Endocannabinoid system and periodontitis: mechanisms and therapeutic implications / Sistema endocanabinoide e periodontite: mecanismos e implicações terapêuticas

Introdução: A periodontite é um importante problema de saúde pública. Embora o princípio da terapia da periodontite esteja focado principalmente na remoção do biofilme dental e dos fatores associados, sua fisiopatologia registra diferentes eventos moleculares e inflamatórios relacionados ao sistema imunológico do hospedeiro, como a participação do sistema endocanabinoide. Objetivo: Esta revisão teve como objetivo explorar e elucidar os mecanismos e papéis do sistema endocanabinoide na fisiopatologia da periodontite e suas possibilidades para futuras terapias relacionadas. Material e método: Realizou-se uma busca eletrônica na plataforma PubMed por estudos envolvendo a ação do sistema endocanabinoide sobre a periodontite. Resultado: Dezenove estudos clínicos e pré-clínicos foram incluídos nesta revisão narrativa. Conclusão: Os receptores canabinoides tipo 1 e 2 são componentes integrais do sistema endocanabinoide e manifestam-se de várias formas nos tecidos periodontais. As ações e mecanismos através dos quais os receptores canabinoides são ativados em locais saudáveis ou inflamados continuam a ser o foco de investigações em curso. Além disso, os fitocanabinoides e canabinoides sintéticos apresentam potencial como tratamentos, com estudos pré-clínicos indicando benefícios na redução da inflamação e na facilitação da reparação dos tecidos.

Introduction: Periodontitis is a major public health problem. Although the principle of periodontitis therapy is mainly focused on removing dental biofilm and associated factors, its physiopathology enrolls different molecular and inflammatory events related to the host immune system, as the participation of the endocannabinoid system. Objective: This review aimed to explore and elucidate the mechanisms and roles of the endocannabinoid system on periodontitis physiopathology and its possibilities for future related therapies. Material and method: An electronic search was carried out on the PubMed platform for studies involving the action of the endocannabinoid system on periodontitis. Result: Nineteen clinical and preclinical studies were included in this narrative review. Conclusion: Cannabinoid receptors type 1 and 2 are integral components of the endocannabinoid system, manifesting in various forms in the periodontal tissues. The actions and mechanisms through which cannabinoid receptors are activated in healthy or inflamed sites remain the focus of ongoing investigations. Moreover, phytocannabinoids and synthetic cannabinoids show therapeutic potential, with pre-clinical studies indicating benefits in reducing inflammation and facilitating tissue repair

Effect of electric, ultrasonic and manual toothbrushes on biofilm removal and gingivitis control: in vitro and parallel randomized controlled clinical trial study

Aim: To evaluate the effect of manual (M), electric (E) and ultrasonic (US) toothbrushes on the removal of oral biofilm and control of gingivitis. Also, the roughness and tooth wear production were evaluated in vitro. Methods: For the in vitro analyses, thirty bovine dentin specimens were submitted to a 3-month brushing simulation (9 minutes) with the three types of toothbrushes (n = 10). Subsequently, a randomized controlled clinical trial was performed with 36 patients divided into 3 groups according to the toothbrushes used (n = 12). Gingival index, visible plaque index and the volume of crevicular fluid were evaluated at baseline and 3 months after the beginning of the toothbrush use. Furthermore, the performance of the biofilm removal per brushing cycle of 1 and 3 minutes with each toothbrush was made monthly until the end of the experiment. Results: The US group had the highest dentin wear. Clinically, the US group had a lower plaque index at 3 months than the M group. The M group also showed less biofilm removal efficiency from the second month of follow-up and more worn bristles at the end of the 3 month period than the E and US groups. Conclusion: The ultrasonic, electric and manual toothbrushes showed no differences in gingivitis control in the present study. The ultrasonic and electric toothbrushes had a more significant effect on biofilm removal than a manual toothbrush, but the ultrasonic toothbrush promoted greater dentin tissue wear

Periodontal regeneration: is it still a goal in clinical periodontology?

Abstract In the last decades, Periodontal Regeneration has been one of the most discussed topics in Periodontics, attracting the attention of researchers and clinicians. This can be justified by the evident and continuous progress observed in the field, characterized by a better understanding of the biological mechanisms involved, significant improvement of operative and technical principles, and the emergence of a wide range of biomaterials available for this purpose. Together, these aspects put the theme much in evidence in the search for functional and esthetic therapeutic solutions for periodontal tissue destruction. Despite the evident evolution, periodontal regeneration may be challenging and require the clinician to carefully evaluate each case before making a therapeutic decision. With a critical reassessment of the clinical and preclinical literature, the present study aimed to discuss the topic to answer whether Periodontal Regeneration is still a goal in clinical periodontology. The main aspects involved in the probability of success or failure of regenerative approaches were considered. A greater focus was given to intrabony and furcation defects, clinical conditions with greater therapeutic predictability. Aspects such as more appropriate materials/approaches, long-term benefits and their justification for a higher initial cost were discussed for each condition. In general, deep intrabony defects associated with residual pockets and buccal/lingual class II furcation lesions have predictable and clinically relevant results. Careful selection of the case (based on patient and defect characteristics) and excellent maintenance are essential conditions to ensure initial and long-term success.

Effect of two corticotomy protocols on periodontal tissue and orthodontic movement

Abstract Objective To compare two corticotomy surgical protocols in rats to verify whether they alter conventional orthodontic movement. Methodology Sixty Wistar rats were divided into three groups - orthodontic movement (CG), orthodontic movement and corticotomy (G1) and orthodontic movement with corticotomy and decortication (G2) - and euthanized after 7 and 14 days. Tooth movement (mm), bone volume fraction and bone volume ratio to total volume (BV/TV), and bone mineral density (BMD) were evaluated by micro-CT. The total amount of bone was measured in square millimeters and expressed as the percentage of bone area in the histomorphometry. The number of positive TRAP cells and RANK/RANKL/OPG interaction were also investigated. Results Day 14 showed a statistically significant difference in orthodontic tooth movement in CG compared with G1 (7.52 mm; p=0.009) and G2 (7.36 mm; p=0.016). A micro-CT analysis revealed a difference between CG, G1 and G2 regarding BV/TV, with G1 and G2 presenting a lower BV/TV ratio at 14 days (0.77 and 0.73 respectively); we found no statistically significant differences regarding BMD. There was a difference in the total amount of bone in the CG group between 7 and 14 days. At 14 days, CG presented a significantly higher bone percentage than G1 and G2. Regarding TRAP, G2 had more positive cells at 7 and 14 days compared with CG and G1. Conclusion Corticotomy accelerates orthodontic movement. Decortication does not improve corticotomy efficiency.

Evaluation of physicochemical properties of root-end filling materials using conventional and Micro-CT tests

Abstract Objective To evaluate solubility, dimensional stability, filling ability and volumetric change of root-end filling materials using conventional tests and new Micro-CT-based methods. Material and Methods Solubility (loss of mass) after 7 and 30 days, and dimensional stability (in mm) were evaluated in accordance with Carvalho-Junior, et al. 7 (2007). The filling ability and volumetric change (in mm3) were evaluated by Micro-CT (Bruker-MicroCT, Kontich, Belgium) using resin models with cavities 3 mm deep and 1 mm in diameter. The cavities were filled with materials to evaluate filling ability, and then scanned by Micro-CT. After 7 and 30 days immersed in distilled water, the filled cavities were scanned again to evaluate the volumetric change. MTA Angelus (MTA), Biodentine (BIO) and zinc oxide-eugenol cement (ZOE) were evaluated. Data were submitted to analysis of variance (ANOVA) and Tukey's test with 5% significance level. Results The results suggested correlated or complementary data between the proposed tests. At 7 days, BIO showed higher solubility and at 30 days, showed higher volumetric change in comparison with MTA (p<0.05). With regard to volumetric change, the tested materials were similar (p>0.05) at 7 days. At 30 days, they presented similar solubility. BIO and MTA showed higher dimensional stability than ZOE (p<0.05). ZOE and BIO showed higher filling ability (p<0.05). Conclusions ZOE presented a higher dimensional change, and BIO had greater solubility after 7 days. BIO presented filling ability and dimensional stability, but greater volumetric change than MTA after 30 days. Micro-CT can provide important data on the physicochemical properties of materials complementing conventional tests.

Suppressor of cytokine signaling 1 expression during LPS-induced inflammation and bone loss in rats

Abstract This study aimed to characterize the dynamics of suppressor of cytokine signaling (SOCS1) expression in a rat model of lipopolysaccharide-induced periodontitis. Wistar rats in the experimental groups were injected three times/week with LPS from Escherichia coli on the palatal aspect of the first molars, and control animals were injected with vehicle (phosphate-buffered saline). Animals were sacrificed 7, 15, and 30 days after the first injection to analyze inflammation (stereometric analysis), bone loss (macroscopic analysis), gene expression (qRT-PCR), and protein expression/activation (Western blotting). The severity of inflammation and bone loss associated with LPS-induced periodontitis increased from day 7 to day 15, and it was sustained through day 30. Significant (p < 0.05) increases in SOCS1, RANKL, OPG, and IFN-γ gene expression were observed in the experimental group versus the control group at day 15. SOCS1 protein expression and STAT1 and NF-κB activation were increased throughout the 30-day experimental period. Gingival tissues affected by experimental periodontitis express SOCS1, indicating that this protein may potentially downregulate signaling events involved in inflammatory reactions and bone loss and thus may play a relevant role in the development and progression of periodontal disease.

Comparison of two different methods for detecting periodontal pathogenic bacteria

Aim: To perform a comparative analysis between two methods for detecting Porphyromonas gingivalis, Tannerella forsythia and Porphyromonas endodontalis in periodontal plaque samples. Methods: The study sample consisted of twenty systemically healthy patients showing generalized chronic periodontitis. The subgingival samples for microbiological analysis were collected before (baseline) and 60 days after a basic periodontal therapy from 30 non-adjacent affected sites (Probing Depth (PD): 5-7 mm, Clinical Attachment Loss (CAL) ≥ 5 mm, positive for Bleeding on Probing (BOP)). Microbiological analysis was performed by PCR and qPCR. To allow a comparative analysis between both methods, qPCR was divided in three different scores (score 2: presence of more than 100 bacteria; score 1: presence of 10-100 bacteria, and score 0: absence of bacteria), in accordance to DNA quantity, while for PCR two scores were assigned: presence or absence of bacteria. Results: qPCR demonstrated higher sensitivity in the detection of these pathogens compared with PCR when scores 1 and 2 were considered positive. However, when only score 2 was considered positive, PCR and qPCR showed better agreement. Conclusions: qPCR demonstrated higher sensitivity than conventional PCR for detection of low numbers of microorganisms and can be useful for the quantification of periodontopathogens. (AU)

Analysis of polymorphisms in Interleukin 10, NOS2A, and ESR2 genes in chronic and aggressive periodontitis

Abstract The objective of this study was to investigate the association between single nucleotide polymorphisms (SNPs) in the IL10, NOS2A, and ESR2 genes and chronic periodontitis (CP) and aggressive periodontitis (AgP). Three groups of patients underwent periodontal and radiographic evaluations: CP (n = 61), AgP (n = 50), and periodontally healthy (control group=61). Genomic DNA was extracted from oral epithelial cells and used for genotyping by real-time polymerase chain reaction using TaqMan® probes. The investigated SNPs were: -1087G > A, -819C > T and -592C > A in the IL10; +2087G > A in the NOS2A, and +1730G > A in the ESR2 gene. Differences in genotype and allele frequencies of each polymorphism and some individual characteristics were analyzed using the chi-square test and multivariate logistic regression analysis. Analysis of SNPs and haplotypes in the IL10 and SNP in the ESR2 gene did not present any significant association with AgP or CP. The +2087G allele of the NOS2A gene tended to be significantly associated with periodontal disease. Patients carrying the genotype +2087GG in the NOS2A gene were genetically protected against the development of CP (p = 0.05; OR = 0.44; 95%CI = 0.20-0.95). This result showed greater significance when patients with AgP and CP were combined (total PD) (p = 0.03; OR = 0.46; 95%CI = 0.23-0.92). In conclusion, the studied Brazilian population had a significantly higher frequency of the GG genotype for the +2087 SNP in the NOS2A gene in individuals without periodontitis, although statistical significance was not maintained after multiple logistic regression.

Desenvolvimento do germe dentário e do palato em fetos de camundongos sob o efeito da Sinvastatina / Development of the tooth germ and palate in mouse embryos under effect of Sinvastatin

Introdução: As estatinas causaram uma revolução na prevenção e no tratamento do colesterol alto, porém é contraindicada no primeiro trimestre da gravidez, pois podem causar má formação no feto, no sistema nervoso central e nos membros. Objetivo: Verificar os efeitos da Sinvastatina na formação do palato e no desenvolvimento dos germes dentários dos primeiros molares superiores e inferiores. Material e Método: Para o acasalamento, foram utilizados 14 camundongos fêmeas e quatro machos; o dia 'zero' da gestação foi identificado pelo plug vaginal após acasalamento. As fêmeas prenhes foram divididas em Grupos I e III - receberam 10 mg/kg solução salina em três semanas antes do acasalamento e a partir do acasalamento até o 14.º dia de prenhez, respectivamente. Grupos II e IV receberam 10 mg/kg de Sinvastatina, no período de três semanas antes do acasalamento e a partir do acasalamento até o 14.º dia de prenhez, respectivamente. Resultado: A análise histológica dos fetos dos Grupos I, II, III e IV mostrou o palato fusionado na linha mediana do processo palatino. Os germes dentários dos primeiros molares dos Grupos II e IV apresentaram um desenvolvimento atrasado quando comparados aos Grupos I e III, porém, todos estavam nas etapas de capuz e campânula. Conclusão: As análises histológica e estatística mostraram que os fetos apresentaram palato fusionado na linha média de fusão do processo palatino e os germes dentários dos Grupos II e IV mostraram-se com formas indefinidas e contornos irregulares. Este estudo preliminar mostrou que a Sinvastatina pode ocasionar alterações morfológicas nos germes dentários.

Introduction: The statins have been strongly used for the prevention and treatment of high cholesterol, but are contraindicated in the first trimester of pregnancy because they may cause fetal malformation, affecting the central nervous system and the limbs. Objective: To investigate the effects of simvastatin in palate formation and development of tooth germs of the first upper and lower molars. Material and Method: Fourteen female and 4 male mice were used for breeding. The day "zero" of pregnancy was identified by vaginal plug after mating. The pregnant females were divided into four groups. Animals from Groups I and III received daily 10 mg /kg of saline three weeks before mating and from mating through day 14 of pregnancy, respectively. Animals from Groups II and IV received daily 10 mg/kg of simvastatin in the 3 weeks prior to mating and from mating through day 14 of pregnancy, respectively. Result: Histological evaluation of fetuses from Groups I to IV showed fused palate. The first molar tooth germs from Groups II and IV showed up with undefined forms and jagged edges suggesting a slower development compared to Groups I and III, although all the samples were at the bell or hood development stages. . Conclusion: This preliminary study showed that simvastatin does not affect palate fusion but can cause morphologic alterations in tooth germs of fetuses during gestation.

A utilização do enxerto ósseo autógeno para tratamento de lesão de furca Grau II / Utilization of autogenous bone grafts to treat class II furcation

A destruição do tecido ósseo e do ligamento periodontal como consequênciada doença periodontal pode gerar defeitos anatômicos na regiãode furca. O tratamento destas lesões é um grande desafio para o clínico,pois esta área possui acesso limitado para os instrumentais de raspagem,tornando difícil a remoção eficiente do biofilme dental e do cálculo dassuperfícies radiculares. Para o planejamento adequado da terapêutica a serutilizada, uma série de fatores devem ser levados em consideração visandoa obtenção de sucesso imediato e a longo prazo do caso. A terapiacirúrgica com a utilização de enxertos pode ser uma opção viável em casosde lesões de furca Grau II visando o fechamento da lesão e maior estabilidadeperiodontal. O objetivo deste artigo foi relatar um caso clínicoonde foi realizada uma abordagem cirúrgica simplificada com a utilizaçãoapenas de enxerto autógeno para o tratamento de um dente com lesãode furca Grau II. Após 12 meses de pós-operatório houve aumento nonível de inserção clínica e diminuição da profundidade de sondagem comconsequente fechamento total da lesão de furca.

Modulation of host cell signaling pathways as a therapeutic approach in periodontal disease

Recently, new treatment approaches have been developed to target the host component of periodontal disease. This review aims at providing updated information on host-modulating therapies, focusing on treatment strategies for inhibiting signal transduction pathways involved in inflammation. Pharmacological inhibitors of MAPK, NFκB and JAK/STAT pathways are being developed to manage rheumatoid arthritis, periodontal disease and other inflammatory diseases. Through these agents, inflammatory mediators can be inhibited at cell signaling level, interfering on transcription factors activation and inflammatory gene expression. Although these drugs offer great potential to modulate host response, their main limitations are lack of specificity and developments of side effects. After overcoming these limitations, adjunctive host modulating drugs will provide new therapeutic strategies for periodontal treatment.

Morphometric study of the root anatomy in furcation area of mandibular first molars

Furcation involvement in periodontal disease has been a challenge for the dentist. OBJECTIVE: The aim of this study was to investigate root dimensions in the furcation area of 233 mandibular first molars. MATERIAL AND METHODS: Digital photomicrographs were used to obtain the following measurements on the buccal and lingual surfaces of each tooth: root trunk height (RT), horizontal interadicular distance obtained 1 mm (D1) and 2 mm (D2) below the fornix and interadicular angle (IA). RESULTS: Mean± standard deviation of buccal and lingual furcation measurements were, respectively, 1.37±0.78 mm and 2.04±0.89 mm for RT; 0.86±0.39 mm and 0.71±0.42 mm for D1; 1.50±0.48 mm and 1.38±0.48 mm for D2; 41.68±13.20° and 37.78±13.18° for IA. Statistically significant differences were found between all measured parameters for buccal and lingual sides (p<0.05, paired t test). CONCLUSIONS: In conclusion, the lingual furcation of mandibular first molars presented narrower entrance and longer root trunk than the buccal furcation, suggesting more limitation for instrumentation and worse prognosis to lingual furcation involvements in comparison to buccal lesions.

Combination of orthodontic movement and periodontal therapy for full root coverage in a miller class iii recession: a case report with 12 years of follow-up

One of the main purposes of mucogingival therapy is to obtain full root coverage. Several treatment modalities have been developed, but few techniques can provide complete root coverage in a class III Miller recession. Thus, the aim of this case report is to present a successful clinical case of a Miller class III gingival recession in which complete root coverage was obtained by means of a multidisciplinary approach. A 17-year-old Caucasian female was referred for treatment of a gingival recession on the mandibular left central incisor. The following procedures were planned for root coverage in this case: free gingival graft, orthodontic movement by means of alignment and leveling and coronally advanced flap (CAF). The case has been followed up for 12 years and the patient presents no recession, no abnormal probing depth and no bleeding on probing, with a wide attached gingiva band. A compromised tooth with poor prognosis, which would be indicated for extraction, can be treated by orthodontic movement and periodontal therapy, with possibility of 100% root coverage in some class III recessions.

Um dos principais objetivos da terapia mucogengival é atingir a cobertura completa da raiz. Diversas modalidades de tratamento têm sido desenvolvidas, mas poucas técnicas podem obter a cobertura total da raiz em uma recessão gengival classe III de Miller. Assim, o objetivo deste relato é apresentar um caso de sucesso clínico de uma recessão gengival classe III de Miller na qual foi obtida a cobertura completa da raiz por meio de uma abordagem multidisciplinar. Uma jovem de 17 anos sexo feminino, leucoderma, foi encaminhada para tratamento de uma recessão gengival no incisivo central inferior esquerdo. Para a cobertura radicular foi planejado: enxerto gengival livre, movimento ortodôntico por meio de alinhamento e nivelamento e retalho reposicionado coronariamente (CAF). Este caso tem sido acompanhado por 12 anos e o paciente apresenta ausência de recessão, sem profundidade de sondagem anormal e sem sangramento à sondagem com ampla faixa de gengiva inserida. Dentes comprometidos e com mau prognóstico, que seriam extraídos em muitos casos, podem ser tratados por meio de movimento ortodôntico e terapia periodontal. 100% de cobertura da raiz é possível e pode ser conseguida em alguns casos de recessão gengival classe III.

Associação de prótese fixa, implantes e estética periodontal para reabilitação de pacientes parcialmente edêntulos / Association of fixed partial prosthesis, dental implants, and periodontal aesthetic procedures for rehabilitation of partially edentulous patients

A doença periodontal é uma doença inflamatória crônica que resulta na destruição dos tecidos de suporte com consequente perda dental. A substituição dos dentes perdidos por restaurações implantossuportadas tem demonstrado ser um método de tratamento altamente previsível com bom prognóstico em longo prazo. Contudo, algumas sequelas da perda dentária inviabilizam a instalação de implantes osseointegrados em posição ideal, sendo, neste caso, necessários procedimentos regenerativos para tornar possível este tipo de reabilitação. Procedimentos menos invasivos, como próteses convencionais, surgem como uma opção terapêutica para reabilitação de casos em que não há estrutura óssea suficiente para implantes e não há aceitação de procedimentos invasivos por parte dos pacientes. Sendo assim, este trabalho teve como objetivo apresentar a resolução de uma reabilitação por meio de tratamento não invasivo e multidisciplinar. A paciente, gênero feminino, compareceu a clínica da faculdade apresentando próteses fixas mandibulares mal adaptadas bilateralmente, lesões endodônticas, recessão gengival nos dentes pilares e sensibilidade dentinária. Para a adequada resolução deste caso foi proposto à associação de implantes osseointegrados, prótese parcial fixa, exodontia e procedimentos periodontais estéticos, com a utilização de enxerto de tecido conjuntivo subepitelial. Após dois anos de pós-operatório, a paciente mostrou satisfação estética e mastigatória. Com base no caso apresentado, este trabalho discutiu os diversos fatores que podem afetar a escolha de uma determinada modalidade de tratamento, para a reabilitação de espaços edêntulos unitários.

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.

Effect of platelet-rich plasma on healing of class III furcation defects treated with autogenous bone grafting and guided tissue regeneration: a histomorphometric study in dogs / Efeito do plasma rico em plaquetas na reparação de lesões de furca classe III tratadas com enxerto ósseo autógeno e regeneração tecidual guiada: estudo histomorfométrico em cães

Objetivo: O objetivo deste estudo foi avaliar histologicamente os efeitos do plasma rico em plaquetas (PRP), quando usado em combinação com enxerto ósseo autógeno e membrana bioabsorvível (Resolut®) no tratamento de defeitos de furca Classe III em cães. Material e método: Cinco cães foram usados neste estudo. Defeitos de furca classe III (5 mm de altura e de profundidade) foram criados cirurgicamente no terceiro pré-molar inferior de ambos os lados. Nove semanas após a primeira cirurgia, os terceiros pré-molares foram tratados com raspagem e alisamento radicular e cada defeito recebeu um dos seguintes tratamentos: Enxerto ósseo autógeno + membrana (grupo C) ou PRP + enxerto ósseo autógeno + membrana (grupo T). Após um período de cicatrização de 90 dias, os animais foram sacrificados. Processamento histológico de rotina e coloração com hematoxilina e eosina e tricrômico de Masson foram realizados para determinar o efeito dos tratamentos na regeneração dos tecidos periodontais. Os dados foram analisados pelo teste T2 de Hotelling (p < 0,05). Resultado: A análise histomorfométrica da área de furca não mostrou nenhuma diferença estatisticamente significativa entre os grupos C e T. Os dois grupos de tratamento demonstraram resultados regenerativos semelhantes, com os defeitos de furca parcialmente preenchidos e a regeneração periodontal foi limitada à marca experimental apical das lesões. (p > 0,05). Conclusão: Dentro dos limites deste estudo, concluiu-se que o uso de PRP não melhorou a regeneração periodontal em defeitos de furca classe III tratados com enxerto ósseo autógeno e membrana bioabsorvível.

Objective: The purpose of this study was to evaluate the effects of the platelet-rich plasma (PRP) when used in combination with autogenous bone graft and bioabsorbable membrane (Resolut®) in the treatment of Class III furcation defects in dogs. Material and method: Class III furcation defects (5 mm in height and in depth) were surgically created in the mandibular third premolars of five mongrel dogs. After nine weeks, the lesions were treated with scaling and root planning and each defect received one of the following treatments: autogenous bone graft + membrane (group C) or PRP + autogenous bone graft + membrane (group T). After a healing period of 90 days, the animals were sacrificed. Routine histological processing and staining with hematoxilyn and eosin and Masson trichrome were performed and a histomorphometric analysis determined the effect of the treatments on periodontal tissue regereneration. Data were analyzed by Hotelling's T-squared (p < 0.05). Result: No statistically significant difference between C and T groups was observed by the histomorphometric analysis of the furcation area. Both treatment groups demonstrated similar regenerative results with the furcation defects partially filled and periodontal regeneration limited to the experimental notches of the lesions. (p > 0.05). Conclusion: According to the present results, PRP does not enhance the periodontal regeneration in class III furcation defects treated with autogenous bone graft and bioabsorbable membrane.

Importância do tratamento estético periodontal na reabilitação protética / Importance of aesthetic periodontal treatment on prosthetic rehabilitation: a case report

A recessão gengival é uma deformidade comum que afeta um grande número de indivíduos e está frequentemente associada com comprometimento estético e com hipersensibilidade dentinária. Várias técnicas cirúrgicas têm sido propostas ao longo dos anos para lidar com este problema. Desde 1950, enxertos livres e enxertos gengivais pediculados têm sido bastante utilizados para o tratamento de recessão gengival. Contudo, com a classificação de Miller, proposta em 1985 e com o surgimento de outras técnicas utilizando enxerto de tecido conjuntivo subepitelial para recobrimento de raiz, os resultados se tornaram mais previsíveis, especialmente no que diz respeito a recessões Classe I e II, ou seja, na ausência de perda óssea interproximal. Este artigo relata a importância do tratamento estético periodontal na reabilitação protética de um paciente portador de recessão gengival Classe I de Miller com 3 mm de extensão vertical no canino superior direito. O plano de tratamento consistiu em recobrimento radicular utilizando enxerto de tecido conjuntivo subepitelial (SCTG) associado com deslocamento coronário do retalho e confecção de novas próteses.

Dimensões das furcas de primeiros pré-molares superiores e sua relação com curetas periodontais / Furcations entrance dimensions of first maxillary premolars and its relation with periodontal curettes

O objetivo deste estudo foi avaliar comparativamente as dimensões das entradas das furcas mesial e distal de primeiros pré-molares superiores extraídos e compará-las com as dimensões das lâminas de diversos tipos de curetas. Foram mensuradas, com paquímetro digital (Digital-Cal Plus, Brown & Sharpe, Co. Ltda.), as distâncias de tronco radicular (TR) a 1 mm (D1) e 2 mm (D2) abaixo da entrada da furca. As curetas selecionadas foram: Gracey, Mini Gracey, Pádua Lima (PL) e Goldman Fox 4 (todas da marca Millenium); obtendo-se as seguintes medidas tanto pela face coronária quanto lateral: DT - distância total do comprimento da lâmina ativa; DI - largura da extremidade da ponta ativa; DM - largura da porção média da ponta ativa. Os dados TR, D1 e D2 apresentaram distribuições normais, sendo analisados pelo teste paramétrico t pareado. Diferença estatística significante foi encontrada na região do tronco radicular (TR) mesial de ambos os primeiros pré-molares, mostrando média das mensurações maior que a distal. Foram obtidas médias e desvio-padrão das curetas, sendo que tanto Gracey quanto Mini Gracey apresentaram mensurações médias compatíveis com a entrada da furca mais estreita (D1 - 1 mm). A Goldman Fox 4 apresentou adaptação apenas nas faces mesiais, e a Pádua Lima não mostrou acesso a nenhuma das faces. Conclui-se que a abertura da furca é estreita (D1); o lado mesial do tronco radicular (TR) tem mensurações médias maiores que o lado distal; as curetas Gracey e Mini Gracey apresentaram-se compatíveis para ambas as faces, mesial e distal dos primeiros pré-molares superiores estudados.

Detection of the single nucleotide polymorphism (rs2227307) in the human interleukin 8 gene using a different PCR-RFLP assay / Detecção do polimorfismo de base única (rs2227307) no gene interleucina 8 humano usando PCR-RFLP

Interleukin 8 (IL-8) is a chemokine that acts as a potent chemoattractant for neutrophils. Single nucleotide polymorphisms (SNPs) in the human IL8 gene have been investigated in many disease association studies. We have developed a different PCR-RFLP (Polymerase Chain Reaction - Restriction Fragment of Length Polymorphism) assay for genotyping the SNP (rs2227307) in the IL8 gene. This method was used for typing 147 white healthy Brazilian individuals, whose DNA was obtained from buccal epithelial cells and extracted with phenol: chloroform: isoamyl alcohol. Genomic DNA was amplified by PCR using a conventional thermal cycler. The PCR products (573 bp) were submitted to RFLP reactions. The RFLP fragments were analyzed in a 4% agarose gel stained with ethidium bromide. The genotype distribution observed in this study was consistent with the assumption of Hardy-Weinberg equilibrium and was similar (p=0.30) to those reported for other white populations in the SNP Database of the National Center for Biotechnology Information (NCBI). Because the PCR-RFLP method presented here was efficient, low cost, reproducible and convenient for laboratories with a limited level of technology worldwide, it should be useful for genotyping in case-control association or population genetic studies.

A Interleucina 8 é uma quimiocina com potente ação quimioatrativa para neutrófilos. Polimorfismos de base única (SNPs) no gene humano IL8 têm sido investigados em vários estudos de associação com doenças. Um método diferente de PCR-RFLP para genotipagem do SNP (rs2227307) do gene IL8 foi desenvolvido pelo nosso grupo. Esse método foi utilizado para genotipar 147 indivíduos brasileiros brancos saudáveis que tiveram seu DNA obtido de células da mucosa oral e extraído com fenol:clorofórmio:álcool isoamílico. DNA genômico foi amplificado por PCR usando um termociclador convencional, e a seguir os produtos da PCR (573 pb) foram submetidos a reações de RFLP. Os produtos de RFLP foram analisados em gel de agarose 4% impregnado com brometo de etídio. A distribuição do genótipo observado neste estudo foi consistente com o equilíbrio de Hardy-Weinberg e foi similar (p=0,30) ao reportado em outras populações brancas no banco de dados de SNPs do National Center for Biotechnology Information (NCBI). Este novo método de PCR-RFLP apresentado neste estudo foi eficiente, de baixo custo, reprodutível e conveniente para laboratórios com tecnologia limitada, podendo ser útil para utilização em estudos de genética de populações ou de associação com doenças (tipo caso-controle).

Treatment of gingival recession with collagen membrane and DFDBA: a histometric study in dogs

In a previous study, we evaluated the findings related to the use of resorbable collagen membranes in humans along with DFDBA (demineralized freeze-dried bone allograft). The aim of this subsequent study was to histometrically evaluate in dogs, the healing response of gingival recessions treated with collagen membrane + DFDBA (Guided Tissue Regeneration, GTR) compared to a coronally positioned flap (CPF). Two types of treatment were randomly carried out in a split-mouth study. Group 1 was considered as test (GTR: collagen membrane + DFDBA), whereas Group 2 stood for the control (only CPF). The dogs were given chemical bacterial plaque control with 0.2 percent chlorhexidine digluconate during a 90-day repair period. Afterwards, the animals were killed to obtain biopsies and histometric evaluation of the process of cementum and bone formation, epithelial migration and gingival level. A statistically significant difference was found between groups with a larger extension of neoformed cementum (GTR = 32.72 percent; CPF = 18.82 percent; p = 0.0004), new bone (GTR = 23.20 percent; CPF = 09.90 percent; p = 0.0401) and with a smaller area of residual gingival recession in the test group (GTR = 50.69 percent; CPF = 59.73 percent; p = 0.0055) compared to the control group. The only item assessed that showed no statistical difference was epithelial proliferation on the root surface, with means of 15.14 percent for the GTR group and 20.34 percent for the CPF group (p = 0.0890). Within the limits of this study we concluded that the treatment of gingival recession defects with GTR, associating collagen membrane with DFDBA, showed better outcomes in terms of a larger extension of neoformed cementum and bone, as well as in terms of a smaller proportion of residual recessions.

Transmission of Aggregatibacter actinomycetemcomitans between Brazilian women with severe chronic periodontitis and their children

This study evaluated the transmission of Aggregatibacter actinomycetemcomitans (Aa) in women with severe chronic periodontitis and their children. Thirty women (mean age = 36.1±6.0 years) who were mothers of at least one child aged 7 to 16 years were enrolled. In order to investigate mother-child transmission of Aa, the children were also evaluated when their mothers were colonized by the bacterium. Subgingival plaque samples of each woman were collected from 3 sites (mean probing depth of 7.3±1.2 mm and mean clinical attachment level of 7.9±1.5 mm) and pooled in reduced transport fluid (RTF). These samples were processed, inoculated onto TSBV-agar selective medium and incubated at 37°C in microaerophilic atmosphere for 5 days. Aa was identified on the basis of colony morphology, Gram staining, catalase and oxidase reactions. Aa was found in 8 out of 30 women. Therefore, 8 children from these women (mean age= 12 ± 3.7 years) were evaluated, but Aa was found only in 2 of them. Aa strains of the two mother-child pairs were evaluated by arbitrarily-primed polymerase chain reaction (AP-PCR), although it was not found similarity between the amplitypes of each pair. No Aa transmission was found between Brazilian women with severe chronic periodontitis and their children.

Este estudo avaliou a transmissão de Aggregatibacter actinomycetemcomitans (Aa) entre mulheres com periodontite crônica severa e seus filhos. A amostra constituiu-se de 30 mulheres com idade média de 36,1 ± 6,0 anos, mães de filhos com idade entre 7 e 16 anos. Apenas crianças cujas mães haviam sido colonizadas por Aa foram incluídas. Amostras de placa dentária subgengival foram colhidas de três sítios com profundidade de sonagem média de 7,3 ± 1,2 mm e perda de inserção clínica média de 7,9 ±1,5 mm e agrupadas em fluido de transporte reduzido (RTF). Estas amostras foram processadas e semeadas em meio seletivo ágar TSBV e incubados a 37ºC em atmosfera de microaerofilia por 5 dias. Aa foi identificado baseado na morfologia colonial, coloração de Gram e testes da catalase e oxidase. Aa foi detectado em 8 das 30 mulheres . Assim, 8 filhos destas mulheres, com idade média de 12 ± 3,7 anos foram investigados, mas Aa foi detectado em apenas 2 deles. Cepas de Aa dos 2 pares de mães e filhos foram submetidos a análise pela técnica de reação em cadeia de polimerase usando primers arbitrários (AP-PCR), mas os amplitipos de cada par não demonstraram similaridade. Portanto, não foi encontrada transmissão de Aa entre mulheres brasileiras com periodontite crônica severa e seus filhos.