Evaluation of Bone Repair Using a New Biphasic Synthetic Bioceramic (Plenum® Osshp) in Critical Calvaria Defect in Rats.

(1) Background: Biphasic bioceramics are synthetic bone substitutes that provide greater safety and better predictability in guided bone regeneration. This study aimed to evaluate the bone repair process using a new biphasic bioceramic of synthetic origin (Plenum® Osshp-70HA: 30ß-TCP) in critical calvarial defects. (2) Methods: seventy-four defects were created in rat calvaria and divided into two groups-Plenum® Osshp (PO), right side, and Straumann® BoneCeramic™ (BC), left side. Euthanasia was performed at 7, 15, 30, and 60 days after surgery. (3) Results: Lower gene expression was observed for runt-related transcription factor 2 (RUNX2) and vascular endothelial growth factor (VEGF) and higher expression for Integrin Binding Sialoprotein (IBSP). The results correlated with moderate immunolabeling for osteocalcin (OCN) and slight immunolabeling for osteopontin (OPN) in the PO group. Histometry showed a greater amount of biomaterial remaining in the PO group at 60 days. The microtomographic analysis showed a lower density of bone connectivity and a greater thickness of the trabeculae for the remnants of the PO group. (4) Conclusions: the Plenum® Osshp showed no differences compared to BoneCeramic™ and is therefore considered an effective option as a synthetic bone substitute in bone regeneration.

Polydioxanone Membrane Compared with Collagen Membrane for Bone Regeneration.

Guided bone regeneration (GBR) is an approach that induces osteopromotion through the regenerative membranes. These barriers exhibit bioactive behavior and mechanical function. Polydioxanone is a synthetic option, already used in medicine and dentistry, with good results in bone regeneration. This study aimed to evaluate bone repair in critical defects in rat calvaria using a polydioxanone membrane (Plenum® Guide) compared with a commercially available collagen-based membrane (Bio-Gide®). The bone defects were filled with Plenum® Osshp, a synthetic bone graft, hydroxyapatite:ß-tricalcium phosphate, 70:30%, Group PG (Plenum® Guide + Plenum® Osshp), and Group BG (Geistlich Bio-Gide® + Plenum® Osshp). The specimens were submitted to immunohistochemical (RUNX2 and OPN), gene expression (RUNX2, IBSP, and VEGF), histometric, and microtomography analyses after 07, 15, 30, and 60 days postoperative. PG group showed greater immunolabeling area for RUNX2 and OPN, higher gene expression of VEGF (3.15 ± 0.85), and IBSP (24.9 ± 0.59). However, there was no statistical difference between groups in the histometric analysis regarding the percentage of connective tissue PG (0.83 ± 0.45), BG (0.70 ± 0.34), neoformed bone PG (0.60 ± 0.4), BG (0.65 ± 0.51), and remaining biomaterial PG (0.84 ± 0.31), BG (0.91 ± 0.33). In addition, there was no statistical difference between groups by micro-CT analysis. The absorbable-synthetic membrane, Plenum® Guide, is an effective membrane for guided bone regeneration.

Titanium Mesh Exposure After Bone Grafting: Treatment Approaches-A Systematic Review.

Study Design: A systematic review according to PRISMA statement has been designed to answer the preliminary question: "In titanium mesh exposures, is there a treatment alternative which leads to an increased graft maintenance?" and fill the PICO assessment out. Objective: To review studies published in the past 20 years (1999-2019) in which mesh exposure has occurred, detecting the suitable approaches to treat exposure allowing the graft maintenance. Methods: Initial search on PUBMED, SCOPUS, and COCHRANE databases resulted in 777 articles, and hand-searching identified 6 articles. After removing duplicates and unrelated articles, eligibility criteria were applied, and 31 studies were selected (randomized clinical trials, retrospective/prospective clinical trials, and case series). Results: A total of 677 surgical sites and 225 cases of mesh exposure were identified. Eleven treatments have been identified. Chlorhexidine was the primary approach in 46% of cases, followed by oral hygiene instructions and follow-up with 22.5% of occurrences. In 21% of clinical situations, titanium mesh removal was the treatment of choice, associated with other measures (i.e., antibiotic prescription). There seems to be a consensus in cases of infection. When this complication was associated with tissue dehiscence, the primary treatment was mesh removal. The same does not occur when the site needs to be cleaned for long-term periods. Conclusion: In 2 decades of use of titanium meshes, the available treatments do not seem to have evolved, and there is not enough data to establish a guideline.

Autogenous Dental Transplantation in a Patient Undergoing Class III Dento-Facial Deformity.

Dental transplantation is an alternative for rehabilitation with a high success rate. This article presents a clinical case of autogenous dental transplantation in a 17-year-old male patient undergoing treatment for Class III dento-facial deformity. After 32 months followup, low-cost rehabilitation was possible, and without prejudice to ortho-surgical treatment.

Le Fort I Down-Fracture for Management of Midface Tumors.

OBJECTIVE: To perform an integrative review associating current literature with a clinical series regarding the use of Le Fort I osteotomy for the removal of tumors located in the midface and central region of the skull base. METHODS: A systematic review was performed through the PubMed, SCOPUS, and Cochrane databases. In addition, 4 different patients operated using the above-cited technique are described in this study. RESULTS: Initially, 123 articles were found. After the removal of duplicates, and title and abstract reading, 27 articles were selected for data extraction. The Le Fort I surgical approach of tumors was performed in 183 patients. CONCLUSION: The Le Fort I surgical approach allows lesion exeresis with good visualization, low rates of recurrences and complications, and without aesthetic compromises for the patient.

Expressão imuno-histoquímica da Axina1, GSK3 ß, APC e via Wnt1 nos ameloblastomas / Expression immunohistochemistry of Axina1, GSK3 ß, APC e Wnt1 signaling in ameloblastomas

Os ameloblastomas são tumores odontogênicos, de origem epitelial, que demonstra crescimento lento e comportamento invasivo e altamente recidivante. No entanto os mecanismos moleculares e as vias de sinalização celulares envolvidas na progressão desse tumor não estão claros. Estudos relatados na literatura indicam que aberrações nas vias de sinalização similares as encontradas durante o desenvolvimento dentário, incluindo a via Wnt1 e as proteínas GSK3 ß, APC e Axina1, que formam o complexo de degradação da ß-catenina podem estar alteradas nos ameloblastomas, levando a proliferação e progressão tumoral. O objetivo deste trabalho foi analisar a relação da expressão das proteínas Wnt1, GSK3 ß, APC e Axina1 com a proliferação tumoral dos ameloblastomas por meio de reações de imuno-histoquímicas. Para este estudo foram selecionados 40 casos com o diagnóstico de ameloblastoma, pertencentes aos arquivos do Serviço de Patologia da Disciplina de Patologia Bucal da FOUSP e utilizada a técnica imunohistoquimica da estreptavidina-biotina em blocos parafinados destes casos selecionados. Nos resultados foram observados marcações positivas para a proteína Wnt1 em 25 (62,5%) casos, Axina1 em 23(57,5%), APC de 26(65%) casos e GSK3 ß em 34(85%) casos.

Ameloblastomas is an odontogenic tumors of epithelial origin, which shows slow-growing, highly invasive and recurrent behavior. Nevertheles the molecular mechanisms and cellular signaling pathways involved in the progression of this tumour are not yet clear. Reported studies in leterature indicates that aberrations in signaling pathways similar to those found during tooth development, including Wnt1 and GSK3 ß pathways, APC and Axin1 proteins which form the ß-catenin degradation complex may be altered in ameloblastoma, leading to proliferation and tumour progression. The aim of this study was to analyze the relationship between the expression of Wnt1, GSK3 ß, APC and Axin1 proteins with the tumour proliferation in ameloblastomas by immunohistochemical reactions. For this study, 40 cases were selected with the diagnosis of ameloblastoma, from the Oral Pathology department archives, Dental School, University of São Paulo and the immunohistochemistry technique of streptavidin-biotin in paraffin blocks of these selected cases was perfomed. Positive results to the Wnt protein were observed in 25 (62.5%) cases, Axina1 in 23 (57.5%), APC of 26 (65%) cases and GSK3 ß in 34 (85%) cases.

Reprodutibilidade de medidas antropométricas estáticas de graduandos de odontologia e de mochos odontológicos / Reproducibility of static anthropometric measurements of undergraduate dental students and dental stools

Objetivo: Avaliar a reprodutibilidade intra-examinador de medidas antropométricas estáticas de graduandos do curso de Odontologia, bem como características e medidas de regulagem de mochos odontológicos por eles utilizados. Método: Foram avaliados 40 voluntários e 6 tipos de mochos. Para tomada das medidas antropométicas, os equipamentos utilizados foram cadeira de escritório adaptada, trena flexível com duas hastes adaptadas, dispositivo metálico com ângulo central de 90º, barbante, prancha de madeira retangular medindo 35 x 24 cm, fita isolante e fita crepe. Para padronização do posicionamento da cadeira de escritório adaptada e dos pés dos voluntários foram feitas marcações com fita crepe e isolante no chão. Um fio de barbante foi amarrado na região da cintura de cada voluntário com o objetivo de demarcar a área correspondente à região renal, possibilitando a tomada da medida assento-região renal. As medidas antropométricas observadas foram altura, altura tronco-encefálica, medida sacro-poplítea, largura do quadril, altura poplítea e altura assento-região renal. As características do mocho avaliadas em relação ao assento foram profundidade, largura horizontal e altura mínima/máxima. Em relação ao encosto foram avaliados o ajuste mínimo/máximo de altura. As medidas antropométricas e medidas dos mochos odontológicos foram tomadas por um examinador, em dois momentos distintos, com o intervalo de uma semana entre as avaliações. Para estimar a reprodutibilidade intra-examinador foi utilizado o coeficiente de correlação intra-classe (p). Resultados: Verificou-se um excelente resultado de reprodutibilidade para todas as medidas antropométricas tomadas (p=0,99) bem como para os mochos odontológicos avaliados (p=0,99). Conclusão: A tomada de medidas antropométricas e dos mochos odontológicos foi reprodutível, podendo ser utilizada com confiança.

Objective: To evaluate the intraexaminer reproducibility of static anthropometric measurements of undergraduate dental students as well as the characteristics and regulating measurements of the dental stools used by them. Methods: Forty volunteers and 6 types of dental stools were evaluated. For the anthropometric measurements the employed equipments were: an adapted office chair, a flexible measuring tape with two adapted rods, a metallic device with a 90 degree central angle, string, a 35 x 24 cm rectangular wooden board, isolating tape and crepe tape. In order to standardize the position of the adapted office chair and the volunteers' feet, the floor was marked with the isolating and crepe tapes. A string was attached to the waist of each volunteer to mark the area corresponding to the kidney region making it possible to measure the seat-renal region area. The examined anthropometric measurements were height, trunk-cephalic heigh, sacral-popliteal distance (OK?), hip width, popliteal height and the seat-renal region height. The evaluated characteristics of the dental stools relative to the seat were depth, horizontal width and minimum/maximum height. The back of the dental stool was evaluated as for the minimum/maximum height adjustment. The anthropometric and dental stool measurements were obtained by a single examiner at two moments with a 1-week interval between the evaluations. Intra-class correlation coefficient (p) was used to estimate the intraexaminer reproducibility. Results: Excellent reproducibility was observed for all anthropometric measurements obtained (p=0.99) as well as for all dental stools evaluated (p=0.99). Conclusion: The method used to obtain the anthropometric and dental stools measurements was reproducible and can be used reliably.