Human pulpal response to mineral trioxide aggregate (MTA): a histologic study

Histological evaluation of the regenerative potential of a novel photocrosslinkable gelatin-treated dentin matrix hydrogel in direct pulp capping: an animal study

BACKGROUND

To assess histologically the success of the pulp capping approach performed in traumatically exposed dogs' teeth using a novel injectable gelatin-treated dentin matrix light cured hydrogel (LCG-TDM) compared with LCG, MTA and TheraCal LC.

METHODS

Sixty-four dogs' teeth were divided into two groups (each including 32 teeth) based on the post-treatment evaluation period: group I: 2 weeks and group II: 8 weeks. Each group was further subdivided according to the pulp capping material into four subgroups (n = 8), with subgroup A (light-cured gelatin hydrogel) as the control subgroup, subgroup B (LCG-TDM), subgroup C (TheraCal LC), and subgroup D (MTA). Pulps were mechanically exposed in the middle of the cavity floor and capped with different materials. An assessment of periapical response was performed preoperatively and at 8 weeks. After 2 and 8-week intervals, the dogs were sacrificed, and the teeth were stained with hematoxylin-eosin and graded by using a histologic scoring system. Statistical analysis was performed using the chi-square and Kruskal-Wallis tests (p = 0.05).

RESULTS

All subgroups showed mild inflammation with normal pulp tissue at 2 weeks with no significant differences between subgroups (p ≤ 0.05), except for the TheraCal LC subgroup, which exhibited moderate inflammation (62.5%). Absence of a complete calcified bridge was reported in all subgroups at 2 weeks, while at 8 weeks, the majority of samples in the LCG-TDM and MTA-Angelus subgroups showed complete dentin bridge formation and absence of inflammatory pulp response with no significant differences between them (p ≤ 0.05). However, the formed dentin in the LCG-TDM group was significantly thicker, with layers of ordered odontoblasts identified to create a homogeneous tubular structure and numerous dentinal tubule lines suggesting a favourable trend towards dentin regeneration. TheraCal LC samples revealed a reasonably thick dentin bridge with moderate inflammation (50%) and LCG showed heavily fibrous tissue infiltrates with areas of degenerated pulp with no signs of hard tissue formation.

CONCLUSIONS

LCG-TDM, as an extracellular matrix-based material, has the potential to regenerate dentin and preserve pulp vitality, making it a viable natural alternative to silicate-based cements for healing in vivo dentin defects in direct pulp-capping procedures.

A paradigm shift from calcium hydroxide to bioceramics in direct pulp capping: A narrative review

For many years, calcium hydroxide (CH) was the preferred material for direct pulp capping (DPC), occupying an elevated position. The collapse of this paradigm is due to the emergence of bioceramics with less pulpal inflammation and superior mineralization abilities than CH. The goal of the current article was directed to: (1) review the history of DPC "the idea of an exposed pulp as a hopeless organ has given way to one of healing and optimism," (2) classify the bioceramics in dentistry, and (3) explain and compare the mechanism by which dentin barriers for CH and bioceramics are formed. A comprehensive literature search of the database was conducted using PubMed, Google Scholar, and Scopus utilizing the following terms: Biodentine, calcium hydroxide, calcium aluminate, calcium phosphate, calcium silicate, direct pulp capping, NeoMTA Plus, Quick-Set2, and TotalFill. Reference mining of the selected publications was utilized to discover other studies and strengthen the results. Only works written in English were taken into consideration, and there were no restrictions on the year of publication. Bioceramic materials might be used as an intriguing substitute for CH. Compared to CH, they induced more positive pulpal reactions.

Evaluation of the reasons for failure in teeth with vital amputation treatment

AIM

This study aims to evaluate the primary teeth undergoing amputation due to dental caries or trauma clinically and radiologically.

MATERIAL AND METHODS

The amputation treatment of 90 primary teeth of 58 patients (Female: 20, Male: 38) aged 4-11 years was evaluated clinically and radiologically. Calcium Hydroxide was used for amputation in this study. Composite or amalgam was preferred as filling material in the same session of the patients. Clinical/radiological (Periapical/Panoramic X-ray) examination was performed on the teeth that were unsuccessful in treatment, on the day of the patient's complaint, and at the end of 1 year in the others.

RESULTS

According to the clinical and radiological findings of the patients, 14.4% of the boys and 12.3% of the girls were unsuccessful. Amputation in male was a need in the 6-7 age group with a rate of 44.6% at most. Amputation in females was a need in the 8-9 age group with a rate of 52% at most.

CONCLUSION

Success in amputation treatment depends on the tooth, the dentist, and the dental material applied.

Pulp therapy and root canal treatment techniques in immature permanent teeth: an update

Background According to the Children's Dental Health Survey 2013, around one in ten children in Wales, Northern Ireland and England will have sustained dental trauma to a permanent incisor by the of age 15. Management of an exposed pulp in an immature permanent incisor is often urgent and has an impact on the long-term outcome of the tooth; therefore, it is essential that general dental practitioners feel confident in managing such a scenario to achieve an optimal outcome. This paper discusses the indications, technique, materials and outcomes.Aims This article aims to review the literature, which discusses various treatment modalities and materials for pulpal therapy and root canal treatment in the immature permanent tooth.Method Electronic searches were limited to English language, human studies, published within the past five years and the medical subject heading terms used were: direct pulp capping, apexogenesis, Cvek pulpotomy, full pulpotomy/pulpectomy, partial pulpotomy, apexification, non-vital pulp therapy and mineral trioxide aggregate apexification. Older, seminal articles identified through the references sections have also been included.Conclusion A number of options are available for the management of immature permanent teeth that have suffered an insult such as caries or trauma. This paper reviews the various methods of pulpal treatment, preservation therapy and root canal treatment options depending on the extent of the damage.

Periodontal Tissue Reaction Consecutive Implantation of Endodontic Materials and Subsequent Integration of Complex Oral Rehabilitation Treatments

Oral rehabilitation is a main branch of dentistry focused on diagnosing the patient’s problem and creating a treatment plan to restore aesthetics, recondition morphologically all components, and recover the functionality of the oral cavity. Biological compatibility of the materials used has a major importance, due to the direct contact with essential tissues, such as the soft and hard tissue of the periodontium and the potential influence on the outcome of the treatment. The present material aims to assess the inflammatory response after subcutaneous implantation of three materials frequently used in endodontics (Mineral Trioxide Aggregate—MTA, DiaRoot BioAggregate, and Sealapex). The evaluation of the reparative tissue reaction after 7, 30, and 60 days, respectively, subsequent to in vivo implantation, was carried out through electron microscopy imaging. Moreover, evaluation of the dynamics of the osteogenesis process was an indicator for the maintenance of internal homeostasis in the context of complex intraoral rehabilitation treatments that include fixed prosthodontics correlated with the particular periodontal-aesthetic aspects and completed by cranio-mandibular repositioning. Our study showed increased absolute values of alkaline phosphatase in all material-implanted cases (more pronounced in MTA and Bio Aggregate), highlighting that this enzyme could be an effective indicator of bone formation, which takes place after the material implantation, with the most significant elevated values at 30 days postoperatively.

Biological evaluation of hesperidin for direct pulp capping in dogs' teeth

This study compared the biological effect of Hesperidin, Mineral Trioxide Aggregate (MTA)-Angelus and calcium hydroxide for direct pulp capping. A total of 126 dogs, teeth were divided according to the post-treatment evaluation period into three groups (42 teeth each), group I: 2 weeks, group II: 4 weeks and group III: 8 weeks. Each group was further subdivided according to the pulp capping material into three subgroups (14 teeth each), subgroup A (Hesperidin), subgroup B (MTA-Angelus) and subgroup C (Dycal). Both inflammatory response and dentine bridge formation were assessed by histopathology. All data were statistically analysed. Resolution of the inflammation was recorded by the time with a significant difference between subgroups   within the same group (P<.05). Hesperidin, MTA-Angelus and Dycal showed either mild or moderate inflammation at 2 weeks with significant differences between subgroups (P < .05). At 4 and 8 weeks, there were no significant differences between subgroups (P > .05). Absence of complete or partial calcified bridge with no odontoblastic layer was reported in all subgroups at 2 weeks while at 4 weeks, the majority of samples in Hesperidin and MTA subgroups showed amorphous calcified deposit. At 8 weeks, there was no significant difference (P > .05) between subgroups except that 78.5% and 92.9% of Hesperidin and MTA-Angelus samples, respectively, showed moderate dentine bridge. Also, 78.5% of Hesperidin and Dycal samples revealed moderately thick dentine bridge while 78.7% of MTA-Angelus showed a thin dentine bridge with a significant difference between them (P < .05). In conclusion, Hesperidin is a promising pulp capping material inducing mild inflammation and good dentine bridge formation.

EDTA Promotes the Mineralization of Dental Pulp In Vitro and In Vivo

INTRODUCTION

Dentin regeneration is one of the main goals of vital pulp treatment in which the biological properties of dental pulp cells (DPCs) need to be considered. In our previous study, we showed that EDTA could enhance the stromal cell-derived factor 1 alpha-induced migration of DPCs. The purpose of this study was to explore the effects of EDTA on the mineralization of dental pulp in vitro and in vivo.

METHODS

DPCs were obtained from human premolars or third molars. Alkaline phosphatase assays and alizarin red S staining were used to examine the degree of differentiation and mineralized nodule formation of DPCs. Real-time polymerase chain reaction and Western blot analysis were performed to detect the messenger RNA and protein expressions of mineralization-related markers in DPCs. Extracellular-regulated protein kinase and Smad inhibitors were used to study the roles of these 2 signaling pathways in this process. In addition, pulp exposures were created on 18 premolars of 2 beagle dogs (>12 months) using a high-speed dental handpiece. The experimental group (n = 9) was treated with 12% EDTA for 5 minutes, and the control group (n = 9) was treated with sterile saline for the same duration. Mineral trioxide aggregate was used for direct pulp capping followed by glass ionomer cement sealing. Samples were collected 3 months later, and the regenerated dentin was assessed by micro-computed tomographic and histologic analyses.

RESULTS

Exposure to 12% EDTA promoted the activity of alkaline phosphatase, the formation of mineralized nodules, and the messenger RNA and protein expressions of mineralization-related markers in DPCs. Furthermore, the process of 12% EDTA enhancing the differentiation of DPCs was mediated by the extracellular-regulated protein kinase 1/2 signaling pathway and inhibited by the Smad2/3 signaling pathway. In vivo, compared with the control group, more regenerated dentin that had fewer tunnel defects was formed in the 12% EDTA-treated group.

CONCLUSIONS

Our results showed that 12% EDTA could promote the mineralization of dental pulp in vitro and in vivo.

Partial Pulpotomy with Mineral Trioxide Aggregate in Permanent Incisors with Complicated Crown Fracture: 5-Year Follow-Up

Traumatic dental injuries are highly prevalent among children. This article describes a case report of a patient who has experienced dental trauma at 8 years old, which has led to enamel-dentine fracture with pulp exposure in the left central incisor and crown-root fracture with pulp exposure in the right central incisor. Partial pulpotomy was performed with the aim of maintaining the neurovascular bundle, thus allowing normal radicular formation. During follow-up 5 years later, teeth were asymptomatic and with no evidence of radiolucent lesions in radiographic examinations. This report demonstrates that traumatic fractures with pulp exposure can be treated effectively by the described technique.

The effect of dental pulp-capping materials on hard-tissue barrier formation: A systematic review and meta-analysis

BACKGROUND

The authors of this systematic review aimed to compare the effects of pulp-capping materials on hard-tissue barrier formation using histologic assessments.

TYPE OF STUDIES REVIEWED

The authors included randomized controlled trials and controlled clinical trials in humans, with vital therapies performed on healthy permanent teeth undergoing experimental mechanical pulp exposures. They searched electronically in the PubMed, Cochrane, Embase, and Summon databases and carried out a manual search. Twenty-seven full-text articles were eligible for inclusion in the systematic review. After data extraction, the authors performed 2 sets of meta-analyses with odds ratios (OR) and their 95% confidence intervals (CI) on 22 studies. Ten studies compared mineral trioxide aggregate (MTA) with calcium hydroxide (CH), and 12 compared bonding agents with CH. The authors assessed bias by means of Cochrane Collaboration's tool for assessing risk, funnel plots, and Harbord test.

RESULTS

The use of MTA was associated with a higher rate of hard-tissue barrier formation than CH. The OR comparing the 2 groups was 2.45 (95% CI, 1.39 to 4.29; P = .002). Use of bonding agents was associated with a lower rate of hard-tissue barrier formation than CH. The OR comparing the 2 groups was 0.02 (95% CI, 0.01 to 0.05; P < .001).

CONCLUSIONS AND PRACTICAL IMPLICATIONS

The results suggest that MTA and CH have positive effects on hard-tissue barrier formation. On the basis of the evidence, the authors conclude that MTA has better effects than CH regarding dental pulp protection in the capping of mechanical pulp exposures. Conversely, bonding agents are inferior to CH.

Effects of pulpotomy using mineral trioxide aggregate on prostaglandin transporter and receptors in rat molars

Mineral trioxide aggregate (MTA) is a commonly used dental pulp-capping material with known effects in promoting reparative dentinogenesis. However, the mechanism by which MTA induces dentine repair remains unclear. The aim of the present study was to investigate the role of prostaglandin E₂ (PGE₂) in dentine repair by examining the localisation and mRNA expression levels of its transporter (Pgt) and two of its receptors (Ep2 and Ep4) in a rat model of pulpotomy with MTA capping. Ep2 expression was detected in odontoblasts, endothelial cells, and nerve fibres in normal and pulpotomised tissues, whereas Pgt and Ep4 were immunolocalised only in the odontoblasts. Moreover, mRNA expression of Slco2a1 (encoding Pgt), Ptger2 (encoding Ep2), and Ptger4 (encoding Ep4) was significantly upregulated in pulpotomised dental pulp and trigeminal ganglia after MTA capping. Our results provide insights into the functions of PGE₂ via Pgt and Ep receptors in the healing dentine/pulp complex and may be helpful in developing new therapeutic targets for dental disease.

Healing response of rat pulp treated with an injectable keratin hydrogel

Background

Keratin has shown promising outcomes as a biomaterial due to its inherent bioactivity, biocompatibility and regenerative effects. The effect of keratin on repair and regeneration of dental tissues has never been studied before. Current therapies to treat pulp tissues involve its replacement with inert, synthetic materials that do not have a proper biological function, leading to failure and tooth loss. This study aimed to develop a biocompatible keratin hydrogel (KH) suitable for pulp therapies.

Methods

Keratins extracted from sheep wool were isolated, quantified and reconstituted to form KH. Different concentrations of keratin gel suitable for dental application were characterized by rheological analysis. The optimized gel based on flow characteristics was studied further for microstructure including porosity, percentage swelling ratio and contact angle measurements, using analytical tools such as scanning electron microscopy (SEM), micro-computed tomography and goniometer. To assess both biocompatibility and pulpal response, KH was implanted into rat upper molar teeth following partial pulpotomy. After 28 days, the tissue sections were analyzed by histological and immunohistochemical methods to identify dentin matrix protein 1 (DMP-1) formation and compared with control (Ca(OH)₂-treated) teeth.

Results

The results of the study demonstrated a viscous and injectable, porous, dimensionally stable, hydrophilic and biocompatible gel that allowed pulp healing to occur by a reparative response, with widespread DMP-1 expression.

Conclusions

The findings of this study indicate that keratins can be developed as a biomaterial source for alternate biological treatment options for pulp therapies.

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.

Analysis of organic components in resin-modified pulp capping materials: critical considerations

The purpose of this study was to elucidate the organic composition and eluates of three resin-based pulp-capping materials in relation to their indications and safety data sheets. Uncured samples of Theracal LC, Ultra-Blend Plus, and Calcimol LC were investigated using gas chromatography-mass spectrometry (GC-MS) and ultra-performance liquid chromatography-mass spectrometry (UPLC-MS). Identification/quantification of 7-d leachables of cured samples was performed using GC-MS for 2-hydroxyethyl methacrylate (HEMA), 2-(dimethylamino)ethyl methacrylate (DMAEMA), camphorquinone (CQ), ethylene glycol dimethacrylate (EGDMA), ethyl-4-(dimethylamino)benzoate (DMABEE), and triethylene glycol dimethacrylate (TEGDMA). A similar organic composition was found for Ultra-Blend and Calcimol; however, only Ultra-Blend is indicated for direct pulp-capping. In contrast to the other materials analysed, Theracal contained substances of high molecular weight. The safety data sheets of all materials were incomplete. We detected HEMA, CQ, and TEGDMA in eluates from Ultra-Blend and Calcimol, and it was considered that HEMA might have originated from decomposition of diurethane dimethacrylate (UDMA) in the GC-injector. For Theracal, additives associated with light curing (DMABEE and CQ) were detected in higher amounts (4.11 and 19.95 μg mm^-2 ) than in the other materials. Pores were quantified in all samples by micro-computed tomography (micro-CT) analysis, which could influence leaching. The organic substances in the investigated materials might affect their clinical suitability as capping agents, especially for direct capping procedures.

Effect of an Experimental Direct Pulp-capping Material on the Properties and Osteogenic Differentiation of Human Dental Pulp Stem Cells

Effective pulp-capping materials must have antibacterial properties and induce dentin bridge formation; however, many current materials do not satisfy clinical requirements. Accordingly, the effects of an experiment pulp-capping material (Exp) composed of an antibacterial resin monomer (MAE-DB) and Portland cement (PC) on the viability, adhesion, migration, and differentiation of human dental pulp stem cells (hDPSCs) were examined. Based on a Cell Counting Kit-8 assay, hDPSCs exposed to Exp extracts showed limited viability at 24 and 48 h, but displayed comparable viability to the control at 72 h. hDPSC treatment with Exp extracts enhanced cellular adhesion and migration according to in vitro scratch wound healing and Transwell migration assays. Exp significantly upregulated the expression of osteogenesis-related genes. The hDPSCs cultured with Exp exhibited higher ALP activity and calcium deposition in vitro compared with the control group. The novel material showed comparable cytocompatibility to control cells and promoted the adhesion, migration, and osteogenic differentiation of hDPSCs, indicating excellent biocompatibility. This new direct pulp-capping material containing MAE-DB and PC shows promise as a potential alternative to conventional materials for direct pulp capping.

Success Rate of MTA Pulpotomy on Vital Pulp of Primary Molars: A 3-Year Observational Study

Introduction

Vital pulp therapy is a major contributor in the preservation of primary dentition after caries affliction. Introduction of mineral trioxide aggregate (MTA) has revolutionized such treatment.

Aim

The aim of our study was to evaluate and correlate the effects of MTA clinically and radiographically on pulpotomized primary molars till their exfoliation or extraction followed by histological evaluation.

Study design

This is an observational study.

Materials and methods

A total of 25 teeth were selected from 5- to 8-year-old children requiring pulp therapy on the basis of inclusion and exclusion criterion. The teeth were treated by conventional pulpotomy technique under aseptic conditions using MTA and were immediately restored with stainless steel crown. The teeth were assessed postoperatively till 36 months. The exfoliated or extracted teeth were examined histologically.

Results

The pulpotomized teeth were vital with no adverse clinical findings during the observation period. After 3 months, one tooth showed internal resorption, but the same was not observed after 12 months. Pulp canal obliteration was seen in three cases. At the end of the study, five teeth were exfoliated and one tooth was extracted for maintaining arch symmetry. The histological examination of extracted tooth revealed the presence of healthy pulp and the area of true calcification. Remaining exfoliated teeth presented dentin bridge formation.

Statistics

Frequencies and percentages were used for descriptive statistics. Fisher’s exact tests were used to see the difference between clinical and radiological findings. The probability value was fixed at 5% level of significance.

Conclusion

The response of pulp in primary teeth to MTA was favorable in all cases from clinical and radiographic perspective, and histological evaluation confirmed the observation.

How to cite this article

Godhi B, Tyagi R. Success Rate of MTA Pulpotomy on Vital Pulp of Primary Molars: A 3-Year Observational Study. Int J Clin Pediatr Dent 2016;9(3):222-227.

The use of lasers for direct pulp capping

Direct pulp capping helps extend the life of a diseased tooth by maintaining tooth vitality. Nowadays, lasers are more frequently used during direct pulp capping in the clinic, but their use has not been previously reviewed. This review presents the basic properties of currently available lasers, scientific evidence on the effects of laser application on direct pulp capping, and future directions for this technology. An extensive literature search was conducted in various databases for articles published up to January 2015. Original in vitro, in vivo, and clinical studies, reviews, and book chapters published in English were included. Various laser systems have been increasingly and successfully applied in direct pulp capping. Lasers offer excellent characteristics in terms of hemostasis and decontamination for field preparation during direct pulp capping treatment; however, the sealing of exposed pulp with one of the dental materials, such as calcium hydroxide, mineral trioxide aggregates, and bonded composite resins, is still required after laser treatment. Clinicians should consider the characteristics of each wavelength, the emission mode, irradiation exposure time, power, type of laser tip, and the distance between the laser tip and the surface being irradiated.

Management of mucosal fenestration with external root resorption by multidisciplinary approach

Mucosal fenestration is a clinical condition in which the overlying gingiva is denuded and the root is exposed to the oral cavity. Invasive cervical resorption is an entirely uncommon entity and its aetiology is poorly understood. This case presents an invasive cervical resorption of maxillary right central incisor with fenestration at the cervical third of the tooth. The resorption area was chemomechanically debrided. It was then restored with Mineral Trioxide Aggregate over which pink glass ionomer cement (GC Fuji VII) was placed. Lateral pedicle flap was used to cover the fenestration. The resorptive defect was restored using tooth coloured restorative resin after removal of the pink glass ionomer cement. Orthodontic treatment was continued for correction of malocclusion.

External cervical resorption case report and a brief review of literature

External cervical resorption (ECR) is the loss of dental hard tissue as a result of odontoclastic action; it usually begins on the cervical region of the root surface of the teeth. The etiology, predisposing factors, diagnosis, and management of ECR have been reviewed here. Effective management and appropriate treatment can only be carried out if the true nature and exact location of the ECR lesion are known. This paper reports on the management of a case of external cervical root resorption (ECRR), which involved root canal treatment and removal of the resorbing area of the affected tooth as well as filling the resorbed area with mineral trioxide aggregate (MTA) and resin-modified glass ionomer filling material (RMGIC). The defect was filled with bone graft material and guided tissue regeneration (GTR) membrane. This case highlights the importance of using MTA and successful management of cervical resorption with a stable uneventful clinical recovery.

Comparison of CaOH with MTA for direct pulp capping: a PBRN randomized clinical trial

This practice-based, randomized clinical trial evaluated and compared the success of direct pulp capping in permanent teeth with MTA (mineral trioxide aggregate) or CaOH (calcium hydroxide). Thirty-five practices in Northwest PRECEDENT were randomized to perform direct pulp caps with either CaOH (16 practices) or MTA (19 practices). Three hundred seventy-six individuals received a direct pulp cap with CaOH (n = 181) or MTA (n = 195). They were followed for up to 2 yrs at regular recall appointments, or as dictated by tooth symptoms. The primary outcomes were the need for extraction or root canal therapy. Teeth were also evaluated for pulp vitality, and radiographs were taken at the dentist's discretion. The probability of failure at 24 mos was 31.5% for CaOH vs. 19.7% for MTA (permutation log-rank test, p = .046). This large randomized clinical trial provided confirmatory evidence for a superior performance with MTA as a direct pulp-capping agent as compared with CaOH when evaluated in a practice-based research network for up to 2 yrs.

Calcium Hydroxide vs. Mineral Trioxide Aggregates for Partial Pulpotomy of Permanent Molars with Deep Caries

AIM

To prospectively compare the clinical success rate of partial pulpotomy treatment in permanent molars using calcium hydroxide (CH) and mineral trioxide aggregates (MTA) as pulp dressing agents.

METHODS

Restorable permanent first molars (64) with carious pulp exposures were randomly assigned to two groups; CH and MTA. A standardized operative procedure was followed in both groups. Following isolation and caries removal, the exposed superficial pulp tissue layers were removed with a sterile flame shape diamond bur to a depth of 2-4 mm. Bleeding was controlled and pulp dressed with either a paste of non-setting Ca(OH)2 followed by a setting layer of Ca(OH)2, or with grey MTA. The dressing materials in both groups were then covered with a layer of light cured glass ionomer cement. The teeth were either restored using amalgam, or where grossly carious with preformed metal crowns. Patients were scheduled for follow-up at 3, 6, 12 months and annually thereafter.

RESULTS

There were 34 patients (17 males and 17 females) with 51 teeth available for evaluation. The age of patients at the time of restoration ranged between 6.8 to 13.3 years (mean of 10.3 +/- 1.8 years). The follow-up period ranged from 25.4 to 45.6 months with an average of 34.8 +/- 4.4 months. There was no statistically significant difference in the success rate of teeth treated with CH (91%) in comparison to teeth treated with MTA (93%). Radiographically, a hard tissue barrier under CH was noticed in 12 (55%) teeth compared with 18 (64%) teeth under MTA (p=0.4).

CONCLUSIONS

MTA has clinical success rate comparable to CH as a pulp dressing material for partial pulpotomy in permanent molars with carious exposures.

Evaluation of mineral trioxide aggregate (MTA) versus calcium hydroxide cement (Dycal(®) ) in the formation of a dentine bridge: a randomised controlled trial

AIM

To assess the effectiveness of mineral trioxide aggregate (MTA) used as an indirect pulp-capping material in human molar and premolar teeth.

METHODOLOGY

We conducted a clinical evaluation of 60 teeth, which underwent an indirect pulp-capping procedure with either MTA or calcium hydroxide cement (Dycal(®) ). Calcium hydroxide was compared with MTA and the thickness of the newly formed dentine was measured at regular time intervals. The follow-up was at 3 and 6 months, and dentine formation was monitored by radiological measurements on digitised images using Mesurim Pro(®) software.

RESULTS

At 3 months, the clinical success rates of MTA and calcium hydroxide were 93% and 73%, respectively (P = 0.02). At 6 months, the success rate was 89.6% with MTA, and remained steady at 73% with calcium hydroxide (P = 0.63). The mean initial residual dentine thickness was 0.23 mm, and increased by 0.121 mm with MTA and by 0.136 mm with calcium hydroxide at 3 months. At 6 months, there was an increase of 0.235 mm with MTA and of 0.221 mm with calcium hydroxide.

CONCLUSIONS

  A higher success rate was observed in the MTA group relative to the Dycal(®) group after 3 months, which was statistically significant. After 6 months, no statistically significant difference was found in the dentine thickness between the two groups. Additional histological investigations are needed to support these findings.

A Histopathological Comparison of Pulpal Response to Chitra-CPC and Formocresol used as Pulpotomy Agents in Primary Teeth: A Clinical Trial

Preventive measures have helped to minimize the occurrence of dental caries. However, premature loss of primary teeth on account of dental caries still remains a common problem among children. The pulpotomy technique has been the choice for treating vital primary and young permanent teeth with carious, mechanical and traumatic pulp exposures. The ideal pulpotomy medicament should be bioinductive or at least biocompatible, bactericidal and harmless to the pulp and surrounding structures. It should also promote healing of the radicular pulp and prevent bacterial microleakage with the least interference in the physiological process of root resorption. Since the best criteria for judging the effectiveness of a medicament when used for vital pulp therapy is the response that it produces in the pulp. The purpose of the present study was to evaluate and compare the response of human pulp tissue to recently developed Indian material, Sree Chitra-Calcium Phosphate Cement (Chitra-CPC) and formocresol, used as pulpotomy agent in deciduous teeth. Chitra-CPC has been compared with formocresol, taking into account that formocresol is still considered the gold standard in primary tooth pulpotomy. The study was conducted among 10 children in the age group of 8 to 12 years focusing on 20 noncarious primary canines indicated for serial extraction. Each patient received two different pulpotomy procedures—one in each of the primary canines using formocresol and the other with Chitra-CPC as pulpotomy agents. After 70 days, the teeth were extracted and subjected to histological examination. The results did not reveal statistically significant difference between the two groups. But Chitra-CPC gave more favorable results, in respect of pulpal inflammation, dentin bridge formation, quality of dentin bridge and connective tissue in dentin bridge.

How to cite this article: Ratnakumari N, Thomas B. A Histopathological Comparison of Pulpal Response to Chitra- CPC and Formocresol used as Pulpotomy Agents in Primary Teeth: A Clinical Trial. Int J Clin Pediatr Dent 2012;5(1):6-13.

Mineral trioxide aggregate or calcium hydroxide direct pulp capping: an analysis of the clinical treatment outcome

INTRODUCTION

The use of mineral trioxide aggregate (MTA) might improve the prognosis of teeth after pulp exposure. The treatment outcome of teeth after direct pulp capping, either with mineral trioxide aggregate (MTA) or calcium hydroxide (controls), was investigated, taking into account possible confounding factors.

METHODS

One hundred forty-nine patients treated between 2001 and 2006 who received direct pulp capping treatment in 167 teeth met the inclusion criteria. Treatment was performed by supervised undergraduate students (72%) and dentists (28%). Assessment of clinical and radiographic outcomes was performed by calibrated examiners 12-80 months after treatment (median, 27 months).

RESULTS

One hundred eight patients (122 treated teeth) were available for follow-up (72.5% recall rate). A successful outcome was recorded for 78% of teeth (54 of 69) in the MTA group and for 60% of teeth (32 of 53) in the the calcium hydroxide group. The univariate analysis (generalized estimation equations model [GEE model] showed a significant difference in the success rate (odds ratio [OR], 2.36; 95% confidence interval [CI], 1.05-5.32; P = .04). In the multiple analysis (GEE model), the OR is marginally inside the nonsignificant range (OR, 0.43; 95% CI, 0.19-1.02; P = .05) when conspicuous confounding factors are stabilized (univariate analysis). Multiple analysis showed that teeth that were permanently restored >or=2 days after capping had a significantly worse prognosis in both groups (OR, 0.24; 95% CI, 0.09-0.66; P = .01).

CONCLUSIONS

MTA appears to be more effective than calcium hydroxide for maintaining long-term pulp vitality after direct pulp capping. The immediate and definitive restoration of teeth after direct pulp capping should always be aimed for.

Histology of Irreversible Pulpitis Premolars Treated with Mineral Trioxide Aggregate Pulpotomy

When caries and bacterial contamination can be mostly eliminated from the dentin-pulp complex, the inflamed pulp of a human permanent tooth with irreversible pulpitis may have a chance to return to a healthy and functional status after mineral trioxide aggregate pulpotomy.

Cytotoxicity and biocompatibility of direct and indirect pulp capping materials

There are several studies about the cytotoxic effects of dental materials in contact with the pulp tissue, such as calcium hydroxide (CH), adhesive systems, resin composite and glass ionomer cements. The aim of this review article was to summarize and discuss the cytotoxicity and biocompatibility of materials used for protection of the dentin-pulp complex, some components of resin composites and adhesive systems when placed in direct or indirect contact with the pulp tissue. A large number of dental materials present cytotoxic effects when applied close or directly to the pulp, and the only material that seems to stimulate early pulp repair and dentin hard tissue barrier formation is CH.

Cytotoxic effects of White-MTA and MTA-Bio cements on odontoblast-like cells (MDPC-23)

This study evaluated the cytotoxic effects of 2 mineral trioxide aggregate (MTA) cements - White-MTA-Angelus and a new formulation, MTA-Bio - on odontoblast-like cell (MDPC-23) cultures. Twenty-four disc-shaped (2 mm diameter x 2 mm thick) specimens were fabricated from each material and immersed individually in wells containing 1 mL of DMEM culture medium for either 24 h or 7 days to obtain extracts, giving rise to 4 groups of 12 specimens each: G1 - White-MTA/24 h; G2 - White-MTA/7 days; G3 - MTA-Bio/24 h; and G4 - MTA-Bio/7 days. Plain culture medium (DMEM) was used as a negative control (G5). Cells at 30,000 cells/cm² concentration were seeded in the wells of 24-well plates and incubated in a humidified incubator with 5% CO2 and 95% air at 37ºC for 72 h. After this period, the culture medium of each well was replaced by 1 mL of extract (or plain DMEM in the control group) and the cells were incubated for additional 2 h. Cell metabolism was evaluated by the MTT assay and the data were analyzed statistically by ANOVA and Tukey's test (α=0.05). Cell morphology and the surface of representative MTA specimens of each group were examined by scanning electron microscopy. There was no statistically significant difference (p>0.05) between G1 and G2 or between G3 and G4. No significant difference (p>0.05) was found between the experimental and control groups either. Similar cell organization and morphology were observed in all groups, regardless of the storage periods. However, the number of cells observed in the experimental groups decreased compared to the control group. MTA-Bio presented irregular surface with more porosities than White-MTA. In conclusion, White-MTA and MTA-Bio presented low cytotoxic effects on odontoblast-like cell (MDPC-23) cultures.

Pulp Capping with Mineral Trioxide Aggregate (MTA): A Retrospective Analysis of Carious Pulp Exposures Treated by Undergraduate Dental Students

Carious pulp exposures present a therapeutic challenge for clinicians. Mineral trioxide aggregate (MTA) is a treatment option that may provide successful outcomes for the capping of carious pulp exposures in adult patients. However, the success measured as pulp survival over a period of one and two years of pulp caps performed by undergraduate dental students may be low. This study provides data regarding the impact of exposure sizes and other pre-operative variables on outcomes of MTA pulp caps in adults.

Reparative dentinogenesis induced by mineral trioxide aggregate: a review from the biological and physicochemical points of view

This paper aims to review the biological and physicochemical properties of mineral trioxide aggregate (MTA) with respect to its ability to induce reparative dentinogenesis, which involves complex cellular and molecular events leading to hard-tissue repair by newly differentiated odontoblast-like cells. Compared with that of calcium hydroxide-based materials, MTA is more efficient at inducing reparative dentinogenesis in vivo. The available literature suggests that the action of MTA is attributable to the natural wound healing process of exposed pulps, although MTA can stimulate hard-tissue-forming cells to induce matrix formation and mineralization in vitro. Physicochemical analyses have revealed that MTA not only acts as a "calcium hydroxide-releasing" material, but also interacts with phosphate-containing fluids to form apatite precipitates. MTA also shows better sealing ability and structural stability, but less potent antimicrobial activity compared with that of calcium hydroxide. The clinical outcome of direct pulp capping and pulpotomy with MTA appears quite favorable, although the number of controled prospective studies is still limited. Attempts are being conducted to improve the properties of MTA by the addition of setting accelerators and the development of new calcium silicate-based materials.

Carbon dioxide laser irradiation stimulates mineralization in rat dental pulp cells

AIM

To examine the effect of carbon dioxide laser irradiation on mineralization in dental pulp cells.

METHODOLOGY

Rat dental pulp cells were irradiated with a carbon dioxide laser at 2 W output power for 20, 40 and 60 s, and were cultured in ascorbic acid and beta-glycerophosphate containing media. Cell viability was examined 24 h after laser irradiation by a modified MTT assay. Alizarin Red S staining was performed 10 days after laser irradiation. The amounts of secreted collagen from the cells after irradiation were quantified following Sirius Red staining. The expression levels of collagen type I and HSP47, collagen-binding stress protein, were analysed by real-time PCR. HSP47 protein expression was examined by Western blotting. Statistical analysis was performed using one-way analysis of variance (anova) followed by the Tukey's multiple comparison test.

RESULTS

The cell viability was not affected by laser irradiation at 2 W for up to 40 s. However, it was significantly decreased by 20% at 60 s (P < 0.05). The amount of mineralization after 10 days of irradiation at 2 W for 40 s was significantly increased in comparison to the other conditions (P < 0.05). The extracellular collagen production was significantly increased by 73% on day 2 and 38% on day 4 after laser irradiation (P < 0.05). Although collagen type I gene expression was not changed by laser irradiation, HSP47 gene and protein expression was induced within 12 and 24 h, respectively.

CONCLUSIONS

These results suggested that carbon dioxide laser irradiation stimulated mineralization in dental pulp cells. The laser irradiation also increased HSP47 expression but not collagen gene expression.