Transverse changes in lateral and medial aspects of palatal rugae after mid palatal expansion: A pilot study

INTRODUCTION: Palatal rugae has established role in forensic identification of an individual due to its stability in growth as well as orthodontic treatment. However effect of orthodontic mid-palatal expansion on rugae stability still requires further investigation. Hence, this study was aimed at evaluating the stability of palatal rugae in transverse dimension in adolescent patients of mid-palatal expansion. MATERIALS AND METHODS: The study sample consists of 14 subjects (10F,4M, age 12.4 ± 2.0 years) with transverse maxillary constriction, treated with bonded and banded rapid maxillary expansion (RME) appliance. 1(st) to 3(rd) rugae on pre- and post-expansion casts were recorded synchronously. Inter-medial and inter-lateral rugae distance were measured with digital calipers to record the transverse positional rugae changes. RESULTS: There was a statistically significant (p < 0.05) increase in values after expansion between medial aspects of 2(nd) (p = 0.002) and 3(rd) rugae (p = 0.005) and lateral aspects of 1(st) (p = 0.015), 2(nd) (p = 0.006) and 3(rd) (p = 0.001) rugae. The transverse changes were recorded in the order of 3(rd) rugae >2(nd) rugae >1(st) rugae. CONCLUSION: This pilot study does not support stability of medial and lateral ruga points of 2(nd) and 3(rd) primary rugae for forensic identification in individuals treated with mid palatal expansion.