The effects of various concentrations and lengths of application of glutaraldehyde on monkey pulp tissue.

This study was designed to examine the histologic response of the dental pulp to the use of selected concentrations of glutaraldehyde applied over various time intervals in pulpotomies performed on monkey teeth. One hundred sixty primary teeth from 8 stump-tail macaque monkeys were divided randomly into 10 groups. One group served as the control and received a zinc oxide and eugenol pulpotomy with no glutaraldehyde. The other 9 groups represented pulpotomies treated with 0.5,1.0, or 2.0% glutaraldehyde applied for 2, 5, or 10 min. The teeth were assigned to observation groups of I day, or 1, 4, or 8 weeks. The monkeys were perfused following termination of the study and the maxillae and mandibulae were removed en bloc. The teeth were examined for histologic changes in the tissues associated with each concentration and time of application. One day after glutaraldehyde treatment, all samples had a zone of fixed pulp tissue at the application interface. At 1 week and continuing through 8 weeks, findings included moderate chronic inflammation progressing to severe inflammation with eventual giant cell formation and internal resorption. The severity of the reactions was related to medicament concentration and time of application with the lower concentrations and shorter application time revealing more severe inflammatory responses. In recent years, formocresol has diminished in popularity as the primary medicament used in vital pulpotomies because of the documented problems of systemic absorption and concurrent systemic toxic effects, 1 locally toxic effects, 2 and less than ideal clinical and histological effectiveness. 3 There is a need to evaluate alternative agents which are both clinically and biologically more successful, and glutaraldehyde has been suggested as an alternative to formocresol in pulpotomy Myers et al. 1978; Pashley et al. 1980; Myers et al. 1981; Myers et al. 1983. 2 Pruhs et al. 1977; Block et al. 1977; Block et al. 1978. Rolling et al. 1976; Magnusson 1978; Rolling and Lambjorg-Hansen 1978. procedures. 4 It is a chemically bifunctional reagent which is a common fixative in electron microscopy (Dawes 1979). Penetration into surrounding periapical tissues is limited primarily by gluteraldehyde’s protein cross-linkage formation, and thus, systemic distribution of glutaraldehyde is limited (Davis et al. 1982). Clinical and/or histologic success has been shown to be comparable if not superior to formocresol in various pulpotomy and endodontic procedures. 5 Although glutaraldehyde was previously used successfully in pulpotomy procedures, there was considerable variability in the application techniques, and they all appear to be empirically determined. Reports of 2-5 % glutaraldehyde solutions were common with application times ranging from 1 to 5 min.6 The purpose of this study was to determine whether the histologic response of pulp tissue would vary significantly according to the concentration of the glutaraldehyde and length of time