Caries-removal effectiveness and minimal-invasiveness potential of caries-excavation techniques: a micro-CT investigation

An in-vitro evaluation of residual dentin retained after using novel enzymatic-based chemomechanical caries removal agents

To assess the biochemical, mechanical and structural characteristics of retained dentin after applying three novel bromelain-contained chemomechanical caries removal (CMCR) formulations in comparison to the conventional excavation methods (hand and rotary) and a commercial papain-contained gel (Brix 3000). Seventy-two extracted permanent molars with natural occlusal carious lesions (score > 4 following the International Caries Detection and Assessment System (ICDAS-II)) were randomly allocated into six groups (n = 12) according to the excavation methods: hand excavation, rotary excavation, Brix 3000, bromelain-contained gel (F1), bromelain-chloramine-T (F2), and bromelain-chlorhexidine gel (F3). The superficial and deeper layers of residual dentin were examined by Raman microspectroscopy and Vickers microhardness, while the surface morphology was assessed by the scanning electron microscope (SEM). A multivariate analysis of variance followed by Tukey's test (p > 0.05) was performed for data analysis. The novel formulations showed an ability to preserve the partially demineralized dentin that showed a reduced phosphate content with a higher organic matrix. This was associated with lower Vickers microhardness values in comparison to sound dentin and rotary excavation. The collagen integration ratio in all methods was close to sound dentin (0.9-1.0) at the deeper dentin layer. The bromelain-chloramine-T gel (F2) produced the smoothest smear-free dentin surface with a higher number of opened dentinal tubules. In contrast, dense smearing covering the remaining dentin was observed in the manual and rotary methods with obstructed dentin tubule orifices. The bromelain-contained formulations can be considered a new minimally invasive approach for selectively removing caries in deep cavitated dentin lesions.

An in vitro assessment of the residual dentin after using three minimally invasive caries removal techniques

To evaluate the efficiency and effectiveness of three minimally invasive (MI) techniques in removing deep dentin carious lesions. Forty extracted carious molars were treated by conventional rotary excavation (control), chemomechanical caries removal agent (Brix 3000), ultrasonic abrasion (WOODPECKER, GUILIN, China); and Er, Cr: YSGG laser ablation (BIOLASE San Clemente, CA, USA). The assessments include; the excavation time, DIAGNOdent pen, Raman spectroscopy, Vickers microhardness, and scanning electron microscope combined with energy dispersive X-ray spectroscopy (SEM-EDX). The rotary method recorded the shortest excavation time (p < 0.001), Brix 3000 gel was the slowest. DIAGNOdent pen values ranged between 14 and 18 in the remaining dentin and laser-ablated surfaces recorded the lowest reading (p < 0.001). The Ca:P ratios of the remaining dentin were close to sound dentin after all excavation methods; however, it was higher in the ultrasonic technique (p < 0.05). The bur-excavated dentin showed higher phosphate and lower matrix contents with higher tissue hardness that was comparable to sound dentin indicating the non-selectiveness of this technique in removing the potentially repairable dentin tissue. In contrast, the MI techniques exhibited lower phosphate and higher organic contents associated with lower microhardness in the deeper dentin layers. This was associated with smooth residual dentin without smearing and patent dentinal tubules. This study supports the efficiency of using MI methods in caries removal as conservative alternatives to rotary excavation, providing a promising strategy for the clinical dental practice.

Volumetric analysis after caries excavation with caries detecting dyes and chemomechanical caries removal agents using 3D scanner-a randomised clinical trial

AIM

This research aimed to use an extra-oral 3D scanner for conducting volumetric analysis after caries excavation using caries-detecting dyes and chemomechanical caries removal agents in individuals with occlusal and proximal carious lesions.

METHODS

Patients with occlusal (A1, A2, A3) and proximal carious lesions (B1, B2, B3) were treated with the conventional rotary technique, caries detecting dyes (CDD) and chemomechanical caries removal (CMCR) method on 90 teeth (n = 45 for each). Group A1, B1: Excavation was performed using diamond points. Group A2, B2: CDD (Sable Seek™ caries indicator, Ultradent) was applied and left for 10 s, and then the cavity was rinsed and dried. For caries removal, diamond points or excavators were used. Group A3 and B3: BRIX3000 papain gel was applied with a micro-brush for 20 s and was activated for 2 min, and then the carious tissue was removed with a sharp spoon excavator. Post-excavation cavity volume analysis was performed using a 3D scanner. The time required and the verbal pain score (VPS) for pain were scored during excavation. Post-restoration evaluation was performed at 1, 3, and 6 months FDI (Federation Dentaire Internationale) criteria.

RESULTS

Comparison of age, time and volume with study groups were made using Independent Sample' t' test and one-way analysis of variance (ANOVA) for two and more than two groups, respectively. Using Cohen's Kappa Statistics, evaluators 1 and 2 agreed on caries removal status aesthetic, functional and biological properties at different follow-ups. The chi-square test revealed that the rotary groups [A1(2.5 ± 0.4 min) B1(4.0 ± 0.4 min)] had significantly less (p = 0.000) mean procedural time than CDD [A2(4.5 ± 0.4 min) B2(5.7 ± 0.4 min)] and CMCR [A3(5.4 ± 0.7 min) B3(6.2 ± 0.6 min)] groups. The CMCR group showed better patient acceptance and less pain during caries excavation than the rotary and CDD groups. CMCR group showed significantly less mean caries excavated volume(p = 0.000). Evaluation of restoration after 1-, 3-, and 6-month intervals was acceptable for all the groups.

CONCLUSION

Brix3000 helps effectively remove denatured teeth with less pain or sensitivity. The time required for caries removal was lowest in the rotary method and highest in the brix3000 group, while the volume of caries removed was the lowest for brix3000 and highest for the rotary group.

Direct pulp capping procedures - Evidence and practice

The aim of direct pulp capping (DPC) is to promote pulp healing and mineralized tissue barrier formation by placing a dental biomaterial directly over the exposed pulp. Successful application of this approach avoids the need for further and more extensive treatment. In order to ensure a complete pulp healing with the placement of restorative materials, a mineralized tissue barrier must form to protect the pulp from microbial invasion. The formation of mineralized tissue barrier can only be induced when there is a significant reduction in pulp inflammation and infection. Consequently, promoting the healing of pulp inflammation may provide a favorable therapeutic opportunity to maintain the sustainability of DPC treatment. Mineralized tissue formation was observed as the favorable reaction of exposed pulp tissue against a variety of dental biomaterials utilized for DPC. This observation reveals an intrinsic capacity of pulp tissue for healing. Therefore, this review focuses on the DPC and its healing procedure as well as the materials used for DPC treatment and their mechanisms of action to promote pulpal healing. In addition, the factors that can affect the healing process of DPC, clinical considerations and future perspective has been described.

Evaluation of the Efficacy of Minimal Invasive Methods Versus Conventional Methods for Caries Removal in Primary Molars

AIM

Evaluating the efficacy of two "minimal invasive methods" of caries removal (Brix 3000/ceramic bur) in comparison with the conventional method in the management of dental caries in primary molars.  Materials and methods: A sum of 60 teeth from children ranging from four to nine years old of both sexes were selected for this study and randomly assigned to three groups: Group I (Brix 3000), Group II (ceramic bur), and Group III (diamond bur), with 20 teeth per group.

RESULTS

Regarding the efficacy of caries removal, the Brix 3000 group had significantly the lowest efficacy, while the ceramic bur and diamond bur groups were significantly the highest without significant differences between the ceramic and diamond groups. Regarding caries removal time, the Brix 3000 group was significantly the highest, while the diamond bur group was significantly the lowest, and the ceramic bur group was intermediate between them. Regarding pain perception, the Brix 3000 and ceramic bur groups were significantly the lowest, with insignificant differences between them, while the diamond bur group was significantly the highest.

CONCLUSION

Ceramic bur is an excellent alternative treatment for caries removal in children in comparison with conventional methods and CMCR. Brix 3000®, despite being less painful in comparison with drilling methods, has lower efficacy and efficiency.

The in-vitro development of novel enzyme-based chemo-mechanical caries removal agents

OBJECTIVES

Bromelain is a potent proteolytic enzyme that has a unique functionality makes it valuable for various therapeutic purposes. This study aimed to develop three novel formulations based on bromelain to be used as chemomechanical caries removal agents.

METHODS

The novel agents were prepared using different concentrations of bromelain (10-40 wt. %), with and without 0.1-0.3 wt. % chloramine T or 0.5-1.5 wt. % chlorhexidine (CHX). Based on the enzymatic activity test, three formulations were selected; 30 % bromelain (F1), 30 % bromelain-0.1 % chloramine (F2) and 30 % bromelain-1.5 % CHX (F3). The assessments included molecular docking, Fourier-transform infrared spectroscopy (FTIR), viscosity and pH measurements. The efficiency of caries removal was assessed by DIAGNOdent pen, measuring the excavation time and number of applications, followed by a morphological evaluation of the remaining dentine using scanning electron microscopy (SEM). The results were compared to Brix 3000 as a control.

RESULTS

The chloramine and chlorhexidine were chemically compatible with bromelain without compromising the enzyme activity. All experimental formulations showed higher viscosity and pH in comparison to Brix 3000. The DIAGNOdent readings were <20 in all groups, and the lowest readings were observed in F2. The excavation time and number of applications were lowest in F2 and F1. Both F2 and F3 produced smooth dentine surfaces with less tissue debris, but more patent dentine tubules were observed in F1 and F2.

CONCLUSIONS

The bromelain-contained formulations showed a potential to be used as chemomechanical caries removal agents in vitro. Further laboratory and clinical studies are needed to validate this claim.

CLINICAL SIGNIFICANCE

The bromelain from pineapple stem has broad specificity for cleavage the peptide bonds in denatured protein to facilitate their removal. The study proved the efficiency of this enzyme to remove the dental caries chemomechanically when used alone or conjugated with chloramine and/or chlorhexidine to enhance the disinfecting and cleansing properties.

Tracing of Microbes in Prepared Cavity Following Different Minimally Invasive Caries Removal Protocols

AIMS

The conventional caries removal technique has been replaced with minimally invasive (MI) techniques to preserve healthy natural teeth and to provide durable dental restorations. Each of these MI caries removal protocols is reported to be favorable in dealing with different caries conditions. The current study aimed to trace the residual bacteria that may remain in a prepared cavity following a visual-tactile (VT), caries detection dye (CDD), and chemo-mechanical caries removal (CMCR) protocol.

MATERIALS AND METHODS

A total of 29 extracted human molar teeth with visible caries lesions were randomly divided into three groups. The cavity preparation and caries removal of each group was accomplished following one of the MI caries removal protocols. Swab samples (one from each specimen) were taken and inoculated onto a blood agar plate and incubated for 48 hours. The growth of the bacterial colony was observed under a microscope and the specific genome of the bacteria was identified by polymerase chain reaction (PCR) test.

RESULTS

The maximum number of traceable bacteria was observed following the chemo-mechanical caries removal group followed by the caries detection dye group and the least in the visual-tactile group. The PCR test revealed the presence of Streptococcus mutans in all the observed colonies; however, Streptococcus sobrinus was absent completely. The Chi-square test reveals a statistically insignificant (p = 0.646) difference among the tested groups.

CONCLUSION

All of the MI caries removal protocols used in this study showed a trace of microbes in certain teeth. The cavity prepared following a visual tactile protocol showed the least amount of traceable bacteria in the prepared cavity.

CLINICAL SIGNIFICANCE

Cavity that is prepared following individual MI protocol has a risk of leaving microbes in it.

Diagnosis and Assessment of Dental Caries Using Novel Bioactive Caries Detecting Dye Solution

BACKGROUND

The goal of materials should be early caries detection, removal of carious lesions, and reduction of dentin hypersensitivity. Thus, the study aims to determine the efficacy of a bioactive caries detecting dye (BCD) for the diagnosing and mechanical removal of occlusal and proximal dental caries.

METHODS

Patients with occlusal (A1, A2) and proximal carious lesions (B1, B2) were treated with the rotary technique and BCD solution on 120 teeth (n = 60 for each). Group 1: Excavation was performed using diamond points. Group 2: 0.5 mL of BCD solution was scrubbed for 20 sec and excavation was performed with a sharp spoon excavator. Post-excavation cavity volume analysis was performed using a 3D scanner. The time required, VAS for pain, VAS for facial expression, and sound eye motor scoring were scored during excavation. Post-restoration evaluation was performed at 3, 6, and 12 months (FDI criteria).

RESULTS

The chi-square test revealed that the A1 (197.90 30.97 s) and B1 (273.06 69.95 s) had significantly less mean procedural time than the A2 (292.13 44.87 s) and B2 (411.86 88.34 s). BCD (A2, B2) group showed good patient acceptance, less pain during caries excavation VAS (p = 0.001, FACE (p = 0.001), and SEM (p < 0.001) analysis than the rotary group. There was a statistically insignificant difference between groups immediately (p = 0.235), (p = 0.475) and after 24 h (p = 0.561), (p = 0.688). Color score, hardness of excavated surface, and caries removal score for occlusal and proximal groups showed insignificant differences between the groups. BCD group showed significantly less mean caries excavated volume for the occlusal group (p = 0.003) as compared to the proximal group (p = 0.417) evaluated by 3D scanner. Evaluation of restoration after 3-, 6-, and 12 months intervals (Occlusal caries group (p = 0.247), (p = 0.330), and (0.489) and Proximal caries group (p = 0.299), (p = 0.594), and (0.494)) was acceptable for both the groups.

CONCLUSION

BCD helps in identification of dental caries clinically, radiographically, and in effective removal of denatured teeth with less pain or sensitivity.

Chemomechanical Caries Removal Methods: A Literature Review

Aim

To provide dental practitioners and researchers with a comprehensive review of the historical development, chemical composition, mechanisms of action, advantages, and drawbacks of different chemomechanical caries removal (CMCR) agents.

Methods

An electronic search was performed for all articles published on CMCR agents in various databases, including the Web of Science, PubMed, Cochrane, Scopus, and Google Scholar bibliographic databases, from January 1, 1975, to July 31, 2022.

Results

Records were identified using the following search terms: Brix3000, Carie-Care, Caridex, Carisolv, chemomechanical caries removal, conventional surgical method, and Papacárie. A total of 171 articles were screened based on the titles and abstracts, of which 126 were deemed eligible for inclusion after duplicates were removed. Following a manual search of the reference list, eight articles were added. Articles were then excluded for other reasons, such as being written before 1975, being written in a language other than English, and the non-availability of the full text. Overall, 120 articles were included in the analysis (literature reviews [n = 27], systematic reviews [n = 8], research articles [n = 82], case reports [n = 3]).

Conclusion

CMCR is a potential method of caries control in the future as an alternative to the conventional surgical approach in standard dentistry applications. It is more widely accepted, less painful, and has comparable efficacy to the conventional surgical method.

Clinical significance

A continuous trend among manufacturers has been observed since 1975 to reduce the drawbacks of CMCR agents. Moreover, evidence-based minimally invasive techniques, including CMCR agents that require minimal or no aerosol-generating procedures, are preferred while measures to control the spread of coronavirus disease are in force.

Evaluation of the Efficacy of Recent Caries Removal Techniques: An In Vitro Study

INTRODUCTION

Dentistry is undergoing a gentle revolution that will consign drill and fill to history. In order to increase the acceptance of dental treatment, efforts are directed toward changing traditional painful dentistry into a new concept of painless dentistry. It is common practice to utilize burs for caries removal and cavity preparation. Chemomechanical caries removal is a painless procedure that uses a chemical substance to eradicate diseased dentine. With the Food and Drug Administration (FDA) approval of Erbium-doped yttrium-aluminum-garnet (Er: YAG) laser systems for caries removal and cavity preparation, the discipline of laser operational dentistry was born out of a desire to find a way to remove the decay without causing any pain or stress to the surrounding healthy tissue.

AIM AND OBJECTIVES

This in vitro research aimed to assess the relative advantages of chemomechanical and laser caries extraction techniques in comparison to the more traditional bur technique. The efficacy of each method was evaluated by microscopic examination of samples treated with each experimental method. We also evaluated the efficiency of each method by recording the time required for caries excavation.

MATERIAL AND METHODS

The methods used for caries excavation were bur excavation, chemo-mechanical method, and laser method. Histological slices were produced after all the samples had been treated with the experimental techniques, and they were studied using a binocular light transmission microscope. The samples were then scored as '0' for absence and '1' for the presence of demineralized dentine. These scores and the time recorded for each method were subjected to statistical analysis.

RESULTS

This study found no statistically significant difference in the effectiveness of the different approaches to removing caries; however, bur excavation was the quickest and chemo-mechanical was the slowest, with the latter not being useful in cases with low caries activity. The laser method of caries removal doesn't remove caries existing in the undercut areas of the cavity thus making the use of bur mandatory.

CONCLUSION

With more practice and experience, the chemo-mechanical and laser methods can be used in a more efficient way to render painless operative procedures to patients.

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.

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.

Commercially Available Ion-Releasing Dental Materials and Cavitated Carious Lesions: Clinical Treatment Options

The contemporary approach for operative caries management emphasizes personalized interventions for each patient, dependent upon the individual's caries susceptibility/risk, the stage of the carious lesion and its activity. The clinician's challenge is to optimize the extent of cavity preparation and the choice of dental restorative biomaterials, appreciating the benefits offered by ion-releasing restorative materials. There is a growing application of bioactive/bio-interactive materials in minimally invasive operative dentistry, as they may help with tissue recovery by ion release. In case of moderate or extensive occlusal cavitation, the clinical criteria include the individual caries susceptibility and carious lesion activity. In high caries risk cases, ion-releasing biomaterials (IRB) can be used, as well as for active carious lesions. In proximal lesions, the clinical criteria include the individual caries susceptibility, the lesion activity and presence of cavities with little or no enamel at the gingival margin. This article aims to discuss the restorative ion-releasing options, according to different clinical situations, and the caries susceptibility to manage cavitated carious lesions in permanent adult teeth.

Polymer-Induced Liquid Precursor (PILP) remineralization of artificial and natural dentin carious lesions evaluated by nanoindentation and microcomputed tomography

OBJECTIVES

The study evaluates the efficacy to remineralize artificial and natural dentin lesions through restorative dental procedures that include the Polymer-Induced Liquid Precursor (PILP) method comprising polyaspartic acid (pAsp).

METHODS

Novel ionomeric cement compositions based on bioglass 45S5 and pAsp mixtures, as well as conditioning solutions (conditioner) containing 5 mg/mL pAsp, were developed and tested on demineralized dentin blocks (3-4 mm thick) on shallow and deep lesions with the thickness of 140 μm ± 50 and 700 μm ± 50, respectively. In the first treatment group, 20 μL of conditioner was applied to demineralized shallow (n = 3) and deep (n = 3) lesion specimens for 20 s before restoration with glass ionomer cement (RMGIC). For the PILP cement treatment group, cement was applied onto the wet surface of the demineralized specimen for both shallow (n = 3) and deep (n = 3) artificial lesions after the application of the conditioner and before the final restoration. Sample groups were compared to RMGIC restoration, for both shallow and deep lesions (n = 3 each) and treatments in PILP-solution (n = 3 for deep lesions) without restoration for 4 weeks. All of the restored specimens were immersed in simulated body fluid (SBF) solution for 2 weeks and 4 weeks for shallow and deep lesions respectively to allow for remineralization. The artificial lesion specimens were evaluated for changes in the nanomechanical profile (E-modulus and hardness) using nanoindentation. Shallow lesions were analyzed by SEM under vacuum for changes in morphology caused by PILP treatments. Also, a pilot study on human third molars with moderate lesions in dentin (n = 3) was initiated to test the efficacy of treatments in natural lesions based on mineral densities using microcomputed tomography (μCT) at 0, 1, and 3 months.

RESULTS

This study showed that functional remineralization of artificial lesions using PILP-releasing restoratives occurred, indicated by an increase of the elastic modulus in shallow lesions and in the middle zone of deep artificial lesions. The mechanical improvement was significant when compared to RMGIC restoration without pAsp (P < 0.05). Nonetheless, recovery across artificial lesions was most significant when specimens were immersed into PILP-solution with restorative (P < 0.01). Furthermore, natural lesions increased in mineral volume content to a higher degree when the restorative treatment included the PILP-method (P < 0.05). However, none of the natural lesions recovered to full mineral degree regardless of the treatments.

CLINICAL SIGNIFICANCE/CONCLUSION

These findings indicate the benefit of PILP applications in the functional repair of dentin caries and illustrate the challenge to integrate the PILP-method into a restorative approach in minimally invasive dental procedures.

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.

Self-Limiting versus Rotary Subjective Carious Tissue Removal: A Randomized Controlled Clinical Trial-2-Year Results

Background: the aim of this study was to assess the 2-year pulp survival of deep carious lesions in teeth excavated using a self-limiting protocol in a single-blind randomized controlled clinical trial. Methods: At baseline, 101 teeth with deep carious lesions in 86 patients were excavated randomly using self-limiting or control protocols. Standardized clinical examination and periapical radiographs of teeth were performed after 1- and 2-year follow-ups (REC 14/LO/0880). Results: During the 2-year period of the study, 24 teeth failed (16 and 8 at T12 and T24, respectively). Final analysis shows that 39/63 (61.9%) of teeth were deemed successful (16/33 (48.4%) and 23/30 (76.6%) in the control and experimental groups, respectively with a statistically significant difference (z score = 2.3, p = 0.021). Of teeth with severe and mild symptoms at T0, 42.9% and 36.7% respectively failed at T24 (p > 0.05). Within the self-limiting group, there was a lower success in premolars compared to molars (p < 0.05). Conclusion: after 2 years, there was a statistically significant higher pulp survival rate of teeth with deep carious lesions excavated using self-limiting protocols in patients with reversible pulpitis. Molars showed higher success than premolars in teeth excavated using the self-limiting protocol. There was no statistically significant association between the outcome and the severity of symptoms at T0 (ClinicalTrials.gov NCT03071588).

Influence of selective caries excavation on marginal penetration of class II composite restorations in vitro

Selective caries excavation may support pulp preservation. This in vitro study investigated the influence of selective removal of demineralized dentin on marginal integrity of composite restorations as determined by dye penetration. Dentinal caries-like lesions were produced in the approximal surfaces of 40 extracted human molars (ethylenediaminetetraacetate, 0.5 M, 96 h). The following test procedures were established: complete excavation, selective excavation, and caries-free control. Two class II cavities with enamel at the cervical margins were prepared per tooth and demineralization volume was determined by micro-computed tomography for the purpose of a stratified distribution to receive complete excavation or selective excavation. After complete or selective excavation (30 cavities each), adhesive composite restorations were placed. Cavities without demineralized dentin (20 cavities) served as control. The marginal integrity of restorations was evaluated by dye penetration with and without thermocycling or mechanical loading. Results were analyzed by non-parametrical statistical tests (Mann-Whitney U Test) with an α = 0.05 level of significance. Dye penetration did not differ significantly among completely excavated, selectively excavated, or undemineralized teeth, but was increased by thermocycling and mechanical loading in all experimental groups. Selective caries removal did not increase marginal penetration in class II restorations. The presence of remaining demineralized dentin surrounded by sound dentin did not impair marginal integrity of restorations with margins placed in sound enamel.

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.

Reactions of Subcutaneous Connective Tissue to Mineral Trioxide Aggregate, Biodentine®, and a Newly Developed BioACTIVE Base/Liner

AIM

There is an increasing interest in the application of BioACTIVE materials to achieve hard tissue formation and maintain pulp vitality. Mineral trioxide aggregate (MTA) and Biodentine® are BioACTIVE materials used for pulp capping. Recently, dental researchers have produced BioACTIVE glass-incorporated light-curable pulp capping material. The study is aimed at evaluating the subcutaneous connective tissue reactions to MTA, Biodentine®, ACTIVA BioACTIVE Base/Liner. These materials were placed in polyethylene tubes and implanted into the dorsal connective tissue of Sprague Dawley rats. The presence of inflammation, predominant cell type, calcification, and thickness of fibrous connective tissue was recorded by histological examination 7, 30, and 60 days after the implantation procedure. Scores were defined as follows: 0 = none or few inflammatory cells, no reaction; 1 = <25 cells, mild reaction; 2 = 25 to 125 cells, moderate reaction; and 3 = ≥125 cells, severe reaction. Fibrous capsule thickness, necrosis, and formation of calcification were recorded. ANOVA and post hoc Dunnett's tests were used for statistically analyses (p < 0.05).

RESULTS

In terms of oedema, inflammation, fibrous capsule, and necrosis, no significant differences were found in any time period for any material. MTA and Biodentine® showed higher calcification than in the ACTIVA BioACTIVE on day 30, and the difference was statistically significant (p < 0.05). After 60 days, while calcification was not seen in the control group, it was observed in the test groups. There was a statistically significant difference between the control and the others.

CONCLUSION

All materials were well tolerated by the tissues in the 60-day evaluation period. One notable finding is the presence of dystrophic calcification in the connective tissue adjacent to the newly developed BioACTIVE Base/Liner material. Therefore, this new BioACTIVE Base/Liner material may be safely recommended to clinicians as a pulp capping material.

Validity of micro-CT for in vitro caries detection: a systematic review and meta-analysis

OBJECTIVE

To investigate the validity of micro-CT for in vitro caries detection in comparison with histology as the reference standard.

METHODS

A systematic search was conducted in the databases Latin American and Caribbean Health Sciences (LILACS), LIVIVO, PubMed, Scopus and Web of Science from their inception to 16 January 2019. Grey literature was searched on Open Grey, ProQuest Dissertations and Theses Database and Google Scholar. In vitro studies assessing the validity of micro-CT for caries detection were included when compared with histology as the reference standard were included. Two authors independently collected the information and sensitivity, specificity, positive and negative likelihood ratios, as well as diagnostic odds ratios were calculated. The risk of bias of the included studies was assessed using the QUADAS-2 tool. Certainty of evidence was assessed with GRADE.

RESULTS

A total of 270 papers were identified, and after a 2-phase selection, 12 studies were included in qualitative and three in quantitative synthesis. For enamel caries diagnostic, sensitivity values ranged from 29.0 to 84.0% indicating high variability while specificity varied from 88.0 to 95.0% indicating good to excellent micro-CT capability do identify the true negative. For dentine caries diagnostic, sensitivity values ranged from 61.0 to 77.0% indicating fair-to-good probability of micro-CT to identify the true positives, while specificity varied from 88.0 to 94.0%. The majority of the included studies presented low risk of bias and moderate certainty of evidence.

CONCLUSIONS

This study demonstrated the validity of micro-CT for in vitro caries detection in comparison with histology.

Histological determination of cariously altered collagen after dentin caries excavation with the polymer bur PolyBur P1 in comparison to a conventional bud bur

BACKGROUND

To compare the polymer bur PolyBur P1 (P1) with tungsten carbide bud bur H1 SE (H1) in removing cariously altered collagen during dentin caries excavation.

METHODS

Fifty extracted teeth were split in the center of a carious lesion. The 100 specimens were randomly divided into 5 groups. Five dentists were asked to excavate 10 teeth each: one half with P1 and the corresponding half with H1. The time needed for caries excavation was measured. Subsequently, histological specimens were produced and analyzed by light-microscope after Mallory-Azan-staining. The thickness of remaining cariously altered collagen was measured (< 1 mm or > 1 mm). The results were statistically evaluated.

RESULTS

The average time to excavate a cavity with P1 was 254 (± 148) sec and 202 (± 129) sec with H1. The difference in times was not statistically significant (p > 0.05). In the group P1 in 66.1% of the sections cariously altered collagen remained, whereas 33.9% showed sound collagen. In the group H1 45.7% sections had remaining cariously altered collagen and 54.3% showed sound collagen. The difference between P1 and H1 was statistically significant (p = 0.004). In the group P1 the layer of cariously altered collagen was significantly more often thicker than 1 mm than in the group H1 (p < 0.05). The variable "type of bur" had a statistically significant influence for the presence of cariously altered collagen (p = 0.003).

CONCLUSIONS

Conventional H1 bud burs were significantly more effective in removing cariously altered collagen during dentin caries excavation than the polymer bur P1.

Fracture resistance of root-filled teeth after cavity preparation with conventional burs, Er: YAG and Er,Cr: YSGG lasers

Purpose

The aim of the present study is to compare the fracture resistance of teeth after access cavity preparation with conventional rotary burs, Erbium-doped yttrium aluminum garnet laser (Er:YAG) and Erbium, cromium: yttrium scandium gallium garnet laser (Er,Cr:YSGG) lasers.

Materials and methods

Fifty five intact mandibular molars were divided into 3 negative groups (groups 1, 2, 3; n=5 for each), 3 study groups (groups 4, 5, 6; n=10 for each) and 1 positive control group (intact teeth; n=10). Access cavities of groups 1, 2 and 3 were prepared with conventional burs, Er:YAG laser and Er,Cr:YSGG laser respectively. After root canal obturation, their coronal portions were left non-restored. Access cavities of groups 4, 5 and 6 were prepared by using the same equipment but their coronal portions were restored with composite resinafter root canal obturation. Following thermocycling, fracture strength was evaluated with a Universal Testing Machine. Mean force at which each sample is fractured was recorded in Newton unit and statistically analyzed.

Results

Fracture resistance of group 7 (intact teeth) was significantly higher than all other groups (p<0.001). Differences among the fracture resistance values of groups 4, 5 and 6 were not significantly different but they were significantly higher than those of groups 1, 2 and 3 (p<0.001). No significant difference was found between Groups 1, 2 and 3.

Conclusion

Preparing access cavities with either laser or bur has no effect on the fracture resistance of teeth with root canal treatment.

Accuracy of visual and image-based ICDAS criteria compared with a micro-CT gold standard for caries detection on occlusal surfaces

The aim of this study was to check the in vitro accuracy of ICDAS criteria on digital images compared to visual examination for the diagnosis of occlusal caries against a micro-CT gold standard. ICDAS was scored in 40 extracted permanent molars by means of visual inspection and stereomicroscopic images. Visual examinations were performed in duplicate and at a one-week interval by three different calibrated examiners. The analysis of digital images by ICDAS criteria was also performed in duplicate, 1 month after visual examinations. The detection methods were compared by means of sensitivity, specificity, area under the curve, predictive positive and negative values, and accuracy for two different thresholds (1- sound vs. carious teeth; 2- tooth requiring operative vs. non-operative treatment). Sensitivity and accuracy values for threshold 1 in the visual ICDAS and image-based ICDAS methods were high for sensitivity (0.93 and 0.97) and for accuracy (0.83 and 0.85), but low for specificity (0.55 for both methods). Specificity values for threshold 2 were 0.77 and 0.82, while sensitivity was 0.33 and 0.28 for each method. Spearman's rank correlation coefficient was 0.53 and 0.43 (p<0.05) for visual and image-based ICDAS compared to the gold standard scores. Both visual and image-based ICDAS scores were similar to each other in terms of diagnostic accuracy when compared to the micro-CT gold standard. Low specificity for the presence of caries and sensitivity for the detection of caries requiring operative treatment were found.

Effectiveness of the Multilayered Caries Model and Visuo-tactile Virtual Reality Simulator for Minimally Invasive Caries Removal: A Randomized Controlled Trial

This work presents the multilayered caries model with a visuo-tactile virtual reality simulator and a randomized controlled trial protocol to determine the effectiveness of the simulator in training for minimally invasive caries removal. A three-dimensional, multilayered caries model was reconstructed from 10 micro-computed tomography (CT) images of deeply carious extracted human teeth before and after caries removal. The full grey scale 0-255 yielded a median grey scale value of 0-9, 10-18, 19-25, 26-52, and 53-80 regarding dental pulp, infected carious dentin, affected carious dentin, normal dentin, and normal enamel, respectively. The simulator was connected to two haptic devices for a handpiece and mouth mirror. The visuo-tactile feedback during the operation varied depending on the grey scale. Sixth-year dental students underwent a pretraining assessment of caries removal on extracted teeth. The students were then randomly assigned to train on either the simulator (n=16) or conventional extracted teeth (n=16) for 3 days, after which the assessment was repeated. The posttraining performance of caries removal improved compared with pretraining in both groups (Wilcoxon, p&lt;0.05). The equivalence test for proportional differences (two 1-sided t-tests) with a 0.2 margin confirmed that the participants in both groups had identical posttraining performance scores (95% CI=0.92, 1; p=0.00). In conclusion, training on the micro-CT multilayered caries model with the visuo-tactile virtual reality simulator and conventional extracted tooth had equivalent effects on improving performance of minimally invasive caries removal.

X-ray microtomography assessment of Carisolv and Papacarie effect on dentin mineral density and amount of removed tissue

OBJECTIVE

The aim of the present study was to directly compare Carisolv and Papacarie regarding the volume of removed tissue (RT) and dentin mineral density (DMD) after excavation.

MATERIALS AND METHODS

Twenty permanent molars were randomized into two groups where caries was excavated using Carisolv or Papacarie followed by removal of softened tissue by a blunt instrument. X-ray microtomography was used to scan teeth before and after excavation generating two- and three-dimensional images that were used to calculate the percentage of RT relative to baseline tooth tissue volume and DMD that was categorized into sound dentin (>1.11 g/cm³) and residual caries (≤1.11 g/cm³). The two groups were compared using t-test Fisher exact test.

RESULTS

DMD was higher after Papacarie than Carisolv (mean = 1.70 and 1.14, p = .14) with higher percentage of cases with sound dentin (70 and 60%, p = 1.00). The percentage of RT was lower after Papacarie than Carisolv (7.40 and 8.95%, p = .31) with 22.95% less RT in cases that ended with sound dentin after excavation.

CONCLUSIONS

There was higher DMD, more sound dentin and less RT when Papacarie was used compared to Carisolv.

Evaluation of dental explorer and visual inspection for the detection of residual caries among Greek dentists

Objectives

The objective of this study was to assess the effect of the operator's degree of clinical experience on the residual caries diagnosis through visual inspection and tactile sensation.

Materials and Methods

The participants were asked about the years of their clinical practice, any further training concerning cariology, their familiarity with the minimal invasive philosophy, and the techniques that they use to remove dental caries and detect when to stop the removal of carious tissues. In addition, an in vitro diagnostic test was conducted. Carious teeth were excavated to a level selected in random. Teeth were examined by each participant individually. Initial examination was performed by visual inspection. Subsequently, a dental explorer was used concerning the potential need for further removal of dental tissues. A sample of 380 dentists and dental school students were selected for the purposes of this study.

Results

Dental students presented statistically significant better sensitivity, than dentists from both age groups, during both visual inspection and tactile sensation of residual caries. Participants' ability to diagnose residual caries during cavity preparation was independent of their years of experience.

Conclusions

During the removal of carious lesions, with the goal of limiting the sacrifice of healthy structures and the leftover of residual caries, clinicians should combine a selective removal technique and the attentive visual inspection, with at least one further diagnostic method, aside from the dental explorer. Tactile examination of residual caries solely with the dental explorer must be used with attention.

A dual energy micro-CT methodology for visualization and quantification of biofilm formation and dentin demineralization

OBJECTIVE

The aim of this study was to induce artificial caries in human sound dentin by means of a microcosm model using human saliva as source of bacteria and to apply a novel dual-energy micro-CT technique to quantify biofilm formation and evaluate its demineralization potential.

DESIGN

Eight sound third molars had the occlusal enamel removed by cutting with a diamond disk and five cylindrical cavities (±2mm diameter; ±1.5mm depth) were prepared over the dentin surface in each specimen (n=40 cavities). After sterilization, each specimen received the bacterial salivary inoculum obtained from individuals without any systemic diseases presenting dentin caries lesions and were incubated in BHI added of with 5% sucrose for 96h to allow biofilm formation. After that, two consecutive micro-CT scans were acquired from each specimen (40kv and 70kv). Reconstruction of the images was performed using standardized parameters. After alignment, registration, filtering and image calculations, a final stack of images containing the biofilm volume was obtained from each prepared cavity. Dentin demineralization degree was quantified by comparison with sound dentin areas. All data were analyzed using Shapiro-Wilk test and Spearman correlation using α=5%.

RESULTS

Dual-energy micro-CT technique disclosed biofilm formation in all cavities. Biofilm volume inside each cavity varied from 0.30 to 1.57mm³. A positive correlation between cavity volume and volume of formed biofilm was obtained (0.77, p<0.01). The mineral decrease obtained in dentin was high (±90%) for all cavities and all demineralized areas showed mineral density values lower than a defined threshold for dentin caries (1.2g/cm³).

CONCLUSION

Dual-energy micro-CT technique was successful in the quantification of a microcosm human bacterial biofilm formation and to quantify its demineralization potential in vitro.

Microhybrid versus nanofill composite in combination with a three step etch and rinse adhesive in occlusal cavities: five year results

Objectives

The aim of the study was to evaluate the 5-year clinical performance of occlusal carious restorations using nanofill and microhybrid composites, in combination with 3-step etch-and-rinse adhesives, in patients who were going to commence orthodontic treatment.

Materials and Methods

A total of 118 restorations for occlusal caries were conducted prior to orthodontic treatment. Occlusal restorations were performed both with Filtek Supreme XT (3M ESPE) and Filtek Z250 (3M ESPE) before beginning orthodontic treatment with fixed orthodontic bands. Restorations were clinically evaluated at baseline and at 1, 2, 3, 4, and 5-year recalls.

Results

None of the microhybrid (Filtek Z250) and nanofill (Filtek Supreme XT) composite restorations was clinically unacceptable with respect to color match, marginal discoloration, wear or loss of anatomical form, recurrent caries, marginal adaptation, or surface texture. A 100% success rate was recorded for both composite materials. There were no statistically significant differences in any of the clinical evaluation criteria between Filtek Z250 and Filtek Supreme XT restorations for each evaluation period.

Conclusions

The composite restorations showed promising clinical results relating to color matching, marginal discoloration, wear or loss of anatomical form, recurrent caries, marginal adaptation, and surface texture at the end of the 5-year evaluation period.

Evidence provided for the use of oscillating instruments in restorative dentistry: A systematic review

Oscillating diamond instruments are considered gentle sources for the removal of demineralized tooth hard tissues and the preparation of cavity angles and margins needed in minimally invasive dentistry. However, there is a question if literature provides enough evidence for their efficacy in restorative dentistry procedures. A literature search until May 2016 was conducted, using PubMed, Scopus, and The Cochrane Central Register of Controlled Trials databases. The quality of the studies was assessed using the recommendation of the Oxford Centre for Evidence-based Medicine. Fifty-five studies were finally included in the study. Of which, 78.2% of them were laboratory studies and only 21.8% were clinical studies. The strength of recommendation was 5 for most of them and D their grade of evidence. Bond strength of adhesives on surfaces prepared with these instruments, effective caries removal and cutting characteristics of the oscillating instruments were the main targets of the studies. Conventional diamond, steel, and chemical vapor deposition diamond tips and systems based on abrasive slurry were the oscillating tips, used in different studies. The strength of recommendation and grade of evidence of the studies were low. Although these devices seem to be useful for many clinical situations, there is a need for more well-structured evidence-based studies with more widely accepted procedures and common devices, to have more meaningful results and conclusions of higher strength.

Comparison of two different methods of detecting residual caries

Objectives

The aim of this study was to investigate the ability of the fluorescence-aided caries excavation (FACE) device to detect residual caries by comparing conventional methods in vivo.

Materials and Methods

A total of 301 females and 202 males with carious teeth participated in this study. The cavity preparations were done by grade 4 (Group 1, 154 teeth), grade 5 (Group 2, 176 teeth), and postgraduate (Group 3, 173 teeth) students. After caries excavation using a handpiece and hand instruments, the presence of residual caries was evaluated by 2 investigators who were previously calibrated for visual-tactile assessment with and without magnifying glasses and trained in the use of a FACE device. The tooth number, cavity type, and presence or absence of residual caries were recorded. The data were analyzed using the Chi-square test, the Fisher's Exact test, or the McNemar test as appropriate. Kappa statistics was used for calibration. In all tests, the level of significance was set at p = 0.05.

Results

Almost half of the cavities prepared were Class II (Class I, 20.9%; Class II, 48.9%; Class III, 20.1%; Class IV, 3.4%; Class V, 6.8%). Higher numbers of cavities left with caries were observed in Groups 1 and 2 than in Group 3 for all examination methods. Significant differences were found between visual inspection with or without magnifying glasses and inspection with a FACE device for all groups (p < 0.001). More residual caries were detected through inspection with a FACE device (46.5%) than through either visual inspection (31.8%) or inspection with a magnifying glass (37.6%).

Conclusions

Within the limitations of this study, the FACE device may be an effective method for the detection of residual caries.

Application of Laser Irradiation for Restorative Treatments

Nowadays, lasers are widely used in many fields of medicine. Also, they can be applied at many branches of dental practice such as diagnosis, preventive procedures, restorative treatments, and endodontic therapies. Procedures like caries removal, re-mineralization, and vital pulp therapy are the most noticeable effects of laser irradiation which has gained much attention among clinicians. With controlled and appropriate wavelength, they can help stimulating dentinogenesis, controlling pulpal hemorrhage, sterilization, healing of collagenic proteins, formation of a fibrous matrix, and inducing hard tissue barrier. Nevertheless, there are many controversies in literatures regarding their effects on the quality of bonded restorations. It hampered a wide application of lasers in some aspects of restorative dentistry and requirements to identify the best way to use this technology. The aim of this mini review is to explain special characteristics of laser therapy and to introduce the possible applications of laser devices for dental purposes.

Microindentation hardness and calcium/phosphorus ratio of dentin following excavation of dental caries lesions with different techniques

BACKGROUND

The aim of this in vitro study was to evaluate the microindentation hardness and chemical composition of residual dentin left at the cavity bottom following removal of carious dentin using the Carisolv chemomechanical and Er:YAG laser caries excavation methods in comparison with the conventional tungsten-carbide bur excavation.

METHODS

Sixty-nine extracted permanent teeth with occlusal dentin caries were assigned into three groups according to caries removal technique. Carious dentin excavation was guided by tactile method and a caries-staining dye. In stereomicroscope images (100×) of the samples, the presence or absence of residual caries was defined. The Knoop hardness value of the cavity floor was determined and atomic analysis of treated cavities was performed by energy dispersive X-ray spectroscopy.

RESULTS

The Knoop hardness value of residual dentin left at the cavity bottom was lower (One-way ANOVA, Dunnett-C, p < 0.05) and the percentage of samples with remaining carious dentin was higher after Carisolv excavation than those obtained after conventional and laser excavations (Kruskal-Wallis, Mann-Whitney U, p < 0.05). No significant differences were found between the quantities of calcium content (Ca wt%), phosphorus content (P wt%) and calcium/phosphorus ratio of the cavities treated by three techniques (Kruskal-Wallis, Mann-Whitney U, p > 0.05).

CONCLUSION

The results indicated that Er:YAG laser was more comparable to conventional bur excavation than chemomechanical method in the efficacy of caries removal with regard to microindentation hardness of remaining dentin and both Carisolv gel and Er:YAG laser did not alter chemical composition of residual dentin in the treated cavities.

Lasers for caries removal in deciduous and permanent teeth

BACKGROUND

Despite considerable improvements in oral health, dental caries continue to be a public health issue. The most frequently used, and universally accepted technique, to remove caries is through mechanical ablation of decayed tissues by means of rotating drills (diamond or tungsten carbide, or both). In the past few decades, the introduction of adhesive filling materials (resin composites) has affected cavity filling procedures by reducing its retention needs, with advantages for dental tissue conservation. Consequently, new minimally invasive strategies were introduced into dental practice, such as the use of lasers to perform highly controlled tissue ablation. Laser use has also raised expectations of limiting pain and discomfort compared to using drills, as well as overcoming drill phobia.

OBJECTIVES

The main objective of the review was to compare the effects of laser-based methods to conventional mechanical methods for removing dental caries in deciduous and permanent teeth.

SEARCH METHODS

We searched the following electronic databases: Cochrane Oral Health's Trials Register (searched 22 June 2016), Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 5) in the Cochrane Library (searched 22 June 2016), MEDLINE Ovid (1946 to 22 June 2016), Embase Ovid (1980 to 22 June 2016), ProQuest Dissertations and Theses (1980 to 22 June 2016), Zetoc (limited to conference proceedings) (1993 to 22 June 2016), and ISI Web of Knowledge (limited to conference proceedings) (1990 to 22 June 2016). We checked the reference lists of relevant articles to identify additional studies. We searched the US National Institutes of Health Ongoing Trials Register ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform for ongoing trials.

SELECTION CRITERIA

We included randomised controlled trials, split-mouth trials and cluster-randomised trials (irrespective of their language) comparing laser therapy to drill ablation of caries. We included participants of any age (children, adolescents and adults).

DATA COLLECTION AND ANALYSIS

Two review authors independently screened titles and abstracts of citations identified by the review search strategy. Two review authors independently evaluated the full text of relevant primary studies, assessed risk of bias and extracted data. We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included nine randomised trials, published between 1998 and 2014, involving 662 participants. The population consisted of both children and adolescents in four trials, only adults in four trials, and both children/adolescents and adults in one trial. Four studies examined only permanent teeth, and five studies evaluated both deciduous and permanent teeth. Six trials used Er:YAG (erbium-doped yttrium aluminium garnet) lasers, two trials employed Er,Cr:YSGG (erbium, chromium: yttrium-scandium-gallium-garnet) lasers, and one trial used Nd:YAG (neodymium-doped yttrium aluminium garnet) laser.Overall, the trials had small sample sizes, and the majority were at unclear or high risk of bias. The primary outcomes were evaluated in a limited number of trials (removal of caries (four trials (but only two reported quantitative data)); episodes of pain (five studies)). There was insufficient evidence to suggest that either lasers or drill were better at caries removal (risk ratio (RR) 1.00, 95% confidence interval (CI) 0.99 to 1.01; 2 studies; 256 treated caries; P = 0.75; I² = 0%; low-quality evidence).The incidence of moderate or high pain was greater in the drill group compared to the laser group (RR 0.40, 95% CI 0.28 to 0.57; 2 studies; 143 participants; P < 0.001; I² = 50%). Similarly, the need for anaesthesia was significantly higher in the drill group than in the laser group (RR 0.25, 95% CI 0.10 to 0.65; 3 studies; 217 children/adolescents; P = 0.004; I² = 0%).In terms of marginal integrity of restoration, there was no evidence of a difference between laser and drill comparisons evaluated at 6 months (RR 1.00, 95% CI 0.21 to 4.78; 3 studies), 1 year (RR 1.59, 95% CI 0.34 to 7.38; 2 studies), or 2 years (RR 1.00, 95% CI 0.21 to 4.74; 1 study).There was no evidence of a difference for durability of restoration between laser therapy or drill at 6 months' follow-up (RR 2.40, 95% CI 0.65 to 8.77; 4 studies), at 1 year (RR 1.40, 95% CI 0.29 to 6.78; 2 studies) or at 2 years' follow-up (RR 0.50, 95% CI 0.02 to 14.60; 1 study).Only two trials investigated the recurrence of caries, but no events occurred during 6 months' follow-up.There was insufficient evidence of a difference between laser or drill in terms of pulpal inflammation or necrosis at 1 week (RR 1.51, 95% CI 0.26 to 8.75; 3 studies) and at 6 months (RR 0.99, 95% CI 0.10 to 9.41; 2 studies).

AUTHORS' CONCLUSIONS

Given the low quality of the body of evidence, we concluded that evidence was insufficient to support the use of laser as an alternative to traditional drill therapy for caries removal. We found some evidence in favour of laser therapy for pain control, need of anaesthesia and patient discomfort, but, again, the body of evidence was of low quality. Additional well-designed, randomised trials investigating the most relevant outcomes are needed.

Managing Carious Lesions

The International Caries Consensus Collaboration undertook a consensus process and here presents clinical recommendations for carious tissue removal and managing cavitated carious lesions, including restoration, based on texture of demineralized dentine. Dentists should manage the disease dental caries and control activity of existing cavitated lesions to preserve hard tissues and retain teeth long-term. Entering the restorative cycle should be avoided as far as possible. Controlling the disease in cavitated carious lesions should be attempted using methods which are aimed at biofilm removal or control first. Only when cavitated carious lesions either are noncleansable or can no longer be sealed are restorative interventions indicated. When a restoration is indicated, the priorities are as follows: preserving healthy and remineralizable tissue, achieving a restorative seal, maintaining pulpal health, and maximizing restoration success. Carious tissue is removed purely to create conditions for long-lasting restorations. Bacterially contaminated or demineralized tissues close to the pulp do not need to be removed. In deeper lesions in teeth with sensible (vital) pulps, preserving pulpal health should be prioritized, while in shallow or moderately deep lesions, restoration longevity becomes more important. For teeth with shallow or moderately deep cavitated lesions, carious tissue removal is performed according to selective removal to firm dentine. In deep cavitated lesions in primary or permanent teeth, selective removal to soft dentine should be performed, although in permanent teeth, stepwise removal is an option. The evidence and, therefore, these recommendations support less invasive carious lesion management, delaying entry to, and slowing down, the restorative cycle by preserving tooth tissue and retaining teeth long-term.

Comparative clinical evaluation of the efficacy of a new method for caries diagnosis and excavation

Aim:

The purpose of this study is to compare the efficiency of fluorescence-aided caries excavation (FACE) to remove carious dentin primary teeth with that of conventional methods.

Methods and Materials:

After caries excavation was carried out, dentin surfaces were conventionally inspected using visual tactile criteria and 415 cavities which were classified as caries-free, re-inspected with Face-Light and caries detector dye (CDD) methods. Orange-red fluorescing areas classified as carious dentin, as well as stained carious dentin. All the data were recorded according to localization of the caries and determination efficiency of the methods. X² test was used to compare the mean values of both Face-Light and dye applications, while Wilcoxon test performed to evaluate the effectiveness for each diagnostic method.

Results:

A total of 273 patients with 415 Class II (OM/OD) cavities (1.65 ± 0.52 teeth per patient) with carious lesions in molar and premolar teeth, were examined. Out of 415 teeth, in 149 teeth (35.9%) no caries findings had been illustrated. While FACE detected remaining carious or partially removed areas in 237 teeth (57.2%), CDD stained only 29 teeth by itself (P < 0.05).

Conclusion:

In conclusion, FACE has a higher detectability compared to visual inspection and caries detector dye in diagnosis and removal of carious dentin.

Caries-removal effectiveness of a papain-based chemo-mechanical agent: A quantitative micro-CT study

The aim of this study was to access the effectiveness and specificity of a papain-based chemo-mechanical caries-removal agent in providing minimum residual caries after cavity preparation. In order to do it, extracted carious molars were selected and scanned in a micro-CT before and after caries-removal procedures with the papain-based gel. Similar parameters for acquisition and reconstruction of the image stacks were used between the scans. After classification of the dentin substrate based on mineral density intervals and establishment of a carious tissue threshold, volumetric parameters related to effectiveness (mineral density of removed dentin volume and residual dentin tissue) and specificity (relation between carious dentin in removed volume and initial caries) of this caries-removal agent were obtained. In general, removed dentin volume was similar or higher than the initial carious volume, indicating that the method was able to effectively remove dentin tissue. Samples with an almost perfect accuracy in carious dentin removal also showed an increased removal of caries-affected tissue. On the contrary, less or no affected dentin was removed in samples where some carious tissue was left in residual dentin. Mineral density values in residual dentin were always higher or similar to the threshold for mineral density values in carious dentin. In conclusion, the papain-based gel was effective in removing carious dentin up to a conservative in vitro threshold. Lesion characteristics, such as activity and morphology of enamel lesion, may also influence caries-removal properties of the method.

Effectiveness of Different Mechanical Methods on Dentin Caries Removal: Micro-CT and Digital Image Evaluation

PURPOSE

To determine the caries removal effectiveness (CRE) and minimal invasive potential (MIP) of caries excavation methods using digital imaging and microtomography analyses.

METHODS

Twelve human molars with occlusal caries lesions in dentin were randomly divided into three groups (carbide bur, exacavator, and polymer bur). They were sectioned mesiodistally, and standardized digital and computed microtomography x-ray (micro-CT) images were taken from each section before and after caries excavation. On each image, initial carious dentin (IC), prepared cavity (PC), and residual caries (RC) were defined according to visual criteria using ImageJ software. CRE was determined based on the RC/IC ratio, whereas MIP was determined by the PC/IC ratio. Data were analyzed using one-way analysis of variance and Student t-test or with Kruskal-Wallis and Student-Newman-Keuls test. The level of significance was set at 0.05.

RESULTS

For both digital image and micro-CT analysis, the carbide bur showed higher CRE values than the excavator (p=0.0063 and p=0.0263, respectively) and the polymer bur (p=0.0028 and p=0.0005, respectively). The latter two presented similar results (p>0.05). Regarding MIP, for the digital image analysis, the polymer bur was different from the carbide bur (p=0.0030) but was not different from that of the excavator (p=0.1240). For micro-CT analysis, the MIP values of all the groups were significantly different, and the polymer bur was the most conservative method (p<0.05).

CONCLUSIONS

The carbide bur was the most effective method for caries removal but was not completely conservative. The polymer bur and excavator presented low invasive potential but were not able to remove all of the carious dentin.

Current update of chemomechanical caries removal methods

Chemomechanical caries removal is an excellent method for minimally invasive caries excavation, and the removal agents are either sodium hypochlorite (NaOCl)- or enzyme-based. The NaOCl-based agents include GK-101, GK-101E (Caridex) and Carisolv, and the enzyme-based agents include Papacarie and the experimental material, Biosolv. This review outlines the changes in chemomechanical caries removal methods and focuses on recently published laboratory and clinical studies. The historical development, mechanism of action, excavation time and biological effects on pulp and dental hard tissues are described. Based on existing evidence, the currently available chemomechanical caries removal methods are viable alternatives to conventional rotary instrument methods. Chemomechanical methods could be extremely useful in very anxious, disabled and paediatric patients. It does seem some of these agents would still benefit from quicker excavation times in order to achieve more universal acceptance. However, as a means of conserving the caries-affected dentine, chemomechanical caries removal is possibly much more successful than conventional rotary instrumentation.

Ablation of carious dental tissue using an ultrashort pulsed laser (USPL) system

The aim of the study was to investigate the efficiency of caries removal employing an ultrashort pulsed laser (USPL) and to compare the results regarding to the ablation rate of sound enamel and dentin including surface texture. The study was performed with 59 freshly extracted carious human teeth. Two cavities with an edge length of 1 × 1 mm per tooth were created: one in the dental decay and one in sound hard tissue. For this purpose a 9-W Nd:YVO4 laser with a center wavelength of 1,064 nm and a pulse duration of 8 ps at a repetition rate of 500 kHz was used. A scanner system moved the laser beam across the surface with a scan speed of 2,000 mm/s. Ablated volume and roughness R z of the cavity ground were measured using an optical profilometer. Subsequently, the specimens were cut to undecalcified sections for histological investigations. The removal of dental decay (dentin, 14.9 mm(3)/min; enamel, 12.8 mm(3)/min) was significantly higher (p < 0.05) compared to the removal of sound tissues (dentin, 4.2 mm(3)/min; enamel, 3.8 mm(3)/min). The arithmetic means of the surface roughness R z were 8.5 μm in carious enamel, 15.43 μm in carious dentin, 4.83 μm in sound enamel and 5.52 μm in sound dentin. Light microscopic investigations did not indicate any side effects in the surrounding tissues. Regarding the ablation rate of dental decay using the USPL system, caries removal seems to be much more efficient for cavity preparation.

Use of new minimum intervention dentistry technologies in caries management

Preservation of natural tooth structure requires early detection of the carious lesion and is associated with comprehensive patient dental care. Processes aiming to detect carious lesions in the initial stage with optimum efficiency employ a variety of technologies such as magnifying loupes, transillumination, light and laser fluorescence (QLF® and DIAGNOdent® ) and autofluorescence (Soprolife® and VistaCam®), electric current/impedance (CarieScan(®) ), tomographic imaging and image processing. Most fluorescent caries detection tools can discriminate between healthy and carious dental tissue, demonstrating different levels of sensitivity and specificity. Based on the fluorescence principle, an LED camera (Soprolife® ) was developed (Sopro-Acteon, La Ciotat, France) which combined magnification, fluorescence, picture acquisition and an innovative therapeutic concept called light-induced fluorescence evaluator for diagnosis and treatment (LIFEDT). This article is rounded off by a Soprolife® illustration about minimally or even non-invasive dental techniques, distinguishing those that preserve or reinforce the enamel and enamel-dentine structures without any preparation (MIT1- minimally invasive therapy 1) from those that require minimum preparation of the dental tissues (MIT2 - minimally invasive therapy 2) using several clinical cases as examples. MIT1 encompasses all the dental techniques aimed at disinfection, remineralizing, reversing and sealing the caries process and MIT2 involves a series of specific tools, including microburs, air abrasion devices, sonic and ultrasonic inserts and photo-activated disinfection to achieve minimal preparation of the tooth. With respect to minimally invasive treatment and prevention, the use of lasers is discussed. Furthermore, while most practices operate under a surgical model, Caries Management by Risk Assessment (CaMBRA) encourages a medical model of disease prevention and management to control the manifestation of the disease, or keep the oral environment in a state of balance between pathological and preventive factors. Early detection and diagnosis and prediction of lesion activity are of great interest and may change traditional operative procedures substantially. Fluorescence tools with high levels of magnification and observational capacity should guide clinicians towards a more preventive and minimally invasive treatment strategy.

Micro-computerized tomography assessment of fluorescence aided caries excavation (FACE) technology: comparison with three other caries removal techniques

BACKGROUND

The aim of this study was to determine the caries removal effectiveness (CRE) and minimal invasiveness potential (MIP) of four dentine caries removal methods.

METHODS

After carious molars were scanned using micro-computerized tomography (micro-CT), dentine caries were removed by fluorescence aided caries excavation (FACE) technology, laser induced fluorescence (LIF), chemomechanical excavation (CME), and conventional excavation (CE). Micro-CT was then repeated. CRE was determined based on the volume of residual caries/initial caries (RC/IC) and the mean mineral density (MD) at the cavity floor. MIP was determined by measuring the volume of the prepared cavity/initial cavity (PC/IC).

RESULTS

Among the four groups, the LIF group had the smallest RC/IC (0.08), the highest mean MD at the cavity floor (1.32 g/cm(3) ) and the highest MIP (4.47). The CME group had the highest RC/IC (0.24), the lowest mean MD (1.01 g/cm(3) ) and the lowest MIP (2.23). The CE group exhibited a more acceptable CRE (RC/IC = 0.13, mean MD = 1.21 g/cm(3) ) but had a higher MIP (3.95). Both the CRE and MIP parameters of FACE technology were the second most acceptable (RC/IC = 0.12, mean MD = 1.13 g/cm(3) , MIP = 3.20) and did not differ significantly from the most acceptable.

CONCLUSIONS

FACE is an effective caries removal technology for removing infected dentine without significantly increasing cavity size.

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.