International Journal of Morphology
On-line version ISSN 0717-9502
GARCIA-HERNANDEZ, Fernando and ARANEDA RODRIGUEZ, Claudia Patricia. Third Molar Agenesis in Patients of Dental Clinic of the Universidad de Antofagasta, Chile. Int. J. Morphol. [online]. 2009, vol.27, n.2, pp. 393-402. ISSN 0717-9502. http://dx.doi.org/10.4067/S0717-95022009000200014.
Agenesis is defined as the absence of teeth by genetic alterations isolated or syndromic. Agenesis of third molar is associated to malformations and is considerate by diverse authors as a consequence of human evolution (Larmour et al, 2005). The third molars are teeth with higher prevalence of agenesis together with seconds premolars and lateral incisive (Fuller & Denehy, 1984). The prevalence varies between 9% to 37% (McNamara & Foley, 2006). Arboleda et al. (2006) indicated a prevalence of 20%. The literature notes statistical variables percentage by gender, dental arch, side, and tooth, with few articles on groups originating from Chile. The population in study consisted of 52 men and 48 women between 14 and 26 years old, patients of the dental clinic of the Universdad de Antofagasta. All individuals were healthy, without any general or maxillofacial malformation without infectious diseases affecting the odontogenesis and dental eruption, without extractions of third molar and orthodontic treatment prior to the panoramic x-ray. A 20% of individuals with agenesis was determined, with 8.25% of agenesis respect the total number of third molars and 1.03% agenesis respect the total number of teeth. Statistical analyses did not show significant differences at 95% level, with agenesis of third molar prevalence in females, in maxilla, in the left side, simple, being the left maxillary third molar the tooth that present many number of agenesis.
Keywords : Anthropology; Dentistry; Agenesis; Third molar.