Download Consensus Conference on the "New Tecnologies

Consensus Conference on the "New Tecnologies in Miniscrews & Miniplates”
Gianluigi Fiorillo DDS, MSc, Moderator [email protected]
Dieter Drescher DDS, MSc, Phd. [email protected]
Nelson Donald DDS, DMD. [email protected]
Carla Evans DDS,Msc, Phd. [email protected]
Francesco Grampone DDS, MSc. [email protected]
Fabio Labate DDS, MSc, Phd. [email protected]
Cesare Luzi DDS, MSc. [email protected]
Giuliano Maino DDS, MSc. [email protected]
Intoduction In recent years, the orthodontic scenario has been drastically transformed by
the introduction of an innovative procedure known as skeletal anchorage and, especially, the
use of miniscrews as biomechanical anchors. Not only may the latter replace all existing
anchorage instruments in orthodontics, but they may also allow overcoming current
limitations associated with the use of traditional tools. These include collapsing, unfavorable
anatomy, discomfort, damage and complexity of implementing procedures among others.
Contrarily to traditional anchorage devices, the use of miniscrews enables practitioners to
create customized biomechanical designs, reducing the need of surgery. These benefits
have been confirmed by the latest peer-reviewed scientific literature, including numerous
case studies. However, this revolutionary procedure is not yet widely executed due to a
variety of reasons. As the approach is yet to be mastered, professionals fear that the
technique may be invasive, causing a number of potential complications and side effects. As
a consequence, patients are rarely recommended this alternative. The following discussion
is based on the results of a questionnaire designed by leading experts in the field. The
paper aims to discard all emotional bias linked to this new method and provide clear
guidelines for its correct implementation.
Gianluigi Fiorillo In which clinical task do you most frequently use miniscrews in your
practice?
Dieter Drescher Molar distalization, molar mesialization, alignment of impacted teeth, molar
uprighting, molar intrusion, midline correction, rapid maxillary expansion, maxillary
protraction (early Cl. III treatment)
Carla Evans. I personally utilize TAD most frequently for skeletal transverse expansion,
typically when the patient displays periodontal bone loss or short dental roots (e.g., PapillonLefevre Syndrome). Palatal expansion can be achieved without using the teeth as anchors. 7
Using palatal miniscrews to anchor an expansion plate in conjunction with surgically-assisted
rapid palatal expansion.
Francesco Grampone Essentially, I use it in all cases where the force on the reactive unite
would generate adverse side effects. For instance, in cases of protraction or distalization of
posterior teeth, uprighting of mesially tipped molars, retraction of anterior teeth into
extraction spaces,intrusion of anterior incisor during gummy smiles correction, and extrusion
of canine teeth.
Fabio Labate Distalization , mesialization, molar intrusion especially in multidisciplinary
treatments in a part of an arch in adult patients and in cases of lack of cooperation in the use
of inter-arch elastics, reduced dental anchorage available.
Cesare Luzi There are two clinical problems that make me benefit from the use of TADS
routinely. The first is adults with partially edentolous ridges or periodontal problems. In these
cases anchorage can be difficult to setup if posterior teeth are missing or inconvenient if
teeth feature a compromised periodontium. In these cases skeletal anchorage opened new
horizons to our treatments. The second problem is maximum anchorage requirements.
Whenever I know that teeth have to be moved without any possible side effect on the
anchorage unit I decide to load the patient’s bone instead of his teeth.
Giuliano Maino I’m using mini screws very often in non-compliance cases regardless of the
different biomechanical needs and the required tooth movements. The malocclusions that in
my opinion are profiting most are Class II without extractions(18), hyperdivergent cases with
open bite tendency, Class III cases with maxillary retrusion, class II cases where a tentative
of mandibular growth stimulation it’s advisable, as well as adult multidisciplinary cases
especially where intrusion of overerupted teeth and molar Up-righting are required.
Donald Nelson Primarily, they are useful in establishing anchorage where needed, targeting
specific areas of the dentition to isolate anchorage needs [1]We now have options for
treating cases where cooperation is an issue [1]
TAD's can mimic the use of Class II elastics [2]They can be used in lieu of headgear for
distalization though they do not provide the orthopedic factor [3]They can be substituted for
protraction headgear by providing direct skeletal anchorage though again, some orthopedic
benefits may be lost [4].
Gianluigi Fiorillo With the use of miniscrews how did the need for other orthodontic
auxiliaries change?
Dieter Drescher Yes! With the use of TADs the headgear has become practically obsolete. 1
Using mini-plates in the mandible, extraoral devices for maxillary protraction in Cl. III are also
no longer needed.2,3 Mini-implants inserted in the anterior palate can be equipped with
special abutments to construct appliances for molar distalization, mesialization or intrusion.4
Carla Evans Utilization of miniscrews increases the range of malocclusions that can be
managed in an orthodontic practice. Previously, treatment plans for some orthodontic
problems either included an orthognathic surgery procedure or accepted a compromised
result, but now may be possible with assistance of miniscrews. Also, miniscrews may be
included in alternative treatment plans when a patient is not compliant with wearing
headgear or other orthodontic auxiliaries. These advances, however, do not allow the
orthodontist to forget the principles of biomechanics.
Francesco Grampone Using miniscrews I decreased the need for other orthodontic
auxiliaries. The possibility to anchor on the bone instead of on the teeth reduces the need for
extra-oral forces or the need for tools able to increase dental anchorage. I don’t use
auxiliaries to distalize teeth anymore.
Fabio Labate The use of headgears is almost eliminated.
Cesare Luzi The use of miniscrews can greatly diminish the need of traditional anchorage
auxiliaries such as transpalatal arches, lower lingual arches, head-gears, stainless steel
sectional archwires, etc. This on one side simplifies the orthodontist’s job making anchorage
more secure by loading the patient’s bone and not his teeth, avoiding detrimental side
effects, and on the other side reduces the overall “load” of the appliance making it more
confortable and acceptable for the patient.
Giuliano Maiono In my office, the use use of extraoral forces (cervical traction, high pull
traction) and class II elastics have been substantially reduced.
Donald Nelson At present, we have implemented miniscrews in the following clinical
scenarios: To create anchorage where needed for selected movements of distalization,
mesialization and lateral shifts. In addition, for support of SARPE in adults with compromised
buccal cortical bone support.
Gianluigi Fiorillo What are the ideal characteristics of a miniscrew (diameter, length, etc.)?
Dieter Drescher made of titanium alloy (Grade V), sufficient diameter, i.e. >= 1,6mm 20,
sufficient length, i.e. >= 7mm, self drilling thread, tapered or conic intra-osseous part, smooth
neck, versatile head.
Carla Evans In vivo studies in the literature have been confusing and contradictory.
However, finite element and laboratory studies have given us some clues about design of
anchor devices.1,2,5 Our 2012 paper in the Angle Orthodontist showed that some factors
affected the stresses in bone (implant diameter, implant head length, thread size, and elastic
modulus of cancellous bone), while other factors did not (intrabony implant length, thread
shape, thread pitch, and cortical bone thickness). Factors that affect stress levels are likely
to affect long-term stability.
Francesco Grampone Some authors show that screws of 8 mm in length and at least 1.2
mm in diameter have sufficient stability with a minimum risk of root damage. No risk
difference was found for self-tapping or self-drilling screws. When needed, particular care
needs to be taken with the pilot hole because its preparation could increase risk of failure.
For this reason and to avoid any surgical-related factors I prefer screws with self-drilling
extremity. I also recommend screws without trans-mucosal plate because it has been
showed that in cases of over-angulated insertion, useful to primary stability, the plate may
produce an ischemic gingiva on one side and an area of easy bacterial access on the other
side, increasing the risk of failure. The head design is important because it should guarantee
a full use, from a direct anchorage to an indirect anchorage.
Fabio Labate Monocortical, self-cutting, self-drilling, 8 x 1,7mm, bracket shaped head,
crossed slot 0.22.
Cesare Luzi Last generation miniscrews have some common important characteristics.
Overall length should be at least 9mm and not exceed 13mm, thread length should not be
less than 6mm to reduce the risk of loss of stability (6), neck lenghts should be in
relationship to the thickness of the soft-tissues (1-3mm). The diameter should not be inferior
to 1.2mm to avoid risk of fracture (4) and not exceed 1.6mm in order to be useful in interradicular sites. The point should have self-drilling characteristics and the thread cut should
be asymmetric and deep enough to increase stability preventing pullout (7).
Giuliano Maiono The ideal miniscerw should have the shortest length and the thinner
diameter with respect to the insertion site and the quality of bone available. However both
factors could vary depending from patient to patient. A greater increase in the diameter
appears to be linked to a higher amount of success(7). According to other studies, the length
of the implant is not very important to the success of a miniscerw(1)(8). In contrast (9)other
studies report that, using thin miniscrew , increasing the length will correspond to a greater
success rate(10)(11). Length and diameter of the miniscrew therefore should be chosen
according to the ammount of available bone, to the bone quality and specific anatomival
condition. Many studies have been carried out to compare the shape of the infrabony portion
of the mini screws. Some studies claim that the conical shape ensures greater primary
stability and this should translate into a greater amount of success (12) (13) (14).On the
other hand, when comparing the clinical success rate between conical and cilindrical
miniscrews, no difference has been found (15).
Donald Nelson Orthodontic miniscrews should be comprised of a titanium alloy without
surface treatment, as this would encourage osseointegration of the miniscrew [6].
It has been recommended that screw sizes less than 1.2 mm in diameter and 8mm in length
should be avoided [17, 18].
Gianluigi Fiorillo How much does the operator’s experience weigh on preventing the risk of
failure? How to prevent failure?
Dieter Drescher There are several ways to minimize failure rates of mini-implants:7-20Insert
mini-implant through the attached gingival or mucosa (oblique insertion), avoid root contact,
avoid excessive insertion torque, i.e. > 40 Ncm, assure sufficient insertion torque, i.e. > 5
Ncm, avoid mini-implants with too small diameter, i.e. >= 1.6 mm, in the maxilla: prefer the
anterior palate, avoid the alveolar ridge, in the mandible: avoid the front segment of the
dental arch, instruct the patient how to provide sufficient oral hygiene, monitor oral hygiene,
avoid axial moments as well as too large tipping moments, use two coupled implants
(tandem).
Carla Evans We studied factors associated with initial stability of miniscrews. 4 Site of
insertion and experience of the clinician were the only significant variables. The midpalatal
area was the most suitable for initial stability. Clinicians who performed more than 20
miniscrew insertions had a higher success rate than those with less than or equal to 20
insertions, even after adjusting for insertion site. The potential confounding patient and
device variables examined were gender, age, jaw, insertion site, tissue type, length and
diameter of the miniscrew, and number of previous insertions. Though not studied in our
research, it is possible that long- term stability may be related to quality of bone and other
factors.
Francesco Grampone With screws as well as any other tool, clinical experience reduces
the incidence of failures. In particular, learning curve influences surgery-related factors such
as flap procedures, hole preparation, and jiggling placement procedures. In order to avoid
failure, it’s also important to follow the the orthodontics-related guidelines, for instance by
preferring immediate load to delayed load or by using force levels up to 200 g avoiding
unscrewing movements.
Fabio Labate The operator’s experience has a little impact on the prevention of failure if the
procedures are being followed and the patient is appropriately informed once the insertion
site is properly detected.
Cesare Luzi Miniscrews fail due to problems related to the patient or problems related to the
clinician (1). Patient-related factors involve mainly bone quality, oral hygiene, soft-tissues
characteristics and other minor factors. The main clinician-related problem is an incorrect
insertion procedure. Experience plays a very important role in the overall failure rates as lack
of primary stability due to an incorrect insertion procedure or an unfavorable insertion site
(lack of proper distance fron the adjacent roots or poor bone quality) is a common problem.
A learning curve is required to prevent failure as much as possible, although 100% success
in never possible and does not appear in the literature (2).
Giuliano Maiono According to many studies, there is a learning curve in the miniscerw
insertion that will affect the percentage of success and failure. To prevent failures, the
clinician should provide a good radiographic survey prior to the application of a miniscrew. If
the miniscrew is inserted in the interproximal spaces, I suggest to use a periapical x ray
performed with the parallel technique to avoid bias and to have reliable measurements.
Panoramic X ray can be used in presence of wide spaces due to the enlargement of this
type of examination. Another option is the use of a CBCT scan. It is also advisable the use
of a surgical guide83)(4) especially if the the miniscrew insertion will be performed in difficult
areas and narrow spaces, and if the experience of the operator is limited.
Donald Nelson Failure and success rates are highly correlated to the clinical skill and
experience of the operator who places the miniscrew. Achieving primary stability appears to
be the most important determinant for the success of the miniscrew. Insufficient primary
stability will lead to deficient healing and the premature loss of the miniscrew [13]. In
regards to insertion procedure, the initial force of placement should be performed with
moderate force and once the initial threads have penetrated the cortical bone, allow the
miniscrew to draw itself in [14]. Wiggling/wobbling action of the miniscrew while inserting
should also be avoided.
Gianluigi Fiorillo Which failure factors are patient-dependant and cannot be prevented?
Dieter Drescher Poor oral hygiene21 Manipulation by patient.
Carla Evans I wouldn’t put miniscrews in patients who are moderate-to-heavy smokers,
have poor oral hygiene, or have increased susceptibility to infection. Also, it is possible that a
patient’s physician may determine that placement of miniscrews is contraindicated due to
certain medical or psychological conditions. All orthodontic treatment for patients with
significant medical or psychological disorders should be undertaken only after consulting
with the patient’s physician(s).
Francesco Grampone Patient-dependent factors such as those realted to the quality and
quantity of cortical bone and the quality and quantity of keratinized gingiva cannot be
prevented. Preventable but unfavorable factors are smoking, use of bisphosphonates, and
poor oral hygiene.
Fabio Labate Hygiene, traumatic nutrition, bone metabolism.
Cesare Luzi The main patient-dependant failure factor is poor bone quality. Proper cortical
bone thickness should exceed 1mm (3) in order to reduce risk of loss of stability. Posterior
areas, especially in the mandible, meet this criteria. Anterior areas are more at risk, and also
high-angle patients (4). A second factor that influences negatively failure is the presence of
thick soft-tissues (5), like in the palatal sites or the lower retro-molar area. Keratinized
attached soft tissues should always be preferred when possible. A third negative factor is
poor oral hygiene, promoting inflammation of the tissues surrounding the screw head and
neck. Proper attention to oral hygiene daily procedures should be well discussed and the
patient should be properly instructed.
Giuliano Maiono The bone quality is not clearly predictable expecially in growing patients
where we could face a wide range of bone density. It’s well known that the bone quality will
affect the miniscrew stability(6) and in presence of a soft kind of bone we could expect more
failures.
Donald Nelson The following are patient-dependent influencing the success or failure of
miniscrews [15]:
Plaque and gingivitis indices, oral hygiene, smoking, metabolic disorders such as diabetes or
osteopoenia which influences bone density [16]
Gianluigi Fiorillo How to prevent root damage?
Dieter Drescher The best way is to avoid insertion of mini-implants into the alveolar ridge,
which is easily possible in the maxilla.4 In the mandible use of mini-plates instead of miniimplants has to be considered.22If mini-implants are to be inserted into the alveolar ridge, a
panoramic X-ray of good quality is obligatory. A distance of at least 1mm between the
implant and the adjacent roots is recommended.10
Carla Evans Experienced clinicians examine closely the pre-treatment records. They then
determine an adequate angle of insertion (i.e. generally oblique at 20-40 degrees) and then
maintain that angle during screw insertion.
Francesco Grampone Clinical examination and appropriate analysis of the plaster casts as
well as of theradiographs can prevent any root damage. In particular, 3D-based radiographic
analysis is the best solution. However, if it’s unavailable, panoramic x-ray and periapical
radiographs are adequate to evaluate the root positions. Eventually, to avoid roots, I take a
periapical radiograph during surgery. An additioinal sign of being too close to the root may
come the patient complaining of intra-procedural pain. Using a superficial anesthesia the
patient will feel pressure, but not pain, unless the screw contacts the periodontal ligament or
the tooth root. In this case, it is useful to change the angle of insertion angle or eventually
the insertion site.
Fabio Labate Radiographic evaluation of the site after doing the dental allignment or use of
passive wires on the teeth adjacent to the miniscrews, mucose topical anesthesia, manual
tightening.
Cesare Luzi Root damage is a possible complication if the insertion procedure is not
planned correctly. It is an unlikely event to generate permanent damage as healing of the
periodontium following contact or approximation of the miniscrew with the roots followed by
screw removal has been extensively demonstrated (8). The most important phase is the
selection of the insertion site following clinical and periapical radiographs parameters. A
minimum of 4mm clearance between the roots is necessary to reduce risks. During insertion
attention should be payed to possible increases of resistance during the procedure which
could be an indicator of root contact. Post-insertion periapical radiographs should always be
taken. In case of doubt and in presence of pain following the anestesia effect, the miniscrew
should be removed and replaced.
Giuliano Maino A thorough X Ray investigation, meticulous clinical evaluation, small
amount of anesthetic, the use of a surgical guide and a proper clinical training are the main
factor to avoid root damage when inserting miniscrews. It could be usefull remember that, in
the case of root contact with the miniscrew, the root surface will repair similary to the
resorption areas that may be ecountered during a regular orthodontic treatment(16)(17).
Donald Nelson To prevent root damage, the clinician should be fully aware of the
interradicular space for the intended miniscrew placement.
The area should be
radiographically assessed before proceeding. The miniscrew size should be selected as to
placed at least 1mm away from adjacent roots [18]
Gianluigi Fiorillo Did 3D diagnostics change planning procedures for miniscrew insertion?
Dieter Drescher CBCT can be used for planning mini-implant insertion23, but given the
radiation exposure is it questionable if it is really justified.
Carla Evans We recently published guidelines for use of CBCT in orthodontic treatment. 6
We cited numerous authors who identified CBCT imaging as being clinically useful in
identifying optimal site placement of orthodontic miniscrews. Clinicians are instructed to: “1.
Image appropriately according to clinical condition, 2. Assess the radiation dose risk, 3.
Minimize patient radiation exposure, and 4. Maintain professional competency in performing
and interpreting CBCT studies.”
Francesco Grampone 3D didn’t change planning procedures but increased it success rate
because at radiation exposure very similar to that of panoramic you can have greater and
more precise informations. In fact, with CBCT you can evaluate position, distance, root
divergence and bone thickness in all the planes of the space. Unfortunately, it is not always
possible to use this tool because of its associated costs.
Fabio Labate The assessment of cortical thickness surely affects significantly the choice of
the site of insertion of miniscrews, but if the CBCT is performed only for this I think is an
overtreatment.
Cesare Luzi 3D diagnostics changed the way we look at our patients in many situations.
Planning miniscrew insertion is not one of them. In my opinion the request of a 3D scan is
not justified, due to radiation dose and costs for the patient, unless there are doubts on the
anatomy that 2D traditional radiographs cannot make clear. A standard protocol requires
only the use of parallel periapical films.
Giuliano Maino The use of 3D X Ray investigation makes easier the case analysis and in
some specific situation also the planning of the miniscerw insertion especially in areas
difficult to investigate with conventional (2D) radiologic techniques such as the palatal vaulte
and the mandibular region in correspondence with the oblique line(4).
Donald Nelson Cone beam computed tomography (CBCT) could serve as a useful adjunct
that could identify more precisely the proximity of vital areas such as the maxillary sinus and
major nerves. In addition, the interradicular bone mass could be made. Surgical stents can
also be fabricated from the imaging [19].
Gianluigi Fiorillo Is it necessary to perform local or systemic antibiotic?
Dieter Drescher Systemic antibiotic prophylaxis can be useful when inserting mini-plates.
For the insertion of mini-implants administration of systemic antibiotics is not needed.In the
case of mild peri-implant inflammation or mucosal hyperplasia local CHX application can be
recommended.
Carla Evans When the health history reveals cardiovascular disease or other disorders that
might predispose a patient to infective endocarditis, or when a patient reports a total joint
replacement, it’s important to contact the patient’s physician and determine together whether
antibiotic prophylaxis is needed. We follow the American Dental Association and the
American Heart Association guidelines.
Francesco Grampone Prescription of antibiotics is not recommended unless there are
specific medicalindications.
However, local prophylaxis is needed with the surgical protocol.
Good oral hygiene is the most important factor. Chlorexidine mouthrinses (0,20%) for 30
seconds before surgery allows for reduction of local antimicrobial activity.
Fabio Labate No, local disinfection is sufficient.
Cesare Luzi There is absolutely no need for antibiotic prophylaxis. The last generation selfdrilling/self-tapping miniscrews require a minimally invasive trans-mucosal insertion
procedure. There is never the need to perform flap surgery, bleeding is absent or extremely
limited and the bur (rotating instrument) is used only in sites with thick cortex (i.e. lower retromolar region). Pain-killers could be suggetsed, although the need is patient-dependant, while
chlorexidine mouthwash is recommended for one week post-insertion during the healing of
the soft-tissues.
Giuliano Maino No, it’s not necessary. I do it only in patients where needed for general
conditions.
Donald Nelson Local antibiotic applied to the implant site is recommended. With miniscrews patients are asked to apply chlorhexedine with a cotton swab daily to tissue around
the screw head [6] [7]. With mini-plates, the oral surgeon will generally prescribe systemic
antibiotics following the procedure, however it is questionable that it is absolutely necessary
[8]
Gianluigi Fiorillo What kind of anesthesia is recommended?
Dieter Drescher Local and optionally topic anaesthesia is sufficient for mini-implant
insertion.5 Removal of mini-implants usually needs no anaesthesia.6
Carla Evans Traditional local infiltration methods are effective for miniscrew placement both
in the alveolar process and the palate. We studied two topical anesthetics for placement in
the maxillalry and mandibular alveolar processes, Oraqix and TAC alternative3. Oraqix, an
FDA-approved topical anesthetic gel for scaling, root planing (SRP) and gingival curettage
contains 2.5% lidocaine and 2.5% prilocaine. TAC(a) is a compound mixture of 20%
lidocaine, 4% tetracaine, and 2% phenylephrine. Based on the dosage, onset time, the
patients’ responses on pain scales, and observation of their subjects’ SEM (sound, eye,
motor) movements, we concluded that TAC(a) is a more effective topical anesthetic during
the placement of TADs than Oraqix. We recommended that 0.20–0.30 mL of TAC(a) be
applied for a minimum of 3 minutes. Patients should always be queried whether they have
had an adverse reaction to anesthetics.
Francesco Grampone In accordance to the current literature I don’t use deep anesthesia. I
deliver the anesthetic only to surrounding soft and periosteal tissue. In this way, when the
screws are applied, patients will only experience some pressure. Pain may occur if the screw
contacts the periodontal ligament or the tooth roots. Thus, the insurgence of pain represents
an important sign for the clinician to avoid root damage. I use topic anesthetic gel or local
anesthetic spry before the local infiltration of Lidocaine.
Fabio Labate Mucose topical
anesthesia.
Cesare Luzi The ideal would be to give to the patient the minimal possible quantity of
anesthesia in order to affect the soft tissues and the periosteum, with minimal effect on the
deep tissues (PDL and teeth). This way the patient would feel pain if the tip of the miniscrew
would reach proximity to the PDL and tooth. Local anesthesia is always recommended with
an infiltarative technique, both in the maxilla and in the mandible. Topical spray anesthesia is
the alternative, but might not be always effective to avoid patient pain during insertion.
Giuliano Maino We could use gel with high percentage of anesthetic (Lidocain 30%) in
areas with thin soft tissues. I prefer tissue infiltration with a minimum amount of anesthetic .
I’m using Lidocain with adrenalin 1:100.000. It’s important to use a little amount of
anesthetic in order to leave intact the dental sensitivity.
Donald Nelson In many cases, a potent pharmacy prepared topical is sufficient. Our current
formulation used is as follows: 10% Lidocaine, Prolocaine 10%, Tetracaine 4% and
Epinephrine 2% [5].
Gianluigi Fiorillo Are there any problems with the use of miniscrews in growing patients?
Dieter Drescher The failure rate seems to be slightly higher in growing patients.24
Carla Evans Miniscrews may be contraindicated in growing patients with unerupted teeth
because there may be insufficient space for the miniscrew.
Francesco Grampone Studies show a lower success rate with adolescents because of
insufficient bone density. They also suggest to avoid the use of screws in patients under 11
years of age. However, I have successfully treated teenagers with miniscrews in the palatal
area without failure. In growing patients, take care during screw insertion to avoid positioning
the screws in areas of permanent tooth development.
Unfortunately, I have no experience with the use of miniscrews with orthopedic force.
Fabio Labate Certainly those related to the buds of not erupted permanent teeth, the
decrease of cortical thickness and at the lesser compliance (hygiene, nutrition).
Cesare Luzi TADS are orthodontic tools that by definition are “temporary” and are generally
removed after some months of use as soon as the orthodontist changes treatment phase.
The orthodontic load generates continuous tissue remodelling around the screw (9) and the
smooth untreated surface makes removal generally very simple. The use of TADS in
growing patients is absolutely not a problem. The only risk is leaving a miniscrew in place
several months without loading it, promoting osseointegration. In this case removal could be
more problematic (10).
Giuliano Maino Right now there is no study advising against the use of miniscrews in
growing patients.
Donald Nelson Currently, there is equivocal data on the use of miniscrews in growing
patients. It has been previously reported that higher failure rates occurred in growing
patients attributed to lesser bone densities’ and cortical thickness [20]. However, in regards
to orthopaedic traction in growing patients, some success has been reported in growing
skeletal class II and Class III growing patients [21] [22]
Gianluigi Fiorillo Who should insert miniscrews, the orthodontist or the surgeon?
Dieter Drescher Preferably the orthodontist (personal opinion)..
Carla Evans Insertion of miniscrews in the alveolar process and palate falls within the scope
of orthodontic practice. In those situations, the orthodontist is best able to judge the optimal
placement for executation of the planned mechanics. An orthodontist who prefers to refer the
placement of TADs in the alveolar process or palate could refer either to a periodontist or
oral surgeon. Temporary anchor devices placed in the mandibular ramus or zygomatic arch
should be handled by an oral surgeon.
Francesco Grampone I place my own miniscrews and I personally think orthodontists are
recommended to do it because othodontists know exactly where the screws should be
placed. Moreover, if more than one dentist is involved with the procedure and the treatment
fails, it could be difficult to find out who is responsible for the failure.
Fabio Labate The orthodontist, if the insertion doesn’t require flap (if it’s a flap-less
insertion).
Cesare Luzi The orthodontist is the best candidate for miniscrew insertion. The procedure is
a very simple flapless surgery that does not require particular surgical skills. The orthodontist
knows exactly the use he has planned for the miniscrew, the details of the treatment plan,
the programmed biomechanics and the final position of the teeth which is planned at
treatment start. He will therefore choose the best available insertion site consistent with the
following upcoming tooth movements. Miniscrews should be considered tools for
orthodontists, not forsurgeons.
Giuliano Maino It’s largely accepted that miniscrews should be applied directly by the
orthodontist. In fact the site of miniscrew insertion is selected not only on the basis of
anatomic space availability but it’s also dictated from the biomechanics needs. Further more,
doing like this, the miniscrew insertion become simple for the pazient also in terms of time
saving.
Donald Nelson Either, but if the mini-screw is placed by the oral surgeon, the site should be
carefully targeted by the orthodontist to facilitate optimal mechanics [9]
Gianluigi Fiorillo Which is the best way to propose to the patient the use of miniscrews?
Dieter Drescher Explain to the patient, why skeletal anchorage is useful. Extraoral traction
can be avoided.
Carla Evans After developing specific treatment objectives based on high quality records
and known effectiveness of different treatment modalities, I would explain my preferred
treatment plan to the patient. I would state that treatment plans utilizing miniscrews have
been shown to be safe and predictable. If the patient requires more information, I wouldn’t
hesitate to supply relevant published articles. I also encourage patients to see second
opinions.
Francesco Grampone The best way to propose the use of the miniscrews to the patient is
to believe in it. Too many are the advantages of using miniscrews .The possibility to reduce
treatment time and avoid anchorage on the natural dentition is the most effective argument
to convince our patients.
Fabio Labate Proposing if possible an alternative with the use of other auxiliaries the
obtainable result without their use, emphasizing the longer duration of the therapy and
greater need of cooperation.
Cesare Luzi Personally, when speaking to patients and parents, I refer to miniscrews as
orthodontic temporary gingival “piercings” or small gingival “pins” used to control possible
side-effects of the treatment mechanics. I never use the word “screw” or “implant” which tend
to make the patient think of invasive surgical procedures. Furthermore, I stress the fact that
TADS are new generation devices made on purpose for orthodontists and are becoming
daily tools. This simple language helped me very much to comunicate to patients and
parents the benefits of TADS without generating refusals or fear of the tool.
Giuliano Maino I suggest to carefully explain to the patient what kind of benefits he can
expect from a non-compliance treatment, including avoidance of the use of extra-oral
devices, Class II elastics a. Then underline the greater predictability of outcome with respect
to a treatment where collaboration is uncertain or is in missed. Finally i twill be explained to
the patient that inserting a temporary anchorage miniscrews is a minimally invasive
procedure and much less unconfortable in comparision to an extraction of a premolar i.e. In
50% of cases it does’ n cause any pain at a distance of one hour. In 90% of cases there will
be no pain the day after(1). Everithihng can be controlled with a simple analgesic.
Donald Nelson Patient education is fundamental for a patient’s acceptance to the use of
miniscrew placement. The following is recommended to be included in the dialogue with the
patient:
The use of the miniscrews may permit for orthodontic movements to occur which otherwise
could not be obtained therefore allowing the orthodontist to obtain a more ideal treatment
result for the patient.
The miniscrew, which is very discreet, painless and easy to insert would eliminate the need
for more bulky and cumbersome hardware.
Always show the patients the anchorage options (nance, headgear, etc.) and allow them to
decide between the miniscrew or the alternatives.
Allay any fears or anxiety to the procedure the patient may have as the patient’s acceptance
is strongly influenced by pain and discomfort [12].
Gianluigi Fiorillo Which specific characteristics does the Informed Consent format require?
Dieter Drescher Depends on local legislation. In Germany the most common possible side
effects have to be mentioned: inflammation, mplant loss, root contact, if TADs are inserted
into the alveolar ridges.
Carla Evans The American Association of Orthodontists8 has two consent documents for
TADs; they are found on the AAO Insurance Company website (www.aaoic.com). One is
contained within the general consent for orthodontic treatment. The other is a separate
supplemental form that gives similar information and, in addition, requires the patient to
disclose tobacco use. I agree with the content of both and feel strongly that the patient must
be informed of the risks. The AAO’s general consent form states: “Your treatment may
include the use of a temporary anchorage device(s) (i.e. metal screw or plate attached to the
bone.) There are specific risks associated with them. It is possible that the screw(s) could
become loose which would require its/their removal and possibly relocation or replacement
with a larger screw. The screw and related material may be accidentally swallowed. If the
device cannot be stabilized for an adequate length of time, an alternate treatment plan may
be necessary. It is possible that the tissue around the device could become inflamed or
infected, or the soft tissue could grow over the device, which could also require its removal,
surgical excision of the tissue and/or the use of antibiotics or antimicrobial rinses. It is
possible that the screws could break (i.e. upon insertion or removal.) If this occurs, the
broken piece may be left in your mouth or may be surgically removed. This may require
referral to another dental specialist.When inserting the device(s), it is possible to damage the
root of a tooth, a nerve, or to perforate the maxillary sinus. Usually these problems are not
significant; however, additional dental or medical treatment may be necessary. Local
anesthetic may be used when these devices are inserted or removed, which also has risks.
Please advise the doctor placing the device if you have had any difficulties with dental
anesthetics in the past. If any of the complications mentioned above do occur, a referral may
be necessary to your family dentist or another dental or medical specialist for further
treatment. Fees for these services are not included in the cost for orthodontic treatment.”
Francesco Grampone The informed consent has to specify that insertion and dis-insertion
involves a minimally invasive surgical approach and need for post-operative care. The
patient has to be informed about the possibility of failure or fracture. Furthermore, in the
event that a screw fracture occurs, the patient needs to consent about the need to follow the
dentist judgment on whether the screw will have to be removed or left in place.
Fabio Labate The Informed Consent must be detailed and understandable/clear as with any
other procedure.
Cesare Luzi The Informed Consent should explain clearly what is a Temporary Anchorage
Device, the reasons and the advantages of the use of TADS and the possible risks
associated to the procedures. It should be clearly stated that TADS are orthodontic
anchorage tools and have nothing to do with traditional implants and with the risks
associated to the use of these last devices.
Giuliano Maino It should contain a clear explanation that the miniscrew is a temporary
anchorage device perfectly biocompatible and that its insertion requires the use of a
minimum amount of anesthetic. It should also be specified that the miniscrew sometimes can
become mobile and in those cases must be repositioned. It should be emphasized the need
for careful hygiene worth the failure of the implant. Among the possible complications we
must mention the rare possibility that it could be experienced a fracture of the mini implant.
In that case, accoding to the clinical needs, the miniscrew can be removed or left in place.
Donald Nelson The standard informed consent released from the American Association of
Orthodontists (AAO) includes the following possible complications [10]: Loosening of the
miniscrews that would require their removal subsequent replacement/relocation.
Accidental swallowing of screw and related material. Inflammation or infection of surrounding
tissue leading to soft tissue overgrowth which would be managed surgically or palliatively
with antibiotics. Breakage of screws that may require referral to another dental specialists.
Damage to adjacent root, nerve or perforation of maxillary sinus which may necessitate
additional dental/medical treatment. Associated risks from the local anesthetic used to
increase patient comfort while inserting miniscrews. In addition, it may be noted that the
goals of the mini-screw may not be met.
Gianluigi Fiorillo Is traditional insurance policy for orthodontist covering the risks of
miniscrew usage?
Dieter Drescher In Germany: the insurance policy has to be updated, which was no
problem in my case.
Carla Evans Insertion and utilization of miniscrews falls within the realm of orthodontic
practice and insurance coverage from The American Association of Orthodontists Insurance
Company includes miniscrew usage. Other dental insurance companies may compute the
cost of their plans based on the degree of clinical intervention and the degree of anticipated
risk. Orthodontists who plan to utilize TADs and lasers should read the insurance policies
carefully before purchasing insurance.
Francesco Grampone In contrast to implant surgery, the use of miniscrews does not need
specific insurance coverage because it’s evident that the characteristics of the screws are
different from those of the osteointegrated implants. Further, the surgical risk is different
during implant insertion and screw failure cannot be considered like implant
failure.Moreover, if our insurance covers the root damage that could result from the
orthodontic over-forces, why wouldn’t it cover for the risks associated to the use of
miniscrews?
Fabio Labate The traditional insurance policy “without implants” is enough especially if
miniscrews are considered as orthodontic auxiliary.
Cesare Luzi The traditional insurance coverage for orthodontists, which does not include the
risks of implant surgery, has to mention clearly by the addition of an appendix that TADS,
orthodontic Temporary Anchorage Devices, and the possible risks associated with their use,
are included in the insurance agreement. This should not determine an increase in the
insurance yearly fee as no traditional implant procedure for rehabilittion purposes should be
mentioned or included in the agreement.
Giuliano Maino It seems that this type of limited insurance is not enough. It’ advisable
therefore to extend the insurance policy to the use of miniscerws that be defined as mini
implants.
Donald Nelson According to American Association of Orthodontists insurance company
(AAOIC), the placement of miniscrews is not considered a
surgical procedure and therefore provides coverage for the risks involved in their usage [11].
However, it should be noted that since the AAOIC does not provide coverage for surgical
procedures, miniplates insertion that would require a surgical flap would not be covered
under their policy.
References Suggest by Evans Carla
1.
2.
3.
4.
5.
6.
7.
8.
Lee ES, Evans CA, de Rijk WG. A finite element analysis of an HA-coated
titanium onplant on bone. In: Dental Materials Group, IADR, SP Schaffer, ed.,
IVOCLAR North America Inc., Amherst NY, 1997.
Hassan AH, Evans CA, Zaki AM, George A. The use of bone morphogenetic
protein-2 and dentin matrix protein-1 to enhance the osteointegration of the
onplant system. Calcified Tissue Research 44:200-210, 2003.
Kwong TS, Kusnoto B, Viana G, Evans CA, Watanabe K. The effectiveness of
Oraqix® versus TAC(a) for placement of orthodontic temporary anchorage devices.
Angle Orthod 81:754-9, 2011.
Lim H-J, Choi Y-J, Evans CA, Hwang H-S. Predictors of initial stability for
orthodontic miniscrew implants. Eur J Orthod 33:528-32, 2011.
Duaibis R, Kusnoto B, Natarajan R, Zhao L, Evans C. Factors affecting stresses
in cortical bone around miniscrew implants. Angle Orthod 82:875-880, 2012.
American Academy of Oral and Maxillofacial Radiology – Panel (Evans CA, CoChair). Clinical Recommendations Regarding Use of Cone Beam Computed
Tomography (CBCT) in Orthodontics. Position Statement by the American
Academy of Oral and Maxillofacial Radiology. Oral Surg Oral Med Oral Pathol
Oral Radiol Endod 116:238-257, 2013.
Vanarsdall RL, Blasi I, Evans M, Kocian P. Rapid maxillary expansion with
skeletal anchorage vs bonded tooth/tissue born expanders: a case report
comparison utilizing CBCT. Clinical Review (RMO), April 2012, pp. 17-22.
American Association of Orthodontists Insurance Company (www.aaoic.com).
AAO Informed Consent documents.
References suggest by Grampone Francesco
1. Kanomi R. Mini-implant for orthodontic anchorage. J Clin Orthod 1997; 31: 763-7
2. Costa A., Raffaini M., and Melsen B.. Miniscrews as orthodontic anchorage: A
preliminary report, Int. J. Adult Orthod. Orthog. Surg. 1998; 13: 201-209.
3. Cope J. Temporary anchorage devices in orthodontics: a paradigm shift. Semin Orthod
2005; 11: 3-9.
4. Labanauskaite B, Jankauskas G, Vasiliauskas A, Haffar N. Implants for orthodontic
anchorage. Meta-analysis. Stomatologija 2005;7:128-32.
5. Carano et co. Mechanical proprieties of three different commercially avaible miniscrews
for skeletal anchorage. Progress ortho 2005; 6 (1): 82- 97
6. Chen CH, Chang CS, Hsieh CH, Tseng YC, Shen YS, Huang IY, et al. The use of
microimplants in orthodontic anchorage. J Oral Maxillofac Surg 2006; 64:1209-13.
7. Mah J, Bergstrand F. Temporary anchorage devices: a status report. J Clin Orthod
2005; 39 (30) : 132-6.
8. Dalstra M, Cattaneo PM, Melsen B. Load transfer of miniscrews for orthodontic
anchorage. Orthod 2004; 1 (31): 53-62.
9. Lim JW, Kim WS, Kim IK, Son CY, Byun HI. Three dimensional finite element method for
stress distribution on the length and diameter of orthodontic inistre and cortical bone
thickness. Kor J Orthod 2003; 33:11- 20
10.
Melsen B., Costa A.. Immediate loading of implants used for orthodontic anchorage.
Clin Orthod Res 2000; 3(1): 23-28
11.
Cope J., Herman R., Miniscrew Implants: IMTEC Mini Ortho Implants. Semin Orthod
2005; 11: 32-39
12.
Reynders, Ronchi, and Bipat. Mini-implants in orthodontics: A systematic review of
the literature. American Journal of Orthodontics and Dentofacial Orthopedics May
2009; 564-68
13.
Costa A., Maric M., Danesino P.. Comparison between two orthodontic skeletal
anchorage devices: osseointegrated implants and miniscrews – Medical-Legal
Considerations. Progress in Orthodontic 2006; 7(1): 24-31
14.
Papadopoulos M.A., Tarawneh F.. The use of miniscrew implants for temporary
skeletal anchorage in orthodontics: a comprehensive review. Oral Surg. Oral Med
Oral Pathol Pral Radiol Endod 2007; 103 (5): 6-15.
15.
Crismani A., Berti M., Celar A., Bantleon H.P., Burstone C.. Miniscrews in
orthodontic treatment: review and analysis of published clinical trials. Am J Orthod
Dentofacial Orthop 2010; 103 : 108-11.
References suggest by Luzi Cesare
1. Luzi C, Verna C, Melsen B. Guidelines for success in placement of orthodontic miniimplants. J Clin Orthod. 2009 Jan;43(1):39-44.
2. Schätzle M, Männchen R, Zwahlen M, Lang NP. Survival and failure rates of orthodontic
temporary anchorage devices: a systematic review. Clin Oral Implants Res 2009;20:1351-9
3. Cattaneo PM, Dalstra M, Melsen B. Analysis of stress and strain around orthodontically
loaded implants: an animal study. Int J Oral Maxillofac Implants. 2007 Mar-Apr;22(2):213-25.
4. Miyawaki S, Koyama I, Inoue M, Mishima K, Sugahara T, Takano-Yamamoto T.
Factors associated with the stability of titanium screws placed in the posterior region for
orthodontic anchorage. Am J Orthod Dentofacial Orthop. 2003 Oct;124(4):373-8.
5. Luzi C, Verna C, Melsen B. A prospective clinical investigation of the failure rate of
immediately loaded mini-implants used for orthodontic anchorage.
Prog Orthod. 2007;8(1):192-201.
6. Mortensen MG, Buschang PH, Oliver DR, Kyung HM, Behrents RG.
Stability of immediately loaded 3- and 6-mm miniscrew implants in beagle dogs--a pilot
study. Am J Orthod Dentofacial Orthop. 2009 Aug;136(2):251-9.
7. Migliorati M, Benedicenti S, Signori A, Drago S, Cirillo P, Barberis F, Silvestrini Biavati A.
Thread shape factor: evaluation of three different orthodontic miniscrews stability. Eur J
Orthod. 2013 Jun;35(3):401-5.
8. Kim H, Kim TW. Histologic evaluation of root-surface healing after root contact or
approximation during placement of mini-implants. Am J Orthod Dentofacial Orthop. 2011
Jun;139(6):752-60.
9. Luzi C, Verna C, Melsen B. Immediate loading of orthodontic mini-implants: a
histomorphometric evaluation of tissue reaction. Eur J Orthod. 2009
10.Suzuki EY, Suzuki B. Placement and removal torque values of orthodontic miniscrew
implants. Am J Orthod Dentofacial Orthop. 2011 May;139(5):669-78.
Reference suggest by Giuliano Maiono
1. Clinical use of miniscrew implants as orthodontic anchorage: Success rates and
postoperative disconfort. Kuroda S., Sugawara Y., Deguchi T., Kyung HM., TakanoYamamoto T. Am. J. Orthod. Dentofacial. Orthop. 2007; 131:9-15
2. Predictors of initial stability of orthodontic miniscrew implants.Lim HJ, Choi YJ,
Evans CA, Hwang HS. Eur J Orthod. 2011 Oct;33(5):528-32
3. The spider screw for skeletal anchorage. Maino BG, Bednar J, Pagin P, Mura P. J
Clin Orthod. 2003 Feb;37(2):90-7.
4. Orthodontic miniscrew failure rate and root proximity, insertion angle, bone contact
length, and bone density.
Watanabe H, Deguchi T, Hasegawa M, Ito M, Kim S,
Takano-Yamamoto T. Orthod Craniofac Res. 2013 Feb;16(1):44-55.
5. Correlation between miniscrew stability and bone mineral
density in orthodontic
patients.
Santiago RC, de Paula FO, Fraga MR, Picorelli Assis NM, Vitral RW. Am
J Orthod Dentofacial Orthop. 2009 Aug;136(2):243-50
6. Osseous adaptation to continuous loading of rigid endosseous implants. Roberts
WE, Smith RK, Zilberman Y, Mozsary PG, Smith RS. Am J Orthod. 1984
Aug;86(2):95-111.
7. Factors associated with the stability of titanium screws placed in the posterior region
for orthodontic anchorage.
Miyawaki S, Koyama I, Inoue M, Mishima K, Sugahara
T, Takano-Yamamoti T.Am J Orthod Dentofacial Orthop. 2003; 124:373-378.
8. Park HS, Jeong SH, Kwon OW.
Factors affecting the clinical success of screw
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
implants used as orthodontic anchorage. Am J Orthod Dentofacial Orthop. 2006;
130:18-25
Clinical factors correlated with the success rate of miniscrews in orthodontic
treatment. Topouzelis N, Tsaousoglou P.
Int J Oral Sci. 2012 Mar;4(1):38-44.
The use of microimplants in orthodontic anchorage
Chen CH, Chang CS, Hsieh
CH, Tseng YC, Shen YS, Hang IY, Yang CF, Chen CM. J Oral Maxillofac Surg
2006; 64 (8): 1209-13
Success of miniscrews used as anchorage for orthodontic treatment: analysis of
different factors. Giuliano Maino B, Pagin P, Di Blasio A. Prog Orthod. 2012
Nov;13(3):202-9.
Hystomorphometric and mechanical analyses of the drill-free screw as orthodontic
anchorage. Kim JW, Ahn SJ, Chang YI
Am J Orthod Dentofacial Orthop 2005; 128:
190-4
Primary stability of micorscrews based on their diameter, lenght, shape and area of
insertion. an experimental study with periotest
Orquin M, Molina A, Puigdollers
A.
Prog in Orthod, 2008, 9 (2), 82-88
Impact of implant design on primary stability of orthodontic mini-implants Benedict
Wilmes, Stephanie Ottenstreuer, Yu-Yu Su, Dieter Drescher J. Orofac. Orthop.
2008; 69: 42-50
Comparison of Stability between cylindrical and conical type mini-implants JongWan Kim, Seung-Hak Baek, Tae-Woo Kim, Young-II Chang
Angle Ortod 2008; 78
(4)
Root damage and repair after contact with miniscrews. Maino BG, Weiland F,
Attanasi A, Zachrisson BU, Buyukyilmaz T. J Clin Orthod. 2007 Dec;41(12):762-6
Contact damage to root surfaces of premolars touching miniscrews during
orthodontic treatment. Kadioglu O, Büyükyilmaz T, Zachrisson BU, Maino BG. Am J
Orthod Dentofacial Orthop. 2008 Sep;134(3):353-60.
MGBM system: new protocol for Class II non extraction treatment without
cooperation. Maino BG, Gianelly AA, Bednar J, Mura P, Maino G. Prog Orthod.
2007;8(1):130-43
References suggest by Donald Nelson.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
Papadopoulos, M.A. and F. Tarawneh, The use of miniscrew implants for temporary
skeletal anchorage in orthodontics: a comprehensive review. Oral Surg Oral Med
Oral Pathol Oral Radiol Endod, 2007. 103(5): p. e6-15.
Papadopoulos, M.A., Orthodontic treatment of Class II malocclusion with miniscrew
implants. Am J Orthod Dentofacial Orthop, 2008. 134(5): p. 604 e1-16; discussion
604-5.
Li, F., et al., Comparison of anchorage capacity between implant and headgear
during anterior segment retraction. Angle Orthod, 2011. 81(5): p. 915-22.
Heymann, G.C., et al., Three-dimensional analysis of maxillary protraction with
intermaxillary elastics to miniplates. Am J Orthod Dentofacial Orthop, 2010. 137(2):
p. 274-84.
Graham, J.W., Profound, needle-free anesthesia in orthodontics. J Clin Orthod, 2006.
40(12): p. 723-4.
Elias, C.N., A.C. de Oliveira Ruellas, and D.J. Fernandes, Orthodontic implants:
concepts for the orthodontic practitioner. Int J Dent, 2012. 2012: p. 549761.
Kravitz, N.D. and B. Kusnoto, Risks and complications of orthodontic miniscrews.
Am J Orthod Dentofacial Orthop, 2007. 131(4 Suppl): p. S43-51.
Cornelis, M.A., et al., Modified miniplates for temporary skeletal anchorage in
orthodontics: placement and removal surgeries. J Oral Maxillofac Surg, 2008. 66(7):
p. 1439-45.
Keim, R.G., Who places miniscrews? J Clin Orthod, 2008. 42(9): p. 489-90.
Orthodontists, A.A.o., Informed Consent for the Orthodontic Patient - Risks and
Limitations of Orthodontic Treatment, 2005: St. Louis, MO.
Policy, O.P.L.I., American Association of Orthodontists Insurance Company, 2008:
Montpelier, VT. p. 1-16.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
Baxmann, M., et al., Expectations, acceptance, and preferences regarding
microimplant treatment in orthodontic patients: A randomized controlled trial. Am J
Orthod Dentofacial Orthop, 2010. 138(3): p. 250 e1-250 e10; discussion 250-1.
Cheng, S.J., et al., A prospective study of the risk factors associated with failure of
mini-implants used for orthodontic anchorage. Int J Oral Maxillofac Implants, 2004.
19(1): p. 100-6.
Melsen, B., et al., Factors contributing to the success or failure of skeletal anchorage
devices: an informal JCO survey. J Clin Orthod, 2010. 44(12): p. 714-8; quiz 743.
Papageorgiou, S.N., I.P. Zogakis, and M.A. Papadopoulos, Failure rates and
associated risk factors of orthodontic miniscrew implants: a meta-analysis. Am J
Orthod Dentofacial Orthop, 2012. 142(5): p. 577-595 e7.
Santiago, R.C., et al., Correlation between miniscrew stability and bone mineral
density in orthodontic patients. Am J Orthod Dentofacial Orthop, 2009. 136(2): p.
243-50.
Crismani, A.G., et al., Miniscrews in orthodontic treatment: review and analysis of
published clinical trials. Am J Orthod Dentofacial Orthop, 2010. 137(1): p. 108-13.
Poggio, P.M., et al., "Safe zones": a guide for miniscrew positioning in the maxillary
and mandibular arch. Angle Orthod, 2006. 76(2): p. 191-7.
Qiu, L., et al., Accuracy of orthodontic miniscrew implantation guided by
stereolithographic surgical stent based on cone-beam CT-derived 3D images. Angle
Orthod, 2012. 82(2): p. 284-93.
Chen, Y.J., et al., A retrospective analysis of the failure rate of three different
orthodontic skeletal anchorage systems. Clin Oral Implants Res, 2007. 18(6): p. 76875.
Miles, R., Contemporary Class II orthodontic and orthopaedic treatment. Aust Dent J,
2008. 53(2): p. 193; author reply 193.
Solano-Mendoza, B., et al., Maxillary protraction at early ages. The revolution of new
bone anchorage appliances. J Clin Pediatr Dent, 2012. 37(2): p. 219-29.