RESUMO
Introduction: Boston University (BU) approach is a method for early prediction of unerupted permanent mandibular teeth widths based on the mesiodistal widths (MDWs) of primary mandibular canines and first molars. The present study was conducted to test the validity of BU approach by comparing it with Tanaka–Johnston (T/J) approach in the contemporary population. Aims and Objective: The aim of the study was to determine the applicability of BU approach for prediction of the MDWs of canines and premolars in the primary schoolchildren of rural Bengaluru. Materials and Methods: The study was conducted in 100 healthy schoolchildren of rural Bengaluru aged between 7 and 11 years. The MDWs of canines and premolars were predicted using both T/J and the considered BU approaches for all the children and were compared. Results: The correlation coefficient showed a statistically significant correlation between the predicted tooth size from the two predicted methods in the upper and lower arches (P < 0.001), with Pearson's correlation coefficient showing the very strong positive relationship (r = 0.7). Significant differences were seen between the mean predicted width of canines and premolars by both the approaches (P < 0.001). Conclusion: In spite of the limitations, we recommend the use of BU approach to predict arch length-tooth material discrepancy at an early age and to get at least an approximate estimation of the required space. We also advocate the necessity of further research on this approach prospectively.
RESUMO
Introduction: Boston University (BU) approach is a method for early prediction of unerupted permanent mandibular teeth widths based on the mesiodistal widths (MDWs) of primary mandibular canines and first molars. The present study was conducted to test the validity of BU approach by comparing it with Tanaka–Johnston (T/J) approach in the contemporary population. Aims and Objective: The aim of the study was to determine the applicability of BU approach for prediction of the MDWs of canines and premolars in the primary schoolchildren of rural Bengaluru. Materials and Methods: The study was conducted in 100 healthy schoolchildren of rural Bengaluru aged between 7 and 11 years. The MDWs of canines and premolars were predicted using both T/J and the considered BU approaches for all the children and were compared. Results: The correlation coefficient showed a statistically significant correlation between the predicted tooth size from the two predicted methods in the upper and lower arches (P < 0.001), with Pearson's correlation coefficient showing the very strong positive relationship (r = 0.7). Significant differences were seen between the mean predicted width of canines and premolars by both the approaches (P < 0.001). Conclusion: In spite of the limitations, we recommend the use of BU approach to predict arch length-tooth material discrepancy at an early age and to get at least an approximate estimation of the required space. We also advocate the necessity of further research on this approach prospectively.
RESUMO
Bolton’s ratio is an indispensable parameter used in orthodontic diagnosis to evaluate the tooth size discrepancy. However, these norms have been established for Caucasian population and population variations necessitate the evaluation of these ratios for Vidarbha population. The objectives of the present study were to determine Bolton’s ratio for Vidarbha population, compare them with original Bolton’s ratios and determine the clinical significance of these differences.METHODSThe study sample consisted of study casts of 300 subjects in the age range of 18-30 years, all belonging to Vidarbha population, having a full complement of teeth. Tooth dimensions were measured using digital vernier caliper and Bolton’s overall ratio and anterior were calculated. The data calculated was statistically analysed for range, mean, standard deviation and coefficient of variation. Unpaired t-test was applied to draw a difference between the results of this study and the results from Bolton’s study.RESULTSBolton’s overall and anterior ratio norms for Vidarbha population sample were found to be 88.15 and 78.50, respectively, with standard deviation of 3.27 and 3.19, respectively. The range of overall ratio noted was 80.36–98.44, and the range of anterior ratio was 67.74–89.70.CONCLUSIONSIn general, the values obtained from this study for the Vidarbha population differ from the data of Caucasian population. So, it can be inferred that the established Bolton’s values for Caucasians cannot be used for the Vidarbha population. Hence, population specific standards are necessary for clinical assessment.