Lobodontia: Genetic entity with specific pattern of dental dysmorphology

Abstract

A characteristic pattern of dental anomalies including cone-shaped premolars, multitubercular molar crowns, pyramidal molar roots with single root canals, shovel-shaped incisors with palatal invaginations and hypodontia usually described as lobodontia was recognised as a separate entity. Only a few family reports on this condition have been published until now. The prevalence of the condition is estimated to be less than 1:1000,000. In the present paper we tried to delineate and clarify some additional aspects of this rare genetic entity in three families with 17 affected members. This represents the largest number of cases recorded since now. The analyses of dental morphology, crown-size profile patterns, pedigree analyses, and analyses of digitopalmar dermatoglyphics were performed in 7 examined patients. Crown-size profile pattern was calculated for seven patients and compared with standards for the Croatian population. The most striking features of the condition are conical premolars, tritubercular canines, single pyramidal molar roots, multitubercular molar crowns and invaginated upper incisors. A considerable reduction of crown-size was observed for all premolars, particularly in mandible. The alveolar process in the premolar region was hypoplastic and thin in all patients studied. Gender ratio of affected individuals was approximately M1:F1. Our data suggest that the prevalence of this condition is less than 1:300,000 in the Croatian population, which is considerably higher than previously reported in the literature. The analysis of the anomaly in all the families showed a slight variability in the clinical picture and autosomal dominant (AD) mode of inheritance. It could be concluded that this rare condition described as lobodontia represents a true genetic entity which follows AD mode of inheritance and displays variability in its expression.