Primate Pulpal Healing after Exposure and TheraCal Application

Abstract

Aim: The purpose of this in vivo study was to compare the effectiveness of a new light cured resin based dicalcium/tricalcium silicate pulp capping material (TheraCal LC, Bisco), pure Portland cement, resin based calcium hydroxide or glass ionomer in the healing of bacterially contaminated primate pulps. Study design: The experiment required four primates each having 12 teeth prepared with buccal penetrations into the pulpal tissues with an exposure of approximately 1.0 mm. The exposed pulps of the primate teeth were covered with cotton pellets soaked in a bacterial mixture consisting of microorganisms normally found in human pulpal abscesses. After removal of the pellet, hemostasis was obtained and the pulp capping agents applied. The light cured resin based pulp capping material (TheraCal LC) was applied to the pulpal tissue of twelve teeth with a needle tip syringe and light cured for 15 seconds. Pure Portland cement mixed with a 2% Chlorhexidine solution was placed on the exposed pulpal tissues of another twelve teeth. Twelve additional teeth had a base of GIC applied (Triage, Fuji VII GC America) and another twelve had a pulp cap with VLC DYCAL (Dentsply), a light cured calcium hydroxide resin based material. The pulp capping bases were then covered with a RMGI (Fuji II LC GC America). The tissue samples were collected at 4 weeks. The samples were deminerilized, sectioned, stained and histologically graded. Results: There were no statistically significant differences between the groups in regard to pulpal inflammation (H= 0.679, P=1.00). However, both the Portland cement and light cured TheraCal LC groups had significantly more frequent hard tissue bridge formation at 28 days than the GIC and VLC Dycal groups (H= 11.989, P=0.009). The measured thickness of the hard tissue bridges with the pure Portland and light cured TheraCal LC groups were statistically greater than that of the other two groups (H= 15.849, P=0.002). In addition, the occurrence of pulpal necrosis was greater with the GIC group than the others. Four premolars, one each treated according to the protocols were analyzed with a microCT machine. The premolar treated with the light cured TheraCal LC demonstrated a complete hard tissue bridge. The premolar treated with the GIC did not show a complete hard tissue bridge while the premolar treated with VLC Dycal had an incomplete bridge. The pure Portland with Chlorhexidine mixture created extensive hard tissue bridging. Conclusion: TheraCal LC applied to primate pulps created dentin bridges and mild inflammation acceptable for pulp capping.

Histological evaluation of human pulp capped with light-cured calcium based cements: a randomized controlled clinical trial

“…However one recent study in 2014, done on primates by Cannon et al, found out that TheraCal LC showed better pulpal response after 28 days, when compared with Dycal and glass ionomer cement. 22 Though hydrophobic and hydrophilic resins can be irritant to pulp, a study by Gondolfi et al in 2011, comparing Thercal LC with Dycal and Portland cement, stated that presence of these monomers in TheraCal LC enhanced the calcium release due to hydration. Here the calcium release from TheraCal LC was significantly more than Dycal.…”

“…These attributes have resulted in thick dentinal bridge formation in primates' pulp with TheraCal LC when compared to Dycal and Portland cement, as reported in a study by Cannon et al in 2014. 22 A review on Calcium silicate based cements by Dawood et al in 2015, has elaborated that TheraCal LC has less solubility, less water sorption and better sealability. 25 However, the response of TheraCal LC in our study was not superior to Dycal both in inflammatory response and hard tissue barrier formation.…”

Cytotoxicity and biocompatibility of resin-free and resin-modified direct pulp capping materials: A state-of-the-art review

“…Compared to the resin-containing calcium hydroxide (Ultra-Blend Plus) and resin-modified Glass Ionomer (Vitrebond, 3M, ESPE), the resin-containing calcium silicates (TheraCal LC) presented lower cytopathic effects to cultured pulp cells 36) . In a 4-week in vivo study on primate pulp capped with 4 different materials, both the Portland cement and TheraCal LC groups presented more frequent and thicker hard tissue bridge formation than the GIC and VLC Dycal groups 37) . A 2-year in vivo study demonstrated that TheraCal LC had higher success rate (93.3%) for direct pulp capping than antibacterial adhesive system (Protect Bond, Kuraray) (83.3%) and Glass Ionomer cement (Fuji IX, GC) (66.6%) 38) .…”

Shear bond strength of different dentin substitute restorative materials to dentin of primary teeth

“…These materials aim to encourage the formation of tertiary dentin and remineralization as well as improve the marginal integrity of composite restorations 8,12) . Glassionomer cements (GICs), RMGICs, flowable resin composite, calcium hydroxide (Ca[OH]), adhesive systems and bioactive Biodentine have been utilized as cavity liners 13,14) to provide the stress buffering capacity for reducing the contraction stress and gap formation at the dentin/resin adhesive interface 15) . Dentin substitute/ replacement materials included in this study are: SDR which is intended to be used as a liner under direct class I and II restorations and class II box, Biodentine which is indicated in deep or large carious lesions, deep cervical lesions and pulp capping, MultiCore which is indicated for core build-up of vital and non-vital teeth and Fuji II LC which is indicated as a liner and restoration of class III, V and limited class I cavities and primary teeth.…”