Correlation of Vertical Dentoalveolar Heights with Palatal Plane Inclination in Adults with Different Vertical Facial Patterns

Introduction: Various studies showed inconsistent and different results regarding the correlation between open bites and palate planes whether normal or abnormal. This study had for objective to investigate the correlation between dentoalveolar heights and palatal plane inclination in different vertical facial patterns.

Materials and methods: 120 lateral cephalometric radiographs (60 females and 60 males) were selected from the archives of the Faculty of Dentistry, Beirut Arab University. The sample consisted of three equal groups: hypodivergent (SN/MP<27°), normodivergent (SN/MP=27°-37°) and hyperdivergent (SN/MP>37°). The radiographs were digitally traced and cephalometric skeletal and dentoalveolar variables were measured. Statistical analysis was carried out with significance level at p<0.05.

Results: The palatal plane inclination showed statistically significant difference between hyperdivergent and both hypodivergent and normodivergent subjects with no statistically significant difference between hypodivergent and normodivergent subjects. A statistically significant difference in the upper anterior dentoalveolar height (UADAH) was found between hypodivergent and both hyperdivergent and normodivergent subjects. No statistically significant difference was found in the other dentoalveolar heights between the different vertical patterns. A negative moderate correlation was only observed between the palatal plane angle and UADAH in the hyperdivergent group. Multiregression analysis showed that the greatest contribution to overbite pooled across all groups other than the skeletal pattern was attributed to UADAH.

Conclusion: UADAH seems to influence the overbite depth compared to other dentoalveolar heights. It is possible that UADAH acts as a compensatory factor for palatal plane inclination in hyperdivergent subjects.