SEM analyses of bacterial contamination of e-PTFE membranes and GTR clinical results.

The aim of the present study was to determine whether bacterial contamination of expanded polytetrafluoroethylene (e-PTFE) membranes and the degree of membrane exposure could affect the clinical results of guided tissue regeneration (GTR). Seven patients (aged 42 to 58 years) presented with twenty intrabony defects that were treated by GTR + DFDBA (decalcified freeze-dried bone allograft). Gingival recession, probing depths, and clinical attachment levels were recorded before surgery and 10 months subsequently. Exposure of the membrane was recorded at the moment of removal. The membranes were analyzed in three distinct regions by scanning electron microscopy (SEM): collar, medial and apical regions. The presence of host cells adhering to the e-PTFE membrane was determined and bacterial contamination was quantified as per Simion et al. (1994). Statistical analysis did not show significant differences for bacterial contamination or for the presence of host cells on the membrane surface at different levels of exposure (up to 30%, from 31% to 60%, and from 61% to 75%). Results were considered statistically significant at p < 0.05, according to the Kruskal-Wallis rank sum test. Exposure of the membrane and bacterial contamination did not modify the levels recorded. Bacterial contamination had an adverse effect on bone defect filling.

Implicaçöes da anatomia radicular dos molares na terapêutica periodontal / Molar root anatony implications in periodontal treatment

As doenças periodontais têm, como fator etiológico primário, a placa bacteriana e seus subprodutos. Uma multiplicidade de fatores influenciam na qualidade desta placa, bem como em seu potencial patogênico. As bases da terapêutica periodontal residem, principalmente, na manutençäo de uma microbiota compatível com saúde, através do controle de placa e da descontaminaçäo da superfície radicular. Neste aspecto, o fator anatomia radicular pode exercer influência tanto em termos de prognóstico, quanto de tratamento. Este artigo se propöe analisar, com base na literatura, fatores anatônicos das raízes de molares que devem ser considerados ao se avaliar o status periodontal de um paciente

Diabetes: um fator de risco para doença periodontal. Quando? / Diabetes: a risk factor for periodontal disease. When?

A década de 90 têm sido marcada por uma permanente preocupaçäo de pesquisadores em definir mais claramente quais fatores ou doenças sistêmicas se constituem condiçöes de risco para a doença periodontal. A busca de grupos de risco vêm estimulando novos estudos e recentes análises sobre possíveis relaçöes entre doença periodontal e fatores sistêmicos. Dentre esses fatores incluem-se as disfunçöes sistêmicas na resposta do hospedeiro, doenças sistêmicas, alteraçöes hormonais, alteraçöes muco-cutâneas, drogas, fumo, doenças de outros órgäos com manifestaçöes no periodonto e, inclusive, as carências nutricionais. Dentro deste contexto, este trabalho objetiva compilar o corrente entendimento sobre o papel do diabetes na doença periodontal

Passaporte para o futuro / Passport for the future

Muitos cirurgiöes-dentistas têm embarcado numa idéia: buscar especializaçäo, atualizaçäo ou aprimoramento no exterior. O país preferido säo os Estados Unidos. Cursos de uma semana em Nova York com os maiores especialistas da área saem até por 1250 dólares

PSR: um método simplificado de diagnóstico periodontal / PSR: periodontal screening & recording

Neste artigo, os autores apresentam o Periodontal Screening & Recording (PSR), um sistema simplificado de exame periodontal para uso rotineiro por todas as áreas da odontologia, o qual tem por objetivo identificar, no ambiente da clínica geral, pacientes que necessitam tratamento periodontal especializado, pacientes com doenças em estágios iniciais e indivíduos com saúde periodontal

Especialista ou clínico geral? / Specialist or general dentist?

Profissionais falam sobre o seu trabalho e discutem as vantagens e desvantagens de ser Clínico Geral ou Especialistas

Ultra-estrutura do epitélio sulcular na gengiva humana clinicamente normal e na doença periodontal / Junctional epithelium ultrastructure in clinically normal human gingiva and in periodontal disease

O objetivo desta pesquisa é estudar, no mesmo paciente, a ultra-estrutura do epitélio sulcular tanto na normalidade clínica quanto frente à doença periodontal. Cinco pacientes que apresentavam áreas de normalidade clínica e de doença periodontal foram estudados. Três biópsias gengivais de cada área foram obtidas, utilizando-se a incisão de bisel invertido. Os tecidos assim obtidos foram submetidos ao processamento histológico para microscopia óptica e eletrônica. Os resultados observados foram os seguintes, para as amostras representativas de doença periodontal: 1) As cisternas perinucleares apresentaram-se ocasionalmente alargadas. 2) O espaço intercelular estava aumentado e freqüentemente preenchido por um material granular eletrondenso. 3) Desmossomas típicos, embora em menor quantidade, foram observados. 4) A lâmina basal freqüentemente apresentava-se interrompida no epitélio sulcular severamente alterado pela doença periodontal

Effects of citric acid and fibronectin and laminin application in treating periodontitis / Efeito do ácido cítrico, fibronectina e aplicação de laminin no tratamento periodontal

To determine the effect on new connective tissue attachment of citric acid conditioning and fibronectin-laminin application in treating naturally occurring periodontitis, all 4 quadrants in each of 2 Beagle dogs were used. Each quadrant included: P2, P3, P4 and M1 teeth. 2 treatment modalities were employed and comparatively analyzed for differences in histological healing responses at 120 days after surgery. The treatments were: (1) surgery (mucoperiosteal flaps) plus citric acid; (2) surgery plus citric acid followed by fibronectin-laminin application. After scaling and root planing, coronal and root surface reference notches were placed for histometric measurements. Following each of the randomly assigned treatments, flaps were sutured. After sacrifice, tissue blocks of treated areas were decalcified and serially cut, obtaining bucco-lingual and mesio-distal sections. Using a Filar micrometer, 5 distances were measured on the buccal aspect: (1) from root surface notch to alveolar bone crest; (2) from root surface notch to coronal extent of the cementum; (3) from root surface notch to apical extent of the junctional epithelium; (4) from free gingival margin to apical extent of junctional epithelium; (5) from the coronal notch to the alveolar bone crest. Results showed no differences among the 5 measurements between the 2 treatments tested. On mesio-distal sections, surface area determinations were made in the furcations, evaluating the space occupied by new connective tissue, with or without bone, or by epithelium. For this, images were digitized using a Zeiss IBAS Image analysis system with a 4mB of array processor memory coupled to a Newvicon TV camera and a microcomputer. Significant differences were found, with increased values for both regenerative connective tissue and bone when surgery plus citric acid was followed by fibronectin-laminin application. Often, these tissues filled completely furcation areas above root surface reference notches

Revascularization following a combined gingival flap-split thickness flap procedure in monkeys / Revascularização após cirurgia a retalho em macacos

A combined technique (gingival flap-split thickness flap) was performed in monkeys. The clinical, histological and microvascular aspects of healing were studied, mainly focusing on the gingival flap, since some of the vessels supplying this area were severed during the second phase of the procedure. The animals were perfused with a combined solution of Pelikan carbon black and 10 por cento formalin solution and killed from 1 to 35 days postoperatively. Cleared specimens and regular histology were obtained. It was concluded that: (1) the remaining periosteal vessels and surrounding structures provided enough nutrition for the survival of the gingival flap, (2) the microvascularization was normal at the 14 days postoperative period in both the gingival flap and the apically positioned split areas and (3) the exposed connective tissue remained narrow and exhibited an irregular vascular arrangement throughout the experiment