[Posterior implant-supported single crowns: a new treatment approach]

Up to the present time, the discussions of single crown restorations with dental implants have been focused primarily on the anterior maxilla or mandible. This clinical case presentation illustrates that it is possible to reconstruct the posterior mandible, and, for the first time, even the subantral augmented maxilla after sinus elevation, with single crowns supported by implants. The presented treatment philosophy imitates natural human dentition. After a single tooth loss, an implant is placed immediately in order to provide functional stimulation of the bone, thereby maintaining the activity of the osteoblasts and keeping the alveole bone is sound condition due to the natural function. After extensive bone augmentation, reconstruction, proper healing time, and precise prosthetic planning of the optimal location of the crowns, implants were placed accordingly and later restored with single crowns in the size of premolars. According to the natural dentition, the author placed one implant per molar root, ie, one implant each for the mesial and distal root of the first molar and possibly the mesial root of the second molar. In all the cases restored, the crown/root ratio was smaller than one. The size of the crown is designed in such a way that the masticatory forces are transmitted axially and vertically via crown into the implant. In 16 clinical cases, none of the 96 single crowns and implants (28 of these in the augmented subantral region of the maxilla), have been lost during 6 months to 3 years of use.