Respuesta pulpar al PRO-ROOT (R) MTA, IFABOND (TM), CALCIPAST + I y BIODENTINE (TM)microfiltración en la interfase material - esmalte

Abstract

Introduction Different materials have been used during the last decades on Vital Pulp Therapy (VPT) cases. Most of them produce good outcomes, although they may present some problems. Calcium hydroxide, which has been the most widely used material, presents dental resorption problems and tunnel defects in dentinal bridges; formocresol, the benchmark material according to most published research, is carcinogenic; grey MTA alters the color of the teeth, while white MTA is expensive, difficult to handle, and takes a long time to set. It&apos;s important to choose the best material in terms of cost, color, handling properties, duration setting time. Objectives To determine whether n-hexyl cyanoacrylate (IFABOND¿), Biodentine¿ and Calcium hydroxide with Iodoform (CALCIPAST + I) could act as substitutes for MTA (PRO ROOT¿ MTA) as a VPT material, and whether the success of outcomes with these materials is directly related to the degree of microleakage at their interface with the dental structure. Material and methods Histological study. 1st and 2nd upper molars of 24 Wistar rats had been drilled. As soon as the bleeding control was achieved, the pulpar surface was covered with 4 different materials: MTA, IFABOND¿, CALCIPAST+I y Biodentine¿. After 30 days treatment, the rats were sacrificed; the jaw fragments containing the study molars were separated, fixed, decalcified and embedded in paraffin. The slices were observed under an optical microscope. Microfiltración study. 20 human premolar extracted due to orthodontic reasons were divided randomly in 4 groups with 5 teeth each, creating class I cavities in the occlusal surface. The cavities were filled with the corresponding material to the cavosurface enamel margin, with the exception of the CALCIPAST + I group in which enamel sealing was performed with glass ionomer (Vitrebond¿ Plus). The samples were submerged in destilled water at 37ºC for 24 hours, 500 thermocicles between 5-55ºC were applied, another 24-hour submersion in methylene blue (1%) was conducted before cutting the samples in 2 different sections. The sections were studied using a stereomicroscope. The microfiltración percentage was measured using an imaging analysis software. Results. The molar pulps treated with MTA did not present inflammation (100%;p<0,0005); But pulps treated with CALCIPAST+I presented slight (50%) or moderate (31,25%;p<0,0005); IFABOND¿ and Biodentine¿ did not present inflammation in 87.5%. All samples (100%) in all groups presented pulp vitality; none of the groups showed pulp necrosis. In the CALCIPAST + I group neither dentinal bridges nor reparative dentin were observed in 18.75% of cases (p=0.024); in the other three groups the presence of a dentinal bridge was observed in 100% of samples. Only pulp treated with MTA showed a regular odontoblastic layer in all samples (100%;p<0.0005). CALCIPAST + I produced a regular odontoblastic layer in 50% of cases and irregular layer in 50%. IFABOND¿ and Biodentine¿ generated an irregular odontoblastic layer in 100% of samples (p<0.00l). All samples treated with MTA presented fibrosis (100%;p<0.0005). But only 37.5% of samples treated with IFABOND¿ and Biodentine¿ (p<0.0005).Calcifications appeared in areas other than the dentinal bridge in all groups (p=0.027). No statistically significant differences were found in microfiltration (p=0,390). Conclusions. Although MTA showed the best behavior, pulp responses to the materials assayed in rat molars produced similar outcomes in terms of the histological criteria of inflammation levels and pulp vitality. The regularity or irregularity of the odontoblastic layer did not appear to influence as much the presence of a dentinal bridge as the type of neoformed dentin. Samples treated with IFABOND¿ and Biodentine¿ did not present fibrosis in all molars, a necessary response for hard dental tissue production, and so fewer calcifications were observed in locations other than the site where pulp chamber perforation had been created. Microfiltration into enamel was similar with all the materials assayed (MTA, IFABOND¿, Biodentine¿, CALCIPAST + I with Vitrebond¿ Plus).