Micro-invasive interventions for managing non-cavitated proximal caries of different depths: a systematic review and meta-analysis

Equivalence study of the resin-dentine interface of internal tunnel restorations when using an enamel infiltrant resin with ethanol-wet dentine bonding

This preregistered ex vivo investigation examined the dentinal hybrid layer formation of a resinous infiltrant (Icon), with reference to both thickness (HLT) and homogeneity when combined with modified tunnel preparation (occlusal cavity only) and internal/external caries infiltration. The adhesives Syntac and Scotchbond MP were used as controls (Groups 1 and 3) or in combination with Icon (Groups 2 and 4). A split-tooth design using healthy third molars from 20 donors resulted in 20 prepared dentine cavities per experimental group. The cavity surfaces (n = 80) were etched (37% H3PO4), rinsed, and air-dried. Rewetting with ethanol was followed by application of the respective primers. After labeling with fluorescent dyes, either Syntac Adhesive/Heliobond or Scotchbond MP Adhesive was used alone or supplemented with Icon. HLT, as evaluated by scanning electron microscopy, did not significantly differ (P > 0.05), and confocal laser scanning microscopy revealed homogeneously mixed/polymerized resin-dentine interdiffusion zones in all groups. Icon can be successfully integrated into an ethanol-wet dentine bonding strategy, and will result in compact and homogeneous hybrid layers of comparable thickness considered equivalent to the non-Icon controls, thus allowing for preservation of the tooth's marginal ridge and interdental space in the case of internal/external infiltration of proximal caries.

Evaluation of the effectiveness of prophylactic sealing of pits and fissures of permanent teeth with fissure sealants - umbrella review

BACKGROUND

Tooth decay is an infectious disease which, in its initial phase, leads to the formation of cavities in the teeth through decalcification of the enamel and local tissue destruction. In addition to proper oral hygiene, prophylactic sealing of fissures and cavities with a sealant is a method of preventing the development of caries. The aim of this study is to summarise the effectiveness of fissure sealing of permanent teeth with fissure sealants compared to other preventive methods or no intervention.

METHOD

An umbrella review was carried out to achieve the purpose of our study. Searches were performed in Medline (via PubMed), Embase (via OVID), and Cochrane Library databases. Quality assessment of the included studies was performed using the AMSTAR2 tool. In addition, a manual search for recommendations/clinical practice guidelines on dental prophylaxis was performed.

RESULTS

204 publications were identified, of which 15 met the inclusion criteria. Based on the results of 3 systematic reviews, there was a statistically significant reduced odds of caries occurrence or development with prophylactic sealing of permanent teeth compared with no intervention - depending on the review and follow-up period odds ratio (OR) ranged from 0.06 [95%CI: (0.01-0.32)] to 0.28 [95%CI: (0.20-0.38)]. In the eight systematic reviews that analysed different sealants, there were no statistically significant differences between the types of materials used for prophylactic tooth sealing. For systematic reviews comparing the efficacy of fissure sealants with fluoride varnish, three reported no statistically significant difference in the efficacy of caries incidence, with only one systematic review based on 1 RCT finding a statistically significant difference in favour of fissure sealants.

CONCLUSION

Compared to the no intervention, dental sealing is an effective method for the prevention of dental caries. However, it is not possible to conclude conclusively which type of sealant and which of the available prophylactic methods is more effective in preventing caries.

Effect of Light-Curable Resin-Modified Glass Ionomer Varnish on Non-Cavitated Proximal Caries Lesions in Primary Molars: A Randomized Controlled Trial

The purpose of this study was to radiographically and clinically assess, after six and twelve months, the additive effect of light-curable resin-modified glass ionomer (LCRMGI) varnish on preventive standard-of-care measures (sodium fluoride varnish, oral hygiene instructions, and dietary counseling) for the treatment of non-cavitated proximal carious lesions in primary molars. This prospective, split-mouth, randomized clinical trial recruited 5-8-year-old children with at least one pair of bilateral non-cavitated proximal carious lesions in the enamel or outer third of the dentin. The lesions were randomized into one of two groups: experimental (which received LCRMGI varnish with the preventive standard-of-care measures) or control (which received the preventive standard-of-care measure). A total of 47 out of 53 participants, with 70 out of 80 pairs, completed the study. Radiographically, lesions in the experimental groups were more likely to regress after six (OR = 3.25) and twelve months (OR = 2.67), but it was not statistically significant (p = 0.052 and p = 0.055, respectively). Clinically, the experimental group showed significantly higher regression rates than the control group after six and twelve months (p = 0.041 and p = 0.003, respectively). The LCRMGI varnish demonstrated promising potential as an adjuvant to preventive standard-of-care measures in promoting regression and inhibiting the progression of non-cavitated proximal carious lesions.

The revolutionary evolution in carious lesion management

Contemporary paradigms of dental caries management focus on the biological approaches to treating the disease and its principal symptom, the carious lesion. This narrative review traces the evolution of carious lesion management from the operative and invasive approaches of G. V. Black's era to the current period of minimally invasive biological approaches. The paper explains the rationale for adopting biological approaches to dental caries management and lists the five core principles of this management approach. The paper also details the aims, features, and the most recent evidence base for the different biological carious lesion management approaches. Based on current practice guidelines, collated clinical pathways for lesion management are also presented in the paper to aid clinicians in their decision-making. It is hoped that the biological rationale and evidence summarized in this paper will bolster the shift to modern biological carious lesion management approaches among dental practitioners.

Resin Infiltration of Non-Cavitated Proximal Caries Lesions in Primary and Permanent Teeth: A Systematic Review and Scenario Analysis of Randomized Controlled Trials

The present study aimed to meta-analyze and evaluate the certainty of evidence for resin infiltration of proximal carious lesions in primary and permanent teeth. While resin infiltration has been shown efficacious for caries management, the certainty of evidence remains unclear. The protocol was registered with PROSPERO (CRD42018080895), and PRISMA guidelines have been followed. The databases PubMed, Embase, and Cochrane CENTRAL were systematically screened, complemented by hand searches and cross-referencing. Eleven relevant articles were identified and included, i.e., randomized controlled trials (RCTs) comparing the progression of resin infiltrated proximal caries lesions (combined with non-invasive measures) in primary or permanent teeth with non-invasive measures. Random-effects meta-analyses and trial sequential analyses (TSA) were performed for per-protocol (PP), intention-to-treat (ITT), and best/worst case (BC/WC) scenarios. Six included trials assessed lesions in permanent teeth and five trails assessed lesions in primary teeth. The trials had a high or unclear risk of bias. Risk of caries progression was significantly reduced for infiltrated lesions in the PP, ITT, and BC scenarios in both permanent teeth and primary teeth, but not in the WC scenario. According to the TSA, firm evidence was reached for all of the scenarios except the WC. In conclusion, there is firm evidence for resin infiltration arresting proximal caries lesions in permanent and primary teeth.

Resin Infiltration of Non-Cavitated Enamel Lesions in Paediatric Dentistry: A Narrative Review

The resin infiltration (RI) technique was introduced as one of the minimal intervention dentistry strategies in addressing dental caries among the paediatric population. This technique used the low-viscosity resin monomer to infiltrate the non-cavitated carious lesion and other developmental enamel porosities, thus allowing the conservation of the tooth structure. This narrative review aims to explore the value of RI in Paediatric Dentistry. Through our search of the literature, the development of the material, their clinical applications and shortcomings, as well as the innovation that has been carried out to improve the current RI, were discussed. There are number of high-level evidence supporting the use of RI in arresting non-cavitated proximal caries lesions in primary and permanent teeth, but its efficacy in managing anterior white spot lesions is still unclear. Limited penetration depth, not radiopaque and questionable long-term colour and material stability were among the limitation of the material. Various laboratory-based studies have been conducted to improve the current properties of RI. Nevertheless, RI has emerged as one of the important micro-invasive techniques in addressing non-cavitated and anterior white-spot enamel lesions in children and adolescents with great success.

The effect of minimally invasive treatments on enamel microhardness and resistance to further demineralization

Objectives: The present study aimed to compare microhardness of inactive proximal lesions treated by resin infiltration, Er:YAG laser + resin infiltration and Bioactive glass, and investigate the resistance of treated lesions to further demineralization challenge. Methods: In this in-vitro study, 30 human molars with inactive proximal lesions were selected and randomly divided into three groups of 10. In group 1 (resin infiltration), the lesions were treated by a resin infiltrant (Icon). In group 2, the surface was conditioned by an Er:YAG laser prior to resin infiltration. The specimens in group 3 were remineralized by bioactive glass. The treated specimens were kept in artificial saliva for 1 week and then immersed in a demineralization solution for 8 weeks. Surface microhardness was measured at baseline (T0), after remineralization (T1) and after exposure to the demineralization solution (T2), and the difference in microhardness between time points (ΔVHN) was calculated. Results: Microhardness after demineralization (T2) was significantly lower than those of other intervals (P0.05). The statistical analysis revealed no significant difference either in ΔVHNT1-T0 or in ΔVHNT2-T1 among the study groups (P>0.05) Conclusion: Pretreatment by the Er:YAG laser prior to resin infiltration was more effective that other treatments in enhancing microhardness and protecting the tooth against acidic challenge. However, the difference between groups did not reach a statistical significance, implying the need for further studies to achieve more conclusive results.

Effects of Alternative Solvents in Experimental Enamel Infiltrants on Bond Strength and Selected Properties

Objective. To evaluate different concentrations of solvents (tetrahydrofuran (THF) and dimethyl sulfoxide (DMSO) and monomers on the degree of conversion, microtensile bond strength, and mechanical properties of experimental resin infiltrants. Materials and Methods. Resin infiltrants were formulated and divided into eleven groups: (1) Icon, (2) 75% TEGDMA (T) +25% UDMA (U), (3) T +25% BIS-EMA (B), (4) T + U +0.5%DMSO, (5) T + U +5% DMSO, (6) T + U +0.5% THF, (7) T + U +5% THF, (8) T + B +0.5% DMSO, (9) T + B +5% DMSO, (10) T + B +0.5% THF, and (11) T + B +5% THF. One hundred and ten bovine mandibular incisors were sectioned, treated, and destined to the degree of conversion, tensile cohesive strength, microtensile bond strength, flexural strength, and elastic modulus. Data were submitted to one-way ANOVA and Tukey’s test ( $\alpha =0.05$ ). Results. The degree of conversion was lowest for T + B +5%THF (41.9%) and highest for T + U +5%THF (62.1%). In flexural strength and E-modulus, the T + B (96.5 MPa and 0.49 GPa) obtained the highest values and the lowest for T + U +5% DMSO (18.5 MPa and 9.7 GPa). Icon showed the highest bond strength (19.3 MPa) and cohesive strength (62.2 MPa), while T + U +5%DMSO (9.7 MPa) and T + B +5% DMSO (9.8 MPa) the lowest values and T + B +0.5% DMSO (12.3 MPa) the lowest cohesive strength. Conclusions. The addition of lower concentrations of DMSO or THF (0.5%) did not impair bond strength or significantly affect monomer conversion, but reduced the mechanical properties of resin infiltration.

In vitro effect of resin infiltrant on resistance of sound enamel surfaces in permanent teeth to demineralization

OBJECTIVE

To investigate the effect of resin infiltrant on resistance of sound permanent enamel surfaces to demineralization.

METHOD

Eighty healthy premolars were sectioned to obtain enamel blocks from the buccal surface. Specimens with baseline surface microhardness values of 320-370 were selected. The experimental group were treated with resin infiltrant, while the control group was not. Specimens from each group were artificially demineralized and the surface microhardness values were measured again. Confocal laser scanning microscopy was used to measure the depth of demineralization and detect the penetration ability of the resin infiltrant. The specimens were subjected to a simulated toothbrushing abrasion test. Scanning electron microscopy was used to observe changes in the surface morphology of specimens after each of these procedures.

RESULTS

No significant differences between the experimental and control groups were observed in the baseline microhardness values or in the experimental group after resin infiltration compared with the baseline conditions. After artificial demineralization, the microhardness value in the control group was significantly lower than that in the experimental group (266.0 (±34.5) compared with 304.0 (±13.0), P = 0.017). Confocal laser scanning microscopy results showed that the demineralization depth in the control group was significantly deeper than that in the experimental group (97.9 (±22.8) µm vs. 50.4 (±14.3) µm, P < 0.001), and that resin infiltrant completely penetrated the acid-etched demineralized area of the tooth enamel with a mean penetration depth of 31.6 (±9.0) µm. Scanning electron microscopy showed that the surface morphology was more uniform and smoother after simulated toothbrushing. The enamel surface structure was more severely destroyed in the control group after artificial demineralization compared with that of the experimental group.

CONCLUSION

Resin infiltrant can completely penetrate an acid-etched demineralized enamel area and improve resistance of sound enamel surfaces to demineralization. Our findings provide an experimental basis for preventive application of resin infiltrant to sound enamel surfaces to protect tooth enamel against demineralization.

Minimally Invasive Therapies for the Management of Dental Caries—A Literature Review

In recent years, due to a better understanding of the caries pathology and advances in dental materials, the utilization of non-invasive and minimally invasive techniques that delay/obviate the need for traditional restorations has started gaining momentum. This literature review focuses on some of these approaches, including fluoride varnish, silver diamine fluoride, resin sealants, resin infiltration, chemomechanical caries removal and atraumatic restorative treatment, in the context of their chemistries, indications for use, clinical efficacy, factors determining efficacy and limitations. Additionally, we discuss strategies currently being explored to enhance the antimicrobial properties of these treatment modalities to expand the scope of their application.

A retrospective clinical study on the resin infiltration of proximal caries lesions: the operator's effect

Purpose

This retrospective university-based study investigated the effect of operators’ training and previous experience on the success of resin infiltration (RI) in arresting proximal non-cavitated caries lesions in primary and permanent teeth.

Methods

Information was collected regarding RI of proximal non-cavitated caries lesions in primary and permanent teeth with a follow-up period up to 32 months. Factors investigated were: operators’ clinical experience and training, patient’s age, tooth, arch, mouth-side, surface treated, tooth separation, and baseline lesion depth. Kaplan–Meier survival and Cox regression analysis with shared frailty were used (α = 5%).

Results

A total of 130 proximal surfaces treated on 115 teeth of 43 children (11 ± 4.4 years) were evaluated. Survival of RI was 46% up to 32 months. Lesions treated by non-trained dentists were more likely-to-present progression than those performed by non-trained dental students under supervision (HR 2.41, 95% CI: 1.00–5.80); conversely, no difference was found between non-trained dental students under supervision and trained dentists (HR 0.52, 95% CI: 0.16–1.70). Additionally, dentin lesions were 59% more-likely-to-present progression than enamel lesions (HR 0.41, 95% CI: 0.17–0.99).

Conclusion

The operator’s experience and training could influence the success of RI on proximal non-cavitated caries lesions and it should be taken into consideration when choosing this treatment modality.

Infiltration and sealing for managing non-cavitated proximal lesions: a systematic review and meta-analysis

Background

Infiltration and sealing are micro-invasive treatments for arresting proximal non-cavitated caries lesions; however, their efficacies under different conditions remain unknown. This systematic review and meta-analysis aimed to evaluate the caries-arresting effectiveness of infiltration and sealing and to further analyse their efficacies across different dentition types and caries risk levels.

Methods

Six electronic databases were searched for published literature, and references were manually searched. Split-mouth randomised controlled trials (RCTs) to compare the effectiveness between infiltration/sealing and non-invasive treatments in proximal lesions were included. The primary outcome was obtained from radiographical readings.

Results

In total, 1033 citations were identified, and 17 RCTs (22 articles) were included. Infiltration and sealing reduced the odds of lesion progression (infiltration vs. non-invasive: OR = 0.21, 95% CI 0.15–0.30; sealing vs. placebo: OR = 0.27, 95% CI 0.18–0.42). For both the primary and permanent dentitions, infiltration and sealing were more effective than non-invasive treatments (primary dentition: OR = 0.30, 95% CI 0.20–0.45; permanent dentition: OR = 0.20, 95% CI 0.14–0.28). The overall effects of infiltration and sealing were significantly different from the control effects based on different caries risk levels (OR = 0.20, 95% CI 0.14–0.28). Except for caries risk at moderate levels (moderate risk: OR = 0.32, 95% CI 0.01–8.27), there were significant differences between micro-invasive and non-invasive treatments (low risk: OR = 0.24, 95% CI 0.08–0.72; low to moderate risk: OR = 0.38, 95% CI 0.18–0.81; moderate to high risk: OR = 0.17, 95% CI 0.10–0.29; and high risk: OR = 0.14, 95% CI 0.07–0.28). Except for caries risk at moderate levels (moderate risk: OR = 0.32, 95% CI 0.01–8.27), infiltration was superior (low risk: OR = 0.24, 95% CI 0.08–0.72; low to moderate risk: OR = 0.38, 95% CI 0.18–0.81; moderate to high risk: OR = 0.20, 95% CI 0.10–0.39; and high risk: OR = 0.14, 95% CI 0.05–0.37).

Conclusion

Infiltration and sealing were more efficacious than non-invasive treatments for halting non-cavitated proximal lesions.

Managing dental caries against the backdrop of COVID-19: approaches to reduce aerosol generation

The COVID-19 pandemic resulted in severe limitation and closure of dental practices in many countries. Outside of the acute (peak) phases of the disease, dentistry has begun to be practised again. However, there is emerging evidence that SARS-CoV-2 can be transmitted via airborne routes, carrying implications for dental procedures that produce aerosol. At the time of writing, additional precautions are required when a procedure considered to generate aerosol is undertaken.This paper aims to present evidence-based treatments that remove or reduce the generation of aerosols during the management of carious lesions. It maps aerosol generating procedures (AGPs), where possible, to alternative non-AGPs or low AGPs. This risk reduction approach overcomes the less favourable outcomes associated with temporary solutions or extraction-only approaches. Even if this risk reduction approach for aerosol generation becomes unnecessary in the future, these procedures are not only suitable but desirable for use as part of general dental care post-COVID-19.

3D imaging of proximal caries in posterior teeth using optical coherence tomography

Optical coherence tomography (OCT) can create cross-sectional images of tooth without X-ray exposure. This study aimed to investigate the diagnostic accuracy of 3D imaging of OCT for proximal caries in posterior teeth. Thirty-six human molar teeth with 51 proximal surfaces visibly 6 intact, 16 slightly demineralized, and 29 distinct carious changes were mounted to take digital radiographs and 3D OCT images. The sensitivity, specificity and area under the receiver operating characteristic curve (AUC) for the diagnosis of enamel caries and dentin caries were calculated to quantify the diagnostic ability of 3D OCT in comparison with digital radiography. Diagnostic accuracy was evaluated by the agreement with histology using weighted Kappa. OCT showed significantly higher sensitivity, AUC and Kappa values than radiography. OCT can be a safer option for the diagnosis of proximal caries in posterior teeth that can be applied to the patients without X-ray exposure.

Anti-caries effect of resin infiltrant modified by quaternary ammonium monomers

OBJECTIVES

Resin infiltrant is used in early enamel caries. However, commercial resin infiltrant lacks persistent antibacterial activity. Dimethylaminododecyl methacrylate (DMADDM) was added to resin infiltrant to give it sustainable antibacterial properties and inhibit demineralization.

METHODS

After the application of resin infiltrant to bovine enamel, cytotoxicity, surface roughness, and aesthetics were assessed. A multi-species biofilm was incubated on the enamel disk before and one month after microbial-aging. After a 48-h anaerobic incubation, biomass accumulation, metabolic activity, and lactic acid were analyzed using a crystal violet assay, an MTT (3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, and a lactic acid assay. Biofilm structure and composition were determined by live/dead staining, exopolysaccharide (EPS) staining, scanning electron microscopy (SEM), and quantitative polymerase chain reaction (qPCR). The depth and content of demineralization were tested by transverse microradiography (TMR).

RESULTS

Incorporating DMADDM did not increase the cytotoxicity or change the physical properties when the mass fraction of the DMADDM was 2.5-10 %. The modification decreased the amount of bacterial biofilm, metabolic activity, lactic acid production, EPS, and the proportion of Streptococcus mutans in the biofilms. It also provided anti-demineralization effects. The surface roughness and antibacterial ability were not changed after one month of microbial-aging.

CONCLUSION

The incorporation of DMADDM improved the antibacterial and anti-demineralization effects of the material. It demonstrated a sustained antibacterial effect.

CLINICAL SIGNIFICANCE

The antibacterial modification might be a potential choice for future clinical applications to inhibit early enamel caries.

How to intervene in the caries process: proximal caries in adolescents and adults-a systematic review and meta-analysis

OBJECTIVES

For an ORCA/EFCD consensus, this systematic review assessed the question "How to intervene in the caries process in proximal caries in adolescents and adults".

MATERIAL AND METHODS

Separating between the management of initial and cavitated proximal caries lesions, Medline via PubMed was searched regarding non-operative/non-invasive, minimally/micro-invasive and restorative treatment. First priority was systematic reviews or randomized controlled trials (RCTs), otherwise cohort studies. After extraction of data, the potential risk of bias was estimated depending on the study type, and the emerging evidence for conclusions was graded.

RESULTS

Regarding non-invasive/non-operative care (NOC), no systematic reviews or RCTs were found. In cohort studies (n = 12) with a low level of evidence, NOC like biofilm management and fluoride was associated with a low proportion and slow speed of progression of initial proximal lesions. Minimally/micro-invasive (MI) treatments such as proximal sealants or resin infiltration (four systematic reviews/meta-analyses) were effective compared with a non-invasive/placebo control at a moderate level of evidence. Data on restorative treatment came with low evidence (5 systematic reviews, 13 RCTs); with the limitation of no direct comparative studies, sample size-weighted mean annual failure rates of class II restorations varied between 1.2 (bulk-fill composite) and 3.8% (ceramic). Based on one RCT, class II composite restorations may show a higher risk of failure compared with amalgam.

CONCLUSIONS

Proximal caries lesions can be managed successfully with non-operative, micro-invasive and restorative treatment according to lesion stage and caries activity.

CLINICAL RELEVANCE

Proximal caries treatment options like non-operative, micro-invasive and restorative care should be considered individually.

Pediatric Dentists' Educational Experiences, Attitudes, and Professional Behavior Concerning Resin Infiltration: Implications for Dental Education

Minimally invasive dentistry (MID) is receiving increased attention. Resin infiltration (RI) is one micro-invasive technique for treating initial caries by sealing white spot lesions on tooth surfaces. The aims of this study were to assess pediatric dentists' RI-related educational experiences, attitudes, and professional behavior and to determine if their educational experiences were significantly related to their professional attitudes and behavior regarding RI. This cross-sectional study used an online survey to collect data from members of the American Academy of Pediatric Dentistry (AAPD) in March-April 2017. Of the 2,367 AAPD members invited to participate, 43 emails could not be delivered, and 273 surveys were completed, for a response rate of 11.8%. While only 9% of the 273 respondents reported that their classroom-based dental education had informed them about RI and only 1% that it had prepared them well to use RI with pediatric patients, higher percentages said they had been informed/prepared well by their classroom-based (24%) and clinical residency education (12%). The majority wanted to learn more about RI (71%) and would like to take a related CE course (59%). The respondents' average RI-related attitudes were positive (on five-point scale with 1=worst attitude: Mean=3.84). Regarding use of RI, 28% of respondents said they used RI sometimes and 4% often/very often, with 64% considering implementing RI in their clinics. Graduation year did not correlate with RI attitudes and use. However, the more education about RI the respondents had received during their residency (r=0.20; p<0.01) and in professional development after graduation (r=0.34; p<0.001), the more they used RI in their own work. This study found that the pediatric dentists' RI-related education was positively correlated with their professional behavior. Increasing predoctoral, resident, and continuing professional education about RI should therefore be considered.

Myristyltrimethylammonium Bromide (MYTAB) as a Cationic Surface Agent to Inhibit Streptococcus mutans Grown over Dental Resins: An In Vitro Study

This in vitro study evaluated the effect of myristyltrimethylammonium bromide (MYTAB) on the physical, chemical, and biological properties of an experimental dental resin. The resin was formulated with dental dimetacrylate monomers and a photoinitiator/co-initiator system. MYTAB was added at 0.5 (G_0.5%), 1 (G_1%), and 2 (G_2%) wt %, and one group remained without MYTAB and was used as the control (G_Ctrl). The resins were analyzed for the polymerization kinetics, degree of conversion, ultimate tensile strength (UTS), antibacterial activity against Streptococcus mutans, and cytotoxicity against human keratinocytes. Changes in the polymerization kinetics profiling were observed, and the degree of conversion ranged from 57.36% (±2.50%) for G_2% to 61.88% (±1.91%) for G_0.5%, without a statistically significant difference among groups (p > 0.05). The UTS values ranged from 32.85 (±6.08) MPa for G_0.5% to 35.12 (±5.74) MPa for G_Ctrl (p > 0.05). MYTAB groups showed antibacterial activity against biofilm formation from 0.5 wt % (p < 0.05) and against planktonic bacteria from 1 wt % (p < 0.05). The higher the MYTAB concentration, the higher the cytotoxic effect, without differences between G_Ctrl e G_0.5% (p > 0.05). In conclusion, the addition of 0.5 wt % of MYTAB did not alter the physical and chemical properties of the dental resin and provided antibacterial activity without cytotoxic effect.

Ex vivo investigation on internal tunnel approach/internal resin infiltration and external nanosilver-modified resin infiltration of proximal caries exceeding into dentin

This ex vivo proof-of-concept study aimed to investigate the effect of nanosilver particles (AgNP) added to a conventional infiltrant resin (Icon) on external penetration into natural proximal enamel caries exceeding into dentin after internal tunnel preparation and internal infiltration. Carious lesions (ICDAS codes 2/3) of extracted human (pre-)molars revealing proximal caries radiographically exceeding into dentin (E2/D1 lesions) were preselected. Then, 48 of those specimens showing demineralized areas transcending the enamel-dentin border as assessed by means of near-infrared light transillumination (DIAGNOcam) were deproteinized (NaOCl, 5%). Using an internal tunnel approach, occlusal cavities central to the marginal ridge were prepared. Excavation of carious dentin, total etch procedure (H3PO4, 40%), and internal resin infiltration (FITC-labeled) followed, along with final restorations (flowable composite resin). Outer lesion surfaces were etched (HCl, 15%) prior to external infiltration (RITC-labeled). Group 1 (control; n = 24) used non-modified infiltrant, while an infiltrant/AgNP mixture (20 nm; 5.5 wt%) was used with experimental Group 2 (n = 24). Non-infiltrated pores of cut lesions were stained (Berberine), and specimens were analyzed using confocal laser scanning microscopy. Compared to the non-filled infiltrant, incorporation of AgNP had no effect on the resin's external penetration. Between the groups, no significant differences regarding internal or external infiltration could be detected, and non-infiltrated lesion areas did not differ significantly (p>0.109; t-test). The internal tunnel preparation in combination with both an internal resin infiltration and an additional external infiltration approach using a nanosilver-modified infiltrant resin leads to increased infiltrated lesion areas, thus occluding and adhesively stabilizing the porous volume of the demineralized enamel. While exerting antimicrobial effects by the nanosilver particles, this approach should have the potential as a viable treatment alternative for proximal lesions extending into dentin, thus avoiding the sacrifice of sound enamel, postponing the frequently inevitable restoration/re-restoration cycle of conventional proximal caries treatment, and improving dental health.

Efficacy of Proximal Resin Infiltration on Caries Inhibition: Results from a 3-Year Randomized Controlled Clinical Trial

This study reports 3-y outcomes of a split-mouth randomized clinical trial. Resin infiltration’s capacity to arrest caries lesion progression in noncavitated proximal lesions is affirmed. Forty-two consented young adults, blinded to tooth surface allocation, were treated with resin infiltration on 1 randomly selected surface and concurrently experienced a mock infiltration procedure on another. Both treatments were provided as an adjunct to the currently accepted standard-of-care regimen (periodic prophylaxis and serial fluoride varnish applications) appropriate for the management of high caries risk. Challenging periods of low oral hygiene compliance were expected. The primary outcome measure was 3-y radiographic lesion progression. Blinded investigators evaluated each study surface for lesion progression with a series of images obtained at intervals over the 3-y course of study. Proportions of progressing lesions were compared with McNemar’s test. Twenty-nine noncavitated lesion pairs in permanent posterior teeth demonstrating caries penetrating into inner enamel or outer dentin were included in the analyses. No adverse events were reported. Radiographic progression was recorded in 4 of 29 infiltrated lesions (14%) and 14 of 29 control lesions (48%, P < .003). Adjunct resin infiltration demonstrated a high 3-y efficacy of 71% (relative risk reduction). The prevented fraction was 86% for infiltration versus 52% for controls. Resin infiltration was 100% successful in arresting caries progression in inner enamel lesions (E2) and 64% in outer dentin lesions (D1). Supplementary microinvasive resin infiltration is significantly more efficacious in reducing proximal lesion progression than management by standard noninvasive therapy alone. Long-term results may shed light on whether this represents the arrest or delay of the caries disease process (ClinicalTrials.gov NCT01584024).