In this study a simple and time–saving method for bleaching of discoloured root‐filled teeth is presented. The method used sodium perborate moistened with water and the access cavity is temporarily sealed with Cavit® between visits. Bleaching was carried out in 95 teeth, with a satisfactory initial result in 90% of the cases. After 3 years of observation, recurrence of discolouration was found in 20% of the teeth seen at follow‐up examination. The method is easy, fast and essentially without complications. It is therefore recommended as an alternative to full crown restoration, assuming the tooth is not too weakened because of large fillings.

Summary. Using an aseptic and standardized endodontic technique, vital pulpectomy was performed on 16 pairs of human permanent maxillary front teeth scheduled for extraction in connection with prosthetic treatment. All the teeth had clinically sound pulps before treatment and 16 teeth were root filled with N2 and the other 16 with Endomethasone. In all cases except two, contralateral teeth were used. After 4–8 months the teeth were extracted and processed for histological examination using light microscopy. Histological examination of the residual pulp demonstrated no statistically significant differences between the two root‐filling materials, concerning inflammation and the frequency of necrosis. The healing reactions, occurrence of fibrous tissue in the residual pulp and hard tissue apposition on the root canal wall, were more pronounced after root filling with N2, than after Endomethasone, but the differences were not statistically significant. Comparing the results with those after vital pulpectomy and root filling with zinc oxide‐eugenol cement, total necrosis of the residual pulp was most frequent after root filling with Endomethasone, less so after zinc oxide‐ eugenol cement and least after root filling with N2, but the differences were not statistically significant. When estimated from the local findings, that is the histological reactions in the residual pulp, no advantages could be observed by using N2 or Endomethasone, and owing to the risk of general side effects, because of the formaldehyde content and the complex composition of the two materials routine use of N2 or Endomethasone cannot be recommended in pulpectomy.

abstract— The aim of the study was to assess the state of the pulp of primary teeth successfully treated by formocresol pulpotomy. Nineteen teeth, all of them with clinically and radiographically successful treatments, were extracted 3–24 months after treatment. The pulpal condition had changed in all the teeth. Inflammatory reaction or necrosis was observed in all teeth. Dentinal resorption followed by apposition of hard tissue were common findings. In the teeth with vital tissue only in the apical area, the tissue had minor or no signs of inflammation. Microorganisms could be demonstrated in the necrotic tissue in one tooth. The wide range of pulpal conditions observed indicated that there was no typical tissue reaction to formocresol even though treatment was clinically successful. The present study confirms that the formocresol method should be regarded only as a means to keep primary teeth with pulp exposures functioning for a limited period of time.

Twenty-two commercially available endodontic posts were examined with regard to stiffness, elastic limit and resistance to fracture. Differences in mechanical properties w^ere explained by differences in width, shape and surface structure.In the selection of an endodontic post, its stability rather than its retention should be of primary clinical concern. Accordingly, the authors advocate the use of endodontic posts that have a cylindrical coronal portion and a conical apical portion.

AEsrRACT -The abilit)' .of six different intermediary base materials to prevent bacterial entrance beneath silicate cement lilliogs was invesdgated in vivo in primary-molars. After an observation period of 1 month, bacteria were found on the pulpal wail in two out of 10 cavities beneath Fluoritec* and four otit of 10 cavides beneath Durelon* solid mixed, De Trey® phosphate cetnent solid or creamy tnixed. Beneath the intennediarj' base materials Dycal®, zinc oxide-eugenol cement,, Dropsin® and Durelon® creamy mixed, no bacteria were found. In cavities filled with silicate cenjent or silver amalgam only, bacteria were observed in nine out of 10 and in five out of 10 cavities, respectively.