Class III
Historically –mandibular
overdevelopment
Combination
Recently Maxillary
Retrusion (60%)
Ant./Post. Crossbite
Ellis E, McNamara JA. Components of adult Class III malocclusion. J Oral Maxillofac Surg 1984.Guyer EC, Ellis EE, McNamara JA, Behrents RG. Components of Class III malocclusions in juveniles and adolescents.
Angle Orthod 1986.
ETIOLOGY OF CLASS III
MALOCCLUSION
3.5% US
14% Chinese
and Japanese
INCIDENCE
3.4% Indian
Ast DB, Carlos JP, Cons NC. The prevalence and characteristics of malocclusion among senior highschool students inupstate New York. Am J Orthod 1965.
Irie M, Nakamura S. Orthopedic approach to severe skeletal Class III malocclusion. Am J Orthod 1975.Kharbanda OP, Siddhu SS, Sundarum KR, Shukla DK. Prevalence of malocclusion and its trait in Delhi children. J Indian
Orthod. Soc 1995.
INCIDENCE
Orthodontic Camouflage
Orthognathic surgery
Distraction osteogenesis
Growth Modification
Tindlund RS. Orthopaedic protraction of the midface in the deciduous dentition. J Craniomaxillofac Surg 1989.
TREATMENT OPTIONS
Current Txprotocol for orthopedic Maxillary
Protraction is by means of elastic
Facemask
Chin Cup
Expansion
Turley, P.K.: Orthopedic correction of Class III malocclusion with palatal expansion and custom protraction
headgear, J. Clin. Orthod. 1988.
Hideo, M.: Early application of chincup therapy to skeletal Class III malocclusion, Am. J. Orthod. 2002.
Sakamoto M, Sugawara J, Umemori M, et al. Craniofacial growth of mandibular prognathism during pubertalgrowth period in Japanese boys – Longitudinal study rom 10 to 15 years of age. J Jpn Orthod Soc 1996
Physical appearance of the extra-
oral appliance
Skin irritation from the
anchorage pad
POOR COMPLIANCE
of child to wear it, major problem associated with
facemask therapy
Sung, S.J. and Baik, H.S.: Assessment of skeletal and dental changes by maxillary protraction, Am. J. Orthod. 1998.
PROBLEMS IN CONVENTIONAL THERAPY
NEED OF NEW APPLIANCE
Hence there was a need of another appliance to enhancethe patient compliance with much better biomechanics
Present paper discussed the construction and clinicalprocedure of an intraoral fixed appliance for thetreatment of Class III malocclusion in young patientswithout relying on patient co-operation
Fixed Maxillary Appliance with soldered buccal arm on first molar band for Class Traction
Fixed Mandibular Appliance with welded buccal tube on first molar band to headgear facebow
A 0.045 inch headgear face bow with the outer bows bent out for Class III elastic attachment with a soldered stop at terminal end on inner bow
Components of Modified Fixed Nanobite Tandem Appliance (MFNTA)
FIXED MAXILLARY APPLIANCE
Sean Shih-Yao Liu, Hee-Moon Kyung and Peter H. Buschang.
Continuous forces are more effective than intermittent forces in
expanding sutures. Eur J Orthod 2010.
FIXED MANDIBULAR APPLIANCE
Veerendra Prasad, Vijay P. Sharma, PradeepTandon, Gyan P. Singh. A new fixed biteplane. J of Clinical Orthod 2008.
Modified Fixed Nanobite Tandem
Appliance (MFNTA)
Mechanism of action of MFNTA
Schematic representation of a line offorce through the center of resistance(CR) of maxilla, which will result in atranslatory movement of maxilla. Inthe long vertical dimension of Class IIIpatients, it is advisable to adjust theline of force ≤20° to the occlusalplane (OP) to prevent downwardrotation of mandible.
Mechanism of action of MFNTA
Schematic representation of a line offorce for Class III with flat mandibularplane; it is advisable to adjust the lineof force ≥25° to the occlusal plane(OP) which will result in downwardand forward movement (clockwise) ofmidface and dentition resulting indownward and backward rotation ofmandible.
A CLINICAL REPORT OF PEDIATRIC PATIENT WITH CLASS III MALOCCLUSION TREATED BY MFNTA
Pretreatment patient photographs
She and herparents werepsychologicallydepressed withher facialappearance andreverse bite
Patient photographs with appliance
Post treatment Patient photographs
Posttreatmentfacial photographsof the patientshowed markedimprovement infacial esthetics andcorrection of reversebite
Pre and post treatment study model
GTRV= 0.60(If GTRV is between .33 to .88 then Class III malocclusion can be treated nonsurgical)
Early Timely Treatment of Class III Malocclusion: Semin Orthod 11:140–145 © 2005 Elsevier Inc.
CONCLUSION
Pre and post treatment record revealed-
significant skeletal improvement,
and marked improvement in facial balance
Address for correspondence
Dr. Prabhat K C,
Assistant Professor, Department of Orthodontics,
Dr. Z A Dental College, Aligarh Muslim University,
Aligarh, India -202001.Email ID-
[email protected] Modified Fixed
Nanobite Tandem Appliance (MFNTA)