Incorporation of zinc into cetylpyridinium chloride mouthwash affects the composition of multispecies biofilms.

This study evaluated the effect of a mouthwash containing 0.075% cetylpyridinium chloride and 0.28% zinc lactate (CPC + Zn) in a multispecies biofilm model. A 7-days 33-species biofilm, formed on Calgary device, was 1-min treated with: 0.12% chlorhexidine (CHX), culture medium (negative control), 0.075% cetylpyridinium chloride (CPC) or CPC + Zn, 2x/day, from day 3 until day 6. The metabolic activity and the microbial composition were evaluated by colorimetric method and checkerboard DNA-DNA hybridization, respectively. The three antimicrobials (CPC, CPC + Zn and CHX) reduced metabolic activity, total biofilm count and several species counts, including Porphyromonas gingivalis, Fusobacterium nucleatum, Parvimonas micra, Campylobacter gracilis and Streptococcus mutans. However, only CPC + Zn reduced counts of the pathogen Prevotella intermedia and did not interfere with the levels of some beneficial species in relation to the negative control. The treatment of multispecies subgingival biofilm with CPC + Zn was effective in controlling periodontal pathogens and favored the colonization of health-associated bacterial species.

Association of different antidepressant classes with clinical attachment level and alveolar bone loss in patients with periodontitis: A retrospective study.

OBJECTIVE: Our study aimed to determine the relationship of antidepressant medicine use with periodontal diseases, exploring the association of different pharmacological classes of antidepressant with observations of clinical attachment loss (CAL) and alveolar bone level (BL) in patients with periodontitis. BACKGROUND: Existing evidence on the impact of antidepressant medication on periodontal tissues has focused on some classes only and is still unclear. Therefore, this retrospective study evaluated the association of different antidepressant classes with clinical attachment loss (CAL) and alveolar bone level (BL). METHODS: This study was carried out in a population of patients aged ≥ 30 years old with periodontitis who sought treatment at the University of Florida from 2014 to 2018. The following variables were obtained from patients' records; usage of antidepressant medications and their pharmacological classes (selective serotonin reuptake inhibitors [SSRI], serotonin-norepinephrine reuptake inhibitors [SNRI], tricyclic, atypical, and monoamine oxidase inhibitors [MAO]), age, gender, smoking habit, mild systemic diseases, CAL, and cement-enamel junction (CEJ) and alveolar bone crest (BC) distance, defined as BL, in the Ramfjord index teeth. RESULTS: Five hundred and eighty-two periodontitis patients were evaluated, of which 113 (19.4%) were antidepressant users. Antidepressant users exhibited significantly lower BL and fewer sites with severe CAL (≥5 mm), than non-users (p < .05). Among all single-class antidepressant users, the SSRI users showed significantly less CAL and lower BL than non-users (p < .05). Patients taking combinations of the different classes of antidepressants also showed better CAL and BL than non-users. Generalized linear models, including variables such as gender, age, systemic diseases, and smoking, demonstrated that antidepressant users were more likely to have lower mean BL and fewer sites with severe bone loss (i.e. BL > 3 and >5 mm) than non-users (p < .05). CONCLUSIONS: Antidepressant medications were associated with higher alveolar bone level and less clinical attachment loss in patients with periodontitis. When the different classes of antidepressants were analyzed individually, only the SSRI class users and the multiple-class users showed significantly less periodontal breakdown than non-users.

Adverse events of metronidazole and amoxicillin: Retrospective analysis of a large data set of five randomized clinical trials.

AIM: To evaluate the frequency of side effects associated with intake of metronidazole (MTZ) + amoxicillin (AMX) in periodontal treatment, and to explore associations between these events and patients' features. MATERIALS AND METHODS: Data of five randomized clinical trials testing MTZ + AMX adjunctive to mechanical therapy were evaluated. Volunteers answered an adverse event questionnaire. RESULTS: Information from 656 subjects was assessed. The frequency of side effects in the antibiotic- and placebo-treated groups ranged from 1.0% to 17.7% and 0.9% to 13.7%, respectively. The events more frequently observed in the antibiotic than in the placebo group were diarrhoea and metallic taste (p < .05). Diabetes significantly raised the odds of a patient reporting discomfort (odds ratio [OR] = 2.6), diarrhoea (OR = 4.0), weakness (OR = 6.0) and excessive sleepiness (OR = 2.9). In systemically healthy volunteers, using antibiotics 3 months post-mechanical treatment (healing phase) (OR = 3.0), being a woman (OR = 3.9) and aged ≤49 (OR = 4.5) significantly increased the chances of reporting adverse events. CONCLUSIONS: The occurrence of side effects during MTZ + AMX treatment ranged from uncommon (1%) to very common (17.7%). The main factors raising the chances of a patient reporting adverse events were diabetes and taking antibiotics in the healing phase, instead of in the active phase of treatment. Patients ≤ 49 years old and females also tend to report more side effects.

Assessment of the bone thickness of the palate on cone-beam computed tomography for placement of miniscrew-assisted rapid palatal expansion appliances.

INTRODUCTION: The correction of maxillary transverse discrepancy is achieved by means of rapid maxillary expansion, which may be performed by conventional or surgically-assisted rapid maxillary expansion, and more recently, by miniscrew-assisted rapid palatal expansion (MARPE). This study assessed the bone thickness of the palate on cone-beam computed tomography (CBCT) images for placement of mini-implants and anchorage of MARPE. METHODS: The sample consisted of 223 CBCT scans from patients of both genders (137 females and 86 males) aged ≥18 years. By using the Image Studio software (Anne Solutions, São Paulo, Brazil), measurements of the bone thickness of the palate were performed bilaterally, as follows: in the axial plane, the bone thicknesses were determined in the anterior region (distal face of the first premolars) and the posterior region (distal face of the first molars), at 3 mm and 6 mm laterally to the midpalatal suture. So in the sagittal plane, the bone thicknesses of the palate were measured in these placements from the palatal cortical to the nasal floor cortical in the anterior region at 30°, 45°, and 90°. In the posterior region, the bone thickness was determined only at 90°. The statistical tests used were the Kruskal-Wallis H test (analysis of variance on ranks) with Dunn's post-hoc test and Mann-Whitney U test (P <0.05). RESULTS: The bone thickness of the palate in the anterior region varied from 8.57 mm in women to 11.28 mm in men at 3 mm from the midpalatal suture and from 7.99 mm in women to 10.47 mm in men at 6 mm for 30°; from 6.35 mm in women to 9.28 mm in men at 3 mm from the midpalatal suture and from 6.20 mm in women to 8.88 mm in men at 6 mm for 45°; from 4.51 mm in women to 6.85 mm in men at 3 mm from the midpalatal suture and from 4.29 mm in women to 6.64 mm in men at 6 mm for 90°. In the posterior region, the bone thickness varied from 2.93 mm (3 mm from the suture) to 1.78 mm (6 mm from the suture) for women and from 3.24 mm (3 mm from the suture) to 1.99 mm (6 mm from the suture) for men. In general, the bone thickness of the palate is greater in the anterior region at 3 mm from the midpalatal suture at 30°. CONCLUSIONS: There was high variability in the bone thickness of the palate among patients and in different areas. Therefore, it is necessary to make an individualized diagnosis of the patient and manufacture the MARPE appliance carefully by performing a prior evaluation of the palatal bone thickness by means of CBCT to determine the ideal sites and inclinations for placement of mini-implants.

Effects of strontium ranelate on ligature-induced periodontitis in estrogen-deficient and estrogen-sufficient rats.

BACKGROUND AND OBJECTIVES: Strontium ranelate is a medication indicated for the treatment of osteoporosis that presents concomitant anti-resorptive and osteoanabolic dual biological activity. However, the effects of strontium ranelate on alveolar bone have been poorly explored. Furthermore, to date, there are no data on the effects of this medication on alveolar bone loss (BL) during conditions of estrogen deficiency. Therefore, the aim of this study was to evaluate the effects of strontium ranelate on ligature-induced periodontitis in estrogen-deficient and estrogen-sufficient rats. METHODS: Ninety-six rats were assigned to one of the following groups: sham-surgery + water (estrogen-sufficient; n = 24); ovariectomy + water (estrogen-deficient; n = 24), sham-surgery + strontium ranelate (ranelate/estrogen-sufficient; n = 24) and; ovariectomy + strontium ranelate (ranelate/estrogen-deficient; n = 24). The rats received strontium ranelate or water from the 14th day after ovariectomy until the end of the experiment. On the 21st day after ovariectomy, one first mandibular molar received a ligature, while the contralateral tooth was left unligated. Eight rats per group were killed at 10, 20, and 30 days after ligature placement. Bone loss (BL) and trabecular bone area (TBA) were analyzed in the furcation area of ligated and unligated teeth at all experimental times by histometry. Tartrate-resistant acid phosphatase (TRAP) positive cells and immunohistochemical staining for osteocalcin (OCN), osteopontin (OPN), osteoprotegerin (OPG), and receptor activator of NF-КB ligand (RANKL) were assessed in the ligated teeth at 30 days after ligature placement. RESULTS: At 10 and 30 days, ligated teeth of the estrogen-deficient group exhibited higher BL, when compared to all other groups (P < .05). At 10 days, TBAs were higher in the unligated teeth of strontium ranelate-treated groups, when compared to those of untreated groups (P < .05). At 30 days, the ligated teeth of the estrogen-deficient group exhibited lower TBA than the other groups (P < .05). There were no differences among groups regarding the number of TRAP-stained cells (P < .05). The strontium ranelate-treated groups exhibited lower expressions of OCN and RANKL than the untreated groups (P < .05). The estrogen-sufficient group presented higher staining for OPG than both treated and untreated estrogen-deficient groups (P < .05). CONCLUSIONS: Strontium ranelate prevented ligature-induced BL in an estrogen-deficiency condition and, to a certain extent, increased TBA in the presence and absence of periodontal collapse in states of estrogen deficiency and estrogen sufficiency. Furthermore, strontium ranelate also affected the expression of bone markers, appearing to have acted predominantly as an anti-resorptive agent.

Might smoking assuage the pro-inflammatory effect of diabetes in periodontal sites?

OBJECTIVES: This study evaluated the effects of type 2 diabetes mellitus (DM), smoking, and these two factors combined on gingival crevicular fluid levels and ratios of pro-/anti-inflammatory cytokines. Associations between cytokines with each other and with key periodontal pathogens in periodontal sites under the challenge of one or both of these risk factors were also assessed. METHODS: A total of 102 subjects with periodontitis were included in this cross-sectional study and assigned to one of the following groups: non-diabetic non-smokers (control group, n = 25), non-smokers with DM (DM group, n = 30), non-diabetic smokers (S group, n = 26), and smokers with DM (S + DM group, n = 21). The levels of 13 pro-inflammatory (IFN-γ, TNF-α, MIP-1α, GM-CSF, IL-1ß, IL-2, IL-6, IL-7, IL-8, IL-12, IL-17, IL-21, and IL-23) and 5 anti-inflammatory (IL-4, IL-5, IL-10, IL-13, and TGF-ß) cytokines were assessed in healthy and diseased sites, using multiplex immunoassay. Ratios of pro-/anti-inflammatory cytokines were obtained in all possible permutations. The levels of 7 key periodontal pathogens were evaluated by qPCR. RESULTS: Overall, the ratios of pro-/anti-inflammatory cytokines were higher in healthy and diseased sites of the DM group and in healthy sites of the S + DM group, and lower in diseased sites of the S group, compared with the control (p < .05). The proportion of the pro-inflammatory cytokines in relation to the 18 cytokines studied was higher in the DM group and lower in the S group, whereas the proportion of the anti-inflammatory cytokines was lower in both diabetic groups and higher in the S group, compared to the control (p < .05). A cluster of six common cytokines (IL-4, IL-5, IL-12, IL-13, IL-21, and IL-23) was observed in the diseased sites of all groups studied. Eight common cytokines (IL-4, IL-5, IL-12, IL-13, IL-17, IL-21, IL-23, and IFN-γ) grouped closely in the healthy sites of both diabetic groups. Significant associations between pathogens and cytokines occurred mainly in the diseased sites of the S + DM group (p < .05). CONCLUSION: Diabetes mellitus induced an overall pro-inflammatory state, while smoking mainly stimulated immunosuppression in periodontal sites. When the two risk factors overlapped, smoking seemed to partially assuage the hyperinflammatory effect of DM.

An in vitro assessment of the influences of different wire materials and bracket systems when correcting dental crowding.

A recently developed orthodontic wire alloy known as GUMMETAL® is claimed to deliver more physiological forces to correct dental mispositioning. However, its mechanical characteristics have not been fully characterized yet. This study aimed to determine and compare the elastic properties of different wire alloys, such as nickel-titanium (NiTi), stainless steel (SS), and GUMMETAL®, and assess their unloading forces when combined with either conventional or self-ligating brackets (CL and SL) when correcting dental crowding. All wires had a 0.016″ cross-section diameter. A three-point bending test was performed to assess the maximum deflection of each wire. Then, a subsequent analysis measured the unloading force for each wire/bracket system in a dental crowding clinical simulation device. The test was carried out in a universal testing machine with a cross-speed displacement of 0.5 mm/min. Data were recorded in different ranges and statistically evaluated using two-way analysis of variance. GUMMETAL® displayed higher unloading mean forces in SL brackets (2228.78 cN) than CL brackets (1967.38 cN) for the 1.6-3.0 deflection interval (p = 0.018). Within this interval, NiTi showed higher forces when used with CL brackets (2683.06 cN) than with SL brackets (1179.66 cN) (p < 0.0001). For the CL bracket systems, SS wires showed higher forces (2125.31 cN) in the 1.0-1.6 deflection interval than the other two wire alloys (NiTi, 1541.52 cN and GUMMETAL®, 852.65 cN) (p < 0.0001). SS wires also displayed lower forces with SL brackets (1844.01 cN) than in CL brackets (2125.31 cN) (p = 0.049). Thus, only GUMMETAL® revealed to be an optimal choice for SL brackets, whereas NiTi for CL brackets.

Brazilian red propolis reduces orange-complex periodontopathogens growing in multispecies biofilms.

This study investigated the antimicrobial effects of the ethanolic extract of Brazilian red propolis (BRP) on multispecies biofilms. A seven-day-old subgingival biofilm with 32 species was grown in a Calgary device. Biofilms were treated with BRP (1,600, 800, 400 and 200 µg ml-1) twice a day for 1 min, starting from day 3. Chlorhexidine (0.12%) and dilution-vehicle were used as positive and negative controls, respectively. On day 7, metabolic activity and the microbial composition of the biofilms by DNA-DNA hybridization were determined. The viability data were analyzed by one-way ANOVA followed by Tukey's post hoc, whereas the microbial composition data were transformed via BOX-COX and analyzed using Dunnett's post hoc. BRP (1,600 µg ml-1) decreased biofilm metabolic activity by 45%, with no significant difference from chlorhexidine-treated samples. BRP (1,600 µg ml-1) and chlorhexidine significantly reduced levels of 14 bacterial species compared to the vehicle control. Taken together, BRP showed promising antimicrobial properties which may be useful in periodontal disease control.

The ratios of pro-inflammatory to anti-inflammatory cytokines in the serum of chronic periodontitis patients with and without type 2 diabetes and/or smoking habit.

OBJECTIVE: This study assessed the impact of chronic periodontitis (CP) and CP associated with type 2 diabetes mellitus (DM) and/or smoking on the serum ratios of pro- to anti-inflammatory cytokines. MATERIALS AND METHODS: Subjects were assigned into one of the following groups: control (n = 25, non-diabetic non-smokers with no history of periodontitis), CP (n = 26, non-diabetic non-smokers with CP), DMCP (n = 30, non-smokers with DM and CP), SCP (n = 27, non-diabetic smokers with CP), and SDMCP (n = 22, smokers with type 2 DM and CP). Serum levels of 18 cytokines were measured using multiplex immunoassays. RESULTS: Six ratios of pro-inflammatory to anti-inflammatory cytokines were significantly higher in the CP group than in the control group (p < 0.05). Eleven, seventeen and nine ratios of pro-inflammatory to anti-inflammatory cytokines were significantly higher in the DMCP, SCP and SDMCP groups than in the control group, respectively (p < 0.05). The SCP group presented higher serum ratios of tumor necrosis factor (TNF)-α/interleukin (IL)-4, TNF-α/IL-5, IL-17/IL-13 and IL-6/IL-13 (p < 0.05) than the CP group. Cluster analysis revealed a relevant cluster composed of ten cytokines (IL-17, IL-23, interferon-γ, IL-12, IL-1ß, IL-2, IL-21, IL-6, IL-4 and granulocyte-macrophage colony-stimulating factor [GM-CSF]) in the serum of subjects from the DMCP group. CONCLUSIONS: The ratios of pro- to anti-inflammatory cytokines shift to favor a pro-inflammatory status in the serum of patients with CP and even more when CP is associated with one or both risk factors. CLINICAL RELEVANCE: CP and CP associated with hyperglycemia and/or smoking might contribute to a systemic inflammatory burden and increased risk of systemic complications.

Antagonists of Wnt/ß-catenin signalling in the periodontitis associated with type 2 diabetes and smoking.

AIM: This study evaluated the levels of sclerostin (SOST) and Dickkopf (DKK)-1 in the chronic periodontitis (CP) associated with type 2 diabetes (DM) and/or smoking. Relationships between SOST, DDK1, RANKL, OPG, IL-1ß, IL-6 and TNF-α, and pathogens were assessed. MATERIAL AND METHODS: The study population included non-diabetic non-smokers (control), non-smokers with DM (DM group), non-diabetic smokers (S group) and smokers with DM (SDM group), all with CP. Serum and gingival levels of SOST, DKK1, RANKL, OPG, IL-1ß, IL-6 and TNF-α were evaluated by multiplex immunoassay. Gene expressions of these biomarkers and subgingival levels of pathogens were assessed by qPCR. RESULTS: Gingival protein and/or mRNA levels of DKK1 and SOST were higher in subjects with DM and/or smoking than in controls (p < .05). Serum levels of SOST were higher in the DM group than in controls (p < .05). DKK1 positively correlated with SOST in the DM, SDM and control groups (p < .05) at mRNA levels. DKK-1 and SOST correlated with pathogens, especially in both groups with DM. CONCLUSIONS: SOST and DKK1 were upregulated in patients with CP presenting DM and/or smoking. DM, alone or with smoking, particularly influenced the correlations of SOST and DKK1 with each other and with the other biomarkers mostly at mRNA levels, as well as with periodontal pathogens.

A Bayesian approach to model the conditional correlation between several diagnostic tests and various replicated subjects measurements.

Two key aims of diagnostic research are to accurately and precisely estimate disease prevalence and test sensitivity and specificity. Latent class models have been proposed that consider the correlation between subject measures determined by different tests in order to diagnose diseases for which gold standard tests are not available. In some clinical studies, several measures of the same subject are made with the same test under the same conditions (replicated measurements), and thus, replicated measurements for each subject are not independent. In the present study, we propose an extension of the Bayesian latent class Gaussian random effects model to fit the data with binary outcomes for tests with replicated subject measures. We describe an application using data collected on hookworm infection carried out in the municipality of Presidente Figueiredo, Amazonas State, Brazil. In addition, the performance of the proposed model was compared with that of current models (the subject random effects model and the conditional (in)dependent model) through a simulation study. As expected, the proposed model presented better accuracy and precision in the estimations of prevalence, sensitivity and specificity. Copyright © 2017 John Wiley & Sons, Ltd.

Does obesity influence the subgingival microbiota composition in periodontal health and disease?

AIM: To evaluate whether obesity affects the subgingival microbial composition of patients with periodontal health or chronic periodontitis (CP). MATERIALS AND METHODS: Based on periodontal parameters, body mass index and waist-hip ratio, 166 patients were allocated into one of the following groups: Normal weight (NW) patients with periodontal health (n = 44), NW patients with CP (n = 40), obese patients with periodontal health (n = 40) and obese patients with CP (n = 42). Six subgingival biofilm samples per patient were analysed for their content of 40 bacterial species using checkerboard DNA-DNA hybridization. RESULTS: Obese patients with CP harboured higher levels and/or higher proportions of several periodontal pathogens than those with NW and CP, including Aggregatibacter actinomycetemcomitans, Eubacterium nodatum, Fusobacterium nucleatum ss vincentii, Parvimonas micra, Prevotella intermedia, Tannerella forsythia, Prevotella melaninogenica and Treponema socranskii. The proportions of most of these pathogens, as well Campylobacter rectus and Eikenella corrodens, were more increased in the diseased sites of the obese patients than in those with NW. Furthermore, the healthy sites of the obese patients, presenting or not CP, also exhibited higher proportions of some of the pathogens than patients with NW. CONCLUSIONS: Obesity is associated with increased levels and proportions of periodontal pathogens, especially in patients with CP.

Local and serum levels of adipokines in patients with obesity after periodontal therapy: one-year follow-up.

AIM: This study evaluated the effects of scaling and root planing (SRP) on gingival crevicular fluid (GCF) and serum levels of adipokines in patients with chronic periodontitis (CP) with or without obesity. METHODS: Twenty patients with obesity and 20 patients without obesity, all with CP, received SRP. Serum and GCF levels of resistin, adiponectin, leptin, tumour necrosis factor [TNF]-α and interleukin [IL]-6 were evaluated by enzyme-linked immunosorbent assay at baseline, 3, 6 and 12 months post-therapy. RESULTS: SRP reduced the amounts of TNF-α in deep sites and increased the concentration of adiponectin in shallow sites of non-obese patients (p < 0.05). SRP increased the concentrations of TNF-α and leptin in patients with obesity (p < 0.05). GCF levels of TNF-α were higher in patients with obesity than in patients without obesity at all time-points (p < 0.05). There were no changes in serum levels of any adipokines for any group after therapy (p > 0.05). Patients with obesity exhibited higher serum levels of leptin at all time-points and IL-6 at 3 months post-therapy (p < 0.05). CONCLUSIONS: Obesity may modulate systemic and periodontal levels of adipokines in favour of pro-inflammation, independently of periodontal therapy. SRP did not affect the circulating levels of adipokines in patients with or without obesity.

Effects of Osseodensification on Primary Stability of Cylindrical and Conical Implants-An Ex Vivo Study.

Primary stability is an important factor for dental implant success. In the past years, a new method for bone site preparation was introduced, named osseodensification (OD). OD produces a condensation of the trabecular portion of the bone, increasing bone-to-implant contact and primary stability. This study aims to compare the effect of OD in cylindrical and conical implants to conventional instrumentation. A total of forty implants, divided into four groups, were placed in porcine tibia: cylindrical conventional (1a), cylindrical OD (1b), conical conventional (2a) and conical OD (2b). Each implant was measured for implant stability quotient (ISQ), insertion torque (IT) and removal torque (RT). Group 2b showed the higher values for each of the evaluated parameters; groups 1b and 2b showed better results than 1a and 2a, respectively. Regarding the IT and RT, group 1b achieved higher values than group 2a, but not for ISQ. The inter-group comparison showed significant difference between groups 1a vs 2a, 1a vs 2b and 1b vs 2b for ISQ and 1a vs 1b and 1a vs 2b for RT analysis. OD resulted in improved ISQ, IT and RT of both cylindrical and conical implants.

Effects of different antidepressant classes on dental implant failure: A retrospective clinical study.

BACKGROUND: Previous studies have suggested an association between taking antidepressants and dental implant failure. This study aimed to investigate the association of different antidepressant classes with dental implant failure. METHODS: This retrospective study included patients that received dental implants at the University of Florida from 2011 to 2016. The variables of implant failure, antidepressant use and classes (selective serotonin reuptake inhibitors [SSRI], serotonin-norepinephrine reuptake inhibitors [SNRI], tricyclic antidepressants [TCA], atypical antidepressants [AA], and monoamine oxidase inhibitors [MAOI]), age, sex, smoking, mild systemic diseases, and implant location were obtained from patients' records. Odds ratio (OR) and confidence interval (CI) of implant failure in patients taking different antidepressant classes, in relationship to non-antidepressant users, were estimated, and the influence of multiple variables on implant failure were investigated. RESULTS: A total of 771 patients and 1,820 implants were evaluated. The statistically significant predictors for implant failure included smoking (OR = 5.221), use of antidepressants (OR = 4.285), posterior maxilla location (OR = 2.911), mild systemic disease (OR = 2.648), and age (OR = 1.037) (P <0.05). The frequency of implant failure was 33.3% in TCA users, 31.3% in SNRI users, 6.3% in SSRI users, 5.2% in Atypical antidepressant users, and 3.9% in non-users. Significant associations were observed between the use of SNRI (OR: 11.07; 95% CI: 3.265 to 33.82) and TCA (OR: 12.16; 95% CI: 1.503 to 71.58) and implant failure (P <0.05). CONCLUSIONS: Users of antidepressants were at higher risk of implant failure than non-users. Patients taking SNRI and TCA were at the highest risk of implant loss, when compared with non-users. Conclusions about TCA, however, are based on a limited number of cases.

Metronidazole and amoxicillin for patients with periodontitis and diabetes mellitus: 5-year secondary analysis of a randomized controlled trial.

BACKGROUND: The aim of this study was to perform a 5-year follow-up analysis of a previously-published randomized trial (RCT) evaluating the 2-years effects of metronidazole (MTZ) plus amoxicillin (AMX) as adjuncts to scaling and root planing (SRP) in the treatment of periodontitis in type 2 diabetic patients. METHODS: Volunteers who received periodontal treatment in the aforementioned RCT were selected for clinical and microbiological evaluation. Patients did not receive regular supportive periodontal therapy (SPT) from 2 to 5 years post-treatment. RESULTS: Of the patients enrolled in the RCT, 43% entered this study (n = 10/control and 15/test group). Most of clinical parameter values, including the number of sites with probing depth ≥ 5 mm (primary outcome variable), were reduced at 5 years post-therapy when compared with baseline in the antibiotic-treated group (P < 0.05), but presented higher values than those at 2 years (P < 0.05). The mean proportions of microbial complexes did not differ between MTZ+AMX+SRP and SRP-only groups at 5 years post-treatment (P > 0.05). CONCLUSION: Diabetic patients treated with adjunctive MTZ+AMX were better maintained over a period of 5 years than those treated with SRP only. However, the clinical and microbiological benefits obtained up to 2 years post-treatment were not fully sustained in these patients who did not receive SPT between 2 and 5 years post-treatment.

Brazilian Red Propolis Is as Effective as Amoxicillin in Controlling Red-Complex of Multispecies Subgingival Mature Biofilm In Vitro.

This study investigated the effects of Brazilian Red Propolis (BRP) extract on seven-day-old multispecies subgingival biofilms. Mixed biofilm cultures containing 31 species associated with periodontal health or disease were grown for six days on a Calgary device. Then, mature biofilms were treated for 24 h with BRP extract at different concentrations (200-1600 µg/mL), amoxicillin (AMOXI) at 54 µg/mL (positive control) or vehicle (negative control). Biofilm metabolic activity was determined by colorimetry, and bacterial counts/proportions were determined by DNA-DNA hybridization. Data were analyzed by Kruskal-Wallis and Dunn's tests. Treatment with BRP at 1600, 800 and 400 µg/mL reduced biofilm metabolic activity by 56%, 56% and 57%, respectively, as compared to 65% reduction obtained with AMOXI. Mean total cell counts were significantly reduced in all test groups (~50-55%). Lower proportions of red, green and yellow complex species were observed upon treatment with BRP (400 µg/mL) and AMOXI, but only AMOXI reduced the proportions of Actinomyces species. In conclusion, BRP extract was as effective as AMOXI in killing seven-day-old multispecies biofilm pathogens and did not affect the levels of the host-compatible Actinomyces species. These data suggest that BRP may be an alternative to AMOXI as an adjunct in periodontal therapy. In vivo studies are needed to validate these results.

In vitro evaluation of enamel surface roughness and morphology after orthodontic debonding: Traditional cleanup systems versus polymer bur.

INTRODUCTION: The primary aim of this randomized in vitro study was to compare the effectiveness of carbide, fibreglass and polymer burs on resinous remnant removal after bracket debonding, by the evaluation of enamel surface roughness and morphology. The secondary objective was to compare the time dispended on the procedures. METHODS: The buccal surfaces of 28 bovine incisors were analysed by a profilometer to initial roughness measurement (Ra-T1). Brackets were bonded with a light-cured resin and debonded with a debonding plier. The samples were randomly divided into four groups, according to the bur used (n=7): A-Tungsten carbide; B-Fibreglass; C-Polymer; D-Polymer with 75% ethanol pre-treatment. The second roughness measurements were made after resin removal (Ra-T2). Time for removal procedures was also recorded. The third measurements were made after polishing (Ra-T3). Scanning Electronic Microscopy was performed in two samples of each group: after resin removal and after polishing. Results of roughness and time measurements were statically analysed by analysis of variance with post-hoc Bonferroni. RESULTS: After polishing, tungsten carbide (P=0.1555) and fibreglass burs provided final surface roughness statistically similar to the baseline condition (P=1.0000). Yet, polymer burs, associated (P<0.0001) or not to alcohol (P<0.0001), provided surface roughness significantly higher when compared to baseline values. Polymer burs were more time-consuming on resinous remnant removal than tungsten carbide and fibreglass burs (P<0.05). CONCLUSION: Polymer burs were less effective and more time-consuming to remove the remaining resin than tungsten carbide and fibreglass burs. The polishing step created smoother surfaces regardless of the burs used for resin removal.

Prevalence and Diagnosis of Latent Tuberculosis Infection in Young Children in the Absence of a Gold Standard.

INTRODUCTION: For adequate disease control the World Health Organization has proposed the diagnosis and treatment of latent tuberculous infection (LTBI) in groups of risk of developing the disease such as children. There is no gold standard (GS) test for the diagnosis of LTBI. The objective of this study was to estimate the prevalence of LTBI in young children in contact with a household case of tuberculosis (TB-HCC) and determine the accuracy and precision of the Tuberculin Skin Test (TST) and QuantiFERON-TB Gold in-tube (QFT) used in the absence of a GS. METHODS: We conducted a cross-sectional study in children up to 6 years of age in Manaus/Brazil during the years 2009-2010. All the children had been vaccinated with the BCG and were classified into two groups according to the presence of a TB-HCC or no known contact with tuberculosis (TB). The variables studied were: the TST and QFT results and the intensity and length of exposure to the index tuberculosis case. We used the latent class model to determine the prevalence of LTBI and the accuracy of the tests. RESULTS: Fifty percent of the children with TB-HCC had LTBI, with the prevalence depending on the intensity and length of exposure to the index case. The sensitivity and specificity of TST were 73% [95% confidence interval (CI): 53-91] and 97% (95%CI: 89-100), respectively, versus 53% (95%CI: 41-66) and 81% (95%CI:71-90) for QFT. The positive predictive value of TST in children with TB-HCC was 91% (95%CI: 61-99), being 74% for QFT (95%CI: 47-95). CONCLUSIONS: This is one of the first studies to estimate the prevalence of LTBI in children and the parameters of the main diagnostic tests using a latent class model. Our results suggest that children in contact with an index case have a high risk of infection. The accuracy and the predictive value of the two tests did not significantly differ. Combined use of the two tests showed scarce improvement in the diagnosis of LTBI.

Análisis de flexión en alambres de níquel-titanio con y sin propiedades de transformación térmica / Bending analysis of nickel-titanium wires with and no thermal transformation properties

Objetivo: Evaluar el comportamiento de los alambres de aleación de níquel-titanio con y sin propiedades de transformación térmica en la relación carga/deflexión. Materiales y método: Para ello, 30 segmentos de alambres de níquel-titanio con calibre .014" y 30 mm de largo fueron cortados, conformando 10 segmentos de alambre Flexy NiTi de Orthometric®, 10 segmentos Flexy Copper NiTi termoactivado y 10 segmentos CuNiTi de OrmcoTM. Se usó una máquina universal de ensayos Instron® para analizar el comportamiento de carga y deflexión de los segmentos en una prueba de tres puntos, registrando las fuerzas alcanzadas en 0,5 mm: 1 mm, 2 mm y 4 mm de deflexión. Resultados: Hubo una diferencia estadísticamente significativa entre todos los alambres y entre todas las deflexiones, ya que el alambre Flexy Cooper NiTi presentó la menor carga entre todas las deflexiones analizadas. Conclusión: Se concluye que los alambres termoactivados alcanzan fuerzas más leves, lo que los hace más apropiados para alineaciones iniciales, las cuales requieren un mayor rango de deflexión(AU)