Posterior composites and new caries on adjacent surfaces - any association? Longitudinal study with a split-mouth design

Preventing proximal enamel caries in neighboring tooth with glass ionomer cement restoration and silver diamine fluoride pretreatment

OBJECTIVE

To investigate caries preventive effects of 38 % silver diamine fluoride (SDF) pretreatment on neighboring tooth proximal to glass ionomer cement (GIC), including conventional GIC (CGIC) and resin-modified GIC (RMGIC) restorations in an in vitro model.

METHODS

HUMAN TOOTH BLOCKS WERE RESTORED WITH: SDF+CGIC (Group 1), CGIC (Group 2), SDF+RMGIC (Group 3) or RMGIC (Group 4). Enamel specimen simulating proximal surface of neighboring tooth was placed in proximity to the restorations. The specimen underwent cariogenic challenge with cross-kingdom biofilm of Streptococcus mutans, Lacticaseibacillus casei and Candida albicans. After cariogenic challenge, the biofilm's growth kinetics, viability, and morphology were evaluated by propidium monoazide-quantitative polymerase chain reaction (PMA-qPCR), confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM), respectively. The enamel lesion depth, surface morphology and crystal characteristics were determined by micro-computed tomography (micro-CT), SEM and X-ray diffraction (XRD), respectively.

RESULTS

PMA-qPCR demonstrated lower microbial growth in Group 1 and 3 compared with Group 2 and 4 (p < 0.05). CLSM showed the dead-to-live ratio in Groups 1-4 were 1.15±0.12, 0.53±0.13, 1.10±0.24 and 0.63±0.10, respectively (Group 1,3 > 2,4, p < 0.05). SEM revealed Groups 1 and 3 had scattered biofilm whereas Group 2 and 4 had confluent biofilm. Micro-CT showed the enamel lesion depths (µm) were 98±9, 126±7, 103±6 and 128±7 for Group 1 to 4, respectively (Group 1,3 < 2,4, p < 0.05). SEM revealed oriented and ordered enamel prismatic patterns in Group 1 and 3, not in Group 2 and 4. XRD showed the reflections of hydroxyapatite in Groups 1 and 3 were sharper than Groups 2 and 4.

CONCLUSION

SDF pretreatment enhances the preventive effect of GIC on proximal enamel surface on neighboring tooth through inhibiting cariogenic biofilm, reducing enamel demineralization and promoting enamel remineralization.

CLINICAL SIGNIFICANCE

SDF pretreatment of GIC restorations can help prevent caries on neighboring teeth, particular for patients with high caries risk.

Procedure time and filling quality for bulk-fill base and conventional incremental composite techniques-A randomised controlled in vitro trial

OBJECTIVES

The aims of this randomised controlled laboratory trial were to determine the procedure time and immediate quality (surface porosity and marginal gaps) of fillings placed using the bulk-fill base technique and the conventional incremental technique in simulated clinical settings.

METHODS

Forty-two dentists and dental students were randomly allocated to use either the bulk-fill base technique or the conventional incremental technique to fill an identical class II disto-occlusal cavity in a maxillary left first molar typodont tooth. We recorded the time the participants used to fill the cavity and evaluated the surface porosity and marginal gaps on the approximal surfaces of the fillings using a stereomicroscope and specific probes according to the FDI criteria for restoration evaluation. Data were analysed using the Mann-Whitney U, Kruskal-Wallis, and chi-square tests.

RESULTS

The median time ± interquartile range was 186 ± 80 s for the bulk-fill base technique and 463 ± 156 s for the conventional incremental technique (p < 0.001). The quality of the fillings was better for the bulk-fill base technique than for the conventional incremental technique (X2 = 9.5, p = 0.002). Neither operator experience nor the usual technique of choice were associated with the procedure time or the quality of the fillings.

CONCLUSIONS

Compared to the conventional incremental technique, the use of the bulk-fill base technique shortened the time to fill a cavity by 59.8 % or 4 min and 36 s, and it improved the immediate surface and marginal quality of the fillings, regardless of the operator's experience or technique preference.

CLINICAL SIGNIFICANCE

The use of the bulk-fill base technique instead of the conventional incremental technique leads to significant time-savings when placing large class II composite fillings. Additionally, the use of the bulk-fill base technique instead of the conventional incremental technique improves the immediate quality of large class II composite fillings.

Current Strategies to Control Recurrent and Residual Caries with Resin Composite Restorations: Operator- and Material-Related Factors

This review addresses the rationale of recurrent and/or residual caries associated with resin composite restorations alongside current strategies and evidence-based recommendations to arrest residual caries and restrain recurrent caries. The PubMed and MEDLINE databases were searched for composite-associated recurrent/residual caries focusing on predisposing factors related to materials and operator’s skills; patient-related factors were out of scope. Recurrent caries and fractures are the main reasons for the failure of resin composites. Recurrent and residual caries are evaluated differently with no exact distinguishment, especially for wall lesions. Recurrent caries correlates to patient factors, the operator’s skills of cavity preparation, and material selection and insertion. Material-related factors are significant. Strong evidence validates the minimally invasive management of deep caries, with concerns regarding residual infected dentin. Promising technologies promote resin composites with antibacterial and remineralizing potentials. Insertion techniques influence adaptation, marginal seal, and proximal contact tightness. A reliable diagnostic method for recurrent or residual caries is urgently required. Ongoing endeavors cannot eliminate recurrent caries or precisely validate residual caries. The operator’s responsibility to precisely diagnose original caries and remaining tooth structure, consider oral environmental conditions, accurately prepare cavities, and select and apply restorative materials are integral aspects. Recurrent caries around composites requires a triad of attention where the operator’s skills are cornerstones.

Does the Behavior of Pediatric Patients towards Dental Treatment Influence the Pattern of Adjacent (Sound, Decayed, and Filled) Proximal Surfaces in Primary Molars?

This retrospective study aimed to investigate the influence of patient behavior toward dental treatment on the presence of adjacent (sound, decayed, or filled) proximal surfaces in the primary molars. The study included a records review of 2226 pediatric patients. Records were eligible if the patients were in primary or mixed dentition, and if they included a complete set of bitewings and periapical intraoral radiographs of all their primary molars. Four calibrated reviewers used intraoral radiographs to record the sound, decayed, and filled proximal distal surfaces of the first primary molars and the mesial surfaces of the second primary molars. Demographical variables were reported from patients’ medical records including gender, age, medical history, nationality, and patient behavior. Patients’ behaviors were evaluated using Frankl’s Behavior Rating Scale. The Pearson correlation was used to test the association between the sound, decayed, and filled distal surfaces of the first primary molars and the mesial surface of the second primary molar. High correlations of ≥0.6 were further tested in simple and multiple linear regression models to test the influence of patients’ behaviors on these correlations after adjusting for demographical factors. All tests were performed at 5% significance level A. A total of 1194 records met the inclusion criteria and were analyzed. There was a high positive correlation between the sound, decayed, and filled distal surfaces of the first primary molar and similar surfaces on the mesial of the second primary molars (0.66, 0.61, and 0.60, respectively). Compared to cooperative patients, the adjusted estimate of the mean decayed mesial surface of the second primary molar increased significantly for non-cooperative patients by 0.1 (95% CI = 0.16–0.53). On the contrary, the adjusted estimate of the mean sound mesial surfaces of the second primary molars decreased significantly by 0.09 for non-cooperative patients, compared to those who were cooperative (95% CI = −0.52–−0.15). Patient cooperation did not significantly influence the mean of the filled mesial surfaces of the second primary molars (adjusted B = 0.01, 95% CI = −0.05–0.09). Educating parents and clinicians about the influence of children’s behaviors on oral health is highly encouraged to improve treatment outcomes and reduce the progression of dental caries. The implementation of specific behavior management techniques is also important to reduce dental fear and anxiety.

Dental caries in children and adolescents with juvenile idiopathic arthritis and controls: a multilevel analysis

Background

Optimal utilization of dental caries data is crucial in epidemiological research of individuals with juvenile idiopathic arthritis (JIA). The aims were to: explore whether caries is more prevalent among children and adolescents with JIA compared to controls; examine presence of caries according to JIA group, socio-behavioral and intraoral characteristics, and the extent to which surface-specific caries varies between and within individuals; assess whether surface-specific caries varies according to JIA group and dentition; and investigate whether disease-specific clinical features of JIA are associated with presence of caries.

Methods

In this comparative cross-sectional study, calibrated dentists examined index teeth (primary 2. molars, 1. permanent molars) of 4–16-year-olds with JIA (n = 219) and matched controls (n = 224), using a detailed caries diagnosis system (including enamel caries). JIA-specific characteristics were assessed by pediatric rheumatologists and socio-behavioral information collected by questionnaires. Multilevel mixed-effect logistic regressions reporting odds ratios (OR) with 95% confidence interval (CI) were applied (caries at surface level as outcome variable). Potential confounders were adjusted for, and the effect of dependency of surface-specific caries data was estimated by calculating intra-class correlation coefficients (ICC).

Results

At individual level, no significant difference in caries prevalence was found between individuals with JIA and controls, regardless of inclusion of enamel caries. Proportion of enamel lesions exceeded dentine lesions. JIA was not associated with presence of caries, but in both groups, low maternal educational level was associated with presence of caries (OR: 2.07, 95% CI: 1.24–3.46). Occlusal and mesial surfaces, compared to buccal surfaces, had generally higher OR according to presence of caries than distal and lingual surfaces (ICC = 0.56). Surface-specific caries in the permanent dentition differed significantly according to group affiliation. Some JIA disease-specific variables were suggested to associate with presence of caries.

Conclusions

No overall difference in caries prevalence between individuals with JIA and controls was observed, but for both groups, low maternal educational level and tooth surface associated with presence of caries. Associations between JIA disease-specific variables and presence of caries cannot be excluded. Due to predominance of enamel lesions, the potential of preventative dental strategies is considerable.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-021-01758-y.

Microbial biogeography and ecology of the mouth and implications for periodontal diseases

In humans, the composition of microbial communities differs among body sites and between habitats within a single site. Patterns of variation in the distribution of organisms across time and space are referred to as "biogeography." The human oral cavity is a critical observatory for exploring microbial biogeography because it is spatially structured, easily accessible, and its microbiota has been linked to the promotion of both health and disease. The biogeographic features of microbial communities residing in spatially distinct, but ecologically similar, environments on the human body, including the subgingival crevice, have not yet been adequately explored. The purpose of this paper is twofold. First, we seek to provide the dental community with a primer on biogeographic theory, highlighting its relevance to the study of the human oral cavity. We summarize what is known about the biogeographic variation of dental caries and periodontitis and postulate that disease occurrence reflects spatial patterning in the composition and structure of oral microbial communities. Second, we present a number of methods that investigators can use to test specific hypotheses using biogeographic theory. To anchor our discussion, we apply each method to a case study and examine the spatial variation of the human subgingival microbiota in 2 individuals. Our case study suggests that the composition of subgingival communities may conform to an anterior-to-posterior gradient within the oral cavity. The gradient appears to be structured by both deterministic and nondeterministic processes, although additional work is needed to confirm these findings. A better understanding of biogeographic patterns and processes will lead to improved efficacy of dental interventions targeting the oral microbiota.

Clinical accuracy data presented as natural frequencies improve dentists' caries diagnostic inference: Evidence from a randomized controlled trial

BACKGROUND

The authors assessed whether dentists' diagnostic inferences differ when test accuracy information is communicated using natural frequencies versus conditional probabilities.

METHODS

A parallel, randomized controlled trial with dentists was carried out in Rio de Janeiro, Brazil. The dentists received a question on the probability of a patient having interproximal caries, given a positive bite-wing radiograph. This question was asked using information that was formulated into either natural frequencies or conditional probabilities.

RESULTS

Only 14 (13.9%) of the dentists gave the correct answer; 13 in the natural frequencies group, and 1 in the conditional probabilities group (P < .001). There were 7 nearly correct answers in the natural frequencies group and none in the conditional probabilities group (P = .005).

CONCLUSIONS

Representing diagnostic test accuracy in natural frequencies substantially helped dentists make diagnostic inferences. Nearly twice as many dentists overestimated the presence of interproximal caries when given information in conditional probabilities.

PRACTICAL IMPLICATIONS

Our study findings show information shared using natural frequencies may be more accurately interpreted by dentists than that based on conditional probabilities. Patients will probably receive different standards of care depending on the format in which dentists receive diagnostic test accuracy information.

Need of non-operative caries treatment in 16-year-olds from Northern Norway

AIM

To assess the prevalence of proximal enamel lesions, the need for non-operative caries treatment and the quality of dental restorations in 869 students aged 16 years from Northern Norway.

METHODS

All first year upper secondary school students in Tromsø and Balsfjord municipalities were invited to participate in an oral- and general health project (Fit Futures). The attendance rate was 90%, and all subjects born in 1994 (449 males and 420 females) were included in the present study. Dental caries was registered according to a 5-graded scale (1-2 = enamel lesions; 3-5 = dentinal lesions). Scores from 1 to 4 were used to register the quality of restorations (1 = good; 2 = acceptable; 3 = poor; 4 = unacceptable).

RESULTS

Only 6% of the 16-year-olds were completely caries-free. There were 84% of the participants with proximal enamel lesions. A majority of them had either previously restored teeth (35%) or both restored teeth and untreated dentinal caries lesions (34%). When using the D-value of the DMFS-index as a diagnostic criterion, 39% of the participants were in need of restorative treatment. When proximal enamel lesions were included in the diagnosis, the number of participants in need of restorative and/or non-operative caries treatment was 85%. Over 1/3 of the participants presented with at least one restoration below an acceptable quality level.

CONCLUSIONS

Dental caries is still a major health problem affecting the total teenage population. A non-operative treatment strategy should be considered relevant in order to reduce the need for restorative treatment.