Selected and simplified FDI criteria for assessment of restorations.

OBJECTIVES: Assess the quality of dental restorations with simplified FDI criteria and examine its relationships with other general characteristics of restored teeth. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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. CLINICAL SIGNIFICANCE: 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.

Design of 3D-printed macro-models for undergraduates' preclinical practice of endodontic access cavities.

INTRODUCTION: Endodontic access cavity is one of the steps most feared by dental students. The objective of the present work was to show the design phases of different realistic macro-models of a lower first molar, showing root canal anatomy and the ideal access cavity. MATERIALS AND METHODS: Virtual models were designed with MeshMixer, MeshLab and Blender from the data collected (X-rays, CBCT and optical impression) and then printed. Two types of printers-FDM (fused deposition modelling) and SLA (stereolithography) printers-were used to obtain different prototypes which led to final models. A satisfaction questionnaire was then sent to students, after manipulation, to assess the relevance of these models. RESULTS: Two final models of a lower first molar with an extended size (×9) were finally printed with an SLA laser printer with a transparent liquid resin. The first model represented the tooth with its optimal endodontic access cavity. The second one was designed to be divided into two parts according to a mesio-distal axis in order to visualise the root canal system. Most students found these macro-models to be effective tools for endodontic training. DISCUSSION: 3D printing is a proven technology which is no exception in dentistry. Some authors have already proposed 3D-printed replicas of teeth for endodontic education. Macro-models have been designed, printed and made available to students during preclinical courses before and during training. CONCLUSION: These educational macro-models should strengthen the knowledge and skills of students to improve their clinical and future practice within the dental office.

Dental students' observations about teaching of endodontic access cavities in a French dental school.

INTRODUCTION: Teaching in French universities has undergone deep changes for several years. Dental studies are no exception to the rule. Endodontics is one of the most difficult fields requiring good knowledge of anatomy before performing clinical procedures. The access cavity is the key step of endodontic therapy. The aim of this study was to collect and understand what students feel and expect from theoretical and practical training on endodontic access cavity. MATERIALS AND METHODS: A questionnaire survey on the teaching and learning of endodontic access cavities in a French dental school was sent by e-mail to the 4th-year students (n = 66). The questionnaire consisted of 13 questions of different formats. Qualitative variables were analysed using a word cloud according to the words of the participants. Students were also asked how to improve teaching with new educational tools. RESULTS: 60 students answered the questionnaire (response rate of 90.9%). When students were asked which stage of endodontic treatment they feared the most, performing access cavity came in 3rd place. Upper molar (71%) and lower molar (58%) appeared to have the most difficult endodontic access cavities. Within the word cloud gathered after students' answers analysis, the words "fear," "perforation," "cavity" and "axis" were highlighted. Amongst the 3 new educational tools proposed to students, most were in favour of realistic models of teeth with their ideal endodontic access cavity (79%). DISCUSSION: This study highlighted the feelings of students during their hands-on training on endodontic access cavities. Although they seemed satisfied with practical classes on endodontic access cavities, this step seemed to be stressful for students especially because of the great internal anatomical variabilities of teeth. To help them better understand the root canal anatomy and improve their training, students asked for new educational resources, especially macro-models of teeth with their optimal access cavities. CONCLUSION: This study showed that students are seeking for innovative resources in addition to traditional resources that would make it easier for them to visualise the root canal system and help them feel more comfortable and facilitate learning when performing endodontic access cavities.

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.

Endodontic treatment of a hypertaurodontic mandibular left second molar in a patient with many taurodonts combined with multiple pulp stones.

Taurodontism is a rare embryologic anomaly of teeth, defined by an apical displacement of the furcation of roots and enlarged pulp chambers. Taurodontism has been classified as hypo-, meso- or hypertaurodontism according to the severity of the anomaly. The aim of this case report was to illustrate a clinical case with multiple bilateral taurodonts and to describe the endodontic management of the hypertaurodontic mandibular left second molar with a C-shaped canal and extensive dental pulp calcifications. A healthy 20-year-old male patient was referred for the endodontic treatment of his lower left second molar. Cone beam computed tomography revealed a C-shaped root canal configuration and several dental pulp calcifications in this tooth. The endodontic treatment was performed in two appointments under an operating dental microscope. A panoramic radiograph, made during the 18 months follow-up appointment, revealed nine other taurodontic molars, most of them associated with dental pulp calcifications.

The use of FDI criteria in clinical trials on direct dental restorations: A scoping review.

OBJECTIVES: A scoping review was conducted to explore the use of FDI criteria 10 years after their introduction. The first aim was to compare the amount of studies using the FDI and/or the modified USPHS criteria. The second aim was to analyse the use of the FDI criteria in clinical trials evaluating direct dental restorations. DATA: Listing of studies using FDI and/or USPHS criteria per year since 2007. Clinical studies related to the assessment of direct restorations using FDI criteria. SOURCE: Two systematic searches - regarding the use of FDI and modified USPHS criteria - were carried out on Medline/Pubmed in order to identify the studies published between 2007 and 2017. Authors of the included articles were contacted to clarify their choice of FDI criteria in their studies. ClinicalTrials.gov database was also queried for the on-going studies that use FDI and modified USPHS criteria. STUDY SELECTION: In the first review, all the clinical trials (randomized/non-randomized, controlled, prospective/retrospective studies) that used FDI criteria to evaluate direct restorations on primary or permanent teeth were included. CONCLUSIONS: 16.3% of the studies used FDI criteria. The percentage of studies using them increased from 4.5% in 2010 to 50.0% in 2016. In average, 8.5 FDI criteria were used. The most employed criteria were: marginal adaptation (96.7%), staining (90.0%), fracture of material and retention (90.0%), recurrence of caries/erosion/abfraction (90.0%), post-operative sensitivity/tooth vitality (86.7%) and surface luster (60.0%). In addition, among the 27 on-going studies from ClinicalTrials.gov database, 51.9% use FDI criteria (including 87.5% with an open recruitment status). CLINICAL SIGNIFICANCE: FDI criteria were reported as practical (various and freely selectable), relevant (sensitive as well as appropriate to current restorative materials and clinical studies design), standardized (making comparisons between investigations easier). Investigators should go on using them for a better standardization of their clinical judgment, allowing comparisons with other studies.

Spheroid model study comparing the biocompatibility of Biodentine and MTA.

The primary objective of this study was to assess the biological effects of a new dentine substitute based on Ca3SiO5 (Biodentine™) for use in pulp-capping treatment, on pseudo-odontoblastic (MDPC-23) and pulp (Od-21) cells. The secondary objective was to evaluate the effects of Biodentine and mineral trioxide aggregate (MTA) on gene expression in cultured spheroids. We used the acid phosphatase assay to compare the biocompatibility of Biodentine and MTA. Cell differentiation was investigated by RT-qPCR. We investigated the expression of genes involved in odontogenic differentiation (Runx2), matrix secretion (Col1a1, Spp1) and mineralisation (Alp). ANOVA and PLSD tests were used for data analysis. MDPC-23 cells cultured in the presence of MTA had higher levels of viability than those cultured in the presence of Biodentine and control cells on day 7 (P = 0.0065 and P = 0.0126, respectively). For Od-21 cells, proliferation rates on day 7 were significantly lower in the presence of Biodentine or MTA than for control (P < 0.0001). Col1a1 expression levels were slightly lower in cells cultured in the presence of MTA than in those cultured in the presence of Biodentine and in control cells. Biodentine and MTA may modify the proliferation of pulp cell lines. Their effects may fluctuate over time, depending on the cell line considered. The observed similarity between Biodentine and MTA validates the indication for direct pulp-capping claimed by the manufacturers.