الملخص
SUMMARY: Anterior loop in the mental foramen region is a critical region in the mandible. The non detection of anterior loop leads to inadvertent complications during the surgical procedures in this region. This study aimed to evaluate the morphological assessment of the mental foramen's anterior loop (AL) using (CBCT) cone-beam computed tomography. CBCT data was retrieved from January 2018 to December 2022 and screened for eligibility. Images were viewed using panoramic reconstructed views for initial screening. Further multiplanar reformatted view in axial, coronal and sagittal planes were examined. When anterior loop was detected, the path of inferior alveolar canal was traced and the anterior loop was analyzed. Statistical analysis was carried out on the data. Cross-tabulation was done to associate gender and age with the achieved findings (heights and diameters) using the Chi-square test. In this analysis 519 cases were included and examined for presence of anterior loop. 22 cases were included in the study, out of which 10(45.5%) males and 12(54.5%) females. The prevalence of AL is high among females. AL was found higher on the right side in 14 (68.2%) cases compared to the left side with 7 (31.8%) cases. The mean diameter of AL on the right side was 2.5 mm, and on the left side diameter was 1.96 mm. The prevalence of anterior loop in the region of mental foramen in Saudi Population was found to be 4.24%. Careful evaluation for the anterior loop can prevent hemorrhagic episodes during surgical intervention or implant procedures in the mandibular premolar region.
El asa anterior en la región del foramen mentoniano es una región crítica en la mandíbula. La no detección del asa anterior conduce a complicaciones inadvertidas durante los procedimientos quirúrgicos en esta región. Este estudio tuvo como objetivo evaluar la evaluación morfológica del asa anterior (AL) del foramen mental mediante tomografía computarizada de haz cónico (CBCT). Los datos CBCT se recuperaron desde enero de 2018 hasta diciembre de 2022 y se examinaron para determinar su elegibilidad. Las imágenes se visualizaron utilizando vistas panorámicas reconstruidas para la evaluación inicial. Se examinaron además, vistas reformateadas multiplanares en los planos axial, coronal y sagital. Cuando se detectó el asa anterior, se trazó el trayecto del canal mandibular y se analizó el asa anterior. Se realizó un análisis estadístico de los datos. Mediante la prueba de Chi-cuadrado se realizó una tabulación cruzada para asociar el sexo y la edad con los hallazgos obtenidos (alturas y diámetros). En este análisis se incluyeron y examinaron 519 casos para detectar la presencia de asa anterior. Se incluyeron en el estudio 22 casos, de los cuales 10 (45,5 %) eran hombres y 12 (54,5 %) mujeres. La prevalencia de AL es alta entre las mujeres. Se observó que AL fue mayor en el lado derecho en 14 (68,2 %) de los casos en comparación con el lado izquierdo con 7 (31,8 %) casos. El diámetro medio de AL en el lado derecho fue de 2,5 mm y en el lado izquierdo fue de 1,96 mm. La prevalencia del asa anterior en la región del foramen mental en la población saudí fue de 4,24 %. Una evaluación rigurosa del asa anterior puede prevenir episodios hemorrágicos durante una intervención quirúrgica o procedimientos de implante en la región de los premolares mandibulares.
الموضوعات
Humans , Male , Female , Adolescent , Adult , Middle Aged , Young Adult , Cone-Beam Computed Tomography , Mental Foramen/anatomy & histology , Mental Foramen/diagnostic imaging , Cross-Sectional Studies , Retrospective Studies , Sex Characteristics , Mandible/anatomy & histology , Mandible/diagnostic imagingالملخص
SUMMARY: Binge drinking in adolescents has a negative effect on the developing skeleton and the attainment of peak bone mass. Our study aimed to examine the effect of binge drinking on the growth and functional integrity of the adolescent Sprague Dawley rat mandible and to determine if a dosage of 1.5 g/kg is sufficient to produce a binge-model of consumption. A total of eight 7-week-old adolescent (male) Sprague Dawley rats were randomly placed into 4 groups with two rats each: 1-week alcohol-exposed rats, 1-week pair- fed control rats, 4-week alcohol-exposed rats and 4-week pair-fed control rats. The alcohol exposed groups were administered a single daily dose via oral gavage of 1.5 g/kg of 20 % alcohol 3 days a week (alternate days) for 7 or 28 days. The pair-fed control groups were administered a caloric equivalent dose of maltose dextrin via oral gavage on the same days as the alcohol-exposed rats. The one-week alcohol exposed, and control rats were terminated on day 7 and the four-week alcohol exposed and control rats on day 28. The mandibles were dissected out and osteometric measurements determined using a digital vernier caliper. Bones were scanned using a 3D-microCT scanner (Nikon XTH 255L). Biomechanical tests were done using a Shimadzu universal testing machine. Differences observed were regarding mandibular osteometry, which showed a reduced height in the central portion of the alveolar bone (Al'-Me), and an increase in the height of the condylar head (Cd-Ag) in the 1-week alcohol-exposed rats when compared to the 1-week pair-fed control rats. No other differences were noted. Lack of significant changes seen between the alcohol and pair-fed control groups in both acute binge and chronic binge exposed rats is likely due to the low dose of alcohol administered to the rats in the study thus a higher dose is proposed.
El consumo excesivo de alcohol en adolescentes tiene un efecto negativo en el desarrollo del esqueleto y en la consecución de la masa ósea máxima. Nuestro estudio tuvo como objetivo examinar el efecto del consumo excesivo de alcohol sobre el crecimiento y la integridad funcional de la mandíbula de la rata adolescente Sprague Dawley y determinar si una dosis de 1,5 g/kg es suficiente para producir un modelo de consumo compulsivo. Un total de ocho ratas Sprague Dawley adolescentes (machos) de 7 semanas de edad se colocaron aleatoriamente en 4 grupos con dos ratas cada uno: ratas expuestas al alcohol durante 1 semana, ratas de control alimentadas en parejas durante 1 semana, ratas expuestas al alcohol durante 4 semanas, y ratas de control alimentadas en parejas durante 4 semanas. A los grupos expuestos al alcohol se les administró una dosis única diaria mediante sonda oral de 1,5 g/kg de alcohol al 20 % 3 días a la semana (días alternos) durante 7 o 28 días. A los grupos de control alimentados por parejas se les administró una dosis calórica equivalente de maltosa dextrina mediante sonda oral los mismos días que a las ratas expuestas al alcohol. Las ratas expuestas al alcohol durante una semana, las ratas de control al día 7, las ratas expuestas al alcohol durante cuatro semanas y las ratas de control al día 28. Se diseccionaron las mandíbulas y se determinaron las mediciones osteométricas utilizando un calibre vernier digital. Los huesos se escanearon utilizando un escáner 3D-microCT (Nikon XTH 255L). Las pruebas biomecánicas se realizaron utilizando una máquina de pruebas universal Shimadzu. Las diferencias observadas se relacionaron con la osteometría mandibular, que mostró una altura reducida en la porción central del hueso alveolar (Al'-Me) y un aumento en la altura de la cabeza condilar (Cd-Ag) en las ratas expuestas al alcohol durante una semana, en comparación con las ratas control alimentadas en parejas durante una semana. No se observaron otras diferencias. La falta de diferencias significativas entre los grupos de alcohol y de control alimentados en parejas expuestas a ebriedad aguda y ebriedad crónica, probablemente se deba a la baja dosis de alcohol administrada a las ratas en el estudio, por lo que se propone una dosis más alta.
الملخص
Background: Denture adhesives are alternatives used to improve retention, stability, comfort and satisfaction in patients with complete dentures. Evidence on the effectiveness of denture adhesives on resorbed mandibular ridges is scarce. Among the many commercially available denture adhesives, the ideal material for the severely resorbed mandibular ridge remains in dispute. Objective: The aim of this study was to evaluate the effectiveness of different quantities of four commercially available denture adhesives on the retention of mandibular complete dentures in severely resorbed ridges. Materials and Methods: A resorbed edentulous mandibular ridge model was manufactured in acrylic resin. A denture base was made and three loops were attached to it. Four commercially available denture adhesives (Fixodent, Perlie White, Fiftydent and Polident) were tested in amounts of 0.2 g, 0.4 g, 0.6 g, 0.8 g and 1.0 g. The acrylic resin model was evenly moistened with 1 ml of water and a weighted amount of adhesive material was applied to the denture base. The universal testing machine engaged the loops fixed on the denture base and applied the vertical displacement force. The maximum vertical displacement force values were recorded for each denture adhesive material at different amounts. Statistical calculation was performed using Kruskal Wallis with Bonferroni post hoc correction. Results: Statistically significant differences were observed in the mean values of the vertical displacement force for adhesive amounts of 0.2 g, 0.4 g, 0.6 g and 1.0 g (p<0.05) between the four adhesive materials tested. Statistically significant differences were observed when four denture adhesives were compared to each other in different amounts (p<0.05). Statistically significant differences were observed between different amounts for each of four denture adhesives (p<0.05). Conclusions: Among the four materials tested, Polident showed greater effectiveness at 0.6 g and 0.8 g, Fittydent at 0.6 g, 0.8 g and 1 g, Fixodent at 0.4 g and 0.6 g and Perlie White at 1 g and 0.8g quantity to resist vertical displacement. forces on the severely resorbed mandibular crest. Using an appropriate amount of denture adhesive allows for proper retention of the denture; Replacement of this adhesive is necessary once a day.
Introducción: Los adhesivos para prótesis dentales son alternativas utilizadas para mejorar la retención, la estabilidad, la comodidad y la satisfacción en los pacientes con prótesis completas. La evidencia sobre la efectividad de los adhesivos para prótesis dentales en los rebordes mandibulares reabsorbidos es escasa. Entre los muchos adhesivos para prótesis dentales disponibles comercialmente, sigue estando en disputa cuál es el material ideal para el reborde mandibular severamente reabsorbido. Objetivo: El objetivo de este estudio fue evaluar la efectividad de diferentes cantidades de cuatro adhesivos para prótesis dentales disponibles comercialmente sobre la retención de prótesis dentales completas mandibulares en reborde mandibular reabsorbido severamente. Materiales y Métodos: Se fabricó un modelo de reborde mandibular edéntulo reabsorbido en resina acrílica. Se hizo una base para la prótesis y se le colocaron tres bucles. Se probaron cuatro adhesivos para dentaduras postizas disponibles comercialmente (Fixodent, Perlie White, Fiftydent y Polident) en cantidades de 0,2 g, 0,4 g, 0,6 g, 0,8 g y 1,0 g. El modelo de resina acrílica se humedeció uniformemente con 1 ml de agua y se aplicó la cantidad correspondiente de material adhesivo sobre la base de la dentadura. La máquina de prueba universal enganchó los bucles fijados en la base de la dentadura postiza y aplicó la fuerza de desplazamiento vertical. Se registraron los valores máximos de fuerza de desplazamiento vertical para cada material adhesivo para dentaduras postizas en diferentes cantidades. El cálculo estadístico se realizó utilizando Kruskal Wallis con corrección post hoc de Bonferroni. Resultado: Se observaron diferencias estadísticamente significativas en los valores medios de la fuerza de desplazamiento vertical para cantidades de 0,2 g, 0,4 g, 0,6 g y 1,0 g (p<0,05) entre los cuatro materiales adhesivos para prótesis dentales probados. Se observaron diferencias estadísticamente significativas cuando se compararon cuatro adhesivos para prótesis dentales entre sí en diferentes cantidades (p<0,05). Se observaron diferencias estadísticamente significativas entre diferentes cantidades en los cuatro adhesivos para prótesis (p<0,05). Conclusión: De los cuatro materiales probados, Polident mostró mayor efectividad a 0,6 g y 0,8 g, Fittydent a 0,6 g, 0,8 g y 1 g, Fixodent a 0,4 g y 0,6 g y Perlie White a 1 g y 0,8 g para resistir fuerzas de desplazamiento vertical en la cresta mandibular severamente reabsorbida. El uso de una cantidad adecuada de adhesivo para dentaduras postizas permite una retención adecuada de la dentadura postiza; El reemplazo de este adhesivo es necesario una vez al día.
الموضوعات
Humans , Adhesives/therapeutic use , Denture Retention/methods , Denture Design , Dental Prosthesis/methods , Models, Dental , Denture, Complete , Mandible/pathologyالملخص
SUMMARY: Mandibular incisive canal (MIC) and related mental foramen (MF) and anterior loop (AL) morphometrics are important landmarks in medical and dental clinical applications. The main aim of this retrospective study to determine the morphometry of the mandibular incisive canal (MIC) in a Jordanian population and to propose a new shape-pattern classification of the MIC. In addition, MF and AL morphometrics were determined. Carestream 3D imaging software was used on 100 Cone-Beam Computed Tomography (CBCT) of a Jordanian population to determine the MF, AL and MIC morphometrics. The detection prevalence of the MIC was 96 %. The right and left MIC showed four distinct line patterns, proposed for the first time in this paper. The line-patterns were angular (L-line), straight (I-line), curved (V-line) and wavy (W-line), with a prevalence of 41 %, 19 %, 25.5 %, and 10.5 %, respectively. MF was detected in all mandibles with a round shape in 58 % of the images. The most common horizontal and vertical positions of the MF were H4 and H3 (73.5 %) and V3 and V2 (95 %), respectively. An accessory MF was detected in 14.5 % of the samples and was more prevalent in males and on the right side. AL was detected in 92.5 % of the samples and exhibited a pattern prevalence of 25.5 %, 40 % and 27 % for types I, II and III, respectively. Results revealed that asymmetry and gender differences between right and left MIC, MF, AL and AMF was seen in patient's mandibles. In conclusion, this is the first study to propose and show that Mandibular incisive canal exhibits four potential line patterns (L, I, V and W lines patterns). Gender and ethnic variations of the mandibular canal landmarks morphometrics of both right and left hemi-mandible are important to be acknowledged in learning anatomy and when planning or performing dental and medical procedures.
Las relaciones de la morfometría del canal incisivo mandibular (MCI), del foramen mentoniano (FM) y del asa anterior (AA) son hitos importantes en las aplicaciones clínicas médicas y dentales. El objetivo principal de este estudio retrospectivo fue determinar la morfometría del MCI en una población jordana y proponer una nueva clasificación de patrón de forma del MCI. Además, se determinaron la morfometría de FM y AA. Se utilizó el software de imágenes 3D Carestream en 100 tomografías computarizadas de haz cónico (CBCT) de una población jordana para determinar la morfometría de FM, MCI y AA. La prevalencia de detección de MCI fue del 96 %. El MCI derecho e izquierdo mostraron cuatro patrones de líneas distintas, propuestas por primera vez en este artículo. Los patrones de líneas fueron angulares (línea L), rectos (línea I), curvos (línea V) y ondulados (línea W), con una prevalencia del 41 %, 19 %, 25,5 % y 10,5 % respectivamente. Se detectó el FM en todas las mandíbulas y con forma redonda en el 58 % de las imágenes. Las posiciones horizontal y vertical más comunes del FM fueron H4 y H3 (73,5 %) y V3 y V2 (95 %), respectivamente. Se detectó FM accesorio en el 14,5 % de las muestras y fue más prevalente en el sexo masculino y en el lado derecho. AA se detectó en el 92,5 % de las muestras y exhibió un patrón de prevalencia del 25,5 %, 40 % y 27 % para los tipos I, II y III, respectivamente. Los resultados revelaron asimetría y diferencias en el sexo entre MCI, FM, AA derecha e izquierda en las mandíbulas de los pacientes. En conclusión, este es el primer estudio que propone y muestra que el canal incisivo mandibular exhibe cuatro patrones de líneas potenciales (patrones de líneas L, I, V y W). Es importante reconocer las variaciones étnicas y de sexo de la morfometría de los puntos de referencia del canal mandibular de la hemimandíbula derecha e izquierda al estudiar y aprender anatomía y al planificar o realizar procedimientos médicos y dentales.
الموضوعات
Humans , Female , Adult , Middle Aged , Aged , Cone-Beam Computed Tomography , Mandible/anatomy & histology , Mandible/diagnostic imaging , Retrospective Studies , Mental Foramen/anatomy & histology , Mental Foramen/diagnostic imagingالملخص
Several variables can influence the treatment and outcome of orthognathic surgery, one of which is the angle of the mandibular ramus. The objective of this study is to analyze the upper airways (UA) of patients prior to orthognathic surgery, using cone-beam computed tomography (CBCT) and to correlate their volume with the angle of the mandibular ramus. DICOM (Digital Image Communication in Medicine) images of a radiology clinic were used, with a survey of 124 full face CBCT scans, from 2015 to 2018, and the measurement of the total volume in mm³ through software. To obtain the values of the angle of the mandibular ramus, images obtained from medical reports were used, through morphological evaluation. The values were tabulated and subsequently statistical analysis was performed using the ANOVA test to assess the differences between the mean airway volumes (mm³) according to gender, age and mandibular ramus angle. However, the angle of the ramus did not influence the volume of the UA, but a greater average of UA volume was observed in male individuals and in individuals over 34 years of age. There is no evidence that it is possible to measure or predict the volume of the UA by evaluating the angle of the mandibular ramus. (AU)
Diversas as variáveis podem influenciar no tratamento e resultado de uma cirurgia ortognática, uma delas é o ângulo do ramo mandibular. O objetivo deste trabalho é analisar as vias aéreas superiores (VAS) de pacientes previamente à cirurgia ortognática, por meio de tomografia computadorizada de feixe cônico (TCFC) e correlacionar o seu volume com o ângulo do ramo mandibular. Foram utilizadas imagens DICOM (Comunicação de Imagens Digitais em Medicina) de uma clínica radiológica, com o levantamento de 124 exames de TCFC de face total, do ano de 2015 até 2018 e feita a mensuração do volume total em mm³ através de um software. Para a obtenção dos valores do ângulo do ramo mandibular foram utilizadas imagens obtidas através dos laudos médicos, mediante avaliação morfológica. Os valores foram tabulados e posteriormente feita a análise estatística com o teste ANOVA para avaliar as diferenças entre as médias de volume das vias aéreas (mm³) de acordo com o gênero, a idade e o ângulo do ramo mandibular. Contudo, o ângulo do ramo não influenciou no volume das VAS, mas uma maior média de volume de VAS foi observada nos indivíduos do gênero masculino e nos indivíduos acima de 34 anos. Não há evidências de que se é possível mensurar ou ter previsibilidade do volume de VAS, avaliando o ângulo do ramo mandibular. (AU)
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Objective@#To investigate the clinical features, diagnosis and treatment of congenital epulis, to provide a reference for clinical diagnosis and treatment.@*Methods@#Two cases of congenital epulis in the mandible and maxilla of a newborn were reported, and the boundary and size of the tumor were determined by ultrasonography and MRI. The tumor was resected under general anesthesia. The previous literature on congenital epulis was reviewed and analyzed.@*Results@#Patient 1 (male) had a hard mass of approximately 20 mm × 15 mm × 10 mm in the right mandible immediately after birth. MRI was performed, and the mass was removed. In Patient 2 (female), a mass approximately 24 mm × 23 mm × 20 mm in the oral cavity of the anterior maxillary region was shown on ultrasound at 29 gestational weeks, and the mass grew rapidly in the last trimester. The mass was removed after birth. Postoperative pathological examination revealed congenital epulis. The results of the literature review showed that the incidence of congenital epulis is greater in females than in males, and it mainly occurs in the maxillary incisor area. Congenital epulis does not invade bone and does not affect tooth development. When a mass affects a child's breathing or swallowing, it must be surgically removed in a timely manner. Recent studies have shown that there is no evidence of recurrence after surgical resection. The histological origin and etiology of the disease are not clear. Clinically, it is often necessary to distinguish between teratomas and congenital epulis. Regarding the clinical manifestations, teratomas and congenital epulis are similar in appearance, and the main distinguishing point lies in pathological manifestations. Under the microscope, teratomas are observed as mature or immature tissue from various embryonic layers, while congenital epulis involves tightly arranged, homogeneous, polygonal to microspindle-shaped, medium to large cell compositions of nest-like and ribbon-like cells.@*Conclusion@#Congenital epulis is a rare oral tumor in neonates. The diagnosis should be based on the location, age, clinical manifestations, and imaging findings. The final diagnosis depends on pathological examination. When congenital epulis tumors affect children's breathing and eating, they should be surgically removed as soon as possible, and there is almost no recurrence after surgery.
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Objective@#To discuss the possible etiology, pathogenesis, clinical features, diagnosis and treatment of epidermoid cysts of the jaw and to provide a reference for clinical diagnosis and treatment.@*Methods@#A case of an epidermoid cyst in the right mandible with retained deciduous teeth and succedaneous impacted teeth was reviewed and analyzed in combination with the relevant literature.@*Results@#A patient presented with a mass in the right mandible that had persisted for 1 month after being found at imaging examination. Tooth 83 was retained, and tooth 43 was unerupted. Swelling was characterized by no obvious tenderness, fluctuation, or table tennis sensation and was observed in the lingual alveoli of teeth 83, 44, and 45. Imaging revealed a low-density shadow in the apex of teeth 83, 44, 45, and 46, approximately 1.9 cm × 2.6 cm × 1.6 cm in size, which wrapped around the dental crown of tooth 43. Preliminary diagnoses were as follows: right mandibular mass thought to be a dentigerous cyst; impacted tooth 43; and retained primary tooth 83. The mass in the right mandible was removed, and teeth 43 and 83 were extracted under intravenous and inhalation anesthesia. During the operation, the mass was observed to have a thin cyst wall and contained bean-like residue. Histopathological examination indicated an epidermoid cyst in the right mandible. At the 1-week follow-up examination, the patient reported no discomfort, and the surgical area showed good recovery. According to the literature, epidermoid cysts are benign cysts originating from ectopic ectodermal tissue that can occur throughout the body but rarely in the oral cavity and are even extremely rarer in the jaw. Epidermoid cysts of the jaw, which have no specific clinical manifestations, can be confused with odontogenic cysts such as dentigerous cysts and odontogenic tumors. Dental pulp tests and other techniques can serve as a reference for clinicians. The diagnosis is confirmed via histopathology. Surgical removal is a common treatment, with a good prognosis and a low recurrence rate.@*Conclusion@#The principle of treatment for an epidermoid cyst of the jaw is similar to that for a jaw cyst. The prognosis is good when the cyst is removed completely.
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Objective@#To explore the effect of different miniscrew placement heights on the distribution of biological forces produced by clear aligner combined with intramaxillary traction for mandibular molar distalization, to identify the miniscrew location that is conducive to the protection of lower anterior tooth anchorage and to provide a reference that can be used when designing clinical treatments.@*Methods@#Mimics, GeomagicStudio 2017, SolidWorks 2016, and Ansys workbench were used to establish finite element analysis models and perform mechanical analysis under the following six working conditions: working condition 1 was the control group without miniscrews; working conditions 2 to 5 had miniscrew in the buccal bone cortex between the first and second molars of the lower jaw 10 mm, 7 mm, 4 mm, and 1 mm from the top of the alveolar crest, respectively; working condition 6 had the miniscrew in the center of the buccal tongue at the anterior edge of the ascending branch of the lower jaw 5 mm above the occlusal plane.@*Results@#On the sagittal axis, miniscrew anchorage caused distal displacement of all teeth. Compared to the control group, in the miniscrew group, the displacement of the anterior molars exceeded that of the second molars. On the vertical axis, the result in the control group was similar to backward bending; the results in the miniscrew groups resembled the effect of a lever, lowering the lateral incisors and canines and raising the central incisors and first premolars. On the coronal axis, the second premolars and the first molars showed lingual displacement in the control group, and only the premolars and first molars showed lingual displacementin the miniscrew groups. The canines were the teeth that were most strongly affected by the change in miniscrew placement height.@*Conclusion@#The higher the miniscrew position is, the stronger the protective effect on the anterior anchorage. According to the miniscrew placement height, the mandibular arch should be properly narrowed, the central incisors and first premolars should be lowered, and the lateral incisors and canines should be raised when designing clinical treatments.
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BACKGROUND:The application of miniscrew in adolescents is increasing day by day,but at present,there are few studies on bone mass in the external oblique line of the mandible in adolescents at home and abroad,and there is no systematic study on bone mass in the external oblique line of the mandible in adolescents in different growth and development periods. OBJECTIVE:To measure the bone mass in the external oblique line of the mandible in adolescents with different cervical vertebral bone ages using a cone-beam CT and to investigate the difference of bone mass in the external oblique line of the mandible in adolescents with different cervical vertebral bone ages and the correlation between bone mass in this area and the cervical vertebral bone age. METHODS:The cone-beam CT data of 105 adolescent patients before orthodontic treatment were collected and divided into CS3 group(n=24),CS4 group(n=26),CS5 group(n=29)and CS6 group(n=26)using the cervical vertebral maturation method.The adolescent mandibular buccal shelf was reconstructed by Mimics Medical 21.0 software.The width of buccal bone at 6 and 11 mm under the cemento-enamel junction and the bone height at 4 and 5 mm buccal to the cemento-enamel junction of right mandibular first and second molars were measured.The measured data were statistically analyzed.The measurement was made on four planes:plane 1 is the plane where the proximal mesial root of the mandibular right first molar is located;plane 2 is the plane where the distal mesial root of the mandibular right first molar is located;plane 3 is the plane where the proximal mesial root of the mandibular right second molar is located;and plane 4 is the plane where the distal mesial root of the mandibular right second molar is located. RESULTS AND CONCLUSION:In each group,the bone width on the buccal side of the external oblique line increased gradually from the first molar proximally to the second molar distally in adolescents,and the width of buccal bone at 6 and 11 mm under the cemento-enamel junction showed significant difference among different layers(P<0.05).The bone width of buccal bone at 11 mm under the cemento-enamel junction was greater than that at 6 mm.The bone height on the buccal side of the external oblique line increased gradually from the first molar proximally to the second molar distally in all four groups,and the bone height at 4 and 5 mm buccal to the cemento-enamel junction showed significant differences at different layers(P<0.05).The bone height at 4 mm buccal to the cemento-enamel junction was greater than that at 5 mm.On the fourth plane,the bone width at 11 mm buccal to the cemento-enamel junction was smaller in the CS3,CS4,and CS5 groups than in the CS6 group(P<0.05).On the third plane,the bone heights at 4 mm and 5 mm buccal to the cemento-enamel junction were smaller in the CS3 and CS4 groups than in the CS6 group(P<0.05).On the fourth plane,the bone height at 5 mm buccal to the cemento-enamel junction was smaller in the CS3 and CS4 groups than in the CS6 group(P<0.05).On the fourth plane,the bone height at 4 mm buccal to the cemento-enamel junction was smaller in the CS3 group than in the CS6 group(P<0.05).Spearman correlation analysis showed that there was no correlation between bone mass and the cervical vertebral bone age,except that there was a weak correlation between bone mass at some measurement sites and cervical vertebral bone age.To conclude,the bone mass in the external oblique area of the mandible in adolescents does not change significantly with the increase of cervical vertebral bone age.The buccal side of the mesial root and distal root of the mandibular second molar in the external oblique area of CS3-CS6 adolescents meets the requirement of bone mass for miniscrew implantation,which is a site available for miniscrew implantation.
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BACKGROUND:Some studies have found that local application of alendronate can promote osteogenesis,but less is reported on the process of distraction osteogenesis. OBJECTIVE:To observe the promoting effect of alendronate on rapid mandibular distraction in a rabbit model and explore its possible mechanism. METHODS:Thirty-six male New Zealand white rabbits were randomly divided into groups A,B and C(n=12 per group)after operation and rapid distraction(3-day delay period followed by 3-day distraction at 1.5 mm/12 hours).At the 1st,3rd and 7th days of the consolidation period,animal were injected with 200 μg/kg alendronate in group A and 100 μg/kg alendronate in group B,while those in group C were treated as controls.CT scanning and dual energy X-ray bone mineral density measurement were performed at 4 and 8 weeks of the consolidation period.After the radionuclide scanning was completed at the 4th week,several animals were sacrificed and the samples were collected for western blot assay and tartrate resistant acid phosphatase staining.A three-point bending test was performed after the animals were sacrificed at the 8th week. RESULTS AND CONCLUSION:CT results showed that bone formation in the distraction space of group B was significantly better than that in groups A and C.At the 4th week,the bone mineral density in group B was(0.092±0.010)g/cm2,which was 1.26 times higher than that in group A(P<0.001)and 1.28 times higher than that in group C(P<0.001).At the 8th week,the bone mineral density in group B was(0.175±0.029)g/cm2,which was 1.38 times higher than that in group A(P<0.001)and 1.45 times higher than that in group C(P<0.001).Tartrate resistant acid phosphatase staining showed that the number of osteoclast-like cells in group C were 2.83 times more than that in group A(P<0.001)and 2.21 times more than that in group B(P<0.001).The radionuclide intensity was higher in group C than in groups A and B.Western blot assay results showed that the expression of Runx2 was significantly stronger in group B than in groups A and C.The maximum biomechanical load in group B was(158.48±23.21)N,which was 1.26 times higher than that in group A(P=0.007)and 1.31 times higher than that in group C(P=0.003).To conclude,the low concentration of alendronate may promote rapid distraction osteogenesis of the rabbit mandible by inhibiting osteoclast signals.
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ABSTRACT Sex determination plays a crucial role in the post-mortem identification of human remains. One effective approach for obtaining sex-related data is to use measurements of anatomical structures such as the mandible. This study aimed to evaluate the potential of mandibular radiomorphometric indices from panoramic radiographs (PRs) for the identification of sexual dimorphism. The study sample included 300 PRs of individuals aged 51 to 80 years from the northeastern region of Brazil. Four linear measures and three numerical indices were analyzed with Inkscape® version 1.0.1 for Windows by two blinded evaluators. After statistical analysis, the results showed that the linear measurements obtained from PRs are a reliable method for sex identification. However, the calculated indices of these measurements exhibited lower efficacy for the same purpose. Therefore, PRs proved to be a valuable method for sexual identification through mandibular assessment.
RESUMO A determinação do sexo é um dado importante para a identificação post-mortem de um indivíduo ou de restos mortais humanos. Uma maneira de adquirir dados quanto ao sexo é utilizar mensurações de estruturas como a mandíbula. O objetivo principal deste estudo é avaliar a utilização de índices radiomorfométricos de mandíbulas para a identificação de dimorfismo sexual, através de radiografias panorâmicas. O estudo foi realizado em exames radiográficos panorâmicos de 300 indivíduos entre 51 e 80 anos, residentes do Nordeste brasileiro. Foram analisadas quatro medidas lineares e três índices numéricos no software Inkscape® versão 1.0.1 para Windows, por dois avaliadores cegos. Após análise estatística, os resultados demostraram que as medidas lineares obtidas se configuram como um método seguro para a identificação sexual. Entretanto, os índices obtidos através destas medidas demostraram menor eficiência para o mesmo fim. Logo, as radiografias panorâmicas podem ser utilizadas como método eficaz para a obtenção da caracterização sexual através da mandíbula.
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ABSTRACT Objective: To compare the accuracy of working length determination between cone beam computed tomography (CBCT) and electronic apex locator by measuring the actual working length of teeth. Material and Methods: A total of 150 single-rooted tooth assessed by radiograph undergoing root canal therapy were selected. The process was repeated to obtain a buccolingual and mesiodistal section of all teeth. The measurement line was considered from the reference occlusal plane following the center of the canal to the terminus. All information regarding the accuracy of cone-beam computed tomography and apex locator was noted in a pre-designed proforma. Results: CBCT consistently demonstrated high accuracy across all tooth types in both jaws. The electronic apex locator exhibited varying precision, with greater accuracy observed in the mandible. Statistical analyses revealed significant differences in electronic apex locator accuracy among tooth types in the maxilla (p=0.042), emphasizing the importance of specific clinical considerations. Conclusion: Cone beam computed tomography emerges as a reliable diagnostic tool for accurate working length determination, especially in complex cases, while the electronic apex locator remains valuable with careful consideration of potential variations in accuracy. An individualized approach, considering tooth type, jaw location, and clinical context, is crucial for precise working length determination in endodontic practice.
الموضوعات
Humans , Male , Female , Radiography, Dental/instrumentation , Endodontics , Cone-Beam Computed Tomography/instrumentation , Maxilla , Odontometry/instrumentation , In Vitro Techniques , Chi-Square Distribution , Dental Pulp Cavityالملخص
Introdução: A mandíbula é o maior e mais forte dos ossos da face. Em razão de sua topografia, apresenta vulnerabilidade nos traumas. A análise de dados sobre as fraturas de mandíbula se mostram fundamentais para auxiliar no tratamento e em políticas de saúde pública. O objetivo desse estudo é realizar um levantamento epidemiológico de fraturas mandibulares tratadas cirurgicamente. Método: Triagem através do sistema de informação hospitalar, buscando pacientes submetidos a cirurgia para fratura de mandíbula realizadas em um hospital escola pela equipe de cirurgia plástica, em Campinas-SP, de abril de 2015 a abril de 2020. Foram, então, coletados dados por meio da análise de prontuários. Resultados: Foram incluídos 50 pacientes, sendo 90% do sexo masculino. A média de idade foi 30,7 anos. A etiologia predominante foi acidente automotivo e a região mais fraturada na mandíbula foi a parassínfise. A mediana de tempo entre o trauma e cirurgia foi de 19 dias. Onze (22%) pacientes apresentavam alguma comorbidade. Quatorze pacientes (28%) foram internados em Unidade de Terapia Intensiva (UTI) e 42% operaram com outra especialidade além da Cirurgia Plástica. Dez (20%) pacientes apresentaram alguma complicação da cirurgia, sendo a mais comum a deiscência de ferida operatória. Conclusão: Houve predominância entre homens jovens e de acidentes de trânsito como etiologia. As fraturas foram localizadas preferencialmente na região da parassínfise e foram tratadas por meio de fixação interna rígida. Os elevados índices de internação em UTI, lesões associadas e realizações de procedimentos cirúrgicos por outras especialidades evidenciam a gravidade dos pacientes assistidos no serviço.
Introduction: The mandible is the largest and strongest of the bones in the face. Due to its topography, it is vulnerable to trauma. Data analysis on mandible fractures is fundamental for treatment and public health policies. This study aims to conduct an epidemiological survey of surgically treated mandibular fractures. Method: Screening through the hospital information system, seeking patients undergoing surgery for jaw fracture performed at a teaching hospital by the plastic surgery team in Campinas-SP from April 2015 to April 2020. Data were then collected through analysis of medical records. Results: 50 patients were included, 90% male. The average age was 30.7 years. The predominant etiology was an automobile accident, and the most fractured region in the mandible was the parasymphysis. The median time between trauma and surgery was 19 days. Eleven (22%) patients had some comorbidity. Fourteen patients (28%) were admitted to the Intensive Care Unit (ICU), and 42% underwent surgery with another specialty besides Plastic Surgery. Ten (20%) patients had some complication of the surgery, the most common being surgical wound dehiscence. Conclusion: There was a predominance among young men and traffic accidents as etiology. Fractures were preferably located in the parasymphysis region and were treated using rigid internal fixation. The high rates of ICU admission, associated injuries, and surgical procedures carried out by other specialties demonstrate the severity of the patients assisted in the service.
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Objective: Assessing whether it is possible screening women with osteoporosis through geometric morphometrics based on panoramic x-ray. Materials and Methods: Leukoderma women, after menopause, 40 years old (or older), with confirmed medical diagnosis of presence, or absence, of osteoporosis through bone densitometry examination. (N = 62). Measurements taken through panoramic X-ray based on geometric morphometrics. All x-rays were taken twice by the same researcher. Procrustes superimposition was assessed through Cartesian coordinates generated from anatomic landmark and semilandmarks. Regression Analysis, Multivariate Analysis of Variance (MANOVA), discriminant function and cross validation analysis, and Thin plate spliness in MorphoJ software were carried out. Subsequently, Fluctuating Asymmetry Analysis (FA) was conducted and ANOVA was performed to assess differences in centroid size. Results: Significant values were recorded for mandible shape (p<0.01) through MANOVA. Significant values (P<0.01) were also found through discriminant function analysis between groups of women with, and without, osteoporosis. Fluctuating asymmetry analysis showed significant differences in mandible shape and size between sides (p<0.01). Conclusions: Geometric morphometrics proved to be effective in screening and identifying elderly leukoderma women with, or without, osteoporosis based on panoramic x-rays. This is a promising technique to diagnose or identify patients with some health condition.
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Introduction: extraction of lower third molars involve the possible occurrence of complications such as injury of the content of the Inferior Alveolar Canal. Methods: a cross-sectional study was conducted with a sample of 6488 lower molar records of digital panoramic radiographs of patients from 6 Latin American countries from 2010-2015. The variables studied were the depth of lower third molar according to the Pell and Gregory classification, and the proximity of a third molar to the Inferior Alveolar Canal that was evaluated according to the proposed classification, based on a modification of the Langlais et al classification.20 Descriptive and bivariate statistical analyses were performed. Results: in terms of the proximity, the highest frequency was Intact with 27.45%(n=1781). Regarding the depth of the lower third molar, the most frequent were the Position B with 46.90%(n=3043) and Position A with 46.75%(n=3033). The proximity and depth of the lower third molar had statistical difference according to age(p<0.01) and sex (p<0.001). The overall proximity of the lower third molar to the Inferior alveolar canal, according to depth was 37.52%(n=1766) in Position A, in Position B it was 54.51%(n=2566) and Position C was 7.97%(n=375) and had association between variables(p<0.001). Conclusions: taking into consideration the modified classification of Langlais et al.20, lower third molars are close to the Inferior Alveolar Canal, and according to the Pell and Gregory classification for the depth, the most frequent positions are A and B. In addition, proximity and depth were associated with each other, and with the co-variables country, age, and sex.
Introducción: la extracción de terceros molars inferiores implica la posible aparición de complicaciones, como la lesión del contenido del Canal Alveolar Inferior. Métodos: se realizó un estudio transversal con una muestra de 6488 registros de terceros molares inferiores de radiografías panorámicas digitales en pacientes de 6 países latinoamericanos, entre 2010-2015. Las variables fueron profundidad del tercer molar inferior según la clasificación de Pell y Gregory, y proximidad del tercer molar al Canal Alveolar Inferior, evaluada según una clasificación propuesta, basada en la clasificación modificada de Langlais et al.20 Se realizaron análisis estadísticos descriptivos y bivariados. Resultados: en la proximidad, la mayor frecuencia se presentó en Intacto con 27,45%(n=1781); en cuanto a la profundidad del tercer molar inferior, las más frecuentes fueron la Posición B con 46,90%(n=3043) y la Posición A con 46,75%(n=3033). La proximidad y profundidad del tercer molar inferior presentaron diferencias estadísticas de acuerdo con la edad (p<0,01) y sexo (p<0,001). La proximidad total del tercer molar inferior al canal alveolar inferior, según la profundidad fue de 37,52%(n=1766) en Posición A, en Posición B de 54,51%(n=2566) y Posición C de 7,97%(n=375). Además, se presentó asociación entre las variables (p<0,001). Conclusiones: considerando la clasificación modificada de Langlais et al.20, la mayoría de los terceros molares inferiores están próximos al canal alveolar inferior; y según la profundidad de Pell y Gregory, las posiciones más frecuentes son A y B. Además, la proximidad y la profundidad se asociaron entre sí, y con las co-variables país, edad y sexo.
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SUMMARY: Sex identification of a deceased human individual by means of the mandible is very important for forensic dentistry. The aim of the present study was to determine the sex of Chilean individuals by mandible analysis in panoramic radiographies. Linear and angular parameters of the mandible were analyzed from panoramic radiographies (PR). The study included PR of adult Chilean individuals, of both sexes, with optimum solution and contrast, and which allowed the angles and rami of the mandible to be viewed. Sex was determined by univariate and bivariate discriminant function analysis. The sample consisted of 594 PR of individuals aged between 18 and 84 years. The best sex predictor using univariate discriminant function analysis was the mandibular ramus height (MRH) (74.1 %), followed by the distance from the mental foramen - mandibular base (DMF-MB) (69.1 %) and the bicondylar breadth (BC) (66.7 %). The parameters that presented the lowest sex prediction were the angle of the mandible (AM) with 55.0 % and the distance between mental foramina (DMF) with 53.7 %. The best sex prediction was obtained by the step model of discriminant function analysis (80.2 %), including only three parameters: MRH, BC and DMF-MB. The parameters height of the mandibular ramus, bicondylar breadth and distance from the mental foramen - base of the mandible are good predictors of sex in Chilean individuals when used in conjunction; they are therefore indicated for sex determination in the contemporary Chilean population.
La identificación humana de un individuo fallecido a través de la mandíbula es muy relevante para la odontología forense. El objetivo de este estudio fue estimar el sexo de individuos Chilenos a través del análisis de la mandíbula, utilizando radiografías panorámicas. Fueron analizados parámetros lineales y angulares de la mandíbula, a través de radiografías panorámicas (RP). Se incluyeron RP de individuos chilenos adultos, ambos sexos, con solución y contraste óptimos, y que permitían la visualización de los ángulos y ramas de la mandíbula. Se realizó análisis por función discriminante univariada y bivariada para estimación del sexo. Fueron incluidas 594 RP de individuos entre 18 y 84 años. Para el análisis de función discriminante univariado, la altura de la rama mandibular (ARM) fue el parámetro más predictivo (74,1 %), seguido de la distancia foramen mentoniano - base de la mandíbula (DFM-BM) (69,1 %) y el ancho bicondilar (ABCo) (66,7 %). Los parámetros que presentaron menor predicción sexual fueron el ángulo de la mandíbula (AM) con un 55,0 % y la distancia inter-forámenes mentonianos (DIFM), con el 53.7 %. El análisis por pasos fue el modelo de análisis de función discriminante que presentó la mayor predicción sexual (79,5 %), en el cual fueron incluidos sólo tres parámetros: ARM, ABCo y DFM-BM. Los parámetros altura de la rama de la mandíbula, ancho bicondilar y distancia desde el foramen mentoniano hasta la base de la mandíbula son buenos predictores del sexo en individuos Chilenos cuando utilizados en conjunto y están indicados para estimar el sexo en la población chilena contemporánea.
الموضوعات
Humans , Male , Female , Adolescent , Adult , Middle Aged , Aged , Aged, 80 and over , Young Adult , Sex Determination by Skeleton , Mandible/diagnostic imaging , Radiography, Panoramic , Discriminant Analysis , Chile , Cross-Sectional Studies , Multivariate Analysis , Forensic Dentistry , Mandible/anatomy & histologyالملخص
The mandibular advancements performed in orthognathic surgeries can be stabilized with several techniques when using stable internal fixation. This study aims to comparatively evaluate, in vitro, the mechanical strength in a polyurethane mandibular model for four fixation techniques for sagittal split ramus osteotomy mandibular. 60 samples were divided into 4 groups, with 15 units for each group: group A, group B, group C and group D. Advances of 5 mm were made for each subgroup and fixed with 2.0 mm system plates and monocortical screws in the replicas of human hemimandibles in polyurethane resin. The samples were submitted to mechanical tests of linear loading, being evaluated the peak load and peak deformation. Technique B presented higher peak load (Kgf) and techniques A and B presented higher peak strain (p<0.05). Technique D presented lower peak load and lower peak strain (p<0.05). It is concluded that the study based on the development of new techniques for fixation for sagittal osteotomy of the mandibular ramus is of great importance for the advancement of orthognathic surgery, provided by the technical innovation of more favorable plate models.
Los avances mandibulares realizados en cirugías ortognáticas pueden estabilizarse con varias técnicas cuando se utiliza fijación interna estable. Este estudio tuvo como objetivo evaluar comparativamente, in vitro, la resistencia mecánica en un modelo mandibular de poliuretano para cuatro técnicas de fijación para la osteotomía sagital de la rama mandibular. Se dividieron 60 muestras en 4 grupos, con 15 unidades para cada grupo: grupo A, grupo B, grupo C y grupo D. Se realizaron avances de 5 mm para cada subgrupo y se fijaron con placas de sistema de 2,0 mm y tornillos monocorticales en las réplicas de hemimandíbulas humanas en resina de poliuretano. Las muestras fueron sometidas a pruebas mecánicas de carga lineal, siendo evaluadas la carga máxima y la deformación máxima. La técnica B presentó mayor pico de carga (Kgf) y las técnicas A y B presentaron mayor pico de deformación (p<0,05). La técnica D presentó menor carga máxima y menor tensión máxima (p<0,05). Se concluye que el estudio basado en el desarrollo de nuevas técnicas de fijación para la osteotomía sagital de la rama mandibular es de gran importancia para el avance de la cirugía ortognática, proporcionada por la innovación técnica de modelos de placas más favorables.
الموضوعات
Mandibular Advancement/methods , Osteotomy, Sagittal Split Ramus/methods , Mandible/surgery , Biomechanical Phenomena , Orthognathic Surgery/methods , Fracture Fixation, Internal/methodsالملخص
Introduction: ameloblastomas correspond to one of the most prevalent odontogenic tumors in developing countries, they are mainly located in the mandible, and their treatment has been widely discussed over the years, using radical or conservative treatments depending on different variables. Clinical case: we present two cases of patients with ameloblastoma who underwent conservative treatment without the use of adjuvant therapy, obtaining satisfactory results at 36 and 48 months. Discussion: due to a possible recurrence with conservative treatment, radical management has been suggested, however, the choice of treatment should be based on a series of clinical, histological, and radiographic characteristics.
Introducción: Los ameloblastomas corresponden a uno de los tumores odontogénicos más prevalentes en los países en desarrollo, se ubican principalmente en la mandíbula, y su tratamiento ha sido ampliamente discutido a lo largo de los años, utilizando tratamientos radicales o conservadores dependiendo de distintas variables. Caso clínico: se presentan dos casos de pacientes con un ameloblastoma a quienes se les realizó tratamiento conservador sin uso de terapia coadyuvante, obteniendo resultados satisfactorios a los 36 y 48 meses. Discusión: Debido a una posible recurrencia con un tratamiento conservador, se ha sugerido manejo radical, sin embargo, la elección de tratamiento debe ser en base a una serie de características clínicas, histológicas y radiográficas.
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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.
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Introduction: Squamous odontogenic tumor is a benign but locally infiltrative, epithelial odontogenic tumor. This case report presents a case of a peripheral variant of squamous odontogenic tumor. Case Presentation: A 29-year-old male patient presented with pain in the left posterior mandible region for one month. Radiographic examination revealed an impacted left mandibular third molar with no other abnormalities. Management and Prognosis: The impacted tooth was removed under local anaesthesia. Histopathological examination of the abnormally thick pericoronal tissue, covering the impacted tooth revealed islands of bland squamous epithelium in a background of mature fibrous connective tissue. The prognosis was good with no signs of recurrence after one year of follow- up. Conclusion: Squamous odontogenic tumor should be considered in the differential diagnosis of pericoronal pathoses, although it is rare in this location.