Evaluation of the apical closing with Calcium Hydroxide, MTA and PRGF

The objective of this work was to observe the formation of an apicaltop by means of the use of Ca(OH)2, MTA and PRGF placed inimmature teeth of dogs to a single period of observation. Two dogswere used, in which 16 samples were worked. This work was madein two operating times, first to prevent the normal development ofthe apex, causing an injury placing a short portion of cotton withdentobacterian plaque of human during two months. In the secondoperating time the teeth were divided into four groups according tothe materials to prove: 1. Control cleaning of the canal; 2. CalciumHydroxide – Ca(OH)2; 3. Mineral Aggregate Trioxide; 4. Blood PlasmaRich in growth factors (PRGF). Seven months later, the dogs weresacrificed and samples were prepared to be observed in opticalmicroscope. The obtained results were very similar among the samplesof their own group. Control Group: the apex was totally open, withoutrepair. Group of Ca(OH)2: the apex was open but on the way to repair,forming a weave of hard tissue, small centers of inflammatory infiltrate.MTA group: a total closing of the apex was observed, with organized affluent dentine, and thickening of cement in the apical portion. Plasma Rich in Growth Factors Group: apex opened on the way to repair, cement weave or a type of osteocement was present. Within all the canal, collagen fibers and connective tissue weave were observed and some blood vessels. Based on the observed results, they excel two of the used materials, these are the MTA similar to the natural physiology while PRGF by the weave formed within the root canal; nevertheless the Calcium Hydroxide also stimulates the calcified weave apical formation.