Comparison of Synthetic Bone Substitute and a Bovine-derived Xenograft in Horizontal Bone Augmentation

The objective of the study is to test the efficacy on bone formation of Straumann Bone Ceramic as a grafting material applied in buccal bone dehiscences on simultaneously placed oral implants.

This is a randomized, controlled, split mouth, prospective, single centre study. The total study duration for each patient should be 76 weeks +/-18 months.

In total 8 visits per patient are scheduled in this study.

The study devices Straumann Bone Ceramic and Bio-Oss are CE-marked, and approved by the FDA. The products are used within the indication.

One center in Beligum will participate.

Eligibility Criteria:
Inclusion Criteria:

* Males and females, 18 years to 80 years of age
* At least two missing teeth up to full edentulous arches.
* Desiring implant supported restorations.
* Both study implants should have a self-containing (2-wall) buccal dehiscence defect after oral implant placement (at least 3.0 mm / max. 5.0 mm defect in apico-coronal aspect to be measured from the boarder of the rough surface of the oral implant to the bottom of the defect).
* At least 4mm of the implant, measured from the apical end to the lowest margin of the bone level, should be covered with bone.
* Sufficient bone volume such that both oral implants will not encroach on vital structures and primary stability of the oral implant can be achieved;
* Patients must be committed to the study and must sign informed consent.
* Patient in good general health as documented by self assessment;
* Full mouth plaque score of \<20%;

Exclusion Criteria:

* Any systemic medical condition that could interfere with the surgical procedure or planned treatment;
* Current pregnancy or breast feeding/ lactating at the time of recruitment;
* Physical handicaps that would interfere with the ability to perform adequate oral hygiene;
* Alcoholism or chronically drug abuse causing systemic compromise.
* Patients who smoke more than 20 cigarettes per day.
* Conditions or circumstances, in the opinion of the investigator, which could represent a general contra-indication for surgical procedure or would prevent completion of study participation or interfere with analysis of study results, such as history of non-compliance, or unreliability
* Lack of primary stability of 1 or both implant(s) at surgery, measured by hand testing. In this instance the patient must be withdrawn and treated accordingly.
* Mucosal diseases such as erosive lichen planus
* History of local radiation therapy.
* Presence of osseous pathologies.
* Presence of oral lesions (such as ulceration, malignancy)
* Severe bruxing or clenching habits.
* Local inflammation, including untreated periodontitis.
* Bone surgery at the implant site(s) (bone grafts, guided tissue regeneration techniques for bone enhancement) prior to implant placement unless performed more than 6 months prior to implant placement.
* Patients presenting clinical and radiological signs and symptoms of maxillary sinus disease.
* Existing teeth in the residual dentition with untreated endodontic pathologies.
* Patients with inadequate oral hygiene or unmotivated for adequate home care