This study consisted of biopsies of teeth and root tips removed after Ca(OH)2 therapy. The teeth were clinically intact or exposed to caries, trauma, and/or iatrogenesis. Following the therapy most of the canal walls were clean, but the canals contained varying amounts of pulp tissues, debris and Ca(OH)2 particles. In one case microrganisms were present in the apical part of the canal, but not beyond the foramen. The Ca(OH)2 therapy was efficient for its purpose.