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Background/Aim. It has been demonstrated that lymphocytes, plasma cells, macrophages and neutrophil granulocytes represent the predominant cells of the inflammatory lesion of the dental granulomas. Other cells, such as mast cells, eosinophils, dendritic cells comprise minor, but functionally important cell populations. Most of the data considering cells that take part in these processes have been derived from immunohistological studies. This study was undertaken with the aim to determine the phenotype profile of inflammatory cells of dental granulomas using immunohistochemical method in order to study the differences of their quantitative properties and distribution between symptomatic and asymptomatic lesions. Methods. The material for the analysis originated from 42 individuals with clinic and radiographic diagnosis of chronic periapical lesions. The tissue was take either during the periradicular surgery, or tooth extraction. Cryostat tissue sections were stained using the alkaline phosphatase-antialkaline phosphatase assay (APAAP). This method is highly valid and sensitive using a panel of specific monoclonal antibodies: CD3, CD4, CD8, CD19, CD38, CD14, CD1a, CD83, CD80, CD86, CD45 and CD123. Results. The composition of the cell population revealed that there was no homogenous and site-specific pattern of the distribution of inflammatory cells. The results of our investigation revealed that the majority of inflammatory cells comprised lymphocytes and plasma cells, followed by subpopulations CD4+, CD8+ and CD14+ cells. Much lower in number were CD80+, CD86+ and CD83+ and CD1a+ cells. There were no statistically significant differences in mean values of inflammatory cells number between symtomatic and asymptomatic lesions, with the exception of CD86+ cells, the number of which was statistically higher in symptomatic lesions. Conclusion. Inflammatory infiltrate cells in dental granulomas are dominated by T- and Blymphocytes. It points out the complexity of immunopathogenic events in initiating and progressing of dental granulomas that involve mechanisms of both cellular and humoral immunity. Regarding the quantitative presence of immunocompetent cells in symptomatic and asymptomatic lesions no statistically significant difference was determined unless in mature dendritic cells present in symptomatic lesions. [ABSTRACT FROM AUTHOR]

Background/Aim. There are very few data about the effects of endogenous growth factors in vital pulp therapy, and still they are often controversial. The aim of the study was to evaluate the effects of platelet rich plasma (PRP) in conjugation with hydroxyapatite (HAP), as pulp capping materials, to root and periodontium formation. Methods. Eight young monkeys (Cercopithecus Aethiops) with permanent dentition and incomplete root formation were involved in this study. After pulpotomy, the pulp lesion was capped with calcium hydroxide (control), hydroxyapatite (experimental group I) or hydroxyapatite in conjugation with PRP (experimental group II). Six months later, the animals were sacrificed, the tissue was removed en block, and prepared for the histological analysis in a routine way. Results. The results of the histological analysis revealed that healing process was characterised by dentin bridge formation, maintained morphological and functional integrity of dental pulp and complete formation of dental root and surrounding periodontium. The inflammatory reaction was scored as mild to moderate, in almost all the samples in all groups, suggesting the biocompatibility of the used materials. Conclusion. Materials used in this study are convenient as capping agents, contributing maintaining the integrity of the pulp tissue and facilitating root and periodontium formation. According to histological data it could be suggested that hydroxyapatite in conjugation with endogenous growth factors, represents superior alternative to other materials used in this study. [ABSTRACT FROM AUTHOR]

Background/Aim. In dentistry, the concept of using inert m aterials f or t issue r epair h as b een replaced by the strategy to find bioactive materials which positively interact with human tissues. The aim of this study was to characterize the physicochemical properties of the commercially available calcium silicate and calcium carbonate-based dental cement, biodentine (Septodont, France). Methods. Material elucidation included the measurements of radiopacity, scanning electron microscopy and x-ray dispersive analyses, wettability, Fourier transform infrared spectroscopy, microindentation, micro- to nanoporosity, setting time, pH and calcium ion release. The cells (mouse bone marrow mesenchymal stem cells - BMSCs) were grown on biodentine surface in order to evaluate its behaviour under biological conditions. Results. The radiopacity of the cement (2.8 mmAl) was below ISO requirement for a root canal filling material. The cement was composed of fine powder with particles similar in size and shape, changing from oval to cubic after having been soaked in a simulated body fluid. Biodentine demonstrated good micromechanical properties and low porosity attributed to microporosity with the average pore size of 92 μm. Wettability (contact angle = 41°), calcium ion release (0.098 μg/cm²) and pH of storage solution (9.07) showed satisfactory characteristics. The BMSCa in intimate contact with cement particles remained viable, indicating biodentine good biocompatibility. Conclusion. Biodentine exhibits good mechanical and physicochemical characteristics, but possesses insufficient radiopacity. [ABSTRACT FROM AUTHOR]

Background/Aim. The materials used nowadays for bone replacement do not fully meet the requirements for complete regeneration, which is why new ones are being tested. Despite numerous attempts to improve bone tissue regeneration, no fulfilling material has been found yet. This study investigated the influence of poly-lactide-co-glycolide (PLGA) and polyethyleneimine (PEI) as coatings for hydroxyapatite (HAP) bone carriers on bone tissue regenerative potential in rabbits' calvarial defect. Methods. Calvarial defects measuring 6 mm in diameter were made in 19 skeletally mature rabbits. Defects were filled with one of the following materials: PLGA coated HAP (HAP + PLGA), PEI coated HAP (HAP + PEI), and bovine HAP - Bio-Oss® (positive control). Unfilled defects represented negative control. Histological analysis was performed in order to determine the inflammatory response of the host tissue. The formation of the new bone was evaluated using histomorphometric analysis. All analyses have been conducted in samples obtained 3, 6, and 9 weeks after implantation. Results. Three weeks post-implantation, a trend toward increased healing in the HAP + PLGA group compared to other investigated materials was noticed, with no statistically significant difference between the study groups (p > 0.05). However, after 6 and 9 weeks, significant healing was observed in favor of the HAP coated with PLGA compared to other groups (p < 0.05). Within this group, greater bone healing was observed compared to the HAP + PEI and Bio-Oss® groups. Conclusion. PLGA demonstrated greater coating potential compared to PEI with respect to osteogenesis improvement in bone reconstructive surgery. [ABSTRACT FROM AUTHOR]

Background. Different materials are used to prevent the resorption of alveolar bone. The aim of this report was to show the radiographical and histological results prior to implant insertion, when a deproteinized bovine bone mineral (BioOss) and calcium-sulphate were placed into the extraction socket immediatelly after the tooth removal. Case report. A 22-year-old woman was scheduled for the removal of the second lower molar when the extraction socket was filled with BioOss covered with calcium-sulphate as a resorbable membrane. Primary closure of the surgical site was performed. Radiography was done 4 and 12 months later. One year after the surgery, when the implant was inserted, a biopsy of the new regenerated bone was obtained for the histological evaluation. The lamellar bone was evident using both materials. The resorption of BioOss was slow and the connective tissue was observed. Conclusion. Both materials had biocompatible and oseoconductive properties. One year after the grafting procedure, we observed the lamellar bone and partial resorption of BioOss, while calciumsulphate showed no significant effect as a resorbable membrane. [ABSTRACT FROM AUTHOR]