Root canal morphology of the mandibular second premolar: a systematic review and meta-analysis.

BACKGROUND: The aim of this paper was to systematically review the root canal configuration (RCC) and morphology literature of the mandibular second premolar (Mn2P). METHODS: Systematic research of five electronic databases was performed to identify published literature concerning the root canal configuration (RCC) of the Mn2P up through July 2020. Studies were selected according to predefined search terms and keywords inclusion criteria: "root canal configuration", "root canal system", "root canal morphology", "mandibular second premolar", "mandibular premolars", "morphology" and "anatomy". Further possible studies were identified by cross-referencing and screening the bibliographies of the selected articles. RESULTS: From 1622 retrieved studies, 44 studies investigating the internal morphology of 17,839 Mn2Ps were included. Most examined Mn2Ps were single-rooted (89.5-100%); two-rooted (0.1-8%) and three-rooted (0.1-3.5%) Mn2Ps at lower frequency. Most frequent RCCs reported were 1-1-1/1 (55.3-99.6%) followed by 1-1-2/2 (0.5-57%) and 2-2-2/2 (0.6-18%). The meta-analysis of seven studies demonstrated that a significantly higher number of RCC type 1-2-1/1 (OR [95%CI] = 2.05 [1.27, 3.33]) and 2-2-2/2 (OR [95%CI] = 2.32 [0.65, 8.63]) were observed in male than in female patients. CONCLUSIONS: Different RCC research methods have been reported. Whereas clearing and radiographs were commonly used in the past, CBCT has been prevalent in recent years. A globally high frequency of a 1-1-1/1 RCC in the Mn2P has been reported. Nevertheless, the probability that different, more complicated RCCs can appear in Mn2Ps should not be underestimated and, thus, should be taken into consideration when making decisions during an endodontic treatment.

Molar superior con dos raíces palatinas: descripción de un caso / Upper molar with two palatine roots: a case description / Molar superior com duas raízes palatinas: uma descrição do caso

Antecedentes: La morfología radicular en molares superiores presenta menos variabilidad anatómica, sin embargo, es muy importante tener en cuenta que existen alteraciones anatómicas, y que aun no están bien fundamentadas, se asocia a hiperactividad en la vaina epitelial de Hertwig o bien asociados a factores externos durante la odontogénesis. Descripción del caso: El presente artículo relata un caso de un segundo molar superior derecho con pulpitis irreversible sintomática, en el examen radiográfico se observa la existencia de una raíz supernumeraria palatina. Se realizó tratamiento endodontico con ProtaperNext® y se obturó con técnica lateral modificada con ultrasonido. Conclusión: Los molares con raíces supernumerarias requieren del conocimiento y experiencia del clínico para integrar los métodos de diagnóstico tales como exámenes radiográficos, tomográficos, de microscopía así como técnicas para el tratamiento endodóntico.

Background: Radiographic examination in upper molars is often deficient in order to diagnose abnormalities in the root canal system and to be able to choose the ideal treatment. Description of the case: This article shows the clinical case of a second right upper molar with symptomatic irreversible pulpitis. An accessory root on the palatal is observed in a radiographic examination. A therapy of the canal was carried out with ProtaperNext ® and the sealing was made by cold lateral condensation with ultrasonic condensation. Conclusión: It is very important to know the root canal system morphology of the tooth to be treated in order to offer the patient an adequate treatment.

Antecedentes: O exame radiográfico em molares superiores é frequentemente deficiente para diagnosticar anormalidades no sistema de canais radiculares e para poder escolher o tratamento ideal. Descrição do caso: Este artigo mostra o caso clínico de um segundo molar superior direito com pulpite irreversível sintomática. Uma raiz acessória no palato é observada em um exame radiográfico. A terapia do canal foi realizada com ProtaperNext ® e a vedação foi feita por condensação lateral fria com condensação ultra-sônica. Conclusão: É muito importante conhecer a morfologia do sistema de canais radiculares do dente a ser tratado, a fim de oferecer ao paciente um tratamento adequado.

Study on the application of cone-beam CT in root canal morphology of first deciduous molars / 口腔疾病防治

Objective@#To analyze the number, distribution of root canals in children's first deciduous teeth through a retrospective study of cone-beam computed tomography (CBCT). @* Methods@#A total of 185 first deciduous molars were selected from 91 children aged 4 to 8 years old in the Stomatology Department of Mianyang Hospital of Traditional Chinese Medicine. The number, distribution of root canals were analyzed.@* Results @#All 46 maxillary first deciduous molars had three roots; 139 mandibular first deciduous molars had two roots (77.70%) and three roots (22.30%). The root canals of all maxillary first deciduous molars are type Ⅰ, while the main root canal type of mandibular first deciduous molars is type Ⅳ. Of 51 children with bilateral mandibular first deciduous molars, 48 (94.12%) had symmetrical root and canal distributions.@*Conclusion @#The first deciduous molars usually have 2 to 3 roots. Root canals are mainly type I and IV. The distribution of root canals is symmetrical.