Abstract:

 Objective To study the relationship between the mesiodistal tipping degree of maxillary and mandible posterior teeth and different vertical facial skeletal types of subjects with normal occlusion. Methods 163 subjects with normal occlusion were selected, lateral cephalograms were taken and divided into three different facial skeletal types. The difference of the mesiodistal tipping degrees and intersection angles of upper and lower posterior teeth between the three different facial skeletal types were analyzed. Results Among 163 subjects, vertical growth pattern, average growth pattern and horizontal growth pattern were 24, 96 and 43 respectively. There were statistic differences of mesiodistal tipping degrees of the first and second maxillary and mandible premolar and the first permanent molar between vertical growth and horizontal growth pattern, horizontal growth and average growth pattern（P <0.05）. But there were no statistically significant differences between vertical growth and average growth pattern （P>0.05）. The differences of the maxillary and mandible posterior teeth′s intersection angle among three vertical facial skeletal types had no statistic significance（P >0.05）. Conclusion Different vertical facial skeletal type has its own normal and coordinated posterior teeth mesiodistal tipping degrees.

Key words: normal occlusion, facial growth pattern, posterior tooth long axile, tipping degree