Apexification: follow-up after 6-12 years.

Thirty 'apexified' immature permanent anterior teeth treated utilising Ca(OH)2 as root canal dressing assessed clinically and radiographically after greater than 6 less than or equal to 12 years revealed that in 15 teeth bridge remained the same; in 10 consolidated, while in 3 it decreased. Periapical radiolucency reappeared in one case, while in two it was questionable but clinically the teeth were comfortable; these cases were ones showing decrease in bridge consolidation: two teeth had been extracted during this observation period by some dentists because of complaint of discolouration.

Comparative study to evaluate the efficacy of surgical and conservative techniques for apexification in young permanent teeth with open apices.

The Study was conducted to compare and evaluate the effectiveness of surgical and conservative approach for apexification. Twenty-four non-vital permanent maxillary anterior teeth were selected for this study. The teeth selected were having wide apical foramen and definite radiolucent periapical area. Twelve teeth were treated under conservative method and another 12 teeth with surgical method using 'Renew' (A radioopaque calcium Hydroxide paste). The patient were recalled after 1 1/2, 3, 4 and 6 Months. The results of the study indicated that Calcific bridge formation is rapid in teeth treated with conservative technique. However, periapical repair is accelerated in teeth treated by surgical technique, though the results are comparable at the end of 6 months, So the conservative approach is preferred as it saves surgical trauma. In conservative technique, 75% of the teeth showed calcific bridge formation and 100% showed decrease in periapical radiolucent area by 3.56 mm (mean) after 6 months. In surgical technique the radiographic evidence of calcific bridge formation was noticed in 54.51% of teeth after 6 months. However in 100% of teeth there was decrease in periapical radiolucent area by 3.53 mm (mean) after 6 months.

Desmineralización de hidroxiapatita y dentina por EDTA / Demineralizing of hydroxiapatita and dentine by EDTA

La magnitud de la desmineralización por solvatación ácida es casi tan importante como la quelación por EDTA, procesos que ocurren simultáneamente durante el tratamiento con EDTA del diente. Un 45% del mineral disuelto se debe al protón, pero esta solvatación demora más tiempo que la quelación. Al acidificarse el medio, el quelato CaEDTA se disocia. Esto junto con un aumento de la concentración de HPO=4, según el modelo de Van Dijk, haría disminuir la velocidad de desmineralización. Una estimación rápida de las concentraciones de estas especies en el diente ([Ca+2]=10-6M,[HPO=4]=10-3M,[OH-]=10-8M) nos muestra que a pH6 la reacción carece de fuerza motriz y la desmineralización por EDTA se autolimita