Effect of alpha-humulene incorporation on the properties of experimental light-cured periodontal dressings

Abstract The objective of this study was to formulate an experimental light-cured periodontal dressing containing alpha-humulene and to compare its physical, antimicrobial, and cytotoxicity properties with commercial gold standards (Barricaid® and Periobond®). Two periodontal dressing formulations were developed (a and b). The formulations were divided into 5 groups according to the alpha-humulene concentration as follows: Ea - control group, Ea1 - 1%, Ea5 - 5%, Ea10 - 10%, and Ea20 - 20%; Eb - control group, Eb1 - 1%, Eb5 - 5%, Eb10 - 10%, and Eb20 - 20%. Materials characterization was performed using the degree of conversion, cohesive strength, sorption, and solubility assays. Antimicrobial assay was performed using the modified direct contact test against E. faecalis and S. aureus. Cytotoxicity was assessed by the cell viability experiment using L929 fibroblasts. In general, the cohesive strength values of materials decreased as the alpha-humulene concentration increased. All the experimental dressings showed antimicrobial activity against both bacteria tested. Cell viability results for the Ea, Ea1, Eb, and Eb1 groups showed moderate cytotoxic effect. The formulations containing alpha-humulene showed similar behavior to the commercial references. Thus, formulations containing alpha-humulene have potential to be used as periodontal dressing.

Biological and mechanical characterization of commercial and experimental periodontal surgical dressings

Abstract The objective of this study was to evaluate the biocompatibility and mechanical properties of two commercially available and one experimental periodontal dressing materials. The cytotoxicity of Periobond ® , Barricaid ® and one experimental periodontal dressing based on Exothane ® 8 monomer was tested on 3T3/NIH mouse fibroblast. Genotoxicity was assessed by micronuclei formation, and cell alterations were analyzed using light microscopy. Both biological assays were performed using the eluate obtained from specimens after 24, 72, or 168 hours of incubation. Mechanical characterization was assessed through the ultimate tensile strength and the water sorption and solubility tests. The significance level of α = 0.05 was used for all statistical analyses. All the materials promoted a cell viability lower than 60% in all evaluated times. In general, the cell viability was significantly reduced after 72 and 168h of specimens' incubation. Considering the factor material, there were not statistical differences in the cell viability (p = 0.156). The genotoxicity was not statistically significant among the groups in the different periods of time (p > 0.05). Differences in the ultimate tensile strength values were not statistically significant different among the groups (p = 0.125). Periobond ® showed the higher water sorption values (p < 0.001). Regarding solubility, there were no statistical differences between the groups (p = 0.098). All the periodontal dressing materials evaluated in this study exerted a cytotoxic effect against mouse fibroblasts, and their toxicity became more evident over time. Among the materials evaluated, the experimental light-cure type has shown overall similar properties to the commercial references.

Efectividad del Tisuacryl como apósito periodontal en técnicas quirúrgicas / Effectiveness of Tisuacryl as a periodontal dressing in surgical techniques

RESUMEN Introducción: el Tisuacryl es un biomaterial de gran efectividad como apósito periodontal en papilectomías, gingivectomías y gingivoplastias. Objetivo: determinar la efectividad del Tisuacryl con respecto al cemento quirúrgico o Quirucem, usados como apósito periodontal en cirugías periodontales. Métodos: estudio observacional analítico de casos y controles en 60 pacientes con diagnóstico de gingivitis crónica fibrosa y fibroedematosa desde septiembre de 2016 a junio de 2017. Se realizó examen físico, confección de historia clínica de periodoncia, tratamiento periodontal y selección de pacientes con necesidad de tratamiento quirúrgico. Se utilizaron medidas de resúmenes para variables cualitativas como el porcentaje y para variables cuantitativas como la media y la desviación estándar. Se empleó el test estadístico prueba de Chi cuadrado con nivel de significación de &= 0.05 para la comparación de los grupos con diferentes modalidades de tratamiento. Resultados: el total de los pacientes tratados con Tisuacryl expresaron comodidad con el uso de este y no se produjo acúmulo de placa dentobacteriana. Solo el 30 % presentó enrojecimiento a los siete días, pero a los 15 se constató cicatrización total de la herida. Con Quirucem existieron todos los síntomas y signos estudiados y en todos los casos el enrojecimiento; más de la mitad presentó incomodidad en la evolución y el 40 % de los casos a los 15 días continuaban sin cicatrizar totalmente. Conclusiones: el Tisuacryl resultó más efectivo con respecto al Quirucem considerando el menor tiempo de cicatrización, mayor comodidad y estética en los pacientes.

ABSTRACT Introduction: Tisuacryl is a highly effective biomaterial as a periodontal dressing in papillectomies, gingivectomies and gingivoplasties. Objective: to determine the effectiveness of Tisuacryl with respect to surgical cement or Quirucem, used as a periodontal dressing in periodontal surgeries. Methods: observational analytical study of cases and controls in 60 patients with the diagnosis of chronic fibrous and fibro-edematous gingivitis from September 2016 to June 2017. Physical examination, periodontal history, periodontal treatment and selection of patients in need of surgical treatment were performed. Summary measures were used for qualitative variables, such as percentage and for quantitative variables such as mean and standard deviation. The chi-square statistical test with a significance level of &= 0.05 was used to compare the groups with different treatment modalities. Results: all patients treated with Tisuacryl expressed comfort with its use and no accumulation of dentobacterial plaque occurred. Only 30 % had redness at seven days, but at 15 days the wound was completely healed. With Quirucem all the symptoms and signs studied were present along with redness in all cases; more than the half of patients complained of discomfort during evolution and 40 % of the cases at 15 days remained totally unhealed. Conclusions: Tisuacryl was more effective than Quirucem considering the shorter time of cicatrization, greater comfort and better aesthetics results in patients.

Evaluation of tissue response to periodontal dressings: histological study in tooth sockets of rats

Although the use of periodontal dressings is currently limited, there are some indications for their use. Selection of any material that will have direct contact with live tissues, such as periodontal dressings, should be careful in order to allow surgical wound healing. The aim of this study was to evaluate the intensity of inflammatory response and bone formation in tooth sockets of rats after implantation of three periodontal dressings. After removal of the right maxillary incisors of 84 male rats, each tooth socket received implantation of a polyethylene tube, 63 of which were filled with non-eugenol periodontal dressing and the remaining 21 tubes remained empty (control group). Histological evaluation assessed the intensity of inflammatory response and presence and location of bone tissue formation at postoperative periods of 7, 14 and 28 days. Statistical analysis was performed by the Kruskal-Wallis test at 5% significance level. Regarding the inflammatory infiltrate, at 28 days, there was statistically significant difference between one of periodontal dressings and control group (p<0.05). Analysis of postoperative periods, showed that the control group presented statistically significant reduction in the inflammatory infiltrate comparing the 14- and 28-day periods (p<0.05). Regarding bone tissue formation, there was difference in control group between the 7- and 28-day periods (p<0.05). Within the experimental conditions, it may be concluded that no differences were found in the inflammatory response among the groups at 7 and 14 days and that Voco pac™ dressing induced a more intensive inflammatory reaction at 28 days.