Preserving the vital pulp in operative dentistry: 4. Factors influencing successful pulp capping

Outcome of novel pulp capping modalities after full pulpotomy in teeth diagnosed with irreversible pulpitis: A prospective randomized clinical trial

Objective

The study aimed to compare and evaluate the effect of biodentine (BD) alone, BD along with Lyophilised freeze dried platelet rich concentrate (LPC + BD), and BD along with low-level laser therapy (BD + LLLT) after pulpotomy in mature permanent molars with irreversible pulpitis.

Materials and Methods

The study was designed as a randomized, pragmatic, parallel, double-blinded clinical trial registered under the Clinical Trial Registry-India (CTRI/2020/02/023245). 120 permanent molars fulfilling the inclusion and exclusion criteria with symptoms of irreversible pulpitis were randomized after performing pulpotomy into three pulp capping groups: Group 1, BD; Group 2, lyophilized freeze-dried platelet-rich concentrate + BD (LPC + BD); and Group 3, Low level laser therapy + BD Group 3, LLLT + BD. The intergroup comparison was done using one-way analysis of variance followed by the Bonferroni test. The level of significance and confidence interval were 5% and 95%, respectively. Interobserver reliability was measured using Cohen's kappa analysis.

Results

At 1 week, there was a significant difference (P < 0.005) observed in the mean postoperative pain levels between the three groups with Group 1 (BD) exhibiting the highest postoperative pain followed by Group 2 (LPC + BD) and least pain was exhibited by Group 3 (LLLT + BD). A similar pattern was observed regarding the analgesic intake with maximum frequency in Group 1 (BD) and least with Group 3 (LLLT + BD). No significant difference in success rates was reported among the groups.

Conclusion

Pulpotomy as a treatment option for mandibular molars with irreversible pulpitis has an acceptable clinical success rate; however, long-term overall success rate remains questionable. The outcomes of incorporating adjunctive modalities with BD are remarkable and show tremendous potential for continued development and research.

Direct pulp capping of primary molars using a novel fast-setting calcium silicate cement: a randomized clinical trial with 12-month follow-up

Objective: Novel fast-setting calcium silicate cement with fluoride (Protooth) has been developed for potential applications in tooth crowns. The aim of this study was to evaluate the success rate of direct pulp capping in primary molars using two-layer mineral trioxide aggregate (MTA) and overlying glass ionomer cement versus one-layer novel calcium silicate cement with 4 to 10 minutes setting time. Materials and methods: Ninety bilaterally symmetrical primary molars in the same jaw in 45 patients aged 5 to 7 years were included. Exposed pulps following caries removal were randomly capped with one-layer novel calcium silicate cement or two-layer MTA and glass ionomer cement. All cavities were filled with amalgam. Clinical and radiographic evaluations were performed after six and twelve months. 41 patients were available for the evaluations at the end of the 12-month follow-up. Results: The overall success rate of direct pulp capping, in a split-mouth design, using MTA covered with glass ionomer cement or one-layer novel calcium silicate cement after 12 months were 90% (37 out of 41 cases) and 85% (35 out of 41 cases), respectively, without statistically significant differences after 6 and 12 months. Conclusion: Within the limitations of this study, clinical and radiographic evaluations suggested one-layer novel calcium silicate cement would be successfully used in direct pulp capping of primary molars as a practical alternative to two-layer MTA and overlying glass ionomer cement.

Importance of mini-dumbbell specimen to access tensile strength of restored dentine: historical background and the future perspective in dentistry

OBJECTIVES

The development of adhesive resins to dentine enables resin restorations to be more durable. Several bond strength measurement techniques for measuring adhesion have been proposed. A standardised method is needed which produced higher and more consistent bond strength values which allow bond stability and the bonding mechanism to be studied. Our aim was to investigate mainly the adhesives and not the substrate.

DATA SOURCES

This review is based on the literature on an adhesive, 4-META/MMA-TBB resin and conditioners to modify dentine substrates. The latter is a very important topic for developing our understanding of the bonding to dentine. The objective of the review is to explain the efficacy of the mini-dumbbell specimen in measuring the tensile strength of resin to dentine and to analyze the resin to dentine interface. Both the adhesive and the substrate control the quality of hybridized dentine.

CONCLUSIONS

By creating an impermeable acid resistant barrier to both biological and chemical stimuli between the exposed dentine and the restored tooth surface we are able to protect exposed dentine from caries (infection) at the same time as protecting the pulp and preventing toothache. This barrier also helps maintain tooth vitality and for the purposes of this article is termed 'artificial enamel'. Microleakage free restorations are possible through the introduction of this 'impermeable artificial enamel' barrier.

Stem Cell Responses in Tooth Regeneration

Scientific advances in the creation of restorative biomaterials, in vitro cell culture technology, tissue grafting, tissue engineering, molecular biology, and the human genome project provide the basis for the introduction of new technologies into dentistry. This review is intended to facilitate the development of stem cell therapy for use with established therapeutic modalities to restore and regenerate oral tissues. Teeth have been shown to mineralize in response to injury for many decades, but only in recent years has the position of the stem cells been localized around blood vessels. The cells have been identified as myofibroblastoid pericytes. The ability to control the differentiation and proliferation of these cells is being examined to create stem cell therapies that can solve dental problems more effectively than current treatment regimes. Although the problems of introducing these technologies are substantial, the potential benefits to patients and the profession are equally promising - a cure for caries and diseases, a cure for oral cancer, correction of congenital defects, and the regeneration of teeth and tissues to restore oral functions. The purpose of this review is to describe how these new technologies can most usefully be employed in dentistry to enable clinicians to satisfy patient demand for a nondefective dentition.

Comparison of pulp responses following restoration of exposed and non-exposed cavities

OBJECTIVES

The purpose of this study is to compare and contrast differences of pulp responses between non-exposed and exposed cavity preparations in terms of inflammation, frequency of bacterial microleakage, odontoblast and odontoblastoid cell numbers, and tertiary dentine formation.

METHODS

Class V non-exposed cavities (n=161) and exposed cavities (n=161 teeth) were prepared in non-human primate teeth. Cavities were restored with calcium hydroxide [Ca(OH)(2)], resin modified glass ionomer, or resin composite. Following extraction (7-730 days), bacteria were detected with McKays stain and pulp reactions were categorized according to ISO guidelines. Teeth were analyzed histomorphometrically and statistically using analysis of variance tests.

RESULTS

Exposed cavities in comparison with non-exposed cavities were found to have more severe inflammation (p=0.0001), greater quantities of tertiary dentine (p=0.0001), and an increased frequency of bacterial microleakage (p=0.0034). The density of odontoblastoid cells beneath pulp exposed tertiary dentine was found to be 47.8% of odontoblast cell density beneath non-exposed dentine (p=0.0001).

CONCLUSIONS

The restoration of exposed cavity preparations is associated with more traumatic pulp injury and repair responses. Consequently, efforts should be made to minimize iatrogenic dentine removal during cavity preparation and the creation of pulp exposures whenever possible.