How French dentists manage defective restorations: Evidence from ReCOL the French dental practice-based research network--A survey study.

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.

Knowledge and Opinions of French Dental Students in Operative Dentistry - Management of Deep Carious Lesions.

PURPOSE: A questionnaire survey was recently undertaken among French dental students (FDSs) to investigate their practices, knowledge and opinions in various domains of minimal intervention (MI) in cariology. The present work focuses on management of deep carious lesions (DCLs). MATERIALS AND METHODS: The questionnaire was administered (Spring 2018) to all the fifth-year students of the 16 French dental schools. Descriptive analyses were performed. RESULTS: Among 1370 FDSs (response rate: 84.5%), hardness was the most commonly reported criterion for assessing the endpoint of carious tissue removal (53.9%), followed by firm dentin (40.0%). Regarding FDSs' opinion of leaving carious dentine under a restoration, 41.9% of the respondents agreed that carious tissues should always be removed completely. For an asymptomatic tooth with DCLs and exposed pulp, direct pulp capping was mainly chosen (93.9%). In a clinical case correctly diagnosed as a reversible pulpitis by 79.7% of respondents, nearly half of FDSs chose a one-step complete excavation (48.3%) followed by selective excavation (25.1%), then two-step complete excavation (20.9%) and a minority (5.7%) opted for pulpal therapy (biopulpotomy or endodontic treatment). CONCLUSION: The present results suggest an inadequate dissemination of MI concepts among FDSs towards DCL management. The present results show the need for a harmonisation and a reinforcement of teaching evidence-based MI according to the latest European recommendations.

Knowledge and Opinions of French Dental Students Toward Occlusal and Proximal Restorative Thresholds.

PURPOSE: To investigate the practices, knowledge and opinions of French dental students (FDSs) in various domains of minimal intervention (MI) in cariology. MATERIALS AND METHODS: A cross-sectional, questionnaire-based study was conducted in spring 2018 among all fifth-year French dental students (FDSs) from the 16 French dental schools. The present article focuses on restorative management. Statistical analyses (descriptive, chi-squared) were performed. RESULTS: The response rate was 84.5%. Overall, 97.4% of respondents would have operatively intervened for proximal and 83% for occlusal carious lesions, respectively, while non-or micro-invasive intervention would have been possible. Interestingly, 15% would completely open the occlusal fissures. For both occlusal and proximal lesions requiring a restoration, composite resin was indicated by over 95% of the respondents. In a clinical case, 51.6% of FDSs who rightly diagnosed an enamel carious lesion would operatively intervene. When FDSs could not diagnose the type of carious lesions, a high proportion of invasive actions were also reported (40%). FDSs who read scientific articles were more likely to consider the high importance of not filling sound teeth unnecessarily (p = 0.033). CONCLUSION: FDSs do not have sufficient awareness of MI guidelines regarding occlusal and proximal restorative thresholds. Efforts are required in dental schools to teach FDSs to postpone invasive/restorative strategies to later stages of carious progression. There is a need to strengthen prevention techniques and non-invasive options in the teaching of MI in cariology.

Knowledge and opinions of French dental students related to caries risk assessment and dental sealants (preventive and therapeutic).

OBJECTIVES: A national questionnaire study was performed to document knowledge and opinions of French dental students (FDSs) about minimal intervention (MI) in dentistry especially caries risk assessment (CRA) and dental sealants (DSs). MATERIALS AND METHODS: A questionnaire was administered to the fifth-year dental FDSs (n = 1370) from the 16 French dental schools. Descriptive and statistical analyses were performed. RESULTS: The response rate was 84.5%. A large majority of respondents (87.8%) linked MI with minimally invasive dentistry and 77.4% considered MI as a concept based on prevention. About 80% stated they use CRA in clinical practice, mostly without any specific form. If 80.4% of the respondents would base their treatment plans on CRA, only 55.1% would regularly plan preventive regimens according to individual risk level. However, while 96.6% declared they perform preventive DSs, only 44.3% considered therapeutic sealants as a routine treatment. Although 75.1% of FDSs stated that they had sufficient learning and training related to CRA, 55.9% thought that they need further education about preventive and therapeutic DSs. CONCLUSION: Although FDSs seem to be aware of the importance of CRA and preventive strategies, this study shows the need to harmonize the teaching in cariology according to the latest European recommendations. CLINICAL RELEVANCE: A national questionnaire study showed variability towards knowledge and opinions of FDSs related to MI in cariology. This may impact care provisions in their future professional life showing the urgent need to harmonize the teaching of MI in cariology in France.

Periodontal disorders in a cohort of patients with Cohen syndrome.

AIMS: Cohen syndrome (CS) is an uncommon autosomal recessive disorder due to mutations in vacuolar protein sorting 13B, with an intermittent presence of neutropenia. Contrary to other clinical phenotypic features, oral health has been little investigated in CS. We described oral health and dental hygiene in a cohort of CS patients. METHODS AND RESULTS: Twelve CS patients with neutropenia (<1500/mm3 ) were recruited in the dental department of Dijon University Hospital (France). Patients underwent oral examination, and blood samples were collected. Oral health markers were described and compared between patients with moderate and severe neutropenia (<500/mm3 ). In 12 patients (mean age = 21.1 years, SD = 13.7, six females), 45.5% brushed at least twice daily their teeth, and the same percentage annually visited a dentist. Dental plaque index was high (mean = 1.7, SD = 1.4). So was the number of lost teeth per patient, notably among adults (mean = 13.8, SD = 9.8). Elevated markers of periodontitis were noted as percentage of bleeding dental sites (mean = 70.2%, SD = 45.2%) or Gingival Index (mean = 2.2, SD = 1.0). The severity of neutropenia was correlated to the level of tooth-loss (P = .03). CONCLUSION: This study highlighted in CS patients worrisome oral health and dental follow-up in the context of intellectual disability with behavioural anomalies. More attention is needed by care-givers on oral condition in CS.

Structural stability of DHMAI antibacterial dental composite following in vitro biological aging.

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.

Performance of Fluorescence-based Systems in Early Caries Detection: A Public Health Issue.

AIM: Modern clinical caries management involves early stage caries diagnosis and should fit with dental health policy. The objective of this study was to achieve early caries detection in enamel and dentine with a laser-based system (DIAGNOdent™ pen) first and secondary with a new fluorescence intra-oral camera (Soprolife®). A visual inspection with a loupe was used as control. MATERIALS AND METHODS: Following the consolidated standards of reporting trials recommendations, 628 occlusal fissures were included for analysis. RESULTS: The sensitivity and specificity of both devices varied depending on the cutoff threshold of the caries score, and the ROC curve showed higher values for the Soprolife® than for DIAGNOdent™ pen. The values of the area under the curve decreased from 0.81 (Soprolife® in daylight) to 0.79 (Soprolife® in fluorescent mode) and 0.67 for DIAGNOdent™ pen. DIAGNOdent™ pen reproducibility (intra and inter-investigator) showed a wide dispersion, with many values scattered beyond the confidence limits (±2 SD), and the weighted kappa coefficient, which was quite low (0.58), confirmed this tendency. CONCLUSION: Caries prevalence in terms of public health policy is of interest and caries detection increased significantly when using an fluorescence-based intra-oral camera. CLINICAL SIGNIFICANCE: The clinical significance of these findings is that fluorescence could help improve caries diagnosis, reduce clinical misinterpretations, and finally benefit the patients. How to cite this article: Terrer E, Slimani A, Giraudeau N, et al. Performance of Fluorescence-based Systems in Early Caries Detection: A Public Health Issue. J Contemp Dent Pract 2019;20(10):1126-1132.

Marginal and internal fit of CAD-CAM inlay/onlay restorations: A systematic review of in vitro studies.

STATEMENT OF PROBLEM: Different parameters can influence the adaptation of computer-assisted design and computer-assisted manufacturing (CAD-CAM) inlay/onlay restorations. However, systematic reviews to identify and discuss these parameters are lacking. PURPOSE: The purpose of this systematic review was to summarize the scientific literature investigating all parameters that can influence both the marginal and internal adaptation of CAD-CAM inlay/onlay restorations. MATERIAL AND METHODS: An electronic search was conducted by 2 independent reviewers for studies published in English between January 1, 2007 and September 20, 2017 on the PubMed/MEDLINE, Scopus, and Web of Science databases and in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Factors investigated in the selected articles included the type of CAD-CAM system, virtual space parameters, version of the software, type of block, luting procedure, type of restoration, sample size and aging procedure, evaluation method, and number of measurement points per specimen. RESULTS: A total of 162 articles were identified, of which 23 articles met the inclusion criteria. Nine studies investigated adaptation with different restorative materials, 2 evaluated adaptation according to the type of preparation design, 9 compared adaptation before/after thermomechanical loading, and 2 before/after cementation, 1 study investigated marginal adaptation based on whether the optical scan was made intraorally or extraorally, 1 compared adaptation with 5 and 3 axis CAM systems, and 1 assessed adaptation with 4 different intraoral scanners. The risk of bias was high for 7, medium for 15, and low for 1 of the studies reviewed. The high level of heterogeneity across the studies excluded meta-analysis. CONCLUSIONS: Most of the studies reported clinically acceptable values for marginal adaptation. The performance of a CAD-CAM system is influenced by the type of restorative material. A nonretentive cavity preparation exhibited better adaptation than a retentive preparation. Most studies showed that thermomechanical loading affected the quality of marginal adaptation. Cementation increased marginal discrepancies. No statistically significant difference was found for marginal fit of onlays between intraoral and extraoral optical scans using a stone die. The number of milling axes, the type of digital camera, and the region measured were statistically significant in relation to marginal/internal adaptation. Values of adaptation recorded failed to reproduce the preestablished spacer parameters in the software. Clarification is needed concerning adaptation according to the type of preparation design, the type of material, the choice of intrinsic parameters for the CAD process, the type and shape of milling instruments, and the behavior of the material during milling. Adaptation of CAD-CAM inlay/onlays should be evaluated under clinical conditions.

Mechanical properties and internal fit of 4 CAD-CAM block materials.

STATEMENT OF PROBLEM: Recent polymer-based computer-assisted design and computer-assisted manufacturing (CAD-CAM) materials have been commercialized for inlay restorations, a polymer-infiltrated ceramic-network (PICN) and composite resin nanoceramics. Little independent evidence regarding their mechanical properties exists. Internal adaptation is an important factor for the clinical success and longevity of a restoration, and data concerning this parameter for inlays made with these blocks are scarce. PURPOSE: The purpose of this in vitro study was to evaluate and compare the mechanical properties (flexural strength, flexural modulus, Vickers hardness, fracture toughness) and the internal adaptation of these recent polymer-based blocks with a lithium disilicate glass-ceramic block. MATERIAL AND METHODS: The materials tested in this study were a PICN material (Vita Enamic), 2 composite resin nanoceramics (Lava Ultimate; 3M ESPE and Cerasmart; GCDental Products), and a lithium disilicate glass-ceramic (IPS e.max CAD). Mechanical properties were evaluated according to ISO norm DIS 6872:2013. Bar-shaped specimens (18×3×3 mm) were prepared and submitted to a 3-point bend test using a universal testing machine at a cross-head speed of 0.5 mm/min. In addition, identical cavities were prepared in 60 human mandibular extracted molars (n=15) and optically scanned to receive mesioocclusodistal inlays milled with the 4 materials tested in a CEREC Inlab milling machine. The replica technique and a stereomicroscope (×20) were used to measure the internal fit of the inlays at 9 preselected locations. All data were statistically analyzed using 1-way ANOVA and the post hoc Tukey multiple comparison or Games-Howell test (α=.05). RESULTS: The mean flexural strength of the tested blocks ranged from 148.7 ±9.5 MPa (Vita Enamic) to 216.5 ±28.3 MPa (Cerasmart). The mean flexural modulus ranged from 23.3 ±6.4 GPa (Vita Enamic) to 52.8 ±10.5 GPa (IPS e.max CAD). The mean Vickers hardness ranged from 0.66 ±0.02 GPa (Cerasmart) to 5.98 ±0.69 GPa (IPS e.max CAD). The mean fracture toughness ranged from 1.2 ±0.17 MPa.m1/2 (Cerasmart) to 1.8 ±0.29 MPa.m1/2 (IPS e.max CAD). The values for internal discrepancy ranged from 119 ±55 µm to 234 ±51 µm. The mean internal discrepancy was significantly higher for Lava Ultimate (P<.05) than IPS e.max CAD and Cerasmart but not for Vita Enamic. The factor ''material'' was statistically significant in relation to the mechanical properties evaluated in this study (P<.05). The Pearson correlation was negative between the flexural strength results and the internal discrepancy of the materials tested (R2=0.941; P<.05). CONCLUSIONS: The mechanical properties of the CAD-CAM block materials tested were within the acceptable range for fabrication of single restorations according to the ISO standard for ceramics (ISO 6872:2008). IPS e.max CAD and Cerasmart were observed to have superior flexural strength and better internal fit.

Effectiveness of the DHMAI monomer in the development of an antibacterial dental composite.

OBJECTIVE: Development of antibacterial dental composites is the ultimate goal to decrease carious disease occurrence and increase the restoration longevity. For this purpose, the quaternary ammonium dimethyl-hexadecyl-methacryloxyethyl-ammonium iodide (DHMAI) and the methacryloyloxyethylphosphorylcholine (MPC) have been incorporated in experimental methacrylate-based composite resins. This aims to first investigate the effect of each alone and then their combined effect. METHODS: Synthesized DHMAI and commercial MPC were added either alone or combined at different concentrations to experimental dental composite. Flexural strength (FS) and modulus (FM) were tested to select the optimal concentrations. Only selected composites were evaluated for Vickers hardness (HV) and the degree of conversion (DC) using fourier transform infrared spectroscopy analysis (FTIR-ATR). Antibacterial activity was assessed using tests on colony-forming unit (CFU), scanning electron microscopy (SEM) and Alamarblue assay to measure the metabolic activity. Streptococcus mutans biofilm was chosen to be grown on the composite surfaces during 96h at 37°C. RESULTS: Incorporation of 7.5% DHMAI in composite improved the degree of conversion and gave a strong antibacterial effect with a reduction of (∼98%) in CFU and (∼50%) of metabolic activity with acceptable mechanical properties. Addition of MPC to DHMAI affects mechanical properties of composites without providing a better antibacterial activity. SIGNIFICANCE: Composites with DHMAI greatly reduced S. mutans biofilm and improved the degree of conversion without scarifying the composites' mechanical properties. DHMAI may have wide applicability to other dental materials in order to inhibit caries and improve the longevity of restorations.

Conservative approach of a symptomatic carious immature permanent tooth using a tricalcium silicate cement (Biodentine): a case report.

The restorative management of deep carious lesions and the preservation of pulp vitality of immature teeth present real challenges for dental practitioners. New tricalcium silicate cements are of interest in the treatment of such cases. This case describes the immediate management and the follow-up of an extensive carious lesion on an immature second right mandibular premolar. Following anesthesia and rubber dam isolation, the carious lesion was removed and a partial pulpotomy was performed. After obtaining hemostasis, the exposed pulp was covered with a tricalcium silicate cement (Biodentine, Septodont) and a glass ionomer cement (Fuji IX extra, GC Corp.) restoration was placed over the tricalcium silicate cement. A review appointment was arranged after seven days, where the tooth was asymptomatic with the patient reporting no pain during the intervening period. At both 3 and 6 mon follow up, it was noted that the tooth was vital, with normal responses to thermal tests. Radiographic examination of the tooth indicated dentin-bridge formation in the pulp chamber and the continuous root formation. This case report demonstrates a fast tissue response both at the pulpal and root dentin level. The use of tricalcium silicate cement should be considered as a conservative intervention in the treatment of symptomatic immature teeth.

Tensile and shear bond strength evaluation of a total-etch three-step and two self-etching one-step dentin bonding systems.

PURPOSE: The aim of this study was to compare the bond strengths of two new self-etching one-step (Prompt L-Pop 2 and Adper Prompt L-pop) to a total-etch three-step dentin bonding system (Scotchbond Multipurpose Plus). MATERIALS AND METHODS: One hundred twenty human molars were randomly divided into 3 groups of 40 specimens each. Dentin surfaces of each group were bonded with either Scotchbond Multipurpose Plus (SMP), a three-step system, Prompt L-Pop 2 (PLP), or Adper Prompt L-Pop (APLP), two one-step bonding systems--according to manufacturers' recommendations. After adhesive application, a composite resin cylinder was incrementally built in a Teflon mold (5 mm high and 5 mm in diameter). The samples of each group were randomly divided into 2 subgroups of 20 samples each and were tested in a shear bond or in a tensile bond strength mode (crosshead speed 5 mm/min). Statistical analyses were performed with one-way ANOVA and Student's t-test. RESULTS: The significantly lowest shear and tensile bond strength values were obtained with APLP. PLP revealed higher shear bond strengths than APLP and SMP. There were no differences in tensile bond strengths between PLP and SMP (p < 0.05). CONCLUSION: The results of this in vitro study showed that the chemical modifications (adjunction of monomers and copolymers) of the self-etching all-in-one system APLP did not improve its mechanical properties.

In vitro study of a neodynium:yttrium aluminum perovskite laser on human nonexposed pulp after cavity preparation.

PURPOSE: The aim of this study was to investigate dental pulp reactions after a neodynium:yttrium aluminum perovskite laser pulse on the dentinal floor of occlusal cavities in an in vitro model. METHODS: A Lokki dt laser was used at 30 Hz, 5 W, and 160 mJ for 0.5 s. The pulp reactions were analyzed in a previously described human tooth slice cultured model. The following markers were identified by immunohistochemistry: collagens I, III, and IV and HLA-DR-positive cells. RESULTS: After 4 days of culture, under laser pulse, a concentration of type III collagen beneath the odontoblast layer, a higher level of vessels and an accumulation of HLA-DR-positive cells were routinely observed subjacent to the cavity. CONCLUSION: This laser treatment leads to the first step of rapid pulp repair under culture conditions.