ABSTRACT
It has been known that the retromolar foramen is a rare anatomic variation observed in the retromolar triangle, a small triangular shaped region posterior to the mandibular third molar. Due to the neurovascular bundle passing through the retromolar foramen, this anatomical structure must be kept in mind during surgical approaches regarding the retromolar area and mandible. Therefore, the authors investigated the morphology of retromolar triangle and the existence and location of retromolar foramen in Korean. And these results were compared with that of other races. We used 308 sides of 154 Korean dry mandibles, unknown gender and age. The retromolar triangle presented predominantly a triangular shape (84.1%), and the maximum height and width were 13.7 mm and 7.1 mm, respectively. In 144 of the 308 sides, the retromolar foramen was observed (46.8%). The existence of the retromolar foramen was seen the same frequency in both sides, and based on a midsagittal line of the retromolar triangle, the retromolar foramen located in more buccal side (75%) than lingual side. The mean distance between the retromolar foramen and the distal edge of the last tooth were found to be 10.3 mm and 6.9 mm, respectively for the second and third molars. According to the present study, the northeast Asians including Korean population show the highest rate of the incidence of the retromolar foramen than other races. The findings suggest that practitioners should take the retromolar foramen into account in surgical procedures involving the retromolar area to protect the patient from the complications such as bleeding or nerve damage.
Subject(s)
Humans , Anatomic Variation , Asian People , Racial Groups , Hemorrhage , Incidence , Mandible , Molar, Third , ToothABSTRACT
The lower third molar region is an important region for the odontostomatological practice, since it presents a great amount of pathological processes related to the development and eruption of the third molar; thus having a considerable number of surgical interventions. Despite its importance, this region is not accounted for in anatomical terminology nor is it described in topographic anatomy; and in spite of the great number of studies that analyze the surgical anatomy of the region, it is necessary to systematize the description of its boundaries, planes, content, risk elements, anatomical repairs, etc.; therefore, the purpose of the present article is to review the modern concepts related to the surgical anatomy of the lower third molar region and to establish a description based on these concepts...
La región del tercer molar inferior es una región importante para la práctica odontoestomatológica, en ella se presenta una gran cantidad de procesos patológicos relacionados con el desarrollo y erupción del tercer molar, por lo que se practican un gran número de intervenciones quirúrgicas. No obstante su importancia, esta región no se encuentra considerada en la terminología anatómica ni descrita en la anatomía topográfica y a pesar de la gran cantidad de estudios que analizan la anatomía quirúrgica de la región, es necesario sistematizar la descripción de sus límites, planos, contenidos, elementos de riesgo, puntos de reparo, etc., es por ello que el propósito de este artículo es revisar los conceptos modernos relacionados con la anatomía quirúrgica de la región del tercer molar inferior y proponer una descripción basada en estos conceptos...
Subject(s)
Humans , Mandibular Nerve/anatomy & histology , Molar, Third/anatomy & histology , Mandible/anatomy & histology , Lingual Nerve/anatomy & histology , Surgery, Oral , Molar, Third/innervation , Molar, Third/blood supplyABSTRACT
El trígono retromolar es un área triangular ubicado en la mandíbula, posterior al último molar. Esta región, debido al grosor y densidad ósea que presenta, es utilizada para la instalación de dispositivos que ofrezcan un sistema de anclaje para el movimiento de los molares inferiores. El objetivo de esta investigación es ofrecer datos morfométricos del grosor de la mucosa de región del trígono retromolar. Se utilizaron 25 pacientes de nacionalidad portuguesa, con indicación de exodoncia del tercer molar inferior retenido (derecho y/o izquierdo). En la región del trígono retromolar fueron demarcados 3 puntos correspondientes a los vértices de un triángulo cuya base se quedaba dirigida hacia la cara distal del tercer molar inferior y el largo de las vertientes correspondían a la dimensión vestíbulolingual del mismo diente; luego fue demarcado un cuarto punto correspondiente al centro geométrico del triángulo. Con un espaciador digital puntiagudo con tope de silicona incorporado se hizo la medición del grosor de la mucosa en cada punto. Los datos obtenidos fueron tabulados y analizados. El menor valor promedio encontrado fue 5,5mm en el lado derecho y el mayor fue 7,13mm en el lado izquierdo. Considerando los valores promedios obtenidos en los puntos de la mucosa, concluimos que la región del trígono retromolar presenta una mucosa gruesa, por lo tanto, los mini implantes indicados para esta región deben tener cuello transmucoso largo.
The retromolar triangle is a triangular area located in the mandible, posteriorly to the last molar. This region, due its thickness and bone density, is widely used for the installation of devices that provide an anchorage system for the movement of the lower molars. The aim of this research is to provide morphometric data of the mucosa thickness of the retromolar triangle. Twenty-five patients of portuguese nationality, with indication for extraction of the impacted lower third molar (right and/or left), were studied. In the region of the retromolar triangle were demarcated 3 points corresponding to the vertices of a triangle whose the base was torned for the distal face of the lower third molar and the lenght of the sides corresponded to vestibulolingual dimension of the same tooth, then was demarcated a fourth point corresponding to the geometric center of the triangle. Then, using a finger spreader with silicone stop were measured the mucosal tickness at each point. The data obtained were tabulated and analyzed. The lowest average value found was 5.5mm on the right side and the highest average value found was 7.13mm on the left side. Considering the mean values obtained at the points of the retromolar triangle mucosa measured in this study, we conclude that the retromolar triangle shows thick mucosa, so the mini-implants indicated for this region should have a long transmucosal neck.
Subject(s)
Humans , Male , Female , Adolescent , Adult , Dental Implants , Dental Implantation, Endosseous/methods , Mandible/anatomy & histology , Miniaturization , Mouth Mucosa/anatomy & histologyABSTRACT
The main mandibular anesthesia techniques used are directed to the mandibular lingula and Gow-Gates, especially the former presents considerable surgical risks, including intravascular puncture, which is presented in 1520 percent of the cases. In this study, we applied this anesthetic technique to the inferior alveolar nerve via the retromolar triangle in 20 patients who were 4060 years old to evaluate its effectiveness, determine the latency time, and ascertain whether the anesthesia administered is sufficient to carry out the surgery and endodontics. The technique proved to be effective in 75 percent of the cases, measured and controlled with pre-vitalometer test at 5, 10, and 15 minutes. Because this technique is simple, minimally invasive,and involves low risk, it is recommended as an alternative to conventional mandibular anesthetic techniques in patients with blood dyscrasias and patients who are suspected to submit to arterial hypertension but require anesthesia with vasoconstrictor.
Las principales técnicas anestésicas mandibulares usadas son la dirigida a la língula mandibular y la Gow-Gates, especialmente la primera, la cual presenta un importante porcentaje de riesgos operatorios, destacándose la punción intravascular, la cual se presenta en un 15- 20 por ciento de los casos. En este estudio se aplicó esta técnica anestésica al nervio alveolar inferior vía trígono retromolar en 20 pacientes de 40 a 60 años de edad con el fin de evaluar su efectividad, determinar los tiempos de latencia y averiguar si la anestesia conseguida es suficiente para realizar trabajos de operatoria y endodoncia. La técnica resultó ser efectiva en el 75 por ciento de los casos, medida con vitalometría previa y controlada a los 5, 10 y 15 minutos. Esta técnica se recomienda como una alternativa a las técnicas anestésicas convencionales mandibulares en pacientes con discrasias y en pacientes que se sospeche que presenten hipertensión arterial y se requiera usar anestésico con vasoconstrictor; debido a que es una técnica sencilla, poco invasiva y de bajo riesgo.