RESUMO
The aim of this study was to examine the applicability of simple equations proposed by Melgaco to predict the mesiodistal widths of the unerupted mandibular permanent canines and premolars in patients visiting Islamic International Dental hospital, Islamabad. This study was conducted during 2007-2008 at orthodontic department of Islamic International Dental Hospital, Islamabad. The sample consisted of 200 dental casts [100 male 100 female], obtained from patients reporting at the department of orthodontic, Islamic International Dental Hospital Islamabad, with the age range between 13 to 21 years. Mesiodistal tooth widths were measured with a digital vernier caliper. Correlation and determination coefficients were found between Sum of mandibular Incisors and first Molars [SMI] and Sum of actual width of mandibular Canine and Premolars [SCPM] of mandibular arch. A paired Student t test was used to compare the predicted and actual sum of the mandibular permanent Canines and Premolars [SCPM] for both genders combined and separately. Correlation coefficient was 0.673 and determination coefficient was 0.452 between SMI and actual SCPM. Significant difference was found between predicted and actual values of SCPM for male [0009] and for both genders combined [0.000]. Female subjects showed no significant difference [0.010].Only the simple equation proposed for female subjects by Melgaco et al is applicable in our sample