Study to Compare Marginal Bone Loss Around Implants From Two Dental Implant Systems.

Study Overview
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Brief Summary
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The purpose of this study is to compare marginal bone level changes between ASTRA TECH Implant System; Fixture ST and Biomet 3i; Osseotite® Implants. Subjects with partial edentulism in the posterior maxilla and/or mandible will be included and a one-stage surgical protocol will be used. Implants will be loaded within 15 weeks from installation. The subjects will be followed for 3 years.

Official Title
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An Open, Randomized Study to Compare Two Dental Implant Systems With Regard to Changes in Marginal Bone Level.

Conditions
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Jaw, Edentulous, Partially

Intervention / Treatment
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* Device: ASTRA TECH Implant System; Fixture ST: Ø 4.5 cm in lengths of 9, 11 and 13 mm.
* Device: 3i Osseotite® implant: Ø 4.0 in lengths of 8.5, 10, 11.5 and 13 mm


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Provision of written informed consent Age 18 - 75 years Partial edentulism, Kennedy class I or II, last natural tooth must be cuspid or first bicuspid Edentulous in the area/s if implant placement for more than 2 months Exclusion Criteria: Untreated caries and/or periodontal disease of residual dentition Need for pre-surgical bone or soft tissue augmentation in the planned implant area/s. Absence of occlusal stability in centric occlusion Any systemic or local disease or condition that would compromise post-operative healing and/or osseointegration Systemic corticosteroids or any other medication that would compromise post-operative healing and/or osseointegration Pregnancy Present alcohol or drug abuse Tobacco smoking during the last 6 months Unable or unwilling to return for follow-up visits for a period of 3 years

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: ASTRA TECH Implant System; Fixture ST<br>Ø 4.5 cm in lengths 9-13 mm | Device: ASTRA TECH Implant System; Fixture ST: Ø 4.5 cm in lengths of 9, 11 and 13 mm.<br> <br> |
| Experimental: Biomet 3i; Osseotite® Implants<br>Ø 4.0 cm in lengths 8.5-13 mm | Device: 3i Osseotite® implant: Ø 4.0 in lengths of 8.5, 10, 11.5 and 13 mm<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Marginal Bone Level Changes | Marginal bone adaptation was expressed 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. Bone adaptation in millimeters at the 3-year follow-up visit were compared to values obtained at Implant placement (baseline). Positive value indicates bone gain and negative value bone loss. | 3 years after implant placement (baseline) |