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Mandibular premolar differentiation
Author(s) -
Carlsen Ole,
Alexandersen Verner
Publication year - 1994
Publication title -
european journal of oral sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.802
H-Index - 93
eISSN - 1600-0722
pISSN - 0909-8836
DOI - 10.1111/j.1600-0722.1994.tb01159.x
Subject(s) - orthodontics , premolar , medicine , dentistry , molar
The authors present a method for differentiating between human mandibular premolars: P1 inf and P2 inf. The material with which the method was developed consisted of 260 stone casts. On these, both premolars were present and were intact on at least one side. The study models represented 131 girls and 129 boys, mean age 14.6 yr. In a comprehensive pilot project, a whole range of macromorphologic criteria was tested that, in various combinations, could be expected to be usable for differentiation between P1 inf and P2 inf. On the basis of the pilot study, the total variation was reduced to four criteria‐combinations, called types, which, in summary, can be characterized as the following: type 1: flattening of the mesiolingual part of the crown, no lingual lobe; type 2: at least one lingual lobe; type 3: lingual part of the crown symmetrically curved, no lingual lobe; type 4: other characteristics. After definition of the types, their occurrence on P1 inf and P2 inf was definitively registered. Observations were made with a stereomicroscope; 131 premolar pairs from the right side and 129 from the left were registered. Statistical tests showed that there was no significant difference in the distribution of types between variants from the right and left sides, or between girls and boys. These data were therefore pooled for P1 inf and P2 inf, respectively. A subsequent test revealed, as expected, a highly significant difference in the distribution of the four types among 1. and 2. premolar. For estimation of the degree of certainty when the types concerned were used for differentiation, 95% confidence limits were set up from the observed frequencies. Results of these statistical analyses can be described as follows: the probability that a mandibular premolar of type 1 was a 1. premolar was 0.96 (0.93–0.98), that a type 2 variant was a 2. premolar was 0.99 (0.96–1.00), that a type 3 variant was a 2. premolar was 0.79 (0.58–0.93), and that a type 4 variant was a 2. premolar was 0.92 (0.74–0.99). The target groups of this publication are clinical dentists, forensic odontologists, dental anthropologists, and dental morphologists.