With the implementation of bone substitute materials, regeneration strategies have inevitably evolved over the years. Histomorphometry is the optimal means of quantitative evaluation of bone structure and morphology. This systematic review focuses on determining study models, staining methods and histomorphometric parameters used for bone regeneration research on non-decalcified plastic-embedded specimens over the last 10 years. After being subjected to the inclusion and exclusion criteria, 118 studies were included in this review. The results establish the most commonly selected animal model is rat, followed by rabbit, sheep and dog. Strong preference for staining samples with toluidine blue was noted. With regard to histomorphometric parameters, terms related to bone were most frequently assessed, amounting to almost half of recorded parameters. New bone formation was the main descriptor of this category. Residual bone graft and non-bone tissue parameters were also often evaluated. With regard to dynamic histomorphometry, mineral apposition rate (MAR) was the parameter of choice for most researchers, with calcein green being the preferred dye for fluorochrome labelling. An overview of the contemporary literature, as well as weaknesses in the current research protocols have been discussed.

In recent years, there has been a sharp increase in the number of chronic periodontal diseases. The problem of their widespread distribution and the need for their treatment is one of the priorities of modern dentistry. Periodontal bone defects are the result of chronic periodontitis if timely measures are not taken to stop the inflammatory process. The goal of periodontal treatment is to remove all deposits of supra- and subgingival dental plaque and calculus (containing periodontopathogens) and their plaque-retentive factors and to promote complete regeneration of the tooth-supporting structures lost up to that point. Until now, autogenous, platelet-rich plasma has been widely used in various fields of medicine. Because of the equivalent results obtained and the lower cost, in dentistry, autogenous platelet-rich plasma is increasingly the preferred material over others that have proven to be reliable over time. Summarizing the results of various authors who used autogenous platelet-rich plasma alone or in combination with other materials for the purpose of regeneration of vertical bone defects, it is clear that PRP significantly accelerates the restorative and regenerative processes in the periodontium.

Context and objective The main goal of periodontal therapy is to remove periodontopathogenic microorganisms and regenerate destructured periodontal tissues. Advances in biomaterials have improved the results of regenerative procedures. However, there is limited data available to determine the best material for vertical bone deformities treated with regenerative treatment. Studies on autogenous platelet-rich plasma (PRP) have been conducted, but it is often combined with other biomaterials. The objective of this study is to examine the exact efficacy of solely administering autogenous PRP in regenerative therapy of vertical bone defects. Materials and methods The study was conducted from August 2022 to July 2023 at the Faculty of Dental Medicine, Medical University Varna, BGR, using the University Medical and Dental Center as its base. It includes 12 cases with bipartite, tripartite, or a combination of the listed vertical bone defects. Participating patients met the following criteria: signed informed consent; age between 18 and 65 years; individuals in good health without diagnosed systemic disease, and adequate dental care. The clinical parameters investigated and recorded immediately before regenerative therapy with autogenous PRP and six months after the surgical intervention were probing depth, margo gingivalis level, clinical attachment level, and cone beam computed tomography (CBCT)-indicators A (the distance from the cemento-enamel junction to the bottom of the bone defect), B (the distance from the cemento-enamel junction to the apex of the bone defect), and C (the width of the defect). The results obtained from the measurements immediately before the regenerative therapy with PRP and six months after the surgical intervention were compared and analyzed. Results and conclusions The clinical outcomes for vertical bone defects at the six-month mark following the PRP therapy showed an average 3.83 mm reduction in probing depth, an average 0.08 mm coronal migration of the gingival margin, and an average 3.92 mm gain of the clinical level of attachment. The CBCT showed bone filling, which is supported by the average decrease for points A, B, and C of 1.69 mm, 0.51 mm, and 0.36 mm, respectively. The study's findings primarily illustrate the strong potential of autogenous PRP as an independently applicable substance for regeneration therapy in periodontology.

Background and objective Enamel matrix derivatives (EMD) are biomaterials extracted from porcine dental germs. They consist of amelogenins (90%), ameloblastine, enamelin, and amelotin. New evidence has shown that all these proteins can be absorbed onto hydroxyapatite crystals and collagen fibers on the root surface of teeth and initiate regeneration of root cementum as well as stimulate periodontal cell proliferation. Currently, the most preferred method of periodontal regenerative therapy in clinical dental practice involves EMD, thanks to its facilitated surgical protocol and the many postoperative complications associated with guided tissue regeneration. There is scarce data regarding when the first and earliest signs of healing occur after the application of this method. Hence, this study focused on the evaluation and analysis of clinical outcomes and cone-beam CT (CBCT) results at six months after the application of the EMD technique. It aimed to evaluate the efficacy of regenerative therapy with EMD in vertical bone defects six months post-surgical intervention. Material and methods The study was conducted between August 2022 and July 2023 in the Faculty of Dental Medicine, the Medical University - Varna, using the University Medical-Dental Center as a base. The study included 12 cases characterized by bilateral, trilateral, or a combination of the mentioned vertical bone defects. The participants were aged between 31 and 57 years, of both genders, with satisfactory personal oral hygiene. They were in good general condition with no established systemic diseases and gave prior written informed consent. Between the sixth and eighth weeks after the hygiene phase was completed, the patients were re-evaluated, a new periodontal status was recorded, and a CBCT examination was ordered. Three clinical (probing pocket depth, gingival margin level, and clinical attachment level) and three radiographic parameters (A, B, and C) were evaluated in areas of vertical bone defect. Six months after the regenerative therapy using EMD, the same parameters were again recorded in all patients. Finally, after statistical processing of the results, an analysis of the data was performed regarding the early effectiveness of EMD application in regenerative therapy of vertical bone defects. Results The clinical results observed at the six-month mark following regenerative therapy using EMD in vertical bone defects indicated an average reduction in probing depth of 4.50 mm, an average apical migration of the gingival margin by 0.5 mm, and an average clinical attachment level of 4.00 mm. Bone filling was noted on the CBCT, corroborated by the following parameters: A - an average decrease of 1.51 mm; B - an average decrease of 0.50 mm; and C - an average decrease of 0.24 mm. Conclusions The results of our study confirm the remarkable effectiveness of EMD as a regenerative biomaterial. Furthermore, both clinical and CBCT studies demonstrated a very good healing process at an extremely early stage after the surgical intervention.

Context The underlying principle of guided tissue regeneration (GTR) lies in the use of barrier membranes. Their role is key to this method, as they inhibit the rapid growth of epithelial and connective tissue cells, thus isolating the infrabony defects (IBDs) and ensuring the regeneration of slower-growing periodontal structures. The main disadvantages of resorbable membranes are related to their limited time of action and the need to use them in two layers, which increases the chance of a postoperative complication, i.e., the dehiscence of the barrier membrane. In cases where barrier membranes are used alone, there is a risk of soft tissue “collapse” into the IBDs and disruption of the blood clot zone. This is why they are more commonly used in combination with bone repair material. However, when relatively smaller periodontal ​​​​​​IBDs are present, barrier membranes can be used alone. It is such IBDs that are included in the present study that are relatively narrow and not as deep. The technique of GTR, with the sole application of a resorbable collagen membrane, was used. Clinical and radiographic results were evaluated and analyzed at the earliest possible stage after the intervention, which was the sixth month. In this way, we demonstrated the remarkable regenerative capabilities at an extremely early stage of the increasingly neglected GTR technique with the sole application of a barrier membrane. Aim Investigation into the efficacy of GTR for vertical IBDs utilizing solely applied barrier membranes assessed six months post-surgery. Material and methods The research was carried out from August 2022 to July 2023 at the Medical University Varna, Varna, Bulgaria, specifically within the Faculty of Dental Medicine, utilizing the University Medical and Dental Center as its basis. The study encompasses 12 cases featuring two-wall, tri-wall, or a combination of the specified vertical IBDs. Following Ramfjord’s treatment sequence, an up-to-date periodontal status was recorded at the re-evaluation stage after the hygiene phase, and a cone beam computed tomography (CBCT) examination was ordered in the areas with vertical IBDs. Three clinical (probing pocket depth, gingival margin level, and clinical attachment level) and three radiographic parameters (A, B, and C) were evaluated immediately before the future surgical intervention. Six months after the GTR with the sole application of a barrier collagen membrane, the same parameters studied at an earlier stage were recorded on all patients. Results The clinical outcomes observed at six months post-GTR utilizing a barrier membrane in vertical IBDs indicated an average reduction in probing depth of 4.17 mm, an average apical migration of the gingival margin of 0.33 mm, and an average gain of clinical attachment level of 3.83 mm. Bone filling is evident on the CBCT, corroborated by the following measurements: (A) an average reduction of 1.68 mm, (B) an average reduction of 0.50 mm, and (C) an average reduction of 0.11 mm. The study’s impressive results are largely due to the relatively small number of cases included, requiring further improvement to confirm the method’s effectiveness. Conclusions The study confirms the potential of the membrane technique, although the extent of the healing process is assessed at an extremely early stage. It can be safely concluded that it is not always necessary to place bone repair material under the barrier membrane to obtain good healing results.

Application of autogenous platelet-rich plasma in periodontology