Role of cranial base flexure on dento skeletal changes following to functional appliance therapy

The role of cranial base flexure in determining the position of the glenoid fossa and expressing the anteroposterior position of the mandible has been under investigation for years. It is said that large Saddle angle can result in class II malocclusion conversely small Saddle angle can cause anterior location of the fossa and resulting in class III malocclusion. According to this theory some investigators believe that class II malocclusion caused by large Saddle angle is difficult to influence with functional appliance therapy. The present study was aimed at evaluating the role of Saddle angle on dentoskeletal changes following the use of Two Piece Function Corrector)TPFC (functional appliance. Methods & Materials: Two groups of untreated skeletal Class II, Div 1 malocclusion were selected on the basis of Saddle angle degree. The first group) n=25 (consisted of 13 boys and 12 girls with Saddle angle less than 122ْ and the second group) n=25(included 8 boys and 17 girls with Saddle angle larger than 126ْ. SNA, SNB, ANB, SN-Pog, Total Mandibular Length, Wit’s, GoMe-SN, Body Mandibular Body Length, Ramus Height, N┴FH to A-N┴FH to Pog, IMPA, Overjet were measured before and after treatment by lateral cephalograms to evaluate dentoskeletal changes. Paired t-test was used to compare the differences between two groups and effect of TPFC on dento skeletal structures. The two groups showed noticable improvement in dento skeletal relationship. This study indicated no statistically significant differences between two groups. The amount of Saddle angle has no effects on treatment results with functional appliance therapy.