Effect of different bleaching protocols on dental enamel and composite resin

To evaluate changes in microhardness, roughness and surface morphology of dental enamel and composite resin after different tooth bleaching techniques. Material and Methods: Dental fragments from bovine incisors with composite resin restorations were submitted to different bleaching protocols: G1 – daily 8 hours application of a 10% carbamide peroxide (CP) gel during 21 days; G2: 3 applications of 15 minutes of a 38% hydrogen peroxide (H2O2) gel; G3: 38% H2O2 gel associated to irradiation with LED (470nm) during 6 minutes. The Knoop micro hardness of enamel and composite resin were evaluated at 1, 7, 14 and 21 days for G1, and after 1, 2 and 3 sessions for G2 and G3. The roughness and superficial morphology (atomic force microscopy) were evaluated before and at the end of the bleaching treatment. The data were analyzed by Mann-Whitney and Wilcoxon tests (=5%). Results: Significant reduction on enamel hardness was observed after 2 and 3 sessions for G2 and G3. For composite, the reduction occurred after 21 days for G1, and after 3 sessions for G2 and G3 (p<0.05). Significant reduction on roughness and superficial morphology were observed only for enamel of G1 group (p<0.05). Conclusion: The 10% CP gel promoted only superficial alterations on dental enamel, while the 38% H2O2 gel promoted mineral reduction of this dental tissue. All the bleaching protocols promoted reduction on hardness of composite resin.

Relação entre materiais dentários e o complexo dentino-pulpar

Despite the strong valorization of the esthetics and its relationship with restorative materials, the biological principles of any clinical procedure are extremely important to maintain the vitality of the dentin-pulp complex. Dentin and pulp tissue are susceptible to different kinds of irritants such as toxins from microorganisms, traumatic procedures of cavity preparation, as well as toxic components released by restorative materials applied in non recommended clinical situations. Initially, the pulp responds to irritation by starting an inflammatory reaction which involves outward movement of dentinal fluid and intratubular deposition of immunoglobulins, upregulation of odontoblast activities, presence of immune cells and their cytokines as well as local expression of neuropeptides and chemokines. After these initial events, the inflammation process can be resolved associated or not to sclerotic dentin formation and reactionary dentin deposition. If high intensity offensive stimuli are applied to the dentin-pulp complex, death of odontoblasts takes place and consequently pulp ageing or even partial necrosis of this tissue may occurs. Thereby, clinicians need to be aware about the physiological and pathological features of the dentin-pulp complex as well as the possible biological consequences of different clinical procedures. In this way, the dentists should be able to carry out minimally aggressive operative techniques and to select the more appropriate restorative materials for each specific clinical situation in order to obtain excellent clinical results associated to the maintenance of pulp vitality.

Tratamento de recessões gengivais múltiplas: uma abordagem mais conservadora

Periodontal therapy has undergone significant changes in recent decades. While in the past the only goal was to restore gingival health, with no concern about the possible consequences of the disease treatment, currently the procedures are performed in a less invasive manner, to maintain aesthetic periodontal results or even recover them. Gingival recession is an alteration frequently found in patients and may be a complaint for causing various complications. For their treatment, several surgical techniques are reported in the literature. The techniques that are more predictable are those that associate a subepithelial connective tissue graft and a coronally repositioned flap. The original technique consists in performing two vertical incisions for an extensive release of the flap and its stabilization in a coronal position. Although this procedure is extremely widespread in the literature, the search for less invasive surgeries without the use of vertical incisions are the current aim of periodontal plastic surgeries, since they present several advantages. The aim of this paper is to demonstrate a case where adjacent, deep and multiple recessions were present resulting in aesthetic problems, which was resolved by a less invasive approach using a surgical technique in envelope and a subepithelial connective tissue graft.

Importância do tratamento estético periodontal na reabilitação protética

Gingival recession is a common deformity that affects a large number of people. This condition is frequently associated with esthetic complains and may lead to dental hypersensitivity. Thus, various surgical procedures have been proposed to provide root coverage. Since the 1950s, free and pedicle gingival grafts have been greatly used for treating gingival recession. However, after the 1985 Miller gingival recession classification, and with the development of other appropriated techniques that use subepithelial connective tissue grafts, gingival recession treatments have resulted in more predictable outcomes, especially with respect to Class I and II sites, i.e., in the absence of interproximal bone loss. This article reported the importance of aesthetical periodontal treatment in the prosthetic rehabilitation of a patient with a class I gingival recession with 3 mm of vertical extension in the superior canine. The treatment plan consisted of root coverage using subepithelial connective tissue graft (SCTG) associated with construction of new prosthesis.

Associação de prótese fixa, implantes e estética periodontal para reabilitação de pacientes parcialmente edêntulos

Periodontitis is a chronic inflammatory disease that results in the destruction of teeth and their supporting tissues with subsequent tooth loss. The replacement of missing teeth for implant-supported restorations has proven to be a highly predictable treatment method with good long-term prognosis. However, some consequences of tooth loss prevents dental implant placement in an ideal position, where regenerative procedures are necessary for this type of rehabilitation. Less invasive procedures such as conventional prosthesis emerge as a therapeutic option in cases where there is enough bone structure for implants and patient´s non-acceptance for invasive procedures. Thus, this paper aims to present the resolution of rehabilitation through a noninvasive and multidisciplinary treatment. One female patient referred to the clinic presented maladaptive bilateral mandibular fixed prostheses, endodontic lesions, gingival recession, and root sensitivity. For proper resolution of this case, an association among osseointegrated implants, fixed partial prosthesis, tooth extraction, and aesthetic periodontal procedures with the use of subepithelial connective tissue graft was proposed. After two years, the patient shows excellent aesthetics and chewing. Within the limits of this scenario, this paper discusses the various factors that may affect the choice of a particular treatment modality for the rehabilitation of edentulous single spaces.

Importância do tratamento estético periodontal na reabilitação protética

Gingival recession is a common deformity that affects a large number of people. This condition is frequently associated with esthetic complains and may lead to dental hypersensitivity. Thus, various surgical procedures have been proposed to provide root coverage. Since the 1950s, free and pedicle gingival grafts have been greatly used for treating gingival recession. However, after the 1985 Miller gingival recession classification, and with the development of other appropriated techniques that use subepithelial connective tissue grafts, gingival recession treatments have resulted in more predictable outcomes, especially with respect to Class I and II sites, i.e., in the absence of interproximal bone loss. This article reported the importance of aesthetical periodontal treatment in the prosthetic rehabilitation of a patient with a class I gingival recession with 3 mm of vertical extension in the superior canine. The treatment plan consisted of root coverage using subepithelial connective tissue graft (SCTG) associated with construction of new prosthesis.

Proliferação celular em gestações naturais e de conceptos bovinos transgênicos e clonados, que expressam a proteína fluorescente verde (GFP)

Pós-graduação em Ciência e Tecnologia Animal - FEIS

Inquérito sobre a mobilidade articular entre universitários de 18 a 25 anos

Pós-graduação em Saúde Coletiva - FMB

Biological compatibility of some types of endodontic calcium hydroxide and glass ionomer cements

The purpose of this work was to evaluate the biological compatibility of the Sealapex, Apexit, Sealer 26 and Ketac Endo endodontic cements. Polyethylene tubes containing these cements were implanted in the subcutaneous tissue of 40 (forty) rats. The animals were sacrificed after 14 and 90 days. A descriptive analysis of the reactions found in the connective tissue by contact with the cements was performed. The magnitude of inflammatory infiltrate, the presence and predominance of cell types and their distribution as to the filling material and reparative phenomena, such as fibroblastic and angioblastic proliferation and formation of fibrous capsules, were subjectively measured. After 90 days, all cements presented statistically significant reduction of the inflammatory reaction, presence of a fibrous tissue capsule in contact with the opening of the tubes containing the filling materials, and reduction of fibroblastic proliferation. Angioblastic proliferation decreased only for the Sealer 26 and Ketac Endo groups. All cements tested were either partially or totally phagocyted, and the mildest inflammatory response was found for the Sealer 26 group at both evaluation periods.

Morphological aspects of tympanic bulla after ventral osteotomy in cats

To evaluate tympanic bulla healing after experimental ventral osteotomy in cats. Twenty adult cats were submitted to unilateral ventral bulla osteotomy and divided into two groups: cats of A1 group (n=10) were euthanized at 8 weeks and cats of A2 group (n=10), at 16 weeks postoperative. Signs of Horner's syndrome or damage to the inner ear were not found. Open-mouth radiographs taken in the immediate postoperative showed interruption in the contour of the larger compartment of the operated bulla. The result of Mcnemar'test was significant in A2 group (*p=0.0156). Macroscopic exams revealed that the operated bullae were similar to the normal ones, with preservation of the tympanic cavity. Connective tissue at the osteotomy site of the larger compartment was significantly found in the operated bullae in both groups (McNemar test: A1 p=0.0020*; A2 p=0.0078*). Histomorphometric analyses showed that the connective tissue length at the osteotomy site was shorter in A2 group than in the A1 group (Mann-Whitney test: p=0.0021*). Experimental ventral osteotomy did not alter significantly the tympanic bulla conformation and complete regeneration of tympanic bulla frequently did not occur before 16 weeks of postoperative period.

Cholangiocarcinoma in an American Rhea (Rhea Americana araneipes)

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

Avaliação de uma nova abordagem cirúrgico-restauradora para tratamento de recessões gengivais associadas à lesão cervical não-cariosa: estudo clínico controlado randomizado

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Morphological, immunohistochemical and molecular study of renal lesions in canine visceral leishmaniasis (CVL)

Canine visceral leishmaniasis (CVL) is an anthropozoonosis characterized by a clinically chronic progressive disease. Non lymphoid organs are also affected, especially the kidneys. Dogs with leishmaniasis usually die with renal failure despite treatment. Haematoxylin-eosin (HE) staining in kidney tissue sections has low sensitivity for parasite identification. Immunohistochemistry (IHC) and polymerase chain reaction (PCR) are efficient methods for Leishmania sp. antigen and DNA detection in cases of low parasite burden. The present study aims to identify renal lesions of CVL and correlate them with microscopic findings determined by histochemistry, IHC and PCR. Both IHC and PCR provided similar positivity for amastigote identification, 3/20 animals (15%), thus increasing detection of the parasite in renal tissues when compared with histopathologic examination. The lesion most commonly observed with visceral leishmaniasis-positive canine kidney tissue was membranoproliferative glomerulonephritis, followed by interstitial nephritis without correlation to the number of amastigotes.

Nefroblastoma em cão de 4 meses: relato de caso

Renal nephroblastoma is a malignant tumor composed by embryonic tissue that affects mainly puppies. This works reports the occurrence of unilateral renal nephroblastoma in a puppy with four months. The diagnosis was obtained by histopathological examination of mass obtained by exploratory laparotomy, with realization of nephrectomy. The animal died at 15 days post-operatively by the presence of pulmonary metastases. The survival rate with surgical excision of the mass, with or without complementary therapies, can vary with the stage of disease.

Erva mate minimiza as alterações do perfil lipídico promovidas por elevado consumo de sacarose

The yerba mate (Ilex paraguariensis) is composed of bioactive that interfere with lipid metabolism. The objective was to evaluate if daily consumption of mate tea (MT) change the lipid deposits and dyslipidemia caused by excessive consumption of sucrose. Thirty male Wistar rats (40 days old) were divided into four groups: Group C - free access to commercial chow and deionized water; S - free access to commercial food, water and sucrose solution 30% (w/v) in water; MTS and deionized - free access to commercial feed solution, water, 30% sucrose (w/v) and treated with daily infusion of MT (soluble mate Leão Júnior®) via orogastric tube at a dose of 100 mg/kg/mc for 8 weeks. After the trial period the lipid profile was evaluated by the following parameters: a) direct weighing of the retroperitoneal (RP) and epididymal (EPI) adipose tissues; b) determination of plasma total cholesterol, triglycerides and HDL cholesterol concentration. The MT promoted the reduction of 1.4 times in both tissues RP and EPI in MTS group compared to group S. Treatment with MT decreased 2.7 times triglyceride in the MTS group compared with the group S. The sucrose consumption did not alter the plasma cholesterol concentration, however the consumption of MT significantly reduced total cholesterol circulating. The HDL cholesterol concentration, in the MTS group, showed higher concentration than in group S (1.3 times). MT prevents in young male rats the increase of lipid deposits and dyslipidemia caused by excessive consumption of sucrose.