Search

Objectives: The objective of this study was to describe the knowledge, opinions and practices about the defective restoration (DR) management of French general dental practitioners (GDPs). Methods: A cross-sectional, online survey-based study was carried out amongst 378 GDPs - members of the dental practice-based research network in France (ReCOL). Bivariate comparisons were made using Fisher's exact test to assess the association of the respondent characteristics (age, gender…) with the decision to repair DRs, and responses to clinical cases. Results: The response rate was 82.9%. 50.4% of the respondents declared they at least sometimes consider DRs repair in their clinical practice instead of DRs total replacement. For the 89.8% who at least rarely repaired DRs, the main characteristic determining the therapeutic strategy was the defect size (71%, mainly inclined to repair small defects), followed by the defect type (marginal defect or crack for more than 60% of the respondents) and the material of initial restoration (composite for 63.5%). When shown clinical photographs illustrating DRs, most of respondents proposed a replacement with inlay/onlay or crown. Conclusions: This study indicates that a significant proportion of French GDPs do not make sufficient use of DR repair on a routine basis. A lack of knowledge of the concept seems to explain at least part of this situation. Collective and individual efforts from the profession are still needed to promote DR repair and therefore more often apply MinimalIntervention Dentistry. Clinical significance: This survey shows that MID is not yet sufficiently used in routine practice in France regarding DR management. Further efforts (continuing education toward MID, public funding revaluation for MID strategies…) are needed to help GDPs to implement MID into everyday practice.

The conventional radiotherapy protocol to treat head-and-neck cancer is usually followed by tooth-decay onset. Radiation impact on mineralized tooth structures is not well-understood. This systematic review aimed to collect the recorded effects of therapeutic radiation on tooth chemical, structural and mechanical properties, in relation with their means of investigation.Systematic search (January 01 2012 - September 30 2021) terms were "Radiotherapy", "Radiation effects", "Dental enamel", "Dentin", "Human" and "Radiotherapy" NOT "Laser".PubMed, DOSS and Embase databases were searched.Selected studies compared dental enamel, coronal and root dentin properties before and after in vitro or in vivo irradiation up to 80 Gy.The systematic search identified 353 different articles, with 28 satisfying inclusion criteria. Their reference lists provided two more. Twenty-two studies evaluated dental enamel evolution, nine assessed coronal dentin and eight concerned root dentin. Coronal and root dentin results indicate a major impact of the radiation on their organic matrix. Dental enamel's chemical properties are less modified. Enamel and root dentin's hardness are decreased by therapeutic radiation, but no consensus arises for coronal dentin.Our findings revealed some interesting information about enzymatic degradation mechanisms of dentin organic matrix and highlighted that dental hard-tissue characterization requires highly specific expertise in materials science. That scientific knowledge is necessary to design suitable protocols, adequately analyze the obtained data, and, thus, provide relevant conclusions.Better knowledge and understanding of the mechanisms involved in the degradation of enamel and dentin would enable development of new preventive and therapeutic methods for improved medical care of patients undergoing radiotherapy.

To evaluate in vitro the mechanical, biological, and polymerization behavior of a flowable bulk-fill composite with fibers as a dispersed phase.EverX Flow™ (GC Corporation) (EXF), one conventional bulk-fill composite (Filtek™ Bulk Fill Posterior Restorative, 3 M (FBF)), and one flowable bulk composite without fibers (SDR® flow+, Dentsply (SDR)) were tested. Samples were characterized in terms of flexural strength (ISO 4049), fracture toughness (ISO 20795-1), and Vickers hardness. Polymerization stress and volumetric shrinkage were evaluated. The in vitro biological assessment was achieved on cultured primary Human Gingival Fibroblast cells (HGF). The cell metabolic activity was evaluated using Alamar Blue assay at 1, 3, and 5 days of contact to the 3 tested composite extracts (ISO 10993) and cell morphology was evaluated by confocal microscopy. Data were submitted to One-Way analysis of variance (ANOVA) and independent t-test (α = 0.05).FBF showed statistically higher Vickers hardness and flexural modulus than EXF and SDR. However, EXF showed statistically higher KEXF had a significantly higher fracture toughness validating its potential use as a restorative material in stress bearing areas. EXF showed higher shrinkage stress values, and less cytotoxic effect. Fiber reinforced flowable composite is mainly indicated for deep and large cavities, signifying the importance for assessing its shrinkage stress and biological behavior.

The current study aimed to assess the topographical and physical properties of a minimally invasive implant (MagiCore®: MC®, InnosBioSurg, IBS) and to evaluate its biological behavior compared to a gold standard implant (NobelParallel™: NB™, Nobel Biocare™). After surface characterization, the biological behavior assessment was conducted regarding human gingival fibroblasts (hGF) and osteoblast-like cells (MG63). Roughness values for NBTM were Ra = 1.28 µm and for MC® they were Ra = 2.02 µm. Alamar BlueTM assay LIVE/DEADTM staining results indicated equivalent biological development regarding both cell types for the two implants. Significant enhancement was found for hGF ALP activity in the presence of the two tested implants in a time-dependent manner from day 7 to day 14 (** p < 0.01). Alizarin red staining demonstrated significant calcium deposition enhancement when cells were interfaced with the NB™ compared to the MC® implant (** p < 0.05). Moreover, SEM and confocal imaging revealed good cell adhesion with a denser cellular layer on the MC® than the NB™ surface. The MC® cytocompatibility was ranked as equivalent to the gold standard implant despite the surface properties differences. These findings provide new insights about the minimally invasive implant’s biological behavior and its potential clinical implication in different implantology situations.

Evaluate the need for re-intervention on dental coronal restorations in adults seen in a network of general dental practitioners (ReCOL). This observational, cross-sectional, multicenter study involved 40 practitioners and 400 patients. Coronal restoration failures (needing re-intervention for unsatisfactory outcomes) were assessed with a simplified rating scale of seven criteria from the FDI World Dental Federation. The oral health status, the risk factors, and Oral Health Impact Profile-14 were also examined. Previous restoration characteristics (extent, technique, material) were analyzed according to the need for re-intervention (yes/no), the age group, and the risk profile. Qualitative variables were compared between “re-intervention” and “no re-intervention” group using Fisher exact test. The need for re-intervention was estimated at 74% (95% CI: 70; 79); it increased with age (49 to 90%), unfavorable risk profile (82 vs. 62%), and extent of the filling (32, 39, 44, and 44% on 1, 2, 3 surfaces, and crowns, respectively). More posterior than anterior teeth were restored (median per patient: 6 vs. 1) or needed re-intervention (median per patient: 1 vs. 0). The needs for re-intervention in adults are still high within a context of ever-changing materials and techniques, simplified and rationalized decision-makings, and demands for patient involvement. Meeting these needs requires the following: (i) consensus definitions and assessment methods for “failure” and (ii) reliable feedbacks on materials, procedures, and satisfaction. Building large and detailed databases fed by networks of motivated practitioners will help analyzing complex success/failure data by artificial intelligence and guiding treatment and research.

While dental composite long-term aging has already been studied in the past, no data exist about the early aging while it might be detrimental regarding the composites' longevity. This study aims to better understand the effects of early water exposure on dental composites. Dental resin composites with different fillers ratio were subjected to water exposure during 24 h, 1 week, or 1 month. After photopolymerization, the samples were stored at different conditions, whether in wet or dry condition (W, D, respectively) and in wet conditions after a first 24 h storage in dry conditions (DW). Three-point bending tests were performed to measure the flexural modulus. The samples were then subjected to a sorption/desorption protocol. While the matrix alone did not undergo any mechanical degradation with exposure time, the composites matrices presented a decrease in elastic modulus. This decrease was the highest for the matrix with nonsilanized fillers. Interestingly, the DW condition was detrimental for all the samples. Regarding the sample with nonsilanized fillers in DW for 1 month presented an elastic modulus lower than the matrix alone. These results were assigned to the sorption capacity of the polymer matrix, suggesting that the diffusion mechanisms and the nature of water molecules are determinant in the composite degradation. This study showed that dental composite early degradation mechanisms after water exposure are involved in the polymer matrix postpolymerization process as soon as after 24 h. Such mechanisms are detrimental in terms of the dental composite efficiency and have to be understood.

The aim of this scoping review was to present the existing literature regarding the relationship between periodontal diseases and coronavirus disease 2019 (COVID-19). The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) extension for scoping review guidelines was followed. Articles were retrieved from PubMed/MEDLINE and Scopus databases and screened to include studies relating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or COVID-19 to periodontal cells and/or tissues and/or diseases. Twenty-five papers were included; consisting of six reviews, seven original articles, six short reports, four letters to the editor, one commentary, and one case report. The articles were allocated to three different topics: (i) hypotheses on the relationship between periodontal diseases and COVID-19; (ii) risk factors and comorbidities common to periodontitis and COVID-19; (iii) periodontal manifestations of COVID-19. Certain molecules (angiotensin-converting enzyme-2, furin, cathepsin, TMPRSS2...) that are found at a high level in periodontal tissues, particularly in patients with periodontitis, are involved in the mechanism of entry of SARS-CoV-2 into cells. Periodontopathic bacteria could also play a direct role in the mechanism of entry of SARS-CoV-2 by cleaving the S-protein, and the cytokines produced during periodontitis could add to the cytokine storm found in the severe forms of COVID-19. It thus appears that the treatment of periodontitis, which allows a reduction in periodontopathic bacteria and of the local and systemic inflammation state, could be part of a strategy to prevent the development of severe forms of COVID-19.

International audience; Objective. Healing of soft tissues and improvement of aesthetics have become major research objectives in implantology and renewed the interest for ceramics implants. The aim of this study was to evaluate the pre-clinical performance of screw-shaped sandblasted-etched implants processed from an innovative zirconia-based ceramic composite, in comparison to titanium. Methods. Twenty-four ceramic and twenty-four titanium screw-shaped sandblasted-etched dental implants were tested in a splitmouth design in six Beagle dogs. Surface topographies were investigated by confocal microscopy. Local tissue effects were evaluated at 4 and 13 weeks after implantation through histology. An ANOVA statistical analysis (5% risk; p

Different kinds of interactions between the restorative material and mineralized dental tissues result in secondary caries around dental composites. Of these, the mechanical interactions have to be carefully investigated. Due to the elastic mismatch between dental tissues and the composite restoration, complex stresses and strains develop at their interface. This complex mechanical environment disturbs the demineralization-remineralization equilibrium of dental hard tissues. The fluid flow both over and within enamel and dentin, associated with their complex ultrastructure and mechanical behavior, is a key factor. It is known that external mechanical loading can indirectly promote the dissolution of enamel and dentin through a pumping action of cariogenic fluids in and out of microgaps at the interface between mineralized tissues and composite. Mechanical loading can also directly influence the physicochemical behavior of dental hard tissues by inducing complex strain and stress fields on the crystal scale. It is important to consider both the direct and indirect paths by which mechanical loading can influence the apatite dissolution kinetics. Therefore, a system atic approach should be used to investigate the mechanism of secondary caries formation considering the tooth-composite interface as a unique complex in which each element has an influence on the other.

International audience; Background: The protocol study will focus on the seroprevalence of IgG antibodies to SARS-CoV-2 achieved by vaccination and/or natural protection as well as the history, symptoms, and risk factors for SARS-CoV-2 in four primary health-care workers (PHCWs) and their household contacts in metropolitan France. Methods: Here, we propose a protocol for a nationwide survey to determine the seroprevalence of IgG antibodies to SARS-CoV-2 achieved by vaccination and/or natural protection in four PHCW populations (general practitioners, pediatricians, pharmacists and assistants, and dentists and assistants) and their household contacts. Participants will be included from June to July 2021 (Phase 1) among PHCW populations located throughout metropolitan France. They will be asked to provide a range of demographic and behavioral information since the first SARS-CoV-2 wave and a self-sampled dried blood spot. Phase 1 will involve also a questionnaire and serological study of PHCWs’ household contacts. Seroprevalence will be estimated using two ELISAs designed to detect specific IgG antibodies to SARS-CoV-2 in humoral fluid, and these results will be confirmed using a virus neutralization test. This study will be repeated from November to December 2021 (Phase 2) to evaluate the evolution of immune status achieved by vaccination and/or natural protection of PHCWs and to describe the history of exposure to SARS-CoV-2.

International audience; Background: The toxicological risk of Co-Cr dental alloys is actually a sensitive subject with the European regulatory changes, namely regulation (EU) 2017/745 and annex VI to the CLP regulation (EC) 1972/2008.Objectives: The objective of this review is to conduct a rigorous analysis of the cytocompatibility of cobalt–chromium (Co-Cr) dental alloys. Considering various parameters such as cytotoxicity, type IV hypersensitivity reaction, sensitization, and irritation, we investigated evidence of toxicity of Co-Cr in human dental applications.Data sources: Specific search strategies were performed in three electronic databases, namely Medline, Embase, and Web of Science, using a main restriction in the search regarding the publication date (1995–2022).Study selection: Out of a total of 836 articles, only 21 studies were selected and analyzed according to PRISMA methodology.Results: Among them, 10 in vitro studies using human samples and 11 in vivo studies on human patients were distinguished. Most of the in vitro studies confirmed that Co-Cr alloys have a good cytocompatibility compared to Ni alloys. Regarding the in vivo studies, it appeared that Co-Cr could rarely cause sensitization, irritation, and allergic reactions. Reactions were mainly observed for people allergic to Co or Cr. Nevertheless, titanium-based materials showed better results.Conclusions: This study proposes a new state of the art on Co-Cr dental alloys and will thus be very useful for carrying out additional studies.Relevance: This review will help practitioners in their daily clinical choice

Assess the quality of dental restorations with simplified FDI criteria and examine its relationships with other general characteristics of restored teeth.The study involved 76 dentists from private and hospital practices. Assessments of successes and failures of previous restorations used a simplified rating with FDI criteria 3 to 8, 11, 12, and 14. The results were examined versus tooth location, number of restored surfaces, type of restoration, and filling material.The dentists examined 4,612 dental restorations, of which 4,185 direct fillings mainly with resin composite materials (2,555). Of all restorations, 2,048 (44.4%) were considered as failures, of which 1,489 had one or two criteria for 'clinically unsatisfactory/poor restoration'. As simplified, the esthetic criterion 'color match' was the most frequent criterion for failure (912 cases). The rate of restoration failures was found associated with the number of surfaces restored and the use of glass-ionomer cement. Results are not comparable with others obtained with original FDI criteria.Assessing dental restorations with the original FDI criteria leads generally to much more failure statements than practitioners' decisions to reintervene. Though requiring some adjustment (e.g., regarding 'color match'), the simplified assessment proved convenient and amenable to standardization.Regardless of the type of practice, selecting, understanding, and optimal interpreting of FDI criteria for failure is essential to help practitioners faced with daily dilemmas of replacement vs. repair of failed dental restorations. Standardization of simplified criteria is desirable to help comparing research data.

Aim This systematic review aimed to critically summarise the results of clinical studies investigating agents able to: stop the progression of carious lesions; stop the development of new root carious lesions; preserve the vitality of the infected dental tissues; and increase the surface hardness or change of surface texture, in middle-age and older adults.Methods PubMed, Scopus, and Web of Science were searched systematically, following PRISMA guidelines. Clinical trials published from 2011 to 2020 (March) were included. This systematic review is registered in the PROSPERO database (CRD42018104399). Languages were restricted to English.Results Thirteen of 312 studies were eligible for this review. Eight agents were identified in the studies and their efficacy was assessed using different methods. The agents that presented valuable results on preventing or arresting root caries were 38% silver diamine fluoride (SDF), arginine-containing toothpaste and high-fluoride toothpastes.Conclusions Based on the selected studies' findings, annual applications of 38% SDF could be the most effective treatment for root caries in older adults. In addition, the daily use of a 1.5% arginine toothpaste or a high-fluoride toothpaste could also be recommended. More research on root caries-specific diagnostic methods, especially at very early stages, is necessary.

Objective This study investigated whether a sample of anterior resin composite restorations could be differently evaluated in different centers of evaluation by clinical and lay evaluators. Methods Anterior resin composite restorations on high-quality intraoral digital photography were evaluated using FDI criteria (1-5 score) by pairs of clinical and lay evaluators in Brazil (BR), France (FR), Peru (PE), and the United States of America (USA). Scores were allocated as maintenance (1, 2, 3), repair (4) and replacement (5) when comparing clinical evaluators and, as acceptable (1, 2, 3) and unacceptable (4, 5) when comparing clinical vs. lay evaluators and lay vs. lay evaluators. The Chi-square test compared the frequencies of scores among the centers. Results The frequencies of maintaining, repairing, or replacing anterior resin composite restorations given by clinical evaluators varied depending on the evaluation center. BR and PE showed the highest frequencies for repair and replacement, while FR and USA showed the highest frequencies for maintenance. The comparison of frequencies of anterior resin composite restorations accepted or unaccepted by the clinical vs lay evaluators in the same centers showed a significantly higher frequency of acceptable dental restorations coming from clinical evaluators. Comparison between lay evaluators from different centers showed significant higher frequency of unacceptable dental restorations by BR, compared to other centers. Conclusions In the evaluation of anterior resin composite restorations, the maintenance, repair, or replacement trends can vary among different centers. The unacceptable rate came more frequently from lay than from clinical evaluators. Lay evaluators from different centers differed significantly. Clinical Significance Clinical and lay evaluators in distant evaluation centers can present different trends when assessing anterior resin composite restoration. Multicenter evaluations can help to understand such differences and it is important because clinical decision-making based on scientific evidence comes from clinical studies done in different research centers.

Purpose To investigate the relationship between the microstructure of CAD/CAM blocks and the quality of adhesion as function of the surface treatment and resin cement type. Materials and methods Two nano-ceramic composite resin CAD/CAM blocks, Lava Ultimate (LU) and Cerasmart (CS), and two Leucite-reinforced glass ceramic CAD/CAM IPS blocks, Empress® CAD (EM) and InitialTM LRF (IR), received either Hydrofluoric acid (HF) or sandblasting (SB) surface treatments. The blocks were then luted using two dual-cure resin cements, LinkForce (LF) and Multilink Automix (ML) with their corresponding silanes, resulting in 16 study groups. The luted blocks were then thermal-cycling (TC) for 5000 cycles and subjected to a microtensile bond strength (μTBS) test. Scanning electron microscopy (SEM) micrographs of the treated surfaces were analyzed using ImageJ software and XRD analyses were performed for the two ceramic blocks. The data obtained were submitted to Games-Howell post-hoc nonparametric test to compare combinations of groups or treatments and a linear mixed-effects model for the factors surface treatment, block type, and resin cement, together with their first-degree interactions (α = 0.05). Results The lowest mean μTBS values were obtained with LU-HF, whereas the highest mean μTBS values were obtained with CS regardless of resin cement type and surface treatment method. IR-HF mean μTBS were significantly higher than IR-SB, EM-SB, and EM-HF. Analysis using ImageJ software demonstrated significant differences in the density and pore size after HF surface treatment. Conclusions The specific microstructure of each block material within the same family group impacted the micromechanical retention and the bonded interface strength.

International audience; Le 22 septembre 2017, à la surprise d’un grand nombre de professionnels de santé et d’industriels du domaine de la dentisterie, le comité d’évaluation des risques (CER) de l’Agence européenne des produits chimiques (ECHA) a adopté un avis pour réviser la classification et l’étiquetage du cobalt (Co) métallique [1]. Depuis 2020, le Co métallique est ainsi devenu une substance classée cancérigène, mutagène et toxique pour la reproduction (CMR). Ceci n’est pas sans conséquence dans notre pratique quotidienne, notamment en raison de la mise en place progressive (2017-2025) du nouveau règlement (UE) 2017/745 sur les dispositifs médicaux (RDM) [2]. Ce RDM impose de nouvelles exigences envers les dispositifs médicaux contenant une substance classée CMR. Le dispositif médical ne peut alors être mis sur le marché que si aucune alternative n’est disponible et que si une justification est fournie par le fabricant ou par l’organisme notifié (ON) par le fabricant. Par ailleurs, lorsqu’une substance classée CMR fait partie d’un dispositif médical, cela doit être notifié sur l’emballage et le patient/consommateur devra en être aussi informé. Avec la mise en application, le 26 mai 2021, du MDR (UE) 2017/745, la situation des chirurgiens-dentistes va devenir assez inconfortable. L’utilisation fréquente d’alliages dentaires cobalt-chrome (Co-Cr) contenant donc une substance CMR entraînera automatiquement une remise en cause de la pratique professionnelle. Comment en sommes-nous arrivés là? Quel est l’échéancier auquel nous allons devoir faire face à partir de 2021?

Aim To assess the effect of periodontal treatment (PT) on glomerular filtration rate (GFR), systemic inflammation, or mortality in patients with chronic kidney disease (CKD). Methods A literature search was performed on PubMed and Web of Science databases on articles published until December 2019. The PRISMA guidelines were used throughout the manuscript. Results Of the total studies found, only 18 met the inclusion criteria; four retrospective and 14 prospective studies (including 3 randomized controlled trials–RCT). After PT, 3 studies investigated GFR, 2 found significant improvement; 11 (including 2 RCTs) investigated C-reactive protein levels, 9 found a significant improvement (including the 2 RCTs); 5 (including 3 RCTs) investigated Interleukine-6 level, 4 found a significant improvement (including 2 RCTs) and 2 studies evaluated mortality, one (retrospective study) found a significant difference. Conclusions Within the limitations of the present study, PT seems to improve CKD status, especially by reducing the systemic inflammation. Further RCTs are needed to confirm the results and specifically assess the influence of different types of PT in CKD patients. Taking into consideration the ability of PT to prevent further tooth loss and denutrition, early management of periodontitis is extremely important in patients with impaired renal function.

Objectives This study aimed to evaluate the interface between a calcium silicate cement (CSC), Biodentine and dental adhesives in terms of sealing ability. Materials and methods Microleakage test: 160 standardized class II cavities were prepared on 80 extracted human molars. The cavities were filled with Biodentine and then divided into 2 experimental groups according to the time of restoration: composite resin obturation 15 minutes after Biodentine handling (D0); restoration after 7 days (D7). Each group was then divided into 8 subgroups (n = 5) according to the adhesive system used: etch-and-rinse adhesive (Prime & Bond); self-etch adhesive 2 steps (Optibond XTR and Clearfil SE Bond); self-etch adhesive 1 step (Xeno III, G-aenial Bond, and Clearfil Tri-S Bond); and universal used as etch-and-rinse or self-etch (ScotchBond Universal ER or SE). After thermocycling, the teeth were immersed in a silver nitrate solution, stained, longitudinally sectioned, and the Biodentine/adhesive percolation was quantified. Scanning electron microscopic observations: Biodentine/adhesive interfaces were observed. Results A tendency towards less microleakage was observed when Biodentine was etched (2.47%) and when restorations were done without delay (D0: 4.31%, D7: 6.78%), but this was not significant. The adhesives containing 10-methacryloyloxydecyl dihydrogen phosphate monomer showed the most stable results at both times studied. All Biodentine/adhesive interfaces were homogeneous and regular. Conclusions The good sealing of the CSC/adhesive interface is not a function of the system adhesive family used or the cement maturation before restoration. Biodentine can be used as a dentine substitute.

During interventions for deep caries lesions without severe symptoms, preserving pulpal vitality is important to ensure treatment success, improve organ prognosis, and decrease cost-effectiveness. Current pre-operative radiographs allow visual estimation but not accurate measurement of lesion depth. Investigate the ability of ratio ‘remaining/total dentin thickness’ (RDT/TDT, as determined on pre-operative radiographs) to predict pulp exposure during excavation. This retrospective study (January 2018–June 2020) analyzed data on 360 patients. Four independent raters examined standard pre-operative radiographs and their contrasted versions. Lines put at the dentino-enamel junction, the floor of the carious lesion, and the pulp chamber wall allowed deriving RDT/TDT. Inter-rater agreements and concordance were assessed. A logistic regression accounting for measurement errors provided odds ratios that estimated the ability of the RDT/TDT to predict pulp exposure. The median RDT/TDT ratio ranges were 16.8–26.5% on standard and 16.2–24.6% on contrasted radiographs. Inter-rater agreements on RDT/TDT were rather poor and inter-rater reliability was low and similar in standard and contrasted radiographs: the concordance correlation coefficients (95% CIs) were estimated at 0.46 (0.40; 0.51) and 0.46 (0.40; 0.52), respectively. The risk of pulp exposure increased by 2.5 times [odds ratio (95% CI) 2.57 (2.06; 3.20)] per 10-point decrease of the ratio on standard radiographs vs. 4.15 (3.15; 5.46) on contrasted radiographs. RDT/TDT ratio is potentially helpful in predicting pulp exposure. However, the measurement errors on RDT and TDT being non-negligible and the interrater agreements poor, there is still place for advances through development of an automated process that will improve reliability and reproducibility of pulp exposure risk assessment. Trial registration number. ClinicalTrials.gov NCT04607395, October 29, 2020

International audience; This study evaluated the influence of different implant types on (1) radiographic marginal bone levels after healing and (2) radiographic and histomorphometric tissue levels and characteristics following ligature-induced peri-implantitis. Four implant types (Standard Plus, Straumann [S]; NobelReplace Tapered, Nobel Biocare [N]; In-Kone Universal, Global D [I]; and twinKon, Global D [T]) were randomly placed in the edentulous healed mandibular ridge of six dogs (T0), for a total of 57 implants placed. After 10 weeks, a peri-implantitis was ligature-induced (T1). After 12 weeks, biopsy samples were processed for histomorphometric analysis (T2). Standardized radiographs were taken at T0, T1, and T2 for imaging analysis. Statistical analysis was performed using mixed-effects linear modeling. After healing (T1), the radiographic marginal bone level was more coronal for implants I, T, and S compared to N. Following peri-implantitis (T2), the histologic marginal bone level was more coronal for implants I, T, and S compared to N, and for implants I and T compared to S. Also at T2, the radiographic marginal bone level was more coronal at implants I, T, and S compared to N. Implant type may influence bone remodeling during healing and bone loss during the early stages of experimental peri-implantitis.

Evaluate the need for re-intervention on dental coronal restorations in adults seen in a network of general dental practitioners (ReCOL). MATERIALS AND METHODS: This observational, cross-sectional, multicenter study involved 40 practitioners and 400 patients. Coronal restoration failures (needing re-intervention for unsatisfactory outcomes) were assessed with a simplified rating scale of seven criteria from the FDI World Dental Federation. The oral health status, the risk factors, and Oral Health Impact Profile-14 were also examined. Previous restoration characteristics (extent, technique, material) were analyzed according to the need for re-intervention (yes/no), the age group, and the risk profile. Qualitative variables were compared between "re-intervention" and "no re-intervention" group using Fisher exact test.The need for re-intervention was estimated at 74% (95% CI: 70; 79); it increased with age (49 to 90%), unfavorable risk profile (82 vs. 62%), and extent of the filling (32, 39, 44, and 44% on 1, 2, 3 surfaces, and crowns, respectively). More posterior than anterior teeth were restored (median per patient: 6 vs. 1) or needed re-intervention (median per patient: 1 vs. 0).The needs for re-intervention in adults are still high within a context of ever-changing materials and techniques, simplified and rationalized decision-makings, and demands for patient involvement.Meeting these needs requires the following: (i) consensus definitions and assessment methods for "failure" and (ii) reliable feedbacks on materials, procedures, and satisfaction. Building large and detailed databases fed by networks of motivated practitioners will help analyzing complex success/failure data by artificial intelligence and guiding treatment and research.

Thanks to their high porosity and surface area, mesoporous bioactive glasses (MBGs) have gained significant interest in the field of medical applications, in particular, with regards to enhanced bioactive properties which facilitate bone regeneration. The aim of this article is to review the state of the art regarding the biocompatibility evaluation of MBGs and provide a discussion of the various approaches taken. The research was performed using PubMed database and covered articles published in the last five years. From a total of 91 articles, 63 were selected after analyzing them according to our inclusion and exclusion criteria. In vitro methodologies and techniques used for biocompatibility assessment were investigated. Among the biocompatibility assessment techniques, scanning electron microscopy (SEM) has been widely used to study cell morphology and adhesion. Viability and proliferation were assessed using different assays including cell counting and/or cell metabolic activity measurement. Finally, cell differentiation tests relied on the alkaline phosphatase assay; however, these were often complemented by specific bimolecular tests according to the exact application of the mesoporous bioactive glass. The standardization and validation of all tests performed for MBG cytocompatibility is a key aspect and crucial point and should be considered in order to avoid inconsistencies, bias between studies, and unnecessary consumption of time. Therefore, introducing standard tests would serve an important role in the future assessment and development of MBG materials.

Objectives To assess in vitro the effect of experimental mesoporous BAG, on human dental pulp cells (hDPCs) behavior in terms of cytocompatiblity and bioactivity via mineralization potential. Methods Fine (FP) and large particles (LP) of a fixed BAG composition named 0NaMBG have been elaborated by a sol-gel process. In vitro assessment was achieved on cultured primary hDPCs using indirect contact. The effect of the concentration of 800 μg/mL on cell metabolic activity and cytotoxicity were examined by performing Alamar blue and crystal violet assays. Alizarin Red staining was used to detect and quantify the formation of mineralized nodules and ALP activity was colourimetrically quantified. The expression of Odontogenic markers: DMP-1 and osteopontin (OPN) expression and cell morphology was evaluated by confocal microscopy. Results According to the Alamar blue and crystal violet assay, 0NaMBG samples were non-cytotoxic. Cells treated with 0NaMBG particles expressed higher metabolic activity than control cells, especially for LP. Both FP and LP significantly increased both extra and intra cellular ALP activity. hDPCs exhibited good cell spreading and adhesion in the presence of FP and LP extracts by confocal imaging. Further, Alizarin red S assay demonstrated more mineralization nodules and significant enhancement of the extracellular calcium deposition when cells were interfaced with both FP and LP compared to the control cells. Moreover, LP extracts enhanced the production and secretion of odontogenic markers: dentin matrix protein 1 (DMP-1) and osteopontin. Significance LP have a higher surface area and pore volume, which could explain their greater bioactivity in contact with pulp cells. The clinical relevance of these findings implicate that 0NaMBG could be used as fillers in dental therapeutic materials suitable for dentin and/or pulp tissues preservation.

Objectives For more than twenty years, dental practice-based research networks (D-PBRN) have helped to structure clinical research in private practice. They bring together practitioners working in several structures and may include a greater number of subjects. The aims of this study were thus to systematically explore the scientific production from dental private practices in general and to map and describe the D-PBRN activity worldwide. Data sources Two research procedures were carried out in parallel. The first was conducted as a scoping review to examine peer-reviewed literature indexed in the PubMed database and the second was performed on the World Wide Web to identify the main characteristics of the networks (location, scientific production…). Study selection 368 publications were identified among which 202 were published by PBRN members and the others by private practitioners not affiliated to any network. 210 (57 % of the included articles) were produced in the USA. A higher number of diverse centers are involved in each study when it is conducted by a PBRN (59.06 ± 66.59 vs. 13.51 ± 31.58 for networks and independent teams, respectively; p Conclusions Although dental practice-based research has grown over the years, the number of D-PBRN worldwide remains low. Even if it requires some investment to produce research in dental offices, this type of networks helps to fill the gap between private practice and research and to improve knowledge on oral health. Relevance The mapping of all the dental PBRN together with the research topics studied throughout the world make the relevance of this article. The ways to improve practice-based research in dentistry are also discussed in the paper.

International audience; A series of novel borosilicate ionomer glasses composed of varying amount of SiO2–B2O3–K2OeCaO–Al2O3 wereinvestigated. The influence of the thermal treatment was evaluated in terms of ion release and glass microstructure.Inductively coupled plasma optical emission spectrometry (ICP-OES) and scanning electron microscopy(SEM) were the main analytical techniques used in this study. The results show that all the glasses sampleswere amorphous according to the XRD and the SEM results before and after the heat-treatment. However, whilstthe as-quenched samples appeared consistently transparent and colourless, the thermal treatment at 700 °C for20 h induced some of the samples to turn opalescent. The ion concentration profiles suggest that the dissolutionrate of Ca and B were enhanced by the heat treatment in all cases. Moreover, it was confirmed that differentleaching rates exist between the opal and clear samples

International audience; The periodontal biomechanical environment is very difficult to investigate. By the complex geometry and composition of the periodontal ligament, its mechanical behavior is very dependent on the type of loading (compressive vs. tensile loading; static vs. cyclic loading; uniaxial vs. multiaxial) and the location around the root (cervical, middle, or apical). These different aspects of the periodontal ligament make it difficult to develop a functional biomaterial to treat periodontal attachment due to periodontal diseases. This review aims to describe the structural and biomechanical properties of the periodontal ligament. Particular importance is placed in the close interrelationship that exists between structure and biomechanics: the periodontal ligament structural organization is specific to its biomechanical environment, and its biomechanical properties are specific to its structural arrangement. This balance between structure and biomechanics can be explained by a mechanosensitive periodontal cellular activity. These specifications have to be considered in the further tissue engineering strategies for the development of an efficient biomaterial for periodontal tissues regeneration.

International audience; Objective :To assess the impact of the quaternary ammonium antibacterial agent, Dimethyl-Hexadecyl-Methacryloxyethyl-Ammonium Iodide (DHMAI), on structural stability of an experimental resin composite after biological aging.Methods :Experimental resin composites containing 7.5% of DHMAI were incubated in a biological medium in the presence of a Streptococcus Mutans (SM) strain during 3 months. The physicochemical, mechanical, and thermal properties, before and after 3 months of aging, were evaluated using: Degree of Conversion (DC), Residual Functions (RF), Vitreous Transition (Tg), Thermal Expansion Coefficient (CTE) and thermal degradation using Fourier Transform Infrared Spectroscopy Analysis (FTIRATR), Differential Scanning Calorimetry (DSC), Thermo Mechanical analyses (TMA) and Thermo Gravimetric Analysis (TG).Results :Incorporation of DHAMI increased DC and decreased RF. After aging, DHMAI decreased and slowed RF release. Incorporation of 7.5% DHAMI provided significant modification of the thermal behavior (Tg and thermal degradation) but did not affect CTE. After aging, DHMAI enhanced the structural stability and improved resistance against biodegradation compared to the control composite.Significance :The development of an antibacterial dental composite based on DHMAI improved its physical, mechanical, and thermal behaviors, possibly enhancing dental composite longevity. Results suggest that DHMAI could be used in the composition of other bioactive dental materials.

Objective The superior textural properties of sol–gel derived bioactive glasses compared to conventional melt quench glasses accounts for their accelerated bioactivity in vitro. Several studies have explored ways to improve the surface properties of sol–gel glasses in order to maximise their efficiency for bone and tooth regeneration. In this study, we investigated the effect of order of network modifying precursor addition on the textural properties of sol–gel derived bioactive glasses. Methods The effect of precursor addition order on the glass characteristics was assessed by switching the order of network modifying precursor (calcium acetate monohydrate and sodium acetate anhydrous) addition for a fixed composition of bioactive glass (75SiO2:5CaO:10Na2O:10P2O5). Results The results of this study showed that the order of precursor addition does influence the porosity of these glasses. For the glasses of a fixed composition and preparation conditions we achieved a doubling of surface area, a 1.5 times increase in pore volume and a 1.2 times decrease in pore size just by the mixing the network modifying precursors and adding them together in the sol–gel preparation. Significance This simple and straightforward route adaptation to the preparation of bioactive glasses would allow us to enhance the textural properties of existing and novel composition of bioactive glasses and thus accelerate their bioactivity.

MARIO is the main outgrowth of the Mascoti-bio project, which has begun in 2014 thanks to ANSM support. The aim of this project is to propose a new analog simulator of oral cavity, alternative to a...

Objectives In-vitro experiments on ormocers (ORganically MOdified CERamics) have provided controversial results. Consequently, the objectives of this meta-analysis were to (1) compare clinical performances of first generation ormocers versus conventional composite restorations, (2) explore the influence of various clinical factors and the impact of the quality of studies on published results. Methods The following databases were explored until 2017/01/08: Ovid MEDLINE In-Process, Pubmed, CENTRAL, HTA, DARE, LILACS and Google Scholar. Studies of more than two years with quantitative comparisons between ormocers and control groups were selected. Outcome was the failure of a restoration (need to repair, remove or replace). Multivariate random-effects Poisson’s regression was used to obtain a summary estimate. Results 75% of the 8 included trials concerned Class I/II restorations. Although non-significant, the global failures were higher for ormocers (0.22 [−0.16; 0.61]). For Class I/II restorations, a significantly higher sensitivity was observed for ormocer-based materials compared to other composites (0.75 [0.01; 1.50]). An increase of the number of restorations per patient was associated with higher marginal adaptation failures for ormocers in Class I/II obturations (0.59 [0.11; 1.08]). Significance This study did not identify clear advantages of using the first generation of ormocer-based fillings rather than conventional composites. Given the recent development of new, dimethacrylate-diluent-free ormocer matrices, potentially more stable and resistant, new randomized clinical trials should be developed comparing this new family of pure ormocers with current composites.

Objective Many new dental composites containing mesoporous silica fillers have been developed to improve rheological properties and enhance the resin–filler interface. To investigate the correlation between the cytocompatibility of several dental composites and their composition; two aspects have been considered: presence of bisphenol A (BPA)-glycidyl methacrylate (Bis-GMA) or triethyleneglycol-dimethacrylate (TEGDMA) among the resin monomers and presence of porous particles among the filler blends. Methods Five commercial composites with different resin matrices and mineral fillers were compared to four experimental composites designed without any BPA-based monomers or TEGDMA. Porous fillers, with or without silanation, were added in some of the experimental composites. Two reference resin matrices were also selected. Cytocompatibility with cultured primary human gingival fibroblasts was assessed by confocal laser scanning microscopy with time-lapse imaging. Fourier transform infrared spectroscopy was used to control monomer conversion rate. Results Conversion rates of the experimental composites ranged from 57% to 71%, a comparable ratio for dental composites. Experimental samples were better tolerated than tested commercial samples not containing TEGDMA and significantly better than those containing TEGDMA. Experimental composites with porous fillers exhibited good cytocompatibility, especially when surfaces were silanated. Significance Cytotoxicity was associated with resin amount and especially resin nature. Composites containing porous fillers might behave as if the resin trapped into pores has no effect on toxicity. The cytotoxicity of composites with and without BPA derivatives was mainly attributed to the release of residual TEGDMA rather than the BPA derivatives.