Periapical Lesions Associated with Demographic Variables, Dental Conditions, Systemic Diseases, and Habits.

AIM AND BACKGROUND: The aim of this study was to analyze the prevalence of periapical lesions and possible associations with demographic, dental conditions, systemic diseases, and habit variables in patients from a private Brazilian university. MATERIALS AND METHODS: Data from 452 patients of both sexes, aged 18-78 years, from a Brazilian university were evaluated. Panoramic radiographs were analyzed, and the presence of periapical lesions was recorded. In these cases, the dental condition was assessed for the presence or absence of endodontic treatment. Medical records provide information related to general health (diabetes, cardiovascular diseases, altered cholesterol, autoimmune diseases, gallstones, or kidney stones) and habits (smoking or alcoholism). The data were descriptively analyzed, and then logistic regression and the Wald test were performed in Stata/SE v.14.1. RESULTS: A rate of 58.4% of participants were women, and the mean age was 36.4 (±14.6) years. Periapical lesions prevailed in 193 (42.7%) patients, and 281 (72.4%) teeth were not previously endodontically treated. Mandibular first molars (19%) and men (48.9%) were the most affected. The adjusted model showed that the age group of 26-45 years was 5 times more likely [odds ratio (OR) = 5.01; 95% confidence interval (CI): 2.85-8.82] to have lesions than those aged ≤25 years. Participants aged above 46 years were 19.1 times more prone (OR = 19.1; 95% CI: 10.2-36.0) to morbidity than younger ones (≤25 years). CONCLUSION: The studied sample showed that periapical lesions were more prevalent in males, in mandibular molars, and without prior endodontic treatment. There was no observed association between periapical lesions and comorbidities or habits; however, a significant correlation occurred with advancing age. CLINICAL SIGNIFICANCE: Comorbidities and habits were not associated with the presence of periapical lesions. However, aging has been identified as a significant risk factor for the development of periapical lesions. This finding is clinically relevant as it highlights the importance of monitoring and maintaining oral health in patients with advanced age. How to cite this article: dos Santos VC, de Oliveira Kublitski PM, Marques da Silva B, et al. Periapical Lesions Associated with Demographic Variables, Dental Conditions, Systemic Diseases, and Habits. J Contemp Dent Pract 2023;24(11):864-870.

Intratubular Sealer Penetration: Scanning Electron Microscopy Associated with Cathodoluminescence Analysis.

AIM: The aim of the study was to compare the ability of three endodontic sealers, Endofill (END), AH Plus (AHP), and Sealer Plus BC (SPB), to penetrate dentinal tubules. MATERIALS AND METHODS: Forty-five human teeth, single-rooted and previously instrumented mandibular premolars, were randomly divided into three experimental groups (n = 15): END (n = 15), AHP (n = 15), and SPB (n = 15). After obturation, dental sections were performed horizontally, at 2 and 5 mm from the root apex. The samples were analyzed by scanning electron microscopy associated with cathodoluminescence. Percentage penetration (PP%) and maximum penetration depth (MPD) of the sealers were evaluated by the Kruskal-Wallis and Mann-Whitney tests, for general and paired data, respectively. The Wilcoxon test was applied to analyze the differences between the 5 and 2 mm distances. A 5% significance level was adopted. RESULTS: As for PP%, AHP and SPB were similar (p = 0.127) and presented higher values than END (AHP, p = 0.024 and SPB, p <0.001); with regard to MPD, AHP and SPB did not differ either (p = 0.450), but were higher than END (p <0.001); in both analyses, penetration was greater at 5 mm than at 2 mm (p <0.001). CONCLUSION: SPB showed satisfactory performance in penetrating dentinal tubules, being similar to AHP, and superior to END. CLINICAL SIGNIFICANCE: Greater penetration of sealer into the dentinal tubules may increase the chance of successful endodontic treatment.

Influence of Filling Material Remnants on the Diffusion of Hydroxyl Ions in Endodontically Retreated Teeth: An Ex Vivo Study.

AIM: To assess the influence of remnants of filling material on hydroxyl ion diffusion from calcium hydroxide (CH) paste, measured by the pH value, in retreated teeth. MATERIALS AND METHODS: A total of 120 single-rooted extracted teeth were prepared up to a size 35 hand file and filled. For retreatment, the specimens were divided into four groups (n = 20): ProTaper Universal Retreatment (PUR), PUR with additional instrumentation (PURA), Mtwo Retreatment (MTWR), and MTWR with additional instrumentation (MTWRA). Negative (NEG) and positive (POS) control groups were composed by 20 specimens each one. The specimens, except NEG, were filled with CH paste. The retreated groups were scanned using cone-beam computed tomography (CBCT) for analysis of filling remnants. The pH assessment was performed at the baseline, after seven, 21, 45, and 60 days of immersion in saline. Data were analyzed using Shapiro-Wilk and Levene's test, followed by a two-way analysis of variance (ANOVA) and Tukey's test. RESULTS: Additional instrumentation (PURA and MTWRA) were superior regarding removal of the filling material (p <0.05); however, without significant difference (p >0.05). The mean pH value in all groups increased (p <0.05). After 60 days, no statistical difference was observed among POS and PURA; and MTWR and MTWRA. There was less diffusion of hydroxyl ions when the amount of remnants was greater than 59%. CONCLUSION: Additional instrumentation improved the ability to remove filling material in both systems. All groups presented increasing pH; however, the higher the amount of remnants, the lower the diffusion of hydroxyl ions. CLINICAL SIGNIFICANCE: The amount of remnants allows less diffusion of calcium hydroxyl ions. Thus, additional instrumentation improves the ability to remove these materials.

Anxiety and Sleep Quality in Dental Students at a Private Brazilian University.

The aim of this cross-sectional study was to evaluate the impact of anxiety and quality of sleep on quality of life (QOL) in undergraduate dental students. A total of 141 students were enrolled. All were required to answer the following questionnaires: the State-Trait Anxiety Inventory (STAI) subscale state (S) (STAI-S); the Sleep Assessment Questionnaire (SAQ); and the simplified World Health Organization Quality of Life survey (WHO QOL-bref). The statistical analysis included univariate and bivariate analyses and Poisson regressions. The mean age of the participants was 22.9 (SD=5.2) years; 81.6% were women, and 37.6% studied during the morning shift. The mean STAI-S score was 50.3 (SD=9.4). Sleep problems, classified as "always" or "frequently", were reported by 11.3% and 18.4% of the sample, respectively. Quality of life had a mean score of 13.2 (SD=2.0). The STAI-S and SAQ scores showed a significant association with all WHOQOL-bref dimensions (p<0.05). Analyses performed using multivariate regression and the highest STAI-S score (RR=1.46, 95%CI=1.03-2.06) and SAQ (RR=1.39, 95%CI=1.02-1.90) demonstrated significant sleep problems, even when other variables were controlled to prevent confounding biases. In conclusion, the dental students evaluated showed high levels of anxiety and sleep disorders impacting on QOL.

Training and evaluation of professors of dentistry in postgraduate programmes in Brazil.

INTRODUCTION: In Brazil, the undergraduate dental education still remains fragmented and dissociated from its social context, with emphasis on the individualistic and private aspects of dental health. This study aimed to analyze the training and development of university professors of dentistry in stricto sensu postgraduate programs in Brazil. MATERIALS AND METHODS: Delphi electronic methodology was used within a qualitative-quantitative design to gather data from a panel of 58 experts. Discussions representing the analytic axis focused on: (i) the evaluative processes of higher education, in particular stricto sensu postgraduate programs, and their influence on academic activities in undergraduate dentistry courses and (ii) policies for training and developing university professors. RESULTS: Of the experts, 30 participated in the first round, 24 in the second, and 19 in the third. They considered the training of university professors in dentistry to be highly specialized and technologically focused and indicated the review of political-pedagogic aspects of the educational sphere, as well as the social, economic, cultural, epidemiologic, and professional aspects of training and preparation prescribed by the National Curricular Guides for graduate courses in dentistry. An adequate process of evaluating the official organs and regulators of postgraduate stricto sensu programs, as well the programs themselves, should be implemented. CONCLUSION: The experts stated that changes to the university teaching system are necessary, even in the field of dentistry. Mechanisms for evaluating areas and professors were inadequate, and the training was overly specialized and not consistent with the social reality of the country.

Human Development Index, Ratio of Dentists and Inhabitants, and the Decayed, Missing or Filled Teeth Index in Large Cities.

AIM: This study aimed to investigate the associations between human development and the demographic ratio of dentists with the prevalence of dental caries at 12 years of age in large Brazilian cities. MATERIALS AND METHODS: Data were collected from 27 state capitals, Secondary databases were used: the municipal human development index (MDHI); the ratio of dentists qualified to exercise their profession according to the number of inhabitants; and the decayed, missing or filled teeth index (DMFT). Pearson correlation coefficient analysis and multiple logarithmic regression analysis were performed. RESULTS: The MDHI showed a strong correlation with DMFT and explained 48.1% of the variation in the cities. The ratio of dentists to the number of inhabitants displayed an insignificant, weak correlation with the variations in the DMFT. CONCLUSION: Social factors strongly influence the oral health/ disease process in Brazilian capitals, thus actions are needed for the promotion of health at more distal, or structural levels that modify the environment, thus enabling healthier choices for individuals. These results challenge traditional beliefs that only the ratio of professional dentists to inhabitants and the provision of dental services have beneficial effects on the prevention and control of oral health problems. CLINICAL SIGNIFICANCE: The prevalence of dental caries is strongly correlated with social factors, as the MDHI.

Effect of Endodontic Irrigation Protocols on Crown Fracture Resistance.

AIM: This study aimed to evaluate the fracture resistance of tooth crowns endodontically irrigated using different protocols. MATERIALS AND METHODS: A total of 76 bovine incisors were divided into four groups (n = 19): irrigation with distilled water (control; CON); conventional irrigation with positive apical pressure (PAP); passive ultrasonic irrigation using continuous flushing (PUI); and irrigation with PAP and heated sodium hypo-chlorite solution (PHS). The force required to fracture the crown was measured on a universal testing machine at an angle of 45°. RESULTS: The CON group had higher fracture resistance (351.71 ± 58.66 N) than the PAP and PUI groups (140.96 ± 37.26 N; 167.49 ± 40.08 N respectively). The PHS group had the lowest fracture resistance value (115.15 ± 41.07 N). Irrigation protocols had a significant effect on crown resistance (p < 0.01). CONCLUSION: Teeth subjected to irrigation with heated sodium hypochlorite showed decreased resistance to crown fracture. CLINICAL SIGNIFICANCE: The contact of the irrigating solution with the root canal walls potentially can cause their weakness, determining crown fracture.

Influence of cervical preflaring on apical transportation in curved root canals instrumented by reciprocating file systems.

BACKGROUND: The aim of this study was to evaluate the influence of cervical preflaring on apical transportation in curved root canals prepared using the Reciproc and WaveOne reciprocating file systems. METHODS: Sixty curved canals were instrumented using Reciproc R25 and WaveOne Primary files, with and without preflaring (n = 15). A double-digital technique was used to digitally superimpose the file before instrumentation (#15 K-file) on the final apical reciprocating file (#25/08). The angle between the tip of the initial and final file was measured and recorded. Groups were compared using the Kruskal-Wallis test, and significance was set at p < 0.05. RESULTS: The mean and standard deviation for apical transportation was 0.93 ± 2.48 for the Reciproc Group, 0.84 ± 1.94 for the Preflaring + Reciproc Group, 0.40 ± 1.14 for the WaveOne Group, and 0.83 ± 2.20 for the Preflaring + WaveOne Group. No statistically significant differences were found among the groups (p = 0.9509). CONCLUSIONS: Under the conditions of this study, cervical preflaring did not influence apical transportation in curved root canals instrumented using Reciproc R25 and the WaveOne Primary files. Based on the in vitro measurements of apical transportation, the reciprocating files may be used without preflaring in curved root canals.

Calcium Hydroxide Dressing Influences the Obturation of Simulated Lateral Canals.

AIM: The aim of this study was to investigate the influence of calcium hydroxide dressing on the filling of simulated lateral canals by different obturation techniques. MATERIALS AND METHODS: Sixty single-root-premolars were instrumented. Simulated lateral canals were drilled on each third of the roots. The teeth were divided into four groups: no dressing and obturation by lateral condensation technique (G1), dressing with calcium hydroxide and obturation by lateral condensation technique (G2), no dressing and obturation by hybrid technique (G3) and, dressing with calcium hydroxide and obturation by hybrid technique (G4). The teeth were maintained at 37°C in 100% humidity for 7 days, and obturation techniques were performed. Radiographs were taken and filled or unfilled lateral canals were counted. Data were analyzed using analysis of variance (ANOVA) followed by Tukey's test (a = 5%). RESULTS: The hybrid technique filled large number of lateral canals as compared to lateral condensation technique, regardless the use of intracanal medication (p < 0.05). Calcium hydroxide decreased the number of lateral canals filled for both lateral and hybrid techniques (p < 0.05). Significant differences were observed when comparing the number of filled and unfilled lateral canals in the same root third of each group (p < 0.05). CONCLUSION: Regardless the obturation technique, calcium hydroxide dressing reduced the penetration of filling material in simulated lateral canals. CLINICAL SIGNIFICANCE: The persistence of calcium hydroxide residues reduces the penetration of filling material in simulated lateral canals, possibly representing a potential cause of failure in the future.

Efficacy of calcium hydroxide paste prepared with different vehicles against salivary microbial infiltration of root canals.

This in vitro study evaluated the efficacy of calcium hydroxide Ca(OH)2 pastes prepared with different vehicles in preventing bacterial infiltration in teeth exposed to human saliva. This study used 52 central incisors, of which 4 teeth were used as positive and negative controls (n = 2). The root canals were instrumented and filled with Ca(OH)2 paste prepared with different vehicles: saline solution (Group 1), polyethylene glycol (Group 2), or polyethylene glycol and camphorated paramonochlorophenol (Group 3). Only 6 teeth in Group 1 showed contamination. All teeth in Groups 2 and 3 were contaminated after 32 days of incubation. There were significant differences between Groups 1 and the other groups (P < 0.05) in terms of the mean time to contamination. By contrast, there was no such difference in terms of mean time to contamination between Groups 2 and 3 (P > 0.05). Based on the results, it was possible to conclude that calcium hydroxide paste prepared with saline solution was most effective for retarding microbial contamination.

Correction: The investigation of WNT6 and WNT10A single nucleotide polymorphisms as potential biomarkers for dental pulp calcification in orthodontic patients.

[This corrects the article DOI: 10.1371/journal.pone.0288782.].

Investigation of genetic polymorphisms in genes encoding growth factors and dental pulp calcification in orthodontic patients.

Background and objectives: Pulp calcification is associated with many factors and triggers, including individual genetic predisposition and orthodontic forces. This study aimed to investigate whether genetic polymorphisms in epidermal growth factor (EGF), epidermal growth factor receptor (EGFR1), transforming growth factor-beta 1 (TGFß1), and transforming growth factor-beta receptor 2 (TGFßR2) are associated with a risk of dental pulp calcifications in orthodontic patients. Materials and methods: Digital orthopantomography (OPG) and genomic DNA from 132 patients were analyzed in this cross-sectional study. Pulp calcification was observed in the maxillary and mandibular first molars. Genomic DNA extracted from saliva cells was used to genotype eight genetic polymorphisms using real-time polymerase chain reaction: EGF (rs2237051 and rs4444903), EGFR (rs2227983 and rs763317), TGFß1 (rs1800469 and rs4803455), and TGFßR2 (rs3087465 and rs764522). The association between pulp calcification and genetic polymorphisms was analyzed using allelic and genotypic distributions, and haplotype frequencies (P < 0.05). Results: The prevalence of pulp calcification was 42.4 % in 490 molars. Genotypic analysis and allelic distribution showed no statistically significant association between the evaluated growth factors and molar calcification (P > 0.05). No haplotype combinations showed a statistically significant difference (P > 0.05). Conclusion: The genetic polymorphisms investigated were not associated with dental pulp calcification in orthodontic patients. Further studies should investigate other polymorphisms in genes encoding growth factors.

Investigation of polymorphisms in BMP2, BMP4, SMAD6 and RUNX2 genes and pulp stones.

This study aimed to assess the association between genetic polymorphisms in BMP2 (rs1005464 and rs235768), BMP4 (rs17563), SMAD6 (rs2119261 and rs3934908) and RUNX2 (rs59983488 and rs1200425) and pulp stones (PS). A total of 117 participants, consisting of 63 individuals with PS and 54 without PS, were included. Digital radiographs and a demographic/clinical questionnaire were used. Genomic DNA from salivary cells was genotyped via real-time polymerase chain reaction. Statistical analyses, including Chi-Square, Fisher's exact tests, Poisson regression and dimensionality reduction, were conducted. The rs2119261 polymorphism in the SMAD6 gene showed an association with genotype distribution in the recessive model (p = 0.049). The T-T haplotype in the SMAD6 gene (rs2119261 and rs3934908) was more prevalent in the control group and significantly linked with PS (p = 0.029). No associations were found between PS risk and genetic polymorphisms in BMP2, BMP4 and RUNX2. Polymorphisms in the SMAD6 gene were associated with PS.

[Self-rating of oral health according to the Oral Health Impact Profile and associated factors: a systematic review]. / Autopercepção de saúde bucal conforme o Perfil de Impacto da Saúde Bucal (OHIP) e fatores associados: revisão sistemática.

OBJECTIVE: To systematically evaluate the literature to investigate associations between social, demographic, economic, psychosocial, and behavioral factors and the self-perception of oral health measured using the Oral Health Impact Profile (OHIP). METHODS: In this systematic review of the literature, the Preferred Reporting Items for Systematic Reviews (PRISMA) were adapted for the performance of a qualitative metasummary, without meta-analysis. Articles about oral health and associated factors with implications for quality of life were selected, with a focus on the tool for self-rating of the oral health-disease process, the OHIP. Pubmed/National Library of Medicine (NLM) and the Virtual Health Library (Biblioteca Virtual em Saúde - BVS/BIREME) were searched. Articles published between 2001 and 2011 were included. The following Medical Subject Headings (MeSH) were employed: oral health, quality of life, sickness impact profile, and socioeconomic factors. RESULTS: Of 57 articles identified, 20 met the inclusion criteria. The metasummary revealed that a poor self-perception of oral health was associated with unfavorable social, economic, demographic, and psychosocial factors, as well as with undesirable habits and poor clinical oral conditions. CONCLUSIONS: There is consensus in the literature about the influence of the investigated factors on the self-perception of oral health and on quality of life. The OHIP is an important aid for determining oral health needs and for developing strategies to control/reduce disease and promote oral health, with a consequent positive impact on quality of life.

Retrospective analysis of survival of avulsed and replanted permanent teeth according to 2012 or 2020 IADT Guidelines.

This study aimed to compare the survival of replanted teeth that followed the 2012 or the 2020 International Association of Dental Traumatology (IADT) guidelines. Sixty-two permanent replanted teeth were retrospectively assessed (IADT 2012, n = 45; IADT 2020, n = 17). Five years after replantation (from January 2017 to December 2021), clinical and radiographic examinations were performed. A significance level of 95% was considered to evaluate the outcomes. Thirty-one teeth (50.0%) remained in their sockets and 31 (50.0%) were lost due to external root resorption. Of the 25 (40.3%) teeth replanted within one hour, 16 (64.0%) remained in their sockets, and 9 (36.0%) were lost. Twenty-two (71.0%) of all 31 lost teeth had an extra-alveolar time of more than one hour. Twelve teeth remained in their sockets without resorption: 8 (66.7%) were replanted within one hour, 2 (16.7%) followed the 2012 IADT, and 2 (16.7%) the 2020 IADT guidelines for late replantation. There was a significant difference (p <0.05) in the extra-alveolar time (< one hour), but without difference between the guidelines in late replantation (p > 0.05). Replanted teeth following both, 2012 or 2020 IADT guidelines, have similar clinical outcomes. The extra-alveolar time of less than one hour was demonstrated to be important to keep the permanent tooth in its socket.

Dynamic Cyclic Fatigue Resistance of Heat-treated Nickel Titanium Instruments in Reciprocating Motion.

OBJECTIVE: To compare the fatigue resistance of different heat-treated reciprocating instruments tested in a dynamic cyclic fatigue model. METHODS: Forty-eight new instruments were inspected under magnification and selected for this study, and then divided as follows (n=12): X1 Blue (MK Life, Porto Alegre, RS, Brazil), Pro-R (MK Life), Reciproc (VDW, Munich, Germany), and Reciproc Blue (VDW). Artificial canals presenting a curvature of 60° angle and 5 mm radius were milled in zirconia. The block containing the artificial canals was mounted in a container filled with water kept at 37°C. A specially designed device was used to perform controlled axial movements while the instruments were activated inside the canals. Time to failure was recorded in seconds, and fragment lengths were measured (mm). Data were analyzed statistically with the significance level set at 5% (One-Way ANOVA and Tukey test). RESULTS: Pro-R and Reciproc Blue instruments presented the highest fatigue resistance, being significantly different from the other tested files (p<0.05). Reciproc presented intermediate results, significantly different X1 Blue (p<0.05). The fractographic analysis showed typical features of cyclic fatigue for all instruments. CONCLUSION: Pro-R and Reciproc Blue instruments are more resistant to dynamic cyclic fatigue than the Reciproc and X1 Blue. (EEJ-2022-10-124).

Educational approaches for assessing knowledge about and actions of educators in response to dental avulsion.

BACKGROUND: Dental trauma affects especially schoolchildren and adolescents. Educators, the responsible for the first appointment, have a fundamental role in the prognosis of dental avulsion that occurred in this environment. AIM: To evaluate the educational approaches for assessing knowledge and actions in response to dental avulsion among educators. SETTINGS AND DESIGN: This cross-sectional and quanti-qualitative study included 197 teachers and 24 pedagogical coordinators (PCs), from the public schools of Pato Branco, Paraná, Brazil. METHODS: A questionnaire was initially administered regarding the knowledge about avulsion to all participants. Teachers just read a manual and answered the questionnaire after 30 days. PCs were divided into (n = 12): G1 - manual + fictitious scenario of avulsion and G2 - active methodology + fictitious scenario. The questionnaire was re-administered to all. STATISTICAL ANALYSIS: Quantitative data were analyzed statistically. For the qualitative stage, two questions were proposed and the Bardin's analysis was performed. RESULTS: For teachers, knowledge about avulsion increased after the intervention (P < 0.001), except as related to cleaning the tooth (P = 0.21). Activities involving G1 and G2 also led to an increase in knowledge, but no difference occurred in this increase between the approaches (P = 0.14). Qualitative analysis highlighted the need for calm and for performing actions that could favor a good prognosis in cases of avulsion. CONCLUSIONS: The level of knowledge increased after interventions, but no significant differences between the educational approaches were found.

Postoperative Pain after Endodontic Treatment under Irrigation with 8.25% Sodium Hypochlorite and Other Solutions: A Randomized Clinical Trial.

INTRODUCTION: The aim of this study was to evaluate the postoperative pain in patients after endodontic treatment using 8.25% sodium hypochlorite (NaOCl) compared with other concentrations and 2% chlorhexidine (CHX). METHODS: In this double-blind randomized trial, 180 patients were evaluated who underwent a single session of endodontic treatment under irrigation with 2.5%, 5.25%, or 8.25% NaOCl or 2% CHX solutions. The presence of postoperative pain was assessed 24, 48, and 72 hours after treatment and recorded using the visual analog scale (VAS). A descriptive analysis, logistic regression, and Wald test were performed. RESULTS: Altogether 169 patients participated, of whom 107 were women, and the mean age was 38.1 ± 14.4 years. No significant differences occurred between the irrigants and the pain outcomes, not even for the use of postoperative pain medication and responses to VAS (P > .05). In the multivariate model including irrigants, after 24 hours or at any time, a significant difference (P < .05) remained in preparation time ≥10 minutes and the presence of overfilling. Also, in relation to the VAS, the overfilling presented significantly different results (P < .05). CONCLUSIONS: There was no significant difference in the presence of postoperative pain between the 8.25% NaOCl and the other irrigation solutions. However, the extended preparation time and the overfilling material were responsible for the increase of postoperative pain.

Biocompatibility of the 8.25% sodium hypochlorite irrigant solution in endodontics: An in vivo study.

The biocompatibility of irrigant solutions, including 8.25% sodium hypochlorite (NaOCl), was analyzed in samples (n = 25) of chorioallantoic membranes (CAM) from embryos of the Gallus gallus, using the hen's egg test on chorioallantoic membrane (HET-CAM). The following irrigants were tested: saline (control), 2% chlorhexidine (2% CHX), and NaOCl (2.5%, 5.25%, and 8.25%), and morphological and microcirculatory changes were investigated. Images were selected and quantified with Image J®. The macroscopic data were submitted to ANOVA, followed by the Tukey's test (p < .05); non-parametric Kruskal-Wallis and Mann-Whitney tests were applied to histological data (p < .05). The frequency of hyperemia differed significantly in the 8.25% NaOCl compared to the other groups, with the exception of 5.25% NaOCl (p = .096). Coagulation was more frequent in the 2% CHX group, differing significantly from the 2.5% NaOCl group (p = .038). In mean values, NaOCl 8.25% caused the decrease (NaOCl = 2.60, and control = 5.00) of vessels in the microcirculation, as well as triggered the increase (NaOCl = 425.50, and control 44.50) of inflammatory cells in the observed areas. There was necrosis in all samples in the 5.25% NaOCl group and in 80% in the 2% CHX, 2.5% NaOCl, and 8.25% NaOCl groups. Fibroblasts were detected only in the control group. It was concluded that the 8.25% NaOCl solution showed significantly high toxicity on CAM. However, these results were comparable to the other concentrations of NaOCl and to 2% CHX. Thus, in this experimental protocol, 8.25% NaOCl proved to be viable as an irrigant solution.

Radiofrequency therapy in esthetic dermatology: A review of clinical evidences.

BACKGROUND: Chronological skin aging causes the modification of genetic material through enzymes and proteins changes. The process reduces cellular proliferation, along with loss of tissue elasticity, reduced ability to regulate aqueous exchanges, and inefficient tissue replication. Appearance is negatively affected by cumulative changes in coloration, texture, and elasticity over time. The increase in the population's average life expectancy boosts the search for cosmetic therapies that can delay aging, mostly for the noninvasive modalities. Among the various options, radiofrequency therapy is a technique that can help reduce the effects of skin aging. AIM: Therefore, this study aims to review clinical evidence provided by scientific literature on the benefits of using radiofrequency therapy in reducing skin aging effects. METHODS: A review of the literature concerning skin aging, characteristics of radiofrequency therapy, and radiofrequency therapy in the treatment of skin laxity and mechanism of action was conducted using PubMed. RESULTS: The included studies have suggested that the mechanism of radiofrequency action is heating the dermis while preserving the epidermis. This heating causes immediate collagen denaturation, which is followed by the formation of new collagen, naturally providing skin tightening and greater elasticity. CONCLUSION: Even when used as single therapeutic modality, radiofrequency seems to meet the expectations in reducing the effects of skin aging.