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RAJIV GANDHI UNIVERSITY OF HEALTH SCIENCES, BANGALORE,
KARNATAKA
ANNEXURE – II
PROFORMA FOR THE REGISTRATION OF SUBJECTS FOR DISSERTATION
1.
Name of the candidate
and address (in block letters)
DR.SRIJAN SHILPI
C-26/77 , URJANAGAR, MAHAGAMA, GODDA
JHARKHAND.
2.
Name of the Institution
M. S. RAMAIAH DENTAL COLLEGE &
HOSPITAL, BANGALORE.
3.
Course of Study and Subject
MASTER OF DENTAL SURGERY IN
DEPARTMENT OF ORTHODONTICS AND
DENTOFACIAL ORTHOPEDICS.
4.
Date of Admission to Course
26/07/2013
5.
Title of the topic
RELATIONSHIP OF THE FUNCTIONAL
OROPHARYNX TO CRANIOFACIAL
MORPHOLOGY IN SKELETAL CLASS II
PATIENTS- A CEPHALOMETRIC STUDY.
6.
Brief resume of the intended work:
6.1 Need for the study.
Normal airway is one of the important factor for the normal growth of craniofacial structure.The
pharynx is a tube shaped structure which is divided into 3 parts – nasopharynx, oropharynx and
laryngopharynx.6
The oropharyngeal airway is bound by the glotic aperture below and leads into the
nasopharyngeal airway above. This portion of the upper airway has attracted less attention than
its nasal counterpart. There are significant relationships between the pharyngeal dimension and
craniofacial abnormalities such as ,mandibular deficiency, bimaxillary retrusion , steep occlusal
plane , increased mandibular plane angle, and the more caudally positioned hyoid bone results
in narrowing of the pharyngeal airway passage.6
The purpose of this study was to make a fair representation of oropharyngeal airway by
measuring the linear distance between back of tongue and posterior pharyngeal wall in skeletal
class II cases and then correlating with certain conventional angles in order to assess its
relationship to the craniofacial morphology.
6.2
Review of literature:
A study1conducted in 1998 to find the existence of relationship between functional –
orthopedic treatment and increase in oropharyngeal airway dimensions in skeletal class II
patients and concluded that the existence of relationship between functional- orthopedic
treatment and increase in oropharyngeal airway dimension in certain skeletal class II
growing subjects.
A study2 conducted in 1999 to find a relationship between functional oropharyngeal airway
and craniofacial morphology and concluded that there was a positive co-relation between
length of mandible, the distance between third cervical vertebrae and the hyoid bone, and
the cranial base.
A study3 was conducted in 2002 to determine the changes that occurred in airway and
surrounding structures when subjects with sleep disorder breathing moved from upright to
supine position and concluded that there was no difference between the non apnoeic snorers
and the obstructive sleep apnoeic subjects in any of the postural changes recorded.
A study4 conducted in 2012 to test the hypothesis that the sagittal position of the anterior
teeth has no effect on pharyngeal airway dimension or hyoid bone position and to
investigate the influence of orthodontic retraction of the anterior teeth on each section of
pharynx and hyoid position and concluded that the pharyngeal airway size became narrower
after the treatment. Extraction of all four 1st premolars with retraction of incisors did affect
velvopharyngeal, glossopharyngeal, hypopharyngeal and hyoid position in bimaxillary adult
protrusive position.
In another study5 conducted in 2012 to compare the oropharyngeal space in sideview
radiographs of children with atypical deglutition and normal deglutition. The results of the
study concluded that the oropharyngeal space is reduced in the group with atypical
deglutition.
In another study6 conducted in 2012 to test the hypothesis that there is no association
between saggital maxillomandibular relationship and pharyngeal airway. The results of the
study concluded that there is significant reduction in the upper airway at the level of
nasopharynx and oropharynx and airway showed a tendency to decrease from class III to
class I and class I to class II.
6.3 Aims and Objectives of the study :
1. To correlate functional oropharynx with craniofacial morphology in skeletal class II
patients.
2. To interpret if there is any variation between different sex.
3. To determine whether there is any correlation of angular and linear measurements
with functional oropharynx.
4. To assess the average width of functional oropharynx in skeletal class II patients
belonging to the age group of 10-13 years.
7.
Materials and methods:
7.1 Source of data:A total of 100 lateral cephalograms of patients having skeletal class II
malocclusion, belonging to the age group of 10-13 years of age, present in the records of
department of orthodontics and dentofacial orthopedics, M. S. Ramaiah dental college,
Bangalore will be examined in this study.
7.2 Method of collection of data:
Methodology
The Lateral cephalograms used in the present study will be obtained from the records
present in Department of Orthodontics and Dentofacial Orthopedics, M. S. Ramaiah Dental
College Bangalore.( Using the same Cephalostat – PLANMECA 2002 cc Proline Panoramic
Unit).
Tracings will be made by the same person using a 0.3 microtip pencil on acetate paper over
an illuminated opal light box.Certain conventional anatomic landmarks will be marked and
these point will be joined to make angular and linear variables.For every subject the angular
and the linear measurements will be obtained. Later by considering these measurements we
will try to find out whether there is any relationship between functional oropharynx and
craniofacial morphology in skeletal class II patients.
I) Inclusion criteria :
1) Patients presenting with skeletal class II malocclusion in the age group of 1013 years of both the sexes.
2) Lateral cephalogram should be taken in reference to natural head position.
3) Frankfurt horizontal plane should not be in true horizontal plane and teeth in
centric occlusion.
4) C3 cervical vertebrae, hyoid bone position and oropharyngeal airway space
should be clearly identifiable.
5) ANB angle should be more than 40, along with Mcnamara readings, witts
aprasial and beta angle showing skeletal class II.
II).Exclusion Criteria:
1) Patients with craniofacial anomalies and syndromes will be excluded from the
study.
2) Patients with Frankfurt horizontal plane of more than 10 degrees above true
horizontal should not be taken.
3) Lateral cephalogram with poor resolution of reference points should not be
taken.
Statistical test:
1) The oropharyngeal airway will be correlated with the age and the
cephalometric variables using pearsons correlation coefficient test (r).
2) Student’s t- test is used to check if there is any variation between different sex.
3) The method error (ME) was determined by random selection of 1 in 10
radiographs for retracting and remeasuring them.
4) Sample size estimation – A sample size of 91 achieves 80% power to detect a
difference of -0.29000 between the null hypothesis correlation of 0.00000 and
the alternative hypothesis correlation of 0.29000 using a two-sided hypothesis
test with a significance level of 0.05000
7.3 Does the study require any investigation or intervention to be conducted on
Patients or other human or animal? If so, please describe briefly.
No. Lateral cephalograms of cases from the archieves of the departmental records will be
used for the study.
7.4 Has ethical clearance been obtained in case of above?
Not required
8. List of referances:
1.M. Murat Ozbek, UfukToygarMemikoglu, HakanGogen. Oropharyngeal airway
dimensions and functional orthopedic treatment in skeletal class II cases. Angle Orthod
1998;68(4):327-336.
2.Michael J. Trenouth, Donald J. Timms. Relationship of the functional oropharynx to
craniofacial morphology. Angle Orthod 1999;69(5):419-423.
3. Joanna M. Battagel, Amajohal, Anne-Marie smith. Postural variation in oropharyngeal
dimensions in subjects with sleep disordered breathing :Aceph study. European journal of
orthodontics 2002:24;263-276 .
4.Qingzhu Wang, PeizengJia, Nina K. Anderson. Changes of pharyngeal airway size and
hyoid bone position following orthodontic treatment of class I bimaxillary protrusion. Angle
orthod 2012;82(1):115-121.
5.Almiro Jose Machado Junior, Agricio N. Crespo. Cephalometric evaluation of the
oropharyngeal space in children with atypical deglutition. Brazilian journal of
otorhinolaryngology. 2012;78(1):120-5
6.Madhurima Nanda, Anil Singla, AnuragNegi. The association between maxillomandibular
sagittal relationship and pharyngeal airway passage dimensions. Journal of Indian
orthodontic society. 2012;46(1);48-52