PEERS Multicenter Osseospeed TM TX Profile Implant: German Astra Soft Tissue (GAST) Maintenance Study

The open, prospective, non-controlled observational study is designed to provide information on the short-, medium- and long-term clinical performance of the Astra Tech OsseospeedTM implant surface in combination with a special implant design. The study will provide information on implant survival and soft tissue and bone maintenance as clinical performance of the OsseoSpeedTM TX Profile Implant in the aesthetic zone or the posterior mandible with socket like atrophy.

Within the new OsseoSpeedTM TX Profile Implant from Astra Tech a special surface modification treated with diluted hydrofluoric acid is combined with an inclined implant-abutment interface to support soft tissue and marginal bone maintenance in the aesthetic zone or the socket like atrophy in the mandible. Pre-clinical studies of the OsseospeedTM modification support improvement in osseointegration. Both aspects are of special clinical interest in critical situations e.g. reduced bone quantity and quality or in case of socket atrophy with loss of the papillae. The outcome variables of interest are implant survival and the marginal bone and soft tissue response for clinical evaluation of the OsseoSpeedTM TX Profile Implant from Astra Tech. In contrast to the original treatment protocol with a healing period of 3 and 6 months for maxilla and mandible, respectively, the healing period is reduced to 3 months following the recent literature with equal clinical results. Within the present study implants will heal in a transgingival mode and loaded after a healing period of 3 months. For special indications in the aesthetic zone the implants may optionally be loaded following an early loading protocol, which comprehend temporary loading within 48h after implant insertion. Overall implant survival rates are high. However, for implants placed immediately after tooth extraction in the esthetic zone or in the socket like atrophied mandible survival rates are lower. The special physiology of bone resorption in the aesthetic zone exhibit high requirements for soft tissue and bone maintenance for good clinical long term results. Differences in pattern of marginal bone response have been described for different implant systems. The extend of bone loss as also the pattern of remodeling as reaction to OsseospeedTM surface and the special shape of the OsseoSpeedTM TX Profile Implant will be investigated within the present study.

Eligibility Criteria:
Inclusion Criteria:

* loss of tooth aesthetic zone (a maximum of 4 implants)
* loss of tooth at the distal mandible (distal canine) (a maximum of 4 implants)
* presence of inclined alveolar ridge profile
* antagonists are natural teeth or fixed prosthesis

Exclusion Criteria:

* \< 18 years
* Tumour or irradiation
* bisphosphonate or cortisone intake
* Diabetes mellitus
* Mental illness or disorder with affection of compliance
* Consumption of \> 20 cigarettes/day
* Bruxism
* Acute Mucosal infection or illness (e.g. acute Parodontitis, Pemphigus, Lichen)
* Relation of Crown to Implant ratio of \> 1
* No clinical primary stability of the implant after insertion