Vertical, Sagittal and Transverse Effects of Semi Rapid Maxillary Expansion Protocol Using a Removable Expansion Appliance: A Cephalometric and Model Based Study

• Author Details:   
• Alka M. Banker ^*
• Dhaval Somani
• Bhagyashree Desai
• Rahul P. Muchhadia

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Introduction: The aim of this study was to evaluate the vertical, sagittal and transverse effects of semi rapid maxillary expansion (SRME) in patients with transverse maxillary discrepancies using a modified removable expansion appliance assessed by lateral cephalograms and dental models.
Materials and Methods: The lateral cephalograms and dental models of 50 treated patients group were compared with those of 29 untreated control group at 3 different times: pretreatment (T0), after expansion (T1) and after fixed appliance therapy (T2). The mean age for treated group was 13.8yrs (32 females; 18 males) and control group was 13.2yrs (15 males; 14 females). A total of 18 measurements (8 angular; 10 linear) were measured in vertical, sagittal and transverse planes at T0, T1 and T2 stages. The T0-T1, T1-T2 and T0-T2 changes were compared statistically in treated group with respect to the corresponding untreated control group. The intra-group and inter-group comparisons were statistically analyzed using Wilcoxon signed rank test.
Results: In comparison to controlled group the following parameters in treated group showed a statistically significant change from T0 to T2. In vertical plane increase in ANS–Me and in sagittal plane decrease in angle ANB and OJ; increase in SNB and U1-SN was seen. In the transverse plane ICW, IPW, IMW, PMW showed net gain of 3.27, 5.06, 3.7 and 2.82mm respectively.
Conclusion: The results of present study suggest that the design and protocol followed in using SRME is effective for the correction of maxillary transverse discrepancies with acceptable vertical and sagittal control.

Keywords: Semi Rapid Maxillary Expansion, Transverse Maxillary Deficiency, Sagittal and Vertical Effect, Lateral Cephalogram, Model study.