Analysis of cephalometrics for orthognathic surgery: Determination of norms applicable to Rajasthani population

Natl J Maxillofac Surg. 2010 Jul;1(2):102-7. doi: 10.4103/0975-5950.79209.

Abstract

Aims: To determine the hard tissue surgical cephalometric norms statistically and geometrically in well-balanced faces having clinically acceptable facial profile in the Rajasthan population. To compare the cephalometric analyses of Rajasthanis males and females and to compare the craniofacial pattern of Rajasthani population with Caucasian norms.

Materials and methods: Lateral cephalograms of 200 subjects (100 males and 100 females) in the age group of 18-25 years, class I malocclusion and acceptable facial profile were obtained. Cephalometric analysis was performed and studied.

Results: The study revealed that parameters, such as all horizontal skeletal parameters, PNS-N, PNS-ANS, Ar-Go, Go-Pg and upper OP to HP angle show no statistical significant difference between Rajasthani males and females. When comparing Rajasthani males and Caucasian males, the study suggested statistically significant difference in the mean values of parameters, such as PTM-N, L1-MP, 6-MP, Go-Pog, B-Pog, Ar-Go-Gn, U1 to NF and L1 to MP. When comparing Rajasthani females and Caucasian females, the study revealed no statistically significant difference between the mean values of parameters, such as N-A-Pg, N-A, N-B, L1-MP, Ar-Go-Gn, upper OP to HP angle and AB-OP and rest of the parameters showed highly significant difference between Caucasian females and Rajasthani females.

Conclusion: This study indicates that Rajasthani population has a bimaxillary protrusion with predominant tendency toward horizontal growth pattern of the mandible and this tendency is further exaggerated in females. Rajasthani females also showed an increased length of the anterior cranial base, maxilla and mandible and in dental parameters they showed increased maxillary dental height and both Males and females showed decreased mandibular dental height.

Keywords: COGS analysis; lateral cephalograms; orthognathic surgery.