Gingival cyst of the adult

ABSTRACT The gingival cyst of the adult (GCA) is a rare odontogenic cyst, consisting of 0.3% of all odontogenic cysts. This case report, based on CARE guidelines for case reports, aims to present a case of a 52-year-old female patient with a symptomatic translucent nodule in the upper left anterior gingiva, measuring approximately 6mm. Excisional biopsy was performed, and the histological examination revealed multiple cystic cavities lined by the squamous epithelium of varying thickness with focal areas of nodular thickenings. The presence of clusters of cells with clear cytoplasm within epithelial thickenings was observed. PAS staining was negative in clear cells. The diagnosis of the GCA was established. Despite its rarity, GCA should be considered in the differential diagnosis of gingival lesions. Conservative surgical treatment proved to be effective, with no signs of recurrence.

Biological properties of experimental methacrylate-based sealers containing calcium phosphates

Abstract This study aimed to evaluate, in vitro and in vivo, the biocompatibility of experimental methacrylate-based endodontic sealers containing α-tricalcium phosphate (α-TCP) or nanostructured hydroxyapatite (HAp). Experimental methacrylate-based dual-cure sealers with the addition of α-TCP or HAp, at 10%wt were formulated and compared to AH Plus (AHP). Cell viability was assessed by 3-(4,5-dimethyl-thiazoyl)-2,5-diphenyl-tetrazolium bromide (MTT), and sulforhodamine B (SRB). Sealers were implanted in rats' subcutaneous tissue and histologically evaluated. Bioactivity was assessed by alkaline phosphatase enzyme activity (ALP) and Alizarin Red (AR), using apical papillary cells (SCAPs), and by the bone deposition measured in surgical cavities on rats' femur filled with AH Plus or α-TCP. In both viability assays, HAp and AHP sealers were similar, and α-TCP presented lower viability compared to the others at MTT assay (p<0.05). A gradual decrease of the inflammatory response according to the periods was observed and AHP was the only that presented giant cells (7-day period). Collagen fibers condensation increased according to the periods, with no differences among sealers. There was an increase at ALP activity and mineralized nodules deposition according to periods. HAp and α-TCP presented higher values for ALP activity at 5 days and at 5, 10, and 15 days for AR and were different from AHP (p<0.05). α-TCP presented superior values at 10 and 15 days compared to HAp and AHP for AR (p<0.05). At 90 days, α-TCP and control (empty cavity) showed high bone deposition compared to AHP (p<0.05). α-TCP and HAp, in a methacrylate-based sealer, presented biocompatibility and bioactivity, with the potential to be used as endodontic sealers in clinical practice. Further investigations are required to gain information on the physicochemical properties of these sealers formulation before its clinical implementation.

Resumo O objetivo deste estudo foi avaliar a biocompatibilidade de cimentos endodônticos experimentais à base de metacrilato contendo fosfato α-tricálcico ou hidroxiapatita nanoestruturada in vitro e in vivo. Cimentos experimentais de cura dual à base de metacrilato com a adição de fosfato de α-tricálcico (α-TCP) ou hidroxiapatita (HAp), a 10% em peso, foram formulados e comparados com AH Plus (AHP). Viabilidade celular foi avaliada por brometo de 3- (4,5-dimetil-tiazoil) -2,5-difenil-tetrazólio (MTT) e sulforodamina B (SRB). Cimentos foram implantados no tecido subcutâneo dos ratos e avaliados histologicamente. Bioatividade foi avaliada pela atividade da enzima fosfatase alcalina (ALP) e Alizarin Red (AR) utilizando células da papila apical (SCAPs) e pela deposição óssea, medida em cavidades cirúrgicas no fêmur de ratos preenchidos com AH Plus e α-TCP. Nos dois ensaios de viabilidade, HAp e AHP não apresentaram diferenças estatísticas, α-TCP apresentou menores resultados de viabilidade para o ensaio MTT (p <0,05). Resultados histológicos mostraram que houve uma diminuição do conteúdo inflamatório de acordo com os períodos, e o AHP foi o único grupo que apresentou células gigantes (período de 7 dias). A condensação das fibras colágenas aumentou conforme os períodos, sem diferenças entre os grupos. Houve aumento da atividade da ALP e deposição de nódulos mineralizados de acordo com os períodos. HAp e α-TCP apresentaram maiores valores para a atividade de ALP em 5 dias e em 5, 10 e 15 dias para AR, com diferença para o AHP (p <0,05). O α-TCP apresentou valores superiores aos 10 e 15 dias quando comparado ao HAp e AHP para AR (p <0,05). Aos 90 dias, α-TCP e controle (cavidade vazia) apresentaram maior deposição de tecido ósseo quando comparado ao AHP (p <0,05). α-TCP e HAp, presentes nos cimentos à base de metacrilato, apresentaram biocompatibilidade e potencial para serem utilizados como seladores endodônticos na prática clínica. Investigações adicionais são necessárias para obter informações sobre as propriedades físico-químicas dessas formulações de cimentos antes de sua implementação clínica.

Immediate laser-induced hemostasis in anticoagulated rats subjected to oral soft tissue surgery: a double-blind study

Abstract Given the growing trend towards medical indications for continuous use of anticoagulants, the number of patients on these medications continues to rise. The management of patients on oral anticoagulants requiring oral surgical procedures has aroused much controversy. Changes in an anticoagulation regimen are associated with an increased risk of thromboembolism. However, it seems logical and advantageous for the patients' health if surgery could be performed without any change to the anticoagulation therapy. In dentistry, high-power lasers have been poorly explored in this field. The hemostatic properties of high-power lasers could be helpful during oral soft tissue surgeries in anticoagulated patients. The aim of this study was to compare bleeding time in anticoagulated rats after lingual frenectomy performed with a scalpel or diode laser with bleeding time in healthy animals. Twenty-four male Wistar rats were assigned to four groups (n = 6): (CS) Control-Scalpel Surgery; (AS) Anticoagulated-Scalpel Surgery; (CL) Control-Laser (diode laser 810 nm/1.5 W) Surgery; and (AL) Anticoagulated-Laser Surgery (diode laser 810 nm/1.5 W). Warfarin administration was used to induce anticoagulation. Blood was blotted every 30 seconds with filter paper until bleeding stopped to verify bleeding time. Two blinded researchers performed the surgeries and collected the bleeding time data. Diode laser surgery led to complete hemostasis in rats during and after lingual frenectomy. Zero bleeding was assessed during surgeries and after diode laser surgeries in anticoagulated rats. Laser-induced hemostasis offered an alternative solution to the controversial issue of intraoperative and postoperative bleeding control in patients on anticoagulation therapy.

Cytotoxicity of substances leached from a root canal sealer based on mineral trioxide aggregate

Objetivo: Com base nas características biológicas e físico-químicas do agregado de trióxido mineral (MTA), este seria o material mais adequado para a obturação do canal radicular. No entanto, esse material apresenta baixo escoamento e, consequentemente, difícil manipulação. O MTA Fillapex (MTA-F) foi criado na tentativa de combinar as propriedades físico-químicas do cimento endodôntico com as propriedades biológicas do MTA. No entanto, os estudos sobre as características biológicas do MTA-F ainda são controversos. Dessa forma, este estudo teve como objetivo analisar in vitro a citotoxicidade do MTA-F. Materiais e Métodos: fi broblastos gengivais foram cultivados em Dulbecco’s modifi ed Eagle Medium (DMEM) e submetidos ao meio de cultura condicionado pelo MTA ou MTA-F. Esse meio condicionado continha substâncias liberadas pelos cimentos endodônticos. Células cultivadas em meio fresco serviram como controle positivo. A viabilidade celular foi avaliada por ensaio do MTT após 1, 3, 5 e 7 dias. Os dados obtidos foram comparados por análise de variância (ANOVA) seguida pelo teste de Tukey (p < 0,05). Resultados: As células submetidas ao meio condicionado pelo MTA apresentaram curva de crescimento celular semelhante à das células do grupo controle. Para o grupo MTA-F, não houve crescimento celular e foi observado um número de células viáveis signifi cativamente menor do que o dos demais grupos durante todo o experimento. Conclusão: Substâncias liberadas a partir de MTA-F não permitiram o crescimento celular, mostrando que esse cimento endodôntico à base de MTA é altamente citotóxico. A característica de biocompatibilidade do MTA pode ser perdida com o MTA-F e comprometer o sucesso do tratamento endodôntico.

Aim: Based on its biological and physicochemical characteristics, mineral trioxide aggregate (MTA) could be considered the most appropriate material for root canal obturation; nevertheless, handling of MTA is not easy. The MTA Fillapex (MTA-F) was created in an attempt to combine the physicochemical properties of a root canal sealer with the biological properties of MTA. However, the studies on the biological characteristics of MTA-F are still controversial. Thus, this study aimed to analyze the cytotoxicity of MTA-F. Materials and Methods: Cultured human gingival fi broblasts were grown in Dulbecco’s modifi ed Eagle Medium (DMEM) and submitted to a cell culture medium conditioned by MTA or MTA-F. The conditioned medium contained substances leached from the root canal sealers. Cells grown on a fresh medium served as a positive control. Cell viability was assessed by MTT assay at 1, 3, 5 and 7 days. Data was compared by ANOVA followed by Tukey’s test (p < 0.05). Results: Cells submitted to media conditioned by MTA presented a cell growth curve similar to that of the control cells. For the MTA-F group, cell growth was not observed and cell viability was signifi cantly lower than for the other groups during the entire experiment. Conclusion: Substances leached from MTA-F did not allow cell growth, indicating that this MTA-based root sealer is highly cytotoxic. The biocompatibility characteristic of MTA can be lost with MTA-F, and may compromise the endodontic treatment outcome.

Effect of laser phototherapy in the prevention and treatment of chemo-induced mucositis in hamsters

The aim of this study was to investigate the effect of laser phototherapy (LPT) in the prevention and/or treatment of oral mucositis induced by 5-fluorouracil (5-FU; Eurofarma, São Paulo, Brazil) in hamsters. Ninety-six hamsters were divided into four groups (n = 24): Control (no treatment); Preventive [LPT from day (D) D-5 to D+5]; Therapeutic (LPT from D+5 to D+15); and Combined (preventive plus therapeutic LPT from D-5 to D+15). The animals received an intraperitoneal injection of 5-FU on Days 0 and 2. The pouch mucosa was scratched on Days 3 and 4. The irradiation parameters were: indium-gallium-aluminum-phosphide (InGaAlP) diode laser (MM Optics, São Carlos, Brazil) (660 nm), beam area of 0.036 cm2, 40 mW, 1.11 W/cm2, 6.6 J/cm2, power density applied daily of 39.6 J/cm2, in punctual mode (six points and six seconds per point) and contact mode, one application per day. The animals were sacrificed on Days 0, 5, 10 and 15 (n = 6) and weighed, and the pouch mucosa was removed for histopathological analysis. Clinical and corresponding histological scores were compared using ANOVA and Tukey's test (p ≤0.05). Similar weight losses ranging from 5% to 10% occurred in all groups. The therapeutic group had significantly lower clinical and histological scores than the other groups at Day 10. This study showed that positive effects on oral mucositis management were obtained only when LPT was applied in the therapeutic protocol (from D+5 to D+15 after chemotherapy).

Análise "in vitro" de fraturas marginais em restauraçöes de amálgama em dentes decíduos / Analysis \"in vitro\" of marginal fractures on amalgam restorations in deciduous teeth

Os autores analisaram as fraturas das cristas marginais em restauraçöes de amálgama em dentes decíduos. Foram utilizados dentes decíduos esfoliados com restauraçöes tipo Classe II, coletados do Banco de Dentes Decíduos da Disciplina de Odontopediatria da Faculdade de Odontologia da Universidade de Säo Paulo. Deduziram que as cristas marginais näo säo restabelecidas corretamente