Bilateral maxillary canine-first premolar tansposition in permanent dentition

Transposition is a dental anomaly characterized by the exchange of position between two adjacent teeth, especially in relation to their roots, or development and eruption of a tooth in a position normally occupied by a nonadjacent tooth. Transposition of the maxillary canine and first premolar has a low prevalence in the population and it primarily affects maxillary canines and premolars. The aetiology of the transposition remains unclear, although it has been associated with genetic factors. It may also be related to a combination of localised factors such as malformation of adjacent teeth, tooth agenesis, retention of the deciduous canine and a history of local trauma. If uncorrected, the results are often both functionally and esthetically unsatisfactory. This case report presents treatment of a female patient with complete bilateral transposition of maxillary canine and premolar. The patient was treated orthodontically with non-extraction fixed mechanotherapy by simulation of maxillary first premolar as canine bilaterally

Comparison of three mixed dentition analysis methods in orthodontic patients at AKUH

To compare the actual sum of canine and premolars and that predicted from three mixed dentition prediction methods in orthodontic patients at the Aga Khan University Hospital [AKUH], Karachi. Cross-sectional comparative study. Orthodontic clinic at the Aga Khan University Hospital from June 2002 to December 2007. Data were collected using pretreatment records including orthodontic files and plaster casts of 121 orthodontic patients. Digital caliper was used to measure the mesiodistal widths of permanent teeth from 1st molar to 1st molar in mandibular arch, and central incisors and 1st molars in maxillary arch. The methods of Tanaka and Johnston, Moyers, and Bernabe and Flores-Mir were used to predict the mesiodistal widths of the canine and premolars. Comparison between the actual and predicted sum of the mesiodistal widths of canine and premolars was made for each prediction method, using paired sample t-test. There were 45 males and 76 females with average ages of 13.3 +/- 1.3 and 13.4 +/- 0.8 years respectively. For males statistically significant differences were found for Moyers at the 75th percentile and Bernabe and Flores-Mir method whereas for females only the Bernabe and Flores-Mir's method showed significant results. However, no significant difference was found in both genders for Tanaka and Johnston method. In the studied orthodontic patients for males Moyers 50th percentile and Tanaka and Johnston methods could be used; while for females Moyers 75th percentile and Tanaka and Johnston methods were applicable for mixed dentition analysis