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Objective: To evaluate the penetration of hydrogen peroxide (HP) into the pulp chamber and the color change of different bleaching varnishes in low concentrations used for at‐home bleaching. Materials and Methods: Ninety healthy premolars were used, randomly distributed into nine groups (n = 10) according to bleaching varnish (PL, PolaLuminate; VS, VivaStyle Paint On Plus; CA, Cavex Bite&White whitening pen and; AW AlignerWhite) and time (10 and 30 min), and a control group (no bleaching). The penetration of HP was evaluated by UV–Vis spectroscopy. To evaluate the color change (ΔEab, ΔE00, ΔWID) a digital spectrophotometer was used (α = 0.05). Results: The AW group in 10 min and the control group showed similar and lower HP penetration in the pulp chamber when compared to the other groups (p = 0.003). Increasing the application time to 30 minutes elevated the amount of HP inside the pulp chamber for all groups (p = 0.003), except for PL (p > 0.05). When applied for 30 min all bleaching varnishes showed higher color change (ΔWID) when compared to 10 min (p = 0.04). Conclusions: For all bleaching varnishes evaluated, PolaLuminate applied for 30 min showed lower penetration into the pulp chamber and higher bleaching effects. Clinical Significance: The use of bleaching varnishes seems promising for teeth bleaching, but it varies according to user product and protocol. [ABSTRACT FROM AUTHOR]

Background/Aim: External inflammatory root resorption (EIRR) and external replacement root resorption (ERRR) are the most common adverse outcomes after luxation injuries or dental injuries. They are usually detected radiographically after considerable progression. It can be envisaged that evaluation of inflammatory mediators might serve as an objective and reliable method of predicting the risk of resorption. The aim of this systematic review was to assess the evidence regarding the risk of resorption and to provide future research directions. Methods: An a priori protocol was prepared by a multidisciplinary expert group, as per the Cochrane handbook and PRISMA guidelines. The systematic search was conducted in six databases and grey‐literature sources. Scrutiny of titles and abstracts, and later full‐text articles was performed, and data were extracted. Risk of bias analysis was done by using the Joanna Briggs Institute's Critical Appraisal Checklist for analytical cross‐sectional and cohort studies. Results: Eight studies were included in the systematic review and could be categorized as per the source of biomarkers, namely epithelial cells from mucosa, gingival crevicular fluid and extracted teeth. The studies utilizing epithelial cells had been conducted between 2015 and 2018 in Brazil and did not find any correlation with EIRR. Two of the studies with extracted teeth found differences in the immunologic profiles of teeth with resorption. Three studies evaluating gingival crevicular fluid found increased levels of dentine sialoprotein and Interleukin‐1‐α. Conclusion: Among the three sources, the inflammatory gingival crevicular fluid appeared to be the most non‐invasive source of biomarkers for predicting trauma‐induced root resorption, although the evidence about this came from two studies with moderate and one study with high risk of bias. The primary studies in this systematic review showed variability in terms of the sample sizes, age of the patients, the grading/classification of trauma‐induced resorption and the evaluation methods which must be addressed by future researchers. [ABSTRACT FROM AUTHOR]

The objective of the research was to examine the scientific literature concerning restorative materials with bioactive properties for the purpose of covering dentin. Searches were performed in various databases including MEDLINE, Scopus, Web of Science, Cochrane Library, Lilacs/BBO, and Embase. Inclusion criteria involved studies that utilized the terms "dentin" and "bioactive", along with "ion-releasing", "smart materials", "biomimetic materials" and "smart replacement for dentin". The information extracted included the title, authors, publication year, journal and the country of affiliation of the corresponding author. The studies were categorized based on their study design, type of material, substrate, analytical method, and bioactivity. A total of 7161 records were recovered and 159 were included for data extraction. Most of the publications were in vitro studies (n = 149), testing different types of materials in sound dentine (n = 115). Most studies were published in Dental Materials (n = 29), and an increase in publications could be observed after the year 2000. Most of the articles were from the USA (n = 34), followed by Brazil (n = 28). Interfacial analysis was the most investigated (n = 105), followed by bond strength (n = 86). Bioactivity potential was demonstrated for most tested materials (n = 148). This review presents insights into the current trends of bioactive materials development, clearly showing a severe lack of clinical studies. [ABSTRACT FROM AUTHOR]

To evaluate the effect of photo-polymerized composites and universal adhesive modes on µ-tensile bond strength (µTBS) of a CAD/CAM composite to dentin. Human molars (N=60) were randomly assigned to 12 groups (n=5 teeth/group) according to the two experimental factors, Factor 1: Luting resin [Bifix QM "BF", Grandio flow "GF", GrandioSO Heavy Flow "GHF", Grandio "GR", x-tra fil "XTF", and VisCalor Bulk "VCB" (VOCO GmbH; Germany)] and Factor 2: Adhesive mode, Etch-and-rinse "ER" and Self-etching "SE" (OptiBondTM Universal, Kerr Orange, CA, USA). CAD/CAM blocks were air-abraded (50μm Al2O3/10 s/0.2 MPa, MicroBlaster; bio-art; Brazil) and silane was applied (60 s) and air dried (10 s). Dentin surfaces were wet ground (#600 SiC/30 s). For E&R, 37% phosphoric acid (Meta Etchant, Meta Biomed, S. Korea) was applied (15 s), rinsed (30 s) and blot dried. For both E&R and SE, adhesive was applied (20 s), air dried (5 s) and photo-polymerized (10 s) using LED unit (EliparTM DeepCure-L, 3 M ESPE, USA). GR and XTF were pre-heated (65°C/70 s), while VCB was heated (65°C/30 s) before application. Pre-heating was not performed for BF, GF and GHF. CAD/CAM blocks (7x7x4mm3) were positioned, and luting materials were photo-polymerized (40 s/each side). Cemented specimens were sectioned into 1mmx1mm rods. For each group, half of the rods was tested after 24 h and the other half after 6 months. All fractured rods were evaluated for failure mode analysis. Statistical analysis was performed using Welch ANOVA/ Games-Howell post hoc test (α=0.05). Factors "luting resin" and "aging" showed significant effect on µTBS (p<.001). However, factor "adhesive mode" had no significant effect (p=.079). For 24 h, VCB revealed the lowest significant µTBS in SE (21.1±6.1 MPa), while GR showed significantly higher µTBS in E&R (41.7±11.3 MPa). A significant difference was noticed between SE and E&R modes for GHF, Gr and VCB (p<0.05). Among 6 months aged groups, VCB showed significantly lower µTBS (14.9±6.3 MPa) in SE, while VCB showed significantly lower µTBS (19.8±11.3 MPa) compared to GR (32.1±13.1 MPa) in E&R. Significant difference was observed between SE and E&R modes in BF, GHF and GR (p<0.05). For SE, significant drop in µTBS was shown for all luting materials after 6 months (p<0.05), except for XTF (P>0.05). For E&R, significant decrease in µTBS was noticed for GF, GR and VCB after 6 months (p<0.05). Adhesive mode represents 73.1%, mixed 26.9% and cohesive 0.0%. Photo-polymerized composites can be used as alternatives to dual-cured resin cement for CAD/CAM composite bonding to dentin. [ABSTRACT FROM AUTHOR]

Introduction: Fiberglass Posts (FGPs) associated with composite resin foundation materials have become the primary alternative to restoring teeth with root canal treatment presenting excessive coronal destruction. Despite technical evolution, loss of retention between FGP and root dentine continues to be reported. Aim: To examine the effect of endodontic retreatment protocols on the bond strength of FGP to radicular dentine. Materials and Methods: This in-vitro study was conducted at Evangelical University of Goiás, Brazil from August 2019 to June 2020. A total of 30 freshly extracted bovine incisors were instrumented, filled and distributed into three experimental groups with 10 incisors in each groups. Group 1 was control, group 2 had incisors with gutta-percha removed using K-type files and group 3 had incisors with gutta-percha removed using ProTaper Universal Retreatment instruments. After root canal retreatment and re-sealing, the fiber posts were cemented into prepared post spaces using a resin-based cement. Roots were transversally sectioned into six 1 mm thick specimens. The pushout test was performed, and the modes of failure were evaluated. Data were analysed with two-way Analysis of Variance (ANOVA) and Tukey's test. Results: There was no significant difference between the mean bond strength values in group 1, 2 and 3 with p-value >0.05. The cervical third of root canal presented higher bond strength values compared with the middle and apical thirds. However, significant differences were observed only for the control group (p-value=0.005). Adhesive failure between resin cement and radicular dentine was the most prevalent type of failure. Conclusion: The endodontic retreatment protocol did not influence the bond strength of FGP to radicular dentine. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the color change stability and patient satisfaction after one‐year of at‐home bleaching with 10% carbamide peroxide (CP) in trays with or without reservoirs. Materials and methods: Forty‐six patients were subjected to bleaching with CP (3 h/daily; 21 days) with a bleaching tray with or without reservoirs. The color was measured one‐month and one‐year after the completion of bleaching using the spectrophotometer (ΔEab, Δ00 and ΔWi), and shade guide units (ΔSGU). Patients' satisfaction were assessed using a 5‐point Likert Scale questionnaire. Data were submitted to paired t‐test (α = 0.05). Results: No significant difference between color change after one‐month and one‐year was observed (VITA Classical shade guide unit and the ΔWi; p > 0.53). Significant differences were observed for the VITA Bleachedguide 3D‐MASTER shade guide, ΔEab and ΔE00 (p < 0.03). The level of patient satisfaction was similar between groups (p = 1.00). Conclusions: Bleaching tray design did not have any influence on the bleaching stability for the 10% CP (Opalescence PF, Ultradent). Patients were very satisfied with the bleaching outcomes regardless of the bleaching tray design. Clinical relevance: Placement of reservoirs in bleaching trays does not increase longevity of dental bleaching. No clinically important color rebound was observed 1 year after bleaching with 10% CP. [ABSTRACT FROM AUTHOR]

This study aims to determine whether the design of resin posts reinforced with glass fiber (FRC) and Reporfost (Angelus, Londrina, PR, Brazil) significantly improves the fracture resistance of endodontically treated teeth restored through this method.A batch of 30 maxillary monoradicular teeth (15 central incisors, 15 canines) were treated endodontically by step-back technique (apical enlargement 40-K file) sealed with Sealapex (Kerr Corporation, Orange, US) and gutta-percha by lateral condensation, cold. They were divided into two equal groups, prepared for cementing the FRC posts. The Exacto posts (Angelus, Londrina, PR, Brazil) in group 1 and the Reforpost posts (Angelus; Londrina; PR, Brazil) were cemented with dual cure resin cement Breeze Self-Adhesive Resin Cement (Pentron Clinical, Orange, US). Fracture resistance testing was performed on the crown-apical axial direction, using the Hounsfield / Tinius Olsen H1-KS, PA, USA mechanical testing apparatus. The behavior of each tooth-post assembly was recorded as a graph. The statistical analysis was done using one way ANOVA (a=0.05). The differences between the Exacto post group and the Reforpost post group are not statistically significant (p = 0.466). The maximum force recorded was 970 N and the minimum 186N. The mean force at which the fracture occurred was approximately 500N for both groups. The strain test showed that modifying the Reforpost post design did not improve the fracture resistance parameters of the tooth-post assembly through increasing the surface friction or maintaining adhesion to the walls of the root dentin. [ABSTRACT FROM AUTHOR]

The aim of this retrospective study was to evaluate the survival and associated factors for the longevity of direct posterior restorations and to verify whether the geographic location of public health units could influence the long-term survival of such restorations. Data were extracted from electronic patient files of the Brazilian public oral health services. The sample comprised 2,405 class I and II restorations performed 4 to 24 years ago (mean, 8.9 years) in 351 patients (6.8 teeth/patient) across 12 public health units located in different city regions (42 professionals—55 restorations). The restoration was considered successful if it had not been repaired or replaced at the time of evaluation; failure was defined as replacement of the restoration, the need for endodontic treatment, tooth/restoration fracture or tooth extraction. Data were analyzed using the Kaplan-Meier test for restoration survival and Cox regression to evaluate the factors associated with failure. The majority of the restorations involved the use of amalgam (85%), involved a single face (70%), and were without pulp/dentin capping (85%). The overall survival rate was 95%, and the mean observation time was 8.9 years. The restoration survival was 79% (95% CI: 60.6–89.5) over 24 years, and the mean survival time was 22.2 years (95% CI: 21.9–22.6 years). The annual failure rate up to 24 years was 0.9%. After the adjustment, only the number of restored faces and the geographic location where the restoration was performed remained associated with failure of the restoration. The direct posterior restorations performed at the evaluated public health service units presented high survival rates. The restorations of people with lower access to POHS had lower survival rates. Class I restorations presented higher survival rates than class II restorations with two or more faces, regardless of the restorative material used. [ABSTRACT FROM AUTHOR]

Homeless people are usually more exposed to traumatic events that may cause dental injuries than those with more stable housing. Previous studies on the oral health condition of this population group have shown high levels of dental caries, periodontal diseases, and tooth loss, but evidence on dental trauma is scarce. Furthermore, there is no report from Latin American countries. The aim of this study was to describe the prevalence of untreated traumatic dental injuries (TDI) among adult homeless people in a Brazilian capital city. A sample of 102 adults attending a public homeless shelter was clinically examined using the criteria of the 2010 Brazilian National Oral Health Survey. TDI was found in 10.8% of the participants, and the most common types of injury were enamel‐dentin fractures and avulsion. The overall prevalence was relatively low, but the proportion of anterior tooth loss due to trauma and other reasons shows the need for more appropriate health care for this vulnerable population group. [ABSTRACT FROM AUTHOR]

Background/aims: Among the diseases related to oral health, such as caries and oral cancer, dental trauma stands out as one of the major public health problems worldwide. The aim of this study was to verify the occurrence of factors associated with traumatic dental injuries (TDIs), including oral health-related quality of life (OHRQoL), sociodemographic characteristics, untreated caries, occlusal problems and contextual variables in 12-year-old Brazilian children.Methods: This study assessed a complex sample of the National Research in Oral Health (SBBrasil 2010) data on 7240 12-year-old children and contextual features of the municipalities where they lived.Results: TDI prevalence in 12-year-old schoolchildren was 23.96%. Being female was a protective factor for all trauma outcome variables. Non-white children were at risk of maxillary tooth fractures. Maxillary overjet greater than 3 mm was associated with all trauma outcomes. Crowding and spacing were risk factors for enamel trauma. TDI has a negative impact on OHRQoL. None of the contextual variables analysed (Gini coefficient, MHDI, family health strategy and water fluoridation) were associated with TDI in the multilevel approach.Conclusions: TDI was better explained by individual factors, related to sociodemographic conditions and occlusal problems, with a negative impact on OHRQoL, adjusted for untreated caries. Contextual variables were not associated with TDI in 12-year-old Brazilian schoolchildren. Interdisciplinary actions for preventing dental trauma, such as stimulating the use of mouthguards, have to be encouraged by the family health strategy (FHS) and school health programme (SHP). [ABSTRACT FROM AUTHOR]

Absolute dating of sedimentary rocks and fossils from the Mesozoic are still rare, mainly due to the difficulties arising from diagenetic changes. Diagenesis promotes changes in the primary structure and chemical composition of biomineralization, which should remain unchanged from the time of deposition and fossilization. Three bioapatite teeth extracted from a jaw fragment of Cladocyclus gardneri from the Romualdo Formation, Araripe Basin, Northeastern Brazil were dated by the U/Pb method in order to obtain an absolute age. The rocks that contain this fossil are dated to Aptian by biostratigraphy of palynomorphs (Sergipea variverrucata biozone, Petrobras P-270), ostracods (Damonella grandiensis biozone, Petrobras) and from the international biozoning of planktonic foraminifera Microhedbergella miniglobularis. The teeth were mounted in 25 mm epoxy resin rounds, imaged by optical microscope and SEM and dated with a Nu Instruments AttoM single-collector ICP-MS coupled to an NWR193nm UC (Ultra Compact) ArF excimer laser system. A Discordia U–Pb date obtained from three separate Cladocyclus gardneri dentine is 110.5 ± 7.4 Ma (2s, MSWD = 2.6), consistent with the biostratigraphic age. This date was based on 155 integrations of line scan analyses (spot size of 30 μm, scan moved at 2 μm per second/100 μm in total length). 238U/206Pb ratios that differed from the mean value by more than 2SD for each tooth were excluded based on the likelihood they reflect U-redistribution during fossilization/post-fossilization fluid alteration. Remaining variations in 238U/206Pb and 207Pb/206Pb ratios along the Discordia reflect variable contributions from common Pb, both within and between the three teeth. They reflect primary U/Pb compositions given that they date the expected age of fossilization. • Direct dating on fossils is still a challenge to be overcome in Geochronology. • Biomineralized parts are more likely to be preserved in the fossilization. • First absolute dating result for the Romualdo Formation, Araripe Basin. • The U–Pb dating corroborates biostratigraphy data. [ABSTRACT FROM AUTHOR]

Statement of the Problem The effect of the intraoral environment during adhesive restorative procedures remains a concern, especially in the absence of rubber dam isolation. Objective To evaluate the temperature and relative humidity ( RH) at anterior and posterior intraoral sites and their effects on the dentin bond strength of two-step etch-and-rinse adhesive systems. Methods Sixty human molars were assigned to six groups according to the adhesive systems ( Adper Single Bond Plus and One Step Plus) and intraoral sites (incisor and molar sites). The room condition was used as a control group. Dentin fragments were individually placed in custom-made acetate trays and direct composite restorations were performed. The intraoral temperature and RH were recorded during adhesive procedures. Then, specimens were removed from the acetate trays and sectioned to obtain multiple beams for the microtensile bond strength test. In addition, the adhesive interface morphology was evaluated through scanning electron microscopy. Intraoral conditions were statistically analyzed by paired Students' t-tests and the bond strength data by two-way analysis of variance and Tukey test (α = 0.05). Results The posterior intraoral site showed a significant increase in the temperature and RH when compared with the anterior site. However, both intraoral sites revealed higher temperatures and RH than the room condition. In regards to the adhesive systems, the intraoral environment did not affect the bond strength, and the One Step Plus system showed the highest bond strength means. Conclusion Despite the fact that remarkable changes in the intraoral conditions were observed for both anterior and posterior sites, the intraoral environment was not able to compromise the immediate dentin bond strength. Clinical Significance Some conditions of intraoral temperature and relative humidity may not impair the dentin bond strength of two-step etch-and-rinse adhesive systems. Thus, an adequate relative isolation seems to be a good alternative under the specific clinical conditions in which rubber dam isolation is either impossible or very difficult to perform. [ABSTRACT FROM AUTHOR]

Purpose To evaluate the 18-month clinical performance of four adhesive strategies in posterior composite restorations placed in private practice. Materials and Methods Upon approval by an institutional review board, 144 restorations were inserted in 45 subjects (average age = 32.6) to treat caries lesions or to replace existing restorations in vital molars and premolars. The adhesives Opti Bond FL (three-step etch-and-rinse), Opti Bond SOLO Plus (two-step etch-and-rinse), Opti Bond XTR (two-step self-etch), and Opti Bond All-in One (one-step self-etch) were applied as per manufacturer's ( Kerr Co.) instructions followed by a nanofilled resin composite ( Filtek Z350 XT, 3 M ESPE) under rubber dam isolation. Restorations were evaluated at baseline and at 18 months using United States Public Health Service ( USPHS)-modified criteria and high-resolution digital photographs. Statistical analyses included the Mc Nemar and the Mann- Whitney non-parametric tests ( p < 0.05). Results A total of 137 restorations were evaluated after 18 months. The number of alfa ratings did not change significantly from baseline to 18 months for any of the adhesion strategies. When the 18-month evaluation criteria were pooled by pairs of adhesives, none of the adhesives resulted in a significantly different number of alfa ratings for any of the criteria compared with the other adhesives. Conclusion Bonding strategy did not influence the clinical performance of posterior composite restorations under the clinical conditions used in this study. Clinical Significance When used in ideal clinical conditions, the composition of current dentin adhesives may be more clinically relevant than their adhesion strategy. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to evaluate the effectiveness of partial removal of carious dentine and restoration in a single session (PDR) and stepwise excavation (SW), both of which are treatments for deep carious lesions, in Public Health Services in Brazil. Methods: Inclusion criteria: patients ≥6 years old, permanent molars with deep caries lesions (having a radiolucency halfway or more into dentine) and pulp vitality but absence of spontaneous pain, positive percussion test, and periapical alterations. The subjects received either PDR (test group) or SW (control group). The radiological and clinical exams were performed after a mean time of 18 months. Outcomes: success was defined as pulp sensitivity to cold test and absence of periapical alterations. Results: Of the 299 treatments performed, 146 were SW and 153 were PDR; 122 were amalgam restorations and 168 resin-composite restorations. There were no differences between the groups regarding the baseline characteristics (i.e. age, gender and family income). After 18 months, 212 evaluations were performed, which indicated 99 and 86% success rates in the PDR and SW groups, respectively (p = 0.016). Reasons for failure were: PDR - 1 pulpitis; SW - 8 pulpitis; 1 osteitis; 4 necrosis; 1 endodontic treatment. None of the baseline variables were significantly associated with the outcomes. Conclusion: The retention of carious dentine does not interfere in pulp vitality. Data from this 18-month study suggest that the procedure of reopening the cavity to remove the residual infected dentine is not necessary. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to evaluate the effect of a flowable glass ionomer cement (GIC) layer application on bond strength to sound (SD) and carious primary dentin (CD). Methods: Flat dentin surfaces from primary molars were randomly assigned to 4 groups (n=5) according to substrate (SD or CD; pH-cycling for 14 days); and layers of GIC (1 layer/control [regular powder/liquid ratio] or 2 layers [first a flowable GIC layer and second a regular powder/liquid ratio layer of GIC]). After 24 hours of water storage, specimens were prepared to be evaluated with the microtensile test (1 mm/ min). The fracture pattern was evaluated at 400X magnification (stereomicroscope). Results: The bond strength to SD was higher than to CD when GIC was inserted in 2 layers (P=.02). No significant difference was observed between 1 or 2 layers of GIC insertion (P>.05). For all groups, adhesive/mixed fracture prevailed. Conclusion: The effect of applying the flowable GIC layer on bond strength to dentin is dependent on substrate and results in an increase in adhesion for sound primary dentin. [ABSTRACT FROM AUTHOR]

Abstract: Forensic age estimation is an important element of anthropological research, as it produces one of the primary sources of data that researchers use to establish the identity of a person living or the identity of unknown bodily remains. The aim of this study was to determine if the chronology of third molar mineralization could be an accurate indicator of estimated age in a sample Brazilian population. If so, mineralization could determine the probability of an individual being 18years or older. The study evaluated 407 panoramic radiographs of males and females from the past 5years in order to assess the mineralization status of the mandibular third molars. The evaluation was carried out using an adaptation of Demirjian''s system. The results indicated a strong correlation between chronological age and the mineralization of the mandibular third molars. The results indicated that modern Brazilian generation tends to demonstrate an earlier mandibular third molar mineralization than older Brazilian generation and people of other nationalities. Males reached developmental stages slightly earlier than females, but statistically significant differences between the sex were not found. The probability that an individual with third molar mineralization stage H had reached an age of 18years or older was 96.8–98.6% for males and females, respectively. [Copyright &y& Elsevier]

Purpose: The purpose of this in vitro study was to evaluate, via scanning electron microscopy, the micromorphology of the dentine walls of primary anterior teeth with focus on the presence of the smear layer after endodontic debridement and final irrigation with different systems. Methods: Thirty primary maxillary anterior teeth were assigned to 3 groups according to the final irrigant solution. Group 1 received 1% sodium hypochlorite; Group 2 received 17% EDTA followed by 1% sodium hypochlorite; and Group 3 received 6% citric acid followed by 1% sodium hypochlorite. The canals were debrided using 1% sodium hypochlorite to a size 30 file, and the final irrigation was performed with one of the 3 irrigants as assigned. The teeth were prepared for examination of the canal walls by electron microscopy for the presence or absence of the smear layer. Results: Group 1 had significantly higher scores for remaining smear layer than Groups 2 and 3 (P<.01), while Groups 2 and 3 presented similar smear layer score values. Conclusions: Sodium hypochlorite promoted the formation of a smear layer during shaping, and the use of EDTA and citric acid facilitated smear layer removal. [ABSTRACT FROM AUTHOR]

The article presents a study that evaluated the application of etch-and rinse adhesive on dry and wet demineralized dentin. About 40 patients have been enrolled in the study wherein 160 restorations have been made into four groups. The group with the wet and dry condition showed retention rates of 95 and 97.5 percent, respectively for Adper Single Bond and 97.5 and 91.9 percent, respectively, for One-Step (OS). Concluded is that dentin moisture has no importance for the retention of adhesives.

Objective: This study investigated the prevalence of dental wear in 12-year-old adolescents using a modification of the tooth wear index (TWI). The modifications were proposed in order to fit with the World Health Organization standard, thus allowing application of the index in broad epidemiological surveys. Study design: An epidemiological cross-sectional survey was performed by trained, calibrated examiners, using a modified version of the TWI. Methods: Urban elementary schools were chosen because they provide a fair representation of the city's population in terms of socio-economic status. The sample included 295 adolescents, selected randomly and systematically. Dental wear was assessed by calibrated examiners (kappa > 0.85), using a modified version of the TWI. This modified version includes a code for teeth restored due to wear, and another code for teeth that cannot be assessed. In addition, it does not differentiate the depth of dentine involvement. Proportions and confidence intervals were used to describe the prevalence of dental wear. Mann-Whitney test was used to detect differences in the degree of dental wear between males and females. The level of statistical significance was set at 5%. Results: In total, 24,780 dental surfaces were evaluated. Among these surfaces, 73.10% did not present dental wear, 24.10% had incipient lesions, 2.46% had moderate lesions and 0.34% had been restored. No severe lesions were detected. Tooth wear was mainly seen on the occlusal/incisal surfaces (26.55%), involving enamel or enamel-dentine, but not the secondary dentine or pulp. The prevalence of dental wear was 26.90%. Considering the different teeth, wear was present in 53.22% of incisors, 50.51% of canines, 10.17% of premolars and 10.85% of molars. The prevalence of the different degrees of dental wear was similar in males and females (P > 0.05). Conclusion: The modified TWI seems to be an effective tool for use in broad epidemiological surveys, due to easier calibration and high reproducibility rates. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the impact of treatment for Enamel-Dentin Fracture (EDF) on the daily activities of adolescents. This was a case-control study (1:4). The case group was composed of 40 adolescents from 11 to 17 years of age, presenting definitive restoration treatment for EDF for over 6 months. The control group was made up of 160 adolescents with no history of dental trauma and belonging to the circle of friends of the participants of the case group, matched by gender, age, and socioeconomic level. The outcome variable ‘impact’ was assessed through the Oral Impact on Daily Performances (OIDP). The independent variables were collected for being of interest to the study (dental trauma) or for acting as potential confounding factors (malocclusion, decay, and mother's education). Descriptive, univariate, simple and multiple logistic regression analyses were performed. Among the cases, the impact prevalence was 40.0%, whereas among the controls it was 16.9%. The more affected daily activities were showing the teeth (18.0%), eating (6.5%), speaking (2.0%), and cleaning the mouth (0.5%). The odds ratio of adolescents treated for EDF of presenting an impact on daily activities was 3.3 times (confidence interval 95%: 1.4–7.7) greater than among adolescents without dental trauma, controlling for mother's education, decay and the presence of malocclusion. Adolescents whose teeth have been esthetically treated for EDFs run a greater risk of presenting OIDP when compared to adolescents that have never suffered dental injuries. [ABSTRACT FROM AUTHOR]

Despite fluoride (F) use in caries prevention, not much is known about its effects on tooth quality. This study evaluated the effect of tooth F concentration ([F]) on selected dentin structural and mechanical properties. Third molars ( n = 136) from Toronto, which has 1 part per million (p.p.m.) water [F], Montreal (0.2 p.p.m. water [F]), and Fortaleza (Brazil) (0.7 p.p.m. water [F]), were analyzed for [F], dental fluorosis (DF) severity, ultrasound velocity, and dentin tubule size and density. The enamel [F] was found to vary between 32 and 940 p.p.m., the dentin [F] was found to vary between 110 and 860 p.p.m., while the DF severity varied between TF0 and TF4. The enamel [F] showed no correlation with dentin [F], DF severity, ultrasound velocity, dentin tubule size or density. The dentin [F] correlated with DF severity, dentin tubule size, and ultrasound velocity. DF severity showed a correlation with dentin [F] and ultrasound velocity. It was concluded that dentin [F] is an indicator of dentin structural properties (dentin tubule size and ultrasound velocity), while DF severity is an indicator of dentin mechanical properties (ultrasound velocity). [ABSTRACT FROM AUTHOR]

Objective To evaluate the microhardness of dentine underlying glass ionomer restorations made with Atraumatic Restorative Treatment.Design An experimental single-centre study.Setting University Department, Brazil, 2001.Materials and Methods Sixteen children were selected showing primary molars containing carious cavities (n=29), which were restored using Fugi IX. Subsequently, some teeth were extracted respecting Nolla stage 7 or 8 of the permanent successor, and categorised according to the post-restoration time in the mouth: G1 (baseline, immediate extraction), G2 (30 days), G3 (90 days) and G4 (180 days). Four teeth were excluded because they were not in time of normal exfoliation. The 25 extracted teeth were resin embedded, sectioned mesiodistally and prepared metallographically. Knoop microhardness analysis (Micromet 2003; 10g for 1.5 sec.) produced identations in three areas of dentine: Zone 1 (just below the restoration), Zone 3 (as close as possible to the pulp) and Zone 2 (intermediate region between 1 and 3). Non-parametric statistical tests were done — at a significance level of 5%.Results Four teeth were excluded. No significant difference was noted among the zones, inside the groups. Zones 1 and 2 showed a considerable increase of microhardness according to the time, except for Group 3 (p>0.05).Conclusion Although microhardness had increased, it was not sufficiently equal to the microhardness of the healthy dentine, regardless of the depth evaluated. [ABSTRACT FROM AUTHOR]