Effect of preemptive use of a nonsteroidal anti-inflammatory drug and a corticosteroid on the efficacy of inferior alveolar nerve blockade and postoperative pain control in endodontic treatment of molars with symptomatic pulpitis: A randomized double-blind placebo-controlled clinical trial.

AIM: The anaesthetic success rate of an inferior alveolar nerve block (IANB) in mandibular molars with irreversible symptomatic pulpitis can be low, and postoperative pain control in teeth with this diagnosis can be challenging. This study aimed to evaluate the influence of preemptive use of dexamethasone and oral potassium diclofenac on the success of IANB. The influence of these drugs on the intensity of postoperative pain was assessed as a secondary outcome. METHODOLOGY: Eighty-four patients with mandibular molars diagnosed with irreversible symptomatic pulpitis recorded preoperative pain intensity using a cold thermal test and a modified Numerical Rating Scale (mNRS). Sixty minutes before the anaesthetic procedure, patients were randomly assigned to one of three groups based on the medication they received: dexamethasone (4 mg), diclofenac potassium (50 mg), or placebo. All patients received IANB with 4% articaine (1:200 000 epinephrine), and 15 min later, they were evaluated for pain intensity using the cold thermal test. Anaesthetic success was analysed. The pain intensity was then recorded, and endodontic treatment and provisional restoration of the tooth were executed in a single session. Patients were monitored for 6, 12, 24, 48 and 72 h using the mNRS to assess the intensity of postoperative pain. RESULTS: There was a statistically significant increase in anaesthetic success when 4 mg dexamethasone (39.3%) or 50 mg diclofenac potassium (21.4%) was used compared to the placebo group (3.6%) (p < .001), with no significant difference between the two drugs. Regarding postoperative pain, dexamethasone was superior to placebo at 6 h (p < .001), with diclofenac having an intermediate behaviour, not differing between dexamethasone and placebo (p > .05). There was no significant difference amongst the groups at 12 h (p > .05). At 24, 48 and 72 h, the effectiveness of dexamethasone and diclofenac were comparable, and both were superior to placebo (p < .001). CONCLUSION: The use of dexamethasone or diclofenac potassium was favourable in terms of increasing the success rate of inferior alveolar nerve block in cases of mandibular molars with irreversible symptomatic pulpitis and decreased the occurrence of postoperative pain when compared to the use of a placebo.

Effect of supplementary sodium hypochlorite agitation techniques on an ex vivo oral multispecies biofilm during passive disinfection of simulated immature roots.

AIM: To compare the effect of different sodium hypochlorite (NaOCl) agitation techniques on an ex vivo oral multispecies biofilm during passive disinfection of simulated immature roots. METHODOLOGY: Extracted human teeth were prepared to simulate immature roots. They were infected with a dental plaque-derived multispecies biofilm and cultured for 14 days. The roots were randomly designated into four groups: (1) negative control (PBS), (2) 1.5% NaOCl (CNI), (3) CNI + Ultrasonic activation (UA), (4) CNI + EasyClean agitation (ECA), (5) CNI + XP-endo finisher agitation (XPF), and (6) positive control (6% NaOCl). Biofilm samples were collected from the root canals and used to determine the number of viable cells (colony-forming units), scanning electron microscopy, and 16S rRNA gene sequencing. The mean colony-forming units per mL (CFU/mL) were analysed using One-way anova. 16S rRNA sequencing data were analysed for alpha (observed OTUs, Shannon index, and Chao1) and beta diversity (Bray-Curtis dissimilarities). The LEfSe analysis was used to determine the effect of treatment procedures on the abundance of root canal microbiota. The significance was set at .05. RESULTS: PBS and CNI samples had significantly higher CFU/mL counts than UA, ECA, XPF, and 6% NaOCl samples (p < .05). The pre-treatment, PBS, and CNI groups had significantly greater alpha diversity than the UA, ECA, XPF, and 6% NaOCl groups (p < .05). NaOCl agitation groups and the 6% NaOCl group achieved a more pronounced reduction in bacteria from the genera Fusobacterium, Actinomyces, Porphyromonas, and Capnocytophaga. CONCLUSIONS: The effectiveness of passive disinfection protocols was enhanced by NaOCl agitation techniques, suggesting that this supplementary method can improve the outcome of revitalization procedures.

Epidemiological profile of luxations injuries with or without dental fractures in permanent teeth: A 10-years retrospective study.

BACKGROUND/AIM: This study assessed the epidemiology of luxation injuries with or without dental fractures in patients attending the outpatient clinic of a Brazilian dental school over the past decade. MATERIAL AND METHODS: We reviewed clinical records from a specialized center for dental trauma care in Brazil, focusing on patients who experienced at least one traumatic dental injury (TDI) in a permanent tooth between 2012 and 2022. The extracted data included sex, age, etiology, time between trauma occurrence and the search for initial care, TDI classification, and the need for endodontic treatment. The statistical analysis involved Pearson's chi-squared and Fisher's exact tests at a 5% significance level. RESULTS: The 366 analyzed clinical records included 166 patients (350 teeth) with luxation injuries. Men (n = 102) showed a higher prevalence of luxation injuries than women (n = 64). Extrusive luxation prevailed (n = 99 patients and 208 teeth). Patients with luxation injuries sought care promptly after dental trauma incidents (p = .02) and demonstrated a higher incidence of endodontic treatment (p < .0001) than those without luxation injuries. Lateral luxation was notably associated with traffic accidents (p < .0001). The combination of luxation injuries and tooth fractures did not correlate with a higher need for endodontic treatment (p > .05). CONCLUSIONS: Age and trauma etiology seemed to have influenced the epidemiological profile of luxation injuries. Additionally, these injuries affected the time to seek initial care and the need for endodontic treatment.

Impact of passive ultrasonic irrigation on the outcome of non-surgical root canal treatment: a systematic review and meta-analysis of randomized clinical trials.

OBJECTIVE: This systematic review aimed to assess the impact of Passive Ultrasonic Irrigation on the periapical healing rate of primary root canal treatment compared to conventional syringe irrigation. METHODS: Registered a priori in the PROSPERO database, this review was conducted by two independent reviewers who performed an electronic search up to December 2023. The search included databases such as MEDLINE (PubMed), Scopus, Web of Science, Embase, LILACS, and the Cochrane Library, as well as grey literature. We included randomized clinical trials (RCTs) that focused on patients undergoing primary root canal treatments. The study compared intervention groups using PUI with control groups that did not use activation techniques. Periapical healing was assessed over follow-up periods of at least six months, utilizing either periapical radiographs or cone-beam computed tomography. To synthesize the findings, a meta-analysis and trial sequence analysis were conducted, employing the Relative Risk as the measure of effect, with a 95% confidence interval. The GRADE approach was utilized to assess the certainty of the evidence. RESULTS: The meta-analysis incorporated three RCTs, involving 474 patients (501 teeth). The analysis revealed that PUI led to a higher rate of periapical healing compared to CSI (Relative Risk: 1.10; 95% Confidence Interval: 1.01-1.21, I² = 0%), with moderate certainty of evidence. CONCLUSIONS: Despite the limited number of high-quality RCTs, the findings showed a positive impact of PUI on periapical healing rates in primary root canal treatments, in comparison to CSI. REGISTER: CRD42021290894.

Microbiological profile of root canals indicated for endodontic retreatment due to secondary endodontic infections or for prosthetic reasons.

OBJECTIVE: The objective of this study was to evaluate the microbiological profile of root canals indicated for endodontic retreatment due to secondary endodontic infections evidenced by the presence of chronic apical periodontitis (G1) or for prosthetic reasons, without clinical and radiographic signs of endodontic reinfection (G2). METHODS: Microbiological samples were collected from thirty teeth (N=30) out of which 15 were indicated for retreatment due to the presence of chronic apical periodontitis (G1) and 15 were indicated exclusively for prosthetic reasons (G2). Samples were collected from root canals before (S1), after chemomechanical preparation (S2), and after 30 days of intracanal medication composed of calcium hydroxide and 2% chlorhexidine gel (S3). The molecular analysis was performed using Nested-PCR for the detection of 17 bacterial species. The efficacy of each stage of the retreatment in reducing the microbial load was verified by counting colony-forming units (CFU). The statistical analysis considered a significance level of 5%. RESULTS: The results showed that bacteria were detected in 100% of the cases in S1, in both groups, by Nested PCR. The most frequently found species in S1 in both groups were Enterococcus faecalis, Fusobacterium nucleatum, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, and Parvimonas micra. The microbial load of G1 was higher than G2 in the initial samples (S1). Endodontic retreatment was effective in reducing the microbial load in G1 and G2. Statistically significant associations were found between specific bacteria and clinical signs and symptoms. CONCLUSION: It was concluded that the microbial community present in the root canal of teeth indicated for endodontic retreatment is mixed and heterogeneous. G1 and G2 differ in the number of species per case and microbial load. CLINICAL RELEVANCE: Endodontic retreatment was effective in reducing the microbial load. Statistically significant associations were found between specific bacteria and clinical signs and symptoms.

Critical appraisal of confounding factors of observational studies on the association between dentofacial features and dental trauma in a Brazilian population.

AIMS/OBJECTIVES: Dental trauma is a highly prevalent dental emergency. Children and adolescents without inadequate lip coverage, increased overjet, and anterior open bite are associated with the occurrence of traumatic dental injuries. Observational studies do not allow the inference of causality, one of the reasons being: the potential confounding factors. Therefore, this review aimed to critically appraise the confounding factors considered in epidemiological studies that associate dentofacial features with the occurrence of dental trauma in Brazilian children and adolescents. METHODS: Studies included in the qualitative synthesis of a recently published comprehensive systematic review and meta-analysis on the topic were screened. Studies that only mentioned the performance of bivariate analyzes or that did not mention the performance of multivariate analyzes were excluded. Evaluation of control statements for possible confounders and bias consideration was performed for each selected study. Confounding factors in these studies were also identified and categorized according to their domains. RESULTS: Fifty-five observational studies were screened, of which 11 were excluded due to the mention of only bivariate analyzes or the lack of multivariate analyses. The remaining 44 studies were critically appraised. Of these, 9 studies specifically mentioned the term confounding, and 12 studies mentioned the term bias. However, only 14 studies mentioned limitations on confounding factors in their findings. Among the 99 different variables identified, the most used were type of trauma, followed by sex and age. CONCLUSION: Most studies did not acknowledge the control for possible confounding factors and rarely stressed the need for caution in interpreting their results. Cross-sectional studies do not allow inferring a cause-and-effect relationship between dentofacial features and dental trauma.

Comparative analysis of bacterial content, levels of lipopolysaccharides and lipoteichoic acid in symptomatic and asymptomatic endodontic infections at different stages of endodontic treatment.

OBJECTIVES: This study aimed to detect the presence of specific bacteria and to evaluate the levels of lipopolysaccharides (LPS) and lipoteichoic acid (LTA) in symptomatic necrotic root canals associated with acute apical abscess (symptomatic group - GI). It also aimed to compare the findings with those presented by asymptomatic necrotic root canals (asymptomatic group - GII) in the different stages of the endodontic treatment. MATERIALS AND METHODS: Microbiological samples were collected from 20 root canals, including purulent collection from acute apical abscesses, before and after chemo-mechanical preparation (CMP) preparation (CMP) with chlorhexidine gel 2% and after 30 days of intracanal medication (ICM) with (Ca[OH]2) + chlorhexidine. The culture method was used to evaluate the efficacy of CMP and ICM. Nested PCR was used to detect the presence of 17 specific bacteria. Levels of LPS were measured by using limulus amebocyte lysate, whereas enzyme-linked immunosorbent assay was used for the quantification of LTA. RESULTS: CMP was effective in reducing the microbial load in both groups (P < 0.05). LPS levels were higher in GI than in GII (P < 0.05). There was a significant reduction in the LPS levels after CMP and ICM (P < 0.05) in GI and GII. LTA levels were significantly reduced in GI after ICM and in GII after CMP and ICM (both P < 0.05). Fusobacterium nucleatum and Enterococcus faecalis were frequently identified in both groups, alone or in combination with each other. CONCLUSION: Different species were detected in all stages of the endodontic treatment. CMP was able to reduce bacterial content and the levels of LPS, but not of LTA in the symptomatic group. High levels of LPS were correlated with spontaneous pain and pain to percussion in the symptomatic group. CLINICAL RELEVANCE: This clinical study showed that chemo-mechanical preparation was able to reduce bacterial load and levels of LPS, but not of LTA in the symptomatic group. Elevated levels of LPS were correlated with the presence of symptomatology.

The association of inadequate lip coverage and malocclusion with dental trauma in Brazilian children and adolescents - A systematic review and meta-analysis.

BACKGROUND/AIM: Dental trauma (DT) occurs frequently in children and adolescents. Therefore, understanding the factors associated with its occurrence in these age groups is important to establish specific preventive measures. The aim of this study was to investigate the relationships of lip coverage, overjet, and open bite to dental trauma in Brazilian children and adolescents. MATERIAL AND METHODS: The review protocol was registered in the PROSPERO database (CRD42020156290) and the bibliographic search was performed in nine electronic databases until July 2020. The studies included were observational, performed in Brazil, with healthy children and adolescents (0-19 years old), and without the restriction of date or language. Two reviewers assessed the individual risk of bias of the eligible studies with a standardized checklist. The meta-analyses were stratified by dentition stage and age range using fixed or random effects, odds ratio (OR) as the effect measure, and 95% confidence interval. The heterogeneity across studies was assessed with the I² test and the GRADE approach assessed the certainty of evidence. RESULTS: The search presented 2493 initial results, from which 55 met the eligibility criteria and were included. Most studies (67%) presented a low risk of bias and were published between 2000 and 2019. Children and adolescents with inadequate lip coverage are 1.86-2.36 times more likely to suffer from DT, while those with increased overjet are 1.94-3.11 times more likely. Children with primary dentitions and anterior open bites are 1.76 (95% CI: 1.20-2.59) times more likely to suffer from DT. The certainty of evidence varied from very low to moderate. CONCLUSIONS: Inadequate lip coverage, increased overjet, and anterior open bite are associated with the occurrence of dental trauma in Brazilian children and adolescents.

The antimicrobial effect of different ozone protocols applied in severe curved canals contaminated with Enterococcus faecalis: ex vivo study.

The aim of this study was to evaluate 3 different irrigation protocols using ozone on monoculture biofilm of Enterococcus faecalis. Fifty disto-buccal roots of maxillary first molars were instrumented up to the size 25.08, sterilized and then incubated with Enterococcus faecalis for 21 days for biofilm maturation in the root canal walls. After contamination, the initial collection (S1) was performed and the 50 samples were divided in 3 experimental groups (n = 15) and 1 positive control group (n = 5) as follows: Group1: Ozonated water (40 µg/ml); Group2: gaseous ozone (40 µg/ml); Group3: Ozonated water (40 µg/ml) under continuous ultrasonic irrigation (CUI) and, Group 4: 2.5% sodium hypochlorite (positive control). The final collection (S2) was performed using hedstroem files # 25 by scraping the root canal wall and absorbed paper cone. The collected samples were analyzed by CFU/ml count and qPCR. To compare the effect of irrigation methods and to investigate E. faecalis count data, Kruskal-Wallis and Wilcoxon nonparametric tests were used at p < 05. The values of the differences between the S1 values and the S2 values revealed that the groups did not differ significantly for either E. faecalis CFU count data (p = 0.713) or q-PCR (p = 0.185), however, it is observed that for all groups, the CFU count of E. faecalis decreased over 99%. For the q-PCR assay, the reduction was on the order of 74-95%. Only the NaOCl positive control group presented total elimination of CFU/mL bacterial counting. The ozone protocols assessed were similar in regard to Enterococcus faecalis reduction.

Evaluation of the presence of microorganisms from root canal of teeth submitted to retreatment due to prosthetic reasons and without evidence of apical periodontitis.

AIM: The objective of this study was to evaluate the presence of microorganisms in the root canals (RC) of teeth submitted to endodontic retreatment due to prosthetic reasons and without evidence of apical periodontitis. MATERIAL AND METHODS: Twenty teeth referred to endodontic retreatment due to prosthetic reasons and without evidence of apical periodontitis were included in this study. Gutta-percha (GP) was collected from each third of the RC. After GP removal, microbial samples were also collected from the full extension of RC using paper points and files. The samples were cultivated in Fastidious Anaerobe Agar and the colony-forming units (CFU/mL) were counted. They were also semi-quantitatively analyzed by checkerboard DNA-DNA hybridization using 40 DNA bacterial probes. RESULTS: Microorganisms were found in all samples. The coronal third of GP was more contaminated than the apical third (p ≤ 0.05). There was prevalence of Enterococcus hirae and Enterococcus faecalis in all RC thirds and also in the samples collected from the full extension of RCs. CONCLUSION: Microorganisms were found in all cases referred to endodontic retreatment due to prosthetic reasons and without evidence of apical periodontitis. Enterococcus was the genus most frequently detected. CLINICAL SIGNIFICANCE: An endodontic retreatment should be considered before replacing a prosthesis.

Effectiveness of calcium hydroxide-based intracanal medication on infectious/inflammatory contents in teeth with post-treatment apical periodontitis.

OBJECTIVE: The objective of this work was to investigate in vivo the effects of calcium hydroxide-based intracanal medication (ICM) on the levels of bacteria, pro-inflammatory cytokines (PICs), and matrix metalloproteinases (MMPs) in root canals and periradicular tissues of teeth with failure of the root canal treatment and apical periodontitis. MATERIALS AND METHODS: Twenty infected root canals of single-rooted teeth were randomly assigned into two groups according to the irrigant used for chemomechanical preparation (CMP) (n = 10 per group): G1 - 2% chlorhexidine (CHX) gel and G2 - 6% sodium hypochlorite (NaOCl). Root canal contents were taken by using paper points before CMP (S1) and after 30 days of calcium hydroxide-based ICM (S2). Microbial reduction was calculated by means of colony-forming unit count (CFU/mL), with PICs and MMPs (pg/mL) being measured by using enzyme-linked immunosorbent assay (ELISA). RESULTS: Culturable bacteria (101.2 ± 79.2), PICs (IL-1ß 1.2 ± 0.4 and TNF-α 8.8 ± 4.7), MMP-2 (803.7 ± 96.4), MMP-3 (453.9 ± 229.3), MMP-8 (245.9 ± 122.4), MMP-9 (129.4 ± 29.6), and MMP-13 (70.8 ± 12.8) were present in all S1 samples. After 30 days of ICM (S2), a 99.5% microbial reduction was observed, together with a significant reduction of PICs in all groups. Overall, it was observed a decrease in the levels of MMPs (S2), except MMP-13, which was found in increased levels after ICM (P < .05), independently of the groups. CONCLUSIONS: Calcium hydroxide-based intracanal medications have had a positive effect on the microbial reduction by decreasing the levels of PICs and MMPs. Both auxiliary chemical substances (i.e., 2% CHX and 6% NaOCl) presented similar effects when calcium hydroxide was used as intracanal medication. CLINICAL RELEVANCE: Teeth with failure of the root canal treatment and apical periodontitis, and consequently with high levels of bacteria, PIC, and MMP, may present a better prognosis after a 30 days of a calcium hydroxide-based ICM.

The impact of a dental operating microscope on the identification of mesiolingual canals in maxillary first molars.

The aim of this study was to clinically assess the impact of a dental operating microscope (DOM) on the clinician's ability to locate a second canal in the mesiobuccal root (MB2), also known as the mesiolingual canal. An endodontic specialist treated 180 maxillary first molars using the same protocol for all teeth except for the use of the DOM (n = 90 per group). In the teeth treated without the use of a DOM, a mesiolingual canal was located in 26.67% of the cases; when a DOM was used, a mesiolingual canal was located in 77.78% of the cases. Analysis with the Fisher exact test revealed that the magnification provided by a DOM significantly (P < 0.05) improved the identification of MB2 canals in maxillary first molars.

Post-traumatic complications of severe luxations and replanted teeth.

AIM: The aim of this study was to evaluate the main post-traumatic complications of severe luxation and replanted teeth using clinical and radiographic analyses. MATERIALS AND METHODS: Eighty-three patients aged between 7 and 55 years old presenting 180 traumatized teeth that suffered extrusive luxation (n=67), lateral luxation (n=69), intrusive luxation (n=10) and tooth avulsion (n=34) followed by replantation were evaluated. The follow-up period was 24 months. The complications examined were: pulp canal obliteration, pulp necrosis and root resorption (infammatory and replacement). Furthermore, the relationship between time elapsed before receiving dental attendance and development of infammatory resorption was observed. RESULTS: Pulp necrosis was the main complication, occurring in 147 teeth (82.7%). All of the teeth that suffered intrusive luxation and tooth avulsion were diagnosed with pulp necrosis, with significant difference in comparison with another traumas (p<0.001/Fisher's exact test). Infammatory root resorption was observed in 20.5% of the cases and replacement resorption was more related to tooth replantation (94.1%), showing significant prevalence among tooth luxations (p<0.001/Fisher's exact test). In addition, it was noted that patients who seek treatment 9 weeks after the trauma episode presented 10 times more chance of developing infammatory resorption when compared with patients who seek treatment soon after dental trauma (Odds ratio test). CONCLUSION: It may be concluded that pulp necrosis was the main post-traumatic complication observed in traumatized teeth and that delay in seeking treatment may damage the prognosis of severe luxation and replanted teeth. CLINICAL SIGNIFICANCE: Clinical studies describing the main complications that may affect traumatized teeth present great relevance to make the population aware of the importance of seeking immediate treatment and to alert the professional to the need for follow-up. When traumatic injuries are diagnosed and treated early, post-traumatic complications may be controlled, allowing conservation of the tooth in oral cavity.

Analysis of Cutting Capacity, Surface Finishing, and Mechanical Properties of NiTi Instruments 25/.04: ROTATE and LOGIC 2.

INTRODUCTION: In an effort to enhance the quality of mechanized endodontic instruments, various thermal treatment methods, and design modifications have been suggested. However, upon evaluation, these endodontic instruments may exhibit microscopic irregularities. The objective of this in vitro study was to analyze the cutting capacity, surface finish, and mechanical properties of Nickel-Titanium 25/.04 Rotate (VDW GmbH, Munich, Germany) and LOGIC 2 (Easy Equipamentos Odontológicos, Belo Horizonte, MG, Brazil) rotary instruments. METHODOLOGY: Twenty rotary instruments were divided into 2 groups: GR, the group with ROTATE instruments (n = 10); and GL2, the group with LOGIC 2 instruments (n = 10). They were evaluated for roughness, using a profilometer, for bending resistance, buckling resistance, and cutting capacity using a universal testing machine, as well as for torsional strength (torque and angular deflection) using a torquemeter. The instruments were visualized before and after the mechanical tests through scanning electron microscopy. RESULTS: GR showed better surface finish in terms of roughness, greater cutting capacity, and greater angular deflection than GL2 (P < .05). However, GL2 showed better flexibility than GR (P < .05). GL2 and GR did not show statistically significant differences in terms of buckling and torque (P > .05). CONCLUSION: The ROTATE and LOGIC 2 rotary instruments differed in their surface finish, cutting capacity, and mechanical properties, except for their buckling resistance and required fracture torque.

In Vitro Evaluation of the Dynamic Cyclic Fatigue Resistance of a New TruNatomy Glider File after Different Cycles of Use.

INTRODUCTION: Determination of the glide path is recommended before using rotary instruments. This study aimed to evaluate the dynamic cyclic fatigue resistance of new and used glider rotary instruments in up to 6 root canals. METHODS: Seventy-two TruNatomy Glider files were used for the preparation of root canals of extracted lower molars, which were then submitted to the dynamic cyclic fatigue test carried out in a curved metallic artificial canal. The instruments were divided into 4 groups (n = 18): Control group, new instruments without any use in the root canal; Group 2U, instruments used in 2 mesial canals; Group 4U, instruments used in 4 mesial canals; Group 6U, instruments used in 6 mesial canals. The time to failure (TF) of the instrument was recorded, and the number of cycles to failure (NCF) was calculated. The data were submitted to 1-way analysis of variance and to the Games-Howell test for multiple comparisons, adopting a significance level of 5%. RESULTS: TF and NCF were significantly affected by the number of file uses. The Games-Howell test revealed that TF and NCF were significantly greater in the control group than in Group 4U. In Group 2U, TF and NCF were intermediate and not significantly different from the control group. Group 6U had significantly lower TF and NCF than all other groups. CONCLUSION: The TruNatomy Glider can be used as a glide path for up to 2 mesial canals of mandibular molars, whereas its use on 4 or 6 root canals is not suggested.

Development of nanobiosilicate, tricalcium phosphate and chlorhexidine materials for biomineralization with crystallographic similarity to hydroxyapatite and biomodified collagen.

OBJECTIVES: The aim of this work is to test experimental cements, doped with a silicate based bioactive nanoparticle (NanoBiosilicate). Methods, we synthesized a glass nanoparticle by Sol-Gel Stöber method, used to be incorporated in a dental material for endodontic uses. MATERIALS AND METHODS: We assess the mineralizing properties and biocompatibility. Besides the crystallography characterization of the resultant new crystals. Results, After analysis, and comparison with commercial materials, the material tested was similar in mechanical properties required by ISO, The ion release was effective after 2 hr. of setting and the novel material was cell compatible accepted by ISO. RESULTS: We found new formed Calcium Phosphate peaks in the spectroscopic analysis (FTIR), remarkably the crystals formed were comparable to hydroxyapatite when analyzed with a Selected Area Electron Diffractometer, with rings of 2.84 Å for 002, and the 2.77 Å is also visible for 210. The 6.83 Å and 6.88 Å, for respective 222 and 004. The incorporation of Chlorhexidine was not detrimental for this property, Significance, the features mentioned represented a progress in biomineralization field that was associated to an improved mineral structure formation with increased crystallographic similarity to natural hydroxyapatite. When chlorhexidine was added a favorable biomodification of the remaining collagen in dentinal walls and antimicrobial activity potential were also observed.

Effect of EDTA Activation on Blood Clot Structure in Regenerative Endodontics: A Scanning Electron Microscopy Study.

INTRODUCTION: EDTA plays a crucial role in regenerative endodontic therapy (RET) because of its significant biological effects. However, EDTA is also recognized as the preferred anticoagulant for hematologic tests. Thus, this study aimed to assess the influence of different EDTA activation techniques on the morphology of blood clots after conditioning the root canal dentin. METHODS: Forty extracted human teeth were prepared to simulate immature teeth and divided into the following 5 groups: (1) saline solution (negative control), (2) EDTA 17% + saline solution (CNI), (3) CNI + ultrasonic activation, (4) CNI + Easy clean activation, and (5) CNI + XP-endo Finisher activation. After irrigation, the roots were cleaved, and the root canals were filled with human blood to clot formation. The morphology and density of erythrocytes, platelets, and the fibrin network were observed using a scanning electron microscope. The fibrin network density was classified using a 4-point scale. Data were analyzed using the Friedman test and the Kruskal-Wallis test with Bonferroni adjustment (α = 5%). RESULTS: All groups exhibited consistent blood clot morphology characterized by a high density of erythrocytes, platelets, and white blood cells throughout the entire length of the root canal. The negative control group showed statistically significant high scores of fibrin density compared with the CNI group in all root thirds (P < .05). However, there was no statistical difference in the scores for the fibrin network density between the groups irrigated with EDTA with and without activation (P > .05). CONCLUSIONS: EDTA may impair the fibrin network formation compared with the saline group. However, EDTA activation did not significantly change the effects on the blood clot in contact with the conditioned intraradicular dentin.

Prevalence and reasons for referrals to the Endodontics Specialty Clinic at the Piracicaba Dental School.

Dental referrals to the Endodontics Specialty Clinic (ESC) are routine owing to the complexity of endodontic treatments. To obtain a better prognosis for treatment, students/dentists must perceive their technical limits. This study sought to investigate the referrals of patients to the ESC from different clinics of the Piracicaba Dental School, State University of Campinas - SP, Brazil, and check: a) the demographic profile of patients and the most commonly affected tooth; b) the clinic with the largest number of referrals; c) the reasons for referrals; d) the complexity of the cases; e) and the difficulty in assessing the referred cases based on the classification provided by the American Association of Endodontists (AAE) and Souza-Filho. The study sample consisted of patients' electronic dental referral records from February 2015 to June 2019. A total of 1,707 patients were referred to the ESC during the study period, and 62.4% were female. Lower molars were the most frequently involved teeth (34.8%), and 60.7% of the cases were referred due to the presence of root curvature. The AAE classification showed prevalence of highly difficult cases (71.3%), whereas Souza-Filho classification demonstrated a high rate of class III cases (85.8%). This study highlights the difficulties encountered by undergraduate students before or during endodontic treatments, reinforcing the need for clear criteria for selecting cases appropriate for each education level, thus improving endodontic treatment prognosis.

Prevalence of traumatic dental injuries and associated factors among Brazilian schoolchildren.

PURPOSE: To assess the prevalence of traumatic dental injuries to permanent anterior teeth in 9- to 14-year-old schoolchildren attending public schools in Anápolis, Brazil, and to investigate the association between the occurrence of these injuries and the size of incisal overjet and type of lip coverage. MATERIALS AND METHODS: A cross-sectional survey and a two-stage cluster sampling technique were used. The sample size included 765 9- to 14-year-old schoolchildren. Data were collected through clinical examinations and interviews carried out by a trained, calibrated dentist. Oral examinations dealt with the type of traumatic dental injury (TDI), the treatment received, the size of incisal overjet and the type of lip coverage. The teeth examined were maxillary and mandibular incisors. RESULTS: A 16.5% prevalence of dental trauma was found. Boys experienced double the number of girls' injuries. The maxillary central incisors were the teeth most affected, totaling 84.8%. The most frequent type of injury found was enamel fracture (66%), followed by enamel-dentin fracture (27%) and enamel cracks (5%). Only 26% of traumatised teeth were restored. Children with an overjet size > 3 mm were 1.78 times (CI= 1.18 - 2.69) more likely to have a dental injury than children with an overjet size <= 3 mm. Children with inadequate lip coverage were 2.18 times (CI= 1.27 - 3.76) more likely to experience dental trauma than children whose lip coverage was adequate. CONCLUSION: This study shows that the prevalence of traumatic dental injuries among schoolchildren in Anápolis, Brazil is similar to that of other regions in Brazil. The teeth most affected by dental trauma are the maxillary central incisors. Boys run a 2.03-times higher risk of crown fracture than girls, and children with an overjet size > 3 mm are 1.78 times more likely to have dental injuries. In addition, children with inadequate lip coverage are 2.18 times more likely to present traumatic dental injuries than children with adequate lip coverage.

Assessment of the root surface temperature during the use of intracanal agitation systems: In vitro study.

This study aimed to evaluate the temperature changes that the different methods of agitation of irrigants promote on the external dental root surface. Nine extracted human lower premolars were standardized by cone-beam computed tomography and used. The root canal was instrumented with a Reciproc 40.06 file. Temperature measurement was performed using K-type thermocouple sensors attached to the middle, cervical, and apical thirds of the teeth. The teeth had their roots immersed in distilled water at 37ºC, which were distributed into 3 experimental groups according to the mechanical agitation methods to be studied. US Group (n=3), Irrisonic Ultrasonic Tip activated through ultrasound; EC Group (n=3), Easyclean Tip coupled to a contra-angle low-speed handpiece; XP Group (n=3), XP-endo Finisher file coupled to an endodontic electrical motor. Temperature measurements were performed simultaneously with agitation and irrigation of intracanal irrigants. Statistical analysis was performed using SPSS software with a significance level of 5%. For multiple comparisons, the Tukey test was used. The association between mechanical agitation methods and root third was statistically significant. Regarding the temperatures recorded on the external surface of the roots, the ultrasonic tip was significantly higher than the XP-endo Finisher file and the Easyclean tip, which did not differ from each other. Regarding the ultrasonic tip, the external temperature in the middle third (39.46ºC) of the root was significantly lower than in the cervical (40.41ºC) and apical third (40.53ºC). None of the agitation methods of irrigants studied presented heating above 47ºC, and their use is safe for periodontal tissues.