Skeletal open bite cranial base characteristics in young Latin-American individuals with class I, II and III malocclusions: An observational study.

OBJECTIVE

This study aimed to compare cranial base linear and angular measurements between individuals with skeletal open bite and different sagittal skeletal relationships.

MATERIALS AND METHODS

This observational and cross-sectional study included 101 lateral radiographs of young Latin-American individuals with skeletal open bite that met the inclusion criteria and were collected from a private radiological centre. Three groups were formed. Groups 1, 2 and 3 included individuals with skeletal open bite (negative overbite and FMA>30°) and Class I (n=31), II (n=35) and III (n=35) sagittal skeletal relationship, respectively. The anterior and posterior cranial bases (SN and SBa), and cranial base angles (BaSN and ArSN) were measured. Groups were compared with one-way analysis of variance and post-hoc Scheffé tests. The influence of predictor variables on the cranial base were evaluated with linear regressions (α=0.05).

RESULTS

The cranial base angles were significantly smaller (approximately 3° to 5°) in the skeletal open bite Class III group (BaSN=127.97°± 5.86°, ArSN=120.19°±6.12°) when compared with the other groups. BaSN angle, Class I versus Class III (p<0.001) and Class II versus Class III (p<0.001). ArSN angle, Class I versus Class III (p=0.005) and Class II versus Class III (p=0.026). Multiple linear regressions showed that sex had a significant influence on both cranial base dimensions with men showing larger values than women.

CONCLUSIONS

Skeletal open bite Class III individuals show a smaller cranial base angle than Skeletal open bite Class I or II individuals.