Micro-tensile bond strength and interfacial characterization of an adhesive bonded to dentin prepared by contemporary caries-excavation techniques

The role of etching protocols on bond strength of universal adhesives applied to caries affected dentin: a systematic review and meta-analysis

OBJECTIVES

This systematic review aimed to detect whether acid etching pretreatment would enhance the bond strength of universal adhesives (UAs) to caries-affected dentin before and after aging.

METHODOLOGY

Two independent researchers reviewed materials published until August 2024 in five databases (Web of Science, PubMed, SciELO, Scopus, Science Direct, and Cochrane Library). The eligibility criteria contained in vitro studies that assessed the bond strength of UAs to caries-affected dentin using etch-and-rinse and self-etch modes, with or without aging. Statistical meta-analysis was performed using inverse variance method by the Review Manager program (p < 0.05).

RESULTS

In total, 26 studies were included in the quantitative analysis. Studies have mostly focused on mild UAs. The application of acid etching did not impact the bond strength of ultra-mild and mild UAs (p > 0.05). Aging considerably reduced the bond strength of mild UAs in etch-and-rinse or self-etch modes (p < 0.05). Bond strength to caries-affected dentin was considerably lower than that to sound dentin in both etching modes (p < 0.05).

CONCLUSIONS

Pretreatment with phosphoric acid did not affect the bond strength of mild and ultra-mild UAs to caries-affected dentin. The aging process led to a decrease in the bond strength of mild UAs to caries-affected dentin, irrespective of the application strategy.

A Bibliometric Analysis (2010-2020) of the Dental Scientific Literature on Chemo-Mechanical Methods of Caries Removal Using Carisolv and BRIX3000

Reports in the literature have proposed and analyzed several minimally invasive techniques for caries removal in recent decades. In light of recent events surrounding the ongoing epidemiological context, concerns have been raised regarding the generation of aerosols during dental procedures. The aim of our research was to provide an overview of the scientific literature on the topic of chemo-mechanical caries removal (CMCR) methods, focusing on two products (Carisolv, BRIX3000), commercially available in Europe. A bibliometric analysis was used to investigate the scientific articles included in Web of Science (WoS) Core Collection database, published from January 2010 to December 2020. We analyzed the co-occurrence of all keywords (Author Keywords and the KeyWords Plus section), co-authorship and co-citation, using the free software VOSviewer. Our bibliometric analysis revealed a worldwide interest in the subject of chemo-mechanical methods of caries removal, which has transcended the area of pediatric dentistry. The analyzed studies have been conducted mainly in high-income countries that have developed sanitary policies regarding prevention and early treatment of carious lesions as a health priority.

Biodentine or Mineral Trioxide Aggregate as Direct Pulp Capping Material in Mature Permanent Teeth with Carious Exposure? A Systematic Review and Meta-analysis

OBJECTIVE

To evaluate the success rate of direct pulp capping (DPC) with Biodentine in mature permanent teeth with carious vital pulp exposure compared to that of DPC with mineral trioxide aggregate (MTA) by means of a systematic review and meta-analysis.

DATA SOURCES

The two authors searched independently the literature published through July 31, 2020, in five electronic databases (PubMed, the Cochrane Central Register of Controlled Trials, Web of Science Core Collection, the Wiley Online Library, and the SCOPUS database).

STUDY SELECTION

The research protocol was previously registered in the PROSPERO database (CRD42020192511). Clinical studies that met the inclusion criteria were chosen and independently screened by the authors.

DATA EXTRACTION

A custom-designed spreadsheet was used to extract the data. The quality of each study was evaluated by means of the revised Cochrane risk of bias (ROB) tool or the ROB of nonrandomized studies of interventions tool.

DATA SYNTHESIS

Three randomized controlled trials and one retrospective study met the inclusion criteria. Only one study had a high risk of bias. The included studies reported data on a total of 95 participants with an age range of 8-51 years. No significant difference was observed in the overall treatment outcome when comparing Biodentine with MTA (Risk ratio=1.00, 95% confidence interval [0.93-1.07], p=1.00).

CONCLUSIONS

Biodentine had comparable clinical and radiographic success to that of MTA when used as a DPC agent in mature permanent teeth with carious vital pulp exposure. Additional high-quality studies are needed.

Contemporary restorative ion-releasing materials: current status, interfacial properties and operative approaches

Minimally invasive (MI) concepts in restorative dentistry in the year 2020 request from the practitioner not only a scientifically supported rationale for carious tissue removal/excavation and defect-oriented, biological cavity preparation, but also a deep understanding of how to ensure a biomechanically stable and durable restoration in different clinical situations by applying different restorative options. Bio-interactive materials play an increasingly relevant role, as they not only replace diseased or lost tissue, but also optimise tissue mineral recovery (among other properties) when used in restorative and preventive dentistry. Indeed, this is of certain interest in MI restorative dentistry, especially in those cases where gap formation jeopardises the integrity of the margins along resin composite restorations, causing penetration of bacteria and eventually promoting the formation of secondary caries. Recently, the interest in whether ion-releasing materials may reduce such biofilm penetration into margin gaps and reduce such a risk for development and propagation of secondary caries is growing significantly among clinicians and scientists. The aim of this article was to explore mechanisms involved in the process that allow mineral deposition at the interface between such materials and dentine, and to describe how conventional 'bioactive' restorative materials currently available on the market may benefit treatments in MI dentistry.

Evaluation and Comparison of Caries Excavation Efficacy of Three Different Burs: A Micro-computed Tomographic-assisted Study

Aims and Objectives:

The aim of this study was to evaluate the effectiveness of three different caries excavation methods using micro-computed tomography (micro-CT).

Materials and Methods:

Fifteen freshly extracted human molar teeth with occlusal dentinal caries were selected. The teeth were sectioned longitudinally into two halves and were randomly divided into three groups (n = 10) depending on the caries removal technique: Group 1: tungsten carbide (TC) bur, Group 2: cerabur (CB), and Group 3: Excavus (EX) tipEX). A preoperative micro-CT scan of all the samples was taken. The caries excavation procedures were carried out followed by postoperative micro-CT scan. The preoperative and postoperative scans of each tooth were analyzed for caries removal effectiveness (CRE), mineral density (MD), and minimal invasiveness potential (MIP) using Avizo 9.4 software (Thermo Fisher Scientific, Germany). Statistical analysis was conducted by applying three-way analysis of variance and independent sample t-test using the Statistical Package for the Social Sciences software, version 20.0 (IBM Corporation, USA).

Results:

Among the three groups, the TC group had the smallest RC/IC (residual caries/initial caries) ratio, highest mean MD at the cavity floor, and highest MIP. The EX group significantly had the highest RC/IC, lowest mean MD, and lowest MIP. Both the CRE and MIP parameters of CB group were acceptable (RC/IC = 0.08, mean MD = 1.09g/cm³, and MIP = 1.09).

Conclusion:

As compared with the three excavation methods, CBs can be considered as an alternative to TC burs because of its MIP and complete removal of infected carious dentin.

Bond strength of adhesive systems to sound and demineralized dentin treated with bioactive glass ceramic suspension

OBJECTIVE

The objective of this study was to evaluate the effect of a Biosilicate®, associated with dentin adhesive system, on microtensile bond strength (μTBS) to sound and demineralized dentin.

MATERIALS AND METHODS

Eighty sound-extracted molars had their middle occlusal dentin exposed. In forty teeth, dentin was artificially demineralized (pH cycling). Sound and demineralized dentin teeth were separated into four groups (n = 10), according to the substrate treatment before restoration: Group 1-total-etching adhesive Adper TM Single bond 2 (ASB) + Biosilicate®, Group 2-ASB (without Biosilicate®), Group 3-AdheSE self-etching adhesive system (AdSE) + Biosilicate®, and Group 4-AdSE (without Biosilicate®). Each tooth was restored with a hybrid composite and stored in water at 37 °C for 6 months. After water aging, teeth were cut in sticks (≈ 1 mm² cross-sectional area) and all samples were submitted to μTBS test. The fracture modes of the samples were analyzed by stereomicroscopy. The representatively fractured samples were observed by scanning electron microscopy. Representative samples of each group were analyzed on energy dispersive X-ray spectrometry (EDX). The μTBS and Ca-P ratio values were analyzed by 2-way ANOVA, Bonferroni, and Tukey test, respectively, p < .05.

RESULTS

ASB + Biosilicate® presented the highest μTBS values (p < .05), and lowest μTBS values (p < .05) were found in AdSE Group. There was no statistical difference (p < .05) on μTBS when substrates were compared, except for Group 2. The fracture pattern analysis showed prevalence of adhesive fractures in all groups.

CONCLUSION

Biosilicate® enhanced bond strength of self-etching and etch-and-rinse adhesives to sound and demineralized dentin.

CLINICAL RELEVANCE

Bioactive glass ceramic suspension could be recommended to be used to improve the dentin bond strengths of the total-etching and self-etching adhesives after acid-etching and priming.

Selective removal of carious lesion with Er:YAG laser followed by dentin biomodification with chitosan

The aim of this study was to evaluate the effect of Er:YAG laser for selective removal of carious lesion, followed by biomodification with chitosan gel where the subsurface microhardness, chemical composition, and morphological changes of the residual caries-affected dentin were examined. Artificial dentinal lesions were created by pH-cycling method (14 days) in 104 bovine specimens (5 × 5 mm). Specimens were randomly divided according to the carious removal method: bur (low-speed handpiece) or Er:YAG laser (250 mJ/4 Hz). Specimens were treated with 35% phosphoric acid and were subdivided into two groups according to dentin biomodification: without chitosan (control) and 2.5% chitosan. Forty specimens were restored with an adhesive system and composite resin. Subsurface microhardness tests were performed in sound dentin, caries-affected dentin, residual caries-affected dentin, and after the restoration. The other 64 specimens were subjected to SEM-EDS atomic analysis. Data were statistically analyzed (p < 0.05). After the Er:YAG laser excavation, the microhardness value of residual caries-affected dentin was higher (p < 0.05) than bur-treated dentin. A significant decrease in the amount of Ca, P, and Ca/P ratio was found after the removal of carious lesions with Er:YAG laser (p < 0.05). The biomodification with chitosan did not influence the microhardness and atomic percentage of Ca, P, and Ca/P ratio of residual caries-affected dentin (p > 0.05). SEM analysis showed morphological changes on residual caries-affected dentin (p > 0.05). The selective removal of carious dentin with Er:YAG laser increased microhardness of residual caries-affected dentin, changing its surface morphology and chemical composition. The biomodification with chitosan did not influence the structural and chemical composition of residual caries-affected dentin.

Is It Possible to induce Artificial Caries-affected Dentin using the Same Protocol to Primary and Permanent Teeth?

AIM

This in vitro study compared the mineral loss of natural and artificially-created caries-affected dentin in primary and permanent teeth using the same protocol to induce caries lesions.

MATERIALS AND METHODS

Twenty molars presenting natural occlusal dentin caries lesions (10 primary-PriC and 10 perma-nent-PermC; control group), and 20 sound molars (10 primary -PripH and 10 permanent-PermpH; experimental group), were selected. Occlusal cavities were prepared in teeth of the experimental group that were submitted to pH-cycling for 14 days to simulate caries-affected dentin. All specimens were longitudinally sectioned and prepared in order to obtain Knoop micro-hardness values from 15 to 250 urn depth, starting in bottom of center of natural lesions or cavities. The microhardness (KHN) data were submitted to three-way repeated measures analysis of variance (ANOVA) and Tukey's tests (α = 0.05).

RESULTS

Considering all depths, there was no statistically significant differences (p > 0.05) between the mineral loss of the control (PriC = 30.9 ± 6.4 and PermC = 40.8 ± 8.6) and experimental (PripH = 27.3 ± 11.1 and PermpH = 35.5 ± 14.0) groups, neither between primary and permanent teeth.

CONCLUSION

The mineral loss of the artificially-created caries-affected dentin is similar to that from naturally developed dentin caries lesions.

CLINICAL SIGNIFICANCE

The pH-cycling model may be a suitable method to simulate caries-affected dentin in both permanent and primary teeth.

Biomimetic remineralization of dentin

OBJECTIVES

Remineralization of demineralized dentin is important for improving dentin bonding stability and controlling primary and secondary caries. Nevertheless, conventional dentin remineralization strategy is not suitable for remineralizing completely demineralized dentin within hybrid layers created by etch-and-rinse and moderately aggressive self-etch adhesive systems, or the superficial part of a caries-affected dentin lesion left behind after minimally invasive caries removal. Biomimetic remineralization represents a different approach to this problem by attempting to backfill the demineralized dentin collagen with liquid-like amorphous calcium phosphate nanoprecursor particles that are stabilized by biomimetic analogs of noncollagenous proteins.

METHODS

This paper reviewed the changing concepts in calcium phosphate mineralization of fibrillar collagen, including the recently discovered, non-classical particle-based crystallization concept, formation of polymer-induced liquid-precursors (PILP), experimental collagen models for mineralization, and the need for using phosphate-containing biomimetic analogs for biomimetic mineralization of collagen. Published work on the remineralization of resin-dentin bonds and artificial caries-like lesions by various research groups was then reviewed. Finally, the problems and progress associated with the translation of a scientifically sound concept into a clinically applicable approach are discussed.

RESULTS AND SIGNIFICANCE

The particle-based biomimetic remineralization strategy based on the PILP process demonstrates great potential in remineralizing faulty hybrid layers or caries-like dentin. Based on this concept, research in the development of more clinically feasible dentin remineralization strategy, such as incorporating poly(anionic) acid-stabilized amorphous calcium phosphate nanoprecursor-containing mesoporous silica nanofillers in dentin adhesives, may provide a promising strategy for increasing of the durability of resin-dentin bonding and remineralizing caries-affected dentin.

The use of computer-assisted FACE for minimal-invasive caries excavation

OBJECTIVES

Caries excavation is still a demanding procedure today. In the past years, methods using light-induced fluorescence have proven their ability to detect bacteria remaining in the tooth's hard tissues. However, methods to control the complete removal of infected dentine have not yet been validated. The aim of the present study was to evaluate the degree of dentine removal during caries excavation using a camera- and software-based device as a guide for fluorescence-aided caries excavation (FACE) in comparison to visual-tactile inspection and a dye-staining method.

MATERIALS AND METHODS

One hundred teeth with carious lesions (C3) were randomly allocated to four groups and excavated with the respective method as primary excavation control method. When the first method indicated complete caries excavation, a second method was used to affirm this. Subsequently, dentine samples were taken to determine residual contamination using PCR. After embedding and sectioning the teeth dentine, microhardness was measured perpendicular to the cavity floor.

RESULTS

By using the camera- and software-based device, 94 % of the cavities tested were free of bacterial contamination. All cavities excavated with the dye-staining or visual-tactile control method were free of bacterial contamination but resulted in a significantly higher dentine removal.

CONCLUSION

The camera- and software-assisted caries excavation seems to be an adequate method to remove contaminated dentine without removing affected dentine.

CLINICAL RELEVANCE

Beside its original application to monitor carious, the device is safe, effective, and easy to use for guided caries excavation and is of worth for both everyday practice and undergraduate education.

Digital image analysis method to assess the performance of conventional and self-limiting concepts in dentine caries removal

OBJECTIVE

To assess dentine caries removal effectiveness (CRE) and minimal invasiveness potential (MIP) of carbide and polymer burs.

METHODS

Sectioned carious molars were photographed. Digital images were taken, before and after caries removal, using a Digital Single Lens Reflex camera. The following regions of interest were measured using visual criteria: Residual Infected Dentine (RI), Residual Affected Dentine (RA), Removal Sound Dentine (RA), Prepared Cavity (PC) and Removed Sound Dentine (RS). CRE was determined on basis of: relative residual infected dentine (RI/II), relative residual carious-affected dentine (RA/IA) and total relative residual dentine (RI+RA/II-IA). MIP was determined on basis of: infected dentine cavity size (PC/II), total relative cavity size (PC/II+IA), and corrected relative cavity size (PC-RS/II+IA).

RESULTS

The polymer bur showed the highest preservation of carious-affected dentine after excavation, when the RA/IA ratio was studied. Both kind of burs showed similar values after assessing the RI/II and RI+RA/II-IA ratios. The infected dentine relative cavity size (PC/II) was higher when the carbide bur was used. Both burs attained similar PC/II+IA and PC-RS/II+IA ratios.

CONCLUSIONS

Polymer burs accomplished the concept of minimal-invasive dentistry, showing its self-limiting ability. The minimal-invasiveness potential showed that carbide burs resulted in the worst compromise between effective and selective infected-caries removal.

Permeability evaluation after decay removal in primary teeth with current caries-excavation techniques

AIM

The goal of the study was to evaluate the effect of caries removal by three various methods on the permeability of class II composite resin restorations in primary molar teeth.

MATERIALS AND METHODS

Forty-five recently extracted primary molars were randomly assigned to three groups for three different methods of caries removal; group 1-mechanical, group 2-caries detector dye, and group 3-Carisolv (n = 15). After that, class II cavities in all groups were restored with the adhesive (Opti Bond Solo Plus) that was applied according to the manufacturer's instruction and a posterior composite (Herculite XRV), which was used incrementally. After 24 hours the samples were thermocycled in water for 500 cycles between 5 and 55°C with a dwell time of 30 sec. Permeability was assessed by the fluid filtration method. The data were analyzed using the ANOVA test while study groups were compared with Tukey test for statistically significant differences at a 5% significance level.

RESULTS

The evaluation of tested groups indicated that the highest (0.80) and least (0.37) mean of permeability was observed in group 2 and 3 respectively. Significant difference was revealed among the tested groups (p = 0.045). The comparison of Carisolv and caries detector dye groups indicated a statistically significant difference (p = 0.037). There was not any significant difference between Carisolv or caries dye in the conventional group.

CONCLUSION

Using the chemomechanical and staining methods for caries removal had no more detrimental effect on permeability than the conventional technique. However, caries detection dye for caries removal could be more harmful than chemomechanical method.

CLINICAL SIGNIFICANCE

None of the current caries-excavation techniques could eliminate permeability in class II composite resin restorations. Furthermore, staining methods do not have an adverse effect on sealing ability in comparison to the conventional technique.