The effect of glutaraldehyde pulpotomy treatment on pulpal enzymes

The enzymes lactate dehydrogenase (LD), succinate dehydrogenase (SD), alkaline phosphatase (AP), and glucose-6-phosphate dehydrogenase (G-6-PD) were evaluated at specific locations in pulp tissue following glutaraldehyde pulpotomies. Pulpotomies were performed on maxillary first molars in 40 rats after sacrifice at times 0, 24 hr, seven days, or one month, and experimental teeth were treated with 6% buffered glutaraldehyde. Teeth were prepared for frozen sectioning and the sections were subjected to incubation media to detect each enzyme. Significant differences were found regarding the location of staining and the time intervals at which stain was present or absent. Staining for LD and AP was the most intense throughout the four observation time periods, though staining for these enzymes as well as for G-6-PD had begun to diminish by day seven in the coronal thirds. Staining was completely absent in the coronal thirds at one month but remained in the middle and apical thirds throughout one month. SD was the only enzyme that was totally absent in the coronal third at seven days and totally absent in the middle third at one month. These findings suggest that LD, AP, and the biochemical mechanisms that they represent remain active longer than SD and G-6-PD following exposure to glutaraldehyde. This information is important in identifying mechanisms that are important for repair, healing, and recovery following pulpal injury.