The effect of various fixatives on the extent of the odontoblast process in human dentine.

Unerupted but fully formed human third molar teeth were prepared for ultrastructural examination using three different fixatives; glutaraldehyde, a mixture of glutaraldehyde and p-formaldehyde and a picric acid-formaldehyde solution. These fixatives have reportedly differing rates of penetration of tissue. Odontoblast processes were found to be limited to the inner-third of crown dentine in all teeth, irrespective of the fixative used.