Novel strategy to detect and locate periodontal pathogens: The PNA-FISH technique.

PURPOSE: We aim to develop peptic nucleic acid (PNA) probes for the identification and localization of Aggregatibacter actinomycetemcomintans and Porphyromonas gingivalis in sub-gingival plaque and gingival biopsies by Fluorescence in situ Hybridization (FISH). METHODS: A PNA probe was designed for each microorganism. The PNA-FISH method was optimized to allow simultaneous hybridization of both microorganisms with their probe (PNA-FISH multiplex). After being tested on representative strains of P. gingivalis and A. actinomycetemcomitans, the PNA-FISH method was then adapted to detect microorganisms in the subgingival plaque and gingival samples, collected from patients with severe periodontitis. RESULTS: The best hybridization conditions were found to be 59°C for 150min for both probes (PgPNA1007 and AaPNA235). The in silico sensitivity and specificity was both 100% for PgPNA1007 probe and 100% and 99.9% for AaPNA235 probe, respectively. Results on clinical samples showed that the PNA-FISH method was able to detect and discriminate target bacteria in the mixed microbial population of the subgingival plaque and within periodontal tissues. CONCLUSION: This investigation presents a new highly accurate method for P. gingivalis and A. actinomycetemcomitans detection and co-location in clinical samples, in just few hours. With this technique we were able to observe spatial distribution of these species within polymicrobial communities in the periodontal pockets and, for the first time with the FISH method, in the organized gingival tissue.

Relationship between invasion of the periodontium by periodontal pathogens and periodontal disease: a systematic review.

Bacterial invasion of the periodontal tissues has been suggested as a relevant step in the etiopathogenesis of periodontal disease. However, its exact importance remains to be defined. The present systematic review assessed the scientific evidence concerning the relationship between the quality or quantity of periodontal microbiota in periodontal tissues and development of periodontal disease. The databases Medline-PubMed, Cochrane-CENTRAL, ISI Web of Knowledge and SCOPUS were searched, up to January 2014. Studies that reported evaluation of periodontal pathogens invasion on human tissues were selected. The screening of 440 title/abstracts elected 26 papers for full-text reading. Twenty three papers were subsequently excluded because of insufficient data or a study protocol not related to the objectives of this systematic review. All included studies were case-control studies that evaluated intracellular or adherent bacteria to epithelial cells from periodontal pockets versus healthy sulci. Study protocols presented heterogeneity regarding case and control definitions and methodological approaches for microbial identification. No consistent significant differences were found related to the presence/absence or proportion of specific periopathogens across the studies, as only one study found statistically significant differences regarding the presence of A. actinomycetemcomitans (p = 0.043), T. forsythia (P < 0.001), P. intermedia (P < 0.001), C. ochracea (P < 0.001) and C. rectus (P = 0.003) in epithelial cells from periodontal pockets vs. healthy sulci. All studies reported a larger unspecific bacterial load in or on the epithelial cells taken from a diseased site compared to a healthy sulcus. The current available data is of low to moderate quality and inconsistent mainly due to study design, poor reporting and methodological diversity. As so, there is insufficient evidence to support or exclude the invasion by periodontal pathogens as a key step in the etiopathogenesis of periodontal disease. Further research is needed.

Coroas totalmente cerâmicas em caninos decíduos: abordagem multidisciplinar / All-ceramic crowns on deciduous canines: multidisciplinary approach

Introdução: Qualquer dente pode se tornar permanentemente impactado. Nos casos de dentes anteriores impactados, a harmonia e a estética de um sorriso pode ser diminuída. Existem três opções principais: a observação (sem tratamento), o deslocamento (tratamento ortodôntico ou cirúrgico) e a extração. Objetivo: O objetivo deste trabalho é discutir as várias possibilidades de tratamento para os casos de caninos maxilares impactados bilateral, bem como para explicar os aspectos clínicos que devem ser levados em consideração. Descrição do caso: Este trabalho descreve uma situação clínica de impactação dos dois caninos maxilares, resolvida através da extração de ambos os caninos permanentes, seguida da colocação de coroas cerâmicas nos caninos decíduos, após gengivectomia. Conclusão: Apesar de terem surgido algumas dificuldades durante o tratamento, tais como a baixa posição da margem gengival, a abordagem multidisciplinar do tratamento descrito foi adequada para alcançar um sorriso agradável e uma oclusão funcional.

Introduction: Any permanent tooth may become impacted. In cases of anterior teeth impaction, the harmony and aesthetics of a smile are sometimes diminished. There are three main treatment options: observation (no treatment), relocation (orthodontic therapy or surgical) and extraction. Objective: The objective of this case report is to discuss the various treatment possibilities towards bilateral maxillary canine impaction as well as to explain the clinical considerations that must be taken into account. Case description: This paper presents a clinical situation of bilateral maxillary canine impaction solved by the extraction of both teeth and followed by the placement of ceramic crowns on the deciduous canines, as well as a corrective gingivectomy. Conclusion: Despite some difficulties emerged during the treatment such as the low position of the gingival margin, the authors believe that the multidisciplinary approach of the treatment described is one good option to achieve a pleasant smile and functional occlusion.

CAD-CAM all-ceramic fully sintered zirconia crowns for the oral rehabilitation of an amelogenesis imperfecta case / Coroas CAD-CAM de zircônia totalmente sinterizada para reabilitação oral de um caso de amelogenesis imperfecta

Purpose: To present a case report of a patient with amelogenesis imperfecta rehabilitated with 26 CAD-CAM all-ceramic fully sintered zirconia crowns.Case description: A male subject, 28 year-old, sought dental treatment presenting a clinical condition compatible with amelogenesis imperfecta. All teeth had yellow, brown, and white areas of weak enamel. Composite restorations were present on teeth 14, 16, 24, 25, 26, 27, and 46; dental caries were shown on teeth 36, 37, and 47. Hipersensitivity was reported. The treatment included fully sintered zirconia crowns for all teeth, using a CAD-CAM system. No problems of marginal adaptation of the crowns were detected, and the final results were satisfactory for both the patient and the clinician. Conclusion: The clinical rehabilitation of an amelogenesis imperfecta case is a challenge, and a multidisciplinary approach is required. Zirconia all-ceramics crowns are an excellent option to restore dental aesthetics as the opaque zirconia coping can mask dischromic abutments, and the crowns have biocompatibility and improved physical properties.

Objetivo: Apresentar o caso clínico de um paciente com amelogenesis imperfecta, que foi reabilitado com 26 coroas CAD-CAM de zircônia totalmente sinterizada. Descrição do caso: Um sujeito do sexo masculino, 28 anos, procurou tratamento odontológico apresentando uma condição clínica compatível com amelogenesis imperfecta. Todos os dentes tinham áreas amarelas, marrons e brancas de esmalte enfraquecido. Havia restaurações de resina composta nos dentes 14, 16, 24, 25, 26, 27 e 46; cárie dentária estava presente nos dentes 36, 37 e 47. Relatou-se hipersensibilidade dentária. O tratamento incluiu coroas de zircônia totalmente sinterizada para todos os dentes, usando um sistema CAD-CAM. Nenhum problema de adaptação marginal das coroas foi detectado e os resultados finais foram satisfatórios para ambos o paciente e o clínico. Conclusão: A reabilitação clínica de amelogenesis imperfecta é um desafio e a abordagem multidisciplinar deve ser mandatória. As coroas de zircônia são uma excelente opção para a reabilitação de pacientes com esta anomalia, pois o opaco dos copings de zircônia pode mascarar as diferentes cores dos pilares e o resultado final é esteticamente aceitável, com biocompatibilidade e propriedades físicas superiores.