A study of the shape, height and location of the lingula in dry human mandibles

Aim: The present study aims to analyze the shapes of the lingula, its height and relationship with the mandibularramal landmarks.Material and Methods: Dried mandibles were included in the study without sex differentiation. The shape of thelingula was studied in 60 mandibles. In each mandible, the lingula was scored using the classification proposedby Tuli et al (2000) i.e., triangular, truncated, nodular and assimilated. 120 sides of mandibles were studied forvarious measurements, using sliding caliper.Results: The most common shape of the lingula was found to be ‘triangular’ and the least common was ‘assimilated’.The mean height of the lingula was 7.77 +1.8 mm. The mean distance of the lingula from anterior border, posteriorborder and notch of the mandibular ramus was 17.38 +2.52 mm, 15.96 +1.91 mm and 16.26 +2.36 mm respectively.Conclusion: This study provides information regarding shape, height, and location of the lingula. Thus, the studywill assist surgeons to locate the lingula and avoid intraoperative complications.

Contribuição topográfica do forame e língula mandibular em procedimentos cirúrgicos no ramo da mandíbula / Topographic contribution of the foramen and mandibular lingula in mandibular ramus surgeries

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

Measurement of mandibular lingula location using cone-beam computed tomography and internal oblique ridge-guided inferior alveolar nerve block

OBJECTIVES: Inferior alveolar nerve block (IANB) is the most frequently used treatment for mandibular molars. Successful IANB requires insertion of the dental needle near the mandibular foramen. In this study, we aimed to analyze the anatomic location of the mandibular lingula and evaluate the effects of internal oblique ridge (IOR)-guided IANB. MATERIALS AND METHODS: The location of the mandibular lingula was measured using cone-beam computed tomography images of the mandibles obtained from 125 patients. We measured the distances from the occlusal plane to the lingula and from the IOR to the lingula in 250 mandibular rami. Based on the mean of these distances, alternative anesthesia was carried out on 300 patients, and the success rate of the technique was evaluated. RESULTS: The mean vertical distance was 8.85±2.59 mm, and the mean horizontal distance was 14.68±1.44 mm. The vertical (P<0.001) and the horizontal (P<0.05) distances showed significant differences between the sex groups. The success rate of the IOR-guided technique was 97.3%. CONCLUSION: IANB-based location of mandibular lingula showed a high success rate. From this study, we concluded that analysis of the anatomic locations for mandibular lingula and IOR-guided IANB are useful for restorative and surgical dental procedures of the mandibular molars.

Anatomical study of the location of the antilingula, lingula, and mandibular foramen for vertical ramus osteotomy / 대한악안면성형재건외과학회지

BACKGROUND: The purpose of this study was to identify the location of the antilingula, lingula, and mandibular foramen in Korean cadavers and to promote safe and accurate surgery without damage to the inferior alveolar neurovascular bundle (IANB) when performing a vertical ramus osteotomy (VRO). METHODS: This study was conducted on the dried mandibles of 20 adult cadavers. Digital calipers were used to measure the distances from the anatomical reference points (antilingula, lingula, and mandibular foramen). RESULT: The antilingula was located at the anterior 44% and superior 31% in the ramus. The lingula was located at the anterior 55% and superior 30% in the ramus. The mandibular foramen was located at the anterior 58% and superior 46% in the ramus. Regarding the positional relationship with the antilingula, the lingula was located 0.54 mm superior and 4.19 mm posterior, and the mandibular foramen was located 6.95 mm inferior and 4.98 mm posterior. The results suggested that in order to prevent damage to the IANB, osteotomy should be performed in the posterior region of ramus at least 29% of the total horizontal length of the ramus. CONCLUSION: Using only the antilingula as a reference point is not guaranteed to IANB injury. However, it is still important as a helpful reference point for the surgeon in the surgical field.

Evaluation of mandibular lingula and foramen location using 3-dimensional mandible models reconstructed by cone-beam computed tomography / 대한악안면성형재건외과학회지

BACKGROUND: The positions of the mandibular lingula and foramen have been set as indexes for inferior alveolar nerve (IAN) block and ramus osteotomies in orthognathic surgery. This study aimed to evaluate the anatomical structures of mandibular ramus, especially the mandibular lingula and foramen, by analyzing the cone-beam computed tomography (CBCT) data of young adults. METHODS: We evaluated 121 sides of hemi-mandibular CBCT model of 106 patients (51 male and 55 female patients; 18 to 36 years old). All the measurements were performed using the 2- and 3-dimensional rulers of OnDemand3D® software. RESULTS: Statistical analysis of the data revealed that there was no significant difference in the mandibular angle between the genders. The mandibular lingula was found to be located at the center of ramus in males, but a little posterior in relation to the center in females. The mandibular lingula was rarely located below the occlusal plane; however, the position of the mandibular foramen was more variable (84.3% below, 12.4% above, and 3.3% at the level of the occlusal plane). CONCLUSIONS: The results of this study provide a valuable guideline for IAN block anesthesia and orthognathic surgery. CBCT can be considered effective and accurate in evaluating the fine structures of the mandible.

Analysis of the lingula shapes in macerated mandibles of Brazilian individuals / Análisis de la forma de la língula en mandíbulas maceradas de individuos brasileños

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.

Mandibular foramen location and lingula height in dentate dry mandibles, and its relationship with cephalic index / Localización del foramen mandibular y altura de la língula mandibular en mandíbulas dentadas secas, y su relación con el índice cefálico

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.

Evaluación de la anatomía mandibular relacionada con la osteotomía sagital de la rama / Evaluation of mandibular anatomy related to sagittal split ramus osteotomy

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.

A Morphometric Study on the Mandibular Foramen and the Lingula in Korean / 체질인류학회지

Interest in the correction of jaw deformities has increased due to the development of techniques and instruments of jaw operation. The accurate position of the mandibular foramen and lingula is important for the prevention of the complications and successful inferior alveolar nerve block. This study was conducted on 104 dried mandibles (65 males, 39 females) from Korean cadaver. The positions of the mandibular foramen and lingula were measured on the coronoid notch, occlusal plane, mandibular notch, gonion, koronoid and kondylion. The structures of the mandibular foramen and lingula were determined and the thickness of ramus and the angle of mandible were measured. Independent t-tests and paired t-tests were performed to determine the statistically significant difference. The results as follows; The line between coronoid notch and posterior border of ramus was located on the same level with the tip of lingula in 42.2% of the cases, and in between the mandibular foramen and the tip of lingula in 33.8% of the cases. The occlusal plane was located on the level between the mandibular foramen and the tip of lingula in 47.7% of cases, and on the same level with the tip of lingula in 35.6% of the cases. The line between lower end of the mandibular notch to inferior border of the mandible, in parallel to the posterior border of the mandibles, met the tip of lingula in 55.8% of the cases. The mandibular foramen was located posteriorly to the midpoint on the anteroposterior (AP) width of the ramus. It was located at 57.3% of AP width from the coronoid notch and 56.5% from the occlusal plane. The mandibular foramen and the tip of lingula were located superiorly to the midpoint on the vertical height of the ramus, on the 48.5% and 35.7% of vertical distance from the coronoid notch, respectively. The mandibular foramen was located at 40% of the length on the line from the gonion to the koronion. The results of this study will provide important morphometric information to prevent the complications in mandibular surgery and also provide the basis for the development of the new techniques.

Morphological analysis of the lingula in dry mandiblesof individuals in Southern Brazil

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.

A Study Of Mandibular Anatomy For Orthognathic Surgery In Koreans

Anatomical shape of the mandibular ramus, which includes the area from the rear of the mandibular second molar to the mandibular posterior border and from the mandibular sigmoid notch to the inferior mandibular border, must be carefully considered to perform orthognathic surgery. The locations of the lingula and mandibular foramen in medial side of mandibular ramus are one of the most important factors to decide the location of the horizontal medial osteotomy in sagittal split ramus osteotomy and to select the line of vertical osteotomy in intraoral vertical ramus osteotomy. Sixty-five different Korean human dry mandibles were surveyed. All mandible have permanent dentition including complete eruption of the mandibular second molar. The locations of the lingula and mandibular foramen in medial side of the ramus were identified and following results were obtained. Anterior ramal horizontal distance from lingula was 16.13+/-3.53mm(range:8.6~24.3mm), anterior ramal horizontal distance from mandibular foramen was 23.91+/-4.79mm(range: 14.1~39.7mm), horizontal width of mandibular foramen was 2.79+/-0.95mm(range: 1.5 ~6.1mm), height of lingula was 10.51+/-3.84mm(range: 3.1~22.4mm), vertical distance from sigmoid notch to lingula was 19.82+/-5.11mm(range: 9.1~35.3mm). From this study, the result could be used to select the location of osteotomy lines and to decide amount of periosteal elevation to avoid injury of neurovascular bundle, and to accomplish the appropriate split in Korean patients in mandibular orthognathic surgery.

Mandibular anatomy related to sagittal split ramus osteotomy in Koreans

Sagittal split ramus osteotomy (SSRO) is one of the surgical techniques used to correct mandibular deformities. In order to prevent many surgical anatomical problems, we observed the anatomical structures related to SSRO. In dry mandibles of Koreans, lingular tips were located somewhat posteriorly and superiorly on the mandibular ramus. On the coronal sections of mandible, the mean cortical width of facial cortex was increased toward the ramus region while the lingual cortex was thinnest in the ramus region. On the same sections, all the fusion points of the buccal and lingual cortical plate were located above the mandibular lingula and beneath the mandibular notch. So, performing the SSRO on Koreans, medial horizontal osteotomy should be done through the superior aspect of the mandibular lingula. The cut line is extended 5-8 mm posterior to the mandibular lingula to preserve sufficient cortical width to strengthen the involved osseous segments and reduce possible surgical complications.