Assessment of accuracy and reliability of Pont's index in different classes of dental malocclusion
Introduction: Proper interdigitated dentition, ideal arch form and widths are the key for occlusion, function and stability. Different indices are used by the clinicians to assess the amount of expansion required to obtain ideal arch width and to relieve crowding. Pont’s Index introduced by Pont, can be easily applied and it could provide the valuable information to help treatment planning. The rationale of this study was to assess the accuracy and reliability of Pont's index in calculating the dental arch width in different classes of dental malocclusions.
Material and methods: A total of 50 scanned models of patients were included in the study. The digital measurements were taken from scanned models via CS Model+ software and manual measurements were taken using digital vernier caliper from the same dental casts. Mesiodistal widths of maxillary incisors, Inter-premolar widths (IPW) and Intermolar widths (IMW) were measured both digitally and manually. Predicted arch widths were calculated using Pont’s prediction formula.
Results: Statistically significant differences between actual and predicted values for IPW and IMW were found. Excellent correlation was observed between all digital and manual measurements. Maxillary central incisors, IPW and IMW were larger in males compared to females for both digital and manual measurements. IPW was significantly greater in class-III than in other classes of dental malocclusions.
Conclusions: Pont’s index is not a reliable method for predicting dental arch width in orthodontic patients. Maxillary central incisors, IPW and IMW were larger in males compared to females for both digital and manual measurements. IPW was significantly greater in class-III than in class I and II.