SD ±3° ±2° ±3° ±3° ±4° ±5° 0° 20° 9° ±5° -10° -4° 2° 2° 7° 2° 1° 20° 8° 11° 20° 21° 20° 23° 5° 3° 7° 9° 11° 10° 11° ±6° ±3° ±3° ±5° ±4° ±6° ±5° Fig. 12: Variability in 3rd order due to change in bracket position for each tooth type Fig. 10: Long axis of tooth and crown The range of 3rd order was quite severe for some of the teeth. And each tooth type has at least one out of the 25 samples that varied more than 10̊ (except the mandibular incisors) and some varied even more thant 20̊. 16 ɑ2 is the angle formed from the center of the crown to the longaxis of the tooth (LAT). The variability of ɑ2 between the 25 samples within each tooth type constitutes the difference in the degree of 3rd order required for each of the tooth types in order to maintain the long axis in the same direction. The variability is shown in figure 13 below. Maxillary Central Incisor Maxillary Lateral Incisor Maxillary Canine Maxillary 1st premolar Maxillary 2nd premolar Maxillary 1st molar (mesio-buccal cusp) 10° 15° 16° 22° 26° st Maxillary 1 molar (disto-buccal cusp) 24° nd Maxillary 2 molar 30° Mandibular incisor 12° Mandibular canine 16° Mandibular 1st premolar 25° 22° nd 34° st Mandibular 1 molar 30° Mandibular 2nd molar 21° Mandibular 2 premolar rd Fig. 13: Range of 3 order variation at the middle of the crown Even if one were to accurately position the bracket in the exact center of the crown of each tooth, the variation in 3rd order would vary between the 25 patients the amount shown in figure 14. One could expect that if these 25 patients were to walk into your office, you would need to vary the 3rd order by 16̊ for the maxillary canines and 34̊ for the mandibular 2nd premolars. Sometimes root position supersedes crown position when the root begins to approximate the cortical bone or an adjacent root. Therefore, variation in the crown to root angulation can be a factor in the 3rd order requirement for a tooth. The variability in the labiolingual direction of the crown to root can be inferred from the angle LAC to LAT. (Long-axis of the crown to the long-axis of the tooth). The variability within each given tooth type is shown in figure 14. It is also quite apparent that significant adjustment will need to be made to prevent root impingement in some cases. Maxillary Central Incisor Maxillary Lateral Incisor Maxillary Canine Maxillary 1st premolar Maxillary 2nd premolar Maxillary 1st molar Maxillary 2nd molar 8° 14° 8° 14° 12° 15° 19° Mandibular incisor Mandibular canine Mandibular 1st premolar Mandibular 2nd premolar Mandibular 1st molar Mandibular 2nd molar 14° 8° 14° 19° 14° 21° Fig. 14: Difference in long-axis of the tooth (LAT) to the long-axis of the crown (LAC) Summary and Conclusions: 1. The variability of the labial convexity of the crowns is statistically and clinically significant. This variability will necessitate significant adjustments to the appliance relative to any pre-adjusted 3rd order bracket or pre-set standard to achieve the desired 3rd order positioning. 2. The variability produced from differences in the bracket position is statistically and clinically significant. This variability will necessitate significant adjustments to the appliance relative to pre-adjusted 3rd order bracket or pre-set standard to achieve the desired 3rd order positioning. 3. The variability in the crown to root angulation is statistically and clinically significant. 4. Differences in the adhesive thickness, bracket “slop”, moment to force ratio changes and maintenance will all add to the necessity for significant adjustments to the appliance relative to pre-adjusted 3rd order bracket or standard bracket to achieve the desired 3rd order positioning. Therefore, this study shows that one cannot depend on the preadjusted bracket nor on a specific standard bracket to achieve ideal tooth positioning. WE MUST BEND THE WIRE! * Statistical tables and analyses were omitted but are available from Dr. Stoner 17 The Human Face…Our Past…Present…Future? Dennis Ward Avon Lake, Ohio The study of human evolution is the study of the human face, in particular, the mouth. Our first sensory organ was the mouth; then the teeth. The story of how our faces have evolved through millions of years of adaptation is essentially a story about the mouth. From early bags of cells that organized and combined to form a primitive hole to better assimilate food, to the complex skeleto-facial structure of modern Homo sapiens; our mouth has been foremost in determining the structure, esthetics and function of the human face. Survival of any species is dependent upon two basic functions: procreation and sustenance. Our faces and in particular, the anatomic position of our teeth, has been at the forefront of our evolutionary development. For millions of years of evolution and countless environmental adaptations, our early hominid ancestors were designed for survival and efficiency. As our brain capacity increased and our ability to reason and logically solve problems expanded, our faces continually receded below the cranial vault (Figure 1). Figure 1 Approximately 50,000 years ago Homo sapiens appeared. With a brain capacity of 1500cc, which nearly tripled the capacity of their early cousins, new abilities were in reach. Fire, tools and communication were all being employed to further expand the growing population (Figure 2). There are two prevailing theories on why our faces receded to present day dimensions. One is that as our size increased (the early hominids were 4 feet tall), our brain cavities also increased. This increase in size expanded our ability to think and develop more efficient ways to obtain and prepare food. The masticatory system became less dependent on mechanical efficiency, thus it moved under the face as the brain expanded. Figure 2 18 The second theory is much more interesting. Human beings are “hard wired” for symmetry. When given choices between beauty and ugliness, symmetry or asymmetry, we will always choose symmetry. Symmetry is biologically relevant to the survival of the species! The human face is the equivalent of the peacock’s tail. The more attractive a face, the more likely to mate. So the second theory of why the lower face receded beneath the upper face is it was more symmetric, thus a more attractive face. In 1946, Dr. Tweed published “The Frankfort-Mandibular Plane Angle in Orthodontic Diagnosis, Classification, Treatment Planning and Prognosis” in The American Journal of Orthodontics and Oral Surgery. In his review of the article Dr. Herb Margolis praised Dr. Tweed for recognizing that “uprighting incisors was in direct harmony with evolutionary trends in the development of man and tipping these teeth forward by the orthodontist is, in my opinion, ‘evolution in reverse’”. Figure 4 The following patient (Figures 3 to 12) is an example of expansion treatment, or as Margolis would say, “evolution in reverse”. Jody Turner is a 53 year old woman who had orthodontic treatment twice. The treatment plans involved a non premolar extraction protocol. The protrusion of her mandibular incisors was marked. Retreatment with a proper treatment plan gave her a balanced face. Figure 5 Figure 3 FMIA FMA IMPA SNA SNB ANB AO/BO 44 20 116 82 77 5 6.6mm OP Z UL TC PFH AFH MI 0 65 6.3mm 16mm 52.1 71.7 0.73 Figure 6 19 Total Space Analysis T/A disc. 0 Headfilm 19.2 Total 19.2 Mid: T/A disc. 0 COS 2.1 Total 2.1 Ant: Occ. Disharmony Post: Total: 0 2.8 18.5 Pretreatment Figure 7 FMIA FMA IMPA SNA SNB ANB AO/BO OP Z UL TC PFH AFH MI 44 20 116 82 77 5 6.6 0 65 6.3 16 52.1 71.7 0.73 Posttreatment 71 18 91 82 79 3 2.5 -1 84 9.7 13.9 54.3 69.4 0.78 Figure 11 Figure 8 Figure 12 Figure 9 The philosophy of “expand the dental arch at all costs” is not new. It is in direct contrast to symmetry and balance. How it ends is up to us. This trend can only be fought with proper diagnosis. It is the significant contribution we can make to our specialty. Figure 10 20 Why the Single Bracket? Elie Amm Jbeil (Byblos), Lebanon There are many types of brackets available. This fact makes the choice of brackets difficult for the experienced clinician and even more difficult for the newly graduated orthodontist. Are there advantages with the single bracket that the twin bracket does not have? Current orthodontic practice trends are highly influenced by the marketing skills of supply companies and the folks who lecture for them. Most of the time, commercial interests go in a divergent direction than scientific values. Nonevidenced based data can mislead the clinician into a poor treatment plan that results in poor treatment for the patient. Good treatment (Figures 1, 2 and 3) requires a proper treatment plan and force system. A newly graduated orthodontist is considered an easy target for the “gurus” of the market. I did an in-depth study to find the system that would keep me independent and true to scientific principles. Everybody wants a system that is simple, affordable, good for all circumstances, and efficient. Orthodontists are always obliged to individualize the 1st, 2nd, and 3rd order bends for each patient during a particular phase of treatment. To face the huge variety of brackets available in the market and the company’s ads can cause a lot of confusion. I went “back to basics” and chose the standard edgewise single bracket! Call this technique Tweed + 5 Minutes – an illusion to the five minutes that is spent to bend a wire. In fact, these five minutes are very useful and could be considered a marketing tool. During this 5 minutes, patients can brush their teeth without wasting time, and/or the doctor can socialize with the patient and/or the patients’ family. The single bracket allows the orthodontist to have one bracket for all the teeth. The only difference between premolar and anterior brackets is the pad design that fits the labial surface. There is one bracket for maxillary and mandibular incisors, and one for maxillary and mandibular cuspids and bicuspids. When only one bracket is used for all the teeth, the true variable is the archwire. Figure 1 Figure 2 21 Figure 3 Is this bracket system efficient? Interbracket width answers this question. Interbracket width depends on the size of the teeth and the size of the bracket; it is obvious that to increase the interbracket width one has to decrease the size of the bracket. With sequential bonding (Figure 4) it is very important to increase the interbracket width as much as possible in order to decrease the “stiffness” of the system. Stiffness is inversely proportional to the interbracket width. Creekmore stated that: “Surprisingly, light forces depend more on interbracket width than archwire size.” With the single bracket one has: 1) patient comfort 2) exactness of posterior loops and hooks 3) a decrease in the number of round archwires required 4) an increase in the first rectangular archwire’s dimensions 5) a decrease in the total number of archwires 6) early leveling 7) early torque control 8) arch form control and 9) a decrease in the treatment time. (Figures 6 and 7) The twin bracket proponents consider rotational control easier because only one wing of the bracket is tied to the archwire and the rotation is corrected quickly. This fact is true but there are sometimes problems. For example, during the correction of a severe rotation, the clinician is obliged to bond the wider twin bracket off the center of the tooth and rebond it in the right position after partial rotation correction. This problem is less likely with the single bracket because it is narrower and the chance to bond it in the right position at the outset is better (Figure 8). With a single bracket the clinician can use some rotational auxiliaries like a Steiner wedge. An easy and simple way to correct the rotations is to use a power chain! Another “marketing” tool the single bracket presents is that it is considered by many patients to be the most esthetic metal bracket (Figure 9). There is no study to prove this idea, but our practice has patients who seek this kind of bracket. It is our “trademark” in our small town in Lebanon. Figure 5 Figure 6 Figure 7 Figure 8 Try staying single (with brackets)! You will like it. Consider Tweed + 5 minutes (Figure 10). Figure 9 Figure 4 Figure 10 22 Class III Correction and Surgical Orthontics: the Good, the Bad, and the Ugly Mike Behnan Clinton Township, Michigan Introduction Tweed-Merrifield orthodontists have placed great emphasis on the facial profile. When a patient is best treated in conjunction with orthognathic surgery, our oral-maxillofacial surgeon colleagues have largely determined the surgical procedure. By doing so they greatly influence the final result. Occasionally, our treatment objectives are out of sync with those sought by the surgeon, particularly with Class III malocclusions. There seems to be a trend to prefer Le Fort I maxillary advancements over mandibular setbacks – even for patients with mandibular prognathism. Concern over airway space is often cited as the rationale for avoiding mandibular setbacks. While the airway certainly has its place in the diagnostic process, advocating maxillary advancements only could compromise esthetics when a mandibular setback is warranted. This paper seeks to demonstrate the importance of the diagnostic process and its impact on the treatment result. The patient records presented show some good, some bad, and some ugly esthetic finishes. Case #1: The Good Our first patient represents what we will classify as a “good” result. The Class III female patient presented with an obvious mandibular prognathism along with dental compensations for the skeletal discrepancy (Figure 1). The task at hand was to remove dental compensations in preparation for a mandibular setback surgery. Thus, a Class II extraction pattern of maxillary first premolars and mandibular second premolars was selected. Post-surgical treatment records demonstrate a pleasing facial profile and an excellent orthodontic result (Figure 2). 23 Figure 1: Pretreatment records for case #1. A, extraoral photos. B, intraoral photos. C, panorex. D, lateral cephalogram. Figure 2: Post-treatment records for case #1. A, extraoral photos. B, intraoral photo. Case #2: The Bad Our second patient falls into what can be called a “bad” result. This adult male presented with a severe Class III malocclusion (Figure 3). The surgical cephalometric analysis often used by Bilodeau1 features the measurements of Tweed2, McNamara3, Delaire4, and Legan5. The pretreatment SNB of 90º and Delaire’s FM point-clivusmenton angle of 104º (ideally between 85º and 90º) indicate mandibular prognathism. Additionally, McNamara’s nasion Frankfort perpendicular to Point A indicates that the maxilla’s anteroposterior position is ideal. Despite our diagnosis of mandibular prognathism, the maxillofacial surgeon insisted on a Le Fort I maxillary advancement. This significant repositioning of a single jaw corrected the Class III malocclusion, but resulted in what many would deem an unsatisfactory facial result (Figure 4). The mother of the patient was particularly dissatisfied with the result. Figure 4: Posttreatment records for case #2. A, extraoral photos. B, intraoral photos. Figure 3: Pretreatment records for case #2. A, extraoral photos. B, intraoral photos. C, panorex. D, lateral cephalogram. 24 Case #3: The Ugly Our final case report falls under the category of “ugly” in the opinion of the author. This adult male presented with a severe Class III malocclusion (Figure 5). The significant anteroposterior dental discrepancy suggested orthodontic treatment be done in conjunction with orthognathic surgery. Despite the dental discrepancy, the facial profile seems rather pleasant for an adult male. The cephalometric analysis points to both moderate maxillary prognathism and severe mandibular prognathism. While the author anticipated a mandibular setback surgery only, the maxillofacial surgeon insisted on some degree of maxillary advancement. This decision raised concern, especially since the patient already had some degree of maxillary prognathism. In any event, the surgery proceeded, and a post-surgical lateral cephalogram indicates that an unplanned advancement genioplasty was performed as well. It is possible that the genioplasty was included to offset the controversial maxillary advancement. Either way, the post-surgical extraoral photos (Figures 6 and 7) demonstrate an unpleasant facial profile. In comparison to the initial profile, the posttreatment profile seems unbalanced, aged, and less masculine. Despite an otherwise excellent orthodontic result, the ill-advised surgical treatment may have spoiled the treatment. Figure 5: Pretreatment records for case #3. A, extraoral photos. B, intraoral photos. C, panorex. D, lateral cephalogram. 25 Figure 6: Posttreatment records for case #3. A, extraoral photos. B, intraoral photos. Figure 7: Cephalometric analysis for Case #3. Conclusions A complex treatment plan that requires orthognathic surgery demands a careful diagnosis and treatment plan. Attempting to treat otherwise or to simply “straighten the teeth” before surgery may produce “bad” or “ugly” results. Perhaps the time has come for the orthodontist to get more directly involved with the surgical treatment planning before our patients walk into the operating room. References 1. Bilodeau JE. Correction of a severe Class III malocclusion that required orthognathic surgery: a case report. Semin Orthod 1996;2(4):279-88. 2. Tweed CH. A philosophy of orthodontic treatment. Am J Orthod Oral Surg 1945;31:74-103. 3. McNamara JA. A method of cephalometric evaluation. Am J Orthod. 1984;86:449-469. 4. Delaire J, Schendel SA, Tulasne JF. An architectural and structural craniofacial analysis: A new lateral cephalometric analysis. J Oral Surg 1981;52:226-238. 5. Legan HL, Burstone CJ. Soft tissue cephalometric analysis for orthognathic surgery. J Oral Surg 1980;38:744751. 26 Cephalometrics Revised Hiroshi Maruo Claudio Vinícius Sabatoski Orlando Tanaka Armando Yukio Saga Ivan Toshio Maruo Introduction As technological advances become more available to our specialty, the professional needs to use his/her good sense and judgment. Are we ready to leave cephalometrics and cephalometric analyses behind for CBCT or MRI imaging?1 Kragskov et al.2 stated that conventional cephalometry is an inexpensive and well-established method for evaluating patients with dentofacial deformities, and that there is no evidence that CB CT is more reliable. The benefit of 3D CT cephalometrics could be for severe asymmetric craniofacial syndromic patients. But we must ask if the specialty has learned everything about two-dimensional imaging. For example, discussion about the use of either Nasion or Occlusal Plane as landmarks is well-know but still controversial.3 Although cephalometrics has been extensively studied, little attention has been paid to how an inexperienced orthodontist can integrate apparent cephalometric discrepancies with clinical findings in order to reach a proper treatment plan for the patient. Methods Since the first cephalometric analysis4, all cephalometric analyses – including 3D cephalometric analyses5 – follow the same step: the patient’s values are compared with average standard values which were obtained from attractive faces of people with normal occlusions. However, orthodontic patients have a malocclusion and usually show a lack of facial balance and harmony6. So, more than to standardize, the goal of every orthodontist should be to individualize the cephalometric analysis to the patient. The Tweed-Merrifield cephalometric analysis was chosen for this study because it, like other analyses, uses measurements that indicate the skeletal, dental and esthetic patterns of patients. The standard values for the Tweed Merrifield analysis are shown in Fig. 1. Before orthodontists totally embrace 3D imaging, it would be wise to look back to what we know and what we do not know about cephalometrics. The purpose of this article is to discuss tracing or measurement errors, to show the more frequent disparities and incongruencies in a cephalometric analysis and to assess and explain them with individual case reports. By becoming familiar with all these issues, cephalometrics can be more fully understood and the specialty will be able to apply the same reasoning to interpretation of 3D imaging in a way that will provide quality service to our patients. Fig. 1: Tweed-Merrifield Cephalometric Analysis 27 Case #1 A male, 15 years-old, with a dolichofacial, convex profile and lack of lip seal had a Class II division 1 malocclusion with an overjet of 9.0 mm (Figs. 2, 3). How can this Class II division 1, patient have an ANB of 1.0º, and AO-BO of –9.0 mm? If the SNA and SNB angles show, respectively, the anterior or posterior position of the maxilla and the mandible, aren’t the decreased measurements of this patient an indication that they are retracted? How can a convex profile and a Z angle of 65.0º be explained if the SNA measures 72.0º and SNB measures 71.0º? If the cephalogram is studied, the reasons are not so very difficult to explain. ANB is 1.0º because the patient’s face is “vertical” and his anterior cranial base is inclined downward — S point is lower than point N. The anterior cranial base is longer as a result of Nasion being more forward. The more forward point N, the more ANB decreases. So, the more forward point N is located and the more inferior S is located to cause of a more inclined anterior cranial base, the more the SNA, SNB and ANB angles decrease. Fig. 2: Case #1 Pretreatment Photographs AO-BO is -9.0 mm because of the vertical facial type and because of the inclined occlusal plane. As the occlusal plane incline increases, the projection of A and B points tends to decrease progressively. If the anterior cranial base and occlusal plane are excessively inclined, the SNA, SNB and ANB are decreased. This boy’s face should be much more vertical than the FMA indicates. If the AO-BO of -9.0 mm is due to the occlusal plane’s accentuated inclination, which is compatible with extremely vertical faces, it is confirmed by the following values: PFH of 42.0 mm, AFH of 78.0 mm and FHI of 0.53. Although FMA is 34°, it does correspond to these other measurements, which leads to the possibility of a Frankfort plane tracing error. And assuming that this interpretation is true7,8, it is possible to understand why occlusal plane and Z angle are not as inclined as they would be expected to be with AO-BO of -9.0 mm and FHI of 0.53. These discrepancies could somewhat compromise the cephalometric discrepancy calculation, which in this case would be even greater if SNA, SNB and ANB were more reflective of the skeletal problem. Several studies7-10 confirm this possibility for this patient. Fig. 3: Case #1 Cephalometric Tracing and Analysis Case # 2 This male patient, treated fifteen years ago, was 18 yearsold, brachifacial and had a straight and harmonious profile with good lip seal. The Class II division 2 malocclusion has normal overjet and overbite and coincident midlines (Figs. 4 and 5). His frontal and profile photographs (Fig. 4) show a well balanced and harmonious face which does not reflect the malocclusion that is exhibited by the casts. Cephalometrically (Fig. 5), an ANB of 5.0º indicates a skeletal Class II while an FMIA of 53.0º and an IMPA of 105.0º confirm protruded mandibular incisors. The Z angle of 80.0º reflects a straight and balanced profile. If one uses 28 it must be understood that the low mandibular plane angle dictates the mandibular incisors’ labial inclination. This is nature’s compensation to disguise the Class II so that the profile is balanced. If a cephalometric correction had been done and the mandibular incisors uprighted, the maxillary incisors, which are normal, would have an unesthetic lingual inclination. The patient was treated without extractions. The results are shown in Figs. 6 and 7. The frontal and profile photographs (Fig. 6) show good lip seal, proportional and symmetrical facial thirds and a straight and balanced profile. Maintenance of the balanced and harmonious face was a pretreatment goal. Fig. 4: Case #2 Pretreatment Photographs Fig. 6: Case #2 Posttreatment Photographs Fig. 5: Case #2 Cephalometric Tracing and Analysis a cephalometric discrepancy calculation, IMPA should be 68.0º. To reach this value would require mandibular extraction to upright the mandibular incisors. Is it possible to upright the mandibular incisors this much? What about maxillary incisor position? Why are the mandibular incisors so buccally inclined and the maxillary incisors so well positioned? Ordinarily, aren’t the incisors balanced by lips and by tongue? For this patient we cannot think in the manner just described. The Z angle is 80.0º and the profile is straight. The IMPA is 105° to compensate the Class II skeletal pattern, as the ANB and AO-BO show. And ANB and AO-BO are not significantly large because the gonial angle is closed. The FMA is low. So, 29 Fig. 7: Case #2 Cephalometric Tracing and Analysis The frontal and lateral views of the casts (Fig. 6) show the corrected dentition with good interdigitation of the teeth. Thus, it was possible to treat the patient and respect nature’s compensation while correcting the Class II dental problem. There is no doubt about the fact that it was “hard” treatment. The patient’s five year recall photographs (Fig. 8) show that the profile became more “flat”. Imagine what would have happened to the profile with extraction treatment. It is important to understand that the issue here is not to repudiate or to discredited an analysis, but to interpret it correctly. Case # 3 The patient is 15 years, 6 months old with a Class III dentition. He has a balanced and harmonious face with good proportions that does not reflect a malocclusion (Fig. 10). This worsening of the patient’s profile with age cannot be attributed to the orthodontic treatment. As the cephalometric analysis shows (Fig. 9), the profile change was due to total chin growth from the beginning to the end of the period studied. However, if this patient had been treated with extractions to upright mandibular incisors, the facial result would have been disastrous and a reason for a lot of criticism of the treatment. The frontal view of the casts (Fig. 10) shows edge-to-edge incisors, maxillary spacing and 7mm of mandibular anterior crowding. The lateral views (Fig. 10) show teeth in a Class III relationship and molars and premolars with sharp vestibular inclinations. This occlusion was probably due to previous orthodontic treatment which attempted to excessively expand the dental arches. The cephalometric analysis (Fig. 11) shows increased SNA and SNB values in relation to the average standard values. FMA is 23.0º; FMIA should be of 68.0º. The patient’s FMIA is 71.5º. These numbers indicate mandibular incisor uprighting is not necessary. But the discrepancy is based on people with normal occlusion with ANBs close to 2.0º. Whereas, in this patient the malocclusion is Class III with ANB of -2.0º and the AO-BO is -7.5 mm. Fig. 8: Case #2 Recall Treatment Photographs Fig. 10: Case #3 Pretreatment Photographs Fig. 9: Case #2 Cephalometric Tracing and Analysis Fig. 11: Case #3 Cephalometric Tracing and Analysis 30 There is no doubt that there must be some sort of dental compensation. So, for this patient, what would be the compensation or cephalometric discrepancy? One of the most important aspects is the patient’s profile which, despite a Z angle of 85.5º, is very well balanced and harmonious — not concave. This is due to head anatomy with the increased PFH and, consequently, with an increased FHI as well. Maxillary incisor position must be considered and left as it is pretreatment. So, it should be reasoned that the mandibular incisor position must compensate for the negative ANB with a much more lingual inclination than it would be with an ANB of 2.0º. Because the maxillary incisor is not only well positioned but is stable, and the lower facial profile is both harmonious and balanced, the mandibular incisor must be changed as much as is necessary in order to establish normal overjet and overbite as well as to maintain the balanced and harmonious profile. So going counter to the traditional cephalometric discrepancy calculation rule, the mandibular incisor must be inclined 3.5 mm lingual – which is equivalent to 7.0 mm of cephalometric discrepancy. Considering this discrepancy, the malocclusion type and the maxillary third molar agenesis, treatment was planned with mandibular first molar extractions. In order to evaluate this type of reasoning, there is nothing better than this patient’s treatment result (Figs. 12 and 13). Fig. 13: Case #3 Cephalometric Tracing and Analysis lingual, the same profile was maintained, that is, the Z angle remained exactly the same. Conclusions With critical evaluation and rational interpretation of these patients’ cephalometric analyses, there is no motive for the statement that one analysis dictates extraction of more or less teeth than another. It becomes clear that differences between cephalometric analysis methods, the extraction or lack of extraction of teeth and facial profile management depend In the frontal and profile photographs (Fig. 12) there is good exclusively on the professional’s interpretation. lip seal with a straight profile. Facial balance and harmony were maintained. The frontal and lateral views of the The following conclusions can be reached: casts (Fig. 12) show good interdigitation of the teeth, with mandibular second and third molars occupying, respectively, 1. In the utilization of the Tweed-Merrifield cephalometric analysis it is possible to detect tracing errors through the first and second molar positions (Fig. 13). There was measurement interpretation as a whole. maintenance of ANB and improvement in AO-BO to 1.5 2. ANB and AO-BO do not always reflect a skeletal anteriormm. Although the mandibular incisors were inclined to the posterior discrepancy. 3. SNA and SNB do not always accurately confirm the anterior or posterior position of the jaws. Their increase or decrease in relation to the average standard value could be caused by a shorter or longer cranial base as well as its inclination. 4. The cephalometric discrepancy is misinterpreted some times and should not be a definitive application of a simple mathematical rule. 5. The position of the maxillary incisor as well as ANB, AO-BO, FHI and Z angle helps to interpret and clarify a cephalometric discrepancy. Fig. 12: Case #3 Posttreatment Photographs 31 References 1. Halazonetis DJ. From 2-dimensional cephalograms to 3-dimensional computed tomography scans. Am J Orthod Dentofacial Orthop 2005;127:627-637. 2. Kragskov J, Bosh C, Gyldensted C, Sindet-Pedersen S. Comparison of the reliability of craniofacial anatomic landmarks based on cephalometric radiographs and three-dimensional CT Scans. Cleft Palate-Craniofacial J 1997;34(2):111116,. 3. Jacobson A. The “Wits” appraisal of jaw disharmony. Am J Orthod Dentofacial Orthop 2003;124(5):470-479. 4. Downs WB. Variations in facial relationships: their significance in treatment and prognosis. Am J Orthod 1948;34:812– 840. 5. Park SH, Yu HS, Kim KD, Lee KJ, Baike HS. A proposal for a new analysis of craniofacial morphology by 3-dimensional computed tomography. Am J Orthod Dentofacial Orthop 2006;129(5):600.e23-600.e34. 6. Tweed CH. Clinical Orthodontics: volume one. St. Louis (MO): Mosby Company; 1966. 7. Sandler P. Reproducibility of Cephalometric Measurements. Br J Orthod 1988;15:105-10. 8. Cooke M, Wei S. Cephalometric errors: a comparison between repeat measurements and retaken radiographs. Aust Dent J 1991;36:38-43. 9. Gravely J, Benzies P. The clinical significance of tracing error in cephalometry. Br J Orthod 1974;1:95-101. 10. Staburn A, Danielson K. Precision in cephalometric landmark identification. Eur J Orthod 1982;4:185-96. 32 Case Reports A Case Report: A Full Step Class II Patient Revisisted 27 Years Posttreatment Vance Dykhouse Blue Springs, Missouri Tammy Sage had comprehensive orthodontic treatment in the mid 1970’s. She returned to our office to have her son treated in 2005. We made a set of records in 2005, almost twenty-eight years after her treatment was finished in 1977. Tammy’s case was originally presented with three sets of records at a Central Section Tweed meeting in 1979. A two-year post-treatment set of records was almost a necessity for case presentations at that time. Tammy presented a bilateral full step Class II, Division I malocclusion without crowding. Her overbite was extremely deep. She was a non-grower, 14 years, 2 months in age at the beginning of orthodontic treatment. The decision was made to treat Tammy non-extraction despite a higher than desired IMPA. Good headgear wear and anchorage preparation would be a necessity for successful treatment. (Please pardon the glasses in the extra oral photographs.) 36 Tammy’s treatment began in 1975. She had a high mandibular frenum and a Stillman’s cleft on tooth #25 that is not visible on the beginning intraoral photographs. She had a graft in late 1975 that was successful. Tammy was an excellent patient. After initial leveling, she wore a straight pull J-hook headgear and Class III elastics to set mandibular anchorage. Mechanics were then reversed to a high pull J-hook and vertical elastics during sleeping hours with full-time Class II elastics. The bite was opened and a solid Class I occlusion was attained. Maxillary second molars were tipped out of occlusion, a la Tweed mechanics in use at that time. Active treatment time was 26 months. Tammy was 16 years, 5 months in age when appliances were removed and retention began. A third set of records was taken twenty-six months after appliance removal. Tammy was 18 years, 7 months of age. The Class I buccal occlusion had been maintained and the overbite had not returned. The maxillary molars settled into excellent occlusion. Third molars were gone. Spaces remained closed. A maxillary Hawley retainer and a lower fixed retainer were worn until this time. In 2005, Tammy returned to our office with her son who had a similar malocclusion, and was ready for 37 orthodontic treatment. A fourth set of records was made. Tammy was 44 years, 4 months of age. The records were taken 1 month shy of twenty-eight years post appliance removal. Tammy’s Class II correction has held well. Her overbite correction has also remained stable. The thirty year old gingival cleft has remained non pathological. She has had to have quite a bit of dental work over the past twenty five years. 38 Cephalometric measurements from the four sets of record are presented in summary form. Cephalometric Summary FMA IMPA FMIA SnGoGn SNA SNB ANB T to NB Pog to NB Int-Inc angle Occ-PL Ao-Bo Z angle 39 12/74 22 99 59 27 84.5 78 6.5 5 4 117 17 7 74 4/77 22 98 60 27 82 78.5 3.5 6 4 133 14 2.5 76 6/79 20 101 59 26 83 80 3 6 4 130 12 4 83 3/05 18 101 62 30 82.5 80.5 2 5 3 132 18 4 88 Case Report: Vertical Control in a High Angle Patient Who Needed R apid Maxillary Expansion (RME) Mauricio Escanola Tepic, Nayarit / Mexico In our professional life we are faced with patients whose malocclusions challenge us as orthodontists to test the concepts we have learned and to use our clinical judgment to apply the biomechanical resources that allow us to offer the patient facial esthetics, occlusal harmony and stability. Patients who combine a vertical hyperdivergent skeletal pattern with maxillary collapse are difficult to treat because the treatment of a patient with maxillary collapse requires maxillary expansion. The literature clearly demostrates that, immediately after expansion, there is downward maxillary displacement and extrusion of the supporting teeth which leads to downward and backward mandibular rotation2,4-6,8–10,14-17. The opening rotation of the mandible induces cephalometric changes such as increases in inclination of the mandibular plane, increases in lower anterior facial height and facial convexity bite opening in the anterior region. clinically related to insufficient width of the palatal vault, a deep palate and outward inclined dentoalveolar processes. All these factors indicate a skeletal maxillary constriction. Dentally, the patient has an edge to edge bite and severe crowding with ectopic maxillary canines (Fig. 1, 2). Cephalometric values show an FMA of 30°, an occlusal plane of 13°, a facial index of 61%, an IMPA of 87° and a Z angle of 76° (Fig. 3). Figure 1. Pretreatment photographs. In this context, some orthodontists have advised against performing RME in patients who have predominantly vertical growth patterns and convex facial profiles1,3 in order to prevent worsening of the malocclusion. However, a proper diagnosis, understanding of the functional forces and implementation of an appropriate force system that favors vertical and horizontal control during treatment are able to minimize the undesirable anteroposterior and vertical effects of RME7, 11-13, 20-23. Case Report Karen C., is a 16 year old young lady who presents a straight profile and a Class I malocclusion with a hyperdivergent skeletal pattern that is complicated by maxillary constriction and posterior crossbite due to the mouth breathing habit. According to Staley´s intermolar analysis24 the deficit of 8mm in the maxillary arch is Figure 2. Pretreatment dental casts. 40 Figure 3. Pretreatment cephalogram, cephalometric values and tracing. Figure 6. Posttreatment dental casts. The main factors associated with the treatment of this patient are: 1. High mandibular plane angle (hyperdivergent skeletal pattern) 2. Maxillary constriction 3. Dental crowding 4. Good facial profile Merrifield’s guidelines suggested that four first premolars should be extracted in order to solve the space problem . This patient was treated with rapid maxillary expansion (REM) before extractions and fixed appliances (Fig. 4) so that anchorage loss during the closure of the spaces would not affect facial balance. Posttreatment cephalometric values (Fig. 7) show that there was good vertical control since the FMA, the occlusal plane and facial index were not altered despite maxillary expansion. Z angle was increased to 79°. The superimpositions (Fig. 8) show that space closure was achieved with mesial movement of the molars and minimal anterior retraction so that facial balance would not be harmed. There was no posterior extrusion and therefore no clockwise mandibular rotation due to lack of vertical control. For a patient with a normal vertical dimension, and even more for a patient with a hyperdivergent skeletal pattern, to not have control of the vertical dimension predisposes to failure. On the other hand, good control of vertical dimension during treatment allows a predictable outcome. Figure 4. a) Post maxillary expansion; b) After 6 months of contention. The posttreatment records (Fig. 5, 6) illustrate that facial harmony was maintained. There was an improvement in the esthetics of the smile. Posttreatment casts confirm the improvement of the transverse dimension and shape of the maxillary arch as well as good arch coordination and occlusal interdigitation. Figure 5. Posttreatment photographs. 41 Figure 7. Posttreatment cephalogram, cephalometric values and tracing. Figure 8. Superimpositions. References 1. Alpern MC, Yurosko JJ. Rapid palatal expansion in adults with and without surgery. Angle Orthod. 1987;57(3):245–263. 2. Asanza S, Cisneros GJ, Nieberg LG. Comparison of Hyrax and bonded expansion appliances. Angle Orthod. 1997; 67(1):15–22. 3. Bishara SE, Staley RN. Maxillary expansion: clinical implications. Am J Orthod Dentofacial Orthop. 1987;91(1):3–14. 4. Byrum AG Jr. Evaluation of anterior-posterior and vertical skeletal change vs. dental change in rapid palatal expansion cases as studied by lateral cephalograms. Am J Orthod. 1971;60(4):419. 5. Chung CH, Font B. Skeletal and dental changes in the sagittal, vertical, and transverse dimensions after rapid palatal expansion. Am J Orthod Dentofacial Orthop. 2004;126(5): 569–575. 6. Davis WM, Kronman JH. Anatomical changes induced by splitting of the midpalatal suture. Angle Orthod. 1969;39(2): 126–132. 7. Garib DG, Henriques JF, Janson G, Freitas MR, Coelho RA. Rapid maxillary expansion--tooth tissue-borne versus tooth-borne expanders: a computed tomography evaluation of dentoskeletal effects. Angle Orthod. 2005;75(4):548-57. 8. Haas AJ. The treatment of maxillary deficiency by opening the midpalatal suture. Angle Orthod. 1965;35:200– 217. 9. Haas AJ. Rapid expansion of the maxillary dental arch and nasal cavity by opening the midpalatal suture. Angle Orthod. 1961;31(2):73–90. 10. Heflin BM. A three-dimensional cephalometric study of the influence of expansion of the midpalatal suture on the bones of the face. Am J Orthod. 1970;57(2):194–195. 11. Merrifield, L.L.: The profile line as an aid to critical evaluation of facial esthetics. Am J Orthod: 804-822, 1966. 12. Merrifield, L.L., Cross, J.; A study on directional forces. Am J Orthod., 1970. 13. Merrifield L.L.: Differential diagnosis with total space analysis. J Tweed 6: 10-15, 1978. 14. Sandikcioglu M, Hazar S. Skeletal and dental changes after maxillary expansion in the mixed dentition. Am J Orthod Dentofacial Orthop. 1997;111(3):321–327. 15. Silva Filho OG, Boas MC, Capelozza Filho L. Rapid maxillary expansion in the primary and mixed dentitions: a cephalometric evaluation. Am J Orthod Dentofacial Orthop 1991; 100(2):171–179. 16. Wertz R, Dreskin M. Midpalatal suture opening: a normative study. Am J Orthod. 1977;71(4):367–381. 17. Wertz RA. Skeletal and dental changes accompanying rapid midpalatal suture opening. Am J Orthod. 1970;58(1):41–66. 18. Reed N, Ghosh J, Nanda RS. Comparison of treatment outcomes with banded and bonded RPE appliances. Am J Orthod Dentofacial Orthop. 1999;116(1):31–40. 19. Sarver DM, Johnston MW. Skeletal changes in vertical and anterior displacement of the maxilla with bonded rapid palatal expansion appliances. Am J Orthod Dentofacial Orthop. 1989;95(6):462–466. 20. Wendling LK, McNamara JA Jr, Franchi L, Baccetti T. A prospective study of the short-term treatment effects of the acrylic-splint rapid maxillary expander combined with the lower Schwarz appliance. Angle Orthod. 2005;75(1):7–14. 21. Schulz SO, McNamara JA Jr, Baccetti T, Franchi L. Treatment effects of bonded RME and vertical-pull chin cup followed by fixed appliance in patients with increased vertical dimension. Am J Orthod Dentofacial Orthop. 2005;128(3): 326–336. 22. Chang JY, McNamara JA Jr, Herberger TA. A longitudinal study of skeletal side effects induced by rapid maxillary expansion. Am J Orthod Dentofacial Orthop. 1997;112(3): 330–337. 23. Velazquez P, Benito E, Bravo LA. Rapid maxillary expansion. A study of the long-term effects. Am J Orthod Dentofacial Orthop. 1996;109(4):361–367. 24. Robert N. Staley, Wendell R. Stuntz, Lawrence C. Peterson. A comparison of arch widths in adults with normal occlusion and adults with Class II, Division 1 malocclusion. American Journal of Orthodontics. August 1985 (Vol. 88, Issue 2, Pages 163-169) 42 Case Report: Treatment of a High Angle Adolescent Patient Kortne Frederick hou Tukwila, Washington This is the case report of an Angle’s Class I crowded, high mandibular plane angle malocclusion. The patient’s medical history was negative. Etiology of the malocclusion was heredity. Pretreatment Records The facial photographs (Fig. 1) exhibit a convex facial profile, lower lip eversion, and a retrognathic appearance of the mandible. The casts (Fig. 2) exhibit a deep overbite, an Angle’s Class I occlusion, a deep curve of Spee, and mandibular anterior crowding. The panoramic radiograph (Fig. 3) confirms that all teeth are present, the periodontium is healthy, and there is no pathology. The cephalogram and its tracing (Fig. 4a, b) confirm a high mandibular plane angle of 36°. Mandibular retrognathia is confirmed by the SNB of 74°. The Z angle is a poor 58° and both maxillary and mandibular lips are in front of the E plane. The craniofacial analysis difficulty value for this patient Fig. 1. Pretreatment photographs. 43 Fig. 2. Pretreatment dental casts. Fig. 3. Pretreatment panoramic radiograph. Fig. 4a. Pretreatment cephalogram and 4b) tracing. is 98. The total space analysis difficulty is 22.9. The patient’s total dentition difficulty was 120.9. Treatment Plan Due to the bialveolar protrusion and the 7 mm of mandibular anterior crowding, maxillary and mandibular first premolars were removed. The removal of these teeth was done in order to facilitate elimination of the crowding and reduction of the bialveolar protrusion. Posttreatment Records The pretreatment / posttreatment facial photographs (Fig. 5) confirm a more pleasing face with less protrusion of the lips. The smile line is vastly improved. The posttreatment casts (Fig. 6) exhibit correction of the crowding, a reduction in the overbite, and an excellent Class I interdigitation of the teeth. Arch width and arch form were preserved during the course of treatment. The the mandible due to vertical control during treatment and a nice downward and forward chin projection. The pretreatment/posttreatment smiles (Fig. 10) confirm the intrusion and retraction of the maxillary anterior teeth which resulted in much less gingival display upon smiling. Fig. 7. Posttreatment panoramic radiograph. Fig. 8a. Posttreatment cephalogram 8b.tracing. Fig. 5. Posttreatment photographs. Fig. 9. Superimpositions. Fig. 6. Posttreatment dental casts. posttreatment panoramic radiograph (Fig. 7) reveals that the teeth remain healthy and that all extraction spaces have been closed by adequate uprighting of teeth into the extraction spaces. The posttreatment cephalogram and its tracing (Fig. 8a, b) confirms retraction of teeth, control of the vertical dimension, and a marked reduction in the dental protrusion. The superimpositions (Fig. 9) illustrate an autorotation of Fig. 10. Pretreatment and Posttreatment smiles. 44 Case Report: Correction of a Severe Class II Division I Malocclusion in an Adolescent Patient Jack Hou Tukwila, Washington This is a case report of a young female who has an extreme protrusion of the teeth which causes a significant facial imbalance. The etiology of the malocclusion was heredity. There were no medical complications. Pretreatment Records The facial photographs (Fig. 1) exhibit a very convex face with quite a bit of mandibular lip eversion. The nasolabial angle is acute. The pretreatment casts (Fig. 2) exhibit a deep curve of Spee, an Angle’s Class II dental relationship, and flared maxillary and mandibular incisors. The pretreatment panoramic radiograph (Fig. 3) confirms that all teeth are present and the periodontium is healthy. The pretreatment cephalogram and its tracing (Fig. 4a, b) confirm very protruded maxillary and mandibular incisors, a Class II skeletal relationship, and a very low Z angle. The craniofacial difficulty for the patient was only 34 because the skeletal pattern was reasonable. The tooth arch discrepancy for this patient was 22 mm because of the excessive mandibular incisor flaring. Treatment Plan Due to the severity of the protrusion, maxillary and mandibular first premolars were extracted. The patient was banded with an 022 edgewise appliance. After one year of treatment, the mandibular third molars and maxillary first molars were extracted so that the Angle’s Class II dental relationship could be corrected without proclining mandibular incisors. The patient was treated, all spaces were closed, and the patient was placed in 45 Fig. 1. Pretreatment photographs. Fig. 2. Pretreatment casts. Fig. 3. Pretreatment panoramic radiograph. Hawley retainers at the cessation of treatment. Fig. 4a. Pretreatment cephalogram and 4b) tracing. Fig. 5. Pretreatment/posttreatment photographs. Fig. 6. Posttreatment casts. Fig. 7. Posttreatment panoramic radiograph. Posttreatment Records The pretreatment/posttreatment photographs (Fig. 5) confirm marked reduction in the bialveolar protrusion, lip strain has been eliminated, and the patient has a much more balanced and pleasing facial profile. The posttreatment casts (Fig. 6) exhibit correction of the dentition to a Class I dental relationship and a reduction in the protrusion. Maxillary third molars will erupt and take the place of the maxillary second molars which have been moved mesially. The posttreatment panoramic radiograph (Fig. 7) exhibits roots that are parallel in the extraction sites and the erupting maxillary third molars. The posttreatment cephalogram and its tracing (Fig. 8a, b) confirm maintenance of the vertical dimension, quite a bit of mandibular incisor uprighting, and an improved Z angle. The superimpostions (Fig. 9) illustrate intrusion and retraction of the maxillary anterior teeth and uprighting of the mandibular anterior teeth. The pretreatment/posttreatment smiles (Fig. 10) are testament to the treatment plan and to the treatment which was delivered. The patient was seen on recall and new casts were made. These casts (Fig. 11) confirm eruption of the maxillary third molars and a very functional dentition. The presentation of this case report exhibits the use of Tweed-Merrifield mechanics and what can be done for a patient who has a severe malocclusion - if the treatment plan is proper and if the force systems are delivered in a proper manner. Fig. 8a. Pretreatment cephalogram and 8b) tracing. 46 “Addendum” This patient had been treated twice prior to these records. The facial photographs (Fig. 12) show protrusion and lip strain. The pretreatment dental photographs exhibit an excellent Class I dental relationship, a very small amount of crowding, and a rather protruded smile. The cephalogram with IMPA and FMIA highlighted (Fig. 13) exhibits mandibular incisors that are at 100° to mandibular plane and a low FMIA. The protrusion is evident Fig. 9. Pretreatment/posttreatment superimpostions. The patient wanted retreatment. Maxillary and mandibular second premolars were removed. The posttreatment facial photographs and photographs of the teeth (Fig. 14) illustrate reduction of the protrusion and a nice Class I interdigitation of the teeth. The posttreatment cephalogram (not shown) confirmed that mandibular incisors were uprighted from 100° to 86° and the Fig. 10. Pretreatment/posttreatment smiles. Fig. 12. Pretreatment photographs. Fig. 11. Recall casts. Fig. 13. Pretreatment cephalogram. 47 FMIA improved from 58° to 69°. The final comparison of the facial profile (Fig. 15) is graphic evidence of what should be done when patients with bialveolar protrustions are properly treatment planned. The final recall photographs of teeth and face (Fig. 16) say a lot of things about where orthodontics should be going and what kind of service we can render to our patients if the treatment plan and the force systems are proper. Fig. 14. Posttreatment photographs. Fig. 15. Pretreatment/posttreatment/recall profile photographs. Fig. 16. Recall photographs. 48