Effectiveness of adhesive containing MDPB: A practice-based clinical trial.

OBJECTIVES: This prospective practice-based trial assessed the longevity of composite restorations made with an adhesive containing an antibacterial monomer compared to a conventional adhesive. METHODS: 9 general practices in the Netherlands were provided with two composite resin adhesives, each for a period of 9 months. Adhesive P contained the quaternary ammonium salt MDPB, and Adhesive S was a control. Patient's age and caries risk, as well as tooth type/number, reason for restoration placement, used restorative material and adhesive, and restored surfaces were recorded. All interventions carried out on these teeth in the 6 years after restoration were extracted from the electronic patient records, along with their date, type, reason, and surfaces. Two dependent variables were defined: general failure, and failure due to secondary caries. All data handling and multiple Cox regression analysis were carried out in R 4.0.5. RESULTS: 11 dentists from 7 practices made 10,151 restorations over a period of two years in 5102 patients. 4591 restorations were made with adhesive P, whereas 5560 were made with adhesive S. The observation period was up to 6.29 years, median observation time was 3.74 years. Cox regression showed no significant difference between the two adhesive materials when corrected for age, tooth type and caries risk, for general failure nor failure due to caries. SIGNIFICANCE: No difference in restoration survival could be shown between composite restorations made using an adhesive containing MDPB and control. Restorations made with the adhesive containing MDPB also did not fail more or less frequently due to secondary caries. This trial is registered on clinicaltrials.gov with identifier NCT05118100.

The salivary proteome in relation to oral mucositis in autologous hematopoietic stem cell transplantation recipients: a labelled and label-free proteomics approach.

BACKGROUND: Oral mucositis is a frequently seen complication in the first weeks after hematopoietic stem cell transplantation recipients which can severely affects patients quality of life. In this study, a labelled and label-free proteomics approach were used to identify differences between the salivary proteomes of autologous hematopoietic stem cell transplantation (ASCT) recipients developing ulcerative oral mucositis (ULC-OM; WHO score ≥ 2) or not (NON-OM). METHODS: In the TMT-labelled analysis we pooled saliva samples from 5 ULC-OM patients at each of 5 timepoints: baseline, 1, 2, 3 weeks and 3 months after ASCT and compared these with pooled samples from 5 NON-OM patients. For the label-free analysis we analyzed saliva samples from 9 ULC-OM and 10 NON-OM patients at 6 different timepoints (including 12 months after ASCT) with Data-Independent Acquisition (DIA). As spectral library, all samples were grouped (ULC-OM vs NON-OM) and analyzed with Data Dependent Analysis (DDA). PCA plots and a volcano plot were generated in RStudio and differently regulated proteins were analyzed using GO analysis with g:Profiler. RESULTS: A different clustering of ULC-OM pools was found at baseline, weeks 2 and 3 after ASCT with TMT-labelled analysis. Using label-free analysis, week 1-3 samples clustered distinctly from the other timepoints. Unique and up-regulated proteins in the NON-OM group (DDA analysis) were involved in immune system-related processes, while those proteins in the ULC-OM group were intracellular proteins indicating cell lysis. CONCLUSIONS: The salivary proteome in ASCT recipients has a tissue protective or tissue-damage signature, that corresponded with the absence or presence of ulcerative oral mucositis, respectively. TRIAL REGISTRATION: The study is registered in the national trial register (NTR5760; automatically added to the International Clinical Trial Registry Platform).

[Measuring tooth wear with regular intra-oral 3D scanners: for still in the future, or is it already possible?] / Serie: Innovatieve technieken en ontwikkelingen in de mondzorg. Meten van gebitsslijtage met reguliere 3D-scanners: toekomstmuziek, of al mogelijk?

Quantitative tooth wear measurement is a method of increasing importance when measuring tooth wear progression. The Radboud university medical center has developed a protocol that measures height and volumetric differences on regular 3D-scans. Intra-oral scans were made on patients with tooth wear and superimposed. To assess reliability the precision , as well as intra- and inter-rater precision of the protocol was tested. T-tests were performed to determine the structural and random error. Our findings indicate that the method is precise enough to measure height differences in patients with severe tooth wear progression, or tooth wear with an interval longer than 1 year. The method is not precise enough to measure volumetric changes.

[Oral chronic graft versus host disease, what is it and how is it treated?] / Orale chronische graft-versus-hostziekte, wat is het en hoe wordt het behandeld?

Allogeneic stem cell transplantation can cause chronic graft versus host disease (cGVHD). A number of patients manifest cGVHD in and around the mouth. It can present itself as clinically as mucosal lesions and/or salivary gland dysfunction and/or sclerotic changes. Cheeks and tongue are most commonly affected, but the palate, gingiva and lips can also be impacted. Oral cGVHD is associated with mucosal sensitivity, pain, (severe) oral dryness, altered taste, restricted mouth opening and difficulty swallowing, all of which may contribute to a significant decrease of the patient's quality of life. Patients also run an increased risk of developing squamous cell carcinoma of the oral mucosa. The diagnosis of cGVHD is almost always based on the patient's medical history and clinical picture. Treatment of symptoms is based on the patient's problem(s). Dental professionals can provide patients with supportive preventive care aimed at reducing symptoms and preventing further deterioration of oral health.

Randomized controlled trial on the performance of direct and indirect composite restorations in patients with severe tooth wear.

OBJECTIVE: The study aimed to evaluate survival and failure behavior of Direct Composite Restorations (DRC) and Indirect Composite Restorations (ICR) on molars and anterior teeth, in a Randomized Controlled Trial (RCT). METHODS: Patients with generalized severe tooth wear were included, and randomly assigned to one of 2 protocols: (1) DCR: All teeth were restored with directly applied micro-hybrid composite restorations (Clearfil AP-X, Kuraray) for load bearing areas and nano-hybrid composite restorations (IPS Empress Direct, Ivoclar Vivadent) for buccal veneers; (2) ICR: First molars were restored with indirect composite 'tabletop' restorations and maxillary anterior teeth were restored with indirect palatal veneer restorations (Clearfil Estenia C&B, cemented with Panavia F, Kuraray). Remaining teeth were restored directly. Restorations were evaluated after 3 years, focusing on clinical acceptability. Statistical analysis was performed using Kaplan Meier curves, Annual Failure Rates (AFRs), and univariate Cox regression analyses (p < 0.05). RESULTS: 41 patients (age: 36.6 ± 6.6y) were evaluated after 3 years (40.0 ± 2.2 m). 408 restorations on first molars and palatal veneers on maxillary anterior teeth were part of this RCT, with 220 DCRs and 188 ICRs. No differences in survival between treatment modality for palatal veneers for any failure criteria were found. Tabletop restorations on first molars showed a considerable higher failure rate for ICR compared to DCR (p = 0.026, HR: 3.37, 95%CI = 1.16-9.81). SIGNIFICANCE: In this RCT, directly applied composite restorations showed superior behavior compared to the indirect composite restorations, when used in the molar region.

[Self-reported oral health and oral health behaviour of asylum seekers]. / Zelfgerapporteerde mondgezondheid en mondgezondheidsgedrag van asielzoekers.

In order to assess the oral health and oral health behaviour of asylum seekers in the Netherlands, 542 asylum seekers completed questionnaires. There were questionnaires for the groups children (1-11 years), youths (12-17 years) and adults (18+ years). 4 Categories of questions were asked: 'demographic characteristics', 'complaints and symptoms', 'lifestyle and knowledge' and 'visiting the dentist'. Regression analyses were performed to see which demographic factors influenced oral health. Of the respondents, 42% of the children, 57% of the youths and 86% of the adults reported at least one oral complaint or symptom. Of them 42% of the children, 59% of the youths and 53% of the adults followed the basic recommendation to brush their teeth twice a day. Of those questioned, 45% of the children, 48% of the youths and 28% of the adults went to a dentist for check-ups. When these results are compared to the rest of the Dutch population, asylum seekers scored worse in all categories.

Significant salivary changes in relation to oral mucositis following autologous hematopoietic stem cell transplantation.

The aim of this multicentre, longitudinal study was to determine salivary changes in relation to oral mucositis (OM) in multiple myeloma patients following high-dose melphalan and autologous hematopoietic stem cell transplantation (ASCT). Unstimulated and stimulated whole-mouth saliva samples (UWS and SWS) were collected before ASCT, 1×/wk during the hospitalisation phase, and 3 and 12 months post-ASCT. During the hospitalisation period OM was scored 3×/wk (WHO system). Flow rate, pH, total protein concentration (Nanodrop), albumin, lactoferrin, neutrophil defensin-1 (HNP1), total IgA and S100A8/A9 (ELISA) were determined. Mixed models were used to evaluate differences between ulcerative (u)OM (≥2 WHO, n = 20) and non-uOM (n = 31) groups. Until 18 days after ASCT, flow rate, pH, total IgA and HNP1 levels decreased in UWS and/or SWS, while log lactoferrin levels were significantly increased (UWS: p = 0.016 95% CI [0.36, 3.58], SWS: p < 0.001 95% CI [1.14, 3.29]). Twelve months post-ASCT, salivary protein levels were similar to baseline except for log total IgA, which was higher (UWS: p < 0.001 95% CI [0.49, 1.29], SWS: p < 0.001 95% CI [0.72, 1.45]). No differences between uOM and non-uOM groups were observed. Changes in salivary proteins indicated an inflammatory reaction in salivary glands coinciding with mucosal and systemic reactions in response to high-dose melphalan.

[The anticaries effect of antibacterial bonding in vitro is lost with aging]. / Het cariësremmende effect van antibacteriële bonding in vitro gaat verloren door veroudering.

This in vitro study investigated whether aging of restorative materials influences secondary caries development. The research question was whether antibacterial bonding maintained its effectiveness after aging. 60 enamel-dentine blocks were restored using 3 different restorative materials (n = 20 per material): composite with conventional bonding, composite with antibacterial bonding and amalgam. Half of the samples in each group (n = 10) were artificially aged through exposure to a sucrose biofilm model. Lesion depth was subsequently measured using transversal microradiography. Aging led to deeper lesions in the composite with antibacterial bonding group (CAB), compared to fresh samples. These fresh samples showed lesions less deep than fresh samples of composite with conventional bonding. After aging, this effect was absent. Within the limitations of this short-term in vitro study, it can be concluded that aging of restorative materials can influence caries progression. Antibacterial bonding materials lose their effectiveness over time.

[Risk factors for class II dental restoration survival:a practice-based study]. / Risicofactoren voor klasse II-restauratieoverleving: een praktijkgebaseerd onderzoek.

The aim of this practice-based cohort study was to determine the performance and influence of possible variables in class II restorations related to practice, patient, tooth, and restoration. To do this, electronic patient files from 11 general practices in the Netherlands were collected, and 31,472 restorations placed between January 2015 and October 2017 were analysed. The observation time of restorations varied from 0 to 2.7 years, resulting in a mean annual failure rate (AFR) of 7.8% at 2 years. However, wide variation in AFRs existed among the operators, varying between 3.6% and 11.4%. An excess of patient-related variables, such as age, general health, periodontal status, caries risk and the presence of parafunctional habits and tooth or restoration-related factors, increases the risk of reintervention. Restorations placed due to fracture were more prone to fail than restorations placed due to caries. This study demonstrated that a wide variety of risk factors on the practice, patient, and tooth levels influences the survival of class II restorations.

The effect of occlusal loading on cervical gap deformation: A 3D finite element analysis.

OBJECTIVES: Secondary caries can be accelerated by hydrodynamic flow in a gap between the tooth and restorative material. This study investigated whether occlusal loading can lead to increased hydrodynamic flow by deforming a gap between tooth and restorative material. METHODS: 3D finite element analysis was employed to model a molar containing a restoration with an interfacial gap. The model was loaded using direct cusp-to-restoration contact and using a rubber tube model simulating a food bolus. The object exerting pressure was moved across the molar from buccal to lingual side. The applied forces were 50, 100, 200 and 400N. The elastic modulus of the restoration material was varied between 5, 10, 15.9 and 25GPa to resemble different kinds of composite. The primary outcome parameter was the volume of the gap under occlusal pressure. RESULTS: Occlusal loading resulted in deformation of the gap area. Maximum deformation was seen when loading was applied in the middle of the restoration. Higher forces and lower restoration stiffness led to more deformation of the gap. Maximum deformation with a force of 100N and composite modulus of 15.9GPa was -0.0083mm3 (1.12%). SIGNIFICANCE: Deformation of the gap between tooth and restorative material could lead to increased hydrodynamic flow and faster secondary caries lesion formation. The measured deformation is small. Further research needs to show whether gap compression through occlusal loading affects secondary caries formation to a clinically relevant degree.

[Cup-shaped tooth wear defects: more than erosive challenges?] / Komvormige defecten in occlusale vlakken van molaren: meer dan alleen erosieve belasting?

The underlying mechanism of the development of cups and grooves on occlusal tooth surfaces is still unclear. The aim of this study was to evaluate factors contributing to in-vitro cup formation, and to elucidate the clinical process. Extracted human molar teeth were exposed to acidic aqueous solutions at pH of 4.8 and 5.5 in combination with different loading conditions: no load (0N, control), 30N or 50N. Before and after 3 months exposure, the samples were scanned using a non-contact profilometer. A statistically significant difference between a loading of 0N and 50N was found at pH 4.8 (p < 0.002). Cup shaped lesions had formed only at pH of 4.8, in the 30N and 50N groups. The study showed that a cup can arise fully in enamel and that this requires simultaneous acidic and mechanical loading.

Risk Factors for Dental Restoration Survival: A Practice-Based Study.

To improve patient dental care, it is necessary to identify possible risk factors for the failing of restorations. This practice-based cohort study investigated the performance and influence of possible risk factors at the level of the practice, patient, tooth, and restoration on survival of direct class II restorations. Electronic patient files from 11 Dutch general practices were collected, and 31,472 restorations placed between January 2015 and October 2017 were analyzed. Kaplan-Meier statistics were performed; annual failure rates (AFRs) were calculated; and variables were assessed by multivariable Cox regression analysis. The observation time of restorations varied from 0 to 2.7 y, resulting in a mean AFR of 7.8% at 2 y. However, wide variation in AFRs existed among the operators, varying between 3.6% and 11.4%. A wide range of patient-related variables is related to a high risk for reintervention: patient age (elderly: hazard ratio [HR], 1.372), general health (medically compromised: HR, 1.478), periodontal status (periodontal problems: HR, 1.207), caries risk and risk for parafunctional habits (high: HR, 1.687), restorations in molar teeth (HR, 1.383), restorations placed in endodontically treated teeth (HR, 1.890), and multisurface restorations (≥4 surfaces: HR, 1.345). Restorations placed due to fracture were more prone to fail than restorations placed due to caries. When patient-related risk factors were excluded, remaining risk factors considerably changed in their effect and significance: the effect of operator, age of the patient, and endodontic treatment increased; the effect of the diagnosis decreased; and the socioeconomic status became significant (high: HR, 0.873). This study demonstrated that a wide variation of risk factors on the practice, patient, and tooth levels influences the survival of class II restorations. To provide personalized dental care, it is important to identify and record potential risk factors. Therefore, we recommend further clinical studies to include these patient risk factors in data collection and analysis.

A threshold gap size for in situ secondary caries lesion development.

OBJECTIVES: This study investigated the influence of very small gaps in secondary caries (SC) development and additionally linked the threshold gap size with the caries activity level from volunteers. METHODS: For 21 days, 15 volunteers wore a modified occlusal splint loaded with dentin-composite samples restored with different interfaces: bonded (B = samples restored with complete adhesive procedure), no-bonded (NB = restored with composite resin without adhesive procedure), and 30, 60 and 90 µm (no adhesive procedure and with intentional gap). The splint was dipped in a 20% sucrose solution (10 min) 8 x per day. Samples were imaged with transversal wavelength independent microradiography (T-WIM) and lesion depth and mineral loss were calculated. Average wall lesion depth from each volunteer was determined and according to the values the volunteers were grouped as high, mid and low caries activity levels. RESULTS: No wall lesion formation was observed in B and NB groups. In general, intentional gaps led to SC lesion depth progression independent of caries activity level of volunteers. No substantial wall lesions were found for two volunteers. A trend for deeper lesion in larger gaps was observed for the high activity group. CONCLUSION: Very small gaps around or wider than 30 µm develop SC independent of the caries activity level of the patient and SC wall lesion progression seemed to be related to individual factors even in this standardized in situ model. SIGNIFICANCE: Independently of caries activity level of the patient, the threshold gap size for secondary caries wall lesion seems to be 30 µm at most.

[Results of the assessment procedure for dentists with a foreign degree in the Netherlands]. / Resultaten van de toetsingsprocedure van tandartsen met een buitenlands diploma.

During the period from 1 January 2007 to 1 January 2017, 138 dentists with a foreign dental degree (obtained outside the European Economic Area or Switzerland) who wanted to practice dentistry in the Netherlands have undertaken the assessment procedure to obtain a certificate of professional competence. The procedure comprises a Dutch language proficiency and communications test, followed by tests of competence specific to the dental profession. For 68 dentists (49%), no deficiencies in knowledge or skills were identified. They could register in the BIG-register [for healthcare professionals] for the supervisory period. For 49 (36%), the deficiencies could be eliminated with specific training. In the case of 21 dentists (15%), training was not possible. The number of dentists from this group who were enrolled in the BIG-register in 2017 was determined. On the reference date, 100 dentists (73%) were enrolled. Of the 49 dentists who were permitted to participate in a specific educational programme, 48 had started such a programme: 38 had completed it by 2017, 9 are still actively involved, and 1 stopped the programme. If they complete the programme, the number of dentists who have been enrolled in the BIG-register after [successfully] finishing the assessment procedure could rise to 115 (83%).

[Preventive dentistry 10. Erosive tooth wear]. / Preventieve tandheelkunde 10. Erosieve gebitsslijtage.

Erosive tooth wear has recently been at the centre of attention and its prevalence of erosive tooth wear among adolescents in the Netherlands appears to be rising. The multifactorial nature of the aetiology of the condition makes it difficult to identify the relevant causal factors, both in individual cases and within the general population. Preventive intervention is indicated in those cases where (active) erosive tooth wear is diagnosed. Early diagnosis is important, especially in younger patients. Preventive measures, such as dietary advice and the use of fluoride, are recommended but the scientific evidence for their effectiveness is still limited. In cases where acid reflux disease is the cause, treatment with medicines can have the effect of reducing the progression of tooth wear. Recognising a non-active condition, for example after successful preventive treatment, is difficult, but will be supported with digital methods in the near future.

Secondary caries development and the role of a matrix metalloproteinase inhibitor: A clinical in situ study.

OBJECTIVES: This in situ study aimed to investigate whether the dentin treatment with MMPs inhibitor (CHX 2%) could influence the development of secondary caries wall lesions in different dentin-composite interfaces. MATERIAL AND METHODS: For 21 days, 15 volunteers wore a modified-occlusal splint loaded with dentin-composite samples treated or not with CHX and restored according 4 different interface conditions: Bonding (B = samples restored with complete adhesive procedure), no bonding (NB = restored with composite resin without adhesive procedure), 100 µm (no adhesive procedure and with intentional gap) and 100 µm + B (adhesive material on composite side and intentional gap). Eight times per day, the splint with samples was dipped in a 20% sucrose solution for 10 min. Before and after caries development, samples were imaged with T-WIM and lesion depth (LD) and mineral loss (ML) were calculated. RESULTS: Linear mixed effect analysis showed that dentin treatment with CHX did not significantly affect the caries lesion progression (LD and ML; p ≤ 0.797). Dentin wall lesions were observed in the 100 µm and 100 µm + B groups independently of MMP inhibitor treatment. CONCLUSION: The treatment of dentin with MMP inhibitor was not able to slow down the secondary caries wall lesion development in this in situ study. SIGNIFICANCE: The dentin treatment with 2% CHX did not prevent secondary caries wall lesion initiation.

Clinical performance of full rehabilitations with direct composite in severe tooth wear patients: 3.5 Years results.

OBJECTIVES: To evaluate the mid-term clinical performance of direct composite restorations placed in patients with pathological tooth wear needing full rehabilitation with an increase of vertical dimension of occlusion. METHODS: In a prospective trial 34 patients (34.0 ±â€¯8.4 years; 25 males, 9 females) were treated with a minimal invasive additive technique using composite restorations. The restorative treatment protocol was to provide all teeth with composite build-up restorations in an increased vertical dimension of occlusion (VDO) using the DSO-technique. Recall appointments were planned after 1 month, 1 and 3 years after treatment. Restorations were scored for clinically acceptability (FDI-criteria) and scores 4 and 5 were recorded as clinically unacceptable. Frequencies of failures and Kaplan Meier survival curves are presented and effect of relevant variables was calculated with a multifactorial Cox regression (p < 0.05). RESULTS: 1256 Restorations were placed, 687 anterior, 324 premolar, and 245 molar restorations. After a mean observation time of 39.7 months a total of 69 failures were observed, of which 61 restorations were repaired (score 4) and 8 were replaced (score 5). Most common reasons for failure were (chip) fractures (n = 43) and caries (n = 11). Placement of anterior restorations in two sessions led to significant 4.6 times more failures then placed in one session. CONCLUSIONS: In patients with severe tooth wear a full rehabilitation, in an increased vertical dimension of occlusion, direct composite resin restorations show a 94.8% success and 99.3% survival rate after a period of 3.5 years.

In vitro biofilm models to study dental caries: a systematic review.

The aim of this systematic review is to characterize and discuss key methodological aspects of in vitro biofilm models for caries-related research and to verify the reproducibility and dose-response of models considering the response to anti-caries and/or antimicrobial substances. Inclusion criteria were divided into Part I (PI): an in vitro biofilm model that produces a cariogenic biofilm and/or caries-like lesions and allows pH fluctuations; and Part II (PII): models showing an effect of anti-caries and/or antimicrobial substances. Within PI, 72.9% consisted of dynamic biofilm models, while 27.1% consisted of batch models. Within PII, 75.5% corresponded to dynamic models, whereas 24.5% corresponded to batch models. Respectively, 20.4 and 14.3% of the studies reported dose-response validations and reproducibility, and 32.7% were classified as having a high risk of bias. Several in vitro biofilm models are available for caries-related research; however, most models lack validation by dose-response and reproducibility experiments for each proposed protocol.

Longevity of Anterior Composite Restorations in a General Dental Practice-Based Network.

This practice-based study investigated the performance of a large set of anterior composite restorations placed by a group of 24 general practices. Based on data from electronic patient files, the longevity of 72,196 composite restorations was analyzed, as placed in 29,855 patients by 47 general dental practitioners between 1996 and 2011. Annual failure rates (AFRs) were calculated, and variables associated with failure were assessed by multivariate Cox regression analysis with shared frailty for 2 age groups (5 to 24 y and ≥25 y). The observation time of restorations varied from 2 wk to 13 y, with a mean of 4.8 y, resulting in a mean AFR of 4.6% (95% confidence interval [95% CI], 4.5% to 4.6%) at 5 y. Among dentists, a relevant variation in clinical performance of restorations was observed, with an AFR between 2% and 11%. The risk for restoration failure increased in individuals up to 12 y old, having a 17% higher risk for failure when compared with the age group of 18 to 25 y (hazard ratio, 1.17; 95% CI, 1.03 to 1.34), and for the age group >65 y, having a 81% higher risk for failure when compared with 25 to 35 y (hazard ratio, 1.81; 95% CI, 1.66 to 1.98). In both multivariate models, there was a difference in longevity of restorations for different teeth in the arch, with fillings in central incisors being the most prone to failure and replacement. It was concluded that anterior composite restorations placed by general dental practitioners showed an adequate clinical performance, with a relevant difference in outcome among operators.

[Preventive dentistry 5. Secondary caries]. / Preventieve tandheelkunde 5. Secundaire cariës.

Secondary caries is reported as one of the most important reasons for replacing restorations. The patient's general caries risk plays an important role in the development of secondary caries. The connection, at the patient level, between various factors, the risk of caries and restoration factors, such as the presence of a gap and the kind of restoration material, deserves additional investigation. The minimum gap width in which secondary caries can develop is most likely less than 100 µm and could depend on the patient's caries risk. Composite restorations seem more susceptible to secondary caries than amalgam restorations in patients with high caries risk. So far, there is no unambiguous explanation for this difference. The prevention of secondary caries is comparable to that of primary caries and stresses the importance of fluoride, diet and oral hygiene.