A Rational Factor for Overjet in Class II Division 1 Malocclusion – Growth Pattern or Bolton’s Discrepancy” Dr.Amit

Abstract: Introduction: The increased overjet in Class II Division 1 malocclusion subjects may be due to hyperdivergent growth pattern or Bolton’s tooth size discrepancy. The aim of this investigation was to find the rational factor for overjet in Class II Division 1 malocclusion as growth pattern or Bolton's discrepancy in these subjects. Methods: 120 untreated Class II Division 1 cases who reported to the department for orthodontic treatment were included in this study. The lateral cephalometric radiographs were evaluated for growth pattern and grouped into vertical and horizontal growers. The Bolton's ratio and overjet was measured from the study models obtained. Results: A statistically significant linear positive correlation was seen between overjet with mandibular plane angle and negative with Jarabak’s ratio. However, a weak correlation between overjet and Bolton's discrepancy was present in the overall sample. When the vertical growth pattern subjects were analyzed separately, statistically significant moderate correlation (r = 0.462) was present between overjet and mandibular growth pattern. Conclusion: Clinician should take a note during diagnosis of subjects of Class II Division 1 with increased overjet regarding the vertical control during treatment. In such cases extrusive mechanics should not be used to avoid increasing the mandibular plane angle and thereby worsening vertical relation.