A Newly Proposed Regression Equation for Mixed Dentition Analysis Using the Sum of the Width of Permanent Mandibular Central Incisors and Permanent Mandibular First Molars as a Predictor of Width of Unerupted Canine and Premolars

Objective: To determine linear regression equation to predict the mesiodistal widths of the permanent canines and premolars based on the sum of the widths of the two permanent mandibular first molars and two mandibular central incisors. Material and Methods: The sample consisted of 800 (400 males and 400 females) permanent dentition casts of Chhattisgarh population. Mesiodistal crown widths of teeth were measured with digital caliper. The correlation and linear regression equations between the calculated four teeth (two permanent mandibular first molars and two central incisors) and the canine-premolars segments of both the arches were developed. Results: No significant differences were found in right and left side of the arch. Sexual dimorphism was significant in teeth sizes with higher mesiodistal dimension in males. A good correlation values varying from 0.51 to 0.67 was found. New standardized regression equations were formulated for the prediction of the mesiodistal widths of unerupted canines and premolars for Chhattisgarh population. Conclusion: Calculating mesiodistal widths of unerupted canine and premolars with help of two permanent mandibular molars and two mandibular central incisors, which erupt early in the oral cavity, can be an alternative and best predictor for the mixed dentition analysis.

A New Regression Equation Proposed For Mixed Dentition Analysis in Chhattisgarh, Central India Population

Objective: To develop and propose a new regression for mixed dentition analysis in Chhattisgarh, Central India population. Material and Methods: The permanent dentition dental casts of 800 (400 males and 400 females) Chhattisgarh subjects were selected. Digital caliper was used to measure the mesiodistal crown widths of teeth. The linear regression equations and correlation between four mandibular incisors and the canine-premolars segments of maxillary and mandibular arches were developed (modified Tanaka-Johnston equation) and proposed for Chhattisgarh population. Results: New standardized regression equations were formulated to predict the mesiodistal widths of unerupted canines and premolars especially for Chhattisgarh, Central India population. The equation in males for maxillary arch was Y = 11.90 + 0.39 (X) and for mandibular arch was Y = 12.23 + 0.36 (X). Similarly, the equation in females for maxillary arch was Y = 14.40 + 0.26 (X) and for mandibular arch was Y= 10.26 + 0.43 (X). A significant sexual dimorphism in teeth sizes was seen with higher mesio distal dimension in males in Chhattisgarh population. Conclusion: Sum of the mesiodistal diameter of permanent mandibular incisors can be used reliably to predict/estimate the sum of mesiodistal diameters of unerupted canines and premolars with the new regression equations.

Impaction of the maxillary central incisor associated with supernumerary tooth: Surgical and orthodontic treatment.

Impaction of maxillary permanent incisor is not a frequently case in dental practice, but its treatment is challenging because of its importance to facial esthetics. Supernumerary teeth are the main cause of impaction of upper incisor. Supernumerary teeth when present can cause both esthetic and pathologic problems. Supernumerary teeth in the maxillary midline are common. Early detection of such teeth is most important if complications are to be avoided. We report a case of 12 year old male with an impacted supernumerary tooth in the maxillary anterior region, which was interfering with the eruption of the permanent, left central incisor. The impacted supernumerary tooth was surgically removed. With the application of an orthodontic traction, impacted left maxillary central incisor was brought down to its proper position in the dental arch.