Sports mouthguards: Contamination, roughness, and chlorhexidine for disinfection - A randomized clinical trial

Abstract The aim of the present in vivo study was to evaluate the bacterial contamination of sports mouthguards, surface roughness, and the efficacy of chlorhexidine gluconate spray in the disinfection of these devices. A randomized, blinded cross-over clinical trial was performed with twenty 9 to 13 years old children who practiced martial arts and participated in all phases of the study. They were instructed to wear mouthguards 3 alternated days a week for 1 hour and, after use, to spray sterile tap water or chlorhexidine 0.12%. The mouthguards were analyzed by MTT assay, Checkerboard DNA-DNA hybridization, and confocal laser microscopy prior and after use for 2 weeks. Data were analyzed by Wilcoxon and t-Student, and Pearson correlation tests, with 5% significance level. Were observed that mouthguards of the control group were more contaminated with cariogenic microorganisms than those of the chlorhexidine group (p<0.05). The mouthguards use of spray of chlorhexidine reduced significantly the bacteria contamination compared with control group (p = 0.007). The surface roughness of the mouthguards increased significantly after use, irrespective of application of chlorhexidine spray. A moderate correlation (r=0.59) was observed between surface roughness and the cariogenic microorganism's contamination only for control group. Sports mouthguards had intense microbial contamination and increased surface roughness after its use. The use of chlorhexidine spray was effective for reducing the mouthguards contamination used by children.

Resumo O objetivo do presente estudo in vivo foi avaliar a contaminação bacteriana de protetores bucais esportivos, a rugosidade da superfície e a eficácia do spray de gluconato de clorexidina na desinfecção desses dispositivos. Um ensaio clínico randomizado, cego, cruzado foi realizado com vinte crianças de 9 a 13 anos, que praticavam artes marciais, participaram de todas as fases do estudo. As crianças foram orientadas a usar o protetor bucal por 3 dias alternados durante 1 hora e, após o uso, borrifar água de torneira estéril ou clorexidina 0,12%. Os protetores foram analisados por ensaio MTT, Hibridização DNA-DNA e microscopia confocal a laser antes e após o uso por 2 semanas. Os dados foram analisados pelos teste de Wilcoxon, teste t de Student, e correlação de Pearson, com nível de significância de 5%. Observou-se que os protetores bucais do grupo controle estavam mais contaminados com microrganismos cariogênicos do que os do grupo experimental (clorexidina) (p <0,05). O uso de protetores bucais com spray de clorexidina reduziu significativamente a contaminação bacteriana em relação ao grupo controle (p = 0,007). A rugosidade da superfície dos protetores bucais aumentou significativamente após o uso, independentemente da aplicação de spray de clorexidina. Uma correlação moderada (r = 0,59) foi observada entre a rugosidade da superfície e a contaminação do micro-organismo apenas para o grupo controle. Os protetores bucais esportivos apresentam intensa contaminação microbiana e aumento da rugosidade superficial após o uso. O uso de spray de clorexidina foi eficaz para reduzir a contaminação dos protetores bucais usados por crianças.

Randomized clinical trials in periodontology: focus on outcomes selection

Abstract Randomized clinical trials (RCTs) are human studies carried out to compare different treatments or interventions, and their results are used to support clinical decision-making and improve patient care. Herein, the aim of this study was to review the selection process of study outcomes in periodontology. Primary outcomes should draw the main conclusions of the study, whereas secondary outcomes should only be used to help explain the main findings and generate future research hypothesis. Outcomes are classified as clinically relevant (CROs) or surrogate outcomes. CROs - the first option for primary outcome variables - should convey not only substantial health benefits, but also be deemed important by patients. In periodontology, tooth loss/retention and oral health-related quality of life (OHRQoL) are examples of CROs. While tooth loss has main limitations as a primary outcome, emerging evidence suggest that patient-reported outcome measures (PROMs) can accurately detect OHRQoL following periodontal therapy. When CROs cannot be assessed, validated surrogate outcomes can be used as proxies. Primary outcome variables should reflect a treatment endpoint at the patient level that can be easily used to inform decision-making in daily practice. These outcomes should allow the implementation of a treat-to-target concept in which the intervention can be clearly judged against a prespecified treatment target. Recently, the presence of at most 4 sites with periodontal probing depth ≥5 mm post-treatment was suggested as an effective endpoint for periodontal trials. In perspective, a combination of validated clinical parameters and PROMs will provide a more comprehensive assessment of periodontal treatments.

In vitro antimicrobial effect of cetylpyridinium chloride on complex multispecies subgingival biofilm

Abstract Periodontopathogenic subgingival biofilm is the main etiological agent of periodontitis. Thus, a search for antimicrobials as adjuvant for periodontal treatment in the literature is intense. Cetylpyridinium chloride (CPC) is a well-known antimicrobial agent commonly used in mouthrinses. However, CPC effects on a complex biofilm model were not found over the literature. Therefore, the aim of this manuscript is to evaluate 0.075% CPC antimicrobial properties in a multispecies subgingival biofilm model in vitro. The subgingival biofilm composed by 31 species related to periodontitis was formed for 7 days, using the calgary device. The treatments with CPC and chlorhexidine (CHX) 0.12% (as positive control) were performed 2x/day, for 1 min, from day 3 until the end of experimental period, totaling 8 treatments. After 7 days of biofilm formation, biofilm metabolic activity was evaluated by a colorimetric reaction and biofilms microbial composition by DNA-DNA hybridization. Statistical analysis was performed using ANOVA with data transformed via BOX-COX followed by Dunnett post-hoc. Both CPC and CHX reduced biofilm metabolic activity in 60% and presented antimicrobial activity against 13 different species. Specifically, only CHX reduced levels of F.n. vicentii and P. gingivalis while only CPC reduced A. odontolyticus and A. israelli. CPC was as effective as CHX as antimicrobial through in vitro complex multispecies subgingival biofilm. However, future studies using in vivo models of experimental periodontal disease should be performed to prove such effect.

Resumo O biofilme subgengival periodontopatogênico é o principal agente etiológico da periodontite. Assim, a pesquisa de antimicrobianos como adjuvantes para o tratamento periodontal na literatura é intensa. Cloreto de cetilpiridínio (CPC) é um agente antimicrobiano comumente usado em enxaguatórios bucais. No entanto não foram encontrados na literatura estudos avaliando os efeitos do CPC em um modelo complexo de biofilme. Portanto, o objetivo deste artigo é avaliar as propriedades antimicrobianas do cloreto de cetilpiridinio 0,075% em um modelo de biofilme subgengival multiespécie in vitro. O biofilme subgengival composto por 31 espécies relacionadas à periodontite foi formado por 7 dias, utilizando o dispositivo calgary. Os tratamentos com CPC e clorexidina (CHX) 0,12% (controle positivo) foram realizados 2x/dia, por 1 min, do dia 3 até o final do período experimental, totalizando 8 tratamentos. Após 7 dias de formação do biofilme, a atividade metabólica do biofilme foi avaliada por reação colorimétrica e a composição microbiana dos biofilmes por hibridização DNA-DNA. A análise estatística foi realizada usando ANOVA com dados transformados via BOX-COX seguido do teste de Dunnett. Tanto o CPC como a CHX reduziram a atividade metabólica do biofilme em aproximadamente 60% e apresentaram atividade antimicrobiana contra 13 espécies diferentes. Especificamente, apenas os níveis de F.n. Vicentii e P. gingivalis foram reduzidos somente pelo tratamento com a CHX enquanto apenas o CPC reduziu A. odontolyticus e A. israelli. O CPC foi tão eficaz quanto o CHX como antimicrobiano através de biofilme subgengival complexo multiespecífico in vitro. No entanto, futuros estudos usando modelos in vivo de doença periodontal experimental devem ser realizados para comprovar tal efeito.

Microbial profile of symptomatic pericoronitis lesions: a cross-sectional study

Abstract Objective: The microbial composition of pericoronitis (Pc) is still controversial; it is not yet clear if the microbial profile of these lesions is similar to the profile observed in periodontitis (Pd). Therefore, the aim of the present study was to describe the microbial profile of Pc lesions and compare it directly with that of subjects with Pd. Methodology: Subjects with Pc and Pd were selected, and subgingival biofilm samples were collected from (i) third molars with symptomatic Pc (Pc-T), (ii) contralateral third molars without Pc (Pc-C) and (iii) teeth with a probing depth >3 mm from subjects with Pd. Counts and proportions of 40 bacterial species were evaluated using a checkerboard DNA-DNA hybridization technique. Results: Twenty-six patients with Pc and 18 with Pd were included in the study. In general, higher levels of microorganisms were observed in Pd. Only Actinomyces oris and Eubacterium nodatum were present in higher mean counts in the Pc-T group in comparison with the Pc-C and Pd-C groups (p<0.05). The microbiota associated with Pc-T was similar to that found in Pc-C. Sites with Pc lesions had lower proportions of red complex in comparison with the Pd sites. Conclusion: The microbiota of Pc is very diverse, but these lesions harbour lower levels of periodontal pathogens than Pd.

Microbiological and clinical effects of adjunctive systemic metronidazole and amoxicillin in the non-surgical treatment of peri-implantitis: 1 year follow-up

Abstract The aim of this study was to evaluate the effects of adjunct systemic antibiotic treatment with metronidazole (MTZ) and amoxicillin (AMX) in patients receiving non-surgical subgingival debridement (NSD) for peri-implantitis. Forty subjects presenting with at least one implant with severe peri-implantitis were randomized into an experimental group [treated with NSD plus MTZ (400 mg) and AMX (500 mg) three times a day for 14 days] and a control group treated with NSD plus placebo. Clinical parameters and submucosal biofilm profiles were evaluated up to 1 year post-treatment. Overall, both treatments improved clinical parameters over time. At 1 year, mean probing depth (PD), mean clinical attachment (CA) level and proportions of red complex pathogens did not differ significantly between the two groups. In addition, mean PD and CA changes to 1-year posttreatment did not differ significantly between the two groups between baseline and 1-year post-treatment. These results suggest that the addition of MTZ and AMX to the treatment protocol of patients undergoing NSD for with severe peri-implantitis does not improve the clinical and microbiological outcomes of NSD. The fact that half of the implants in both groups did not achieve clinical success (PD < 5 mm, no BoP, no bone loss) suggest that neither of the tested protocols were effective for treating severe peri-implantitis.

Additive manufacturing of titanium alloy could modify the pathogenic microbial profile: an in vitro study

Abstract Additive manufacturing (AM) is an emerging process for biomaterials and medical devices. Direct Laser Metal Sintering (DLMS) is an AM technique used to fabricate Ti-6Al-4V implant materials with enhanced surface-related properties compared with wrought samples; thus, this technique could influence microbial adsorption and colonization. Therefore, this in vitro study was conducted to evaluate the impact of different implant production processes on microbial adhesion of periodontal pathogens. Titanium discs produced using two different processes—conventional and AM—were divided into three groups: conventional titanium discs with machined surface (G1), AM titanium discs with chemical treatment (G2) and AM titanium discs without chemical treatment (G3). Subgingival biofilm composed of 32 species was formed on the titanium discs, and positioned vertically in 96-well plates, for 7 days. The proportions of microbial complexes and the microbial profiles were analyzed using a DNA-DNA hybridization technique, and data were evaluated using Kruskal-Wallis and Dunnett tests (p < 0.05). Lower proportions of the red complex species were observed in the biofilm formed in G2 compared with that in G1 (p < 0.05). Moreover, the proportions of the microbial complexes were similar between G2 and G3 (p > 0.05). Compared with G1, G2 showed reduced levels of Porphyromonas gingvalis , Actinomyces gerencseriae, and Streptococcus intermedius , and increased levels of Parvimonas micra , Actinomyces odontolyticus, and Eikenella corrodens (p < 0.05). The microbial profile of G3 did not differ from G1 and G2 (p > 0.05). The results of this in vitro study showed that titanium discs produced via AM could alter the microbial profile of the biofilm formed around them. Further clinical studies should be conducted to confirm these findings.

Does subgingival bacterial colonization differ between implants and teeth? A systematic review

Abstract The aim was of this study was to determine the current weight of evidence for the existence of specific differences between the microbiota of healthy teeth and healthy implants, or of teeth with periodontitis and implants with peri-implantitis. A systematic review was conducted according to the PRISMA statement. The MEDLINE, EMBASE and Cochrane databases were searched up to February 2018 for studies comparing microbiological data of biofilm samples collected from healthy teeth and implants or from teeth with periodontitis and implants with peri-implantitis. The weight of evidence was defined in three categories (strong, moderate and mild/some), according to the difference in number of studies showing statistically significantly higher counts and/or proportions and/or abundance and/or prevalence of microorganisms in health or in disease. Of the 132 articles identified, 8 were included. A wide range of microorganisms were present in different conditions but no microorganisms showed strong, moderate or mild/some evidence for a specific association with either teeth or implants. The results of this systematic review indicated that there is insufficient evidence in the literature to support specific differences between microorganisms colonizing teeth and implants, either in health or in disease.

Subgingival microbial profile of women with breast cancer: a cross-sectional study

Background: Some prospective studies have observed associations between periodontal disease and breast cancer. Therefore, the aim of the present study was to investigate the composition of the subgingival biofilm of women diagnosed with breast cancer, who also presented with chronic periodontitis. Methods: All subjects underwent clinical and microbiological assessment. Subgingival biofilm samples were taken from at least three sites of 44 women who had breast cancer. The mean levels and proportions of 40 bacterial species were determined by checkerboard DNA-DNA hybridization. Spearman correlation was used to assess possible associations between the mean levels of bacterial species and clinical conditions. Results: The five species found at the highest levels were Prevotella nigrescens, Actinomyces gerencseriae, Neisseria mucosa, Porphyromonas gingivalis and Tannerella forsythia. The species detected in the lowest counts were Propionibacterium acnes, Streptococcus constellatus, Streptococcus intermedius, Eubacterium saburreum and Streptococcus anginosus. No significant association between levels and proportion of bacterial species and clinical parameters were found. Conclusion: In conclusion, the results of the present study found no direct association between the subgingival microbiota and breast cancer and an indirect pathway should be addressed in further studies.

Successful and failed mini-implants: microbiological evaluation and quantification of bacterial endotoxin

Abstract Objectives Using two groups of mini-implants (successful and failed) the objectives of this in vivo study were: to evaluate the microbial contamination by the checkerboard DNA-DNA hybridization technique and to quantify the bacterial endotoxin by the limulus amebocyte lysate assay. Material and Methods The 15 successful and 10 failed mini-implants (1.6 mm diameter × 7.0 or 9.0 mm long), placed in the maxilla and/or mandible, were obtained from 15 patients undergoing orthodontic treatment. Data were analyzed statistically by the Wilcoxon rank-sum test using the SAS software (a=0.05). Results All 40 microbial species were detected in both groups of mini-implants, with different frequencies. No differences were observed between the groups with respect to microbial complexes (blue, purple, yellow, green, orange, red and other species) and endotoxin quantification (p>0.05). Conclusion Neither microbial contamination nor endotoxin quantification was determinant for the early loss of stability of the mini-implants.

Evaluation of Enterococcus faecalis, Staphylococcus warneri and Staphylococcus aureus species in adults with generalized chronic periodontitis / Avaliação das espécies Enterococcus faecalis, Staphylococcus warneri e Staphylococcus aureus em adultos com periodontite crônica generalizada

ABSTRACT Objective: To identify and quantify the levels of three bacterial species that have recently been identified as potential "new" periodontal pathogens (Enterococcus faecalis, Staphylococcus aureus and Staphylococcus warneri) in subjects with periodontal health and generalized chronic periodontitis. Methods: Thirty adults with generalized chronic periodontitis and 10 periodontally healthy were included in this study. Nine subgingival biofilm samples were collected per subject and individually analyzed by checkerboard DNA-DNA hybridization technique. Results: The mean levels of E. faecalis and S. warneri were higher in chronic periodontitis than in periodontal health (p<0.05). Furthermore, a higher percentage of subjects with periodontitis were colonized by the three species evaluated in comparison with healthy subjects (p<0.05). This represented a difference of 40 percentage points between the two groups, for E. faecalis (present in 90% of individuals with periodontitis and 50% of the healthy individuals) and S. warneri (100% and 60%, respectively), and 26 percentage points for S. aureus (86% and 60%, respectively). Conclusion: E. faecalis and S. warneri have the potential to be periodontal pathogens. The role of S. aureus was less evident, since this species was more prevalent and at relatively higher levels in health than the other two species. These data might guide future studies on the role of these microorganisms in the etiology of periodontitis and help to establish more effective treatments for these infections.

RESUMO Objetivo: Identificar e quantificar os níveis de três espécies bacterianas que foram recentemente apontadas como possíveis "novos" patógenos periodontais (Enterococcus faecalis, Staphylococcus warneri e Staphylococcus aureus), em indivíduos periodontalmente saudáveis e com periodontite crônica generalizada. Métodos: A amostra foi composta por 30 indivíduos adultos com periodontite crônica generalizada e 10 periodontalmente saudáveis. Nove amostras de biofilme subgengival foram coletadas por indivíduo e analisadas individualmente pela técnica de checkerboard DNA-DNA hybridization. Resultados: Os níveis médios de E. faecalis e S. warneri foram maiores no grupo com periodontite crônica do que no de saúde periodontal (p<0,05). Além disso, um maior percentual de indivíduos com periodontite estavam colonizados pelas três espécies avaliadas em comparação com os indivíduos saudáveis (p<0,05). Essa diferença entre os dois grupos foi de 40 pontos percentuais para E. faecalis (presente em 90% dos indivíduos com periodontite e 50% dos saudáveis) e S. warneri (100% e 60%, respectivamente), e de 26 pontos percentuais para S. aureus (86% e 60%, respectivamente). Conclusão: E. faecalis e S. warneri tem potencial para serem patógenos periodontais. O papel do S. aureus foi menos evidente, uma vez que esta espécie estava mais prevalente e em níveis relativamente mais altos do que as outras duas espécies em saúde. Estes dados podem guiar futuros estudos sobre o papel dessas espécies na etiologia das periodontites e ajudar a estabelecer tratamentos mais eficazes para essas infecções.

Influence of glycemic control on the levels of subgingival periodontal pathogens in patients with generalized chronic periodontitis and type 2 diabetes

Abstract Objective This study evaluated the influence of glycemic control on the levels and frequency of subgingival periodontal pathogens in patients with type 2 diabetes mellitus (DM) and generalized chronic periodontitis (ChP). Material and Methods Fifty-six patients with generalized ChP and type 2 DM were assigned according to the levels of glycated hemoglobin (HbA1c) into one of the following groups: HbA1c<8% (n=28) or HbA1c≥8% (n=28). Three subgingival biofilm samples from sites with probing depth (PD)<5 mm and three samples from sites with PD≥5 mm were analyzed by quantitative Polymerase Chain Reaction (PCR) for the presence and levels of Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Eubacterium nodatum, Parvimona micra, Fusobacterium nucleatum ssp. and Prevotella intermedia. Results The mean counts of F. nucleatum ssp. were statistically significantly higher in the sites with PD≥5 mm of the HbA1c≥8% group (p<0.05). Frequencies of detection of T. forsythia, E. nodatum, P. micra and F. nucleatum ssp. were all higher in the sites with PD≥5 mm of the patients with HbA1c≥8%, compared with those of patients with HbA1c<8% (p<0.05). Frequency of detection of P. intermedia was higher in the sites with PD<5 mm of the patients with HbA1c≥8% than those of the patients with HbA1c<8% (p<0.05). Conclusions Poor glycemic control, as indicated by HbA1c≥8%, is associated with increased levels and frequencies of periodontal pathogens in the subgingival biofilm of subjects with type 2 DM and ChP.

Effectiveness of a pre-procedural mouthwash in reducing bacteria in dental aerosols: randomized clinical trial

Abstract The aim of this randomized, single blinded clinical trial was to evaluate the effect of a pre-procedural mouthwash containing cetylpyridinium chloride (CPC), zinc lactate (Zn) and sodium fluoride (F) in the reduction of viable bacteria in oral aerosol after a dental prophylaxis with ultrasonic scaler. Sixty systemically healthy volunteers receiving dental prophylaxis were randomly assigned to one of the following experimental groups (15 per group): (i) rinsing with 0.075% CPC, 0.28% Zn and 0.05% F (CPC+Zn+F), (ii) water or (iii) 0.12% chlorhexidine digluconate (CHX), and (iv) no rinsing. Viable bacteria were collected from different locations in the dental office on enriched TSA plates and anaerobically incubated for 72 hours. The colonies were counted and species were then identified by Checkerboard DNA–DNA Hybridization. The total number of colony-forming units (CFUs) detected in the aerosols from volunteers who rinsed with CPC+Zn+F or CHX was statistically significantly (p<0.05) lower than of those subjects who did not rinse or who rinsed with water. When all locations were considered together, the aerosols from the CPC+Zn+F and CHX groups showed, respectively, 70% and 77% fewer CFUs than those from the No Rinsing group and 61% and 70% than those from the Water group. The mean proportions of bacterial species from the orange complex were statistically significantly (p<0.05) lower in aerosols from the CPC+Zn+F and CHX groups compared with the others two groups. In conclusion, the mouthwash containing CPC+Zn+F, is effective in reducing viable bacteria in oral aerosol after a dental prophylaxis with ultrasonic scaler.

Association of three putative periodontal pathogens with chronic periodontitis in Brazilian subjects

ABSTRACT Objective The aim of this study was to evaluate the association of Porphyromonas endodontalis, Filifactor alocis and Dialister pneumosintes with the occurrence of periodontitis. Material and Methods Thirty subjects with chronic periodontitis (ChP) and 10 with periodontal health (PH) were included in the study. Nine subgingival biofilm samples were collected as follows: i) PH group - from the mesial/buccal aspect of each tooth in two randomly chosen contralateral quadrants; ii) ChP group - from three sites in each of the following probing depth (PD) categories: shallow (≤3 mm), moderate (4-6 mm) and deep (≥7 mm). Checkerboard DNA-DNA hybridization was used to analyze the samples. Results We found the three species evaluated in a higher percentage of sites and at higher levels in the group with ChP than in the PH group (p<0.05, Mann-Whitney test). We also observed these differences when the samples from sites with PD≤4 mm or ≥5 mm of subjects with ChP were compared with those from subjects with PH (p<0.05, Mann-Whitney test). In addition, the prevalence and levels of D. pneumosintes, and especially of F. alocis were very low in healthy subjects (0.12x105 and 0.01x105, respectively). Conclusion F. alocis and D. pneumosintes might be associated with the etiology of ChP, and their role in the onset and progression of this infection should be further investigated. The role of P. endodontalis was less evident, since this species was found in relatively high levels and prevalence in the PH group.

Comparison of independent and dependent culture methods for the detection of transient bacteremia in diabetic subjects with chronic periodontitis / Comparación entre métodos de cultivo independientes y dependientes para la detección de bacteriemia transitoria en individuos diabéticos con periodontitis crónica

Introduction: Oral-derived bacteremia may occur after several dental procedures and routine daily activities. Some conditions of the oral cavity may favor episodes of bacteremia. This would be the case of patients with diabetes mellitus and periodontitis, who exhibit exacerbated gingival inflammation and may be more prone to developing oral-derived bacteremia. Objective: To compare the effectiveness of an independent culture method (quantitative real-time PCR- qCR) and the most commonly used method (BacT-ALERT 3D ® ) for the diagnosis of bacteremia. Materials and methods: Blood samples were drawn from subjects with type 2 diabetes mellitus and chronic periodontitis before and after apple chewing. Samples were processed by an automated blood culture system (BacT-ALERT 3D ® ) monitored for 15 days with suitable subculture of positive cultures. In parallel, whole DNA from blood samples was purified using a commercial kit and screened by qPCR using a universal primer set of 16S rDNA for bacteria detection. Results: Blood cultures taken before apple chewing were shown to be negative by the two diagnostic methods. After chewing, two samples (11%) showed bacterial growth by BacT-ALERT 3D ® whereas qPCR did not detect the presence of bacteria in any sample. Conclusions: qPCR did not show greater effectiveness than the BacT-ALERT 3D ® in the detection of bacteremia of oral origin.

Introducción. Las bacteriemias de origen oral pueden ocurrir después de procedimientos odontológicos y de otros actos cotidianos. Algunas condiciones de la cavidad oral favorecen las bacteriemias como en el caso de pacientes con diabetes mellitus y periodontitis que presentan inflamación gingival exacerbada. Objetivo. Comparar la eficacia de un método independiente de cultivo (PCR cuantitativa) y otro dependiente (BacT-ALERT 3D ® ) en la detección de la bacteriemia. Materiales y métodos. Se tomaron muestras de sangre de individuos con diabetes mellitus de tipo II y periodontitis, antes y después de la masticación de manzana. Una alícuota se procesó por el sistema automatizado de hemocultivo (BacT-ALERT 3D ® ) y se monitorizó durante 15 días; la otra alícuota fue tratada para la extracción del ADN y procesada por RT-PCR usando un conjunto de cebadores de 16S rDNA exclusivos para bacterias. Resultados. En las muestras tomadas antes de masticar se confirmó la ausencia de bacterias mediante los dos métodos. En las muestras tomadas después de masticar la presencia de bacterias se evidenció únicamente en dos hemocultivos y en ninguna de las muestras se detectó la presencia de bacterias con el método de RT-PCR. Conclusiones. La PCR cuantitativa no mostró mayor eficacia que el BacT-ALERT 3D ® en la detección de la bacteriemia de origen oral.

The effect of systemic antibiotics administered during the active phase of non-surgical periodontal therapy or after the healing phase: a systematic review

Objective The aim of this systematic review was to compare the clinical effectiveness of systemic antibiotics administered in the active stage of periodontal treatment or after the healing phase. Material and Methods An electronic search was performed in the databases EMBASE, MEDLINE and Cochrane Central Register of Controlled Trials (CENTRAL), in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) statement. A manual search of the reference list of selected studies and of review articles was also performed up to November 2013. Randomized Clinical Trials (RCT) that evaluated the systemic administration of antibiotics as adjuvants to scaling and root planning (SRP) at different phases of periodontal treatment were included. Systematic reviews and studies that evaluated subjects with systemic diseases and those that used subantimicrobial doses of antibiotics were excluded. Results The initial search identified 1,039 articles, of which seven were selected, and only one met the inclusion criteria. This study showed that subjects taking metronidazole and amoxicillin at the initial phase of treatment exhibited statistically significantly greater reduction in pocket depth and gain in clinical attachment level in initially deep sites (PD≥7 mm) than subjects taking antibiotics after healing (p<0.05). This comparison was conducted 2 months after antibiotic intake, at the healing phase. Conclusion To date, only one short-term RCT has directly compared different moments of systemic antibiotics administration, as adjuncts to SRP, in the treatment of periodontitis. Although the results of this study suggested some benefits for antibiotics intake during the active phase of therapy, these findings need to be confirmed by larger placebo-controlled randomized clinical trials with longer follow-up periods. .

Microbial Reduction by Two Chemical-Mechanical Protocols in Primary Teeth with Pulp Necrosis and Periradicular Lesion - An In Vivo Study

The objective of this study was to determine the efficacy of chemical-mechanical procedures of two endodontic protocols for septic content reduction of root canals from primary teeth with pulp necrosis and periradicular lesion. Twenty-four primary root canals with pulp necrosis and periradicular lesion were divided into two treatment groups (n=12): multiple-visit and single-visit protocols. Samples were collected using sterile paper points before and after endodontic cleaning followed by microbiological identification through checkerboard DNA-DNA hybridization. Statistical analysis was performed using Proportion Test for score=0 comparing the findings before and after treatment for each group (Wilcoxon's test) as well as the differences in scores between protocols (Mann-Whitney's test) (p<0.05). Data were expressed as prevalence (presence or absence) and estimate of the average count (x105 cells) of each species. Differences in proportions of score=0 prior to treatment were non-significant (p=0.415), demonstrating equivalence between groups. A significant increase in score=0 was detected after treatment for both groups (p<0.0001). Single-visit protocol achieved a significantly greater reduction in mean scoring following endodontic treatment (p=0.024). Both protocols were capable of significantly reducing septic content in root canals of primary teeth with periradicular lesion. Moreover, single-visit protocol showed greater efficacy in reducing endodontic infection.

O objetivo deste estudo foi determinar a eficácia das manobras químico-mecânicas de dois protocolos endodônticos, na redução do conteúdo séptico de canais radiculares de dentes decíduos com polpa necrosada e lesão perirradicular. Vinte e quatro canais radiculares decíduos com necrose pulpar e lesão perirradicular foram divididos em dois grupos de tratamento (n=12): multisessões e sessão única. Amostras foram coletadas usando pontas de papel estéreis, antes e após a limpeza endodôntica, seguido de identificação microbiológica por hibridização DNA-DNA checkerboard. A análise estatística foi realizada usando teste de proporções para escore=0, comparando os achados antes e após tratamento para cada grupo (teste de Wilcoxon) e as diferenças dos escores entre os protocolos (teste de Mann-Whitney) (p<0,05). Os dados foram expressos em prevalência (presença ou ausência) e contagem média (x105 células) de cada espécie. As diferenças nas proporções de escore=0 antes do tratamento não foram significativas (p=0,415), mostrando equivalência entre os grupos. Um aumento significativo de escore=0 foi detectado após o tratamento para ambos os grupos (p<0,0001). O protocolo de sessão única mostrou uma redução significativamente maior dos escores médios após o tratamento endodôntico (p=0,024). Ambos os protocolos são capazes de reduzir significativamente o conteúdo séptico de canais radiculares de dentes decíduos com lesão perirradicular. Entretanto, o protocolo de sessão única mostrou uma maior eficácia na redução da infecção endodôntica.

Mechanisms of action of systemic antibiotics used in periodontal treatment and mechanisms of bacterial resistance to these drugs

Antibiotics are important adjuncts in the treatment of infectious diseases, including periodontitis. The most severe criticisms to the indiscriminate use of these drugs are their side effects and, especially, the development of bacterial resistance. The knowledge of the biological mechanisms involved with the antibiotic usage would help the medical and dental communities to overcome these two problems. Therefore, the aim of this manuscript was to review the mechanisms of action of the antibiotics most commonly used in the periodontal treatment (i.e. penicillin, tetracycline, macrolide and metronidazole) and the main mechanisms of bacterial resistance to these drugs. Antimicrobial resistance can be classified into three groups: intrinsic, mutational and acquired. Penicillin, tetracycline and erythromycin are broad-spectrum drugs, effective against gram-positive and gram-negative microorganisms. Bacterial resistance to penicillin may occur due to diminished permeability of the bacterial cell to the antibiotic; alteration of the penicillin-binding proteins, or production of β-lactamases. However, a very small proportion of the subgingival microbiota is resistant to penicillins. Bacteria become resistant to tetracyclines or macrolides by limiting their access to the cell, by altering the ribosome in order to prevent effective binding of the drug, or by producing tetracycline/macrolide-inactivating enzymes. Periodontal pathogens may become resistant to these drugs. Finally, metronidazole can be considered a prodrug in the sense that it requires metabolic activation by strict anaerobe microorganisms. Acquired resistance to this drug has rarely been reported. Due to these low rates of resistance and to its high activity against the gram-negative anaerobic bacterial species, metronidazole is a promising drug for treating periodontal infections.

Experimental alveolitis in rats: microbiological, acute phase response and histometric characterization of delayed alveolar healing

The pathogenesis of alveolitis is not well known and therefore experimental situations that mimic some features of this disease should be developed. OBJECTIVE: In this study, the evolution of the experimentally induced infection in rat sockets is characterized, which leads to clinical signs of suppurative alveolitis with remarkable wound healing disturbs. MATERIAL AND METHODS: Non-infected (Group I) and experimentally infected sockets in Rattus novergicus (Group II) were histometrically evaluated regarding the kinetics of alveolar healing. In addition, the characterization of the present bacteria in inoculation material and the serum levels of C-reactive protein (CRP) were performed. The detected species were Capnocytophaga ochracea, Fusobacterium nucleatum ss nucleatum, Prevotella melaninogenica, Streptococcus anginosus, Treponema socranskii and Streptococcus sanguis. RESULTS: All experimentally infected rats developed suppurative alveolitis, showing higher levels of CRP in comparison to those non-infected ones. Furthermore, infected rats presented a significant delayed wound healing as measured by the histometric analysis (higher persistent polymorphonuclear infiltrate and lower density of newly formed bone). CONCLUSION: These findings indicate that rat sockets with experimentally induced infection produced higher levels of serum CRP, showing the potential of disseminated infection and a disturb in the alveolar repair process in an interesting experimental model for alveolitis studies.