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

• Marginal bone adaption [ Time Frame: after 24 months ] [ Designated as safety issue: No ]
  Marginal bone adaptation will be assessed clinically as probing depth on the lingual aspect of insertion. In addition marginal bone adaption will be followed as the distance from the implant reference point to the most coronal bone-to-implant contact on the mesial and distal side of the implant on intraoral radiographs with paralleling technique. Periapical radiographs will be taken pre- and postoperatively at 24 months follow-up visit. A change in marginal bone will be recorded as positive or negative shift compared to the baseline (preoperatively measured bone height).
• Pinc aesthetic parameter [ Time Frame: after 24 months ] [ Designated as safety issue: No ]
  Pinc aesthetic score evaluation as previously described by Fürhauser and measurement of width of keratinized mucosa and clinical crone length. Data evaluation will be a negative or positive shift compared to the preoperatively evaluated data.
• periodontal parameter [ Time Frame: after 24 months ] [ Designated as safety issue: No ]
  Clinical evaluation of of probing depth in mm (mesial, distal, oral and vestibular), bleeding on probing and Plaque Index as described by Sillness and Löe. Data evaluation will be a negative or positive shift compared to the preoperatively evaluated data.
• Detection and description of implant related complications and other adverse and serious adverse events [ Time Frame: over the study period (24 months) ] [ Designated as safety issue: Yes ]

  Complications are characterized by any failure (mechanical or other) of the implant and/or the prosthetic restoration, as well as the treatment of such failures and will be recorded. The following complications must be reported to the Principal Investigator within 4 working days:

  • Failed osseointegration
  • Lost osseointegration
  • Fixture fracture Adverse events and serious adverse events detection and reporting following GCP-ICH

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.

Patients with tooth loss in the aesthetic zone or in the distal mandible with socket like atrophy. The antagonists should be natural teeth or a fixed prosthesis.

• Inclined Atrophy of the Distal Mandible
• Socket Like Atrophy of the Aesthetic Zone

• Distal region
  Patients with loss of tooth in the premolar and molar region of the atrophied mandible
• aesthetic zone
  Patients with loss of tooth within the aesthetic zone (canine to canine)

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