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Objective:To investigate the role played by the cranial base flexure in influencing the sagittal and vertical position of the jaws in Indian population.Materials and Methods:Lateral cephalograms of 108 subjects were divided into three categories (Group A: NSAr > 125°, Group B: NSAr-120°-125°, Group C: NSAr < 120°) according to value of NSAr. Measurement of eight angular (SNA, SNB, NPg-FH, ANB, NAPg, SN-GoGn, Y-Axis, ArGo-SN) and seven linear (N-S, S-Ar, Ar-N, Ar–Pt A, Ar–Gn, Wits appraisal, N- Pt A) variables were taken.Results:Pearson correlation coefficient test was used to individually correlate angular and linear variables with NSAr for the whole sample as well as in individual group. Unpaired t-test was used to analyze the difference in the means of all the variables between the three groups. Significance was determined only when the confidence level was P < 0.05. Several parameters (SNB, NAPg, ANB, Y-Axis, GoGn-SN) showed significant positive correlation while others showed negative correlation (SNA, NPg-FH, N-S) with NSAr.Conclusions:This study show cranial base angle has a determinant role in influencing the mandibular position and it also affects both the mandibular plane angle and y-axis. Flattening of the cranial base angle caused a clockwise rotation of the mandible. The jaw relation tends to change from class III to class II, with progressive flattening of the cranial base and vice-versa.

Aim:To analyze and determine maxillary and mandibular arch form of Gujarati (Indian) adults with normal occlusions. Materials and methods:Fifty seven study models of untreated individuals were examined. Six measurements of both the arches were taken, and five independent ratios were determined. Character and shape of both the arches were studied and compared using various statistical analyses for males and females between both the arches. Results:As moving from anterior to posterior, both the arches diverge proportionally, except in second molar area where slight convergence toward midline was noted. Females had proportionally narrower arch dimensions than those for males. Five arch forms were determined according to relative deviations of various ratio combinations, and all subjects were classified for mandibular arch form by nonhierarchical stepwise method.