Chronic alcohol and nicotine consumption as catalyst for systemic inflammatory storm and bone destruction in apical periodontitis

AIM

To assess the periapical alveolar bone pattern and the serum levels of proinflammatory cytokines, biochemical markers and metabolites in rats subjected to chronic alcohol and nicotine consumption and induced apical periodontitis.

METHODOLOGY

Twenty-eight male Wistar rats were divided into four groups: Control, Alcohol, Nicotine and Alcohol+Nicotine. The alcohol groups were exposed to self-administration of a 25% alcohol solution, while the other groups were given only filtered water. The nicotine groups received daily intraperitoneal injections of a nicotine solution (0.19 μL of nicotine/mL), whereas the other groups received saline solution. Periapical lesions were induced by exposing the pulps of the left mandibular first molars for 28 days. After euthanasia, the mandibles were removed and the percentage bone volume, bone mineral density, trabecular thickness, trabecular separation and trabecular number of the periapical bone were measured using micro-computed tomography images. Serum samples were collected for analysis of proinflammatory cytokines (IL-1β, IL-4, IL-6 and TNF-α), biochemical and metabolomic analysis. Statistical analysis was performed with a significance level of 5%. Nonparametric data were analysed using the Kruskal-Wallis test followed by Dunn's test, while one-way anova followed by Tukey's test was performed for parametric data.

RESULTS

The groups exposed to alcohol or nicotine consumption exhibited an altered bone pattern indicating lower bone density and higher levels of IL-1β, IL-6 and TNF-α compared to the Control group (p < .05). Significant differences were observed among the groups in the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase, cholesterol, triglycerides, urea, creatinine, albumin, uric acid, bilirubin and calcium. Metabolomic analysis revealed significant differences in glycine, phosphocholine, lysine, lactate, valine, pyruvate and lipids (CH2 CH2 CO), n(CH2 ) and n(CH3 ). Most of these parameters were even more altered in the simultaneous consumption of both substances compared to single consumption.

CONCLUSION

Alcohol and nicotine chronic consumption altered several metabolic markers, impaired liver and kidney function, increased the production of systemic proinflammatory mediators and harmed the periapical bone microarchitecture in the presence of apical periodontitis. The simultaneous consumption of alcohol and nicotine intensified these detrimental effects.

Effect of the progressive taper enlargement of buccal root canals of three-rooted maxillary molars: A stepwise micro-CT study

This study evaluated unprepared canal areas, volume of dentine removal, and dentine thickness after the progressive enlargement of the buccal canals of 22 maxillary molars, with and without the MB2, using instruments with the same tip size (0.25 mm) but 4 different tapers (0.03, 0.05, 0.06 and 0.08 v). Micro-CT scans were performed after each instrument. Data were compared using a general linear mixed model post hoc comparisons with Kenward-Roger for Wald F tests (α = 5%). After each treatment step, it was observed an increase in the percentage volume of removed dentine and a decrease in the unprepared areas and dentine thickness at the pericervical region of all canals (p < 0.05). The percentage reduction of dentine thickness in MB2 canal was higher than in the mesiobuccal and distobuccal canals (p < 0.05). Knowledge of pre-operative dimensions and dentine thickness before enlargement of buccal canals of maxillary molars is an important factor to avoid excessive dentine removal.

pH influences the volumetric change of calcium silicate- and epoxy resin-based root canal sealers: An ex vivo micro-CT study

This study assessed the influence of pH variation on the volumetric change of EndoSequence BC Sealer compared to AH Plus Jet. Eighteen single-rooted teeth were uniformly prepared and filled with one of the sealers. After 24-h storing, samples were scanned in a micro-CT device. Then, roots were immersed in 20 ml phosphate-buffered saline (PBS) with pH of 5, 7 or 12 at 37°C for 7 and 30 days and rescanned. Statistical analysis was performed using Shapiro-Wilk's test, one-way ANOVA and Tukey's or Student's t-tests (p < 0.05). Differences between sealers were observed only at neutral pH and after 30 days of acidic pH exposure, with a higher loss of EndoSequence (p < 0.05). After 7 days, alkaline pH reduced and increased the volumetric loss of EndoSequence and AH Plus, respectively, compared to neutral pH (p < 0.05). It can be concluded that the pH directly influenced the volumetric change of both tested root canal sealers in different ways.

Volumetric changes in root canal sealers in ex vivo and a novel animal model approach

AIM

This study aimed to evaluate the volumetric change of root canal sealers through micro-computed tomographic analysis using a novel in vivo model and to compare the results with those obtained using an ex vivo test.

METHODOLOGY

Eighteen single-rooted teeth were cut to 5 mm length from the root apex. The root canals were uniformly enlarged and filled with EndoSequence BC Sealer or AH Plus Jet root canal sealers. Samples were stored at 37°C and 95% relative humidity for 24 h and then scanned with a micro-CT device. Twelve samples (n = 6 for each sealer) were implanted in the subcutaneous tissue of Wistar rats, while six samples (n = 3 for each sealer) were immersed in 20 mL of phosphate-buffered saline (PBS) at 37°C at neutral pH. After 7 and 30 days, teeth were removed from subcutaneous tissue or PBS and rescanned. Statistical analysis of volume changes was performed using Shapiro-Wilk's test and independent t-test (p < .05).

RESULTS

AH Plus Jet had smaller volume changes (-2.2 to +0.77%) than EndoSequence BC Sealer (-2.0 to +4.0%) (p < .05), in the two tested models. The volume of the root canal sealers decreased over time (p < .05), in vivo. AH Plus Jet results varied between the in vivo and ex vivo results (p < .05), while EndoSequence BC Sealer presented similar volume losses for both experimental models (p > .05).

CONCLUSION

EndoSequence BC Sealer lost more volume than AH Plus Jet. The experimental conditions influenced the volumetric change of AH Plus Jet but not the EndoSequence BC Sealer. The ex vivo model should be further explored as a methodological alternative to assess the volumetric changes of root canal sealers without causing harm to animals.

What is the microbial profile in persistent endodontic infections? A scoping review

INTRODUCTION

This scoping review aimed to map the evidence about the microbiota found in persistent endodontic infections.

METHODS

The study protocol was prospectively registered and is available at https://osf.io/3g2cp. The electronic search was performed in MEDLINE via PubMed, Lilacs, BBO, Scopus, Web of Science, Cochrane Library and EMBASE. The eligibility criteria were based on the PCC acronym, where P (Population): patients with teeth presenting persistent endodontic infection; C (Concept): microbial profile; and C (Context): undergoing endodontic retreatment. Clinical studies that evaluated the microbial profile of samples collected from root canals of teeth undergoing retreatment, using classical or molecular methods, were included. Studies that did not show a minimum period of one year between primary endodontic treatment and retreatment or did not radiographically evaluate the quality of primary root canal filling were excluded. Two reviewers independently selected the articles and collected data.

RESULTS

From a total of 957 articles, 161 were read in full and 32 studies were included. The most prevalent species were Enterococcus faecalis, Parvimonas micra, Porphyromonas endodontalis, Porphyromonas gingivalis, Prevotella intermedia, Dialister invisus, Propionibacterium acnes, Tannerella forsythia and Treponema denticola. Cases with symptomatology or inadequate root canal filling presented an increase in specific bacterial species compared to no symptomatology or adequate filling. A greater number of microorganisms was observed in teeth with inadequate coronal restoration compared to adequate restoration.

CONCLUSION

Persistent endodontic infections have a polymicrobial profile identified by the commonly used methods for bacterial detection/identification and are subject to the limitations present in each of those methods.

Association between Apical Periodontitis and Chronic Diseases: An Umbrella Review

Introduction

To assess the methodological quality of systematic reviews (SRs) that evaluated the association between apical periodontitis (AP) and chronic diseases.

Materials and Methods

A systematic search was performed in the databases PubMed, Virtual Health Library, Scopus, Cochrane Library, Embase, Web of Science and Open Grey. SRs that evaluated the association between any chronic disease and AP, and that had performed a valid risk of bias assessment were included. The AMSTAR-2 tool was used for quality assessment and each included systematic review received a final categorization as having "high", "moderate", "low", or "critically low" quality.

Results

Nine studies that met the eligibility criteria were included. The diseases investigated were cardiovascular diseases, diabetes mellitus, HIV, osteoporosis, chronic liver disease, blood disorders and autoimmune diseases. The systematic reviews included in this umbrella review showed a 'low' to 'high' quality of evidence.

Conclusion

There are substantial heterogeneity and several methodological concerns in the included studies. It was observed a positive association between diabetes mellitus and apical periodontitis with limited evidence, no association between HIV and apical periodontitis and a positive association between apical periodontitis and cardiovascular disease, blood disorders, chronic liver disease, osteoporosis and autoimmune diseases with moderate evidence.

Impact of minimally invasive endodontics procedures on the development of dentinal microcracks

INTRODUCTION

To evaluate the impact of root canal preparation in teeth with ultraconservative access cavities (UltraAC) on the development of dentinal microcracks using a non-destructive longitudinal micro-CT imaging experimental model. Root canal preparation in teeth with traditional access cavities (TradAC) was used as control.

METHODS

Forty mandibular molars were scanned in a micro-CT device, anatomically matched, and distributed into 4 groups according to the type of access cavity and instrumentation system: traditional/Reciproc (TradAC/RC); traditional/XP-endo Shaper (TradAC/XP); ultraconservative/Reciproc (UltraAC/RC) and ultraconservative/XP-endo Shaper (UltraAC/XP). After root canal preparation, the teeth were rescanned. After reconstruction and co-registration procedures, the images were screened from the furcation level to the apex to identify the presence of dentinal microcracks.

RESULTS

From a total of 15340 cross-section images, 19.65% (3014 slices) had some dentinal microcrack. The qualitative analysis demonstrated the presence of some dentinal microcrack in 11%, 33%, 19%, and 15% of the images of cross-sections in TradAC/RC, TradAC/XP, UltraAC/RC, and UltraAC/XP groups, respectively. All dentinal microcracks observed after root canal preparation were already present in the corresponding images before canal instrumentation. Therefore, no new microcracks were detected, regardless of the access cavity and root canal instrumentation system.

CONCLUSIONS

Root canal preparation with Reciproc or XP-Endo Shaper under traditional or ultraconservative access cavities did not create dentinal microcracks in extracted mandibular molars.

Photodynamic therapy for root canal disinfection in endodontics: an umbrella review

To evaluate and synthesize the evidence from the individual reviews that evaluated the efficacy of PDT therapy in root canal disinfection by undertaking an umbrella review. The protocol of the review was registered in the PROSPERO database under number CRD42021214056. The literature search was conducted using the following electronic databases: PubMed, Scopus, Web of Science, BVS, Cochrane Database of Systematic Reviews, Embase, and Epistemonikos, from inception to July 2021. Systematic reviews that evaluated the efficacy of PDT for root canal disinfection were included. Two authors independently performed a literature search, data extraction, and quality assessment of the included studies. Any disagreements were resolved by a third reviewer. The quality of the reviews was assessed using the AMSTAR 2 tool and the final categorization of each systematic reviews was classified as of "high," "moderate," "low," or "critically low" quality. Six systematic reviews were included in the current umbrella review and all of them were graded as critically low quality. From the critically low-quality evidence available, this umbrella review showed that the efficacy of PDT in root canal disinfection remains yet undetermined.

The impact of TruNatomy and ProTaper Gold instruments on the preservation of the periradicular dentin and on the enlargement of the apical canal of mandibular molars

INTRODUCTION

This study aimed to evaluate the preservation of the periradicular dentin and the enlargement of the apical canal of mandibular molars with TruNatomy and ProTaper Gold instruments.

METHODS

Twenty mandibular molars were scanned in a micro-CT device, anatomically paired, and distributed into 2 groups (n=10). In the ProTaper Gold group, mesial and distal canals were prepared up to F2 (25/.08v) and F3 (30/.09v) instruments, while in the TruNatomy group, mesial and distal canals were enlarged until Prime (26/.04v) and Medium (36/.03v) instruments, respectively. After a new scan, surface area, volume, unprepared areas, transportation, percentage of dentin removal, and dentin thickness parameters were calculated. Data were compared between groups using Mann-Whitney, Student t-test, and the non-metric multidimensional scaling test with alpha set at 5%.

RESULTS

No difference was found between groups regarding unprepared canal areas and reduction of dentin thickness (P > 0.05). Transportation was lower than 0.1 mm in all groups and statistical differences were observed only at the apical third of the mesiobuccal canal with lower values in the TruNatomy group. ProTaper Gold removed more dentin than TruNatomy at the coronal level of mesial roots (1.8% and 1.0%, respectively) (P < 0.05).

CONCLUSIONS

TruNatomy and ProTaper Gold were efficient for performing canal preparation in mandibular molars. The tested systems were similar in terms of untouched canal walls and remaining dentin thickness, and slightly different in the apical transportation of mesial canals and percentage of dentin removal at the coronal third, but without clinically significant errors.

Effect of passive ultrasonic irrigation on hard tissue debris removal: a systematic review and meta-analysis

Accumulated hard tissue debris (AHTD) in root canal irregularities may negatively impact adequate root canal disinfection. In light of this, the efficacy of passive ultrasonic irrigation (PUI) to reduce AHTD has been largely studied in in vitro studies, which have adopted different analytic methods of varying accuracy to determine the extent of AHTD more correctly. Therefore, the aim of this study was to compare how well PUI and non-activated irrigation (NAI) systems perform in reducing AHTD during final irrigation protocols, based exclusively on studies whose analyses used microCT scanning. A systematic search of the studies published up to April 2020 was performed using MeSH terms and free terms, in the following databases: PubMed, Scopus, Web of Science, BVS (Lilacs and BBO) and Embase. The inclusion criteria consisted of laboratory studies that evaluated the amount of AHTD, and compared PUI with NAI protocols using microCT analysis. The risk of bias in the selected studies was assessed critically by two reviewers. A meta-analysis was performed using the RevMan software program (P<0.05), and included studies providing the standardized mean difference (SMD), using a fixed effect model, and adopting a confidence interval of 95%. In all, 3495 studies were identified, three of which met the inclusion criteria. All three were considered as having a low risk of bias. The meta-analysis comparing the ability of PUI and NAI protocols to remove hard tissue debris showed a higher percentage of AHTD reduction (P<0.01) for PUI, with a confidence interval of 1.41 [0.79, 2.02]. The heterogeneity among the studies was 82% (I2). Considering the limitations of the present study, this systematic review and meta-analysis showed that PUI was more effective than NAI in removing hard tissue debris, based exclusively on studies that used microCT scanning to provide a more precise analysis of the two techniques used. The findings presented in the present study reinforce the concept that PUI can increase residue removal and improve the cleanliness of the root canal in endodontic treatments.

Ten years of minimally invasive access cavities in Endodontics: a bibliometric analysis of the 25 most-cited studies

Objectives

This study aimed to analyze the main features of the 25 most-cited articles in minimally invasive access cavities.

Materials and Methods

An electronic search was conducted on the Clarivate Analytics' Web of Science ‘All Databases’ to identify the most-cited articles related to this topic. Citation counts were cross-matched with data from Elsevier's Scopus and Google Scholar. Information about authors, contributing institutions and countries, year and journal of publication, study design and topic, access cavity, and keywords were analyzed.

Results

The top 25 most-cited articles received a total of 572 (Web of Science), 1,160 (Google Scholar) and 631 (Scopus) citations. It was observed a positive significant association between the number of citations and age of publication (r = 0.6907, p < 0.0001); however, there was no significant association regarding citation density and age of publication (r = −0.2631, p = 0.2038). The Journal of Endodontics made the highest contribution (n = 15, 60%). The United States had the largest number of publications (n = 7) followed by Brazil (n = 4), with the most contributions from the University of Tennessee and Grande Rio University (n = 3), respectively. The highest number of most-cited articles were ex vivo studies (n = 16), and ‘fracture resistance’ was the major topic studied (n = 10).

Conclusions

This study revealed a growing interest for researchers in the field of minimally invasive access cavities. Future trends are focused on the expansion of collaborative networks and the conduction of laboratory studies on under-investigated parameters.

The shaping ability of WaveOne Gold, TRUShape and XP-endo Shaper systems in oval-shaped distal canals of mandibular molars: A microcomputed tomographic analysis

AIM

To compare the shaping ability of a heat-treated centric reciprocating file system (WaveOne Gold), a heat-treated eccentric rotary multifile system (TRUShape 3D Conforming Files), and a heat-treated expandable one-file rotary system (XP-endo Shaper) extending its activation time, in preparing oval-shaped root canals in extracted mandibular molars by means of microcomputed tomography (micro-CT) analysis.

METHODOLOGY

Thirty moderately curved oval-shaped distal roots of mandibular molars were selected. The normality of canal length, curvature angle, volume, surface area, structure model index, and aspect ratio were confirmed. The samples were randomly divided into three groups (n = 10). Micro-CT scans were taken before and after canals were instrumented using WaveOne Gold (size 35, .06 taper), or TRUShape (size 30, .06v taper), both following the manufacturer's instructions, or XP-endo Shaper following a new protocol with extended activation time. The mechanical preparation time for each sample was recorded. Pre- and postoperative images were analysed for the percentage of unprepared canal areas and the percentage of removed dentine. Data were compared between groups using the statistical analyses one-way ANOVA and Tukey tests (p < .05).

RESULTS

The percentage of unprepared canal areas was significantly higher with WaveOne Gold (% 11.5 ± 4.0) and TRUShape (% 12.4 ± 5.8) compared with XP-endo Shaper (% 5.2 ± 2.6) (p < .05). XP-endo Shaper removed significantly more dentine (3.3 ± 1.5 mm³ ) than WaveOne Gold (1.8 ± 0.8 mm³ ) and TRUShape (1.9 ± 0.8 mm³ ) (p < .05). No significant differences were seen for mechanical preparation time between WaveOne Gold (79 ± 31 s), TRUShape (104 ± 41 s) and XP-endo Shaper (71 ± 23 s) (p > .05).

CONCLUSIONS

The comparison of three recognized root canal filing systems has shown that with similar preparation times, the XP-endo Shaper removed more dentine (mm³ ) leaving less unprepared canal wall area (%) than WaveOne Gold and TRUShape when preparing oval-shaped root canals of extracted mandibular molars.

Antibacterial Efficacy of Triple Antibiotic Medication With Macrogol (3Mix-MP), Traditional Triple Antibiotic Paste, Calcium Hydroxide, and Ethanol Extract of Propolis: An Intratubular Dentin Ex Vivo Confocal Laser Scanning Microscopic Study

INTRODUCTION

This study aimed to assess the effectiveness of antibacterial activity of medications used in regenerative endodontic treatment.

METHODS

Sixty-seven dentin cylinders of single-rooted teeth were contaminated with a culture of Enterococcus faecalis (ATCC 29212; American Type Culture Collection, Manassas, VA) for 5 days. Samples were divided into 1 control group and the following experimental groups according to the medication applied: traditional triple antibiotic paste (TAP), clindamycin-modified TAP (mTAP), triple antibiotic medication with macrogol (3Mix-MP), clindamycin-modified 3Mix-MP (m3Mix-MP), calcium hydroxide (CH), and ethanol extract of propolis (EEP). After 14 days, the medications were removed, and the samples were submitted to confocal laser scanning microscopic analysis to quantify the percentage of viable bacteria. The distribution of data was confirmed by the Shapiro-Wilk test. The Kruskal-Wallis and Dunn tests were used for intergroup comparisons, and the Wilcoxon test was used for comparison between superficial and deep antibacterial efficacy for the same medication. The level of significance was set at P < .05.

RESULTS

3Mix-MP and m3Mix-MP presented significantly higher antibacterial efficacy compared with the other tested medications (P < .05), except for mTAP. mTAP was more effective than TAP (P < .05). The antibacterial efficacy of EEP and CH did not differ significantly from TAP and mTAP (P > .05). All medications showed effective antibacterial action compared with the control group (P < .05).

CONCLUSIONS

3Mix-MP and m3Mix-MP, which present extremely high concentrations of antibiotics (1500 mg/mL), were not more effective than mTAP at the concentration recommended by the American Association of Endodontists (5 mg/mL). Moreover, CH and EEP were as effective as TAP and mTAP.

Influence of variations in the environmental pH on the solubility and water sorption of a calcium silicate-based root canal sealer

AIM

To evaluate the influence of pH variation on the solubility and water sorption of a premixed calcium silicate-based root canal sealer (EndoSequence BC Sealer) compared to the gold standard based on epoxy resin (AH Plus Jet) after immersion in distilled water and phosphate-buffered saline (PBS).

METHODOLOGY

Solubility and water sorption were evaluated after immersion in distilled water or PBS at several pHs (5, 7 and 12) and the values were calculated as percentages of the original mass after 24 h, 7 and 30 days of immersion. The crystalline structures present in the sealers and surface precipitates were assessed by X-ray diffraction. The Shapiro-Wilk's test revealed that data were normally distributed; thus, statistical analysis was performed using one-way anova and Tukey's tests or independent t-test, assuming a 5% α-error.

RESULTS

EndoSequence BC Sealer was associated with significantly greater water sorption and solubility compared to AH Plus Jet in all tested conditions (P < 0.05). The acid environment increased the 24 h solubility of EndoSequence BC Sealer immersed in PBS (P < 0.05) and did not induce significative changes in the water sorption (P > 0.05). Alkaline pH reduced the solubility of EndoSequence BC Sealer and increased that of AH Plus Jet at all experimental times and soaking media (P < 0.05). Alkaline environment also significantly increased the water sorption of AH Plus Jet immersed in PBS (P < 0.05). Immersion in PBS significantly reduced the solubility of EndoSequence BC Sealer and significantly increased that of AH Plus Jet (P < 0.05). Precipitates on the surface of EndoSequence BC Sealer corresponding to hydroxyapatite and calcium carbonate were detected after immersion in PBS at pH 5 and 7 for 30 days.

CONCLUSIONS

EndoSequence BC Sealer had significantly greater solubility and water sorption than AH Plus Jet. Although the alkaline pH and soaking media directly influenced the solubility and water sorption of the sealers, the solubility of AH Plus Jet remained within the limits recommended by ISO 6876, whilst the solubility of the EndoSequence BC Sealer did not comply with ISO recommendations in all the conditions tested.

Antibacterial, biological, and physicochemical properties of root canal sealers containing chlorhexidine-hexametaphosphate nanoparticles

OBJECTIVE

The aim of this study was to evaluate the influence of the incorporation of chlorhexidine-hexametaphosphate nanoparticles (CHX-HMP NPs) on antibacterial, cytotoxic and physicochemical properties of AH Plus (AH), MTA Fillapex (MTA) and Pulp Canal Sealer (PCS).

METHODS

The NPs were synthesized and characterized by Scanning Electron Microscopy (SEM), Dynamic Light Scattering (DLS), zeta potential, Atomic Force Microscopy (AFM) and Energy-Dispersive X-ray Spectroscopy (EDS). The incorporation was made by weight, 2% and 5% of NPs. The antimicrobial activity, cytotoxicity, flow, radiopacity, setting time, solubility and pH were evaluated. The statistical analysis was performed by two-way analysis of variance test and Tukey post hoc test (P < 0.05).

RESULTS

SEM analysis showed the tendency for CHX-HMP NPs to cluster, the effective mean diameter measured by DLS: 169.39 nm and the zeta potential: -10.18 mV. The NPs were individually measured by AFM: 22.99-52.75 nm. EDS analysis identified the presence of C, N, O, Na, P, Cl. After incorporation: The Direct Contact Test showed an increase in the antimicrobial action of AH, PCS and MTA; the sealers showed a decrease in flow and at 24 h of immersion also an increase in solubility, but did not affect the radiopacity of the samples; AH setting time increased and MTA did not reach setting under any of the conditions tested. All samples showed a decrease in pH value as the immersion time progressed.

SIGNIFICANCE

The incorporation of NPs can improve the antimicrobial performance of endodontic sealers without impairing other biological and physicochemical properties.

Shaping ability and apical debris extrusion after root canal preparation with rotary or reciprocating instruments: a micro-CT study

Objectives

The aim of this study was to evaluate the shaping ability of the TruShape and Reciproc Blue systems and the apical extrusion of debris after root canal instrumentation. The ProTaper Universal system was used as a reference for comparison.

Materials and Methods

Thirty-three mandibular premolars with a single canal were scanned using micro-computed tomography and were matched into 3 groups (n = 11) according to the instrumentation system: TruShape, Reciproc Blue and ProTaper Universal. The teeth were accessed and mounted in an apparatus with agarose gel, which simulated apical resistance provided by the periapical tissue and enabled the collection of apically extruded debris. During root canal preparation, 2.5% sodium hypochlorite was used as an irrigant. The samples were scanned again after instrumentation. The percentage of unprepared area, removed dentin, and volume of apically extruded debris were analyzed. The data were analyzed using 1-way analysis of variance and the Tukey test for multiple comparisons at a 5% significance level.

Results

No significant differences in the percentage of unprepared area were observed among the systems (p > 0.05). ProTaper Universal presented a higher percentage of dentin removal than the TruShape and Reciproc Blue systems (p < 0.05). The systems produced similar volumes of apically extruded debris (p > 0.05).

Conclusions

All systems caused apically extruded debris, without any significant differences among them. TruShape, Reciproc Blue, and ProTaper Universal presented similar percentages of unprepared area after root canal instrumentation; however, ProTaper Universal was associated with higher dentin removal than the other systems.

Mouthguard use and attitudes regarding dental trauma among elite cross-country mountain biking and field hockey athletes

BACKGROUND/AIMS

Cross-country mountain biking and field hockey are two Olympic sports that pose a potential risk for dentofacial trauma. However, mouthguard use is not mandatory in either of these sports and knowledge about tooth rescue among athletes is often neglected. The aim of this cross-sectional epidemiological survey was to evaluate the prevalence of sports-related dentofacial injuries, mouthguard use, and attitudes regarding tooth rescue among cross-country mountain biking and field hockey athletes participating at pre-Olympic competitions held in Rio de Janeiro, Brazil.

MATERIALS AND METHODS

A convenience sample of 217 athletes from 33 countries participating in cross-country mountain biking (n = 82; mean age = 30.96 ± 8.52 years) and field hockey (n = 135; mean age = 19.72 ± 2.46 years) pre-Olympic competitions were examined clinically, and they answered a questionnaire regarding previous history of sports-related dentofacial injuries, attitudes toward mouthguard use, and tooth rescue.

RESULTS

There were 120 (55.30%) males and 97 (44.70%) females who participated in the study. The prevalence of facial trauma was higher in mountain biking (54.88%) than in field hockey (26.66%, P < .001). Fracture was the most prevalent facial injury in mountain biking (80%), while laceration was the most prevalent in field hockey (30.55%). Extensive dental injuries occurred more often in mountain biking (47.37%) than in hockey (12.50%). The teeth most often affected were the maxillary central incisors in both mountain biking (57.89%) and field hockey (93.75%). Mouthguard use was more frequent among field hockey athletes (41.48%) than in mountain biking (1.22%, P < .001). The overall knowledge about tooth rescue was low, and most of the athletes in both sports did not know what to do in case of an avulsed tooth.

CONCLUSIONS

Prevalence of dentofacial injuries among XCO-MTB and field hockey athletes participating at this pre-Olympic event was high. The majority of the athletes in this study did not use mouthguards and were unaware of recommendations in the case of an avulsed tooth.

Antibacterial efficacy and discolouration potential of antibiotic pastes with macrogol for regenerative endodontic therapy

This study aimed to evaluate the antibacterial efficacy and discolouration potential of antibiotic pastes containing macrogol. Seventy single-rooted teeth were contaminated with a culture of Enterococcus faecalis for 30 days. Double (DAP) and triple antibiotic pastes (TAP) containing propylene glycol or macrogol as vehicles were applied. After 15 days, bacterial viability was compared. Change in teeth coronal colour was measured by a spectrophotometer. Statistical analysis was performed using anova and Tukey's test (P < 0.05). TAP containing clindamycin and propylene glycol was the only medicament that led to the presence of contamination, while the same combination of antibiotics containing macrogol did not result in bacterial growth (P < 0.05). Only the pastes containing minocycline in formulation resulted in coronal discolouration (P < 0.05). Both DAPs evaluated and the TAP containing clindamycin and macrogol showed to be the preferable options for regenerative endodontic therapy, as they were effective against E. faecalis biofilm and did not promote tooth discolouration.

Efeito do consumo de álcool no desenvolvimento de lesão periapical induzida em ratos: uma análise microtomográfica

Objetivo: O objetivo deste estudo foi avaliar a influência do consumo crônico de álcool no aumento da destruição óssea periapical em ratos. Material e métodos: Foram selecionados 12 ratos machos da linhagem Wistar, aleatoriamente divididos nos grupos controle e álcool (n=6). Os ratos do grupo álcool foram submetidos à auto-administração de solução alcoólica contendo 25% de álcool puro. O grupo controle recebeu apenas água filtrada durante o estudo. Após as 5 semanas de adaptação do grupo álcool, todos os ratos foram anestesiados e a polpa dos seus primeiros molares inferiores esquerdos foi exposta à cavidade oral para indução da lesão periapical. Após 28 dias de exposição pulpar, os ratos foram sacrificados por sobredose de anestesia, e suas mandíbulas foram removidas e seccionadas para avaliação microtomográfica. As hemimandíbulas esquerdas foram fixadas e escaneadas no microtomógrafo SkyScan 1173 (Bruker, Kontich, Belgium). O tamanho da lesão periradicular foi medido a partir das imagens de microtomografia computadorizada (micro-CT), onde foram calculados a área de superfície e o volume da lesão. Também foram avaliadas a taxa percentual de ganho de peso e a ingestão de sólidos/líquidos dos grupos. Os dados foram estatisticamente analisados utilizando o teste t de Student (p<0,05). Resultados: Os animais do grupo controle tiveram uma maior taxa percentual de ganho de peso corporal e de ingestão tanto de sólidos como de líquidos (p<0,05). As lesões periapicais apresentaram maior volume e maior área nos animais do grupo álcool, em comparação ao grupo controle (p<0,05). Conclusão: O consumo crônico de álcool contribuiu para o aumento da destruição óssea periapical em casos de periodontite apical.

Effects of alcohol and nicotine consumption on the development of apical periodontitis in rats: a correlative micro-computed tomographic, histological and immunohistochemical study

AIM

To evaluate the effects of alcohol and nicotine, when used alone or simultaneously, in the development of apical periodontitis induced in rats, using a correlative analytic approach with micro-CT, histological and immunohistochemical analysis.

METHODOLOGY

Twenty-eight male Wistar rats were arranged into four groups: Control, Nicotine, Alcohol and Alcohol + Nicotine. The alcohol groups were exposed to self-administration of a 25% alcohol solution, whilst the other groups drunk only filtered water. The nicotine groups received daily intraperitoneal injections of a solution with 0.19 μL of nicotine per mL, whilst the other groups received saline solution. The pulps of the left mandibular first molars were exposed for 28 days to induce periapical lesions. Throughout the experiment, drug administration was maintained, and the animals had their weight and solid and liquid consumption measured. After euthanasia, the mandibles were removed and the area, volume and major diameter of the periapical lesions were measured using micro-computed tomography images. The samples were submitted to histopathological evaluation and immunohistochemistry for RANKL and PTHrP. Statistical analysis was undertaken with a significance level of 5%. Nonparametric data were analysed using the Kruskal-Wallis test followed by Dunn's test, whilst one-way anova followed by Tukey's test was performed for parametric data.

RESULTS

The alcohol groups had lower solid and liquid consumption and gained less weight when compared to the nonalcohol groups (P < 0.05). The Alcohol + Nicotine group had lesions with significantly larger volume and area when compared to the other groups (P < 0.05), whilst the Alcohol or Nicotine groups had significantly larger lesions than the control group (P < 0.05). There was no significant difference in the largest diameter of the lesions amongst groups (P > 0.05). The experimental groups had greater inflammatory response scores than the control group (P < 0.05), and the representative samples had more pronounced immunoreaction against RANKL and PTHrP antibodies.

CONCLUSIONS

Alcohol and nicotine consumption exacerbated the inflammatory response and the development of periradicular lesions in rats. The association of both substances enhanced their harmful effects.

Does tobacco smoking predispose to apical periodontitis and endodontic treatment need? A systematic review and meta-analysis

BACKGROUND

Controversial findings exist in the literature regarding the association between tobacco smoking and development of apical periodontitis or need for root canal treatment, with some studies reporting an increase in the prevalence of these outcomes in smokers, whilst others reporting no association.

AIM

To evaluate if there is scientific evidence to support an association between tobacco smoking and a greater prevalence of apical periodontitis and/or root canal treatments.

DATA SOURCES

A systematic search was performed using MeSH terms and free terms in the PubMed, Scopus, Virtual Health Library (VHL), Cochrane library and Open Gray databases.

STUDY ELIGIBILITY CRITERIA, PARTICIPANTS AND INTERVENTIONS

Observational studies that evaluated the association between smoking and the development or healing of periapical lesion and/or the prevalence of root canal treatment in humans were included.

STUDY APPRAISAL AND SYNTHESIS METHODS

A quality assessment of included studies was performed, and the relevant information and findings were evaluated. A meta-analysis using nine included studies was performed through RevMan software, and the certainty of evidence was evaluated through GRADE.

RESULTS

Fifteen studies were included, of which 10 were classified as low risk of bias, 4 were considered as moderate risk of bias and 1 as high risk of bias. Ten studies reported that smoking was associated with a greater prevalence of periapical periodontitis and/or root canal treatment. Five studies reported no association. Nine studies were included in the pooled meta-analysis, comprising two subgroups: apical periodontitis and root canal treatment. From these nine studies, eight studies were included in the apical periodontitis subgroup meta-analysis and demonstrated that this condition was significantly more prevalent in smokers when compared to the nonsmokers (odds ratio = 2.78[CI: 1.60, 4.85], P < 0.001; I²  = 79%; no adjusted odds ratio). Three studies were included in the root canal treatment subgroup meta-analysis and demonstrated an increased prevalence in smokers when compared to the nonsmokers (odds ratio = 2.73 [CI: 1.06, 2.83], P < 0.001; I²  = 72%; no adjusted odds ratio). The pooled meta-analysis demonstrated that smokers had twice the chance of having apical periodontitis and/or root canal treatment when compared to nonsmokers (odds ratio of 2.42 [CI: 1.59, 3.68], P < 0.01; I²  = 85%). The GRADE analysis demonstrated moderate certainty of evidence.

LIMITATIONS

Several confounding factors were identified such as misinformation regarding the period of time subjects had smoked, as well as the frequency of smoking and the number of cigarettes consumed. No adjustment in odds ratio data for confounding was performed.

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

This systematic review and meta-analysis indicate that tobacco smokers have an increased prevalence of periapical periodontitis and root canal treatments with moderate certainty of evidence.

Antimicrobial effectiveness of grape seed extract against Enterococcus faecalis biofilm: A Confocal Laser Scanning Microscopy analysis

This study evaluated the antimicrobial effectiveness of 6.5% Vitis vinifera grape seed extract (GSE) against Enterococcus faecalis biofilm using confocal laser scanning microscopy (CLSM). Saline solution (SS), 5.25% sodium hypochlorite (NaOCl) and 2% chlorhexidine (CHX) were used for comparison. Dentin discs were inoculated with E. faecalis strain establishing a 3-week-old biofilm. Discs (n = 10) were exposed to 5.25% NaOCl, 2% CHX, 6.5% GSE and SS (negative control) for 10 min. Discs were stained with the fluorescent LIVE/DEAD-BacLight™ dye and analysed using CLSM. The proportion of dead cells in biofilm was analysed using one-way anova and Tukey tests (P < 0.05). A higher proportion of dead cells was found in GSE group compared with CHX and SS (P < 0.05). NaOCl group was associated with the highest proportion of dead cells (P < 0.05). GSE presented antimicrobial activity against E. faecalis; however, NaOCl was the most effective irrigant solution. GSE was more effective than CHX and SS.

Biopure MTAD Induces DNA Damage but Not Cellular Death: An In Vitro Study

Objectives: The purpose of this study was to evaluate the capacity of BioPure MTAD to induce genetic damage in vitro. Genotoxicity was assessed by the single cell gel (comet) assay.

Methods: Chinese hamster ovary (CHO) cells or murine fibroblasts cells were exposed to increasing final concentrations ranging from 0.1 a 10%. All treatments were performed for 1 hour at 37°C. The negative control group was treated with vehicle control (phosphate buffer solution - PBS) for 1 hour at 37°C and the positive control group was treated with methylmetanesulfonate (at 1 µM) for 1 hour at 37°C.

Results: Present results showed that the BioPure MTAD was able to promote DNA breakage in CHO cells only at the highest concentration tested as well as to induce significant increase in tail moment at all tested concentrations in murine fibroblasts.

Conclusions: In summary, our results indicate that BioPure MTAD is a genotoxic agent as depicted by the single cell gel (comet) assay. (Eur J Dent 2009;3:285-289)

Improved sealing ability promoted by calcium silicate-based root canal sealers

Aim: This study investigated the sealing ability produced by AH Plus (Dentsply DeTrey, Konstaz, Germany), EndoSequence BC sealer (Brasseler USA, Savannah, GA, USA), GuttaFlow (Coltène/Whaledent, Altstätten, France) and MTA Fillapex (Angelus, Londrina, Brazil). Methdos: A total of forty-six single-root human canines were prepared and randomly divided into four experimental groups (n=10): MTA Fillapex, EndoSequence BC Sealer, AH Plus or GuttaFlow. Teeth with intact crowns served as negative controls (n=3) and teeth filled with only gutta-percha served as positive controls (n=3). Teeth were mounted in a two-chamber apparatus and exposed to Enterococcus faecalis. The number of days over a 60-days period was recorded for the appearance of turbidity in the lower chamber. Kaplan-Meier method was used to estimate the survival curves. The nonparametric log-rank test was used to compare the survival curves using a significance level of 0.05. Results: The results at the end of the observation time were further analyzed by chi-square testing. All positive controls leaked within 24 h, whereas none of the negative controls leaked after 60 days. EndoSequence BC Sealer and MTA Fillapex had significant less bacterial leakage (P<0.05) than the other tested sealers. No significant difference between AH Plus and GuttaFlow was observed (P>0.05). Conclusion: In conclusion, calcium-silicate based root canal sealers promoted improved sealing ability when compared to other endodontic sealers.

Bond Strength of Experimental Root Canal Sealers Based on MTA and Butyl Ethylene Glycol Disalicylate

Abstract This study investigated the bond strength of two experimental root canal sealers based on MTA and butyl ethylene glycol disalicylate: MTAe and MTAe-HA. The reference materials used for comparison were AH Plus and MTA Fillapex. Twenty human upper incisors were selected and one 1 mm slice was obtained from the cervical third of each root. On the coronal surface of each slice, four 0.9 mm wide holes were drilled through the dentine. Standardized irrigation was performed and holes were filled with one of the four tested sealers: AH Plus, MTA Fillapex, MTAe, and MTAe-HA. The filled slices were stored in a PBS solution (pH 7.2) for 7 days at 37 °C. A push-out assessment was performed with a 0.7 mm plunger tip. Load was applied at a crosshead speed of 0.5 mm/min until sealer displacement. The results were expressed in MPa. The Kruskal-Wallis test was applied to assess the effect of each sealer on the push-out bond strength. Mann-Whitney with Bonferroni correction was used to isolate the differences. The alpha-type error was set at 0.05. Significant differences among medians values obtained by materials were observed (p<0.001). AH Plus displayed the highest value of bond strength (p<0.001). In contrast, MTA Fillapex presented the lowest bond strength among all tested sealers (p<0.001). Experimental sealers showed intermediary bond strength values, with no statistical differences between them (p>0.05). In conclusion, experimental root canal sealers presented suitable bond strength outcomes when compared to MTA Fillapex.

Novos Cimentos Reparadores em Endodontia: uma Revisão De Literatura

O presente estudo teve por objetivo realizar uma Revisão de Literatura acerca dos materiais reparadores disponíveis no mercado indicados para o tratamento de perfurações, obturações retrógradas em cirurgias paraendodônticas, apicificações e apicigenêses,    e mais recentemente em tampões cervicais em revascularizações sendo algumas das principais características esperadas desses materiais biocompatibilidade, bioatividade e boa capacidade seladora. Para isto, realizou-se uma busca no banco de dados MEDLINE, no período de 2011 a 2017, em língua inglesa, pesquisando os descritores: “Root repair material”, “Root end-filling”, “cytotoxicity”, “biocompatibility”, “bioactivity” e “sealing”. Foram encontrados 61 artigos e selecionados 42, sendo utilizados como critérios de inclusão trabalhos clínicos e laboratoriais in vivo e in vitro. Na maioria dos trabalhos, cimentos reparadores como ProRoot MTA, MTA-Angelus, Endosequence Root Repair Material, Biodentine e Bioaggregate apresentaram biocompatibilidade semelhante, oferecendo menor citotoxicidade quando comparados com outros cimentos disponíveis no mercado. Quanto à bioatividade, os materiais apresentam resultados muito próximos. A maioria dos trabalhos confirmou a maior capacidade seladora de cimentos à base de MTA e silicato tricálcico, sendo o Biodentine o que apresentou os melhores resultados. Diante do exposto fica evidente a qualidade e similaridade dos materiais, cabendo ao cirurgião-dentista a opção pelo material com o qual melhor adaptar-se.Palavras-chave: Endodontia. Reabsorção Radicular. Doença Iatrogênica.

Avaliação comparativa da eficácia de um sistema alternativo de remoção de guta-percha com ou sem solvente

Objetivo: avaliar a eficácia do Sistema Reciproc, com ou sem solvente, para remoção do enchimento endodôntico de canais radiculares ovais. O tempo necessário para a remoção da guta-percha e a fratura do instrumento também foram avaliados. Material e Métodos: quarenta pré-molares unirradiculares retos foram confeccionados até o tamanho 30 e preenchidos com guta-percha e cimento, sendo aleatoriamente divididos em dois grupos de retratamento (n = 20), tratados com Sistema Reciproc com ou sem clorofórmio (RS + C e RS). Para todas as raízes, foram registrados erros de procedimento, tempo de retratamento e material apicalmente extrusado. Após o retratamento, as raízes foram divididas longitudinalmente e depois fotografadas. Todas as imagens foram avaliadas com o software Image Tool para calcular a porcentagem de material residual. Os testes de Kolmogorov Smirnov e t foram usados ??para determinar diferenças significativas em P <0,05. Resultados: nenhum tratamento removeu completamente o material obturador da raiz dos canais radiculares. A análise da área total não revelou diferenças estatísticas entre os dois grupos (P> 0,05). Ambos os grupos também mostraram resultados semelhantes em todos os terços testados, sem diferenças estatísticas (P> 0,05). O RS sem solvente foi mais rápido no preenchimento da remoção do material que o RS + C (P <0,05). Para ambos os grupos, nenhum dos instrumentos mostrou fratura intracanal ou sinais visíveis de deformação plástica. Conclusão: em conjunto, nossos resultados demonstraram que o Sistema Reciproc utilizado sem solvente exigiu menos tempo para remover a mesma quantidade de material de preenchimento de raízes do que o Sistema Reciproc com solvente. No entanto, independentemente do uso de solvente, a mesma qualidade de limpeza foi obtida.

Bending Resistance and Cyclic Fatigue Life of a new Single-File Reciprocating Instrument Waveone Gold

Objective:

The present study aimed to evaluate the bending resistance and cyclic fatigue fracture resistance of a new single-file reciprocating instrument called WaveOne Gold. Reciproc and WaveOne instruments were used as references for comparison.

Methods:

Sixty 25-mm NiTi instruments (Reciproc R25, WaveOne Primary and WaveOne Gold Primary) were tested. Flexibility was determined by applying 45° bending tests using a universal testing machine (n=10). A custom-made device was used during cyclic fatigue test (n=10), comprising a stainless steel artificial canal measuring 1.4 mm in diameter, 19 mm in total length with an 86° angle and 6 mm radius of curvature. Possible deformations at the helical shaft and mode of fracture were evaluated using scanning electron microscopy analysis. Statistical analysis was performed using one-way analysis of variance. Post hoc pair-wise comparisons were performed using Tukey’s test for multiple comparisons (P<0.05).

Results:

WaveOne presented significantly higher bending resistance than the other tested systems (P<0.05), whereas Reciproc presented the lowest bending resistance (P<0.05). Reciproc revealed a significantly longer cyclic fatigue fracture resistance than the other systems (P<0.05).

Conclusion:

Although WaveOne Gold presented higher flexibility than WaveOne, no differences in the resistance to fatigue were observed between both systems. The Reciproc files were more flexible and resistant to fatigue for the angle of curvature of 86° and 6 mm radius than WaveOne and WaveOne Gold files.

In vitro genotoxicity and cytotoxicity in murine fibroblasts exposed to EDTA, NaOCl, MTAD and citric acid

The aim of the present study was to evaluate the capacity of some root canal irrigants to induce genetic damage and/or cellular death in vitro. Murine fibroblast cells were exposed to ethylenediaminetetraacetic acid (EDTA), sodium hypochlorite (NaOCl), MTAD™ and citric acid in increasing concentrations for 3 h at 37ºC. The negative control group was treated with vehicle control (phosphate buffer solution - PBS) for 3 h at 37°C, and the positive control group was treated with methylmetanesulfonate, 1 μM. for 3 h at 37°C. Cytotoxicity was assessed by the trypan blue test and genotoxicity was evaluated by the single cell gel (comet) assay. The results showed that exposure to 2.5% and 5% NaOCl and 8.5% citric acid resulted in a significant cytotoxic effect. NaOCl, EDTA and citric acid did not produce genotoxic effects with respect to the comet assay data for all evaluated concentrations. Although MTAD was not a cytotoxic agent, it showed significant genotoxic effects at all tested concentrations (ANOVA and Tukey's test; p<0.05). NaOCl, EDTA and citric acid were found to be cytotoxic in a dose-dependent manner, but they were not genotoxic. MTAD did not cause cell death, but presented genotoxic effects.

Clinical management of a complicated crown-root fracture: a case report

This report describes the clinical procedures involved in the treatment of a complicated crown-root fracture in the maxillary left central incisor with a wide open apex of a 10-year-old male patient, due to fall from his own height. Post-trauma treatment comprised cervical pulpotomy and adhesive tooth fragment reattachment. After 1 year, clinical and radiograph examinations showed pulp necrosis and an associated periapical lesion. Endodontic therapy with calcium hydroxide-base intracanal dressing, root canal filling and orthodontic extrusion were performed. Extrusion was completed within approximately 16 weeks and the tooth was restored with a post-core system and a prosthetic crown. After a 3 years of follow-up, there was no evidence of apical periodontitis and the tooth was satisfactory both esthetically and functionally.

Biopure MTAD Induces DNA Damage but Not Cellular Death: An In Vitro Study

OBJECTIVES

The purpose of this study was to evaluate the capacity of BioPure MTAD to induce genetic damage in vitro. Genotoxicity was assessed by the single cell gel (comet) assay.

METHODS

Chinese hamster ovary (CHO) cells or murine fibroblasts cells were exposed to increasing final concentrations ranging from 0.1 a 10%. All treatments were performed for 1 hour at 37 degrees C. The negative control group was treated with vehicle control (phosphate buffer solution - PBS) for 1 hour at 37 degrees C and the positive control group was treated with methylmetanesulfonate (at 1 muM) for 1 hour at 37 degrees C.

RESULTS

Present results showed that the BioPure MTAD was able to promote DNA breakage in CHO cells only at the highest concentration tested as well as to induce significant increase in tail moment at all tested concentrations in murine fibroblasts.

CONCLUSIONS

In summary, our results indicate that BioPure MTAD is a genotoxic agent as depicted by the single cell gel (comet) assay. (Eur J Dent 2009;3:285-289).

Bacterial leakage in root canals filled with calcium hydroxide paste associated with different vehicles

This in vitro study evaluated, using a bacterial leakage model, whether intracanal medication with calcium hydroxide [Ca(OH)2]-based pastes prepared with different vehicles, has inhibitory effect on corono-apical leakage of bacteria. Forty instrumented human canines were dressed with Ca(OH)2 p.a. associated with: G1 = distilled water; G2 = polyethylene glycol (PG); G3 = PG + CMCP; and G4 = glycerin. Five teeth with intact crowns served as negative controls and 5 instrumented teeth without temporary dressing served as positive controls. All teeth were mounted in a 2-chamber apparatus and then exposed to human saliva for 63 days. Leakage was recorded when turbidity was observed in the lower chamber. Fifty percent of the samples of G1 and G2, 10% of G3 and 80% of G4 were fully contaminated after 9 weeks. Statistically significant differences were observed with paired comparisons G3 and G4 (p=0.0069), with G3 achieving better seal against bacterial leakage than G4.

Microbiological evaluation of primary endodontic infections in teeth with and without sinus tract

AIM

To examine the microbiological status of primary endodontic infections in teeth with and without a sinus tract.

METHODOLOGY

Samples were collected by means of a size 15 H-type file and two sterile paper points from 30 cases of primary endodontic infections with (n = 15) or without (n = 15) a sinus tract. The presence of 40 bacterial species was determined by the checkerboard DNA-DNA hybridization method.

RESULTS

The species found at the highest levels and prevalence were Fusobacterium nucleatum sp. vincentii, Porphyromonas gingivalis, Veillonella parvula, Enterococcus faecalis, Campylobacter gracilis and Neisseria mucosa. Total bacterial counts were similar between teeth with (44 x 10(5)) and without (50 x 10(5)) a sinus tract (t-test: P > 0.05). E. faecalis, Streptococcus anginosus, Capnocytophaga sputigena and Capnocytophaga gingivalis had significantly higher counts in the absence of sinus tract (Mann-Whitney test, P < 0.05). Higher levels of P. gingivalis and Fusobacterium nucleatum sp. nucleatum were observed in cases with a sinus tract. Leptotrichia buccalis (OR = 1.83; CI 95%) and Porphyromonas endodontalis (OR = 2.15; CI 95%) were associated with an increased chance of subjects having a sinus tract.

CONCLUSIONS

Primary endodontic infections were associated with a large variety of bacterial species. Specific differences between the composition of the microbiota of primary root canal infections were observed in cases with or without a sinus tract.

The influence of organic load on the antimicrobial activity of different concentrations of NaOCl and chlorhexidine in vitro

AIM

To evaluate bacterial growth after contact with sodium hypochlorite (NaOCl; 1 and 5%) and chlorhexidine (CHX; 0.12, 0.5 and 1%) in vitro with or without the addition of organic material (bovine serum albumin (BSA) 0.5%).

METHODOLOGY

Bacterial samples (American Type Culture Collection (ATCC)) of Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Porphyromonas gingivalis and Fusobacterium nucleatum were kept in contact with each irrigating solution for varying intervals of time: immediately (t0), 5 min (t5), 15 min (t15) and 30 min (t30). Each test was repeated 10 times. In half of the specimens, 0.5% BSA was added as organic material in an attempt to simulate the organic tissue present in the root canal system. Bacterial growth under appropriate condition of incubation was evaluated and compared for each microorganism at all time intervals.

RESULTS

A 0.12% CHX solution did not eliminate E. faecalis at any time interval. One percent CHX eliminated all strains, as did both NaOCl concentrations. BSA did not interfere substantially with the antimicrobial activity of any of the irrigating solutions.

CONCLUSIONS

Under the condition of this study, a 0.12% CHX solution was ineffective at killing E. faecalis.

Antimicrobial activity of different concentrations of NaOCl and chlorhexidine using a contact test

The purpose of this study was to analyze the in vitro antimicrobial activity of sodium hypochlorite (1% and 5%) and chlorhexidine (0.12%, 0.5% and 1%). Bacterial samples (ATCC) of Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Porphyromonas gingivalis and Fusobacterium nucleatum were submitted to a contact test. Solutions were evaluated at different time intervals: immediately, 5 min, 15 min, and 30 min after contact and repeated 10 times. The results of the contact test showed that 0.12% chlorhexidine did not eliminate E. faecalis at any time interval, while 0.5% and 1% chlorhexidine and 1% and 5% sodium hypochlorite did. These results permit us to conclude that to obtain better antimicrobial activity, chlorhexidine in a concentration greater than 0.12% should be used.