Short Implants - An Alternative to Bone Grafting?

Study on ASTRA TECH Implant System, Short Implants (OsseoSpeed™) Compared to Standard Length Implants (OsseoSpeed™) in Combination With Bone Grafting

The study, with the ASTRA TECH Implant System, is comparing short implants (OsseoSpeed™) to standard length implants (OsseoSpeed™) in combination with bone grafting. The hypothesis is that the use of short implants in posterior maxilla with inadequate bone is as safe and predictable as placing standard length implants in combination with bone augmentation.

This study was designed as an open, prospective, randomized, controlled, multicenter, 5-year follow-up investigation evaluating the outcome of treatment with the OsseoSpeed™ implant 6 mm placed in the posterior maxilla compared to treatment with OsseoSpeed™ implant 11, 13 or 15 mm placed after bone grafting. The study was during the conduct of the study amended to include a 10-year extension cohort.

Inclusion Criteria:

• Provision of informed consent
• Aged 20-75 years at enrolment
• History of edentulism in the study area of at least four months
• In need for 1-4 implants in either side of the posterior maxilla (premolar and molar region)
• Neighboring tooth/teeth to the planned implant/s must have natural root(s) or implant supported restoration, with absence of pathology or excessive bone loss, as judged by the investigator
• Presence of natural tooth/teeth, partial prosthesis and/or implants in the opposite jaw in contact with the planned crown/s
• Deemed by the investigator to have a bone height between 5 and 7 mm and a bone width of a minimum of 6 mm
• Deemed by the investigator as likely to present an initially stable implant situation

Exclusion Criteria:

• Unlikely to be able to comply with study procedures, as judged by the investigator
• Earlier bone graft procedures in the study area
• Uncontrolled pathologic processes in the oral cavity
• Known or suspected current malignancy
• History of radiation therapy in the head and neck region
• History of chemotherapy within 5 years prior to surgery
• Systemic or local disease or condition that could compromise post-operative healing and/or osseointegration
• Uncontrolled diabetes mellitus
• Corticosteroids, iv bisphosphonates or any other medication that could influence post-operative healing and/or osseointegration
• Smoking more than 10 cigarettes/day
• Bruxism
• Present alcohol and/or drug abuse
• Involvement in the planning and conduct of the study (applies to both Astra Tech staff and staff at the study site)
• Previous enrolment in the present study
• Simultaneous participation in another clinical study