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OBJECTIVES: This study aimed at comparing the microtensile bond strength (MTBS) and interfacial adaptation of a modern self-curing and a light-curing restorative bulk-fill composite to a conventional composite applied with the layering technique. METHODS: Forty-eight occlusal cavities were divided in three main groups (16/group) based on tested materials: (i) STELA, bulk-fill self-curing restorative (STELA, SDI Ltd.); (ii) 3 M-BULK, bulk-fill composite (Filtek One Bulk-Fill, 3 M Oral Care); and (iii) 3 M-CTR, a conventional composite (Filtek Supreme XTE, 3 M Oral Care). These were used in combination with their adhesives in self-etch (SE) or etch-and-rinse (ER) mode. Specimens stored in artificial saliva (24 h or 12 months) were evaluated for MTBS and fractography. The interfacial analysis was performed through confocal microscopy. ANOVA and Fisher's LSD post hoc tests were performed with a level of significance of 5%. RESULTS: All the tested materials applied in ER mode presented (24 h) greater bond strength than in SE mode. Although all materials showed a significant drop in the bond strength after prolonged storage, STELA showed the highest bonding performance and interfaces with few gaps. 3 M-BULK had the lowest bond strength and an interface with several voids and gaps. CONCLUSIONS: All materials were affected by interface degradation and bonding reduction over prolonged aging. However, their use in combination with adhesives applied in ER mode may offer greater immediate bonding performance. CLINICAL RELEVANCE: The use of restorative light-curing bulk-fill composites may generate gaps at the bonding interface and voids. STELA may represent a suitable alternative to avoid such issues.

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OBJECTIVES: This study aimed to evaluate the adhesive properties in dentine after the application of silver diamine fluoride (SDF) on carious dentine lesions immediately and after 2 years of water storage. METHODS: 96 human molars used were subjected to artificial dentine caries production, and then randomly divided into 12 experimental groups according to 1. application of an SDF solution (carious dentine lesion without SDF treatment [control], with 12 % silver diamine fluoride [SDF 12 %] or 38 % silver diamine fluoride [SDF 38 %]); 2. Universal adhesives (Clearfil Universal Bond Quick [CUQ] and Single Bond Universal [SBU]); 3. adhesive strategy (etch-and-rinse [ER] and self-etch [SE]). After restoration, the specimens were sectioned and submitted to the microtensile bond strength test (µTBS) and energy-dispersive X-ray spectrometry analysis (SEM/EDX). All tests were performed immediately and after 2 years of water storage. Data from the µTBS were analyzed using four-way ANOVA and Tukey's test (α = 0.05). RESULTS: Only the interaction of factors 'SDF' vs 'time' was significant (p = 0.03). After 2 years of storage, the groups where SDF was applied showed higher µTBS values compared to the control group. No significant decrease in µTBS values was observed for SBU when comparing immediate and 2-year results, but a significant reduction in µTBS values was observed after 2 years for CUQ. CONCLUSION: Independent of the adhesive strategy, the use of SDF may be a promising alternative to maintain the bonding of universal adhesives to carious dentinal lesions. CLINICAL SIGNIFICANCE: This study may clarify and support clinicians regarding the longevity of resin-based restoration in caries-affected dentine treated with silver diamine fluoride.

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More than three decades have passed since the publication of Lamendin et al.'s proposal in 1992. Over this time, numerous investigations have been conducted to assess the applicability of the technique in different populations with acceptable results in terms of estimation errors. The proposal by Lamendin and colleagues remains relevant today, and has made a significant contribution to adult age-at-death estimation due to its simplicity, repeatability, replicability, and high performance. Indeed, significant progress towards systematizing and strengthening the procedure has been reported in the published literature. One noteworthy advancement is the development of an international database that supports the use of Bayesian statistics for age-at-death estimation. This resource plays a crucial role in standardizing the methodology and improving the reliability for obtaining more reliable results on a global scale. The aim of this study is to investigate the historical evolution of the technique, to assess the accuracy of the results obtained by different analytic procedures, and to explore its impact in forensic applications through a systematic analysis of the specialized literature on this field. The current state of research indicates that this type of methodological research is an ongoing process, far from being completed. Many questions and challenges that require further attention to address effectively these issues remain unanswered, such as the development of non-linear regressions and probabilistic approaches, the deepening of procedures that improve global approximations, and the intensification of research focused on achieving more accurate estimations among individuals over 70 years-old. However, studies generally agree that the Lamendin technique works well for individuals between the ages of 30-60 years. It is still in force today, although the method has been significantly perfected. Despite the degree of research development in this area, further efforts are needed to improve the understanding and performance of these kinds of procedures. This will ultimately lead to an improvement in the accuracy and reliability of forensic investigation results worldwide.

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Objective: The aim of this study was to determine if SEM used with imaging software could be used to quantitatively determine the extent of dentine roughness due to tooth-brushing. Material and methods: Flat, polished dentine surfaces were subjected to 25,000 cycles of simulated tooth-brushing at 2 strokes per second with a load of 200 g. At the end of the brushing cycle, dentine surfaces were first assessed using profilometry and then subjected to SEM analysis. Ra (average roughness) readings were obtained for profilometric assessment. Using imaging software, the horizontal distance between adjacent characteristic grooves noted on micrographs was measured, ensuring that the middle of each crest of the associated groove was used as the reference point, the Crest-to-Crest distance (C-C distance). These two parameters were examined statistically for correlation. Results: When Spearman Rank tests were utilized the correlation between average Ra and crest to crest measurements was 0.709 (p <0.01). The Bland Altman plot, however, showed poor agreement between the two test parameters. Conclusion: Further work is needed to validate the use of this methodology in the quantitative assessment of tooth surface loss due to abrasion (AU)

Objetivo: O objetivo deste estudo foi determinar se o MEV usado com software de imagem poderia ser usado para determinar quantitativamente a extensão da rugosidade da dentina devido à escovação dentária. Material e Métodos: Superfícies dentinárias planas e polidas foram submetidas a 25.000 ciclos de escovação dentária simulada a 2 movimentos por segundo com uma carga de 200g. No final do ciclo de escovação, as superfícies dentinárias foram primeiro avaliadas por perfilometria e depois submetidas à análise MEV. Leituras de Ra (rugosidade média) foram obtidas para avaliação perfilométrica. Utilizando um software de imagem, foi medida a distância horizontal entre sulcos característicos adjacentes observados nas micrografias, garantindo que o meio de cada crista do sulco associado fosse usado como ponto de referência, a distância crista a crista (distância CC). Esses dois parâmetros foram examinados estatisticamente para correlação. Resultados: Quando foram utilizados os testes de Spearman Rank, a correlação entre a média de Ra e as medidas de crista a crista foi de 0,709 (p<0,01). O gráfico de Bland Altman, no entanto, mostrou fraca concordância entre os dois parâmetros de teste. Conclusão: Mais trabalhos são necessários para validar o uso desta metodologia na avaliação quantitativa da perda da superfície dentária devido à abrasão(AU)

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

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The objective of this study is to evaluate the effect of 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) and chitosan (CHI) on the adhesive interface of resin cements to root dentine. Forty-five upper canines were sectioned, endodontically treated, prepared and divided into three groups according to dentine treatment (distilled water-DW, CHI 0.2% and EDC 0.5) and in three subgroups according to resin cement: RelyX ARC, Panavia F 2.0 or RelyX U200. Slices were obtained, with five slices of each third submitted to the analysis of the adaptation of the adhesive interface through scores and the perimeter with gaps in confocal laser scanning microscopy and one slice of each third later evaluated qualitatively in scanning electron microscopy. The results were analyzed using with Kruskal-Wallis and Spearman correlation tests. There was no difference in adaptation for the different resin cements (p = .438). EDC presented better adaptation when compared to the groups treated with DW and CHI (p < .001), while the CHI and DW presented similar adaptation values (p = .365). No difference was observed in the perimeter referring to the gap areas for the different resin cements (p = .510). EDC showed a lower percentage of perimeters with gaps when compared to CHI (p < .001), with the percentage of perimeter with gaps of teeth treated with CHI being lower than DW (p < .001). A positive correlation coefficient equal to 0.763 was obtained between the perimeter with gaps and the adaptation data of the adhesive interface (p < .001). EDC resulted in better adaptation of the adhesive interface and a lower percentage of perimeters with gaps compared to chitosan.

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We evaluated the effects of dentine biomodification after pre-treatment with two sulphonamide carbonic anhydrase inhibitors (CAIs) of the N-[4-sulphamoylphenethylcarbamoyl]benzenesulphonamide type, investigating matrix metalloproteases activity, resin-dentine micro tensile bond strength, dentine surface wettability, and antimicrobial activities. Ninety-five sound-extracted human molars were selected for the study. Inhibitory effects were evaluated by gelatinase and collagenase activity tests and collagen degradation FT-IR spectroscopic analysis. Pre-treatment with the two CAIs kept the micro tensile values after 12 months of storage (32.23 ± 5.95) and cariogenic challenge (34.13 ± 2.71) similar to the initial, pre-treatment values (33.56 ± 4.34). A decreased Streptococcus mutans biofilm formation on dentine surfaces and antibacterial activity against planktonic bacteria were observed after CAI treatment. Dentine pre-treatment with sulphonamide CAIs maintained adhesion strength stability, allowed better dentine wettability, maintained matrix collagen, and showed anti-S. mutans activity.

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Objetivo: La reabsorción dentinaria interna es un pro- ceso causado por la actividad odontoclástica asociada princi- palmente a la inflamación pulpar crónica y/o traumatismos, y se caracteriza por la pérdida progresiva de tejido dentinario y la posible invasión al cemento. El presente informe describe el diagnóstico y tratamiento de un molar inferior que presentó un cuadro sintomático de reabsorción dentinaria interna. Caso clínico: Un paciente de 38 años fue derivado a la consulta por presentar una zona de reabsorción interna en un segundo molar inferior. Durante el examen clínico y ra- diográfico se tomó una radiografía preoperatoria periapical con radiovisiógrafo en la que se observó la presencia de un área compatible con el diagnóstico de reabsorción dentinaria interna, el que fue posteriormente confirmado por medio de una tomografía computada de haz cónico. La imagen de la lesión se presentó como una zona radiolúcida deformante de bordes nítidos, localizada a nivel de la cámara pulpar. El tra- tamiento consistió en la extirpación de la pulpa coronaria y de la instrumentación, desinfección y obturación de los conduc- tos radiculares y la cavidad de acceso. En el control clínico y radiográfico realizado luego de 3 años se observó que el paciente estaba asintomático y las estructuras perirradiculares se encontraban dentro de los límites normales. La observación histológica del material removido de la cámara pulpar reveló la presencia de un tejido granulomatoso con numerosos vasos sanguíneos y escasos focos micro hemorrágicos. Hasta el momento, el tratamiento endodóntico es el pro- cedimiento indicado para el tratamiento de la reabsorción dentinaria interna. Se destaca la importancia de la tomografía computada de haz cónico para el diagnóstico y tratamiento temprano de las reabsorciones dentinarias internas a efectos de contar con un pronóstico favorable (AU)

Aim: Internal dentine resorption is aprocess caused by odontoclastic activity, mainly associated with chronic pulpal inflammation and/or trauma, and it'scharacterized by a pro- gressive loss of dentine tissue and the possible invasion of the cementum. This report describes the diagnosis and treatment of a lower molar that presented a symptomatic case of inter- nal dentine resorption. Clinical case: A 38-years old patient was referred to the office because of presenting an area of internal resorption in a lower second molar. During clinical and radiographic exam- ination, a periapical preoperative radiograph with radiovisio- graph was taken, in which the presence of an area compatible with the diagnosis of internal dentine resorption was observed, which was later confirmed by a cone-beam computed tomog- raphy.The image of the lesion was presented as a deforming radiolucent area with sharp edges, located at pulp chamber level. Treatment consisted of the removal of the coronary pulp and the instrumentation, disinfection and filling of the root ca- nals and the access cavity. In the clinical and radiographic control carried out 3 years after procedure, it was observed that the patient was asymptomatic and the periradicular struc- tures were within normal limits. The histological observation of the removed material from the pulp chamber revealed the presence of a granulomatous tissue with numerous blood ves- sels and scarce micro hemorrhagic focus. Until now, the endodontic treatment is the indicated pro- cedure to treat internal dentine resorption. It is necessary to highlight the importance of the cone-beam computerized to- mography for the early diagnosis and treatment of internal dentine resorptions in order to have a favorable outlook (AU)

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AIM: To evaluate the effects of progressive root canal enlargements on the unprepared surface area and remaining dentine thickness of three-rooted maxillary first premolars with different root configurations. METHODOLOGY: Thirty three-rooted maxillary first premolars with three root configurations (n = 10) were selected and scanned in a micro-CT device. The root canals were sequentially enlarged with rotary instruments sizes 30.02 (step 1), 30.04 (step 2) and 30.06 (step 3). After each step, a new scan was taken. Analysed parameters included morphometric measurements (length, volume and surface area), number of static voxels and minimal dentine thickness. Statistical analyses were performed with one-way anova post hoc Tukey tests and paired sample t-test at a significance level of 5%. RESULTS: No statistical differences were observed amongst groups regarding the morphometric parameters and static voxels (p > .05). The minimal dentine thickness of the distobuccal root significantly changed depending on the root configuration (p < .05), whilst no differences were observed in the other roots (p > .05). A great variation in the position of the minimal dentine thickness was observed after preparation. Overall, mean percentage reduction in dentine thickness was higher in the buccal roots than in the palatal root (p < .05). In the mesiobuccal and distobuccal root, the number of slices with minimal dentine thickness lower than 0.05 mm increases 2 to 3 times and 3 to 4 times, respectively, from steps 1 to 3. CONCLUSIONS: Instruments sizes 30.02 and 30.04 can be safely and effectively used to enlarge the buccal and palatal canals of three-rooted maxillary first premolars.

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O presente trabalho tem como objetivo realizar uma revisão de literatura e discutir os mais atuais conceitos sobre abordagem conservadora de lesões cariosas profundas, facilitando o manejo clínico. Para que essa abordagem conservadora seja implementada, é imprescindível que se conheça a composição estrutural e funcional do biofilme para, assim, entender a evolução da doença cárie que acomete a estrutura dentária. No entanto, quando se trata de um dente com lesão de cárie ativa com grande comprometimento de esmalte e dentina, procedimentos operatórios mais invasivos e restauradores podem ser necessários, mesmo que fundamentados na maior preservação possível de estrutura dentária. As evidências mais atuais encontradas na literatura recomendam a remoção seletiva do tecido cariado que consiste na dentina infectada, ou seja, clinicamente amolecida, e restauração definitiva na mesma sessão. Portanto, desde que o dente apresente vitalidade pulpar clinicamente confirmada, acredita-se que a preservação estratégica da dentina, poderá aumentar as chances de sucesso no tratamento, evitando possível exposição da polpa dentária. Adicionalmente, ao optar por práticas conservadoras no contexto da Odontologia de mínima intervenção, resultará em um significativo aumento na longevidade das restaurações sempre associando promoção de saúde ao paciente(AU)

This paper aims to conduct a literature review and discuss the most current concepts on conservative approach to deep carious lesions in permanent posterior teeth, facilitating clinical management. For this conservative approach to be implemented, it is essential to know the structural and functional composition of the biofilm in order to understand the evolution of the caries disease that affects the dental structure. However, when it comes to a tooth with an active caries lesion with major enamel and dentin compromise, more invasive and restorative surgical procedures may be necessary, even if based on the greatest possible preservation of the dental structure. The most current findings in the literature recommend the selective removal of carious tissue consisting of infected dentin, that is, clinically softened, and definitive restoration in the same session. Therefore, as long as the tooth has clinically confirmed pulp vitality, it is believed that the strategic preservation of dentin may increase the chances of successful treatment, avoiding possible exposure of the dental pulp. Additionally, when opting for conservative practices in the context of Minimally Invasive Dentistry, it will result in a significant increase in the longevity of restorations, always associating health promotion to the patient(AU)

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Objetivo: Describir el tratamiento de un paciente que pre- sentó un incisivo superior permanente con exposición pulpar y desarrollo radicular incompleto utilizando Biodentine como material para la protección pulpar directa. Caso clínico: Un paciente de 9 años fue derivado para la evaluación y el tratamiento del diente 11. El examen clínico y radiográfico reveló la presencia de una fractura amelodentinaria, con exposición pulpar y desarrollo radicular incompleto. Luego de lavar y desinfectar el área de la fractura, se protegió la pulpa expuesta con Biodentine y se restauró la cavidad. El paciente fue citado para control a los 18 y 25 meses. En los controles se comprobó que el diente se mantuvo asintomático y funcional. Luego de 25 meses, el examen clínico y radiográfico confirmó la presencia de pulpa vital y el completo desarrollo del remanente radicular. Los resultados obtenidos en el presente caso clínico sugieren que el empleo de Biodentine puede ser considerado como una valiosa alternativa para la protección de la pulpa ex- puesta en dientes con desarrollo radicular incompleto (AU)

Aim: To describe the treatment of a patient that presented a permanent maxillary central incisor with pulp exposure and incomplete root formation, using Biodoentine as the material for direct pulp protection. Clinical case A 9-year-old male patient was referred for evaluation and treatment of tooth 11. The clinical and radio-graphic examination revealed the presence of a dentinoe- namel fracture, with pulp exposure and incomplete root for- mation. After cleaning and disinfecting the area, the exposed pulp was protected with Biodentine and the cavity was re- stored. The patient was scheduled for control after 18 and 25 months. In these evaluations, it was confirmed that the tooth remained asymptomatic and functional. After 25 months, the clinical and radiographic examination showed the presence of vital pulp and a completed development of the root. The obtained results of this clinical case suggest that Biodentine can be considered a valuable alternative for pulp capping in teeth with incomplete root formation (AU)

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OBJECTIVES: Evaluate the ability of current ion-releasing materials to remineralise bacteria-driven artificial caries lesions. MATERIALS AND METHODS: Standardised class I cavities were obtained in 60 extracted human molars. Specimens underwent a microbiological cariogenic protocol (28 days) to generate artificial caries lesions and then were randomly divided into four restorative groups: adhesive + composite (negative control); glass ionomer cement (GIC); calcium silicate cement (MTA); and resin-modified calcium silicate cement (RMTA). Microhardness analysis (ΔKHN) was performed on 40 specimens (10/group, t = 30 days, 45 days, 60 days in artificial saliva, AS). Micro-CT scans were acquired (3/group, t = 0 days, 30 days, and 90 days in AS). Confocal microscopy was employed for interfacial ultra-morphology analysis (2/group, t = 0 days and 60 days in AS). Additional specimens were prepared and processed for scanning electron microscopy (SEM) and FTIR (n = 3/group + control) to analyse the ability of the tested materials to induce apatite formation on totally demineralised dentine discs (60 days in AS). Statistical analyses were performed with a significance level of 5%. RESULTS: Adhesive + composite specimens showed the lowest ΔKHN values and the presence of gaps at the interface when assessed through micro-CT even after storage in AS. Conversely, all the tested ion-releasing materials presented an increase in ΔKHN after storage (p < 0.05), while MTA best reduced the demineralised artificial carious lesions gap at the interface. MTA and RMTA also showed apatite deposition on totally demineralised dentine surfaces (SEM and FTIR). CONCLUSIONS: All tested ion-releasing materials expressed mineral precipitation in demineralised dentine. Additionally, calcium silicate-based materials induced apatite precipitation and hardness recovery of artificial carious dentine lesions over time. CLINICAL RELEVANCE: Current ion-releasing materials can induce remineralisation of carious dentine. MTA shows enhanced ability of nucleation/precipitation of hydroxyapatite compared to RMTA and GIC, which may be more appropriate to recover severe mineral-depleted dentine.

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La hipersensibilidad de la dentina surge ante la exposición de esta y en respuesta a estímulos de diverso tipo, fundamentalmente de origen térmico, evaporativo, táctil, osmótico o químico. Se realizó una investigación abocada a caracterizar la hipersensibilidad dental de pacientes atendidos en consulta de odontología y la respuesta a determinado dentífrico utilizado. En el análisis de estimulación dental se tomaron 308 mediciones de la sensibilidad dental para todos los participantes (n=22), con 7 factores de tiempo (T0 antes del uso del producto, T3 días, T5 días, T8 días, T22 días y T29 días después del uso del dentífrico). Se realizó la prueba paramétrica regresión lineal simple para identificar la tendencia y el ajuste de los datos, al considerar dichas variables como una serie temporal. Se utilizaron 22 tratamientos. Casi el 91,0% expreso que el dentífrico había cumplido sus expectativas, fundamentalmente por la reducción de la hipersensibilidad a corto plazo, mientras que aproximadamente 91,0% de los casos afirmó que compraría el dentífrico (20 casos, IC 95%: 72,2% y 97,5%), respectivamente(AU)

Dentin hypersensitivity arises when exposed to it and in response to various types of stimuli, mainly of thermal, tactile evaporative, osmotic or chemical origin. An investigation was carried out aimed at characterizing the dental hypersensitivity of patients seen in the dental office and the response to a certain toothpaste used. In the dental stimulation analysis, 308 measurements of tooth sensitivity were taken for all participants (n = 22), with 7 time factors (T0 before use of the product, T3 days, T5 days, T8 days, T22 days and T29 days after using the toothpaste). The simple linear regression parametric test was performed to identify the trend and the fit of the data, considering these variables as a time series. 22 treatments were used. Almost 91.0% believed that the toothpaste had met their expectations, mainly due to the reduction in hypersensitivity in the short term, while approximately 91.0% of the cases stated that they would buy the toothpaste (20 cases, 95% CI: 72 , 2% and 97.5%), respectively(AU)

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The present study evaluated the effect of high-fluoride dentifrice on dentine demineralization and bacterial composition in a multispecies biofilm model in vitro. A seven-organism bacterial consortium was grown on bovine dentine discs in a high-throughput active attachment model. The biofilms were submitted twice per day to the following dentifrices treatments: 5,000 ppm F, 1,100 ppm F, with placebo as a negative control. After 5 days of biofilm growth, dentine samples were assessed by transversal microradiography, the biofilm was collected for bacterial counts and the pH of the media was determined. Lower integrated mineral loss values were observed when 5,000 ppm F-treatment was used compared to the other treatments. Overall microbiological counts decreased with increasing F-concentration as well the pH of the media throughout the experiment. The 5,000 ppm F-treatment caused a shift in microbial composition and reduced dentine demineralization in the in-vitro experimental model.

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AIM: To describe the radicular dentine thickness in mandibular first premolars presenting C-shaped root canals, to identify the canal walls with less thickness as potential danger zones. In addition, to describe the internal and external anatomical characteristics of these teeth and associate them with the dentine thickness. METHODOLOGY: A total of 70 mandibular first premolars presenting C-shaped root canals were examined. Their internal morphology was analysed using Vertucci's and Fan's criteria, and their external morphology was analysed using the ASUDAS score. Besides, the dentine thickness around the root canals was two/three-dimensionally determined at five root planes and quantified in the distal and the mesial aspects. RESULTS: According to Fan's, ASUDAS, and Vertucci's classifications, the most common canal configurations were category C3, grade 3, and type V, respectively. In Vertucci's type III anatomy, the mesial root wall of the lingual canal showed significantly less dentine thickness than the distal wall in the middle plane (p = .031). Similarly, in Vertucci's type V anatomy, significantly less dentine thickness was observed in the mesial root wall of the buccal and lingual canals in the middle plane (p < .001) and the buccal canal in the middle-apical plane (p = .014) than the distal root wall of these canals. In teeth with ASUDAS grade 3 and 4 scores, significantly less dentine thickness was observed in the mesial in comparison with the distal root wall of these canals. These differences were demonstrated in the middle and middle-apical planes (p < .001) of grade 3 teeth and the middle-apical plane (p < .001) of grade 4 teeth. In these root planes, the Ver1-AS3 and VerV-AS3 combinations presented a 4-times greater risk of presenting walls with a critical dentine thickness of 0.6 mm (odds ratio [OR] = 4, p = .025) than the combinations Ver1-AS2, VerV-AS2, VerV-AS4, and VerIII-AS3. CONCLUSIONS: The root canal system configuration of mandibular first premolars with C-shaped canals showed a wide range of anatomical variations. The lowest dentine thickness was located in the mesial wall of the canals in the middle and apical root thirds of Vertucci's type III and V anatomies and in teeth with deep radicular grooves scored as ASUDAS grades 3 and 4. In the middle and middle-apical planes, the presence of the combinations Ver1-AS3 and VerV-AS3 showed a high risk of presenting a critical dentine thickness of 0.6 mm. Therefore, these root canal walls with less dentine thickness represent potential instrumentation danger zones in mandibular first premolars with C-shaped canals.

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OBJECTIVES: This study aimed at evaluating the microtensile bond strength (µTBS) and the resin-dentine ultramorphology (24 h and 10 months ageing) of contemporary universal adhesives applied in self-etch (SE) or etch-and-rinse (ER) mode. MATERIALS AND METHODS: Sixty-four sound human molars were collected and randomly allocated in 4 main experimental groups (n = 16) according to the adhesive system employed and subsequently divided into two subgroups depending on their application mode SE or ER (n = 8): ZipBond X (ZBX-SE; ZBX-ER), Prime and Bond Active (PBA-SE; PBA-ER), Clearfil Universal Bond Quick (CBQ-SE; CBQ-ER) or Scotchbond Universal (SCH-SE; SCH-ER). The specimens were cut into sticks with a cross-sectional area of approximately 0.9 mm2 and subjected to µTBS testing at 24 h or after 10 months of ageing in artificial saliva (AS). Five representative fractured specimens from each group were analysed using field-emission scanning electron microscopy (FE-SEM). Resin-dentine slabs (Ø 0.9mm2) from each experimental group were immersed in Rhodamine B and subsequently analysed using confocal microscopy analysis (CLSM). The µTBS results were analysed using a two-way ANOVA and Newman-Keuls multiple-comparison test (α = 0.05). RESULTS: ZBX, PBA and SCH exhibited greater µTBS values than CQB at 24 h in both SE and ER modes (p < 0.05). CQB showed a significant decrease in µTBS values after ageing both when used in SE and ER mode (p < 0.05). ZBX-ER exhibited no significant differences in the µTBS test after ageing (p > 0.05), while a significant drop in µTBS was seen in SCH-ER and APB-ER after 10-month ageing (p < 0.05). Clear signs of degradation were evident in the resin-dentine interface created with CQB regardless of the application mode or the ageing time. In APB-ER and SCH-ER groups, such signs of degradation were evident after ageing in AS. ZBX showed slight dye infiltration both when used in ER and SE mode. CONCLUSIONS: The long-term bonding performance of modern universal adhesives is usually influenced by the adhesive strategy employed; self-etching application should be prioritised during dentine bonding. Moreover, the use of shortened bonding protocols may compromise the quality of the resin-dentine interface and the bonding performance of most modern universal adhesives. CLINICAL RELEVANCE: The use of etch-and-rinse bonding procedures, as well as "shortened" application protocols should be eluded when using modern universal adhesives in dentine. However, new generation universal adhesives based on innovative chemical formulations may probably allow clinicians to achieve long-term bonding performance with such simplified system also when employed in ER mode.

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AIM: To evaluate the shaping ability of several heat-treated nickel-titanium systems used to prepare root canals with moderate and severe curvature, in extracted mandibular molars, by micro-computed tomography, considering their variation in kinematics and design. METHODOLOGY: Curved-mesial roots of mandibular molars were randomly selected and assigned into 4 balanced experimental groups (n = 10), established by determining homogeneous 3D parameters of volume and surface area: R-Motion (RM) size 30, 0.04 taper (RM; FKG Dentaire), Reciproc Blue (RCB) size 25, 0.08 taper (RCB; VDW GmbH), HyFlex CM (HFX) size 30, 0.04 taper (HFX; Coltène Whaledent) and XP-endo Shaper size (XPS) 30, 0.01 taper (XPS; FKG Dentaire). The volume of irrigation was established at 10 ml of 2.5% NaOCl. Throughout the entire root canal preparation procedures, the samples were fixed in a vice submerged in a container with water monitored at 37°C. Dimensional cross-sectional measures of area, perimeter, roundness, major/minor diameters and 3-dimensional (volume, surface area, structure model index - SMI) parameters as well as the smallest dentine thickness along the cervical and middle root thirds were evaluated by micro-CT. Data were analysed using analysis of variance and post hoc Tukey tests (α = 5%). RESULTS: Reciproc Blue and XPS had significantly greater mean increases in cross-sectional area measurements, only in the middle third, when compared with RM and HFX (p < .05). RM, RCB and XPS had a similar increase in measurements of length and width of perimeter (p > .05), and HFX had significantly lower mean increases in perimeter values only when compared with XPS (p < .05). RCB and XPS had significantly greater mean increases in volume when compared with RM and HFX (p < .05). RM had a significantly lower difference in SMI after preparation, compared with RCB, HFX and XPS (p < .05). The smallest dentine thickness was observed after the use of RCB (p < .05), in the danger and safety zones. CONCLUSIONS: XP-endo Shaper and RM had a shaping ability similar to that of instruments with larger tapers, achieved with less dentine removal in danger and safe zones in curved-mesial canals of extracted molar teeth treated on a laboratory benchtop.

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AIM: To evaluate the influence of traditional and conservative access cavity preparations on the remaining dentine thickness in the coronal third of mesial canals of extracted mandibular molars prepared with reciprocating instruments using micro-computed tomography as the analytical tool. METHODOLOGY: Seventy extracted mandibular molars were scanned at a pixel size of 19 µm. From this initial sample, 20 teeth were selected, pair-matched and distributed into two groups (n = 10) according to the access cavity preparation: traditional (TradAC) or conservative (ConsAC). The root canals were sequentially enlarged with Reciproc Blue R25 (size 25, 0.08v taper) and R40 (size 40, 0.06v taper) instruments. A new scan was performed and the postoperative stacks were coregistered with their respective preoperative datasets. A colour-coded cross sections of the roots were created and used to identify and measure the smallest dentine thickness related to both MB and ML canals at 1.0-mm intervals from the furcation level of up to 5 mm in the apical direction, in both mesial and distal aspects of the roots, before and after preparation. The statistical analyses were performed with paired-samples t-test, independent-samples Student T-test and Chi-Square test with a significance level of 5%. RESULTS: At all levels of both groups, dentine thickness before preparation was greater than after preparation (p < .05). No difference in the percentage of dentine reduction was observed between TradAC and ConsAC groups (p > .05), but a significantly greater reduction was observed to the distal aspect of the roots (p < .05). After root canal preparation, dentine thinner than 0.5 mm was observed mostly along the distal aspect of the root (10% to 15%) of the MB and ML canals, with no influence of the access cavity type on its incidence to either mesial (X2  = 1.66; p = .2) or distal (X2  = 0.40; p = .5) directions. In the TradAC group, dentine thickness in most slices was greater than 1.0 mm after preparation (n = 124) whilst, in the ConsAC, it ranged from 0.5 to 1.0 mm (n = 136). CONCLUSION: Traditional or conservative access cavity preparation in extracted mandibular molars did not influence the remaining dentine thickness in the coronal third of mesial canals enlarged with thermomechanically treated nickel-titanium reciprocating instruments.

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OBJECTIVES: This two-arm, parallel-group, tooth-randomised, controlled noninferiority clinical trial aimed to compare survival rates between the sealing and restoring of cavitated occlusal carious lesions in dentine [International Caries Detection and Assessment System (ICDAS) 5] of deciduous molars using resin-modified glass-ionomer cement (RMGIC) and to assess caries progression radiographically. MATERIALS AND METHODS: A total of 68 molars with ICDAS 5 occlusal lesions were randomly allocated into two groups, a sealing group (n = 31), in which RMGIC was placed directly over the carious lesion, and a restoration group (n = 37), in which a restoration with the same material was placed after selective caries removal. During the baseline and follow-up visits, dental caries was registered and caries activity was assessed according to a visuotactile criterion. At baseline, patient caries status (dmf-t) and cavity depth and extent (mesiodistal and buccolingual) were measured before RMGIC placement. An independent and blinded examiner evaluated the treated teeth using the USPHS criteria after one and two years. Standardised interproximal radiographs were taken for caries progression assessments. RESULTS: During the follow-up period, no lesion progression was observed radiographically. After one year (n = 60; 27 sealed and 33 restored) and two years (n = 48; 23 sealed and 25 restored) of follow-up, the treatment success rates were 78.8% and 76.0% in the restoration group and 59.3% and 47.8% in the sealing group, respectively. Multivariate Cox regression showed that lesions smaller than 2 mm in the mesiodistal extent were less prone to fail after one year (p = 0.03). However, survival curves (log-rank test) were statistically significantly different only after two years (p < 0.001). CONCLUSIONS: Sealing ICDAS 5 occlusal lesions of deciduous molars using RMGIC achieved lower survival rates than restorations. Both sealing and restoration effectively arrested caries progression for two years. Clinical relevance Sealing dentine carious lesions can be effective for treating lesions involving the inner and outer half of the dentine. Ultraconservative treatments can arrest carious lesions presenting obvious cavitation in primary molars. TRIAL REGISTRATION: ReBEC Register no. RBR-225n35.

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Objective: This randomized controlled trial aimed to compare nanohydroxyapatite with fluoride on managing post ultrasonic scaling Dentine hypersensitivity (DH). Material and Methods: Thirty patients (aged 20-50 years) with post ultrasonic-scaling DH were included in this study. The sample was randomly divided into three equal groups of 60 teeth each: the first group received nanohydroxyapatite material, the second group received fluoride material and the third group received sterile water as a placebo (controls). The materials were applied once for each patient. All patients were instructed to rate the level of pain before treatment, and after 1 hour, 24 hours, 2 weeks and 1 month on the numerical rating scale (NRS). The Kruskal-Wallis test, Mann-Whitney tests, linear regression analysis were used for the statistical analysis. Significance level was set at 0.05. Results: Both nanohydroxyapatite and fluoride were successful in reducing pain associated with DH when compared with the placebo in subsequent follow-ups (p < 0.05). However, one-hour and one-day post application, nanohydroxyapatite could reduce hypersensitivity pain moreeffectively than fluoride (p < 0.05). Conclusion: Nanohydroxyapatite material was found to besignificantly more effective in reducing the DH that followed ultrasonic scaling one-hour and one-day post application as compared to fluoride and sterile water. Both fluoride and nanohydroxyapatite had similar effect on DH after two-weeks and one-month after application. (AU)

Objetivo: Este ensaio clínico randomizado teve como objetivo comparar a nano-hidroxiapatita com o flúor no manejo da hipersensibilidade dentinária (HD) pós-raspagem ultrassônica. Material e Métodos: Trinta pacientes (com idades entre 20-50 anos) com HD pós-raspagem ultrassônica foram incluídos neste estudo. A amostra foi dividida aleatoriamente em três grupos iguais com 60 dentes cada: o primeiro grupo recebeu material de nano-hidroxiapatita, o segundo grupo recebeu material de flúor e o terceiro grupo recebeu água esterilizada como placebo (controle). Os materiais foram aplicados uma vez para cada paciente. Todos os pacientes foram instruídos a avaliar o nível de dor antes do tratamento, e após 1 hora, 24 horas, 2 semanas e 1 mês na escala de avaliação numérica (NRS). Os testes de Kruskal-Wallis, Mann-Whitney e análise de regressão linear foram usados para a análise estatística. O nível de significância foi estabelecido em 0,05. Resultados: Tanto a nano- hidroxiapatita quanto o flúor foram bem-sucedidos na redução da dor associada à HD quando comparados ao placebo em acompanhamentos subsequentes (p <0,05). No entanto, 1 hora e 1 dia após a aplicação, a nano-hidroxiapatita pode reduzir a dor de hipersensibilidade de forma mais eficaz do que o flúor (p <0,05). Conclusão: O material da nano-hidroxiapatita foi significativamente mais eficaz na redução da HD que se seguiu à raspagem ultrassônica, 1 hora e 1 dia após a aplicação, em comparação com o flúor e a água estéril. Tanto o flúor, quanto a nano-hidroxiapatita apresentou efeito semelhante na HD após 2 semanas e 1 mês após a aplicação (AU)

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