Pyramidal and Taurodont Molars and Their Association With Other Tooth Anomalies.

PURPOSE: Determine the prevalence of pyramidal molars (PMs), associated tooth anomalies, and medical conditions (MC).

METHODS: Pantomograms from 10,168 subjects were searched for PMs.

RESULTS: A total of 148 individuals (75.7 percent females), aged 9.7 to 18.9 years old, had PMs. Subjects with MCs (53.4 percent) had on average 17 percent more PMs (P=.0476) and 2.8 times greater odds of palatally displaced canines (P=.0309). The mean number of pyramidal and taurodont molars per subject was 2.9±1.4 (SD) and 3.1±1.7 (SD), respectively. In both sexes, 63.5 percent of all observed PMs were located in the maxilla and 78.5 percent of all PMs were second molars. Taurodont molars increased by 9.4 percent as other tooth anomalies increased by one, but decreased by 8.2 percent for each additional PM. Tooth anomalies associated with PMs were palatally displaced canines (17.6 percent) and short root anomaly of maxillary central incisors (6.1 percent). Delayed eruption was noted in 9.5 percent, tooth agenesis in 6.1 percent, and supernumerary teeth in 3.4 percent.

CONCLUSIONS: The prevalence of pyramidal molars was 1.4 percent, and the female-to-male ratio was 3.1 to one. Pyramidal molars are often associated with medical conditions and other tooth anomalies.