Frecuencia y caracterización de foramen mental accesorio en una población chilena mediante tomografía computarizada de haz cónico / Frequency and characterization of accessory mental foramen in a Chilean population using cone beam computed tomography

RESUMEN: En la práctica clínica odontológica, reconocer estructuras anatómicas es determinante en la planificación de distintos tratamientos que involucren algún riesgo. Uno de los exámenes complementarios recomendados para la planificación de diferentes tratamientos en odontología es la Tomografía Computarizada de Haz Cónico (CBCT). Con este examen, se pueden pesquisar variantes anatómicas como el Foramen Mental Accesorio (FMA), el cual es importante identificar para prevenir complicaciones. El objetivo de este trabajo fue determinar la frecuencia y caracterización de FMA en una población chilena adulta, de la ciudad de Valdivia, Chile. Este estudio es de tipo observacional descriptivo. Se revisaron 247 exploraciones de diferentes centros radiológicos de la ciudad de Valdivia, cumpliendo 143 con los criterios de selección. Este estudio fue aprobado por el Comité ético científico del Servicio de Salud de Valdivia. Se encontró presencia de FMA en el 17,48 % que corresponde a 25 pacientes de un total de 143, correspondiendo un 80 % al sexo femenino. El rango etario en que se encontró con mayor frecuencia correspondió a 18-39 años. La distancia promedio entre FMA y FM (Foramen Mental) fue de 5,76 mm, correspondiendo a 2 mm la distancia mínima y 11,5 mm la distancia máxima. La distancia promedio entre FMA y ápice dentario más cercano fue de 5,36 mm. La distancia mínima y máxima fueron de 0,8 mm y 10,2 mm respectivamente. El ápice radicular mayormente asociado al FMA correspondió al segundo premolar con una frecuencia de 60 % (n=15). Este estudio confirma la importancia de la correcta evaluación de la región mental ante procedimientos en la zona, la cual es vital para prevenir lesiones en relación a esta variante anatómica.

SUMMARY: The recognition of key anatomical structures is decisive to avoid complications in the dental clinical practice. Cone Beam Computed Tomography (CBCT) is a complementary exam recommended for the planning of different procedures in dentistry. With this exam, anatomical variants can be identified, such as the Accessory Mental Foramen (AMF). The objective of this work was to determine the frequency and characteristics of AMF in an adult Chilean population from the city of Valdivia, Chile. This is an observational study that included 247 CBCT exams from different radiological centers in Valdivia. According to the selection criteria, 143 CBCT exams were included. This study was approved by the Scientific Ethics Committee of the Valdivia Health Services. AMF was identified in 25 patients representing 17.48 %. From this result, 80 % were found in females. AMF was most frequently identified in patients from 18 to 39 years old. The average distance between AMF and Mental Foramen (MF) was 5.76 mm, which corresponds to 2 mm the minimum distance and 11.5 mm the maximum distance. The average distance between AMF and the nearest dental apex was 5.36 mm, and the minimum and maximum distance were 0.8 mm and 10.2 mm, respectively. The root apex of the second premolar was most frequently associated with the AMF, representing 60 % (n=15). This study confirms the importance of the correct evaluation of the mental region before initiating procedures in the area, which is vital to prevent injuries associated with this anatomical variant.

Characterization of individuals at high risk of developing melanoma in Latin America: bases for genetic counseling in melanoma.

PURPOSE: CDKN2A is the main high-risk melanoma-susceptibility gene, but it has been poorly assessed in Latin America. We sought to analyze CDKN2A and MC1R in patients from Latin America with familial and sporadic multiple primary melanoma (SMP) and compare the data with those for patients from Spain to establish bases for melanoma genetic counseling in Latin America. METHODS: CDKN2A and MC1R were sequenced in 186 Latin American patients from Argentina, Brazil, Chile, Mexico, and Uruguay, and in 904 Spanish patients. Clinical and phenotypic data were obtained. RESULTS: Overall, 24 and 14% of melanoma-prone families in Latin America and Spain, respectively, had mutations in CDKN2A. Latin American families had CDKN2A mutations more frequently (P = 0.014) than Spanish ones. Of patients with SMP, 10% of those from Latin America and 8.5% of those from Spain had mutations in CDKN2A (P = 0.623). The most recurrent CDKN2A mutations were c.-34G>T and p.G101W. Latin American patients had fairer hair (P = 0.016) and skin (P < 0.001) and a higher prevalence of MC1R variants (P = 0.003) compared with Spanish patients. CONCLUSION: The inclusion criteria for genetic counseling of melanoma in Latin America may be the same criteria used in Spain, as suggested in areas with low to medium incidence, SMP with at least two melanomas, or families with at least two cases among first- or second-degree relatives.Genet Med 18 7, 727-736.