RESUMO

Objetivo: analisar a topografia e biometria do forame mandibular e da lingula mandibular em crânios secos para verificar sua variabilidade e determinar suas posições topográficas. Material e Método: Para analisar as distâncias, foram realizadas medições utilizando um paquímetro digital Mitutoyo® devidamente calibrado para coletar a distância em milímetros, do centro do forame até as quatro margens (anterior, posterior, superior e inferior) do ramo mandibular (N = 176). Realizamos as medidas do forame mandibular em milímetros para determinar sua geometria externa. A lingula mandibular (N = 76) foi estudada quanto à sua localização topográfica e forma quando sua estrutura é preservada. Todos os dados foram documentados em um protocolo de coleta de dados com o objetivo de desenhar diagramas esquemáticos e arquivar as fotografias dos casos e a análise dos resultados. Resultados: em relação à frequência, o forame estava presente em todos os casos (100%), em ambos os lados da superfície medial do nervo mandibular. O número de forames de cada lado é único: foram observados 175 casos (99,5%). Apenas um forame (0,5%) era o dobro do lado direito. Em relação à sua posição em relação às margens da mandíbula, na maioria delas, está localizada próxima à margem inferior, variando entre 9,6 mm e 39,1 mm, com média de 26,0 mm. A margem posterior da mandíbula variou entre 6,8 mm e 24,0 mm, com média de 12,30 mm. A lingula mandibular dos maxilares foi analisada em 32 maxilares (64 casos), com formato triangular (55%), presente na maioria dos casos (86%) e posição ântero-superior em 43% deles. Conclusões: o forame mandibular é um elemento anatômico importante para o sucesso da técnica de bloqueio do nervo alveolar inferior. Sua estrutura acessória, a lingula mandibular, é uma posição de referência em cirurgia ortognática; devido à sua localização e aspecto, serve como um escudo protetor para o feixe neurovascular alveolar inferior

Objective: to analyze the topography and biometrics of the mandibular foramen and mandibular lingula in dry skulls to verify their variability and to determine their topographic positions. Material and method: to analyze the distances, measurements were made using a properly calibrated Mitutoyo® digital caliper to collect the distance in millimeters, from the center of the foramen to the four margins (anterior, posterior, superior and inferior) of the mandibular ramus (N=176). We performed the measurements of the mandibular foramen in millimeters to determine its external geometry. The mandibular lingula (N=76) was studied regarding its topographical location and shape when its structure was preserved. All data were documented in a data collection protocol aimed at drawing schematic diagrams and archiving the photographs of the cases and the analysis of the results. Results: in relation to the frequency, the foramen was present in all cases (100%), on both sides on the medial surface of the mandibular ramus. The number of foramen on each side is unique: 175 cases (99.5%) were observed. Only one foramen (0.5%) was double on the right side. Regarding its position in relation to the margins of the jaw, in most of them, it is located near the inferior margin, having varied between 9.6mm and 39.1mm, with an average of 26.0mm. The posterior margin of the jaw varied between 6.8mm and 24.0mm, with an average of 12.30mm. The mandibular lingula of the jaws were analyzed in 32 jaws (64 cases), having triangular shape (55%), present in most cases (86%) and in anterosuperior position in 43% of them. Conclusions: the mandibular foramen is an important anatomical element for the success of the inferior alveolar nerve block technique. Its accessory structure, the mandibular lingula, is a reference position in orthognathic surgery; due to its location and aspect, it serves as a protective shield for the inferior alveolar neurovascular bundle

Assuntos

RESUMO

The lingula of the mandible is a bone projection that limits medially the mandibular foramen, which is the region where the inferior alveolar neurovascular bundle penetrates. The lingula is an important anatomical landmark used in maxillofacial surgeries and to block the inferior alveolar nerve. The aim of this study was to analyze the different types of lingula found in mandibles of Brazilian individuals, considering aspects such as gender and race. One hundred thirty-two macerated mandibles of Brazilian adult individuals of both sexes, black and white skin colors, were used. The lingula was classified into four types: triangular, truncated, nodular and assimilated. The data were analyzed using Chi-square test and Fisher's exact test. The truncated shape was the most commonly found (49 %), followed by nodular (26.5 %) and triangular (23.3 %) shapes. The assimilated shape was significantly less prevalent with 1.2 %. Each type of the lingula was more often bilateral rather than unilateral. Considering skin color we observed that the truncated shape was more prevalent in black individuals than in white individuals and the nodular shape was more prevalent in white individuals than in black individuals. There was no case of assimilated shape in black individuals. Considering gender we observed that the truncated shape was more prevalent in females than in males and the triangular shape was more prevalent in males than in females. The lingula shape showed no side preference. Our findings facilitate the planning of oral and maxillofacial surgical procedures that involve the lingula and/or the inferior alveolar neurovascular bundle, avoiding operative complications.

La língula de la mandíbula es una proyección ósea que limita medialmente el foramen mandibular, región en la cual penetra el fascículo vásculonervioso. Es un importante punto de referencia en cirugías maxilofaciales, utilizado en cirugías y en el bloqueo del nervio alveolar inferior. El objetivo fue analizar los diferentes tipos de língula encontrados en mandíbulas de individuos brasileños, considerándose aspectos como sexo y raza. Fueron utilizadas 132 mandíbulas maceradas de individuos brasileños adultos de ambos sexos, leucodermas y melanodermas. Se clasificó la língula en cuatro tipos: triangular, truncada, nodular y asimilada. Para el análisis estadístico se utilizó el Chi-cuadrado y la prueba exacta de Fisher. La forma truncada fue la más frecuente (49 %), seguida de la nodular (26,5 %) y triangular (23,3 %). La forma asimilada fue menos prevalente, con el 1,2%. Cada tipo de língula fue más común bilateral. Considerando el color de piel se observó que la forma truncada fue más prevalente en melanodermas que en leucodermas y la forma nodular fue más prevalente en leucodermas que en melanodermas. No se encontró la forma asimilada en individuos melanodermas. Considerando el sexo, se observó que la forma truncada fue más frecuente en mujeres que en hombres y la forma triangular más frecuente en hombres que en mujeres. La forma de la língula mostró no tener preferencia por lado. Nuestros hallazgos facilitan la planificación de los procedimientos quirúrgicos orales y maxilofaciales que implican la língula y/o el paquete neurovascular alveolar inferior, evitando complicaciones operatorias.

Assuntos

RESUMO

The mandibular foramen and its lingula is a major landmark when administering anesthetic or performing surgical procedures. The objective of this study was to determine whether the topological features of the mandibular foramen (MF) and lingula varied in mandibles from skulls of different cephalic indexes. The location of the mandibular foramen referred to the longitudinal borders of the mandibular ramus (MR), height of the foramen (Hf) referred to the occlusal line of the second molar, and the height of the lingula (Hl) were determined in a total of one hundred and five dry mandibles from skulls identified as dolicho- meso- and brachycephalic. On average MF in brachycephalic mandibles was closest to the anterior border of MR. Hf in brachy-, meso- and dolichocephalic mandibles were -0.22 mm, -4.04 mm and -4,01mm, respectively. The lingula in brachycephalic specimens was considerably shorter (0.78 mm) than in dolichocephalic ones (1.84 mm). Inferior alveolar nerve block should be carried out using shorter needles, inserting it 4mm above the occlusion level of the molar teeth. The ramus of brachicephalic mandibles were significantly less wide those of dolicho- and mesocephalic ones. If the height of the lingula is to be used as a reference to judge the level of the medial horizontal cut to carry out sagittal split ramus osteotomy, special attention should be given to the patient's cephalic index.

El foramen mandibular y la língula son los puntos anatómicos más importantes a considerar en la administración de anestesia troncular o la realización de procedimientos quirúrgicos en la mandíbula. El objeivo fue determinar si las características topológicas del foramen mandibular (FM) y la língula mandibular presentan variaciones en las mandíbulas de cráneos con diferentes índices cefálicos. Fueron utilizados 105 mandíbulas secas, pertenecientes a cráneos identificados como dolico, meso y braquicéfalos. En cada caso, se relacionaron la ubicación del FM con los márgenes longitudinales de la rama mandibular (RM) y la altura del foramen (Af) con la línea oclusal del segundo molar. Además, se determinó la altura de la língula (Al). En promedio, el FM de mandíbulas braquicefálicas se encontró más cerca del margen anterior de la RM. La Af en mandíbulas braqui, meso y dolicocéfalas fue de -0,22 mm, -4,04 mm y -4,01 mm, respectivamente. La língula mandibular en muestras braquicefálicas, fue considerablemente más corta (0,78 mm) que en las dolicocéfalas (1,84 mm). El bloqueo del nervio alveolar inferior debe llevarse a cabo usando agujas cortas, insertándolas 4 mm por encima del nivel de oclusión de los dientes molares. La rama de las mandíbulas braquicefálicas fueron significativamente menos anchas que en cráneos dolico y mesocefálicos. Si la altura de la língula mandibular se utilizará como referencia para determinar el nivel del corte medial horizontal para realizar la osteotomía sagital de la rama mandibular, se debe dar especial atención al índice cefálico del paciente.

Assuntos

RESUMO

La osteotomía sagital de la rama mandibular (SSRO) es una de las técnicas quirúrgicas más frecuentes para corregir las deformidades de la mandíbula. Con el fin de prevenir problemas anatómicos y quirúrgicos, los cirujanos requieren una mayor investigación sobre las estructuras anatómicas relacionadas con la SSRO. El objetivo de este estudio fue investigar las posiciones de la antilingula (AL), la entrada al nervio alveolar inferior (NAI) en la mandíbula y otros puntos de referencia anatómicos en relación con la língula mandibular (L). Fueron estudiadas 70 hemimandíbulas secas. La AL y los demás puntos de referencia y, la posición correspondiente de la L se marcaron en la cara medial y lateral de la rama mandibular respectivamente. Fueron medidas las distancias de la AL, NAI y L en los planos anterior-posterior y superior-inferior con un caliper, y se estableció su relación geométrica. Los resultados mostraron que la AL era perceptible en el 100 por ciento de las caras laterales mandibulares. La mayoría de las ALs se encuentran anterior a la L, con una distancia media de 0,66+/-2,43mm y 0,92+/-2,56 mm y, 4,23+/-2,97 mm y 3,62 +/- 3,14 mm superior a ella (lados derecho-izquierdo respectivamente) (ambos con un valor de p <0,001). Valores similares se observaron en relación con el NAI. No se encontraron diferencias significativas entre los lados derecho e izquierdo, para la mayoría de los parámetros. Los parámetros estudiados pueden asistir a los cirujanos maxilofaciales a determinar la proximidad anatómica del NAI, y reducir al mínimo el riesgo de dañar el nervio y vasos sanguíneos. No recomendamos el uso de la AL como única referencia anatómica cuando se realiza un procedimiento de SSRO.

Sagittal split ramus osteotomy (SSRO) of the mandible is one of the most common surgical techniques to correct mandibular deformities. In order to prevent many surgical anatomical problems, surgeons have found that further investigation of the anatomical structures related to SSRO is needed. This study aims to investigate positions of the antilingula (AL), inferior alveolar nerve (IAN) and other anatomic landmarks in relation to the lingula of dried mandibles. 70 Chilean dried hemimandibles were studied. The AL, others landmarks and the corresponding position of the L were marked on the internal and external aspect of the mandibular ramus respectively. The distances from the AL, IAN and L were measured in the anterior­posterior and the superior­inferior planes using a digital caliper and geometric relationship was established. The results showed the AL was discernible in 100 percent of lateral mandibular rami studied. The most of the AL was found anteriorly to the L with a mean distance of 0.66+/-2.43mm and 0.92+/-2.56mm, and 4.23 +/- 2.97mm and 3.62+/-3.14mm superiorly (right-left sides respectively) (both with p value <0.001). Similar values were seen in relation with IAN. No significant differences were found between the right and left sides, for the majority of parameters. The studied parameters will assist clinicians to determine the anatomical proximity to the IAN, and, minimize the risk of damaging nerver and vessels. We do not recommend the use of antilingula as only anatomical landmark when performing a SSRO procedure.

Assuntos

RESUMO

The lingula of the mandible is a small-tongue-shaped bone projection overlaying the mandibular foramen, andit is clinically significant in oral and maxillofacial surgical procedures. This study aims to analyze the shapesof the lingula and its relationship with the surface of the mandibular ramus, and to record data about thepopulation in Southern Brazil. The maxillofacial study of the lingula in 80 dry mandibles in adult individualswas conducted. The lingula of the two rami of each mandible were assessed and classified in the followingshapes: triangular, truncated, nodular and assimilated. The triangular shape was analyzed according to itsdirection in relation to the condyle or the posterior region of the mandible posterior ramus, and also accordingto its relationship with the inner surface of the mandibular ramus: assimilated, free or partially free. Theoccurrence of accessory mandibular foramens in each mandibular ramus was also recorded. The triangularshape of the lingula was found in 66 sides (41.3%), seeing that in 21 mandibles (42 sides) it was noticed bothon the right side and the left side, whereas 13 occurred on the right side and 11 on the left side, unilaterally.The truncated lingula was present on 58 sides (36.3%), and the nodular lingula was noticed on 17 sides(10.5%); as to the assimilated lingula it was found on 19 sides (11.9%). Accessory foramens were foundin 11.3 and 3.8% of the right and left mandibular rami, respectively. Considering that the lingula showsmorphological variants in different populations, these results include significant data of the population in theSouth of Brazil regarding the morphometric study of the mandible, also playing a role to avoid failure of theanesthetic surgical block of the inferior alveolar nerve.

Assuntos