CBCT study of root apices distance to mandibular canal in peruvian population

The purpose of this study was to compare the average distances from the root apices of the first molars, second molars, and second premolars to the mandibular canal according to sex in the Peruvian population using cone-beam computed tomography (CBCT). Eighty CBCT scans of Peruvian patients aged from 15-80 years were examined. After locating the mandibular canal, measurements of the vertical distances from the mandibular canal to the apices of the second premolars, as well as the first molars and second molars, were made. For the statistical analysis, Student's t test was used for both paired and unpaired samples, with a significance level of p0.05) between the distances from the apices of the second premolars and the first and second molars to the mandibular canal. However, for the second premolars and second molars on the left side, the values were higher, with averages of 5.52mm and 3.75mm, respectively. The mesial roots of the second molars were closer to the mandibular canal. In addition, women showed shorter distances than men.

El propósito de este estudio fue comparar las distancias promedio desde los ápices radiculares de primeros molares, segundos molares y segundos premolares al canal mandibular según sexo en la población peruana mediante tomografía computarizada de haz cónico (TCHC). Se examinaron 80 tomografías CBCT de pacientes peruanos con edades comprendidas entre los 15 y 80 años. Luego de ubicar el canal mandibular, se realizaron mediciones de las distancias verticales desde el canal mandibular hasta el ápice de los segundos premolares mandibulares, así como de los primeros molares y segundos molares. Para el análisis estadístico se utilizó la prueba t de Student para muestras pareadas y no pareadas con un nivel de significación de p0.05) entre las distancias desde los ápices de los segundos premolares mandibulares y los primeros y segundos molares al canal mandibular. Sin embargo, para los segundos premolares y segundos molares en el lado izquierdo, los valores fueron más altos con un promedio de 5,52mm y 3,75mm, respectivamente. Las raíces mesiales de los segundos molares estaban más cerca del canal mandibular. Además, las mujeres mostraron distancias más cortas que los hombres.

Complicaciones de la técnica anestésica mandibular Spix en la clínica odontológica de la Universidad Andrés Bello / Incidence of complications of mandibular anesthetic Spix techniques in the Andrés Bello University dental clinic

Objetivo: Determinar la incidencia de complicaciones de la técnica anestésica Spix en procedimientos odontológicos a pacientes atendidos en la clínica de la Universidad Andrés Bello (UNAB). Material y Métodos: Se analizó a 37 pacientes que fueron atendidos por alumnos de cuarto y quinto año de la clínica odontológica, a los cuales se le realizó la técnica anestésica Spix para realizar el procedimiento odontológico. Se consignó mediante la observación la presencia de formación de hematomas intraorales en el sitio de punción, rotura de la aguja, cantidad de tubos de solución anestésica inyectados, presencia de dolor a la inyección de solución anestésico y la presencia o no de parálisis facial. Mediante la recolección de datos y posterior encuesta a los participantes se consignó la presencia de trismus al día siguiente de la atención y parestesia persistente al día siguiente de la atención. Resultados: De 37 pacientes estudiados que recibieron la técnica anestésica Spix, 6 presentaron hematoma intraoral (16,2%), ninguno reportó rotura de la aguja, 1 presentó parálisis facial (2,7%), 1 presentó parestesia persistente al día siguiente (2,7%), 12 presentaron trismus posterior a la inyección (32,4%). El rango de dolor reportado fue entre 1 y 4 según la escala EVA. Conclusión: Hay una baja incidencia de las complicaciones asociadas a la técnica anestésica Spix en la clínica odontológica de la UNAB, siendo el trismus la complicación más frecuente. Se necesita un mayor número de muestra para entender mejor esta realidad.

Objective: To determine the incidence of complications of the Spix anesthetic technique in the dental procedures of patients attended at the Andrés Bello University dental clinic. Material and Methods: 37 patients who were cared for by fourth- and fifth-year students from the dental clinic of the Andrés Bello University were analyzed, who underwent the Spix anesthetic technique to perform the dental procedure. The presence of intraoral hematoma formation at the puncture site, needle breakage, number of injected anesthesia tubes, presence of pain upon injection of anesthetic and the presence or not of facial paralysis were recorded. Through data collection and subsequent survey of the participants, the presence of trismus was recorded the day after care. Results. Of the 37 cases of patients studied who received the Spix anesthetic technique, 6 had intraoral hematoma (16.2%), no needle break was reported, 1 had facial paralysis (2.7%), 1 had persistent paresthesia at the next day (2.7%), 12 presented trismus after the injection (32.4%), the pain range was between 1 and 4 according to the VAS scale. Conclusion. There is a low incidence of complications associated with the Spix anesthetic technique in the Andrés Bello University dental clinic, trismus being the most frequent (32.4%). A larger sample number should be needed to better understand this reality.

Prevalência de radiolucência justa-apical e sua relação com terceiros molares inferiores em radiografias panorâmicas / Prevalence of juxta-apical radiolucency and association/relations with the lower third molar in panoramic radiography

Objetivo: Avaliar a prevalência da radiolucência justa-apical (RJA) e sua relação com os terceiros molares inferiores, em 1054 radiografias panorâmicas. Métodos: A amostra foi constituída por radiografias panorâmicas digitais de indivíduos maiores de 18 anos, com pelo menos um terceiro molar inferior. As imagens foram analisadas para a presença de RJA em relação à corticalização, localização, relação com o canal mandibular, angulação e profundidade de impactação do terceiro molar. Os dados foram analisados através de estatística descritiva e pelo teste Qui-quadrado, sendo que valores de p < 0,05 foram considerados como significativos. Resultados:Foi encontrada uma prevalência de 2,75% de RJA, sendo predominante no sexo feminino (p = 0,01). A RJA foi visualizada em maior número corticalizada (58,63%), lateroapical (48,27%), em dentes parcialmente intraósseo (68,97%) e mesioangulados (55,17%). Em relação ao canal mandibular, houve maior prevalência na posição sobreposta ao canal mandibular (65,52%). Conclusão: A prevalência de RJA foi de 2,75% do total de 1054 radiografias panorâmicas avaliadas. Em relação ao canal mandibular, apresentou maior prevalência sobreposto. Além disso, a maior parte das RJA se apresentaram corticalizadas, em posição lateroapical, associada a dentes em posição mesioangular. Descritores: Radiografia panorâmica. Dente serotino. Nervo mandibular.Prevalência de radiolucência justa-apical e sua relação com terceiros molares inferiores em radiografias panorâmicas

Aim: To evaluate the prevalence of juxta-apical radiolucency (JAR) and its relationship with the lower third molars and adjacent structures, in 1,054 panoramic radiographs. Methods: The sample consisted of digital panoramic radiographs of individuals over 18 years of age, with at least one lower third molar. The images were analyzed for the presence of JAR in relation to corticalization, location, impaction depth, relationship with the mandibular canal, angulation, and impaction of the third molar. Data were analyzed using descriptive statistics and the chi-square test, and values of p < 0.05 were considered significant.Results: A prevalence of 2.75% of JAR was found, with a statistical difference between JAR and gender (p = 0.01), which proved to be predominant in females. The JAR was seen in greater numbers as corticalized (58.63%), lateroapical (48.27%), and mesioangulated (55.17%), as well as in erupted teeth (31.03%). In relation to the mandibular canal, it presented a higher prevalence when superimposed upon the mandibular canal (65.52%). Conclusions:The prevalence of RJA was 2.75% of the 1,054 evaluated panoramic radiographs. In relation to the mandibular canal, it presented a higher prevalence of superimposition. In addition, most of the RJA were corticalized, in a lateroapical position, associated with teeth in a mesioangular position. Uniterms: Panoramic radiography. Third molar. Mandibular nerve.

Simultaneous innervated and vascularized iliac bone flap for reconstructing mandible and nerve defects / 口腔疾病防治

@#The functional reconstruction of large maxillofacial defects is a major issue in oral and maxillofacial surgery, and autologous bone transplantation is the main method. However, bone is readily absorbed following an autologous bone transplant. Even with vascular anastomosis, spontaneous osteoporosis of transplanted bone is still serious, which affects dental implantation and functional recovery. Therefore, osteoporosis of the grafted bone has become one of the main complications of jaw reconstruction, and there is no preventive measure. The problem that autologous bone with sufficient blood supply cannot avoid osteoporosis suggests that systemic factors such as nerves, which have been neglected in traditional methods, may regulate the internal environment of the transplanted bone. Based on previous studies on the regulation of mesenchymal stem cells by the neural microenvironment, we initiated a new surgical procedure for innervated and vascularized iliac bone flaps based on animal model and cadaver studies. In the innervated and vascularized iliac bone flap, vascular microanastomosis was performed in conjunction with microneuronal anastomosis between the simultaneously harvested ilioinguinal nerve (which innervates the iliac bone and is usually sacrificed and neglected in the conventional vascularized iliac bone flap) and the inferior alveolar nerve proximally and with the mental nerve distally. By conducting clinical retrospective studies and prospective randomized controlled trials, we proved that the novel method of simultaneous innervated iliac bone transplantation can not only prevent bone resorption but also restore the sensation of adjacent soft tissues such as the lip. This may solve the key problems of sensory loss and osteoporosis after mandibular reconstruction, ensure the success of dental implant dentures, and put forward the new concept of "blood supply + innervation" bi-system bone transplantation.

Risco de lesão do ramo mandibular do nervo trigêmeo na fratura de mandíbula: um estudo anatômico / Risk of injury to the mandibular branch of the trigemal nerve in jaw fracture: an anatomical study

O nervo mandibular V3 é a terceira divisão do nervo trigêmeo, apresenta fibras motoras e sensitivas, sendo a ramificação mista deste nervo. Seus ramos eferentes são responsáveis pela motricidade dos músculos mastigatórios, inerva os músculos milo-hióideo, ventre anterior do digástrico, tensor do véu palatino e tensor do tímpano. Suas fibras aferentes são responsáveis pela sensibilidade da região inferior da face e cavidade oral, dentes inferiores, parte da língua e propriocepção da cápsula da articulação temporomandibular ATM. O objetivo deste estudo é explanar as possíveis lesões no nervo mandibular, suas ramificações e estruturas adjacentes no caso de fraturas na mandíbula, colaborando com informações detalhadas para posterior estudo de acadêmicos e cirurgiões dentistas. Foi realizada uma pesquisa de campo, exploratória e descritiva, com abordagem quanti-qualitativa, para descrição e análise do trajeto do V3 até a sua chegada no osso mandibular, assim como de estruturas que compõem a topografia adjacente a mesma utilizando uma hemiface intacta de um cadáver do sexo masculino no Laboratório de Anatomia Humana das Faculdades Nova Esperança, na cidade de João Pessoa. Devido à proximidade do nervo mandibular com o processo coronoide, fraturas nesta parte do osso mandíbula, podem ocasionar lesões no V3, além de traumas no osso temporal, e consequentemente de todo o gânglio trigeminal. Além destas, estruturas adjacentes como a glândula parótida, artérias maxilar e facial, ATM, e os nervos alveolar inferior, mentual e lingual, podem ser lesionadas em uma fratura mandibular. As lesões nestes nervos, podem resultar em redução grave da qualidade de vida e dor crônica, gerando desconfortos para o paciente. Diante do exposto fica evidente a importância de conhecer a anatomia topográfica da mandíbula e suas estruturas vasculonervosas, seu trajeto e a localização. Houve dificuldade na discussão devido à escassez da literatura em relação à temática proposta. Dessa forma, é necessário motivar novos estudos sobre a temática a fim de ampliar o conhecimento dos profissionais de saúde e estimular novas técnicas para diagnóstico precoce e melhorar os resultados terapêuticos, impactando positivamente na sobrevida de pacientes com fraturas de mandibulares(AU)

The mandibular nerve V3 is the third division of the trigeminal nerve, has motor and sensory fibers, being the mixed branch of this nerve. Its efferent branches are responsible for the motricity of the masticatory muscles, innervating the mylohyoid muscles, anterior belly of the digastric, soft palate tensor and tympanic tensor. Its afferent fibers are responsible for the sensitivity of the lower face and oral cavity, lower teeth, part of the tongue and proprioception of the capsule of the temporomandibular joint TMJ. The aim of this study is to explain the possible injuries to the mandibular nerve, its ramifications and adjacent structures in the case of mandible fractures, collaborating with detailed information for further study by academics and dentists. A field research, exploratory and descriptive, with a quantitative-qualitative approach, was carried out to describe and analyze the path of the V3 until its arrival in the mandibular bone, as well as structures that make up the topography adjacent to it using na intact hemiface of a male cadaver at the Human Anatomy Laboratory of Faculdades Nova Esperança, in João Pessoa city. Due to the proximity of the mandibular nerve with the coronoid process, fractures in this part of the mandible bone can cause injuries to the V3, in addition to trauma to the temporal bone, and consequently to the entire trigeminal ganglion. In addition to these, adjacent structures such as the parotid gland, maxillary and facial arteries, TMJ, and the inferior alveolar, mental and lingual nerves can be injured in a mandibular fracture. Damage to these nerves can result in severely reduced quality of life and chronic pain, causing discomfort for the patient. Given the above, the importance of knowing the topographic anatomy of the mandible and its vascular-nervous structures, its path and location is evident. There was difficulty in the discussion due to the scarcity of literature regarding the proposed theme. Thus, it is necessary to motivate further studies on the subject in order to expand the knowledge of health professionals and encourage new techniques for early diagnosis and improve therapeutic results, positively impacting the survival of patients with mandibular fractures(AU)

Terapia de fotobiomodulação no tratamentode lesões no nervo alveolar inferior / Photobiomodulation therapy in the treatment of inferior alveolar nerve injuries

Objetivo: Realizar uma revisão integrativa da literatura acerca da eficácia da terapia de fotobiomodulação na amenização dos distúrbios neurossensoriais e da dor em pacientes com lesões no nervo alveolar inferior. Materiais e métodos: Para a pesquisa dos artigos foram utilizadas as bases de dados MEDLINE, LILACS, BBO, IBECS e SciELO com descritores em inglês combinados com os operadores booleanos. A busca limitou-se a artigos nos idiomas inglês, português ou espanhol, publicados nos últimos 10 anos, do tipo ensaios clínicos. Revisão de literatura: Nove artigos preencheram os critérios de inclusão, sendo oito ensaios clínicos randomizados e um ensaio clínico não randomiza-do. Os melhores resultados foram observados em testes de sensibilidade geral utilizando a Escala Visual Analógica. Os estudos atestaram melhora da condição independentemen-te do tempo pós-operatório, contudo, o início antecipado da terapia trouxe maiores benefícios. Ademais, embora a maioria dos artigos tenha apontado eficácia do tratamento, notou-se grande variabilidade nos protocolos de terapia a laser. Conclusão: O emprego da terapia de fotobiomodulação é eficaz no tratamento de injúrias iatrogênicas no nervo alveolar inferior. Entretanto, mais estudos são necessários a fim de estabelecer um protocolo para o uso do laser.

Objective: Conduct an integrative review of literature on the efficacy of photobiomodulation therapy in the aestheization of sensorineural disorders and pain in patients with lesions in the inferior alveolar nerve. Materials and methods: Medline, LILACS, BBO, IBECS and SciELO databases were used to search the articles with English descriptors combined with the boolean operators. The search was limited to articles in English, Portuguese or Spanish, published in the last 10 years, of the type clinical trials. Literature review: Nine articles met the inclusion criteria, eight randomized clinical trials and one non-randomized clinical trial. The best results were observed in general sensitivity tests using the Visual Analog Scale. Studies attested to an impro-vement in the condition regardless of postoperative time, however, early initiation of therapy brought greater benefits. Furthermore, although most articles have pointed out treatment efficacy, there was great variability in laser therapy protocols. Conclusion: The use of photobiomodulation therapy is effective in the treatment of iatrogenic injuries to the inferior alveolar nerve. However, more studies are needed in order to establish a protocol for the use of laser.

A cone-beam computed tomography study to assess anterior loop and other anatomic variations in mental foramen area in an iranian population / Un estudio de tomografía computarizada de haz cónico para evaluar el asa anterior y otras variaciones anatómicas en el área del foramen mentoniano en una población iraní

Purpose: This study aimed to determine the prevalence and length of the anterior loop (AL) of the inferior alveolar nerve, and evaluate the emergence direction of the mental nerve and the location of mental foramen in a group of Iranian patients. Material and Methods: This study was carried out on CBCT scans of 150 patients (57 males and 93 females; mean age 40.8 ±14.33 years). The presence and extent of the AL was determined in reconstructed images. The emergence path of the mental nerve was classified into three groups: anteriorly directed emergence, right-angled pattern of emergence, and posteriorly directed emergence. The location of mental foramen relative to adjacent premolars was determined. Results: AL was identified in 14.7% of the cases with a mean length of 1.39± 0.91 mm (range 0.25 to 3.50 mm). No significant differences were observed in the prevalence and extent of the AL between genders (p>0.05). The right-angled pattern of emergence was more dominant (43.7%). The most prevalent location of mental foramen was between the first and second premolars (68.3%). There was no significant association between the presence of AL with the path of emergence of the mental nerve (p=0.627) or the location of the mental foramen (p= 0.10 0). Conclusion: The prevalence of anterior loop was relatively low in the present sample (14.7%) with a length range of 0.25 to 3.5 mm. Due to the importance of this anatomic variation in implant surgery, it is suggested to carefully assess CBCT images before the surgical procedure to avoid neurosensory complications.

Propósito: Este estudio tuvo como objetivo determinar la prevalencia y la longitud del loop anterior (LA) del nervio alveolar inferior, y evaluar la dirección de emergencia del nervio mentoniano y la ubicación del foramen mentoniano en un grupo de pacientes iraníes. Material y Métodos: Este estudio se llevó a cabo en exploraciones de tomografía computarizada de haz cónico de 150 pacientes (57 hombres y 93 mujeres; edad media 40,8 ± 14,33 años). La presencia y extensión de la LA se determinó en imágenes reconstruidas. La vía de emergencia del nervio mentoniano se clasificó en tres grupos: emergencia dirigida anteriormente, patrón de emergencia en ángulo recto y emergencia dirigida posteriormente. Se determinó la ubicación del foramen mentoniano en relación con los premolares adyacentes. Resultados: Se identificó LA en el 14,7% de los casos con una longitud media de 1,39± 0,91 mm (rango 0,25 mm a 3,50 mm). No se observaron diferencias significativas en la prevalencia y extensión de la AL entre sexos (p>0,05). El patrón de emergencia en ángulo recto fue más dominante (43,7%). La localización más prevalente del foramen men-toniano fue entre el primer y segundo premolar (68,3%). No hubo asociación significativa entre la presencia de AL con la vía de emergencia del nervio mentoniano (p=0,627) o la ubicación del foramen mentoniano p=0,100).Conclusión: La prevalencia de asa anterior fue rela-tivamente baja en la presente muestra (14,7%) con un rango de longitud de 0,25 mm a 3,5 mm. Debido a la importancia de esta variación anatómica en la cirugía de implantes, se sugiere evaluar cuidadosamente las imágenes de tomografía computarizada de haz cónico antes del procedimiento quirúrgico para evitar complicaciones neurosensoriales.

Factors associated with root migration after lower third molar coronectomy - preliminary results / Fatores associados com a migração radicular após coronectomia de terceiros molares inferiores - resultados preliminares

Objective: The aim of this prospective study, with preliminary results, was to evaluate factors related with root migration after lower third molar coronectomy, especially radiographic bone density. Material and Methods:Twenty-two patients were submitted to 31 lower third molar coronectomies. Clinical and radiographic evaluation of all patients were performed preoperatively and at 7, 90 and 365 days postoperatively. Sociodemographic, clinical and radiographic data were collected. The root migration was analyzed by the distance from the tooth apex to the mandibular canal, and radiographic bone density above the remaining roots was obtained, both using the software Image J©.Results: After 1-year follow-up no patients showed paresthesia, symptoms or required reintervention, however all roots showed migration. The mean root migration was 2.66 mm at 90 days, and 3.37 mm at 365 days (p = 0.0007). The rate of migration was higher at the early postoperative period. The simple linear regression test between root migration and radiographic bone density was not significant (R=-0.173 and p=0.453; R=-0.045 and p=0.902; at 90 days and 365 days, respectively) as well as the analysis between root migration and other clinical and radiographic variables. Conclusion: It was possible to conclude, based on these preliminary results, that all roots showed migration during the follow-up period. The radiographic bone density increases and, consequently, the root migration rate diminishes within time, however none of the evaluated factors showed significant association with root migration. (AU)

Objetivo: O objetivo deste estudo prospectivo, com resultados preliminaraes, foi avaliar os fatores relacionados com a migração das raízes após corocetomia de terceiros molares inferiores, especialmente a densidade óssea radiográfica. Material e Métodos: Vinte e dois pacientes foram submetidos à 31 coronectomias de terceiros molares inferiores. Avaliação clínica e radiográfica de todos os pacientes foi executada no momento pré-operatório e aos 7, 90 e 365 dias pós-operatórios. Dados sociodemográficos, clínicos and radiográficos foram coletados. A migração das raízes foi analisada pela distância do ápice radicular ao canal mandibular, e a densidade óssea radiográfica foi mensurada acima dos remanescentes radiculares, usando o software Image J©.Resultados: Após 1 ano de acompanhamento, nenhum paciente apresentou parestesia, sintomatologia ou necessitou reintervenção, porém todas as raízes migraram. A média da migração radicular foi de 2,66mm aos 90 dias e de 3,37mm aos 365 dias (p=0,0007). A taxa de migração foi maior no pós-operatório inicial. O teste de regressão linear simples entre migração das raízes e densidade óssea radiográfica não foi significante (R=-0,173 e p=0,453; R=-0,045 e p=0,902; aos 90 e 365 dias, respectivamanete), assim como a análise entre migration radicular e outras variáveis clínicas e radiográficas. Conclusão: Foi possível concluir, com base nesses resultados prelimiares, que todas as raízes apresetaram migração durante o período de acomapanhamento. A densidade óssea radiográfica aumentou e, consequentemente, a taxa de migration radicular dimininiui com o tempo, porém nenhum dos fatores avaliados mostrou associação significante com a migração das raízes(AU)

Mandibular canal bifurcation and trifurcation: case report from a finding obtained through cone beam computed tomography / Bifurcação e trifurcação do canal mandibular: relato de caso a partir de um achado em tomografia computadorizada de feixe de cone

Aim: This case report aims to demonstrate a rare mandibular canal (MC) variation, presenting right trifurcation and left bifurcation through Cone-Beam Computed Tomography (CBCT). Case report: A 26-year-old female patient with no systemic disorders was referred for surgical removal of the lower third molars due to the presence of painful symptoms. CBCT was requested to evaluate the relationship between third molars and the mandibular canal and to guide the surgical planning. Tomographic volume was analyzed through the Sidexis software (Sirona Dental Systems, Bernsheim, Germany). During the analysis of tomographic sections, it was possible to observe the presence of bilateral MC variations. Bifurcation of the right MC and trifurcation of the left MC were observed. Conclusion: The present report highlighted the importance of CBCT for the diagnosis of anatomical changes, such as MC trifurcation.

Objetivo: Este relato tem por objetivo descrever uma rara variação do canal mandibular (CM) apresentando trifurcação direita e bifurcação esquerda, por meio da Tomografia Computadorizada de Feixe Cônico (TCFC). Relato do caso: Paciente do sexo feminino, 26 anos de idade, sem comprometimento sistêmico, foi encaminhada para remoção cirúrgica dos terceiros molares inferiores devido a presença de sintomatologia dolorosa. Foi solicitada uma TCFC para avaliar a relação entre terceiros molares e o canal mandibular, para orientar o planejamento cirúrgico. O volume tomográfico foi analisado por meio do software Sidexis (Sirona Dental Systems, Bernsheim, Alemanha). Durante a análise dos cortes tomográficos, foi possível observar a presença de variações do CM bilateralmente. Observou-se bifurcação do CM direito e trifurcação do CM esquerdo. Conclusão: O presente relato destacou a importância da TCFC para o diagnóstico das alterações anatômicas, como a trifurcação do canal mandibular.

Determinación de la morfología del canal incisivo mandibular mediante tomografía computarizada de haz cónico (CBCT) en población de Valdivia, Chile / Determination of mandibular incisor canal morphology by cone beam computed tomography (CBCT) in a population of Valdivia, Chile

RESUMEN: El canal incisivo mandibular (MIC) es un canal neural que contiene una de las ramas inferiores del nervio alveolar inferior, llamado nervio incisivo mandibular, que puede resultar dañado durante intervenciones quirúrgicas y causar complicaciones postoperatorias. Estudio descriptivo de corte transversal. Se identificó el MIC en la imagen transversal del canino en 83 hemiarcadas. Se registró edad, sexo, hemiarcada, longitudes desde reborde alveolar vestibular de canino a MIC, cortical lingual y vestibular de canino a MIC, base mandibular de canino a MIC y ubicación del MIC (tercio lingual, medio, vestibular). Medidas se registraron en milímetros. Se aplicó test T-student para muestras independientes para variables de longitud y Chi-cuadrado para ubicación espacial del MIC, en relación con grupo etario y sexo. Se evaluó el MIC en todas las muestras (100 %). El MIC fue encontrado mayormente en el tercio medio mandibular (p <0,05). La media desde el MIC a la cortical lingual es de 5,25 mm ? 1,42 mm (derecho) y 5,24 mm ? 1,18 mm (izquierdo). La media desde el MIC a la cortical vestibular fue de 4,42 mm ? 1,29 mm (derecho) y 4,53 mm ? 1,24mm (izquierdo). La media entre centro del canal y reborde alveolar vestibular fue 18,89 mm ? 2,68mm (derecho) y 18,20 mm ? 3,06 mm (izquierdo), media desde centro del MIC al margen basal fue de 9,77 mm ? 1,93 (derecho) y 10,12 mm ? 1,92 mm (izquierdo). Se encontró mayor distribución del MIC en el tercio medio mandibular. Se identificó el MIC en el 100 % de las muestras a través de CBCT por lo que su uso como examen complementario debe ser considerado al planificar cirugías en el sector anterior mandibular.

SUMMARY: The objective of the study was to determine the morphology of the mandibular incisive canal (MIC) and its location using cone beam computed tomography (CBCT) in the population of Valdivia, Chile. Descriptive cross-sectional study. MIC was identified in the canine cross image in 83 quadrants. Age, gender, quadrants, length from buccal alveolar ridge of canine to MIC, lingual and buccal cortical of canine to MIC, mandibular base of canine to MIC, and location of MIC (lingual, middle and buccal third) were recorded. Measurements were recorded in millimeters. Independent sample Student-T test was performed to determine length variables and Chi-square test was performed to determine spatial location of MIC, in relation to age group and gender. MIC was evaluated in all samples (100 %). MIC was found mainly in the mandibular third quadrant (p < 0.05). The mean from the MIC to the lingual cortex is 5.25 mm ? 1.42 mm (right) and 5.24 mm ? 1.18 mm (left). The mean from the MIC to the buccal cortex was 4.42 ? 1.29 mm (right) and 4.53 mm ? 1.24 mm (left). The mean between the center of the canal and the buccal alveolar ridge was 18.89 mm ? 2.68mm (right) and 18.20 mm ? 3.06 mm (left), the mean from the center of the MIC to the basal edge was 9.77 mm ? 1.93 (right) and 10.12 mm ? 1.92 mm (left). A greater distribution of MIC was found in the mandibular third quadrant. MIC was identified in 100 % of the samples through CBCT, therefore, its use as a complementary examination should be considered when planning surgeries in the anterior mandibular area.

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.

Trigeminal nerve injuries. Four years' experience at a single Argentine referral center and a literature review / Lesiones del nervio trigémino. Cuatro años de experiencia de un servicio quirúrgico odontológico en Argentina y revisión bibliográfica

ABSTRACT The aim of this retrospective study was to describe the etiology and characteristics of trigeminal nerve injuries referred to a specialized center in Buenos Aires, Argentina. A retrospective analysis was performed of patients referred from February 2016 to January 2020. Age, sex, intervention performed, nerve affected, time elapsed from injury, diagnosis, location, and whether patient had signed informed consent were recorded. A descriptive analysis of the data was made, and 95% confidence intervals were calculated for prevalence. The study sample consisted of 30 subjects (31 nerve injuries), 19 female and 11 male, average age (±SD) 40 ± 17 years. The inferior alveolar nerve was the most frequently injured nerve (74%,) while the lingual nerve accounted for 26%. The most common etiologies were inferior molar extractions (47%), dental implants (20%), and local anesthesia (13%). Other etiologies were autologous mandibular bone grafts for dental implants, removal of cysts associated with the inferior third molar, and endodontic treatment. Dental Institutions at which treatment was provided were found to be significantly associated with patients being warned and asked to sign informed consent (p<0.05), while dentists working at private offices requested fewer consents. The most frequent symptom was paresthesia, and 5 patients suffered spontaneous or evoked pain. Only 2 patients intended to file legal claims. Dentists should be aware of the debilitating effects resulting from trigeminal injuries, the complexity of their resolution and the importance of carefully planning dental procedures to prevent them.

RESUMEN El objetivo de este estudio fue describir la etiología y características de las lesiones del nervio trigémino remitidas a un servicio de referencia especializado en Buenos Aires, Argentina. Se realizó un análisis retrospectivo de los pacientes remitidos desde febrero de 2016 a enero de 2020. Se registraron edad, género, intervención recibida, nervio afectado, tiempo transcurrido desde la lesión, diagnóstico, ubicación y firma del consentimiento informado previo a la intervención Se realizó un análisis descriptivo de los datos y se calcularon intervalos de confianza del 95%. La muestra del estudio consistió en 30 sujetos (31 lesiones nerviosas), 19 mujeres y 11 hombres, con una edad promedio (± DE) de 40 ± 17 años. Aproximadamente 3 de cada 4 lesiones correspondieron al nervio alveolar inferior, representando el resto al nervio lingual. Las etiologías más frecuentes fueron la extracción dentaria (47%), los implantes dentales (20%) y la aplicación anestesia local (13%). Otras etiologías fueron la regeneración ósea para la colocación de implantes mandibulares, la extirpación de quistes asociados al tercer molar inferior y el tratamiento endodóntico. Se encontró que el tipo de establecimiento donde se realizó el procedimiento odontológico que generó la lesión, se asoció significativamente con los pacientes a los que se les advirtió y se les pidió que firmen el consentimiento informado (p<0.05); los odontólogos que trabajan en consultorios privados obtienen una menor proporción de consentimientos que los de las instituciones. El síntoma más frecuente fue la parestesia y 5 pacientes sufrieron dolor espontáneo o evocado. Solo 2 pacientes tenían intención de iniciar acciones legales. Teniendo en cuenta que son lesiones potencialmente permanentes, y de resolución compleja, la comunidad odontológica debe realizar especiales esfuerzos para disminuir esta complicación.

Coronectomia: alternativa à exodontia de terceiros molares inferiores / Coronectomy: an alternative to third lower molar extraction

Objetivo: relatar um caso clínico de coronectomia com acompanhamento pós-operatório de 15 meses. Relatode caso: a coronectomia é uma alternativa de tratamento para terceiros molares inferiores (3MI) impactadosque apresentam proximidade com o canal mandibular, minimizando o risco de morbidade neurossensorial.A técnica consiste em remover apenas a coroa dentária (na junção amelocementária) com retençãointencional das raízes e da polpa, evitando o dano direto ou indireto ao nervo alveolar inferior (NAI). Oprocedimento foi realizado em paciente adulto do gênero masculino com 3MI impactados. A radiografia panorâmicamostrava o escurecimento dos ápices radiculares, sugerindo íntima relação das raízes com o canalmandibular. No acompanhamento pós-operatório imediato, o paciente retornou sem sintomatologia dolorosa,sem edema facial significativo, apresentando boa cicatrização e sem relato de perda de sensibilidade nemde disfunção mastigatória. No acompanhamento radiográfico, foi verificada neoformação óssea adjacenteaos remanescentes radiculares. Considerações finais: a coronectomia mostrou-se um procedimento simples,eficaz e seguro para diminuir o risco de injúria ao NAI durante o tratamento dos 3MI.(AU)

Objective: to report a case of coronectomy with follow-up of 15 months. Case report: coronectomy is an alternative treatment for impacted lower third molars (3ML) which are close to the mandibular canal, minimizing the risk of sensorineural morbidity. The technique consists of removing only the dental crown (at the cementoenamel junction) with intentional retention of the roots and pulp, avoiding direct or indirect damage to the inferior alveolar nerve (IAN). The procedure was performed on an adult male patient with impacted 3ML. Panoramic radiograph showed darkening of the roots, suggesting a close relationship between the roots and the mandibular canal. At immediate postoperative follow-up, the patient returned with no painful symptoms, no significant facial edema, good healing, and no loss of sensation or masticatory dysfunction. Radiographic follow-up showed bone neoformation adjacent to the root remnants. Final considerations: coronectomy has been shown to be a simple, effective and safe procedure to decrease the risk of injury to IAN during 3MI treatment.(AU)

Odontectomia parcial intecional: relato de caso clínico / Intentional partial odontectomy: a case report

Introdução: A Odontectomia Parcial Intencional ou Coronectomia é uma abordagem cirúrgica que consiste na remoção da porção coronária de molares mandibulares impactados e a manutenção das suas raízes no alvéolo dentário. Esta técnica é indicada quando há íntima relação entre o dente e o canal mandibular e tem por principal objetivo evitar lesões ao nervo alveolar inferior. Relato de Caso: Paciente do sexo masculino, 24 anos, ASA I, compareceu a Clínica Escola de Cirurgia de uma universidade pública para exodontia de terceiro molar inferior impactado (48). Ao exame clínico o dente apresentava-se semi-incluso e ao exame radiográfico (panorâmica e tomografia computadorizada), observou-se íntima relação da raiz do dente com o canal mandibular. Diante disto, foi realizada Odontectomia Parcial Intencional, com o intuito de preservação de feixe vásculo-nervoso adjacente. Paciente evoluiu satisfatoriamente sem sinais de infecção ou alteração sensorial de nervo alveolar inferior. Considerações finais: A Odontectomia Parcial Intencional é uma técnica segura, eficaz e de previsibilidade significativa, sendo uma alternativa que pode ser empregada em exodontias de molares mandibulares inclusos próximos ao canal mandibular, minimizando os riscos de lesões nervosas para os pacientes... (AU)

Introduction: Intentional partial odontectomy or coronectomy is a surgical approach that consists of removing the coronary portion of impacted mandibular molars and maintaining their roots in the dental alveolus. This technique is indicated when there is an intimate relationship between the tooth and the mandibular canal and its main objective is prevent injuries to the lower alveolar nerve. Case Report: Male patient, 24 years old, ASA I, compared the Clinical School of Surgery of a public university for extraction of the impacted lower third molar (48). On clinical or dental examination, we present semi impacted wisdom tooth and on radiographic examination (panoramic + computed tomography), an intimate relationship between the root of the tooth and the mandibular canal was observed. Therefore, intentional partial odontectomy was performed in order to preserve the adjacent vascular-nervous bundle. The patient progressed satisfactorily without signs of infection or sensory alteration of lower alveolar nerve. Final considerations: Intentional partial odontectomy is a safe, effective and predictable technique, being an alternative that can be used in extractions of mandibular molars, including those close to the mandibular canal, minimizing the risk of nerve injuries to patients... (AU)

Morphometric and Topographic Assessment of Foramen Ovale in Skulls of Jharkhand Population

Foramen ovale, situated in the greater wing of sphenoid, posterolateral to the foramen rotundum, transmits the sensory and motor root of mandibular nerve, accessory meningeal artery, emissary vein and lesser petrosal nerve to the infratemporal fossa. The normal shape of the foramen is oval, but its shape and size is quite variable. It plays an important role in the diagnostic and surgical procedures related to the middle cranial fossa. So, knowledge of the variations, dimensions and the topographic location is of importance to the neurosurgeons while dealing with surgeries in this region. Our study aims at finding the morphological variations in shape, dimensions of foramen ovale and its location in relation to the zygomatic arch.METHODSA cross-sectional observational study was carried out over a period of one year from 1/6/2018 to 31/5/2019, on 46 adult human skulls, taken from the department of Anatomy, RIMS, Ranchi. Fully dried, intact, adult human skulls were included in the study. Foramen ovale was observed for variation in shape, size and location. The presence of any accessory bony structure like bony plate, spine or septa was looked for and prevalence noted. The maximum antero-posterior length and width of foramen ovale and its distance from articular tubercle and the anterior root of zygomatic arch were measured using Vernier callipers. Pathologically malformed and damaged skulls were excluded from the study.RESULTSFour types of shapes were observed – oval (76.08%) , almond (5.43%) , semilunar (8.69%) and triangular (9.78%). The mean anteroposterior dimension of foramen ovale was 6.96 ± 1.17 mm (6.89 ± 1.28 mm on the right side & 7.02 ± 1.05 mm on the left side) and the mean transverse dimension was 3.35 ± 0.66 mm (3.25 ± 0.57 mm on the right side, 3.45 ± 0.73 mm on the left side) . The mean distance of foramen ovale from articular tubercle on zygomatic arch was 32.58 ± 1.29 mm (32.41 ± 1.10 mm on the right side, 32.74 ± 1.45 mm on the left side) and from anterior root of zygomatic arch was 24.75 ± 1.70 (23.91 ± 0.85 mm on the right side, 25.59 ± 1.92 mm on the left side).CONCLUSIONSThere is no significant average difference between FO_AP_RT – FO_AP_LT. There is no significant average difference between FO Width_RT - FO_Width_LT. There is a significant average difference between FO to Art. Tubercle Right - FO to Art Tubercle left. There is a significant average difference FO to ant. root Right - FO to ant. root left.

Outcomes after mandibular third molar coronectomy / Desfechos após coronectomia de terceiros molares inferiores

ABSTRACT Coronectomy is an alternative technique to mandibular third molar removal to avoid inferior alveolar nerve impairment. It is indicated in cases where the dental roots are in close relationship with the nerve which results in a higher risk of damage and paresthesia. The coronectomy technique is considered a safe method to prevent inferior alveolar nerve injury, however it shows particular postoperative outcomes as migration and exposure of the retained roots, and possibility of additional intervention. The aim of this case series is to describe four different outcomes from coronectomy, in patients treated by the same protocol. The outcomes ranged from asymptomatic to migration, infection and root removal. Although the variety of outcomes, none of the patients showed inferior alveolar nerve impairment. Therefore, the main objective of coronectomy was reached.

RESUMO A coronectomia é uma técnica alternativa à extração de terceiros molares inferiores para a prevenção de lesão ao nervo alveolar inferior. É indicada em casos em que as raízes dentárias estão em íntimo contato com o nervo alveolar, resultando em um maior risco de lesão, e consequentemente parestesia. A técnica de coronectomia é considerada um método seguro para prevenção de lesões ao nervo alveolar inferior, entretanto pode apresentar desfechos pós-operatórios singulares, incluindo a migração e exposição dos remanescentes radiculares, além da possibilidade de intervenções adicionais. O objetivo desta série de casos é descrever quatro desfechos diferentes da técnica de coronectomia, em pacientes tratados por meio de um único protocolo. Os desfechos pós-operatórios apresentados variaram entre casos assintomáticos até migração das raízes, infecção e necessidade de remoção do remanescente radicular. Entretanto, apesar da variedade de desfechos, nenhum dos pacientes apresentou lesão ao nervo alveolar inferior. Desta forma, conclui-se que o objetivo principal da técnica foi alcançado apesar dos diferentes desfechos.

Análise topográfica da relação de terceiros molares inferiores com os canais mandibulares através de tomografias computadorizadas / Topographic analysis of the relationship of lower third molars with the mandibular canal through computerized tomographies / Análisis topográfico de la relación de terceros molares inferiores con los canales mandibulares por medio de tomografías computadorizadas

Resumo Introdução e Objetivo: Os canais mandibulares são estruturas anatômicas que se estendem desde o forame mandibular até o forame mentoniano e em seu interior localizam-se o nervo, artéria e veia alveolar inferior. Verificar a topografia anatômica de terceiros molares em relação aos seus respectivos canais mandibulares através de Tomografias Computadorizadas de um banco de dados. Materiais e métodos: Exames de 48 pacientes com terceiros molares bilaterais foram obtidos por um aparelho de Tomografia Computadorizada Helicoidal Multislice, General Eletric® do banco de dados de uma clínica privada de Teresina-PI e analisados. Resultados: Para os terceiros molares inclusos, a distância nula em relação ao canal mandibular foi a mais prevalente (59,68%), enquanto que a posição das raízes apresentou-se na maioria dos casos superior (53,13%) e vestibular (45,3%) em relação ao canal mandibular. Este se encontrava geralmente próximo à cortical lingual (79,17%). Conclusão: Houve maior prevalência de distância nula dos ápices radiculares ao canal quando os terceiros molares encontravam-se inclusos (maioria mesioangulados) e, superior ao canal quando estavam erupcionados. No sentido vertical, os ápices radiculares encontravam-se mais frequentemente na posição superior ao canal. Já no aspecto horizontal, os ápices radiculares estavam mais vestibulares ao canal mandibular. E este se encontrava frequentemente próximo à cortical lingual.

Abstract Introduction and objective: The mandibular canals are anatomical structures that extend from the mandibular foramen to the mental foramen, and the interior of the mandibular canal is located the nerve, artery and inferior alveolar vein. To verify the anatomical topography of third molars in relation to their respective mandibular channels through Computerized Tomography of a database. Materials and methods: 48 patients with bilateral third molars were obtained by a Helicoidal Multislice Computed Tomography, General Eletric® from the database of a private clinic in Teresina-PI and analyzed. Results: For the third molars included, the null distance in relation to the mandibular canal was the most prevalent (59.68%), while the position of the roots presented in most cases superior (53.13%) and vestibular (45.3%) in relation to the mandibular canal. This was generally close to the lingual cortical (79.17%). Conclusion: There was a higher prevalence of null distance from the root apexes to the canal when third molars were included (most mesioangulated) and superior to the canal when they were erupted. In the vertical direction, the root apexes were more often in the position superior to the canal. In the horizontal aspect, the root apices were more vestibular to the mandibular canal. And this was often close to the lingual cortical.

Resumen Introducción y Objetivo: Los canales mandibulares son estructuras anatómicas que se extienden desde el foramen mandibular hasta el foramen mentoniano y en su interior se encuentra el nervio, arteria y vena alveolar inferior. Verificar la topografía anatómica de terceros molares con relación a sus respectivos canales mandibulares por medio de Tomografías Computadorizadas de un banco de datos. Materiales y métodos: Exámenes de 48 pacientes con terceros molares biltaerales fueron obtenidos y analizados por un tomógrafo Helicoidal Multislice, General Electric® del banco de datos una clínica particular de Teresina-PI. Resultados: Para los terceros molares incluidos, la distancia nula con relación al canal mandibular fue la más prevalente (59,68&), mientras que la posición de las raíces se presentó en la mayoría de los casos superior (53,13%) y vestibular (45,3%) con relación al canal mandibular. Este se encontraba generalmente próximo a la cortical lingual (79,17%). Conclusión: Hubo mayor prevalencia de distancia nula de los ápices radiculares al canal cuando los terceros molares estaban incluidos (mayoría mesioangulados) y superior al canal cuando estaban erupcionados. En el sentido vertical, los ápices radiculares se encontraron frecuentemente superior al canal. En el sentido horizontal, los ápices radiculares estaban más vestibulares al canal mandibular. Este se encontraba próximo a la cortical lingual.

Prevalencia y factores asociados a las lesiones en los nervios alveolar inferior y lingual después de la exodoncia de terceros molares inferiores: Estudio retrospectivo / Prevalence and associated factors of inferior alveolar and lingual nerves injuries after lower third molars extractions: Retrospective study / Prevalência e fatores associados às lesões nos nervos alveolar inferior e lingual após a exodontia de terceiros molares inferiores: Estudo retrospectivo

Dentro de los tratamientos realizados en cirugía oral, la extracción de los terceros molares es la más frecuente y puede ocasionar lesiones nerviosas. Objetivo: Determinar la prevalencia y los factores asociados a las lesiones en los nervios alveolar inferior y lingual después de la extracción de terceros molares inferiores. Materiales y métodos: la muestra fue de 609 prontuarios analizados durante los años 2011-2016 en el Hospital Carlos Andrade Marín de la ciudad de Quito, Ecuador. Fueron consideradas como variables: sexo, edad, posición y profundidad del tercer molar (Pell y Gregory), la inclinación (Winter) y la relación radiográfica con el canal mandibular (Rood y Shehab). Los datos obtenidos fueron pro-cesados utilizando la prueba estadística de Chi-cuadrado con un nivel de significancia de 5%. Resultados: Presentaron lesiones nerviosas el 2,46% de los pacientes atendidos, correspondiendo al 1,64% y 0,82% a los nervios alveolar inferior y lingual respectivamente. La lesión del nervio alveolar inferior está asociado al sexo femenino (p= 0.032) y con la clase III (p= 0.010), mientras que las lesiones del nervio lingual estaban asociadas a la clase I (p= 0.004) y tipo A (p= 0.001). Radio-gráficamente la lesión del nervio alveolar está asociada en el 46,67% con la interrupción de la línea del canal mandibular (p= 0.010). Conclusión: La prevalencia de las lesiones en los nervios alveolar inferior y lingual posterior a la exodoncia del tercer molar inferior en pacientes ecuatorianos es baja, cuidados preoperatorios son importantes para evitar complicaciones postquirúrgicas.

Among the treatments performed in oral surgery, the third molars extraction is the most frequent and may cause nerve in-juries. Objective: To determine the prevalence and associated factors of inferior alveolar and lingual nerves injuries after inferior third molars extractions. Materials and methods: the sample was composed by of 609 records attended during the years 2011-2016 in the Carlos Andrade Marín Hospital in the city of Quito, Ecuador. The following variables were as-sessed: sex, age, position and depth of the third molar (Pell & Gregory), inclination (Winter) and radiographic relationship with the mandibular canal (Rood & Shehab). Data obtained were processed througth the Chi-square test with a significance level of 5%. Results: of all patients attended, 2.46% presented nerves injuries, corresponding to 1.64% and 0.82% to the inferior alveolar and lingual nerves respectively. The inferior alveolar nerve injury is associated with the female sex (p = 0.032) and with the class III (p = 0.010), while the lingual nerve lesions were associated with class I (p = 0.004) and type A (p = 0.001). Radiographically, the alveolar nerve injury is associated in 46.67% with the interruption of the mandibular canal line (p = 0.010). Conclusion: The prevalence of injuries in the inferior alveolar and lingual nerves after lower third molar extractions in Ecuadorian patients is low; preoperative care is important to avoid postoperative complications.

Dentre os tratamentos realizados na cirurgia bucal, a extração dos terceiros molares é a mais frequente e pode causar lesões nervosas. Objetivo: Determinar a prevalência e os fatores associados às lesões nos nervos alveolar inferior e lingual após a extração de terceiros molares inferiores. Materiais e métodos: a amostra foi de 609 prontuários analisados durante os anos de 2011 a 2016 no Hospital Carlos Andrade Marín, na cidade de Quito, Equador. Foram consideradas as seguintes variáveis: sexo, idade, posição e profundidade do terceiro molar (Pell e Gregory), inclinação (Winter) e relação radiográfica com o canal mandibular (Rood e Shehab). Os dados obtidos foram processados pelo teste estatístico Qui-quadrado com nível de significância de 5%. Resultados: Apresentaram lesões nervosas 2,46% dos pacientes atendidos, correspondendo a 1,64% e 0,82% dos nervos alveolar inferior e lingual respectivamente. A lesão do nervo alveolar inferior está associada ao sexo feminino (p = 0.032) e à classe III (p = 0.010), enquanto as lesões do nervo lingual foram associadas à classe I (p = 0.004) e tipo A (p = 0.001). Radiograficamente, a lesão do nervo alveolar está associada em 46,67% com a interrupção da linha do canal mandibular (p = 0.010). Conclusão: A prevalência de lesões nos nervos alveolar inferior e lingual após a extração do terceiro molar inferior em pacientes equatorianos é baixa; cuidados pré-operatórios são importantes para evitar complicações pós-operatórias.

Prognosis in case of nerve disturbance after mandibular implant surgery in relation to computed tomography findings and symptoms

PURPOSE: The aim of this study was to evaluate the computed tomography (CT) imaging findings and clinical symptoms of patients who complained of neurosensory disturbances after mandibular implant surgery, and to investigate the relationships of these parameters with the prognosis for recovery. METHODS: CT scans were reviewed in 56 patients with nerve disturbance after mandibular implant surgery. Two oral radiologists classified the imaging findings into intrusion, contact, close, and separate groups according to the distance from the inferior border of the implant to the roof of the mandibular canal (MC). The symptoms of 56 patients were classified into 8 groups and the frequency of each group was investigated. Patients were categorized according to symptom improvement into no recovery and recovery groups, and the relationships of recovery with the CT classification and specific symptom groups were analyzed. RESULTS: Thirty-eight of the 56 nerve disturbance cases showed improvement. The close and separate groups in the CT classification had a strong tendency for recovery (90.9% and 81.8%, respectively) (P<0.05). Although the lowest recovery rate was found in the intrusion group, it was non-negligible, at 50%. The 6 patients with a worm crawling feeling all improved, while the 8 cases with a tightening sensation showed the lowest recovery rate, at 12.5%, and the symptom of a tightening sensation occurred only in the intrusion and contact groups. CONCLUSIONS: The closer the implant fixture was to the MC on CT images, the less likely the patient was to recover. Regarding paresthesia symptoms, while a worm crawling feeling is thought to be a predictor of recovery, a tightening sensation appeared to be associated with a lower recovery rate.

Diversion of the mandibular canal: Is it the best predictor of inferior alveolar nerve damage during mandibular third molar surgery on panoramic radiographs?

PURPOSE: The aim of this study was to evaluate the relationship between the mandibular canal and impacted mandibular third molars using cone-beam computed tomography (CBCT) and to compare the CBCT findings with signs on panoramic radiographs (PRs). MATERIALS AND METHODS: This retrospective study consisted of 200 mandibular third molars from 200 patients who showed a close relationship between the mandibular canal and impacted third molars on PRs and were referred for a CBCT examination of the position of the mandibular canal. The sample consisted of 124 females and 76 males, with ages ranging from 18 to 47 years (mean, 25.75±6.15 years). PRs were evaluated for interruption of the mandibular canal wall, darkening of the roots, diversion of the mandibular canal, and narrowing of the mandibular canal. Correlations between the PR and CBCT findings were statistically analyzed. RESULTS: In total, 146 cases (73%) showed an absence of canal cortication between the mandibular canal and impacted third molar on CBCT images. A statistically significant relationship was found between CBCT and PR findings (P<0.05). The absence of canal cortication on CBCT images was most frequently accompanied by the PR sign of diversion of the mandibular canal (96%) and least frequently by interruption of the mandibular canal wall (65%). CONCLUSION: CBCT examinations are highly recommended when diversion of the mandibular canal is observed on PR images to reduce the risk of mandibular nerve injury, and this sign appears to be more relevant than other PR signs.