How does the pulpal response to Biodentine and ProRoot mineral trioxide aggregate compare in the laboratory and clinic?

Histological response of inflamed pulp to hydraulic calcium silicate cements in direct pulp capping: Systematic review of pulpitis models

This systematic review aimed to compare the histological response of inflamed pulpodentinal complex to the hydraulic calcium silicate cements in experimental animal models of pulpitis. Articles that evaluated the histological response of inflamed pulp to mineral trioxide aggregate (MTA) in comparison with other restorative materials were selected and analysed in detail. The risk of bias assessment was conducted using SYRCLE's RoB tool. The GRADEpro tool was used to determine the overall quality of evidence. Out of the 2947 retrieved articles from databases, five articles fulfilled the inclusion criteria. MTA induced significantly more hard tissue formation compared to calcium hydroxide. The use of pulp-capping material containing fluocinolone acetonide and ASP/PLGA-ASP/ACP/PLLA-PLGA composite membrane was comparable. This systematic review could not demonstrate enhanced efficiency of capping materials compared to MTA. Future well-conducted animal studies are warranted for demonstrating the hard tissue formation abilities of pulp-capping materials with convenient inflammatory conditions.

The Effect of Chitosan Incorporation on Physico-Mechanical and Biological Characteristics of a Calcium Silicate Filling Material

OBJECTIVES

A tricalcium silicate-based cement, Biodentine™, has displayed antibiofilm activity when mixed with chitosan powder. This study aimed to assess the effect of chitosan incorporation on the physico-mechanical and biological properties of Biodentine™.

METHODS

In this study, medium molecular weight chitosan powder was incorporated into Biodentine™ in varying proportions (2.5 wt%, 5 wt%, 10 wt%, and 20 wt%). The setting time was determined using a Vicat apparatus, solubility was assessed by calculating weight variation after water immersion, radiopacity was evaluated and expressed in millimeters of aluminum, the compressive strength was evaluated using an Instron testing machine, and the microhardness was measured with a Vickers microhardness tester. In addition, surface topography of specimens was analyzed using scanning electron microscopy, and the effect of chitosan on the viability of human embryonic kidney (HEK 293) cells was measured by a colorimetric MTT assay.

RESULTS

Incorporation of 2.5 wt% and 5 wt% chitosan powder delivered an advantage by speeding up the setting time of Biodentine material. However, the incorporation of chitosan compromised all other material properties and the crystalline structure in a dose-dependent manner. The chitosan-modified material also showed significant decreases in the proliferation of the HEK 293 cells, signifying decreased biocompatibility.

SIGNIFICANCE

Chitosan incorporation into calcium silicate materials adversely affects the physical and biological properties of the material. Despite the increased antimicrobial activity of the modified material, the diminution in these properties is likely to reduce its clinical value.

Epigenetic therapeutics in dental pulp treatment: Hopes, challenges and concerns for the development of next-generation biomaterials

This opinion-led review paper highlights the need for novel translational research in vital-pulp-treatment (VPT), but also discusses the challenges in translating evidence to clinics. Traditional dentistry is expensive, invasive and relies on an outmoded mechanical understanding of dental disease, rather than employing a biological perspective that harnesses cell activity and the regenerative-capacity. Recent research has focussed on developing minimally-invasive biologically-based 'fillings' that preserve the dental pulp; research that is shifting the paradigm from expensive high-technology dentistry, with high failure rates, to smart restorations targeted at biological processes. Current VPTs promote repair by recruiting odontoblast-like cells in a material-dependent process. Therefore, exciting opportunities exist for development of next-generation biomaterials targeted at regenerative processes in the dentin-pulp complex. This article analyses recent research using pharmacological-inhibitors to therapeutically-target histone-deacetylase (HDAC) enzymes in dental-pulp-cells (DPCs) that stimulate pro-regenerative effects with limited loss of viability. Consequently, HDAC-inhibitors have the potential to enhance biomaterial-driven tissue responses at low concentration by influencing the cellular processes with minimal side-effects, providing an opportunity to develop a topically-placed, inexpensive bio-inductive pulp-capping material. Despite positive results, clinical translation of these innovations requires enterprise to counteract regulatory obstacles, dental-industry priorities and to develop strong academic/industry partnerships. The aim of this opinion-led review paper is to discuss the potential role of therapeutically-targeting epigenetic modifications as part of a topical VPT strategy in the treatment of the damaged dental pulp, while considering the next steps, material considerations, challenges and future for the clinical development of epigenetic therapeutics or other 'smart' restorations in VPT.

Inflammatory response and odontogenic differentiation of inflamed dental pulp treated with different pulp capping materials: An in vivo study

AIM

Previous studies have evaluated the pulpal responses to calcium silicate cements (CSCs) on normal dental pulp, but investigations on the effects of CSCs on inflamed pulp are limited. This study aimed to test the inflammatory response and odontogenic differentiation of inflamed rat dental pulp after direct pulp capping with CSCs.

METHODOLOGY

Wistar rat molars pulps were exposed for 48 h to induce inflammation and then capped with ProRoot MTA (Dentsply), Biodentine (Septodont), RetroMTA (Bio MTA) and Dycal (Dentsply Caulk). The degree of pulpal inflammation and hard tissue formation was evaluated by histological analysis. Immunofluorescence staining for interleukin (IL)-6, osteocalcin (OCN) and runt-related transcription factor 2 (RUNX2) was also performed.

RESULTS

After 4 weeks, complete recovery from inflammation was evident in 22%, 37.5%, 10% and none of the ProRoot MTA, Biodentine, RetroMTA and Dycal samples, respectively. Heavy hard tissue deposition as a continuous hard tissue bridge was observed in 77.8%, 75%, 70% and 60% of the ProRoot MTA, Biodentine, RetroMTA and Dycal samples, respectively. IL-6, OCN and RUNX2 were detected in all materials, mainly adjacent to areas of inflammation and reparative dentine formation. At one, two and 4 weeks, significant differences were not observed between the inflammation and hard tissue formation scores of the four material groups (p > .05).

CONCLUSIONS

In this study, pulpal inflammation was still present in most specimens at 4 weeks after pulp capping and a significant number of samples showed incomplete and discontinuous dentine bridge formation. The results of this study suggest that initial inflammatory conditions of the pulp may risk the prognosis of teeth treated with CSCs.

Comparative Biocompatibility and Odonto-/Osteogenesis Effects of Hydraulic Calcium Silicate-Based Cements in Simulated Direct and Indirect Approaches for Regenerative Endodontic Treatments: A Systematic Review

BACKGROUND

Regenerative dentistry is the operation of restoring dental, oral and maxillofacial tissues. Currently, there are no guidelines for the ideal cement/material in regenerative endodontic treatments (RET). Hydraulic calcium silicate-based cements (hCSCs) are currently the material of choice for RET.

OBJECTIVES

This systematic review was conducted to gather all of the different direct and indirect approaches of using hCSCs in RET in vitro and in vivo, and to ascertain if there are any superiorities to indirect approaches.

METHODS AND MATERIALS

This systematic review was conducted according to the 2020 PRISMA guidelines. The study question according to the PICO format was as follows: Comparison of the biological behavior (O) of stem cells (P) exposed to hCSCs through direct and indirect methods (I) with untreated stem cells (C). An electronic search was executed in Scopus, Google Scholar, and PubMed.

RESULTS

A total of 78 studies were included. Studies were published between 2010 and 2022. Twenty-eight commercially available and eighteen modified hCSCs were used. Seven exposure methods (four direct and three indirect contacts) were assessed. ProRoot MTA and Biodentine were the most used hCSCs and had the most desirable results. hCSCs were either freshly mixed or set before application. Most studies allowed hCSCs to set in incubation for 24 h before application, which resulted in the most desirable biological outcomes. Freshly mixed hCSCs had the worst outcomes. Indirect methods had significantly better viability/proliferation and odonto-/osteogenesis outcomes.

CONCLUSION

Biodentine and ProRoot MTA used in indirect exposure methods result in desirable biological outcomes.

DENTAL PATIENT-REPORTED OUTCOMES IN ENDODONTICS - A NARRATIVE REVIEW

Recently in oral health care settings, the focus of assessing treatment outcomes has shifted from the perspective of the clinician towards that of the patient. Endodontology is a specialty of dentistry concerned with the prevention and treatment of pulp and periapical diseases. Research in endodontology and its associated treatment outcomes have focused mainly on clinician-reported outcomes (CROs) and not dental patient-reported outcomes (dPROs). As a result, there is a need to emphasize the importance and relevance of dPROs to researchers and clinicians. The aim of this review is to present an overview of dPROs and dPROMs within endodontics in an attempt to create a better understanding of the patient experience, highlight the need to place the patient at the center of treatment, enhance patient care and encourage more research into dPROs. The key dPROs following endodontic treatment include pain, tenderness, tooth function, need for further intervention, adverse effects (exacerbation of symptoms, tooth discoloration) and Oral Health-Related Quality of Life. dPROs are important following endodontic treatment because they assist clinicians and patients when they discuss and select the most appropriate management options, help clinicians make decisions on pre-operative assessment, prevention and treatment, and improve the methodology and design of future clinical studies. Clinicians and researchers in endodontology should prioritize patient welfare and undertake routine analyses of dPROs using appropriate and robust measures. Due to the lack of agreement over the reporting and definition of endodontic treatment outcomes, a comprehensive project to define a ``Core Outcome Set for Endodontic Treatment Methods (COSET)'' is currently ongoing. In the future, a new and exclusive assessment tool should be developed to reflect the viewpoints of patients receiving endodontic treatment more accurately.

A prospective clinical study investigating the effectiveness of partial pulpotomy after relating preoperative symptoms to a new and established classification of pulpitis

AIM

To prospectively investigate the outcome of partial pulpotomy after 1 year, using a hydraulic calcium silicate cement (HCSC) on symptomatic cariously exposed pulps in adult teeth. To compare the traditional American Association of Endodontists (AAE) pulpitis classification with the recently proposed Wolters classification system in predicting the likelihood of treatment failure.

METHODOLOGY

Sixty-two symptomatic adult teeth with deep and extremely deep carious lesions were classified according to the Wolters (mild/moderate/severe pulpitis) and the traditional pulpitis classification (reversible/irreversible pulpitis). Eleven teeth were excluded intraoperatively as there was no pulp exposure after non-selective caries removal. The remaining 51 teeth, regardless of diagnosis, were treated by partial pulpotomy, pulpal lavage with 2.5% sodium hypochlorite solution, haemostasis and HCSC application (Biodentine™) as a pulp capping material. A permanent restoration was placed during a second appointment 1-2 weeks later. Preoperative tenderness to percussion (TTP), bleeding time and material setting time were recorded as was preoperative and postoperative tooth colour under standardized conditions. Clinical review occurred at regular intervals with clinical/radiographic analysis at 12 months. Chi-square analysis and Fisher's exact test assessed different outcomes amongst the diagnostic categories; the Kruskal-Wallis and Wilcoxon rank-sum test assessed influence of pulp bleeding time, TTP or variation in setting time (p < .05).

RESULTS

Ten cases were lost to review, and a total of 41 teeth were reviewed at 1 year and classified as either "success," "successful but unresponsive to sensibility testing" or "failed." This included five severe, 17 moderate and 19 mild pulpitis according to Wolters classification or 23 reversible pulpitis and 18 irreversible pulpitis cases by the AAE classification. The majority of the 62 enrolled cases were "extremely deep" (n = 50), rather than "deep" (n = 12) caries with all failures occurring in the extremely deep group. Partial pulpotomy was 90% successful (100% reversible, 78% irreversible or 100% mild, 88% moderate, 60% severe pulpitis) with a significant difference in outcome between mild and severe pulpitis groups (p = .04). Only one, severe pulpitis/irreversible pulpitis, case failed painfully prior to the 1-year review appointment. Bleeding time (p = .26) and TTP (p = .61) did not influence treatment outcome, whilst Biodentine™ setting time was significantly longer than manufacturers' claim (p < .05). No teeth discoloured.

CONCLUSIONS

Partial pulpotomy using Biodentine™ was successful for treating symptomatic carious pulpal exposures after 1 year, but included cases where pulp vitality could not be confirmed. Within the limitations of this study, cases with signs and symptoms indicative of irreversible pulpitis were not less successful; however, Wolters classification highlighted severe pulpitis to be less successful than mild pulpitis, thereby providing a potential prognostic benefit in diagnostically subdividing pulpitis. Caries depth was an indicator of failure, whilst bleeding time and preoperative tenderness to percussion were not.

Reducing Intervention in the COVID-19 Era: Opportunities for Vital Pulp Treatment

Over the last 12 months, the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-COV-2) virus has emerged as a significant global health problem with extensive repercussions for the practise of dentistry. As the principle transmission-route is via droplet-spread, aerosol-generating dental procedures (AGPs) present an exquisite challenge, which either has to be avoided or performed using strict infection-control measures, which increase the deployment of resources and cost. This new working environment necessitates the adoption of simplified, yet effective procedures that reduce intervention and minimise clinical chair time to short, single visits. Vital pulp treatment (VPT) has emerged as an attractive, technically less-complicated group of biologically-based management strategies that are aimed at maintaining pulp vitality and avoiding root canal treatment (RCT). These procedures are carried out in a strict aseptic environment using a rubber dam and have a reported high success rate, suggesting that they could be considered as effective and simple alternative therapies to relieve pain and avoid multiple visit RCT and other endodontic procedures. The relevance of promoting a simple, predictable and effective alternative to traditional, more complex dentistry has never been more compelling. In this perspective article, the latest advances in VPT are highlighted, along with an analysis of their relative success and compelling reasons why we as dentists should be adopting these treatment approaches. Thereafter, case selection, prognostic factors, techniques, limitations and future prospects of these procedures are discussed.

Evaluation of Reparative Dentine Bridge Formation after Direct Pulp Capping with Biodentine

Aim:

To evaluate the capability of Biodentine for direct pulp capping in permanent teeth.

Materials and Methods:

The pulp of 11 human intact premolars were mechanically exposed in standard cavity dimensions and then capped with Biodentine for direct pulp capping. After 9–12 weeks, all teeth were extracted. All teeth were scanned using intraoral radiograph or cone-beam computed tomography (CBCT) scan before, right after pulp capping therapy, and after 9–12 weeks on both patient real and extracted teeth for evaluation of reparative dentin bridge formation. All clinical symptoms and signs were also recorded. Data were collected and analyzed using the MedCal statistical software at the significance of 0.05.

Results:

There was reparative dentin bridge formation in all experimental teeth, on both patient real and extracted teeth.

Conclusions:

The Biodentine could induce the formation of reparative dentin in direct pulp capping. The CBCT scan was the reliable modality for evaluation of dentin bridge formation.

Efficacy of direct pulp capping for management of cariously exposed pulps in permanent teeth: a systematic review and meta-analysis

BACKGROUND

The outcome of vital pulp treatment after carious pulp exposure is multifactorial and related to the procedure, biomaterial and pre-operative pulpal diagnosis.

OBJECTIVES

To conduct a systematic review and meta-analysis determining the outcome of direct pulp capping (DPC) in mature permanent teeth with a cariously exposed pulp and a clinical diagnosis of reversible pulpitis, and ascertain whether the capping material influences the outcome.

METHODS

Sources: MEDLINE Ovid-SP, Cochrane Central Register of Controlled Trials (CENTRAL), International Clinical Trials Registry Platform (ICTRP), ClinicalTrials.gov, Embase and Web of Science until April 2020. Inclusion: Prospective, retrospective cohort studies and randomized trials investigating DPC outcome or comparing different capping materials after carious pulp exposure. Exclusion: Primary teeth, mechanical, traumatic or not specified pulp exposure, teeth with irreversible pulpitis or no pulpal diagnosis. Risk of bias assessed using Cochrane and modified Downs and Black quality assessment checklist. Meta-analysis on combined clinical/radiographic outcome was performed using a random effect model. Success was defined as absence of signs and symptoms of irreversible pulpitis, apical periodontitis or loss of pulp vitality.

RESULTS

Quality assessment highlighted four non-randomized studies to be of fair and five of poor quality. Four randomized trials had a high risk of bias. The pooled success rate differed based on material and follow-up. Calcium hydroxide success rate was 74% at 6-months, 65% at 1-year, 59% at 2-3 years and 56% at 4-5 years. Mineral trioxide aggregate (MTA) success was 91%, 86%, 84% and 81% at the same time points. Biodentine success was 96% at 6-months, 86% at 1 year and 86% at 2-3 years. The meta-analysis revealed MTA had better success than calcium hydroxide at 1-year (OR 2.66, 95% CI; 1.46- 4.84, P = 0.001) and 2- to 3-year follow-up (OR 2.21, 95% CI; 1.42-3.44, P = 0.0004). There was no difference between MTA and Biodentine.

DISCUSSION

These results were based on poor methodological quality studies. The effect size for of MTA vs Ca(OH)2, although modest, was consistent with narrow CI.

CONCLUSIONS

Low-quality evidence suggests a high success rate for direct pulp capping in teeth with cariously exposed pulps with better long-term outcomes for MTA and Biodentine compared with calcium hydroxide.

The management of deep carious lesions and the exposed pulp amongst members of two European endodontic societies: a questionnaire-based study

AIMS

To investigate and compare views on management of deep caries and the exposed pulp by Endodontic Society members in Ireland (Irish Endodontic Society [IES]) and Italy (Accademia Italiana di Endodonzia [AIE]). Further aims were to investigate the influence of patient-related factors (age, symptoms) and operator-related factors (material choice, antibiotics) on management.

METHODOLOGY

A structured online questionnaire containing two cases (an 18- and 45-year-old) and two scenarios (± mild symptoms), including history and radiograph, was sent to IES and AIE members. The answers were analysed using chi-square and Fisher's exact test (P < 0.05).

RESULTS

In total, 120 dentists participated, representing 49% of the AIE and 48% of the IES membership. Age distribution was similar between the societies; however, most AIE members had no further qualifications (63%), while IES respondents generally had a postgraduate endodontic qualification (71%). AIE respondents carried out a larger volume of vital pulp treatment (VPT) per month, with 69% carrying out over five cases, compared with 22% of IES respondents. The presence of patient symptoms significantly altered treatment planning decisions (P < 0.001) with root canal treatment (RCT) more frequently selected in both societies. Patient age significantly influenced treatment choice in the absence (P = 0.043) or presence (P = 0.012) of symptoms with less VPT advocated in older patients. There were no significant differences in the treatment of a young patient in the presence (P = 0.302) or absence of symptoms (P = 0.297); however, older patient management differed between the societies for symptomatic (P = 0.041) and asymptomatic scenarios (P = 0.044) with significantly more RCTs carried out in the AIE than the IES. Hydraulic calcium silicate materials were commonly selected, accounting for 81% of IES and 69% of AIE VPT materials, although younger members of the AIE preferred calcium hydroxide materials. Younger dentists in both societies prescribed less RCT than older age groups.

CONCLUSIONS

Although VPT is carried out by members of both societies there was no consistency regarding the most appropriate management for the exposed pulp or the VPT material of choice. Patient symptoms and age significantly influence the decision-making process and invasiveness of treatment. Hydraulic calcium silicate materials were the most commonly advocated material in all groups except young AIE members who preferred calcium hydroxide.

Physicochemical, antimicrobial, and biological properties of White-MTAFlow

OBJECTIVES

To evaluate a new material containing tantalum oxide as an alternative radiopacifier, and a water-based gel for hydration, in comparison with two calcium silicate-based cement: ProRoot MTA and Biodentine.

MATERIALS AND METHODS

ProRoot MTA (Dentsply), Biodentine (Septodont), and a new hydraulic calcium silicate cement White-MTAFlow (Ultradent) (in 'thin' consistency) were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS). The interaction with dentin was also assessed using SEM and EDS. Physical and chemical properties radiopacity, setting time, linear flow, volumetric central filling, and lateral flow, pH, and volume change were investigated together with the color luminosity (L) and color change (ΔE). The agar diffusion and direct contact antimicrobial activity, and methylthiazolyldiphenyl-tetrazolium-bromide (MTT) cytotoxicity using human fibroblast cells were also evaluated. Data were statistically analyzed at a 5% significance level.

RESULTS

All materials were composed of tricalcium and dicalcium silicate but had different radiopacifiers, and calcium hydroxide (portlandite) deposition was detected in XRD analysis. White-MTAFlow exhibited radiopacity values in accordance with ISO standard, and the longest setting time. The water-based gel provided the highest linear flow, a comparable cavity central filling, and the highest groove-lateral flow in the volumetric flow analysis. White-MTAFlow exhibited an alkalinity reduction, and Biodentine, a progressive increase of pH values after 28 days. However, similar volume loss for White-MTAFlow was assessed in comparison to Biodentine after the 28-day immersion. White-MTAFlow showed the highest L value (91.5), and ProRoot MTA the lowest (78.1) due to dentin staining caused by bismuth migration. None of the materials exhibited inhibition halos against the tested bacteria, and similar turbidity values were obtained after 48 h in direct contact with E. faecalis, indicating an upregulation to bacterial growth. White-MTAFlow showed MTT cytocompatibility similarly to the control group.

CONCLUSIONS

White-MTAFlow in 'thin' consistency presents comparable physicochemical, biological, and antimicrobial properties to ProRoot MTA and Biodentine, and does not cause color alteration in dentin.

CLINICAL RELEVANCE

White-MTAFlow is a suitable material for use as reparative endodontic cement. Further studies considering its biocompatibility are necessary.

Bioactivity assessment of bioactive glasses for dental applications: A critical review

OBJECTIVE

In the context of minimally invasive dentistry and tissue conservation, bioactive products are valuable. The aim of this review was to identify, clarify, and classify the methodologies used to quantify the bioactive glasses bioactivity.

METHODS

Specific search strategies were performed in electronic databases: PubMed, Embase, Cochrane Library, and Scopus. Papers were selected after a review of their title, abstract, and full text. The following data were then examined for final selection: BAG investigated, objectives, criteria, methods, and outcomes.

RESULTS

Sixty-one studies published from 2001 to 2019, were included. The bioactivity of BAG can be evaluated in vitro in contact with solutions, enamel, dentin, or cells. Other studies have conducted in vivo evaluation by BAG contact with dentin and dental pulp. Studies have used various analysis techniques: evaluation of apatite with or without characterization or assessment of mechanical properties. Reprecipitation mechanisms and pulp cell stimulation are treated together through the term 'bioactivity'.

SIGNIFICANCE

Based on these results, we suggested a classification of methodologies for a better understanding of the bioactive properties of BAG. According to all in vitro studies, BAG appear to be bioactive materials. No consensus has been reached on the results of in vivo studies, and no comparison has been conducted between protocols to assess the bioactivity of other bioactive competitor products.

Management of deep caries and the exposed pulp

Caries prevalence remains high throughout the world, with the burden of disease increasingly affecting older and socially disadvantaged groups in Western cultures. If left untreated, caries will advance through dentine stimulating pulpitis and eventually pulp infection and necrosis; however, if conservatively managed, pulpal recovery occurs even in deep carious lesions. Traditionally, deep caries management was destructive with nonselective (complete) removal of all carious dentine; however, the promotion of minimally invasive biologically based treatment strategies has been advocated for selective (partial) caries removal and a reduced risk of pulp exposure. Selective caries removal strategies can be one-visit as indirect pulp treatment or two-visit using a stepwise approach. Management strategies for the treatment of the cariously exposed pulp are also shifting with avoidance of pulpectomy and the re-emergence of vital pulp treatment (VPT) techniques such as partial and complete pulpotomy. These changes stem from an improved understanding of the pulp-dentine complex's defensive and reparative response to irritation, with harnessing the release of bioactive dentine matrix components and careful handling of the damaged tissue considered critical. Notably, the development of new pulp capping materials such as mineral trioxide aggregate, which although not an ideal material, has resulted in more predictable treatments from both a histological and a clinical perspective. Unfortunately, the changes in management are only supported by relatively weak evidence with case series, cohort studies and preliminary studies containing low patient numbers forming the bulk of the evidence. As a result, critical questions related to the superiority of one caries removal technique over another, the best pulp capping biomaterial or whether pulp exposure is a negative prognostic factor remain unanswered. There is an urgent need to promote minimally invasive treatment strategies in Operative Dentistry and Endodontology; however, the development of accurate diagnostic tools, evidence-based management strategies and education in management of the exposed pulp are critical in the future.