Repair of furcal perforation using a new endodontic cement

A Review of the research methods and progress of biocompatibility evaluation of root canal sealers

The function of root canal sealer was to achieve an appropriate three-dimensional filling effect by filling the root canal and some irregular lumen, thereby inhibiting the residual bacteria. There were many types of sealers, but research to find the most suitable ones was still ongoing. In recent years, researchers had continuously improved the performance of sealers by developing new sealers or adding active ingredients to the sealers. However, most sealers exhibit varying degrees of cytotoxicity and tissue responses, which affect clinical therapy efficacy. This review describes different technical approaches, and recent research progress in the biocompatibility evaluation of root canal sealers and provides brief insights into this field by summarising the performance studies of different root canal sealers.

The Effects of Tricalcium-Silicate-Nanoparticle-Containing Cement: In Vitro and In Vivo Studies

A tricalcium-silicate-nanoparticle-containing cement (Biodentine) was developed to overcome the disadvantages of existing mineral trioxide aggregate (MTA) dental materials. This study aimed at evaluating the effects of Biodentine on the osteogenic differentiation of human periodontal ligament fibroblasts (HPLFs) in vitro and the healing of furcal perforations created experimentally in rat molars in vivo, in comparison to MTA. The in vitro studies performed the following assays: pH measurement using a pH meter, the release of calcium ions using a calcium assay kit, cell attachment and morphology using SEM, cell proliferation using a coulter counter, marker expression using quantitative reverse transcription polymerase chain reaction (qRT-PCR) and cell mineralized deposit formation using Alizarin Red S (ARS) staining. In the in vivo studies, MTA and Biodentine were used to fill the rat molar perforations. Rat molars were processed at 7, 14 and 28 days for analysis of inflammatory processes using hematoxylin and eosin (HE) staining, immunohistochemical staining of Runx2 and tartrate-resistant acid phosphate (TRAP) staining. The results demonstrate that the nanoparticle size distribution of Biodentine is critical for osteogenic potential at an earlier stage compared to MTA. Further studies are required to elucidate the mechanism of action of Biodentine in osteogenic differentiation.

Chitosan-Based Accelerated Portland Cement Promotes Dentinogenic/Osteogenic Differentiation and Mineralization Activity of SHED

Calcium silicate-based cements (CSCs) are widely used in various endodontic treatments to promote wound healing and hard tissue formation. Chitosan-based accelerated Portland cement (APC-CT) is a promising and affordable material for endodontic use. This study investigated the effect of APC-CT on apoptosis, cell attachment, dentinogenic/osteogenic differentiation and mineralization activity of stem cells from human exfoliated deciduous teeth (SHED). APC-CT was prepared with various concentrations of chitosan (CT) solution (0%, 0.625%, 1.25% and 2.5% (w/v)). Cell attachment was determined by direct contact analysis using field emission scanning electron microscopy (FESEM); while the material extracts were used for the analyses of apoptosis by flow cytometry, dentinogenic/osteogenic marker expression by real-time PCR and mineralization activity by Alizarin Red and Von Kossa staining. The cells effectively attached to the surfaces of APC and APC-CT, acquiring flattened elongated and rounded-shape morphology. Treatment of SHED with APC and APC-CT extracts showed no apoptotic effect. APC-CT induced upregulation of DSPP, MEPE, DMP-1, OPN, OCN, OPG and RANKL expression levels in SHED after 14 days, whereas RUNX2, ALP and COL1A1 expression levels were downregulated. Mineralization assays showed a progressive increase in the formation of calcium deposits in cells with material containing higher CT concentration and with incubation time. In conclusion, APC-CT is nontoxic and promotes dentinogenic/osteogenic differentiation and mineralization activity of SHED, indicating its regenerative potential as a promising substitute for the commercially available CSCs to induce dentin/bone regeneration.

Does MTA provide a more favourable histological response than other materials in the repair of furcal perforations? A systematic review

BACKGROUND

There is no consensus on which furcal perforation repair material induces a more favourable histological response. This systematic review of laboratory studies provides an overview of the studies comparing repair materials in animal models.

OBJECTIVES

To evaluate whether mineral trioxide aggregate (MTA) yields a more favourable histological response than other materials when used to repair furcal perforations in animal experimental models.

METHODS

This review followed the PRISMA checklist. The studies included various materials used to repair furcal perforations and compared the histological responses with MTA. An electronic search was conducted in EMBASE, PubMed, Scopus and Web of Science up to 2 September 2020, with no language or publication date restrictions. Studies whose full text was unavailable were excluded. The ARRIVE and SYRCLE tools were used to assess the methodological quality and risk of bias (RoB) of the studies.

RESULTS

The studies included in the qualitative synthesis were conducted in rat (n = 3) and dog (n = 17) models. They were classified as having a low quality, high methodological heterogeneity and high RoB. MTA and Biodentine, the materials most often compared, reduced the inflammatory reaction to mild over time. In addition, a mineralized tissue was formed in all studies. The response yielded by MTA was better than or equivalent to that of the other tested materials.

DISCUSSION

This review confirmed that MTA is the reference standard material for furcal perforation repair. However, research using animal models has inherent limitations, and the substantial methodological heterogeneity across the studies included should be considered. Therefore, the knowledge generated by this systematic review should be translated into clinical practice cautiously.

CONCLUSIONS

Features described in the report and quality assessment guidelines, such as PRIASE, ARRIVE and SYRCLE, should guide researchers. Despite the high RoB and the low methodological quality of the studies included, findings indicated that MTA yields a more favourable histological response than other materials in the repair of furcal perforations.

REGISTRATION

PROSPERO (CRD42020181297).

In vivo Biocompatibility and Bioactivity of Calcium Silicate-Based Bioceramics in Endodontics

Endodontic therapy aims to preserve or repair the activity and function of pulp and periapical tissues. Due to their excellent biological features, a substantial number of calcium silicate-based bioceramics have been introduced into endodontics and simultaneously increased the success rate of endodontic treatment. The present manuscript describes the in vivo biocompatibility and bioactivity of four types of calcium silicate-based bioceramics in endodontics.

Outcomes of direct pulp capping in vital primary teeth with cariously and non-cariously exposed pulp: A systematic review

OBJECTIVE

To summarize the clinical/radiographic outcomes from the evidence of studies published since 1988 on different DPC agents applied on vital pulp-exposed primary teeth.

METHODS

The following electronic databases were searched: PubMed, Embase, Cochrane Library, Dentistry and Oral Science Source, and Google Scholar. Inclusion criteria were randomized controlled trials (RCTs) published between January 1988 and December 2019, with at least 6 months of follow-up, comparing the clinical and radiographic success rates of two or more DPC agents applied in primary teeth with cariously and non-cariously exposed pulp.

RESULTS

Initial searches identified 83 potentially relevant studies on DPC in primary teeth. Sixty-four of these studies were excluded, whereas 19 articles satisfied the inclusion criteria and were retrieved in full text for data extraction and a methodological quality assessment. Finally, 12 of these articles were included in the systematic review. Low and moderate risks of bias were observed. Overall, DPC clinical and radiographic success rates among the selected studies ranged between 53% and 100%.

CONCLUSIONS

For DPC in primary teeth, this systematic review found that diverse new biologically and compatible agents with promising success rates are currently available for paediatric dentistry practitioners. There is no evidence that justifies discarding the judicious use of DPC procedures in primary teeth.

Bone morphogenetic proteins in biomineralization of two endodontic restorative cements

To assess the effect of biodentine (BD) and MTA-angelus (MTA) on biocompatibility, BMP2, BMP4, and osteocalcin (OC) expression. Subcutaneously implanted tubes of four groups (MTA, BD, Control, and Sham) were kept over 15, 30, and 60 days; histological analyses were performed using H&E and Von Kossa; ELISA quantified IL-1β and IL-8 expression; and qRT-PCR verified gene expression of BMPs and OC. Sham showed slight changes in profile/intensity of inflammatory infiltrate in all periods. Control had an inflammatory score significantly higher than Sham at 15 days (p < .05). BD revealed a similar inflammatory response to Sham, without significant changes over periods. MTA group exhibited an increase in chronic inflammatory profile at 30 days, with significant reduction at 60 days, when compared to Sham (p < .05). At 30/60 days, experimental groups presented birefringent areas. At 30/60 days, BD and MTA significantly increase IL-1β compared to Control, whereas an increase in IL-8 was observed only in BD. At 30/60 days, BD produces an expression of BMP2 whereas MTA influenced BMP4 and OC. Materials tested are biocompatible and they have osteoinductive activity; the materials influenced the expression of the tested mediators differently, suggesting different affinities with the substrate and the dental substrates.

Postendodontic Pain after Pulpotomy or Root Canal Treatment in Mature Teeth with Carious Pulp Exposure: A Multicenter Randomized Controlled Trial

This equivalence, randomized, clinical trial aimed to compare the postoperative pain of root canal therapy (RCT) with pulpotomy with mineral trioxide aggregate (PMTA) or calcium-enriched mixture (PCEM) in permanent mature teeth. In seven academic centers, 550 cariously exposed pulps were included and randomly allocated into PMTA (n = 188), PCEM (n = 194), or RCT (n = 168) arms. Preoperative “Pain Intensity” (PI) on Numerical Rating Scale and postoperative PIs until day 7 were recorded. Patients' demographic and pre-/intra-/postoperative factors/conditions were recorded/analysed. The arms were homogeneous in terms of demographics. The mean preoperative PIs were similar (P=0.998), the mean sum PIs recorded during 10 postoperative intervals were comparable (P=0.939), and the trend/changes in pain relief were parallel (P=0.821) in all study arms. The incidences of preoperative moderate-severe pain in RCT, PMTA, and PCEM arms were 56.5%, 55.7%, and 56.7%, which after 24 hours considerably decreased to 13.1%, 10.6%, and 12.9%, respectively (P=0.578). The time span of endodontic procedures was statistically different; RCT = 69.73, PMTA = 35.37, and PCEM = 33.62 minutes (P < 0.001). Patients with greater preoperative pain, symptomatic apical periodontitis, or presence of PDL widening suffered more pain (P=0.002, 0.035, and 0.023, resp.); however, other pre-/intra-/postoperative factors/conditions were comparable. Pulpotomy with MTA/CEM and RCT demonstrate comparable and effective postoperative pain relief.

Chemical modification of MTA and CEM cement to decrease setting time and improve bioactivity properties by adding alkaline salts

Background. Mineral trioxide aggregate (MTA) and Calcium-enriched Mixture (CEM) cement are used for pulp capping since they induce the formation of a dentinal bridge. Long setting time is a shortcoming of these types of cement. This study aimed to assess the effect of the incorporation of some alkaline salts to MTA and CEM cement on their setting time, ion release profile, pH, and surface morphology.

Methods. In this in vitro experimental study, 5% calcium chloride (CaCl₂), calcium oxide (CaO), sodium fluoride (NaF), and calcium nitrate [Ca(NO₃)₂] were separately added to MTA and CEM cement. The primary and final setting times of the cements were measured using a Gillmore needle apparatus. The samples were immersed in simulated body fluid (SBF) for one, seven, and 14 days and subjected to x-ray diffraction (XRD) and scanning electron microscopy (SEM) for phase identification and surface morphology assessment. The change in the pH of solutions was studied, and the calcium ion release profile was determined using inductively coupled plasma atomic emission spectroscopy (ICP-AES). The data were analyzed with ANOVA, followed by post hoc tests.

Results. CaCl₂ and CaO decreased the setting time of MTA, and Ca(NO₃)₂ decreased the setting time of CEM cement. The incorporation of the salts increased the pH and calcium ion release from both cements, and hydroxyapatite deposits were noted to cover the surface of the samples (observed by SEM and confirmed by EDXA).

Conclusion. The incorporation of CaCl₂ and CaO into MTA and Ca(NO₃)₂ into CEM cement decreased their setting time and increased their pH and calcium ion release.

Histologic Evaluation of Artificial Floors Under MTA and Nano-Filled Resin-Modified Glass Ionomer Used to Repair Furcation Perforations in Dogs

Objective

This study aimed to compare the tissue reaction of two repair materials for furcation perforations, nano-filled resin modified glass ionomer (Nano-FRMGI) and mineral trioxide aggregate (MTA), used with or without an artificial floor.

Methods

A total of 96 teeth in 6 dogs were used for this study. After access cavities, root canals were prepared and obturated with gutta percha using cold lateral condensation technique. Perforations were then created on the floors of the pulp chambers. The perforations divided into four groups n=24/group that were sealed with MTA alone, MTA with calcium sulphate artificial floor (CSAF), FRMGI alone and Nano-FRMGI with CSAF. All access cavities were filled with composite resin. Two dogs were sacrificed at 1, 3, and 6 month. The experimental tooth along with the surrounding alveolar bone were cut in block sections and histologically evaluated for tissue response. Data were analyzed by Chi-square (P≤0.05).

Results

MTA and MTA with CSAF showed more bone and cementum apposition when compared to Nano-FRMGI at 6-month interval. MTA and MTA with CSAF showed less bone resorption, epithelium proliferation and inflammation compared to Nano-FRMGI at 6-month interval.

Conclusion

MTA with CSAF or MTA-alone show better outcomes in the repair of pulp chamber floor perforation.

Management of Symptomatic Horizontal Mid-root Fractures after Unsuccessful Orthograde Endodontic Retreatments

This case report describes the management of symptomatic horizontal mid-root fractures in previously traumatized central incisors, which initially had been treated endodontically and retreated afterwards. A 26-year-old female, who had suffered a traumatic injury to the maxillary anterior teeth, was referred owing to the failure of the corresponding orthograde endodontic retreatment and consequent pain/discomfort. Periapical radiographs and cone beam computed tomography showed that both central incisors had horizontal root fractures in their middle third, root canal fillings in their coronal segments, a considerable dislocation of the apical fragments and large radiolucent lesions between their apical segments and coronal fragments. Based on the obtained radiographic and clinical findings, a surgical endodontic retreatment approach for the main segments without removing the apical fragments was applied employing calcium-enriched mixture (CEM) cement as the retrograde biomaterial. Thirty-month clinical and radiographic follow-ups demonstrated successful outcomes. This case report showed the healing potential of horizontal mid-root fractures after surgical endodontics using CEM cement without removing apical fragments.

Histopathological, histoenzymological, immunohistochemical and immunofluorescence analysis of tissue response to sealing materials after furcation perforation

AIM

To evaluate in vivo tissue responses after sealing furcation perforations in dog's teeth with either Biodentine™, mineral trioxide aggregate (MTA) or gutta-percha, by means of histopathological, histoenzymological, immunohistochemical and immunofluorescence analysis.

METHODOLOGY

After root canal treatment, perforations were created in the central region of the pulp chamber floor using a round diamond bur and filled with one or other of the materials. The animals were euthanized after 120 days, and the teeth (n = 30) were processed for histopathological analysis of new mineralized tissue formation and collagen fibre reinsertion, immunohistochemical analysis of osteopontin (OPN) and alkaline phosphatase (ALP) and immunofluorescence analysis for bone morphogenetic protein (BMP-2), cementum attachment protein (CAP), bone sialoprotein (BSP), osteocalcin (OCN) and cementum protein1 (CEMP1). Histoenzymology was performed for TRAP activity and osteoclast count. Data were analysed statistically (α = 0.05) using chi-square and Kruskal-Wallis tests.

RESULTS

Gutta-percha did not induce mineralized tissue formation. MTA and Biodentine^TM formed mineralized tissue in 88% and 92% of specimens, respectively, with no significant difference (P > 0.05). Gutta-percha was associated with scattered collagen fibres parallel to the perforations. Groups treated with MTA or Biodentine^TM had partial fibre reinsertion perpendicular to the newly formed mineralized tissue. All materials induced OPN and ALP expression, weakest for gutta-percha and strongest for MTA (P < 0.05). Only MTA induced BMP-2, BSP, OCN, CAP and CEMP1 expression. Osteoclast counts were similar in all groups (P = 0.97).

CONCLUSIONS

Mineral trioxide aggregate and Biodentine^TM were biocompatible, with formation of mineralized tissue and partial reinsertion of collagen fibres. In addition, the participation of several molecules by which calcium silicate-based materials induce the formation of mineralized tissue were noted, with expression of ALP and OPN mineralization markers, without interference in the number of osteoclasts. Only MTA stimulated the expression of proteins associated with the formation of a cementum-like mineralized tissue.

Periradicular inflammatory response, bone resorption, and cementum repair after sealing of furcation perforation with mineral trioxide aggregate (MTA Angelus™) or Biodentine™

OBJECTIVE

This study assessed tissue responses after furcation perforation and immediate sealing with either Biodentine™ or MTA Angelus™.

MATERIAL AND METHODS

Sixty male Wistar rats were used (n = 6 per group/period). The mandibular first molars had the furcation mechanically exposed and sealed with either MTA or Biodentine™ and restored with silver amalgam. In an additional test group, teeth were sealed only with Biodentine™. Furcation sealing with gutta-percha and silver amalgam restoration served as positive control, and healthy untreated teeth were the negative control. Histological evaluation was performed after 14 or 21 days. Kruskal-Wallis and Dunn's post hoc tests were performed to analyze the extent and intensity of tissue inflammation, bone resorption, and cementum repair (p < 0.05).

RESULTS

Biodentine™ and MTA presented satisfactory results, showing a milder inflammatory response when compared to the control, regardless of the material used for coronal sealing and of the experimental period evaluated (p < 0.0001). All test groups showed less bone resorption than the positive control after 21 days (p < 0.05), and such differences were more pronounced in teeth restored with silver amalgam. Cementum repair was performed in 30% of MTA and Biodentine™ samples but not carried out in any positive control specimen.

CONCLUSIONS

Biodentine™ and MTA promoted similar responses when used to seal furcation perforations and should therefore be regarded as a promising alternative.

CLINICAL RELEVANCE

Knowledge about tissue responses to restorative materials is essential for improving root perforation sealing protocols. The present results showed that both Biodentine™ and MTA promoted appropriate periradicular tissue reactions in a preclinical test for evaluating furcation perforation treatments.

Management of merged external/internal root resorption using CEM cement: a case report

Chronic pulpal inflammation and infection are the main predisposing factors for internal and external root resorption (IRR & ERR); however, merging of IRR and ERR is a rare lesion which rigorously alters the anatomy of root canals. This study reports a case of merged IRR and ERR in an asymptomatic maxillary left central incisor in a 33-year old Caucasian woman that was managed by one-visit root canal therapy (RCT) using calcium-enriched mixture (CEM) cement. Radiographic examination showed a short root with under-filled root canal obturation associated with ERR/IRR and an apical lesion. After thorough chemo-mechanical preparation, the root canal was obturated with CEM cement; one week later, the access cavity was permanently restored. Clinical/radiographic examinations at 1-year follow-up revealed uneventful healing, reestablishment of lamina dura and stabilization of the resorptive defects. The treatment outcome demonstrates that one-visit RCT using CEM cement may be a viable treatment option in cases with merged external/internal root resorption. Further clinical trials with a larger number of cases are suggested to document a higher level of evidence.

Periodontal healing following non-surgical repair of an old perforation with pocket formation and oral communication

Iatrogenic perforations negatively impact the outcome of endodontic treatments. Studies on prognostic factors showed that perforations in the coronal third of the root with periodontal pocket formation have an unfavorable prognosis. A 36-year-old female was referred for endodontic evaluation of tooth #13 with a history of an iatrogenic perforation, happened 3 years ago. There was a sinus tract associated with perforation, 10 mm probing on the mesial and mesio-palatal, bleeding on probing, radiolucent lesion adjacent to the perforation and complete resorption of the interdental bone between teeth #13 and #12. After the treatment options were discussed, she chose to save the tooth. The tooth was accessed under rubber dam isolation, the perforation site was cleaned and disinfected using 0.5% sodium hypochlorite and sealed with calcium-enriched mixture cement. Eighteen months after treatment the tooth was functional and asymptomatic. The probing depths were normal without bleeding on probing. Radiographically, the interdental crestal bone formed between teeth #13 and #12. Despite all negative prognostic factors in this case (i.e., perforations in the coronal third, pocket formation, and radiolucent lesion), healing was unexpectedly achieved via non-surgical repair of the perforation. Further research on biological aspects of healing in the periodontium following iatrogenic perforations are recommended.

Effect of MTA and CEM on Mineralization-Associated Gene Expression in Stem Cells Derived from Apical Papilla

INTRODUCTION

This study assessed the effect of mineral trioxide aggregate (MTA) and calcium-enriched mixture (CEM) cement on odontogenic differentiation and mineralization of stem cells.

METHODS AND MATERIALS

After confirmation of stemness and homogeneity of stem cells derived from apical papilla (SCAPs) using flow cytometry, the cells were exposed for 3 weeks to either osteogenic medium (OS) or CEM extract+OS (CEM+OS) or MTA extract in OS (MTA+OS) or DMEM based regular culture media (negative control). Relative expression of alkaline phosphatase (ALP), dentine sialophosphoprotein (DSPP), osteocalcin (OSC), and osterix (SP7) were measured at days 14 and 21 using RT-qPCR method. At the same time points Alizarin Red staining method was used to assess mineralization potential of SCAPS. Gene expression changes analysis were made automatically using REST® software and a P<0.05 was considered significant.

RESULTS

After 2 weeks of exposure, expression of all genes were between 3 and 52 times the expression of GADPH (all were upregulated except SP7 in the control, P<0.05). After 3 weeks, relative expressions of the genes: ALP, SP7, DSPP, and OSC were respectively 275.9, 528.3, 98.4, and 603.7 times the expression of GADPH in the control group (OS). These were respectively 17.405, 29.2, 11.8, and 6.5 in CEM+OS group, and 163.8, 119.7, 102.5, and 723.9 in MTA+OS group. All of these were confirmed as upregulated (P<0.05) except for ALP and OSC of DM+CEM group. After 2 weeks, alizarin red staining showed similar mineralized nodules in OS, MTA+OS, and CEM+OS. In third week, larger nodules were seen in MTA+OS and OS, but not in CEM+OS.

CONCLUSION

After 2 weeks, gene expressions were almost comparable in OS, CEM+OS, and MTA+OS. After 3 weeks, OS and MTA+OS upregulated genes much greater than in 2nd week. However, upregulation in CEM+OS might not increase in 3rd week compared to those in 2nd week.

Efficacy of Pre-Medication with Ibuprofen on Post-Operative Pain after Pulpotomy in Primary Molars

INTRODUCTION

Pain management following dental procedures, particularly pulpotomies and extraction, is of great importance in pediatric dentistry. The aim of this study was to investigate the efficacy of pre-treatment with ibuprofen on post-operative pain following pulpotomy of primary molars.

METHODS AND MATERIALS

In a split mouth double-blinded randomized clinical trial, 49 children aging between 6-10 years old were given either ibuprofen or a placebo 45 min prior to the treatment. After pulpotomy and placement of a stainless steel crown (SSC), the pain level was evaluated using the Wong-Baker face visual analogue scale for up to 7 days post-treatment. McNemar and Wilcoxon tests were used for data analysis.

RESULTS

Forty-five patients were eligible to participate in this study. Pre-medication with ibuprofen significantly reduced pain during the first 24 h post-treatment (P=0.032). However, there was no significant difference in the pain levels between placebo and ibuprofen groups at 48 and 72 h post-treatment (P=0.154 and P=0.197, respectively). The number of times patients needed analgesics in ibuprofen group was significantly lower compared to that in the placebo group (P=0.008).

CONCLUSION

Pre-medication with ibuprofen resulted in less pain following pulpotomy and SSC placement in primary teeth.

Animal models used in furcation perforation studies: A systematic review and comprehensive synthesis of model characteristics

In order to systematise furcation perforation (FP) experimental animal models described in the literature and to determine whether there is evidence that a model is superior to others, MEDLINE/PubMed, SciELO and Cochrane Library were searched to find studies which used animal models of FP. Data were gathered concerning model characteristics, chosen groups, sample numbers, type of outcomes, journal and main area studied. Twenty-five articles were included in this systematic review, four conducted in rodent models, three in non-human primates and 18 in dogs. Medians were six animals and 34 teeth per study; 10 teeth per test group and, when performed, six teeth per control group. Twenty-four studies investigated the use of materials for FP repair; eight also tested adjuvant materials/substances. Although there is no model which can be described as ideal and superior than others for FP studies, dogs appear to possess the most suitable model characteristics.

Mineral trioxide aggregate and other bioactive endodontic cements: an updated overview - part II: other clinical applications and complications

Mineral trioxide aggregate (MTA) is a dental material used extensively for vital pulp therapies (VPT), protecting scaffolds during regenerative endodontic procedures, apical barriers in teeth with necrotic pulps and open apices, perforation repairs as well as root canal filling and root-end filling during surgical endodontics. A number of bioactive endodontic cements (BECs) have recently been introduced to the market. Most of these materials have calcium and silicate in their compositions; however, bioactivity is a common property of these cements. These materials include the following: BioAggregate, Biodentine, BioRoot RCS, calcium-enriched mixture cement, Endo-CPM, Endocem, EndoSequence, EndoBinder, EndoSeal MTA, iRoot, MicroMega MTA, MTA Bio, MTA Fillapex, MTA Plus, Neo MTA Plus, Ortho MTA, Quick-Set, Retro MTA, Tech Biosealer, and TheraCal LC. It has been claimed that these materials have properties similar to those of MTA but without the drawbacks. In Part I of this review, the available information on the chemical composition of the materials listed above was reviewed and their applications for VPT was discussed. In this article, the clinical applications of MTA and other BECs will be reviewed for apexification, regenerative endodontics, perforation repair, root canal filling, root-end filling, restorative procedures, periodontal defects and treatment of vertical and horizontal root fractures. In addition, the literature regarding the possible drawbacks of these materials following their clinical applications is reviewed. These drawbacks include their discolouration potential, systemic effects and retreatability following use as a root filling material. Based on selected keywords, all publications were searched regarding the use of MTA as well as BECs for the relevant clinical applications. Numerous publications were found regarding the use of BECs for various endodontic applications. The majority of these investigations compared BECs with MTA. Despite promising results for some materials, the number of publications using BECs for various clinical applications was limited. Furthermore, most studies had several methodological shortcomings and low levels of evidence.

In Vitro Sealing Properties of Calcium-Enriched Mixture and Mineral Trioxide Aggregate Orifice Barriers during Intra-Coronal Bleaching

Introduction:

This study aimed at evaluating the sealing properties of calcium-enriched mixture (CEM) compared to mineral trioxide aggregate (MTA) as a cervical barriers in intra-coronal bleaching.

Methods and Materials:

In this in vitro study, endodontic treatment was performed on 60 extracted human incisors and canines without canal calcification, caries, restorations, resorption or cracks. The teeth were then randomly divided into two experimental groups and two control groups (n=15). Then, CEM cement and MTA were applied as 3-mm intra-orifice barriers in the test groups; a mixture of sodium perborate and 30% hydrogen peroxide bleaching agents were placed within the pulp chamber for one week. Dye penetration method was used to evaluate the sealing ability of agents. Statistical analysis was performed using SPSS software. The Kendall coefficient was used to evaluate inter-observer agreement. The chi-squared test was used for statistical analysis.

Results:

The results showed that the penetration rates of CEM and MTA were the same as positive control group, with no significant differences (P=0.673 and P=0.408, respectively). However, there was a significant difference between the negative control group and CEM and MTA groups (P=0.001 for both groups). In addition, the sealing ability of MTA and CEM cement were not significantly different (P=0.682).

Conclusion:

During intra-coronal bleaching procedures CEM cement can be used as a cervical barrier with sealing properties comparable to that of MTA.

In Vitro Microleakage of Mineral Trioxide Aggregate, Calcium-Enriched Mixture Cement and Biodentine Intra-Orifice Barriers

Introduction:

This in vitro study compared the coronal microleakage of mineral trioxide aggregate (MTA), calcium-enriched mixture (CEM) cement and Biodentine as intra-orifice barriers.

Methods and Materials:

The study was conducted on 76 extracted single-canal human teeth. Their root canals were prepared using ProTaper rotary files and filled with gutta percha and AH-26 sealer using lateral condensation technique. Coronal 3 mm of the gutta percha was removed from the root canals and replaced randomly with MTA, CEM cement or Biodentine in the three experimental groups (n=22). A positive and a negative control group were also included (n=5). The entire root surfaces of all teeth were covered with two layers of nail varnish in such a way that only the access openings were not coated. In the negative control group, the access opening was also coated with nail varnish. All teeth were immersed in India ink and after clearing, the samples were evaluated under a stereomicroscope under ×10 magnification to assess the degree of dye penetration. The data were analyzed using the Kruskal-Wallis test. The level of significance was set at 0.05.

Results:

The negative control group showed no leakage while the positive control group showed significantly higher microleakage than the test groups (P>0.05). CEM cement had the lowest (0.175±0.068 mm) and MTA showed the highest dye penetration (0.238±0.159 mm) among the experimental groups; although these differences were not statistically significant (P=0.313).

Conclusion:

CEM cement exhibited the least microleakage as an intra-orifice barrier in endodontically treated teeth.

Furcation Perforation: Periradicular Tissue Response to Biodentine as a Repair Material by Histopathologic and Indirect Immunofluorescence Analyses

INTRODUCTION

The purpose of this study was to evaluate the in vivo response of periradicular tissues after sealing of furcation perforations with Biodentine, mineral trioxide aggregate (MTA), and gutta-percha by means of histopathologic and indirect immunofluorescence analyses.

METHODS

Thirty teeth of 3 dogs were divided into 3 groups: Biodentine (n = 14 teeth), MTA (negative control, n = 10 teeth), and gutta-percha (positive control, n = 6 teeth). After endodontic treatment, perforations were made on the center of the pulp chamber floor and filled with the materials. After 120 days, the animals were killed, and blocks containing the teeth and periradicular tissues were processed histotechnically for histopathologic semiquantitative (new mineralized tissue formation and bone resorption at the perforation site) and quantitative (thickness and area of newly formed mineralized tissue and number of inflammatory cells) analyses and RUNX2 immunofluorescence assay. Data were analyzed by χ², Fisher exact test, Mann-Whitney test, one-way analysis of variance, Kruskal-Wallis test, and Dunn posttest (α = 0.05).

RESULTS

MTA and Biodentine induced the formation of significantly more new mineralized tissue (P < .0001) than gutta-percha, which did not induce the formation of mineralized tissue in any case. Complete sealing of the perforations was more frequent with MTA, which formed mineralized tissue with greater thickness and area. Biodentine and MTA exhibited no bone resorption in the furcation region, fewer inflammatory cells, and greater RUNX2 immunostaining intensity than gutta-percha.

CONCLUSIONS

Although MTA presented higher frequency of complete sealing and greater thickness and area of newly formed mineralized tissue, Biodentine also had good histopathologic results and can be considered as an adequate furcation perforation repair material.

Histologic tissue response to furcation perforation repair using mineral trioxide aggregate or dental pulp stem cells loaded onto treated dentin matrix or tricalcium phosphate

Objectives

The aim of this study is to compare the effect of treated dentine matrix (TDM) and tricalcium phosphate (TCP) scaffolds on odontogenic differentiation and mineralization of dental pulp stem cells (DPSCs) in furcation perforations created in the pulp chamber floor of premolar teeth in dogs.

Material and methods

DPSCs were isolated and cultured from the dental pulp of the maxillary left second and third premolars of dogs. The DPSCs were loaded on TCP (SC+TCP) and TDM (SC+TDM) scaffolds and inserted into intentionally perforated pulp chamber floors of premolars in dogs; six teeth were used for each group. Three more groups of six specimens were created, and mineral trioxide aggregate (MTA), TDM, and TCP were inserted into the perforations to act as controls. An intact premolar and no treatment in the perforation site were used as positive and negative controls respectively. After 3 months, the animals were sacrificed and the type of inflammation, presence of dentine, continuation and type of cementum, type of connective tissue, and presence of foreign body reaction were evaluated, and significant differences were between groups determined using the Fisher’s exact test. The evaluation of the amount of inflammation and the percentage of new bone formation was evaluated using the Mann-Whitney U test.

Results

The negative control group was associated with severe inflammation and granulation tissue formation. In the positive control group, intact periodontal tissues and no inflammation were observed. Dentine bridge formation was not seen in specimens of any group. The specimens in the SC+TDM group were associated with significantly more bone formation than other groups (P < 0.001). The amount of inflammation was less than 10 % in specimens of all groups with the exception of three specimens in the TCP group that were categorized as 10–30 %. Chronic inflammation without foreign body reactions was the major pattern of inflammation in groups. Formation of cementum with a cellular and continuous appearance was seen in all specimens.

Conclusions

SC+TDM was associated with significantly more bone formation when used to repair uninfected furcation perforations in the premolar teeth of dogs.

Clinical relevance

Application of TDM as a biological scaffold in combination with DPSCs may offer an advantage during the repair of root perforation defects.

Effect of the plant-based hemostatic agent Ankaferd Blood Stopper® on the biocompatibility of mineral trioxide aggregate

Background

Due to the detrimental effect of blood contamination on the physico-chemical properties of mineral trioxide aggregate (MTA), obtaining an effective hemostasis in the surgical crypt during apical surgery is of paramount importance. The purpose of this in vivo study was to analyze the effect of Ankaferd Blood Stopper® (ABS) contamination on the biocompatibility of MTA.

Methods

Forty of 56 Wistar–Albino rats were divided randomly and equally into two groups (MTA and MTA-ABS) according to whether or not a hemostatic agent was used. The remaining 16 rats were designated as the control group. Rats in the experimental groups received freshly mixed MTA-Angelus in polyethylene tubes, which were inserted into monocortical bore holes created in their tibias. In the MTA-ABS group only, 0.5 mL of ABS solution was administered topically on the defect sites followed by implantation of MTA tubes. Inflammation, foreign-body reaction (FBR), necrosis, fibrosis, and new bone formation (NBF) were studied 7, 30, 60, and 90 days after implantation.

Results

On day7, statistically significant differences were found in tissue reactions with regard to NBF and necrosis (p = 0.044 and p = 0.024, respectively), the latter being observed in 40 % of the samples only in the MTA-ABS group. Slight inflammation in all groups was confined to day-7 only. Mild necrosis was present in the MTA-ABS group only on day-7. Severity of the foreign body reaction and fibrosis was limited. New bone formation increased gradually over time in all groups, reaching a maximum on day-90.

Conclusions

MTA and ABS-contaminated MTA are equally biocompatible. ABS does not impair the properties of MTA.

Electronic supplementary material

The online version of this article (doi:10.1186/s12903-016-0302-0) contains supplementary material, which is available to authorized users.

Comparison of Tooth Discoloration Induced by Calcium-Enriched Mixture and Mineral Trioxide Aggregate

Introduction:

The aim of this in vitro study was to evaluate the tooth discoloration induced by calcium-enriched mixture (CEM) cement and mineral trioxide aggregate (MTA).

Methods and Materials:

Forty five endodontically treated human maxillary central incisors were selected and divided into three groups (n=15) after removing the coronal 3 mm of the obturating materials. In the MTA group, white MTA plug was placed in pulp chamber and coronal zone of the root canal. In CEM cement group, CEM plug was placed in the tooth in the same manner. In both groups, a wet cotton pellet was placed in the access cavity and the teeth were temporarily sealed. After 24 h the teeth were restored with resin composite. In the negative control group the teeth were also restored with resin composite. The color change in the cervical third of teeth was measured with a colorimeter and was repeated 3 times for each specimen. The teeth were kept in artificial saliva for 6 months. After this period, the color change was measured again. Data were collected by Commission International de I'Eclairage's L*a*b color values, and corresponding ΔE values were calculated. The results were analyzed using the one-way ANOVA and post-hoc Tukey’s test with the significance level defined as 0.05.

Results:

There was no significant differences between CEM group and control group in mean discoloration. The mean tooth discoloration in MTA group was significantly greater than CEM and control groups (P<0.05).

Conclusion:

According to the result of the present study CEM cement did not induce tooth discoloration after six months. Therefore it can be used in vital pulp therapy of esthetically sensitive teeth.

Bacterial Leakage of Mineral Trioxide Aggregate, Calcium-Enriched Mixture and Biodentine as Furcation Perforation Repair Materials in Primary Molars

Introduction:

Adequate seal of iatrogenically perforated area within the root canal system can improve the long term treatment prognosis. This in vitro study evaluated the sealing ability of mineral trioxide aggregate (MTA), calcium-enriched mixture (CEM) cement and Biodentine in repair of furcation perforation in primary molars.

Methods and Materials:

A total of 61 freshly extracted primary mandibular second molars were randomly divided into three groups (n=17) and 10 teeth were put in negative (without perforation, n=5) and positive (perforated without repair, n=5) control groups. Turbidity was used as the criteria of bacterial leakage, when detected in the model of dual-chamber leakage. Data were analyzed using the Chi-Square and Kaplan-Meier survival analysis in SPSS software. The level of significance was set at 0.05.

Results:

All positive samples showed turbidity, whereas none of the negative samples allowed bacterial leakage. There was no significant difference between the number of turbidity samples in repaired teeth with all test materials (P=0.13). No significant difference was also detected in the mean survival time (P>0.05).

Conclusion:

CEM cement and Biodentine showed promising results as perforation repair materials and can be recommended as suitable alternatives of MTA for repair of furcation perforation of primary molars.

Coronal microleakage of three different dental biomaterials as intra-orifice barrier during nonvital bleaching

Background:

This study was designed to assess the microleakage of glass-ionomer (GI), mineral trioxide aggregate (MTA), and calcium-enriched mixture (CEM) cement as coronal orifice barrier during walking bleaching.

Materials and Methods:

In this experimental study, endodontic treatment was done for 70 extracted human incisors without canal calcification, caries, restoration, resorption, or cracks. The teeth were then divided into three experimental using “Simple randomization allocation” (n = 20) and two control groups (n = 5). The three cements were applied as 3-mm intra-orifice barrier in test groups, and bleaching process was then conducted using a mixture of sodium perborate powder and distilled water, for 9 days. For leakage evaluation, bovine serum albumin marker was traced in a dual-chamber technique with Bradford indicator. The Kruskal-Wallis and Mann-Whitney tests were used for statistical analysis.

Results:

The mean ± standard deviation leakage of samples from negative control, positive control, GI, MTA, and CEM cement groups were 0.0, 8.9 ± 0.03, 0.47 ± 0.02, 0.48 ± 0.02, and 0.49 ± 0.02 mg/mL, respectively. Statistical analysis showed no significant difference between three experimental groups (P > 0.05).

Conclusion:

It is concluded that GI, MTA, and CEM cements are considered as suitable intra-orifice barrier to provide coronal seal during walking bleaching.

Calcium silicate-based cements: composition, properties, and clinical applications

Mineral trioxide aggregate (MTA) is a calcium silicate-based cement (CSC) commonly used in endodontic procedures involving pulpal regeneration and hard tissue repair, such as pulp capping, pulpotomy, apexogenesis, apexification, perforation repair, and root-end filling. Despite the superior laboratory and clinical performance of MTA in comparison with previous endodontic repair cements, such as Ca(OH)₂ , MTA has poor handling properties and a long setting time. New CSC have been commercially launched and marketed to overcome the limitations of MTA. The aim of the present review was to explore the available literature on new CSC products, and to give evidence-based recommendations for the clinical use of these materials. Within the limitations of the available data in the literature regarding the properties and performance of the new CSC, the newer products could be promising alternatives to MTA; however, further research is required to support this assumption.

Cementoblastic lineage formation in the cross-talk between stem cells of human exfoliated deciduous teeth and epithelial rests of Malassez cells

OBJECTIVES

The purpose of this study was to evaluate the synergistic effect of epithelial rests of Malassez cells (ERM) and transforming growth factor-β1 (TGF-β1) on proliferation, cementogenic and osteogenic differentiation of stem cells derived from human exfoliated deciduous teeth (SHED).

MATERIALS AND METHODS

SHED were co-cultured with ERM with/without TGF-β1. Then, SHED proliferation, morphological appearance, alkaline phosphatase (ALP) activity, mineralization behaviour and gene/protein expression of cemento/osteoblastic phenotype were evaluated.

RESULTS

TGF-β1 enhanced SHED proliferation when either cultured alone or co-cultured with ERM. ERM induced the cementoblastic differentiation of SHED which was significantly accelerated when treated with TGF-β1. This activity was demonstrated by high ALP activity, strong mineral deposition and upregulation of cementum/bone-related gene and protein expressions (i.e. ALP, collagen type I, bone sialoprotein, osteocalcin and cementum attachment protein).

CONCLUSIONS

ERM were able to induce SHED differentiation along the cemento/osteoblastic lineage that was triggered in the presence of TGF-β1.

CLINICAL RELEVANCE

The cemento/osteoblastic differentiation capability of SHED possesses a therapeutic potential in endodontic and periodontal tissue engineering.

Cementoblastic lineage formation in the cross-talk between stem cells of human exfoliated deciduous teeth and epithelial rests of Malassez cells

OBJECTIVES

The purpose of this study was to evaluate the synergistic effect of epithelial rests of Malassez cells (ERM) and transforming growth factor-β1 (TGF-β1) on proliferation, cementogenic and osteogenic differentiation of stem cells derived from human exfoliated deciduous teeth (SHED).

MATERIALS AND METHODS

SHED were co-cultured with ERM with/without TGF-β1. Then, SHED proliferation, morphological appearance, alkaline phosphatase (ALP) activity, mineralization behaviour and gene/protein expression of cemento/osteoblastic phenotype were evaluated.

RESULTS

TGF-β1 enhanced SHED proliferation when either cultured alone or co-cultured with ERM. ERM induced the cementoblastic differentiation of SHED which was significantly accelerated when treated with TGF-β1. This activity was demonstrated by high ALP activity, strong mineral deposition and upregulation of cementum/bone-related gene and protein expressions (i.e. ALP, collagen type I, bone sialoprotein, osteocalcin and cementum attachment protein).

CONCLUSIONS

ERM were able to induce SHED differentiation along the cemento/osteoblastic lineage that was triggered in the presence of TGF-β1.

CLINICAL RELEVANCE

The cemento/osteoblastic differentiation capability of SHED possesses a therapeutic potential in endodontic and periodontal tissue engineering.

Investigating the mutagenic effects of three commonly used pulpotomy agents using the ames test

PURPOSE

The mutagenic potency of materials used in dentistry is of great concern. The Ames test is a bacterial reverse mutation assay, which is used to determine the mutagenicity potential of chemicals. In this study, the Ames test was used to compare mutagenic effects of three pulpotomy agents, namely, CEM cement, formocresol and ferric sulfate.

METHODS

TA100 strain of Salmonella typhimurium was used to evaluate mutagenicity of different concentrations of pulpotomy materials in the presence and absence of enzymatic system found in rat liver S9 fraction. Negative controls were 1% dimethyl sulfoxide and water. The positive controls were sodium azide and 2-aminoanthracene. The number of colonies per plate was counted. The material was regarded mutagenic if the number of histidine revertant colonies was twice or more than the spontaneous revertant colonies (Ames mutagenicity ratio).

RESULTS

Ferric sulfate was found mutagenic in the concentrations prepared by addition of 50 µL of its 1 in 100 and 1 in 1000 times diluted solutions to the culture medium in the absence of S9 fraction (Ames test ratios of 2.8 and 2.2, respectively). Formocresol showed strong toxicity toward TA100 strain of S. typhimurium up to the concentration as low achieved using 1000 times diluted solution of the original preparation, particularly in the presence of S9 fraction. Ames assay failed to detect significant reverse mutations in all the concentrations of CEM cement.

CONCLUSION

In contrast to formocresol and ferric sulfate, CEM cement is a less toxic and non-mutagenic agent.

The Effect of Thickness on the Sealing Ability of CEM Cement as a Root-end Filling Material

Background and aims. Different materials have been used for root-end filling during surgical endodontic treatment. The aim of this in vitro study was to evaluate the dye penetration in different thicknesses of calcium enriched mixture (CEM) cement as root-end filling material. Materials and methods. Following root canal filling in 70 extracted human single-rooted premolar teeth, the apical 3 mm of their root-ends was resected; the root-end cavities with depths of 1, 2 and 3 mm were prepared by ultrasonic retrotips and filled with CEM cement. After setting of cement, the roots were immersed in 2% Rhodamine B and the dye leakage was measured under stereomicroscope (×16) using Image J software. The data were analyzed by one-way ANOVA and Bonferroni post hoc tests at 5% significance level. Results. The means and standard deviations of dye penetration in the 1, 2, and 3 mm groups were 3395.5±1893.4, 3410.4±1440.5, and 2581.6±1852.9 μm, respectively. The one-way ANOVA analysis indicated significant differences (P < 0.001); however, the Bonferroni post hoc test revealed that only the positive control group differed significantly from the experimental groups (P < 0.001). Conclusion. The findings demonstrated CEM cement to have an adequate root-end sealing ability in 3-mm thickness.

Effect of calcium chloride on physical properties of calcium-enriched mixture cement

The aim of this study was to evaluate the effect of adding 10% calcium chloride (CaCl2) on the setting time, solubility and the pH of calcium-enriched mixture (CEM) cement. Setting time was assessed in accordance with American Dental Association specification N°57. Solubility was measured at 24 and 72 h, 7 and 14 days in hydrated and dehydrated conditions by calculating weight change. The pH of MiliQ water in which the CEM cement samples were immersed was measured immediately after each time interval with and without the addition of CaCl2. The data were analysed using the Mann-Whitney U-test and the Student's t-test. The initial setting time was significantly decreased after the addition of 10% CaCl2. The pH of water increased immediately when in contact with the cements in both groups. The weight loss of hydrated and dehydrated specimens was more than 3% and was significantly reduced by the addition of 10% CaCl2.

Current perspectives of bio-ceramic technology in endodontics: calcium enriched mixture cement - review of its composition, properties and applications

Advancements in bio-ceramic technology has revolutionised endodontic material science by enhancing the treatment outcome for patients. This class of dental materials conciliates excellent biocompatibility with high osseoconductivity that render them ideal for endodontic care. Few recently introduced bio-ceramic materials have shown considerable clinical success over their early generations in terms of good handling characteristics. Calcium enriched mixture (CEM) cement, Endosequence sealer, and root repair materials, Biodentine and BioAggregate are the new classes of bio-ceramic materials. The aim of this literature review is to present investigations regarding properties and applications of CEM cement in endodontics. A review of the existing literature was performed by using electronic and hand searching methods for CEM cement from January 2006 to December 2013. CEM cement has a different chemical composition from that of mineral trioxide aggregate (MTA) but has similar clinical applications. It combines the biocompatibility of MTA with more efficient characteristics, such as significantly shorter setting time, good handling characteristics, no staining of tooth and effective seal against bacterial leakage.

Nonsurgical management of an extensive endodontic lesion in an orthodontic patient by calcium-enriched mixture apical plug

Periapical lesion is a general term used to describe the periapical inflammatory process that occurs in response to the invasion of micro-organisms in the root canal system as well as inflamed vital pulp. This phenomenon necessitates endodontic intervention and if the necrosis has occurred prior to tooth maturation, wide patency of the apical foramen requires some treatment modalities such as apexification or apical plug. Orthodontic treatment, on the other hand, is cautiously done for previously traumatized teeth due to increased risk for necrosis of the compromised tooth. This article tends to review the successful treatment process with calcium-enriched mixture (CEM) cement apical plug for an immature previously traumatized incisor tooth with an extensive periapical lesion, which was under orthodontic treatment as well.

Efficacy of MTA and CEM Cement with Collagen Membranes for Treatment of Class II Furcation Defects

OBJECTIVES

This study aimed to compare the efficacy of MTA and CEM cement in Class II furcation defects in human mandibular molars.

MATERIALS AND METHODS

Forty furcation defects were treated in 16 patients with chronic periodontitis. The clinical parameters of probing depth (PD), vertical and horizontal clinical attachment levels (VCAL and HCAL), open vertical and horizontal furcation depths (OVFD and OHFD), and gingival margin level (GML) were measured at baseline and at 3- and 6-month (re-entry surgery) postoperatively. Data were analyzed at a significance level of P<0.05.

RESULTS

Use of MTA and CEM caused significant decreases in PD, VCAL, HCAL, OVFD and OHFD at re-entry, with no statistically significant differences between the two treatment options in soft and hard tissue parameters.

CONCLUSION

Both treatment modalities caused significant gains in attachment levels and bone fills, proving efficacy for treatment of Class II furcation involvements.

Surgical management of a failed internal root resorption treatment: a histological and clinical report

This article presents the successful surgical management of a failed mineral trioxide aggregate (MTA) orthograde obturation of a tooth with a history of impact trauma and perforated internal root resorption. A symptomatic maxillary lateral incisor with a history of perforation due to internal root resorption and nonsurgical repair using MTA was referred. Unintentional overfill of the defect with MTA had occurred 4 yr before the initial visit. The excess MTA had since disappeared, and a radiolucent lesion adjacent to the perforation site was evident radiographically. Surgical endodontic retreatment was performed using calcium enriched mixture (CEM) cement as a repair material. Histological examination of the lesion revealed granulation tissue with chronic inflammation, and small fragments of MTA encapsulated within fibroconnective tissue. At the one and two year follow up exams, all signs and symptoms of disease had resolved and the tooth was functional. Complete radiographic healing of the lesion was observed two years after the initial visit. This case report illustrates how the selection of an appropriate approach to treatment of a perforation can affect the long term prognosis of a tooth. In addition, extrusion of MTA into a periradicular lesion should be avoided.

Gene expression and cytokine release during odontogenic differentiation of human dental pulp stem cells induced by 2 endodontic biomaterials

INTRODUCTION

Mineral trioxide aggregate (MTA) and calcium-enriched mixture (CEM) have shown osteogenic/cementogenic/dentinogenic activities; however, their mechanism of action is not fully understood. We aimed to evaluate the effect of these biomaterials on odontogenic differentiation of human dental pulp stem cells (DPSCs).

METHODS

Flow cytometry with stem cell markers for the confirmation of stemness and homogeneity was first performed. Then isolated DPSCs were seeded on prepared discs of MTA, CEM, differentiation medium (DM), and growth medium (GM) and incubated up to 14 days. Concentrations of transforming growth factor-β1, bone morphogenetic protein (BMP)2, BMP4, and fibroblast growth factor 4 were measured at each interval using an enzyme-linked immunosorbent assay reader. Gene expression of dentin sialophosphoprotein, dentin matrix protein 1, and the cytokines were evaluated by reverse-transcription polymerase chain reaction. To evaluate the cell morphology, scanning electron micrographs were taken; mineralization potential was evaluated using alizarin red S staining.

RESULTS

Scanning electron micrographs showed that DPSCs spread/adhered/proliferated similarly on MTA and CEM. On day 14, alizarin red S staining confirmed that mineralization occurred in all groups except GM. Expressions of dentin matrix protein 1 and dentin sialophosphoprotein genes were similar in the CEM, MTA, and DM groups; they were significantly higher compared with the GM group (P < .05). A greater amount of transforming growth factor-β1 gene was expressed in MTA compared with the other groups (P < .05). However, the expression of fibroblast growth factor 4 and BMP2 genes was significantly greater in the CEM group (P < .05). In all the tested groups, the expression of BMP4 was less than GM (P < .01); however, CEM and DM were similar but more than MTA (P < .05). Concentrations of protein product detected using an enzyme-linked immunosorbent assay reader confirmed these gene expressions.

CONCLUSIONS

MTA and CEM can induce osteo-/odontogenic-like phenotype differentiation of human DPSCs; however, they stimulate different gene expressions and growth factor release.

Comparison of skin test reactivity of two endodontic biomaterials in rabbits

In this in vivo study, the skin reactivity of rabbits to Mineral Trioxide Aggregate (MTA) and Calcium Enriched Mixture (CEM) was compared. Sixteen albino rabbits were used. The dorsal skin in three areas (2 x 2 cm) of the rabbits was shaved 24 h prior to the test. The areas were randomly covered with freshly mixed biomaterials [MTA (n = 16), CEM (n = 16) and normal saline (control; n = 16)], sterile gauze and bandages were placed for 4 h and the biomaterials were washed. The surface areas of the reactive skin sections were examined by naked eye and measured in 1, 24, 48 and 72 h using the Cavalier technique. The animals were then sacrificed and histological sections were prepared for blind examination. Results of macroscopic examination revealed a significant difference (p = 0.003) between the average erythematous surface areas induced by MTA (1.61 +/- 0.32) and CEM (0.5 +/- 0.16). Results of histological examination showed that the highest inflammation was observed in MTA, followed by CEM and control groups. Comparison of the difference in inflammatory cell count between each group revealed statistically significant differences in all cases (p < 0.001). The results demonstrated that the biocompatibility of CEM cement is higher than MTA; CEM can be considered as a suitable endodontic biomaterial.

Bond strength of composite resin to pulp capping biomaterials after application of three different bonding systems

Background and aims. Bonding of composite resin filling materials to pulp protecting agents produces an adhesive joint which is important for the quality of filling as well as success of restoration. We aimed to assess the bond strength of composite resin to three pulp capping biomaterials: Pro Root mineral trioxide aggregate (PMTA), Root MTA (RMTA) and calcium enriched mixture (CEM) cement, using three bonding systems [a total-etch (Single Bond) and two self-etch systems (Protect bond and SE Bond)].

Materials and methods. Ninety acrylic molds, each containing a 6×2-mm hole, were divided into 3 groups and filled with PMTA, RMTA and CEM cements. The samples in each experimental group were then randomly divided into 3 sub-groups; Single Bond, Protect Bond and SE Bond bonding systems were applied to the tested materials. Cylindrical forms of composite resin (Z100, 2×2 mm) were placed onto the samples and cured. Shear bond strength values were measured for 9 subgroups using a universal testing machine. Data were analyzed using two-way ANOVA.

Results. The average shear bond strengths of Z100 composite resin after application of Single Bond, Protect Bond and SE Bond systems were as follows; PMTA: 5.1±2.42, 4.56±1.96 and 4.52±1.7; RMTA: 4.71±1.77, 4.31±0.56 and 4.79±1.88; and CEM cement: 4.75±1.1, 4.54±1.59 and 4.64±1.78 MPa, respectively. The type of pulp capping material, bonding system and their interacting effects did not have a significant effect on the bond strengths of composite resin to pulp capping biomaterials.

Conclusion. Within the limitations of this in vitrostudy, bond strength of composite resin to two types of MTA as well as CEM cement were similar following application of the total-etch or self-etch bonding systems.

Comparison of shear bond strength of resin-modified glass ionomer and composite resin to three pulp capping agents

Background and aims. Present study was designed to compare the bonding strength of resin-modified glass ionomer (RMGI) and composite resin to mineral trioxide aggregate (MTA), MTA mixed with Na2HPO4 (NAMTA), and calcium-enriched mixture (CEM).

Materials and methods. Thirty specimens of each CEM, NAMTA, and MTA were prepared. Composite and RMGI restorations were then placed on the samples (15 samples in six subgroups). Shear bond strength was assessed using universal testing machine. Data were analyzed with two-way ANOVA and post-hoc Tukey test. To compare the bond strength in subgroups, one-away ANOVA was applied. Significance level was set at P < 0.05.

Results. Bond strength was significantly higher to composite samples compared to RMGI samples (p<0.001). The difference in bond strength of composite samples between MTA and CEM subgroups (P=0.026) as well as MTA and NAMTA subgroups (P= 0.019) was significant, but the difference between NAMTA and CEM subgroups (P=0.56) was not significant. The differences in bond strength in subgroups of RMGI group were not significant (P>0.05).

Conclusion. Regarding shear bond strength to the tested substrates, composite was shown to be superior to RMGI. The bond of resin composite to MTA was weaker than that to CEM and NAMTA.

Vital pulp therapy with three different pulpotomy agents in immature molars: a case report

INTRODUCTION

This case report describes apexogenesis treatment of three molar teeth of an 8-year-old boy using three different pulpotomy agents.

METHODS

Pulpotomy was performed on decayed immature molar teeth with established irreversible pulpitis and the remaining pulp was capped with either zinc oxide eugenol, ProRoot mineral trioxide aggregate or calcium-enriched mixture (CEM) cement. Teeth were restored with stainless steel crowns.

RESULTS

Eighteen months clinical and radiographic follow-up revealed successful preservation of pulpal vitality with continued root development in all treated teeth.

CONCLUSION

Based on this case report, CEM cement may be an alternative option for pulpotomy treatment of immature permanent molars.