El papel del óxido nítrico en la modulación del proceso inflamatorio de la enfermedad periodontal

Nitric oxide (NO) is a free radical with participation in almost all physiologic host processes; however, in high concentrations it may damage the tissues. Its immunoregulatory action is present in the inflammation and in auto-immune mechanisms, being intensively studied in the medical area. Recently, some studies have also reported that NO could play a role as etiopathogenic factor of the periodontal disease, which shows inflammatory and multifactorial course. Due to beneficial or damage effects of NO, according to its concentrations, some studies have been focused in the evaluation of inhibitor of NO-Synthase (NOS) as therapeutic agents in inflammatory processes. In this context, the aim of this study was to report the role of NO and NOS inhibition in the periodontal disease modulation process. In conclusion, it could be suggested that NO seems to play an essential role in evolution of inflammatory periodontal disease, and that the NOS inhibition may be considered as a promising therapeutic in modulation of inflammatory process.

Conhecimento de cárie dental e doença periodontal de professores do ensino fundamental segundo o tipo de instituição (pública ou privada)

Aim: observe the knowledge of dental caries and periodontal disease of primary schoolteachers, according to type of institution (public and private) from Araraquara city. methodology: for that participants were 113 teachers from public schools and 57 from private schools. The instrument of analysis was based on a questionnaire with closed and open questions concerning the etiology, prevention and development of dental caries and periodontal disease. Results: 97,3% of public ́s schoolteachers and 91,2% of private ́s schoolteachers answered that they knows what is dental caries, but they didn ́t answer correctly about the caries etiology as being multifactorial and about methods of prevention. Both of schoolteachers (public and private) had more sucessful when answered about bacterial plaque than periodontal disease and yours manifestation. Conclusion: the dental knowledge of schoolteachers in public and private school was evaluated and limited educational programs should be directed to both public and private schoolteachers, in order to increase the level of dental knowledge of them, so that they can act as educational agents with the children.

Occurrence of socransky red complex in pregnant women with and without periodontal disease

Purpose: To verify the presence of Socransky Red Complex (Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia) and P. intermedia using polymerase chain reaction (PCR) in periodontally healthy pregnant women and pregnant women with periodontal disease, as well as its relation to arterial blood pressure and capillary glycaemia.Materials and Methods: This case control study included 86 pregnant women, including 50 pregnant women with healthy periodontium, 27 with gingivitis and 9 with periodontitis. Arterial blood pressure and glycaemia were evaluated and recorded. Clinical specimens from the gingival crevice or periodontal pockets were gathered with sterile absorbent paper cones. DNA extraction was accomplished using the Easy-DNA Kit test and the presence of bacteria was detected by PCR with primers and specific probes for each microorganism.Results: The arterial pressure of all pregnant women was found to be within normal levels and 51% presented with hyperglycaemia, these two variables were not associated with periodontal conditions and/or presence of microorganisms. Socransky Red Complex was not present in pregnant women with healthy periodontium; however, it was present in pregnant women with gingivitis (3.7%) and in a higher percentage of pregnant women with periodontitis (33.3%).Conclusion: Socransky Red Complex was found only in cases of periodontal diseases and is not related to blood pressure and/or high levels of blood glucose.

Highlights in peptide nanoparticle carriers intended to oral diseases

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

Effect of root canal status on periodontal healing after surgical injury in dogs.

This study was carried out to observe if the status of the root canal might influence the healing process of surgically prepared experimental periodontal lesions. Forty tooth roots from four dogs were divided into four different groups: a) root canals with vital pulps, b) root canals open to the oral environment, c) root canals infected and filled with zinc oxide eugenol cement, and d) root canals infected and filled with calcium hydroxide. By means of a surgical intervention, a cavity was prepared in the medium portion of the roots. Six months later, the specimens were removed and prepared for histological analysis. The results, which were submitted to statistical analysis, showed that the status of the root canals influenced the healing process of the experimental periodontal lesions. In the groups where the root canals were filled, calcium hydroxide gave the best results. In the group with root canals left open to the oral environment, resorption of the dentin of the experimental cavities, was the most obvious observation. However, it did not prevent the repair process, only slowed it down.

The effect of blue light on periodontal biofilm growth in vitro

We have previously shown that blue light eliminates the black-pigmented oral bacteria Porphyromonas gingivalis, Prevotella intermedia, Prevotella nigrescens, and Prevotella melaninogenica. In the present study, the in vitro photosensitivity of the above black-pigmented microorganisms and four Fusobacteria species (Fusobacterium nucleatum ss. nucleatum, F. nucleatum ss. vincentii, F. nucleatum ss. polymorphum, Fusobacterium periodonticum) was investigated in pure cultures and human dental plaque suspensions. We also tested the hypothesis that phototargeting the above eight key periodontopathogens in plaque-derived biofilms in vitro would control growth within the dental biofilm environment. Cultures of the eight bacteria were exposed to blue light at 455 nm with power density of 80 mW/cm(2) and energy fluence of 4.8 J/cm(2). High-performance liquid chromatography (HPLC) analysis of bacteria was performed to demonstrate the presence and amounts of porphyrin molecules within microorganisms. Suspensions of human dental plaque bacteria were also exposed once to blue light at 455 nm with power density of 50 mW/cm(2) and energy fluence of 12 J/cm(2). Microbial biofilms developed from the same plaque were exposed to 455 nm blue light at 50 mW/cm(2) once daily for 4 min (12 J/cm(2)) over a period of 3 days (4 exposures) in order to investigate the cumulative action of phototherapy on the eight photosensitive pathogens as well as on biofilm growth. Bacterial growth was evaluated using the colony-forming unit (CFU) assay. The selective phototargeting of pathogens was studied using whole genomic probes in the checkerboard DNA-DNA format. In cultures, all eight species showed significant growth reduction (p < 0.05). HPLC demonstrated various porphyrin patterns and amounts of porphyrins in bacteria. Following phototherapy, the mean survival fractions were reduced by 28.5 and 48.2 % in plaque suspensions and biofilms, respectively, (p < 0.05). DNA probe analysis showed significant reduction in relative abundances of the eight bacteria as a group in plaque suspensions and biofilms. The cumulative blue light treatment suppressed biofilm growth in vitro. This may introduce a new avenue of prophylactic treatment for periodontal diseases.

Efeito concomitante da doença periodontal induzida e movimentação ortodôntica em ratos submetidos à inalação da fumaça de cigarro: estudo histomorfométrico

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Experimental periodontal disease treatment by subgingigval irrigation with tetracycline hidrochloride in rats

Objective: The aim of this study was to compare subgingival irrigation with tetracycline hydrochloride (TTC-HCL) as adjunctive treatment to scaling and root planning (SRP) on induced periodontitis in rats. Material and Methods: In 60 rats, periodontal disease was ligature-induced at the mandibular left first molar. After 7 days, the ligature was removed and all animals were submitted to SRP, and divided into 2 groups according to the following treatment: C (n=30) – subgingival irrigation with 1 mL of saline; T (n=30) – subgingival irrigation with 1 mL of TTC-HCL (50 mg/mL). Ten animals in each group were euthanized at 7, 15 and 30 days posttreatment. The histometric values were statistically analyzed (p<0.05). Results: In the histometric analysis, at 7, 15 and 30 days, Group T (0.72±0.05 mm2, 0.57±0.14 mm2, 0.62±0.07 mm2), showed less bone loss (p<0.05) than Group C (1.35±0.25 mm2; 1.40±0.31 mm2; 1.29±0.27 mm2), respectively. Conclusions: Subgingival irrigation with TTC-HCL was an effective adjunctive treatment for periodontal disease induced in rats.

Avaliação da sensibilidade à insulina e concentração do cortisol salivar em gestantes com doença periodontal

Pós-graduação em Odontologia Preventiva e Social - FOA

Investigação da expressão de genes do metabolismo lipídico em pacientes com Diabetes Mellitus tipo 2, Dislipidemia e Doença Periodontal Crônica

Pós-graduação em Odontologia - FOAR

Análise farmacognóstica e atividade antibacteriana de extratos vegetais empregados em formulação para a higiene bucal

A utilização de extratos vegetais vem se tornando uma alternativa importante para a prevenção de doenças periodontais. Este trabalho objetivou desenvolver uma formulação de enxagüatório bucal, contendo, em associação, extratos hidroalcoólicos de Rosmarinus officinalis, Plantago major, Tabebuia impetiginosa, Achillea millefollium e Nasturtium officinale; avaliar sua composição farmacognóstica e sua atividade antibacteriana, como também da fórmula proposta. Foram realizados estudos de pré-formulação e análises farmacognósticas para as espécies vegetais. A atividade antibacteriana in vitro foi observada por meio dos métodos de difusão em disco de papel, por hole- plate e por template, frente a Staphylococcus aureus, Bacillus subtilis, Escherichia colik, Enterococcus faecalis e Pseudomonas aeruginosa. A concentração inibitória mínima (CIM) foi determinada por meio do método de macrodiluições sucessivas em caldo. Os resultados obtidos apresentaram-se de acordo com o histórico farmacognóstico das drogas estudadas. Todas as bactérias foram inibidas pelos extratos, observando-se que as espécies S. aureus e B. subtilis mostraram, aparentemente, maior sensibilidade. A CIM variou, em relação a sensibilidade de cada espécie bacteriana estudada, de 312,5 µL/mL a 1250 µL/mL para os extratos vegetais e de 625 µL/mL a 2500 µL/mL para o enxaguatório bucal. São necessários estudos complementares para a confirmação da eficácia deste produto e sua utilização na prevenção de doenças periodontais.

Presence of bacteria in dentinal tubules

This study demonstrated that a significant number of bacteria is present. in the radicular dentinal tubules of periodontally diseased human teeth. Ten periodontally diseased teeth were prepared and stained by Brown and Brenn technique for histological examination. Bacteria were detected in all teeth. It is suggested that bacteria may invade dentinal tubules exposed to periodontal pocket and are very hard to be eliminated by conventional mechanical and chemical periodontal therapy. Contaminated dentinal tubules of periodontally diseased teeth can thus act as active bacterial reservoirs to promote recolonization of mechanically treated root surfaces, which could interfere with the periodontal healing and progression of the disease.

Histometric analysis of ligature-induced periodontitis in rats: a comparison of histological section planes

The purpose of this study was to analyze the histometry of ligature-induced periodontitis in rats at different histological section depths. Sixteen male adult Wistar rats were randomly assigned to two groups: ligature and control. In the ligature group, rats received a sterile 4/0 silk ligature around the maxillary right 2nd molar. Thirty serial sections containing the 1st and 2nd molars, in which the coronal and root pulp, cementoenamel junction (CEJ) in the mesial side of the 2nd molar, interproximal alveolar bone and connective fiber attachment were clearly visible, were selected for histometric analysis. The histological sections were clustered in groups of 10 sections corresponding the buccal (B), central (C) and lingual (L) regions of the of periodontal tissue samples. The distance between the CEJ in the mesial side of the 2nd molar and the attached periodontal ligament fibers (CEJ-PL) as well as the distance between the CEJ and the alveolar bone crest (CEJ-BC) were determined. From CEJ-PL and CEJ-BC distances measured for each specimen, the measurements obtained in the B, L and C regions were recorded individually and together. Data were submitted to statistical analysis. Significant differences (p<0.001) were observed between the control and ligature groups regarding CEJ-PL (0.05 mm and 0.26 mm, respectively) and CEJ-BC (0.47 mm and 0.77 mm, respectively) measurements. Regarding the depth of the buccal, central and lingual planes, the means of CEJ-PL and CEJ-BC of both groups showed no statistically significant differences (p>0.05). In conclusion, the selection of 10 serial sections of the central region of periodontal tissue samples at any depth can be considered as representative for the evaluation of periodontal ligament fiber attachment and bone loss in ligature-induced periodontitis in rats.

O tabagismo como fator de risco para as doenças periodontais: aspectos microbiológicos

O fumo é considerado importante fator predisponente para muitas doenças, incluindo-se as periodontopatias. Desde que as doenças periodontais representam a inter-relação entre os fatores de virulência da microbiota subgengival sobre um hospedeiro susceptível, foi objetivo avaliar a freqüência de isolamento de três periodontopatógenos em indivíduos sadios e pacientes com doença periodontal, fumantes ou não, com níveis variados de higiene bucal; verificar a relação entre o número de microrganismos produtores de sulfeto de hidrogênio na placa subgengival de fumantes e não fumantes e sua condição clínica. Foram examinados 189 pacientes e indivíduos sadios, dos quais 60 foram selecionados para análise microbiológica. O índice de placa foi registrado de acordo com o índice de O'Leary e os espécimes de placa subgengival coletados e processados de acordo com SLOTS35 (1982). A identificação dos isolados foi obtida pelas suas características morfocelulares, morfocoloniais e bioquímico-fisiológicas. Verificou-se que a freqüência de isolamento dos bastonetes anaeróbios produtores de pigmento negro, Fusobacterium nucleatum e bactérias produtoras de sulfeto de hidrogênio foi similar entre fumantes e não fumantes, sendo mais elevada nos pacientes com doença periodontal. Já Actinobacillus actinomycetemcomitans foi isolado mais freqüentemente em sadios fumantes do que sadios não fumantes.

Antimicrobial effect of human serum on oral Fusobacterium nucleatum isolates from humans and monkeys

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