Tartrate-resistant acid phosphatase activity and glutathione levels are modulated during hFOB 1.19 osteoblastic differentiation.

Tartrate-resistant acid phosphatase (TRAP) is a well-known marker of osteoclasts and bone resorption. Here we have investigated whether osteoblast-like cells (hFOB 1.19) present TRAP activity and how would be its pattern of expression during osteoblastic differentiation.

Basic research methods and current trends of dental implant surfaces.

Among dental implant design alterations, surface modifications have been by far the most investigated topic. Regarding implant surface research, the lack of hierarchical approaches relating in vitro, in vivo, clinical trials, and ex vivo analyses has hindered biomaterials scientists with clear informed rationale guidelines for implant surface design. This manuscript provides a critical hierarchical overview of the in vitro, laboratory in vivo, clinical, and ex vivo methodologies used to investigate the performance of novel biomaterials aiming to allow dental professionals to better evaluate the past, present, and future dental implant surface research.

Expression analysis of matrix metalloproteinase-9 in epithelialized and nonepithelialized apical periodontitis lesions.

Objective: The objective of this study was to determine the expression of matrix metalloproteinase-9 (MMP-9) in apical periodontitis lesions.

Study Design: Nineteen epithelialized and 18 nonepithelialized apical periodontitis lesions were collected after periapical surgery. After histological processing, serial sectioning, H&E staining, and microscopic analysis, 10 epithelialized and 10 nonepithelialized lesions were selected for immunohistochemical analysis for MMP-9 and CD 68.

Morphometric evaluation of the repair of critical-size defects using demineralized bovine bone and autogenous bone grafts in rat calvaria.

Objective: To evaluate the repair of critical-size bone defects in rats treated with demineralized bovine bone (DBB) compared with autogenous bone (AB).

Material And Method: A bone defect of 8 mm in diameter was created in the calvaria of 50 Rattus norvegicus, treated either with DBB or AB. Sub-groups of five rats of each group were killed at 7, 14, 21, 30 and 90 days post-operatively, and the skulls were removed and processed histologically.

Healing of critical-size cranial defects in guinea pigs using a bovine bone-derived resorbable membrane.

Purpose: To investigate the healing of critical-size cranial bone defects (9-mm-diameter) in guinea pigs treated with a bovine bone-derived resorbable membrane.

Materials And Methods: A sample of 42 guinea pigs was divided into test (n = 20), control (n = 20), and standard (n = 2) groups. A full-thickness trephine defect was made in the fronto-parietal bone of each animal.

AXIN2 and CDH1 polymorphisms, tooth agenesis, and oral clefts.

Background: AXIN2 and CDH1 genes play important roles during craniofacial morphogenesis. Mutations in these genes have been described in families presenting colorectal cancer and tooth agenesis, and gastric cancer and cleft lip/palate (CL/P). Oral clefts have been associated with tooth agenesis.

Differential patterns of receptor activator of nuclear factor kappa B ligand/osteoprotegerin expression in human periapical granulomas: possible association with progressive or stable nature of the lesions.

Receptor activator of nuclear factor kappa B ligand (RANKL) and osteoprotegerin (OPG) are expressed in apical periodontitis, suggesting a role for these molecules during lesion development. However, the profiles of RANKL/OPG expression in periapical lesions remain unknown. In this study we investigated the patterns of RANKL and OPG mRNA expression by real-time polymerase chain reaction in human periapical granulomas (N = 44) and compared them with sites presenting characteristic bone resorbing activity: healthy (n = 14) and orthodontically stretched and compressed periodontal ligament (n = 26), healthy gingiva (n = 24), chronic gingivitis (n = 32), and chronic periodontitis (n = 34) samples.

Expression of metalloproteinases and their tissue inhibitors in inflamed gingival biopsies.

Objectives: Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) are known to be involved in the periodontal disease process. Results of in vivo MMPs and TIMPs gene expressions in the gingiva, though, are still controversial. In the present study, we compared the gene expression of MMP-1, -2, -9, -13 and TIMP-1, -2 in healthy and inflamed gingiva.

Optimizing the procedure for mercury recovery from dental amalgam.

Mercury, as any other heavy metal, may cause environmental damages due to its accumulation and biotransformation. Dental offices, whether private or institutional, use dental amalgam as a restorative material on a daily basis. Dental amalgam is composed of mercury (50%), silver (30%) and other metals.

Physicochemical characterization of two deproteinized bovine xenografts.

Calcium phosphate salts, or more specifically hydroxyapatite, are products of great interest in the fields of medical and dental science due to their biocompatibility and osteoconduction property. Deproteinized xenografts are primarily constituted of natural apatites, sintered or not. Variations in the industrial process may affect physicochemical properties and, therefore, the biological outcome.

Effect of roughness of zirconia and titanium on fibroblast adhesion.

The aim of this study was to investigate the adhesion (4 and 24 h) and the morphology of fibroblast Balb/c 3T3 seeded onto polystyrene, partially stabilized (ZrO(2)Y(2)O(3)), stabilized zirconia ceramic (3YTZP), and pure titanium (Ti, grade 2). Initial cell adhesion (4 h) was greater (P < 0.05, analysis of variance and Tukey's Multiple Comparisons Test) onto ZrO(2)Y(2)O(3) and polystyrene than in Ti and 3YTZ.

NUCEL (Cell and Molecular Therapy Center): a multidisciplinary center for translational research in Brazil.

Social and economical development is closely associated with technological innovation and a well-developed biotechnological industry. In the last few years, Brazil's scientific production has been steadily increasing; however, the number of patents is lagging behind, with technological and translational research requiring governmental incentive and reinforcement. The Cell and Molecular Therapy Center (NUCEL) was created to develop activities in the translational research field, addressing concrete problems found in biomedical and veterinary areas and actively searching for solutions by employing a genetic engineering approach to generate cell lines over-expressing recombinant proteins to be transferred to local biotech companies, aiming at furthering the development of a national competence for local production of biopharmaceuticals of widespread use and of life-saving importance.

Evaluation of the cytocompatibility of mixed bovine bone.

Treatment of bovine bone with peroxides and chaotropic agents aims to obtain an acellular bone matrix that is able to maintain the collagen-apatite complex and a higher mechanical resistance, a mixed biomaterial hereby named mixed bovine bone (MBB). The purpose of this study was to evaluate the cytocompatibility of MBB and cell-MBB interaction. Cell morphology, number of viable cells, ability to reduce methyltetrazolium and to incorporate neutral red upon exposure to different concentrations of the hydrosoluble extract of MBB were assessed in Balb-c 3T3 cells according to ISO 10993-5 standard.

Comparative histomorphometric and tomographic analysis of maxillary sinus floor augmentation in rabbits using autografts and xenografts.

Our goal was to evaluate bone neoformation promoted by a bovine xenograft composite (XC) compared with autogenous graft for maxillary sinus augmentation in a rabbit model. The left maxillary sinus of 18 male rabbits was filled with 200 mg of cortical and cancellous autogenous bone and the right sinus was filled with 200 mg of a composite comprised organic and inorganic bovine matrices, pool of bBMPs and collagen. Postoperative implant intervals of 2, 4, and 8 weeks were analyzed.

Tibial segmental bone defect treated with bone plate and cage filled with either xenogeneic composite or autologous cortical bone graft. An experimental study in sheep.

Tibia segmental defect healing in sheep were clinically, radiographically and histologically evaluated. Twelve young sheep aged four to five months were divided into two groups, G1 and G2. A 3.

Expression of matrix metalloproteinases-2 and -9 and RECK during alveolar bone regeneration in rat.

MMPs are endopeptidases that play a pivotal role in ECM turnover. RECK is a single membrane-anchored MMP-regulator. Here, we evaluated the temporal and spatial expression of MMP-2, MMP-9, and RECK during alveolar bone regeneration.

Evaluation of bone height and bone density after tooth extraction: an experimental study in minipigs.

Objective: The objective of this study was to radiographically quantify bone density and bone height preservation in tooth extraction alveolus filled with xenograft.

Study Design: The maxillary and mandibular fourth deciduous molars and fourth premolars of 6 minipigs were removed. Randomly, in 3 animals the right side was used as the test side and in the other 3 animals the left side was the test side.

Defining subphenotypes for oral clefts based on dental development.

Individuals with clefts present considerably more dental anomalies than do individuals without clefts. We used dental development to subphenotype clefts with the goal of identifying cleft subgroups that could have specific genetic contributions. We examined 1000 individuals, 500 with clefts and 500 without.

Culture of osteogenic cells from human alveolar bone: a useful source of alkaline phosphatase.

The aim of this study was to obtain membrane-bound alkaline phosphatase from osteoblastic-like cells of human alveolar bone. Cells were obtained by enzymatic digestion and maintained in primary culture in osteogenic medium until subconfluence. First passage cells were cultured in the same medium and at 7, 14, and 21 days, total protein content, collagen content, and alkaline phosphatase activity were evaluated.

Effect of bovine bone morphogenetic proteins on radius fracture healing in rabbits.

Purpose: To investigate the effect of bovine bone morphogenetic proteins (bBMPs) bound to hydroxyapatite plus collagen in the healing of unstable radius fractures.

Methods: A transverse fracture was induced at the mid of the diaphysis in both radii on 15 Norfolk rabbits with average age of 5.5 months and 3.

MMP gene polymorphisms as contributors for cleft lip/palate: association with MMP3 but not MMP1.

Objective: Orofacial clefts result from failures of developing embryonic facial and palatal processes to either completely merge or fuse. Normal development of the facial primordia requires remodelling of the extracellular matrix, which is mediated in part by the matrix metalloproteinases (MMPs). MMPs can be considered a group of candidate proteins for the etiology of cleft lip with or without cleft palate (CL/P) due to their role in craniofacial modelling.

Intraoral features of Apert's syndrome.

Objective: To evaluate the intraoral features of patients with Apert's syndrome in treatment at the Hospital of Rehabilitation and Craniofacial Anomalies of University of São Paulo (HRAC-USP), a national reference center for treatment of craniofacial anomalies in Brazil.

Study Design: In this retrospective study, of 56,000 patients registered at HRAC-USP, 36 patients were diagnosed with Apert's syndrome and were either examined or had their medical files evaluated, aiming to characterize lip posture, mouth shape, maxillary hypoplasia, palatal morphology, dental anomalies, and malocclusion.

Results: Most patients were characterized as mouth breathers for presenting with hypotonic lips and trapezoidal-shaped mouths.

The role of matrix metalloproteinases in the oral environment.

This review focuses specifically on matrix metalloproteinases (MMPs) and their role in physiological and pathological extracellular matrix (ECM) remodeling and degradation processes in the oral environment. A group of enzymes capable of degrading almost all ECM proteins, MMPs contribute to both normal and pathological tissue remodeling. The expression of different MMPs may be upregulated in pathological conditions such as inflammation and tumor invasion.

Orthodontic movement in bone defects filled with xenogenic graft: an experimental study in minipigs.

Introduction: In this study, we investigated whether it is possible to orthodontically move a tooth into an adjacent bone defect previously filled with xenogenic grafting material, with emphasis on the reactions of the tooth roots and adjacent tissues.

Methods: Six minipigs were used. In each animal, 4 defects were created at the mesial aspects of the maxillary and mandibular first permanent molars; the defects on the right were filled with the xenograft (test side), and the opposite defects (control side) were filled with blood clots and allowed to heal spontaneously.