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.

Factors Affecting the Decision-Making of Direct Pulp Capping Procedures Amongst Dental Practitioners: A Multinational Survey from 16 Countries with Meta-Analysis

BACKGROUND

Direct pulp capping (DPC) procedures require the placement of a bioactive material over an exposure site without selective pulp tissue removal. This web-based multicentered survey had three purposes: i) to investigate the factors that affect clinicians' decisions in DPC cases, ii) to determine which method of caries removal is preferred, and iii) to evaluate the preferred capping material for DPC.

METHODS

The questionnaire comprised three sections. The first part comprised questions regarding demographic features. The second part comprised questions on how treatment plans change according to factors such as nature, location, number and size of the pulp exposure and patients' age. The third part composed of questions on the common materials and techniques used in DPC. To estimate the effect size, the risk ratio (RR) and 95% confidence interval (CI) were calculated using a meta-analysis software.

RESULTS

A tendency towards more invasive treatment was observed for the clinical scenario with carious-exposed pulp (RR=2.86, 95% CI:2.46,2.32; p<0.001) as opposed to the clinical scenario with two pulp exposures (RR=1.38, 95% CI:1.24,1.53; p<0.001). Complete caries removal was significantly preferred to selective caries removal (RR=4.59, 95% CI: 3.70, 5.69; p<0.001). Among the capping materials, calcium silicate-based materials (CS) were preferred over calcium hydroxide-based materials (CH) (RR=0.58, 95% CI: 0.44,0.76; p<0.05).

CONCLUSION

While carious-exposed pulp is the most important factor in clinical decisions regarding DPC, the number of exposures has the least impact. Overall, complete caries removal was preferred over selective caries removal. In addition, the use of CS appears to have replaced CH.

Evaluation of Endosequence Root Repair Material and Endocem MTA as direct pulp capping agents: An in vivo study

The study aimed to assess the human pulpal response to direct pulp capping using Endosequence Root Repair Material (ERRM) and Endocem MTA against ProRoot MTA as control. Intentional direct pulp capping was done using the three materials in 30 caries-free human premolars. After 30 days, the teeth were extracted, fixed and decalcified. Sections were prepared for histologic examination using light microscopy. Thickness and quality of dentine bridge formed and level of inflammation were evaluated. Difference between dentine bridge thickness of the three groups was statistically significant. Mean thickness of dentine bridges formed in ProRoot MTA group was greater than other two groups, and difference was statistically significant. Difference in dentine bridge thickness between ERRM and Endocem MTA was statistically significant. No significant difference was observed between the 3 groups with respect to inflammation. Results indicate ProRoot MTA performed best with ERRM giving better results than Endocem MTA.

Preserving pulp vitality: part two - vital pulp therapies

Vital pulp therapies (VPTs) aim to preserve the vitality of the pulp. The European Society of Endodontology have begun a campaign to raise awareness on the efficacy of VPTs following on from the publication of their 2019 position statement, aimed at both specialists and general dental practitioners. This review examines the current evidence surrounding VPTs and provides a rational approach to the management of the exposed pulp with the aid of case studies. Success lies in accurate diagnosis and case selection, along with well-executed treatment and appropriate follow-up protocols. The introduction of calcium silicate cements has made these treatments more predictable.

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.

Protein S100-A7 Derived from Digested Dentin Is a Critical Molecule for Dentin Pulp Regeneration

Dentin consists of inorganic hard tissue and organic dentin matrix components (DMCs). Various kinds of bioactive molecules are included in DMCs and some of them can be released after digestion by endogenous matrix metalloproteinases (MMPs) in the caries region. Digested DMCs induced by MMP20 have been reported to promote pulpal wound healing processes, but the released critical molecules responsible for this phenomenon are unclear. Here, we identified protein S100-A7 as a critical molecule for pulpal healing in digested DMCs by comprehensive proteomic approaches and following pulp capping experiments in rat molars. In addition, immunohistochemical results indicated the specific distribution of S100-A7 and receptor for advanced glycation end-products (RAGE) as receptor for S100-A7 in the early stage of the pulpal healing process, and following accumulation of CD146-positive stem cells in wounded pulp. Our findings indicate that protein S100-A7 released from dentin by MMP20 might play a key role in dentin pulp regeneration.

Biodentine™ Boosts, WhiteProRoot®MTA Increases and Life® Suppresses Odontoblast Activity

(1) Background: When pulp exposure occurs, reparative dentinogenesis can be induced by direct pulp capping to maintain the vitality and function of the tissue. The aim of this work was to assess the cytotoxicity and bioactivity of three different direct pulp capping materials, calcium hydroxide (Life^®), mineral trioxide aggregate (WhiteProRoot^®MTA) and calcium silicate (Biodentine^™), in an odontoblast-like mouse cell line (MDPC-23). (2) Methods: Metabolic activity was assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test (MTT)assay, viability by the sulforhodamine B (SRB) assay, and the type of death and cell cycle analysis by flow cytometry. Alkaline phosphatase was evaluated by polymerase chain reaction (PCR), and dentin sialoprotein expression was assessed by immunocytochemistry. Mineralization was determined by the Alizarin Red S colorimetric assay and quantified by spectrophotometry. (3) Results: Life^® induced a decrease in metabolic activity and viability, which is associated with an increase cell death. WhiteProRoot^®MTA and Biodentine™ induced similar effects in cytotoxicity assays, with an increase in the expression of dentin sialoprotein (DSP) and formation of mineralized deposits, especially with Biodentine™. (4) Conclusions: The results of WhiteProRoot^®MTA confirm its indication for these therapies, justifying its recognition as the “gold standard”. Biodentine™ may be an alternative, since they promote the same cellular response that mineral trioxide aggregate (MTA) does.

Anti-inflammatory and Mineralization Effects of ProRoot MTA and Endocem MTA in Studies of Human and Rat Dental Pulps In Vitro and In Vivo

INTRODUCTION

Few studies have reported direct pulp capping in inflamed pulp conditions. The purpose of this study was to investigate the in vitro and in vivo responses of dental pulp during direct pulp capping using various pulp capping materials in inflamed conditions.

METHODS

Human dental pulp cells were treated with lipopolysaccharide (LPS) and cultured with Dycal (Dentsply Caulk, Milford, DE), ProRoot MTA (Dentsply Maillefer, Ballaigues, Switzerland), and Endocem MTA (Maruchi, Wonju, South Korea). The expressions of interleukin (IL)-1β, IL-6, dentin matrix protein 1, and dentin sialophosphoprotein were analyzed through real-time polymerase chain reaction. The maxillary molars of Sprague-Dawley rats were exposed for 2 days. The exposed pulps were capped with Dycal, ProRoot MTA, and Endocem MTA and sealed with resin-modified glass ionomer followed by histologic and immunohistochemical analyses.

RESULTS

The expression of IL-1β and IL-6 was increased with LPS and decreased by Dycal, ProRoot MTA, and Endocem MTA. Dentin matrix protein 1 and dentin sialophosphoprotein levels were decreased with LPS and increased after treatment with pulp capping materials.In the in vivo study, inflammation associated with Dycal was higher than that associated with ProRoot MTA and Endocem MTA at week 1, without any significant difference between the 2. At 4 weeks, inflammation was decreased, and mineralization was increased compared with week 1 in all 3 of the materials. At week 1, IL-6 immunoreactivity was strongly expressed. Dycal exhibited stronger immunoreactivity than ProRoot MTA and Endocem MTA. However, the immunoreactivity was decreased in all groups at week 4.

CONCLUSIONS

Successful direct pulp capping requires more effective pulp capping materials for the treatment of inflamed pulps.

Direct Pulp Capping: What is the Most Effective Therapy?-Systematic Review and Meta-Analysis

INTRODUCTION

Direct pulp capping therapies use biomaterials to protect exposed tissues, inducing repair through the production of a mineralized barrier. The purpose of this study was to compare the effectiveness of biomaterials and techniques by means of a systematic review and meta-analysis.

METHODS

The PubMed, Cochrane, and Embase databases were used to search the literature published from January 1, 1980 until August 31, 2017. Studies that met inclusion criteria were screened by 2 authors individually. The meta-analysis was performed on mineral trioxide aggregate (MTA) cement vs calcium hydroxide cement, tricalcium silicate cement vs MTA cement, and adhesive systems vs CaOH cement and evaluated the success rate, inflammatory response, and dentin bridge formation.

RESULTS

Forty-six studies were included in the systematic review, while 22 studies were included in the meta-analysis. There was no significant heterogeneity between the studies. MTA cements showed a significantly higher success rate, in all parameters, compared with calcium hydroxide cements (odds ratio = 2.72; 95% confidence interval [CI] = 1.90-3.90; P = 0.000). However, when compared with the tricalcium silicate cements, there were no statistically significant differences (odds ratio = 1.18; 95% CI = 0.53-2.65; P = 0.672). Adhesive systems showed a significantly lower success rate, in all parameters, compared with calcium hydroxide cements (odds ratio = 0.062; 95% CI = 0.024-0.157; P = 0.000).

CONCLUSIONS

MTA cements have a higher success rate, with a lower inflammatory response and a more predictable hard dentin barrier formation than calcium hydroxide cements. However, there were no differences, in these parameters, when MTA cement was compared with tricalcium silicate cements. Dental adhesives systems showed the lowest success rates.

Outcomes of Direct Pulp Capping by Using Either ProRoot Mineral Trioxide Aggregate or Biodentine in Permanent Teeth with Carious Pulp Exposure in 6- to 18-Year-Old Patients: A Randomized Controlled Trial

INTRODUCTION

This study aimed to compare the success rates of direct pulp capping (DPC) by using either ProRoot Mineral Trioxide Aggregate (MTA) or Biodentine in the cariously exposed permanent teeth of 6- to 18-year-old patients. Gray discoloration was also evaluated.

METHODS

Fifty-nine cariously exposed permanent teeth, including teeth with diagnosis of normal pulp, reversible pulpitis, or irreversible pulpitis, early periapical involvement, and exposure size of up to 2.5 mm, were included. Each patient with only 1 cariously exposed tooth was randomly allocated to DPC with either ProRoot MTA (n = 30) or Biodentine (n = 29). Patients were recalled every 6 months. Clinical and radiographic examinations were used to determine success.

RESULTS

Fifty-five patients (mean age, 10 ± 2 years), 27 treated with ProRoot MTA and 28 with Biodentine, were included in the analysis. At mean follow-up of 18.9 ± 12.9 months, the success rate was 92.6% with ProRoot MTA and 96.4% with Biodentine (P > .05; difference, 4%; 95% confidence interval [CI], -8% to 16%). Biodentine was non-inferior to ProRoot MTA. Failures were distributed equally in all categories of pulpal diagnosis and occurred in teeth with no periapical involvement and small exposures (0.5 mm). The survival probabilities of DPC with ProRoot MTA and Biodentine were 0.92 (95% CI, 0.73-0.98) and 0.96 (95% CI, 0.80-0.99). No significant difference was observed between them (P > .05). Gray discoloration was observed only with ProRoot MTA (55%).

CONCLUSIONS

Biodentine was non-inferior to ProRoot MTA when used as a DPC material for cariously exposed permanent teeth of 6- to 18-year-old patients. However, Biodentine did not cause any gray discoloration in this study.

Mineral trioxide aggregate and other bioactive endodontic cements: an updated overview - part I: vital pulp therapy

Mineral trioxide aggregate (MTA) is a bioactive endodontic cement (BEC) mainly comprised of calcium and silicate elements. The cement was introduced by Torabinejad in the 1990s and has been approved by the Food and Drug Administration to be used in the United States in 1997. A number of new BECs have also been introduced to the market, including BioAggregate, Biodentine, BioRoot RCS, calcium-enriched mixture cement, Endo-CPM, Endocem, EndoSequence, EndoBinder, EndoSeal MTA, iRoot, MicroMega MTA, MTA Bio, MTA Fillapex, MTA Plus, NeoMTA Plus, OrthoMTA, Quick-Set, RetroMTA, Tech Biosealer and TheraCal LC. It has been claimed that these materials have properties similar to those of MTA without its drawbacks. In this article, the chemical composition and the application of MTA and other BECs for vital pulp therapy (VPT), including indirect pulp cap, direct pulp cap, partial pulpotomy, pulpotomy and partial pulpectomy, have been reviewed and compared. Based on selected keywords, all papers regarding chemical composition and VPT applications of BECs had been reviewed. Most of the materials had calcium and silicate in their composition. Instead of referring to the cements based on their chemical compositions, we suggest the term 'bioactive endodontic cements (BECs)', which seems more appropriate for these materials because, in spite of differences in their chemical compositions, bioactivity is a common property for all of them. Numerous articles were found regarding use of BECs as VPT agents for indirect and direct pulp capping, partial pulpotomy and cervical pulpotomy. Most of these investigations used MTA for VPT. In most studies, newly introduced materials have been compared to MTA. Some of the BECs have shown promising results; however, the number of their studies compared to investigations on MTA is limited. Most studies had several methodological shortcomings. Future investigations with rigorous methods and materials are needed.

Current status of direct pulp-capping materials for permanent teeth

Direct pulp-capping is a method for treating exposed vital pulp with dental material to facilitate the formation of reparative dentin and to maintain vital pulp. Two types of pulp-capping materials, calcium hydroxide and mineral trioxide aggregate, have been most commonly used in clinics, and an adhesive resin has been considered a promising capping material. However, until now, there has been no comprehensive review of these materials. Therefore, in this paper, the composition, working mechanisms and clinical outcome of these types of pulp-capping materials are reviewed.

Capping carious exposures in adults: a randomized controlled trial investigating mineral trioxide aggregate versus calcium hydroxide

AIM

The aim of this multicentre, parallel-group randomized clinical trial was to compare the effectiveness of mineral trioxide aggregate (MTA) and a conventional calcium hydroxide liner (CH) as direct pulp capping materials in adult molars with carious pulpal exposure.

METHODOLOGY

Seventy adults aged 18-55 years were randomly allocated to two parallel arms: MTA (White ProRoot, Dentsply, Tulsa Dental, Tulsa, OK, USA; n = 33) and CH (Dycal^® , Dentsply DeTrey GmbH, Konstanz, Germany; n = 37). The teeth were temporized for 1 week with glass-ionomer (Fuji IX, GC Corp, Tokyo, Japan) and then permanently restored with a composite resin. The subjects were followed up after 1 week and at six, 12, 24 and 36 months. The primary outcome was the survival of the capped pulps, and the secondary outcome was postoperative pain after 1 week. Survival was defined as a nonsymptomatic tooth that responded to sensibility testing and did not exhibit periapical changes on radiograph. At each check-up, the pulp was tested for sensibility and a periapical radiograph was taken (excluding the radiographs taken at the 1-week follow-up). Kaplan-Meier survival analysis and log-rank test were used to assess the significant difference in the survival curves between groups. Chi-square test was used to assess the association between the materials and preoperative and postoperative pain.

RESULTS

At 36 months, the Kaplan-Meier survival analysis showed a cumulative estimate rate of 85% for the MTA group and 52% for the CH group (P = 0.006). There was no significant association between the capping material and postoperative pain.

CONCLUSIONS

Mineral trioxide aggregate performed more effectively than a conventional CH liner as a direct pulp capping material in molars with carious pulpal exposure in adult patients. This study has been registered at ClinicalTrials.gov, number NCT01224925.

Outcomes of direct pulp capping: interrogating an insurance database

AIM

To evaluate the effectiveness of direct pulp capping under general practice conditions. It was hypothesized that direct pulp capping is an effective procedure in the majority of cases and prevents the need for root canal treatment or extraction.

METHODOLOGY

Claims data were collected from the digital database of a major German national health insurance company. Only patients who had been insurance members for the entire 3 year period 2010 to 2012 were eligible. Kaplan-Meier survival analyses were conducted for all teeth with direct pulp capping. Success was defined as not undergoing root canal treatment. Survival was defined as not undergoing extraction. Differences between survival functions were tested with the log rank test.

RESULTS

A total of 148 312 teeth were included. The overall success rate was 71.6% at 3 years. The overall survival rate was 95.9% at 3 years. The success rates for single-rooted teeth (71.8%) and multirooted teeth (71.5%) were similar although significantly different (P < 0.001). Best 3-year success rates were found at low (79.7%; <18 years.) and very high age (81.8%; >85 years.).

CONCLUSIONS

After direct pulp capping, more than two-thirds of the affected teeth did not undergo root canal treatment within 3 years. Although this study has the typical limits of a claims data analysis, it can be concluded that direct pulp capping is an effective intervention to avoid root canal treatment and extraction in a general practice setting.

Outcome of Direct Pulp Capping with Mineral Trioxide Aggregate: A Prospective Study

INTRODUCTION

The aim of this experimental study was to assess the outcome of direct pulp capping with mineral trioxide aggregate (MTA) after complete excavation of caries in permanent dentition with a 2-visit treatment protocol.

METHODS

Sixty-four teeth with deep carious lesions were consecutively selected. The mean age of the patients was 36.1 ± 15 years. An initial diagnosis of deep caries, with no irreversible pulp involvement, was made. Excavation of caries was performed under a rubber dam and operating microscope magnification. White MTA was applied, and a provisional restoration was placed. At the following appointment, positive sensibility testing and the MTA setting were confirmed. Bonded composite restorations were placed afterward. The patient was recalled at least 1 year after treatment for clinical and radiographic control. Outcome was described as success or failure. Success was defined as lack of complaints from the patient, positive reaction to cold testing, no sensitivity to percussion, and no widening of the periodontal ligament on the recall periapical radiograph.

RESULTS

Forty-six teeth (77.9%) were recalled after 3.6 years (standard deviation = 1.1 years). The overall success rate was 91.3%. The success rate in occlusal caries was 100% and 89.7% in proximal caries (difference = 10.3%; 95% confidence interval [CI], 8.5-89.1). The success rate in initial caries was 94.7% and 88.9% in secondary caries (difference = 5.8%; 95% CI, -48.1 to 59.7). The success rate in patients younger than 40 years was 100% and 80% in patients aged 40 years or older (difference = 20%; 95% CI, 4.2-35.8).

CONCLUSIONS

Direct pulp capping with MTA after pulp exposure during excavation of deep caries could maintain pulp vitality in permanent teeth when a 2-visit treatment protocol is observed.

Prognostic factors for clinical outcomes according to time after direct pulp capping

INTRODUCTION

Direct pulp capping is a treatment option for teeth with carious-exposed pulp. Because pulp capping studies have exhibited fluctuations in success rates according to different follow-up times, investigating the clinical pulpal survival rate and the potential factors contributing to the survival with respect to time is necessary.

METHODS

A total of 175 patients treated between November 2007 and August 2010 met the inclusion criteria. During the follow-up, we investigated 7 clinical variables with respect to the survival of the pulp capping treatment: sex, age, maxilla versus mandible, tooth position, capping materials, temporary filling materials, and exposure site. Survival analysis was performed using the Kaplan-Meier method and the Cox proportional hazard regression model.

RESULTS

The Kaplan-Meier survival curves and log-rank tests revealed that only age, exposure site, and capping material had significant effects on the pulpal survival rate (P< .05). A Cox regression model showed that mineral trioxide aggregate was the sole factor affecting the survival of the treated pulps (P< .05). In the analyses performed separately according to time, there was no conspicuous factor that affected the survival rate before 100 days. However, after 100 days, the type of pulp capping material was the single most important factor influencing the survival rate (P< .05).

CONCLUSIONS

The results of this study indicated that careful patient selection and the type of pulp capping material should be taken into consideration when performing a pulp capping treatment.