Microabrasion in tooth enamel discoloration defects: three cases with long-term follow-ups

Superficial irregularities and certain intrinsic stains on the dental enamel surfaces can be resolved by enamel microabrasion, however, treatment for such defects need to be confined to the outermost regions of the enamel surface. Dental bleaching and resin-based composite repair are also often useful for certain situations for tooth color corrections. This article presented and discussed the indications and limitations of enamel microabrasion treatment. Three case reports treated by enamel microabrasion were also presented after 11, 20 and 23 years of follow-ups.

The fitness of copings constructed over UCLA abutments and the implant, constructed by different techniques: casting and casting with laser welding

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Use of a new fibrin sealant and laser irradiation in the repair of skull defects in rats

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Is bone transplantation the gold standard for repair of alveolar bone defects?

New strategies to fulfill craniofacial bone defects have gained attention in recent years due to the morbidity of autologous bone graft harvesting. We aimed to evaluate the in vivo efficacy of bone tissue engineering strategy using mesenchymal stem cells associated with two matrices (bovine bone mineral and α-tricalcium phosphate), compared to an autologous bone transfer. A total of 28 adult, male, non-immunosuppressed Wistar rats underwent a critical-sized osseous defect of 5 mm diameter in the alveolar region. Animals were divided into five groups. Group 1 (n = 7) defects were repaired with autogenous bone grafts; Group 2 (n = 5) defects were repaired with bovine bone mineral free of cells; Group 3 (n = 5) defects were repaired with bovine bone mineral loaded with mesenchymal stem cells; Group 4 (n = 5) defects were repaired with α-tricalcium phosphate free of cells; and Group 5 (n = 6) defects were repaired with α-tricalcium phosphate loaded with mesenchymal stem cells. Groups 2-5 were compared to Group 1, the reference group. Healing response was evaluated by histomorphometry and computerized tomography. Histomorphometrically, Group 1 showed 60.27% ± 16.13% of bone in the defect. Groups 2 and 3 showed 23.02% ± 8.6% (p = 0.01) and 38.35% ± 19.59% (p = 0.06) of bone in the defect, respectively. Groups 4 and 5 showed 51.48% ± 11.7% (p = 0.30) and 61.80% ± 2.14% (p = 0.88) of bone in the defect, respectively. Animals whose bone defects were repaired with α-tricalcium phosphate and mesenchymal stem cells presented the highest bone volume filling the defects; both were not statistically different from autogenous bone.

Obturator prostheses versus free tissue transfers: a systematic review of the optimal approach to improving the quality of life for patients with maxillary defects

Patient perspectives on the treatment options for maxillary defects, which include free tissue transfers or obturator prostheses, may help eliminate current uncertainty as to the best choice of treatment plan. The purpose of this systematic review was to evaluate the quality of life (QoL) of patients with maxillary defects who had undergone restoration with obturator prostheses and/or free tissue transfers. A systematic search of Medline/PubMed and Web of Science databases for articles published before April 2015 was performed by 2 independent reviewers. A manual search of articles published from January 2005 to March 2015 was also conducted. Studies published in English that evaluated the QoL in patients with head and neck cancers were included. The Cohen kappa method was used to calculate inter-reviewer agreement. Ten studies were included. The University of Washington Head and Neck Questionnaire (UW-QOL) was most commonly used to measure QoL. The majority of maxillary defects were Class IIa-b. Two studies reported that the global QoL for patients with obturator prostheses is equivalent to or even better than that of other chronic disease populations. One study revealed no significant difference in QoL when the 2 treatment options were compared. The limited data indicate that the QoL of patients treated with obturator prostheses and that of patients free of tumors is similar. Well-designed clinical studies are necessary to draw definitive conclusions about how obturator prostheses compare with free tissue transfers in terms of affecting patient QoL.

Evaluation of crystallized biosilicate in the reconstruction of calvarial defects

The objective of this study was to assess the bone repair process of crystallized Biosilicate in surgically created defects on rats' calvaria. This biomaterial was recently developed for odontological use. We used fifteen rats (rattus norvegicus albinus, Wistar), and two 5 mm surgical defects were performed on each of them; the defects were made with trephine drill on the calvarium region prior to the biomaterial placement. Groups were divided as follows: Group 1-defect filled with clot; Group 2-defect filled with crystallized Biosilicate. After 7, 14 and 28 days the animals were killed, the parts were retrieved and slides were prepared for histological studies. Bone formation was satisfactory in all groups, with direct contact between biomaterial surface and bone and absence of infection signs. The 28 days periods showed better results, and statistically significant difference between Clot Group (90.2 %) and Biosilicate (58 %; p = 0.002) was seen, regarding presence of bone tissue on the surgical defects. Our study revealed that defects filled with clot present better results on bone formation compared to crystallized Biosilicate, which is considered a biocompatible material with favorable osteoconductive properties.

Seal, replacement or monitoring amalgam restorations with occlusal marginal defects? Results of a 10-year clinical trial

The aim of this prospective and blind clinical trial was to assess the effectiveness of sealing localized marginal defects of amalgam restoration that were initially scheduled to be replaced. A cohort of twenty six patients with 60 amalgam restorations (n=44Class I and n=16Class II), that presented marginal defects deviating from ideal (Bravo) according to USPHS criteria, were assigned to either sealing or replacement groups: A: sealing n=20, Replacement n=20, and no treatment (n=20). Two blind examiners evaluated the restorations at baseline (K=0.74) and after ten years (K=0.84) according with USPHS criteria, in four parameters: marginal adaptation (MA), secondary caries (SC), marginal staining (MS) and teeth sensitivity (TS). Multiple comparison of restorations degradation/upgrade was analyzed by Friedman test and the comparisons within groups were performed by Wilcoxon test. After 10 years, 44 restorations were assessed (73.3%), Group A: n=14 and Group B: n=16; and Group C: n=14 sealing and replacement amalgam restorations presented similar level of quality in MA (p=0.76), SC (p=0.25) and TS (p=0.52), while in MS (p=0.007) presented better performance in replacement group after 10-years. Most of the occlusal amalgam restorations with marginal gaps showed similar long term outcomes than the restorations were sealed, replaced, or not treated over a 10-year period. Most of the restorations of the three groups were clinically acceptable, under the studied parameters. All restorations had the tendency to present downgrade/deterioration over time.

Mesenchymal stem cell enhances chondral defects healing in horses

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Bone substitutes for peri-implant defects of postextraction implants

Placement of implants in fresh sockets is an alternative to try to reduce physiological resorption of alveolar ridge after tooth extraction. This surgery can be used to preserve the bone architecture and also accelerate the restorative procedure. However, the diastasis observed between bone and implant may influence osseointegration. So, autogenous bone graft and/or biomaterials have been used to fill this gap. Considering the importance of bone repair for treatment with implants placed immediately after tooth extraction, this study aimed to present a literature review about biomaterials surrounding immediate dental implants. The search included 56 articles published from 1969 to 2012. The results were based on data analysis and discussion. It was observed that implant fixation immediately after extraction is a reliable alternative to reduce the treatment length of prosthetic restoration. In general, the biomaterial should be used to increase bone/implant contact and enhance osseointegration.

Análise da resistência à fadiga de tubos de aço API 5CT N80 Tipo Q soldados via processo de indução magnética de alta frequência (HFIW)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)