Chemico-physical and mechanical evaluation of three calcium silicate-based pulp capping materials

Comparison of push-out bond strength and apical microleakage of different calcium silicate-based cements after using EDTA, chitosan and phytic acid irrigations

This research was aimed to evaluate push-out bond strength and apical-microleakage after application of three different calcium silicate-based cements with irrigation solutions on simulated immature teeth. 40 maxillary permanent canine teeth were used for push-out bond strength test, and 120 maxillary permanent incisors were used for microleakage evaluation. 120 root slices were divided into four main groups (EDTA, Chitosan, Phytic acid, and Saline) and immersed these solutiouns according to irrigation procedures. Each irrigation group was divided into 3 subgroups (Biodentine, MTA Repair HP, and NeoPUTTY). The prepared teeth were divided into four groups according to irrigation procedure for microleakage test. EDTA irrigation with Biodentine group showed highest push-out bond strength value and saline group with Neoputty showed the lowest push-out bond strength value. The highest microleakage value was seen in saline group with MTA Repair HP, while the lowest microleakage value was observed chitosan with Biodentine group. Chitosan and phytic acid solutions can be recommended as an alternative irrigation solution to 17% EDTA in single-session apexification treatment, since they are non-toxic, naturally occurring materials, effectively remove the smear layer, and have a positive effect on bond strength and apical leakage. RESEARCH HIGHLIGHTS: One of the factors affecting the long-term success of root canal treatment is a hermetic seal. Non-hermetic or inadequate filling triggers a chronic inflammatory reaction in periapical tissues, causing fluids to enter the spaces and negatively affecting the success of the treatment. Therefore, this study will help clinicians choose the right biomaterial and irrigation solution that will affect the success of root canal treatment.

Biological properties versus solubility of endodontic sealers and cements

Endodontic sealers and cements used in root canal treatment have different compositions and properties. Common to all materials is that their primary goal is to fill gaps and voids, making a permanent seal of the root canal system. Furthermore, aspects such as antibacterial properties, cytotoxicity, setting time, solubility and biocompatibility are also crucial and ought to be considered. Over the years, a shift in the view on the importance of these aspects has ocurred. Whereas the antibacterial properties were considered important when the technical factors in endodontics were less developed, the sealing ability and biocompatibility have later been considered the most critical factors. The introduction of tricalcium silicate cements and sealers has led to a renewed interest in material properties, as these cements seem to have good sealing ability and at the same time combine favourable antimicrobial effects with excellent biocompatibility. This review discusses how the various properties of root canal sealers and cements may conflict with the primary aim of providing a permanent seal of the root canal system.

Biocompatibility of mineral trioxide aggregate and biodentine as root-end filling materials: an in vivo study

This study evaluated the biocompatibility of mineral trioxide aggregate (MTA) and Biodentine (BD) as root-end filling materials. Six mongrel dogs were divided into two equal groups according to the evaluation period; group A: one month and group B: three months. Three premolars of the same quadrant in each arch were used, summing up 36 teeth (6 teeth/dog). These teeth were randomly subdivided into three subgroups according to the root-end filling material used: MTA, BD and no root-end filling material (control). Endodontic access cavities were performed for induction of periapical pathosis. After the infection period, root canal instrumentation and obturation were accomplished. One day after root canal procedures, root-end surgery was performed. Surgical access was achieved and the root-end was resected approximately 3 mm above the apex. Root-end cavity was prepared ultrasonically and filled with the tested materials. All samples were evaluated by radiography and histopathology (Inflammation and new hard tissue formation). Data were collected and subjected to statistical analysis. In group A, MTA subgroup exhibited significant higher mean inflammatory score than BD subgroup (P < 0.05) while no significant difference was recorded between MTA and BD subgroups in group B (P > 0.05). Regarding mean mineralization score, there was no significant difference between all subgroups in both groups A and B (P > 0.05). Biodentine exhibited favorable biocompatibility in the initial stage of healing than MTA and comparable biomineralization. Clinical relevance: Biodentine could be considered as an acceptable alternative to MTA in peri-radicular surgeries.

Shear bond strength of calcium silicate-based cements to glass ionomers

BACKGROUND

A shear bond strength between the biomaterial and restorative material is crucial for minimizing bacterial microleakage and ensuring a favorable long-term prognosis for vital pulp therapy. This study aimed to conduct a comparative evaluation of the shear bond strength between calcium silicate-based biomaterials utilized in vital pulp treatment and various glass ionomer cement materials, both with and without the application of adhesive agents.

METHODS

A total of 270 acrylic blocks, each featuring cavities measuring 4 mm in diameter and 2 mm in depth, were prepared. Calcium silicate-containing biomaterials (ProRoot MTA, Medcem Pure Portland Cement, and Medcem MTA), following manufacturers' instructions, were placed within the voids in the acrylic blocks and allowed to set for the recommended durations. The biomaterial samples were randomly categorized into three groups based on the restorative material to be applied: conventional glass ionomer cement, resin-modified glass ionomer cement, and bioactive restorative material. Using cylindrical molds with a diameter of 3.2 mm and a height of 3 mm, restorative materials were applied to the biomaterials in two different methods, contingent on whether adhesive was administered. After all samples were incubated in an oven at 37 °C for 24 h, shear bond strength values were measured utilizing a universal testing device. The obtained data were statistically evaluated using ANOVA and post-hoc Tukey tests.

RESULTS

The highest shear bond strength value was noted in the Medcem MTA + ACTIVA bioactive restorative material group with adhesive application, while the lowest shear bond strength value was observed in the ProRoot MTA White + Equia Forte HT Fil group without adhesive application (P < 0.05).

CONCLUSION

Activa Bioactive Restorative may be considered a suitable restorative material in combination with calcium silicate-based biomaterials for vital pulp treatment. The application of adhesives to calcium silicate-based biomaterials can effectively address the technical limitations.

Direct pulp capping procedures - Evidence and practice

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

Physicochemical and Antibacterial Properties of Bioactive Retrograde Filling Materials

The purpose of the present study was to evaluate the physicochemical properties and antibacterial activity of three calcium silicate cements. Mineral trioxide aggregate (MTA Biorep “BR”), Biodentine (BD) and Well-Root PT (WR) materials were investigated using scanning electron microscopy (SEM) at 24, 72 and 168 h of immersion in phosphate buffered saline (PBS). The antibacterial activity against Enterococcus faecalis (E. faecalis), the solubility, roughness, pH changes and water contact angle were also analyzed. All results were statistically analyzed using a one-way analysis of variance test. Statistically significant lower pH was detected for BD than WR and BR (p < 0.05). No statistical difference was found among the three materials for the efficacy of kill against E. faecalis (p > 0.05). Good antibacterial activity was observed (kill 50% of bacteria) after 24 h of contact. The wettability and the roughness of BR were higher than for the other cements (p < 0.05). BD was more soluble than WR and BR (p < 0.05). In conclusion, the use of bioceramic cements as retrograde materials may play an important role in controlling bacterial growth and in the development of calcium phosphate surface layer to support healing. Moreover, the premixed cement was easier to use than powder−liquid cement.

Inflammatory response and immunohistochemical characterization of experimental calcium silicate-based perforation repair material

This study compares the immunohistochemical reaction of a new experimental tricalcium silicate perforation repair material to mineral trioxide aggregate (MTA) and Biodentine. A total of 162 mature premolar teeth from 12 dogs were divided into three experimental groups (n = 54 teeth each) according to the evaluation period: 1, 2 and 3 months. Each group was further divided into two equal subgroups (n = 27 teeth each) according to the time of repair: immediate repair and delayed repair. Each subgroup was subdivided according to the material used into three experimental subdivisions (n = 8 teeth each): MTA, Biodentine (Septodont) and experimental material, and two control subdivisions: positive control (n = 2 teeth) and negative control (one tooth). Under general anaesthesia, access cavity was done. Cleaning and shaping were performed using ProTaper universal rotary instruments. The canals were obturated using cold lateral compaction technique with Gutta percha and Adseal sealer. Furcation perforations were created then randomly sealed using the three materials either immediately or after one month (delayed repair). Inflammatory cell count and immunohistochemical analysis of osteopontin-positive area fraction were digitally analysed using the ImageJ software. Delayed furcal perforation repair showed significantly higher inflammatory cell count than immediate repair. No significant difference in inflammatory cell count and immunohistochemical analysis was detected between the three tested materials. The immunohistochemical analysis revealed the highest immunopositive area fraction in the 3-month evaluation period. The experimental tricalcium silicate cement performed similarly to Biodentine and MTA regarding the osteopontin expression during perforation repair, suggesting it is a suitable alternative with favourable handling characters.

Present status and future directions: Hydraulic materials for endodontic use

BACKGROUND

Hydraulic materials are used in Endodontics due to their hydration characteristics namely the formation of calcium hydroxide when mixing with water and also because of their hydraulic properties. These materials are presented in various consistencies and delivery methods. They are composed primarily of tricalcium and dicalcium silicate, and also include a radiopacifier, additives and an aqueous or a non-aqueous vehicle. Only materials whose primary reaction is with water can be classified as hydraulic.

OBJECTIVES

Review of the classification of hydraulic materials by Camilleri and the literature pertaining to specific uses of hydraulic cements in endodontics namely intra-coronal, intra-radicular and extra-radicular. Review of the literature on the material properties linked to specific uses providing the current status of these materials after which future trends and gaps in knowledge could be identified.

METHODS

The literature was reviewed using PUBMED, and for each clinical use, the in vitro properties such as physical, chemical, biological and antimicrobial characteristics and clinical data were extracted and evaluated.

RESULTS

A large number of publications were retrieved for each clinical use and these were grouped depending on the property type being investigated.

CONCLUSIONS

The hydraulic cements have made a difference in clinical outcomes. The main shortcoming is the poor testing methodologies employed which provide very limited information and also inhibits adequate clinical translation. Furthermore, the clinical protocols need to be updated to enable the materials to be employed effectively.

Biocompatibility of NeoMTA Plus® versus MTA Angelus as delayed furcation perforation repair materials in a dog model

BACKGROUND

The biocompatibility of NeoMTA Plus® (Avlon BioMed Inc., Bradenton, Fl) as a furcal perforation repair material is not fully understood. This study compares the biocompatibility of Mineral Trioxide Aggregate (MTA Angelus) and NeoMTA Plus® as delayed furcation perforation repair materials.

METHODS

Pulpotomy and root canal obturation were performed in 72 premolars in six mongrel dogs and then a standardized furcal perforation was performed. The coronal access was left open for three weeks. After curetting, cleaning and drying of the perforations, these teeth were divided into three equal groups (N = 24 teeth/ 2 dogs each) according to the material used for perforation repair; group I: NeoMTA Plus®, group II: MTA Angelus and group III: no material (positive control). The coronal access cavities were sealed with a filling material. The inflammatory cell count and qualitative pathology (presence of calcific bridge, configuration of fibrous tissue formed, examination of tissue surrounding the furcation area, histology of intraradicular bone and the inflammatory nature of tissues) were carried out after one week (subgroup A, N = 8 teeth), one month (subgroup B, N = 8 teeth) and three months (subgroup C, N = 8 teeth). The inflammatory cell count was expressed as mean ± SD and statistically analyzed. P-value < 0.05 was considered significant.

RESULTS

In all subgroups, the control group exhibited the highest number of inflammatory cell count, followed by MTA Angelus group and the least inflammatory cell count was shown by NeoMTA Plus® group. There was a significant difference in the inflammatory cell count between the NeoMTA Plus® and MTA Angelus after one week (P < 0.05) while no significant differences were recorded between them after one month and three months (P > 0.05). In contrast to group II, there was no significant differences in inflammatory cell count between the subgroups in groups I and III (P > 0.05). NeoMTA Plus® exhibited better qualitative pathological features than MTA Angelus after one week and nearly similar features after one month and three months of repair.

CONCLUSION

NeoMTA Plus® has a better early biocompatibility than MTA Angelus after one week of delayed furcation perforation repair and a similar late biocompatibility after one month and three months.

Minimal Intervention in Dentistry: A Literature Review on Biodentine as a Bioactive Pulp Capping Material

Root canal treatment has been the treatment of choice for carious pulp exposures. In the perspective of minimally invasive dentistry and preventive endodontics, a direct pulp capping procedure with a reliable bioactive material may be considered an alternative approach provided that the pulp status is favorable. However, the treatment of pulp exposure by pulp capping is still a controversial issue with no clear literature available on this topic, leaving the concerned practitioner more confused than satisfied. Biodentine is a relatively new bioactive material explored for vital pulp therapy procedures. This article discusses its role in direct pulp capping procedures. A thorough literature search of the database was done using PubMed, Google Scholar, and Scopus using the keywords preventive endodontics, calcium silicate cement, direct pulp capping, Biodentine, and vital pulp therapy. Reference mining of the articles that were identified was used to locate other papers and enrich the findings. No limits were imposed on the year of publication, but only articles in English were considered. This paper is aimed at reviewing the current literature on Biodentine as a direct pulp capping material. The review will provide a better understanding of Biodentine's properties and can aid in the decision-making process for maintaining the vitality of exposed dental pulp with minimal intervention.

Influence of insulin on the healing of exposed dental pulp after pulp capping: An experimental study in a dog model

BACKGROUND

This study investigates the influence of insulin on pulp tissue healing after pulp capping in diabetic dogs.

METHODS

Diabetes mellitus was induced in four dogs, and their blood glucose levels were adjusted by insulin to normoglycemic level in two dogs (normoglycemic group) and to hyperglycemic level in two dogs (hyperglycemic group). Class V buccal cavities were performed in 15 teeth in each diabetic dog and two normal dogs (control group). The three groups (30 teeth each) were divided according to the capping materials into three subgroups (10 teeth each) including: subgroup A - mineral trioxide aggregate (MTA), subgroup B - bioaggregate (BA), and subgroup C - calcium hydroxide (Ca(OH)₂ ). Each subgroup was divided into two subdivisions according to the evaluation period, subdivision 1: 1 month and subdivision 2: 2 months. Qualitative and quantitative evaluations of the inflammation and dentine bridge formation were assessed histologically.

RESULTS

The hyperglycemic diabetic group exhibited significant higher inflammatory cell count and scores and lower dentine bridge thickness than those of the normoglycemic diabetic and control groups (P < .05). There were no significant differences in these parameters between the normoglycemic diabetic and control groups (P > .05).

CONCLUSION

Insulin has favourable effects on the pulp tissue healing after pulp capping in diabetic dogs.

Marginal adaptation, solubility and biocompatibility of TheraCal LC compared with MTA-angelus and biodentine as a furcation perforation repair material

BACKGROUND

This study evaluated the marginal adaptation, solubility and biocompatibility of TheraCal LC compared with mineral trioxide aggregate (MTA-Angelus) and Biodentine when used as a furcation perforation repair material.

METHODS

The marginal adaptation was assessed by scanning electronic microscope and presence of any gap between the dentin surface and filling material in each quadrant of the sample was analyzed at 1000 X magnification. The solubility was measured after one week by the ISO standard method. Biocompatibility was evaluated by the inflammatory response and radiography after one month and three months of repair of experimental furcation perforations in dog's teeth.

RESULTS

There were significant differences in the marginal adaptation, solubility and biocompatibility of the tested materials (P < 0.05). TheraCal LC showed the highest frequency distribution of gap presence that was followed by the MTA-Angelus then Biodentine. The least soluble material after one week was TheraCal LC that was followed by the MTA-Angelus and Biodentine. After one month and three months, TheraCal LC showed the highest inflammatory response and highest frequency distribution of radiolucency that was followed by the Biodentine then MTA-Angelus.

CONCLUSION

Unlike Biodentine, TheraCal LC is incapable of alternating the MTA in furcation perforation repair due to its poor biocompatibility and poor marginal adaptation.