Asrar Ahmed, Nidal Iqbal, Muhammad Zeeshan Baig, Tabeer Ayub.
Frequency of type traits of mandibular second premolars - a study.
Pak Oral Dental J Jan ;36(3):430-2.

Mandibular second premolar has two different type traits depending upon the number of cusps. In addition to this they are also identified on the basis of groove pattern unique to each type trait. The aim of this study was to determine the frequency of two variants of mandibular second premolars, unilaterally or bilaterally. This descriptive investigation was undertaken in different schools of Lahore, Pakistan. A total of 1500 children were examined for unilateral and bilateral cuspal variations, groove patterns and gender predilection. The subjects were examined in ordinary classroom chair using torch light and mouth mirror. To collect the data, the findings were recorded on a specially designed proforma. The frequency of 2 cusp type and 3 cusp type premolars was 37.5% and 62.4% respectively. U shaped and H shaped groove pattern was found to be 54% and 46% respectively. A gross difference in the frequency of 3 cusp variety was noticed. The most frequent occlusal morphological pattern was U/crescent shaped for 2 cusp verity of mandibular second premolar with predominantly bilateral existence. Frequency of 3 cusp type premolars was more in females as compared to males.

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