ABSTRACT
Numerous dental researchers have described how the edentulous ridge resorbs, as a result of remodeling processes taking place after extraction. Usually, reimplanted teeth are ankylosed and subsequently resorbed such that the crown eventually loosens. When using implants of polymethylmethacrylate, there was definitely less bone loss over the implants than over the control site in the same patient. Tooth root substitution by apatite implants seems to be a simple method of preventing the ridge to resorb after extraction of teeth. Permucosal implants are meant to transmit occlusal loads to the alveolar bone, and have therefore the primary task to avoid loads on the mucoperiosteum. Exposure of implants, occurring with a frequency of 3 to 4% per year under loaded full lower dentures, could be treated by renewed primary closure. Dehiscencies leading to exposure, probably can be avoided when the implants are not placed at or just below the apical part of the socket crest, but 1 to 2 mm lower.
