Preliminary Study On The Correlation Among Different Vertical Skeletal Types Of Adult Female Occlusal Plane Inclination And Facial Soft Tissue Profile At The Lower Anterior Face

Objective: To study the correlation above occlusal plane inclination and facial soft tissue profile at the lower anterior face in adult female with skeletal class Ⅱ malocclusion,and to provide a preliminary theoretical basis for the relationship between two index.Methods: 90 skeletal class Ⅱ malocclusion adult female patients,aged 18 to 28 years old,were divided into three groups based on Go Gn-SN angle:low angle group(Go Gn-SN<27.2,n=30),normal angle group(27.2°≤Go Gn-SN≤37.7°,n=30)and high angle group(Go Gn-SN>37.7°,n=30).The soft tissues and dentoskeletal landmarks and subsequent measurements were performed and analyzed using SKETCHPAD 5.06 and SPSS23.0software,respectively.Results:(1)Adult women had significant differences in anterior,posterior and maxillary occlusal plane inclination angle(AOP-FH,POP-FH and COP-FH),but not in OP-AB angle.(2)Among the soft tissue profile indicators,sulcus angle of mentolabial,Merrifield’s Z angle and inclination of mental sulcus had significantly difference among the three groups.The distance of labial inferius to E line and the distance of superior labial sulcus to E line was statistically significant between the high and low angle groups respectively.The distance of mentolabial sulcus to E line,the position relationship between upper lip and chin and the position relationship between lower lip and chin were significantly different between the normal and high angle group and the normal and lower angle groups.(3)Correlation study results show that AOP-FH and the distance of labial inferius to E line,POP-FH and the distance of superior labial sulcus to E line,the distance of mentolabial sulcus to E line,Merrifield’s Z angle,sulcus angle of mentolabia,the position relationship between upper lip and chin,the position relationship between lower lip and chin,inclination of mental sulcus,and COP-FH and the distance of labial inferius to E line,the distance of mentolabial sulcus to E line,Merrifield’s Z angle,sulcus angle of mentolabial,the position relationship between lower lip and chin,All of these had significant correlations.Conclusion: The occlusal plane inclination affects the facial soft tissue profile with different vertical skeletal types in adult female with skeletal class Ⅱ malocclusion lateral appearance of the soft tissue,when diagnose inter relationship,the combination of COP-FH and POP-FH consideration may give a more comprehensive diagnostic result.