Systemic antibiotics increase microbiota pathogenicity and oral bone loss / 国际口腔科学杂志·英文版

Periodontitis is the most widespread oral disease and is closely related to the oral microbiota. The oral microbiota is adversely affected by some pharmacologic treatments. Systemic antibiotics are widely used for infectious diseases but can lead to gut dysbiosis, causing negative effects on the human body. Whether systemic antibiotic-induced gut dysbiosis can affect the oral microbiota or even periodontitis has not yet been addressed. In this research, mice were exposed to drinking water containing a cocktail of four antibiotics to explore how systemic antibiotics affect microbiota pathogenicity and oral bone loss. The results demonstrated, for the first time, that gut dysbiosis caused by long-term use of antibiotics can disturb the oral microbiota and aggravate periodontitis. Moreover, the expression of cytokines related to Th17 was increased while transcription factors and cytokines related to Treg were decreased in the periodontal tissue. Fecal microbiota transplantation with normal mice feces restored the gut microbiota and barrier, decreased the pathogenicity of the oral microbiota, reversed the Th17/Treg imbalance in periodontal tissue, and alleviated alveolar bone loss. This study highlights the potential adverse effects of long-term systemic antibiotics-induced gut dysbiosis on the oral microbiota and periodontitis. A Th17/Treg imbalance might be related to this relationship. Importantly, these results reveal that the periodontal condition of patients should be assessed regularly when using systemic antibiotics in clinical practice.

Efecto de los antagonistas de los receptores AT1 de la angiotensina II sobre la enfermedad periodontal inducida por inyecciones de lipopolisacáridos en ratas / Effect of ang II AT1 receptor antagonists, on periodontal disease induced by injections of lipopolysaccharide in rats

La Enfermedad Periodontal (EP) es una condición inflamatoria progresiva que afecta los tejidos que soportan y rodean a los dientes. Las endotoxinas bacterianas como los lipopolisacáridos (LPS), inducen una cascada inflamatoria causando resorción ósea mediante la producción y modulación de la red de citoquinas del tejido periodontal, del sistema RANK-RANKL-OPG y de la producción de especies reactivas del oxígeno (ERO). Siendo la vía final la activación del factor de transcripción NFκB para el control de la infección. Se sabe que el Sistema Renina Angiotensina (SRA) esta involucrado en la inflamación. Estas acciones pro-inflamatorias de la Ang II son producidas por la activación de NFkB mediante los receptores AT1, y por la generación de ERO. Nuestro objetivo fue determinar si la inhibición del receptor AT1 con el uso del valsartán reduciría la respuesta inmunitaria innata inflamatoria en un modelo de EP inducida por las inyecciones de LPS en la encía de las ratas. Nuestros resultados demuestran que el Valsartán disminuyó la leucocitosis sistémica, la movilidad dentaria, atenuó la pérdida de peso corporal de las ratas, disminuyó la formación de enzimas antioxidantes y NOS, redujo la producción y liberación de citocinas pro inflamatorias y aumentó las citocinas antinflamatorias, disminuyó la activación de p-p38, p-NFkB y la expresión de los receptores TLR4. El Valsartán también revirtió los efectos del LPS sobre la resorción ósea ya que disminuyó el número de osteoclastos, la expresión de los receptores RANK/RANKL/OPG y la relación RANKL/OPG y aumentó los depósitos de calcio y colágeno. Los mecanismos por los cuales el Valsartán reduce los efectos inflamatorios producidos por el LPS no están claras, pero la interferencia del ensamblaje de la NAD(P)H oxidasa con apocinina y el Tempol, indica que el Valsartán puede interferir con los pasos para el reconocimiento de LPS y su asociación con TLR4. Concluyéndose que las ERO participan en la señalización intracelular de la ANG II, vía el AT1R. Este estudio ayuda a dilucidar el papel del SRA en procesos inflamatorios. Además contribuye con sus resultados a ofrecer una alternativa terapéutica en el tratamiento de la EP.

Adiponectin and interleukin-6 levels in insulin-treated diabetic rats with experimental periodontitis

The aim of the study was to compare the serum levels of adiponectin and interleukin-6 (IL-6) in insulin-treated diabetic rats with or without periodontitis. Forty male Wistar rats were randomly divided into 2 groups (20 rats each): a) insulin-treated diabetic group (control, DI) and b) insulin-treated diabetic periodontitis group (test, DIP). Diabetes was induced, and insulin treatment was initiated on day 5. On day 16, periodontitis was induced in the DIP group. All rats were euthanized on day 77. Adiponectin and IL-6 were assessed on days 16 and 77. At the end of the experiment, 14 and 11 rats survived in the DI and DIP groups, respectively. Adiponectin levels were statistically significantly higher at the end of the experiment compared with levels on day 16 in the periodontitis group (p < 0.05), but not in the control group. At the end of the experiment, adiponectin levels were statistically significantly higher in the periodontitis group compared with the control group (p < 0.05). Within-group and between-group comparisons of IL-6 levels showed no statistically significant difference. In conclusion, serum adiponectin was increased in insulin-treated diabetic rats with periodontitis in comparison with insulin-treated diabetic rats, while IL-6 levels did not differ between groups.

Experimental periodontal disease treatment by subgingival irrigation with tetracycline hydrochloride 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.

Evaluation of two morphometric methods of bone loss percentages caused by periodontitis in rats in different locations

ABSTRACT OBJECTIVE: The present study evaluated morphometrically bone loss percentages in experimental periodontitis in rats, comparing different locations (lingual mandible, palatal maxilla and buccal maxilla) and two evaluation methods (distance and area methods). MATERIAL AND METHODS: Ligatures were placed around the maxillary right second molar and around the mandibular right first molar in 14 female Wistar rats. The contralateral molars served as intragroup controls. After 4 weeks, the rats were sacrificed and their mandible and maxilla were removed. The specimens were dissected and stained with methylene blue dye. Bone loss was evaluated by two different methods on the surfaces of the defleshed jaw. In the first method, the distance from the cementoenamel junction (CEJ) to the alveolar bone crest was measured in the roots of teeth associated with ligature. In the second method, the area of bone loss was determined using the alveolar tissue bone, CEJ and the proximal region of roots associated with the ligature as reference. The data were converted to bone loss percentages caused by ligature: (ligated - unligated) x 100/ligated. RESULTS: When comparing the distance and area methods, no statistically significant difference was observed (p>0.05). Both methodologies indicated that the maxilla presented greater bone loss than the mandible and it was more accentuated on the buccal side than on the palatal side (p<0.05). CONCLUSIONS: The findings of this study show that both the area and the distance methods can be used to evaluate bone loss caused by ligature placement in rats, and suggest applying the morphometric methodology to the maxilla on the buccal side.

Periodontal disease induced by porphyromonas gingivalis and fusobacterium nucleatum in Wistarrats / Periodontite induzida pela porphyromonas gingivalis e fusobacterium nucleatum em ratos Wistar

Prior studies have shown that it is necessary to place ligatures around molars to study periodontal destruction in rats. The present research aims to examine a periodontal disease model in which specific pathogen-free Wistar rats are orally exposed to Porphyromonas gingivalis associated with Fusobacterium nucleatum. Periodontitis was induced by specific infection with P. gingivalis and F. nucleatum. Twenty adult male Wistar rats were divided into two groups. The control animals were not infected. The experimental animals were repeatedly infected with Porphyromonas gingivalis and Fusobacterium nucleatum for one week. For the next three weeks, the animals were repeatedly infected with P. gingivalis alone. The distance from the cemento-enamel junction (CEJ) to the alveolar bone crest of the second molar was measured at different sites: buccal-distal (d), buccal-furcation region (f), buccal-mesial (h), and area region. The Mann-Whitney test was applied (p<0.001). The results showed that all values obtained were significantly greater in the infected group. Infected group values for the measures d, f, h, and area were 0.41 mm, 0.46 mm, 0.67mm, and 1.04 mm2, respectively, while in the control group, values for the measures d, f, h, and area were0.19 mm, 0.26 mm, 0.26 mm, 0.88 mm2, respectively. Our study showed that four weeks following infection with Porphyromonas gingivalis and Fusobacterium nucleatum bone loss in Wistar rats could be identified.

Expressão e distribuição de CGRP, VEGF e TGF-β na gengiva dos dentes de ratos com periodontite induzida por ligadura: aspectos imunohistoquímicos / Expression and distribution of CGRP, VEGF and TGFß in the gingiva of rats’ teeth with periodontits by ligature induction: immunohistochemical aspects

No momento em que há a agressão tecidual e a defesa inata é deflagrada, mediadores químicos são liberados no local afetado. Esses mediadores podem ser de origem celular tais como CGRP, VEGF e TGFß. Os objetivos desta pesquisa foram avaliar a expressão e distribuição de CGRP, TGFß e VEGF na gengiva do primeiro molar inferior esquerdo de rato no 7° e 14° dias após a indução por ligadura; a expressão e distribuição de CGRP, TGFß e VEGF na gengiva do dente contralateral correspondente sem ligadura, no 7° e 14° dias, e se a indução da periodontite por ligadura no dente experimental provoca uma inflamação na gengiva do dente contralateral correspondente no 7° e 14° dias após a ligadura. Para o desenvolvimento deste trabalho foram selecionados 15 ratos Rattus Novergicus, Albinus, Wistar. O grupo experimental de 12 ratos foi dividido em 2 subgrupos compostos por 6 ratos cada um deles distribuídos da seguinte maneira: os do subgrupo A1 permaneceram com a ligadura no primeiro molar inferior esquerdo por 7 dias e foram sacrificados; os do subgrupo A-2 -permaneceram com a ligadura no primeiro molar inferior esquerdo por 14 dias e foram sacrificados. Outros três animais constituíram o grupo controle. Após o sacrifício dos 12 animais dos grupos experimentais e controle suas mandíbulas foram colocadas em ácido etilenodiaminotetracético (EDTA) neutro para sofrerem descalcificação. Então foram processadas para inclusão em parafina e os cortes histológicos foram corados pela hematoxilina-eosina e submetidos à técnica imunohistoquímica para imunomarcação de CGRP, VEGF e TGFß. Aos 7 dias de ligadura observou-se na lâmina própria gengival, epitélio juncional e epitélio oral, expressiva marcação para CGRP. A expressão de VEGF foi intensa na lamina própria e com pouca ou nenhuma marcação no epitélio oral e juncional. O TGFß apresentou pouca marcação na lâmina própria ou nenhuma marcação no epitélio oral e juncional...

At the time of the tissue aggression the innate defense is triggered and the chemical mediators are released in the affected site. These mediators may have cell origin as the CGRP, VEGF and TGFß. The aim of this research were to evaluate the expression and distribution of the CGRP, VEGF and TGFß in the gingiva of the lower left first molar of rats in the seven and fourteen days after the ligature for inflammation induction; to analyse the expression and distribution of the CGRP, VEGF and TGFß in the gingiva of the correspondent counter lateral tooth without ligature in the seven and fourteen days and if the induction of periodontitis causes gingival inflammation of the counter lateral tooth after seven and fourteen days after ligature. For the development of this work were selected fifteen Rattus Novergicus, Albinus,Wistar. The experimental group of 12 rats was divided into 2 groups consisting of 6 rats each distributed of the following manner: the subgroup A1 remained with ligature in the first molar and left for 7 days before the sacrificed and the subgroup A-2 remained with the ligature for 14 days before the sacrificed. Another 3 animals constituted the control group. After the sacrificed of the 12 experimental and 3 control animals were immersedin neutral ethylenidiaminetetracetic (EDTA) for the decalcification. Then were processed for paraffin embedding. The sections were stained with hematoxylin-eosin and submitted to immunohistochemical techniques to imunostaining for CGRP, VEGF and TGFß. At 7 days of ligature was observed in the gingival lamina propria, junctional epithelium and oral epithelium, strong staining for CGRP. The intensive expression of VEGF occur in the lamina propria and scarce or no staining in the oral and junctional epithelium. The TGFß shows scarce staining in the lamina propria and no staining in the oral and junctional epithelium...

Expressão e distribuição de CGRP, VEGF e TGF-β na gengiva dos dentes de ratos com periodontite induzida por ligadura: aspectos imunohistoquímicos / Expression and distribution of CGRP, VEGF and TGFß in the gingiva of rats’ teeth with periodontits by ligature induction: immunohistochemical aspects

No momento em que há a agressão tecidual e a defesa inata é deflagrada, mediadores químicos são liberados no local afetado. Esses mediadores podem ser de origem celular tais como CGRP, VEGF e TGFß. Os objetivos desta pesquisa foram avaliar a expressão e distribuição de CGRP, TGFß e VEGF na gengiva do primeiro molar inferior esquerdo de rato no 7° e 14° dias após a indução por ligadura; a expressão e distribuição de CGRP, TGFß e VEGF na gengiva do dente contralateral correspondente sem ligadura, no 7° e 14° dias, e se a indução da periodontite por ligadura no dente experimental provoca uma inflamação na gengiva do dente contralateral correspondente no 7° e 14° dias após a ligadura. Para o desenvolvimento deste trabalho foram selecionados 15 ratos Rattus Novergicus, Albinus, Wistar. O grupo experimental de 12 ratos foi dividido em 2 subgrupos compostos por 6 ratos cada um deles distribuídos da seguinte maneira: os do subgrupo A1 permaneceram com a ligadura no primeiro molar inferior esquerdo por 7 dias e foram sacrificados; os do subgrupo A-2 -permaneceram com a ligadura no primeiro molar inferior esquerdo por 14 dias e foram sacrificados. Outros três animais constituíram o grupo controle. Após o sacrifício dos 12 animais dos grupos experimentais e controle suas mandíbulas foram colocadas em ácido etilenodiaminotetracético (EDTA) neutro para sofrerem descalcificação. Então foram processadas para inclusão em parafina e os cortes histológicos foram corados pela hematoxilina-eosina e submetidos à técnica imunohistoquímica para imunomarcação de CGRP, VEGF e TGFß. Aos 7 dias de ligadura observou-se na lâmina própria gengival, epitélio juncional e epitélio oral, expressiva marcação para CGRP. A expressão de VEGF foi intensa na lamina própria e com pouca ou nenhuma marcação no epitélio oral e juncional. O TGFß apresentou pouca marcação na lâmina própria ou nenhuma marcação no epitélio oral e juncional...

At the time of the tissue aggression the innate defense is triggered and the chemical mediators are released in the affected site. These mediators may have cell origin as the CGRP, VEGF and TGFß. The aim of this research were to evaluate the expression and distribution of the CGRP, VEGF and TGFß in the gingiva of the lower left first molar of rats in the seven and fourteen days after the ligature for inflammation induction; to analyse the expression and distribution of the CGRP, VEGF and TGFß in the gingiva of the correspondent counter lateral tooth without ligature in the seven and fourteen days and if the induction of periodontitis causes gingival inflammation of the counter lateral tooth after seven and fourteen days after ligature. For the development of this work were selected fifteen Rattus Novergicus, Albinus,Wistar. The experimental group of 12 rats was divided into 2 groups consisting of 6 rats each distributed of the following manner: the subgroup A1 remained with ligature in the first molar and left for 7 days before the sacrificed and the subgroup A-2 remained with the ligature for 14 days before the sacrificed. Another 3 animals constituted the control group. After the sacrificed of the 12 experimental and 3 control animals were immersedin neutral ethylenidiaminetetracetic (EDTA) for the decalcification. Then were processed for paraffin embedding. The sections were stained with hematoxylin-eosin and submitted to immunohistochemical techniques to imunostaining for CGRP, VEGF and TGFß. At 7 days of ligature was observed in the gingival lamina propria, junctional epithelium and oral epithelium, strong staining for CGRP. The intensive expression of VEGF occur in the lamina propria and scarce or no staining in the oral and junctional epithelium. The TGFß shows scarce staining in the lamina propria and no staining in the oral and junctional epithelium...

Efeito da ingestão crônica de álcool na progressão de periodontite induzida em ratos da linhagem Fischer-344 / Effect of chronic alcohol ingestion on the progression of periodontitis induced in Fisher-344 rats

Objetivo: Compreender o efeito do uso crônico de álcool na progressão de periodontite induzida em ratos da linhagem Fischer-344. Métodos: Para o estudo utilizaram-se 22 ratos da linhagem Fischer-344, com dois meses de idade, divididos nos grupos: álcool (n=8), ligadura (n=7) e controle (n=7). No primeiro dia, expuseram-se os animais do grupo álcool à ingestão de solução de água com álcool a 20% (volume/volume), até o dia 90. Decorridos trinta dias do início do experimento, os animais do grupo álcool e do grupo ligadura submeteram-se à colocação de fio de seda em volta do segundo molar superior direito. Nada foi realizado no lado esquerdo, servindo como controle. Todos os grupos submeteram-se à eutanásia, após 60 dias da colocação da ligadura. Para avaliar a destruição da periodontite, usou-se o exame radiográfico, mensurando a destruição da altura óssea. Resultados: Os resultados do estudo evidenciaram que, no lado em que foi induzida a periodontite, o grupo que ingeriu álcool sofreu um aumento de destruição, demonstrando diferenças estatísticas (p < 0,05), se comparado ao grupo ligadura e ao controle. E, maior destruição óssea no grupo ligadura quando comparado ao controle (p < 0,05). Conclusão: Conclui-se, dentro das limitações do estudo, que o consumo crônico de álcool por ratos da linhagem Fischer-344 induziu a uma maior progressão de periodontite induzida.

Objective: Understand the effect of chronic alcohol on the progression of periodontitis induced in Fischer-344 rats. Methods: For the study, 22 Fischer-344 rats, two months old were used, divided into groups: alcohol (n=8), ligature (n=7) and control (n=7). On the first day, the animals in the alcohol group were exposed to ingestion of a water solution containing 20% alcohol (size/size), up to day 90. After thirty days from the beginning of the experiment, the animals in the alcohol group and the ligature group were submitted to the placement of a silk thread around the right maxillary second molar. Nothing was performed on the left side, serving as control. All the groups were submitted to euthanasia 60 days after ligature placement. To assess the destruction of periodontitis, a radiographic exam was used to measure the destruction of bone height. Results: The results of the study showed that on the side in which periodontitis was induced, the group that ingested alcohol suffered an increase in destruction, with statistical differences when compared with the ligature and control groups and increased bone destruction in the ligature group when compared to control. Conclusion: Within the limitations of the study, it was concluded that chronic alcohol consumption by Fischer-344 rats led to greater progression of induced periodontitis.

Metronidazole-containing gel for the treatment of periodontitis: an in vivo evaluation

The aim of this investigation was to monitor metronidazole concentrations in the gingival crevicular fluid (GCF) collected from periodontal pockets of dogs after treatment with an experimental 15 percent metronidazole gel. Five dogs had periodontitis induced by cotton ligatures placed subgingivally and maintained for a 30-day period. After the induction period, only pockets with 4 mm or deeper received the gel. Each pocket was filled up to the gingival margin by means of a syringe with a blunt-end needle. GCF was collected in paper strips and quantified in an electronic device before and after 15 minutes, 1 h, 6 h, 24 h and 48 h of gel administration. The GCF samples were assayed for metronidazole content by means of a high performance liquid chromatography method. Concentrations of metronidazole in the GCF of the 5 dogs (mean ± SD, in µg/mL) were 0 ± 0 before gel application and 47,185.75 ± 24,874.35 after 15 minutes, 26,457.34 ± 25,516.91 after 1 h, 24.18 ± 23.11 after 6 h, 3.78 ± 3.45 after 24 h and 3.34 ± 5.54 after 48 h. A single administration of the 15 percent metronidazole gel released the drug in the GCF of dogs in levels several-fold higher than the minimum inhibitory concentration for some periodontopathogens grown in subgingival biofilms for up to one hour, but metronidazole could be detected in the GCF at least 48 hours after the gel application.

Comparison of histometric and morphometric analyses of bone height in ligature-induced periodontitis in rats

The purpose of this study was to compare histologic and morphometric procedures of bone height measurement. Microscopic measurements are the most frequent methods in periodontal studies with animals, but have limited capacity to identify bone levels associated with both healthy tissues and periodontal disease. Ligatures were placed in the maxillary left second molars of 10 male 60-day-old Wistar rats for 30 days. Left and right maxillary sides of 5 rats were processed for histologic analysis (H), sectioned buccolingually, and stained with HE. The maxillae of the other 5 rats were defleshed and used for morphometric analysis (M). Histometric measurements from the cementoenamel junction to the bone crest were performed. Standardized photographs were used for morphometric analysis. The t test was used for dependent or independent samples (alpha = 0.05 percent). Distances from cementoenamel junction to bone crest were 0.95 ± 0.25 and 1.07 ± 0.30 mm for H and M, respectively. Buccal measurements were 0.92 ± 0.16 and 1.08 ± 0.35 mm for H and M. The values obtained using H and M for areas without ligatures were 0.44 ± 0.15 and 0.47 ± 0.11 mm for lingual measurements and 0.23 ± 0.08 and 0.41 ± 0.10 mm for buccal measurements. No significant differences were found between the two methods in the detection of bone height associated with the placement of ligatures in rats.

O objetivo deste estudo foi comparar procedimentos de medida da altura óssea histológica e morfométrica. O método mais freqüente de mensuração da altura óssea em estudos em animais são as medidas microscópicas. No entanto, tem limitada capacidade de identificar os níveis ósseos associados com os tecidos saudáveis e doença periodontal. Foram colocadas ligaduras no segundo molar superior esquerdo de 10 ratos machos Wistar com 60 dias de vida durante um período de 30 dias. Hemimaxilas direitas e esquerdas de 5 ratos foram processadas para a análise histológica (H), cortadas no sentido vestíbulo-lingual e coradas com HE. Hemimaxilas dos outros 5 ratos tiveram toda a matéria orgânica removida para análise morfométrica (M). Medidas histométricas da junção cemento-esmalte (JCE) à crista óssea alveolar foram realizadas. Fotografias padronizadas foram utilizadas na análise morfométrica. O teste t foi utilizado para amostras dependentes e independentes (alfa = 0,05 por cento). As distâncias entre a JCE e a crista óssea na face palatina foram de 0,95 ± 0,25 e 1,07 ± 0,30 mm para H e M, respectivamente. As medidas vestibulares foram 0,92 ± 0,16 e 1,08 ± 0,35 mm para H e M. Os valores obtidos usando H e M para áreas sem ligadura foram 0,44 ± 0,15 e 0,47 ± 0,11 mm por lingual e 0,23 ± 0,08 e 0,41 ± 0,10 mm por vestibular, respectivamente. Não houve diferenças estatisticamente significativas entre os dois métodos na detecção da altura óssea associada à colocação de ligaduras em ratos.

Dois métodos histometricos distintos comparativos de periodontite induzida em ratos / Comparison of two distinct histometric methods for the analysis of induced periodontitis in rats

Em instituições que não dispõem de câmara acoplada ao microscópio, buscam-se alternativas para análises histométricas. Com esse objetivo, compararam-se os resultados de dois métodos histométricos distintos em periodontite de ratos. Após anestesia, posicionou-se um fio de seda em volta do segundo molar superior direito, e aguardaram-se 60 dias para a eutanásia. As peças foram preparadas, coradas e montadas.A análise histométrica utilizada foi a distância entre a junção amelocementária na face mesial do segundo molar até a fibra periodontal inserida (Jac-F) e a crista óssea alveolar (Jac-O). Empregaram-se dois métodos de histometria, imagem digitalizada e retroprojetor de lâminas. A partir da obtenção dos dados, foram realizadas as médias dos grupos e comparadas. Os dados foram submetidos à análise estatística, utilizando o teste T para amostras independentes (p<0,05). Os resultados das médias para Jac-F foram 0,97 mm para imagem digitalizada e l, 13 mm para imagem do retroprojetor; já para Jac-O, foram 3,1 mm para imagem digitalizada e 2,8 mm para imagem do retroprojetor.Não se observaram diferenças significativas (p>0,05) entre os grupos, tanto para Jac-F como Jac-O. Conclui-se que as duas metodologias de avaliação histométrica podem fornecer similaridades nos resultados.

Dental caries and periodontitis associated with betel quid chewing: analysis of two data sets.

BACKGROUND: Not much research evidence concerning the relationship between betel quid chewing and oral health has been established although betel quid chewing is a common practice among people in many Asian countries including rural areas of Thailand. OBJECTIVE: The present study employed two existing data sets to evaluate the association between betel quid chewing and oral diseases. MATERIAL AND METHOD: The study populations for phase I comprised a total of 796 females, aged 30-89 years, residing in five districts of Khon Kaen province, Thailand during 1990-91. In phase II, there were 2,253 females, aged 31-86 years, residing in Chonnabot district, Khon Kaen province, Thailand during 1992-94, respectively. The data were obtained through oral examination and interview. The analyses employed descriptive, bivariate, and multivariable logistic regression. RESULTS: Findings from final multivariable logistic regression models revealed the inverse relationship between betel quid chewing and dental caries adjusting for other variables. In addition, results from the final multivariable logistic regression models predicting periodontitis showed that betel quid chewing was directly associated with periodontitis in the presence of several confounding factors. The consistent findings from both data sets suggest that although betel quid chewing may reduce dental caries, it was directly related to periodontitis and enhanced the possibility of increasing tooth loss. CONCLUSION: Therefore, preventive programs aiming at discouraging Thai people from chewing betel quid should be established to preserve favorable oral health.

Caracterización de un modelo de regeneración de los tejidos periodontales luego de una periodontitis inducida experimentalmente en ratas. Estudio histomorfométrico

Introducción - La regeneración de los tejidos periodontales luego de una periodontitis experimental inducida por una ligadura cervical, colocada en molares inferiores de rata durante cinco días, fue analizada por métodos histomorfométricos aIos cero, cinco, siete y diez días del retiro de Ia ligadura cervical. Métodos - En cortes orientados y coloreados con hematoxilina y eosina, los siguientes parámetros morfométricos fueron evaluados según los principios de Ia estereología: volumen óseo total en el espacio interradicular (VOT) y volumen de los tejidos blandos remanentes (VTBR). Resultados - Cinco días luego del retiro de Ia ligadura cervical, ambos parámetros disrninuyen. AIos siete días ambos parámetros incrementaron su valor, siendo mucho mas marcado el aumento de VTBR, el cual registró el 92 por ciento de su valor normal aIos diez días de retirada Ia ligadura cervical. Conclusión -La caracterización de este modelo experimental provee Ia base para estudios comparativos bajo diferentes condiciones experimentales.

Estudo comparativo da utilização local de tetraciclina, minociclina e ácido cítrico como adjuntos a instrumentação periodontal: análise histológica e histomorfométrica em ratos / Comparative study of tetracycline, minocycline or citric acid local use associated to periodontal instrumentation: a histological and histomorphometrical analysis in rats

O reparo tecidual após terapia periodontal envolve a formação de tecido epitelial e conjuntivo a partir da biocompatibilização da superfície radicular. O objetivo deste estudo foi investigar se a utilização de soluções condicionantes como tetraciclina (TTC-HCI), minociclina ou ácido cítrico associados à instrumentação periodontal pode melhorar a reparação após a terapia periodontal. Este estudo utilizou 80 animais que receberam uma ligadura de algodão em tomo do 2~SE. Após cinco semanas a ligadura foi removida e os dentes foram tratados com raspagem e irrigação com uma das seguintes soluções: TTC-HCl 10% (16 animais) , minociclina 10% (16 animais), ácido cítrico 8% (16 animais),NaCI 0,9% ( 16 animais) ou, apenas com raspagem (16 animais). Para delimitar a área utilizada na análise histológica foi realizada uma marca na superfície radicular. Os animais foram sacrificados aos 32, 72, 212 e 602 dias após tratamento. Os espécimes foram processados para análise histomorfométrica para determinar a porcentagem de preenchimento da marca. Os dados foram analisados por ANOV A a dois critérios e pelo Teste Tukey, com nível de significância 5%. Os resultado da análise histomorfométrica demonstraram que o tempo de sacrifício influenciou o reparo tecidual independentemente da medicação utilizada, mostrando resultados melhores nos animais sacrificados 60 dias após o tratamento. As soluções condicionantes ácidas apresentaram resultados equivalentes entre si e ao NaCI, e melhores apenas que os animais tratados com raspagem. Estes resultados indicaram que a utilização de tetraciclina, minociclina ou ácido cítrico, associado à instrumentação periodontal, comparada à utilização de NaCl, não melhorou o reparo tecidual no tratamento da periodontite induzida em ratos.

Depresión mayor y salud oral: rol de los fármacos antidepresivos / Major depression and oral health: role of antidepressant agents

La mayoría de los fármacos antidepresivos, así como otras drogas usadas en el manejo de los cuadros depresivos son hiposalivantes. La disminución del flujo salival produce alteraciones en los tejidos blandos y duros de la cavidad oral. Las principales patologías que se han descritos asociadas a hiposialia son las caries dentarias, la candidiasis oral y en algún grado la gingivitis y periodontitis. Adicionalmente, estas patologías pueden verse exacerbadas por el abandono de los hábitos de higiene oral, debido a las alteraciones del ánimo de los pacientes. Algunas de estas infecciones bucales pueden en ocaciones comprometer gravemente la salud general. Dado el mayor riesgo de los pacientes con hiposialia de desarrollar patologías orales, y sus eventuales consecuencias en la salud general, como a nivel del estado sicológico de los pacientes, es que resulta importante reducir en lo posible la incidencia de estas patologías orales en pacientes depresivos, principalmente aquéllos en tratamiento con psicofármacos hiposalivantes