Validity of Visual Vector Relationship for the Clinical Assessment of Anterior Malar Projection and the Changes Observed in Facemask Therapy Patients” – A Retrospective Stud

Abstract

Aims: The present study was undertaken to evaluate whether a visual classification of anterior malar support using vector relationship is supported by cephalometric analysis and to assess the effects of face mask therapy on vector relationship and other cephalometric variables. Methods and Material: Pre-treatment profile photographs and lateral cephalograms of forty adult subjects (20 positive vector and 20 negative vector) were collected. Pre-treatment and post-treatment profile photographs and lateral cephalograms of 20 patients successfully treated by facemask therapy were collected. Traditional cephalometric measurements were used to describe changes between pretreatment, posttreatment lateral cephalograms and profile photographs. Statistical analysis used: Student’s unpaired t test were used to compare the differences between SNO measurements for group A and group B and paired t-test was done to compare the pre-treatment and posttreatment lateral cephalograms. Results: Between the positive and negative group, an analysis for sexual dimorphism showed no statistically significant difference. Differences in skeletal support between the negative and positive vector groups assessed using SNO angles(4.6 0 ) were highly significant. SNO angulations in the negative vector group were smaller than the positive vector controls by an average of 4.6 0 . Conclusions: The null hypothesis of the study that there is no significant difference between face mask therapies on visual vector relationship is rejected because though face mask protraction therapy did not make a negative vector patient to positive vector, there was significant improvement in the malar projection. Key-words: Visual vector relationship, anterior malar projection, facemask, retrospective.