ABSTRACT
Objetivos: Evaluar la utilidad de un modelo animal mamífero como la cabra, a fin de estudiar biomateriales indicados para protección pulpar directa. Materiales y métodos: Bajo anestesia general, se realizaron exposiciones pulpares en las caras vestibulares de los ocho incisivos inferiores de cuatro (n=4) cabras de raza criolla. En cada animal, 6 (n=6) exposiciones fueron protegidas con un material experimental (ACPc), y las 2 (n=2) restantes, con un material de control a base de MTA (WMTA). En total se realizaron 24 (n=24) protecciones con ACPc y 8 (n=8) con WMTA. Las cabras fueron separadas en dos grupos de dos (n=2) animales cada uno. Bajo anestesia general, los dientes se extrajeron a los 30 (Grupo 1) y 60 días (Grupo 2), se fijaron en formol búffer fosfato al 10% y se procesaron para el estudio histológico de rutina. Los animales no fueron sacrificados. En cada período, se analizaron 12 (n=12) protecciones pulpares con ACPc y 4 (n=4) con WMTA. Resultados: Grupo 1: Once (n=11) pulpas protegidas con ACPc presentaron puente dentinario completo e inflamación crónica remanente. En un caso no hubo puente dentinario y la pulpa estaba crónicamente inflamada. Las 4 (n=4) pulpas protegidas con WMTA presentaron puente dentinario e inflamación crónica. Grupo 2: Las 12 (n=12) pulpas protegidas con ACPc se encontraban normales, con puente dentinario completo, buena irrigación y capa de odontoblastos continua. Las 4 (n=4) pulpas protegidas con WMTA revelaron condiciones similares. Los resultados se analizaron mediante el test de probabilidad exacta de Fischer (P<0,05). Con respecto al factor inflamación, hubo diferencias significativas (P<0,001) entre los resultados obtenidos a 30 y 60 días, pero no hubo diferencias entre ACPc y WMTA (P>0,05) dentro de cada uno de los períodos de observación. En cuanto a la presencia de puente dentinario, no hubo diferencias significativas (P>0,05) entre ACPc y WMTA en ambos períodos de observación. Conclusiones: Los resultados sugieren que la cabra constituye un modelo animal adecuado para los ensayos de protección pulpar directa (AU)
Aim: To evaluate the suitability of the goat as an animal model for the study of biomaterials indicated for direct pulp capping. Materials and methods: Under general anaesthesia, pulp exposures were performed on the buccal surfaces of the eight mandibular incisors of four (n=4) healthy Creole goats. The exposures were capped with two biomaterials developed for PPD. In each animal, 6 (n=6) exposures were capped with an experimental material (ACPc) while for the remaining 2 (n=2) exposures a white MTA (WMTA) was used as the control. A total of 24 (n=24) direct pulp capping with ACPc and 8 (n=8) with WMTA were done. The goats were separated into two groups of two (n=2) animals each. The teeth were extracted after 30 days (Group 1) and 60 days (Group 2) and fixed in 10% phosphate buffered formalin and processed for routine histology. The animals were not euthanized. In each period, 12 (n=12) PPD with ACPc and 4 (n=4) with WMTA were analyzed. Results: Group 1: Eleven (n=11) pulps capped with ACPc showed complete dentin bridges and chronic inflammation. In one case without dentin bridges the pulp was chronically inflamed. The four pulps capped with WMTA revealed the presence of dentin bridges and chronic inflammation. Group 2: Twelve pulps protected with ACPc showed a complete dentin bridges. In addition, well irrigated and healthy pulp tissues along with a continuous odontoblast palisade were observed. The four pulps capped with WMTA revealed similar features. In cases showing dentin bridges, a few numbers of empty spaces as well as odontoblast like cell inclusions were detected. The results were analyzed by the Fisher's exact test (P<0.05). With respect to the inflammation factor there were significant differences between the 30 and 60-day observation periods (P<0.001), but no differences were observed between ACPc and WMTA (P>0.05) within each of the observation periods. When the presence or absence of a dentin bridges was analyzed, no significant differences (P>0.05) were found between materials at each observation period. Conclusions: The results suggest that the goat seems to be an appropriate animal model for direct pulp capping evaluation (AU)