Long-term Evaluation of Pulpotomy in Primary Molars Using Mineral Trioxide Aggregate or Formocresol

Purpose. The objective of this study was to assess the effect of mineral trioxide aggregate (MTA) as pulp dressing material following pulpotomy in primary molars with carious pulp exposure and compare them to those of formocresol (FC).

Methods. Of 33 children, primary molars treated via a conventional pulpotomy technique were randomly assigned to the MTA group (33 teeth) or FC group (29 teeth). Clinical and radiographic follow-up ranged between 4 and 74 months. The mean follow-up time was 38 months, with no difference between the groups. Twenty-nine teeth were followed until uneventful shedding (mean=33 months). Failures were detected after a mean period of 16 months (range=4 to 30).

Results. The success rate of pulpotomy was 97% for MTA (1 failure) and 83% for FC (5 failures). Eight teeth presented internal resorption. In 4 of them (2 of each group), progress of the resorption process stopped and the pulp tissue was replaced by a radioopaque calcified tissue. Pulp canal obliteration was observed in 58% of the MTA group and in 52% of the FC group (total=55%).

Conclusions. MTA showed a higher (though not statistically significant) long-term clinical and radiographic success rate than formocresol, and can be recommended as its replacement as, unlike FC, MTA does not induce undesirable responses.