An endodontic sealer induces a pathological condition when associated with persistent tissue toxicity and presence of myofibroblasts

The aims of this study were to evaluate the ratio between inflammatory reactions induced by four endodontic sealers and the occurrence of fibrosis and the number of myofibroblasts with positivity to α-smooth-actin muscle (α-SMA). Polyethylene tubes were filled with a root canal sealer (Endofill, AH Plus, Acroseal and Epiphany) and inserted into 4 site at the dorsal region of 24 Wistar rats; 2 empty tubes (control) were grafted in 6 rats. After 7, 21, and 45 days, 8 animals were euthanized, providing 6 specimens per test group and 2 specimens from the control group. The fragments were subjected to histological processing and immunohistochemical analysis for anti α-SMA protein. All specimens, except those from the control group, presented severe inflammatory reaction on the 7th postoperative day, which also coincided with a large number of myofibroblasts. On the 21st and 45th days post-surgery, the inflammatory reaction induced by Endofill, AH Plus and Acroseal decreased significantly, which coincided with reduced presence of myofibroblasts and usual collagen deposition. In contrast, in the group filled with Epiphany, significant inflammatory cell infiltrate was present in all analyzed periods. The persistence of an inflammatory reaction induced by endodontic sealer may also induce the development of fibrosis in combination with presence of myofibroblasts.

O objetivo deste estudo foi avaliar a relação entre reação inflamatória induzida por quatro cimentos endodônticos e a presença de fibrose e quantidade de miofibroblastos que apresentam positividade para α-SMA. Tubos de polietileno foram preenchidos com o cimento (I: Endofill; II: AH Plus; III: Acroseal; IV: Epiphany) e inseridos em 4 regiões do dorso de 24 ratos Wistar, enquanto 2 tubos vazios (V - controle) foram inseridos em 6 ratos. Após 7, 21 e 45 dias, oito animais foram sacrificados obtendo 6 indivíduos por grupo e 2 para o grupo controle. Os fragmentos foram submetidos ao processamento histológico e à análise imuno-histoquímica para a proteína anti-α-SMA. Todos os grupos, exceto o controle, demonstraram notável reação inflamatória no 7º dia pós-operatório, que também coincidiu com uma grande quantidade de miofibroblastos. No 21º e 45º dia pós-operatório, a reação inflamatória induzida pelo Endofill, AH Plus e Acroseal diminuiu significativamente, o que coincidiu com reduzida presença de miofibroblastos e deposição de colágeno normal. Em contraste, no grupo Epiphany, infiltrado inflamatório significativo esteve presente em todos os períodos analisados. A persistência do infiltrado inflamatório induzido por cimento endodôntico pode também provocar uma fibrose associada com a presença de miofibroblastos.

Evaluation of professors and students knowledge on crown-root fractures

Objective: The aim of this study was to evaluate the knowledge on crownrootfractures among professors and students of a school of dentistry.Material and methods: A questionnaire comprising the treatment optionsfor crown-root fractures at different depths and their follow-up periodswas applied to 122 subjects divided into three groups: 1) students whohad not attended any Endodontics and Surgery disciplines, 2) studentswho had concluded these disciplines; and 3) professors. The data wasanalyzed by descriptive statistics. Results: Most of Group 1 (90.3%) didnot know the procedures to be adopted in cases of crown-root fractures.Conversely, more than 80% of Group 2 and 95% of Group 3 knew theprocedures. Concerning to crown-root fractures up to 2mm deep, 26.9%of Group 1 and 48.5% of Group 3 would perform crown lengthening;46.2% of Group 2 would perform fragment rebonding. In relation tofractures between 2 and 4mm deep, 21.2% of Group 1 would performtooth extraction; 28.6% of Group 2, fragment rebonding; and 40.7%of Group 3, orthodontic extrusion. In fractures more than 4mm deep,most members of all groups would perform tooth extraction followed byimplant. With regard to follow-up appointments, most members of allgroups stated that their frequency should be at every 6 months (duringthe first year) and every year (for 5 years). Conclusion: Students of Group1 showed poor knowledge on crown-root fractures, while members ofGroups 2 and 3 showed a proper knowledge.

Tratamento endodôntico de pré-molares superiores com três raízes e três canais / Endodontic treatment of maxillary pre-molar teeth with three roots and three roots canals

Introdução: O conhecimento da anatomia interna dos dentes de humanos é um dos fatores determinantes para o sucesso do tratamento endodôntico. Algumas alterações anatômicas podem ser encontradas em maior ou menor freqüência durante o tratamento endodôntico, tornando-se importante o seu relato para um melhor entendimento do tema. Objetivo: Neste trabalho será abordado o tratamento proposto para pré-molares superiores com três raízes e três canais. Relato de caso: Avaliaram-se dois casos clínicos, um primeiro pré-molar direito e um primeiro pré-molar esquerdo, além de um primeiro pré-molar superior extraído, apresentando 3 raízes com 3 canais. Conclusão: Apresença de três canais nos pré-molares superiores aumenta a dificuldade de realizar o tratamento endodôntico nesse grupo dental.

Introduction: The knowledge of the internal anatomy of human teeth is one of the determinative factors for the success of the endodontic treatment. Some anatomical alterations can be found in greater or lesser frequency during the endodontic treatment, becoming important its knowledge for one better agreement. Objective: in this study the treatment considered for maxillary premolars teeth with three roots and three roots canals will be showed. Case report: two case report, one right and one left maxillary first premolar and one extracted maxillary premolar presenting three roots and three root canals. Conclusion: The presence of three canals in the maxillary premolars increases the difficulty of the accomplishment of the endodontic treatment in this dental group.