Influence of photoactivation on tissue response to different dyes used in photodynamic therapy and laser ablation therapy.

Laser ablation therapy (LA) uses Indocyanine Green dye (ICG) which efficiently absorbs laser energy and the increased temperature results in an instantaneous flame that chars tissue and microbes. Photodynamic therapy (PDT) uses different dyes that are activated by light to kill bacteria. This study evaluated the biocompatibility of the dye Curcumin (CUR), Methylene Blue (MB), and Indocyanine Green (ICG) before and after laser activation (ACT). Polyethylene tubes containing one of the dyes were implanted in the subcutaneous tissue of 32 rats (4 tubes per rat) which were divided into 8 groups: C - control (saline solution); C + ACT (Red Laser 660 nm); CUR; CUR + ACT (480 nm blue LED); MB; MB + ACT (Red Laser 660 nm); ICG; ICG + ACT (810 nm Infrared Laser). After 7 and 30 days (n = 8/time), the rats were euthanized and the tubes with the surrounding tissue were removed and processed for histological analysis of inflammation using H&E stain, and collagen fiber maturation using picrosirius red (PSR). A two-way analysis of variance statistical test was applied (p < 0.05). At 7 days, regardless of laser activation, the CUR group showed a greater inflammatory infiltrate compared to the ICG and control groups, and the MB group had a greater inflammation only in relation to the control (p < 0.05). At 30 days, CUR and MB groups showed a greater inflammatory infiltrate than the control (p < 0.05). ICG group was equal to the control in both periods, regardless of the laser activation (p > 0.05). Laser activation induced the proliferation of collagen immature fibers at 7 days, regardless of the dye (p < 0.05). The CUR group showed a lower percentage of immature and mature fibers at 7 days, compared to ICG and control (p < 0.05) and, at 30 days, compared to control (p < 0.05). Regardless of laser activation, the ICG showed the results of collagen maturation closest to the control (p > 0.05). It was concluded that all dyes are biocompatible and that laser activation did not interfere with biocompatibility. In addition, the maturity of collagen was adequate before and after the laser activation. These results demonstrate that the clinical use of dyes is safe even when activated with a laser.

Interleukin-6, tumor necrosis factor-α, and CD5 immunolabeling of new experimental endodontic sealer and repair material.

The aim of this study was to evaluate the biocompatibility and immunoinflammatory response of the Sealepox and Sealepox-RP, based on interleukin (IL)-6, tumor necrosis factor (TNF)-α, and CD5 immunolabelling. The ProRoot MTA (PRMTA) was used for comparison. Polyethylene tubes (1.0-mm internal, 1.6-mm external diameter, and 10.0-mm length; ISO 10993) with or without (control) materials were randomly implanted in the dorsum of 35 rats (4 per rat). After 7, 15, 30, 60, and 90 days (n = 7), the tubes were removed for histological and immunohistochemical analysis. The Kruskal-Wallis and Dunn's test for non-parametric data and, ANOVA and Tukey test for parametric data were used (P < 0.05). Hematoxylin and eosin staining revealed that the concentration of inflammatory cells decreased over time with no differences between groups in all periods (P > 0.05). Regarding IL-6 immunostaining, there was no difference at 7 days (P > 0.05); all groups decreased over time, being faster for the PRMTA group and also, with no differences between groups in the last period (P > 0.05). For TNF-α, at 7 days there was no difference between groups (P > 0.05); there was an increase at 15 days for PRMTA and, at 30 and 60 days, for PRMTA and Sealepox compared to the control (P < 0.05). At 90 days, Sealepox RP showed the lowest immunostaining being similar to the control (P > 0.05). Regarding CD5 cells, at 7 days, there was high immunostaining for PRMTA compared to the control (P < 0.05); and significant reduction over time with difference for all groups at 30 and 60 days. (P < 0.05); Sealepox was similar to the control in all periods (P > 0.05). Sealepox RP showed the highest immunostaining at 15 days, being different from the control and PRMTA (P < 0.05); in the other periods it was similar to the control (P > 0.05). It can be concluded that Sealepox and Sealepox-RP were biocompatible and demonstrated similar immunoinflammatory response regarding IL-6, TNF-α, and CD5 compared to PRMTA.

Melatonin as an adjunctive treatment on dental procedures: A systematic review.

The systematic review tried to answer the following question: Does the melatonin administered systemically or topically ameliorate patients involved with oral health conditions or dental procedures? The systematic review has been registered in the PROSPERO (2021CRD42021095959). Eligibility criteria included only randomized controlled clinical trials (RCTs) with at least 10 participants that compared patients that received melatonin as a treatment before and/or after their oral intervention topically or systemically, with control patients. A search was performed in PubMed/MEDLINE, Web of Science, Cochrane Library, and Academic Google databases for articles up to February 2021. The Cochrane risk-of-bias tool for randomized clinical trials was used and revealed that the studies included presented low risk of bias for the majority of criteria assessed. It was selected 25 articles, of which only six did not demonstrate positive effects and three presented null effects with the use of melatonin. Melatonin has improved the inflammatory response in periodontal disease, dental surgeries, and mucositis of head and neck oncologic irradiated patients. In addition, it showed anxiolytic potential in patients that were submitted to dental procedures. In conclusion, melatonin favored the treatment of oral changes when used topically and systemically.

Antibioticoterapia sistêmica influencia na intensidade do infiltrado inflamatório e na reabsorção óssea da periodontite apical induzida / Systemic antibiotic therapy influences the intensity of the inflammatory infiltrate and bone resorption of induced apical periodontitis

Introdução: O objetivo deste trabalho foi investigar a influência da antibioticoterapia sistêmica no desenvolvimento e na progressão da periodontite apical em ratos Wistar. Material e Métodos: Foram utilizados 56 ratos distribuídos aleatoriamente em 7 grupos experimentais (n=8): Grupo C - controle; Grupo GEN ­ ratos tratados com Gentamicina (10mg/Kg, uma vez ao dia); Grupo AC ­ ratos tratados com Amoxicilina (100mg/Kg, uma vez ao dia); Grupo MZ ­ ratos tratados com Metronidazol (40mg/Kg, uma vez ao dia); Grupo AMP ­ ratos tratados com Ampicilina (100mg/Kg, uma vez ao dia); Grupo AC+XL ­ ratos tratados com Amoxicilina + Clavulanato de Potássio (100mg/kg, uma vez ao dia) e Grupo CLI ­ ratos tratados com Clindamicina (60mg/kg, uma vez ao dia). A periodontite apical foi induzida por meio da exposição pulpar do primeiro molar inferior do lado esquerdo. A antibióticoterapia foi iniciada no mesmo dia da exposição pulpar e teve duração de 15 dias. Após este período os animais foram sacrificados, as mandíbulas coletadas e processadas para análise histológica e histométrica em coloração de Hematoxilina e Eosina, análise das fibras colágenas pela coloração de Picrosirius red e análise bacteriológica por Brown-Brenn. Testes estatísticos foram aplicados (p< 0,05). Resultados: O grupo AC+XL apresentou menor intensidade do infiltrado inflamatório e menor reabsorção óssea periapical em relação ao grupo controle (p< 0.05). Quanto à maturação do colágeno o grupo AC+XL apresentou menor quantidade de fibras maduras e maior quantidade de fibras imaturas, comparado a todos os grupos (p< 0,05). Os grupos AC e AC+XL apresentaram menor extensão da contaminação bacteriana em relação ao controle (p< 0,05). Conclusão: A amoxicilina associada ao ácido clavulânico influencia o desenvolvimento e a progressão da periodontite apical induzida, reduzindo a intensidade do infiltrado inflamatório, maturação do colágeno e reabsorção óssea periapical, assim como a contaminação bacteriana no sistema de canais radiculares(AU)

Introduction: The aim of this work was to investigate the influence of systemic antibiotic therapy on the development and progression of apical periodontitis in Wistar rats. Material and Methods: 56 rats were randomly distributed in 7 experimental groups (n = 8): Group C - control; GEN group - rats treated with gentamicin (10mg / Kg, once daily); AC Group - rats treated with Amoxicillin (100mg / Kg, once a day); MZ group - rats treated with Metronidazole (40mg / Kg, once a day); AMP group - treated with Ampicillin (100mg / Kg, once a day); AM + C Group - rats treated with Amoxicillin + Potassium Clavulanate (100mg / kg, once a day) and CLI Group - rats treated with Clindamycin (60mg / kg, once a day). Apical periodontitis was induced through pulp exposure of the lower left first molar. Antibiotic therapy was given on the same day of pulp exposure and lasted for 15 days. After this period, the animals were sacrificed, with jaws collected and processed for histological and histometric analysis using Hematoxylin and Eosin staining, collagen fiber analysis using Picrosirius red staining and bacteriological analysis using Brown-Brenn. Statistical tests were conceptualized (p < 0.05). Results: The AC+XL group showed lower intensity of inflammatory infiltrate and lower periapical bone resorption compared to the control group (p < 0.05). As for collagen maturation, the AC+XL group had a smaller amount of mature fibers and a greater amount of immature fibers, compared to all groups (p < 0.05). The AC and AC+XL groups showed a smaller extent of bacterial contamination compared to the control (p< 0.05). Conclusion: Amoxicillin associated with clavulanic acid influences the development and progression of induced apical periodontitis in Wistar rats, causing the intensity of the inflammatory infiltrate, collagen maturation and periapical bone resorption, as well as bacterial contamination in the root canal system(AU)