The Role of Immediate Provisional Restorations on Bone Level Implants

Not Applicable

Completed

Conditions: Jaw, Edentulous, Partially

Interventions: Device: Straumann® Bone Level SLActive Implant (4.1mm diameter)

Registration Number: NCT00906165

Lead Sponsor: Institut Straumann AG

Brief Summary: The study is designed to evaluate the clinical and radiographic outcomes of Straumann® Bone Level Implant SLActive placed in healed alveolar ridge (at least 8 weeks post extraction) and immediately provisionalised versus the same type of implants placed in healed alveolar ridge but not provisionalised. In both cases the implants will be loaded at 16 weeks (final restorations). The outcomes will be evaluated over a 2-year period.

Detailed Description: This is a prospective, randomised, controlled, single blind, and single center study. The total study duration for each patient should be 24 months.

Straumann Bone Level Ø 4.1 mm SLActive implants will be placed for single tooth replacement, followed by either immediate provisional prosthetic loading or no provisionalised. The final prosthetic loading is made at 16 weeks after implant loading. The implant length will be selected according to the clinical indication of the site based on previous radiographic evaluation.

In total 11 visits per patient are scheduled in this study. Bone level changes, implant success and survival rate, soft tissue changes, aesthetic outcome and adverse events (AEs) will be assessed.

The study devices are CE- (Conformité Européenne, meaning European Conformity) marked products.

One center in the United Kingdom will participate.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 28

Inclusion Criteria

General inclusion criteria
- Males and females, age 18 to 75 years of age (the subjects should be legally able to give informed consent to the procedure; age limitation is also present to avoid inclusion of subjects with incomplete cranio-facial growth).
- Absence of relevant medical conditions. Patients with contributing medical history in which any elective oral surgical intervention would be contraindicated should be excluded. In particular patients with uncontrolled or poorly controlled diabetes, or unstable or life threatening conditions should be excluded.
- Absence of uncontrolled or untreated periodontal disease.
- Absence of untreated caries lesions.
- Patient in good medical and psychological health as documented by self assessment
- Patient's availability for follow-up according to the protocol.
Local inclusion criteria
- A single tooth replacement is required in the incisor, canine, pre-molar and first molar region. Multiple-implant restorations (non adjacent to the test implant) can be performed during the study (not to be included as test implants).
- at least 8 weeks post extraction where the soft tissues of the socket have healed
- Presence of at least one adjacent tooth
- Presence of adequate native bone to achieve primary stability

Exclusion Criteria

General exclusion criteria
- Patients who have any known diseases (not including controlled diabetes mellitus), infections or recent surgical procedures within 30 days of study initiation.
- Female patients who are pregnant or lactating or of child bearing potential not using acceptable methods of birth control (hormonal, barriers or abstinence).
- Patients who are on chronic treatment (i.e., two weeks or more) with any medication known to affect oral status (e.g., phenytoin, dihydropyridine, calcium antagonists, cyclosporine) within one month of baseline visit.
- Patients who are on concomitant anticoagulant therapy of warfarin (coumadine), clopidogrel, ticlopidine or once daily aspirin of more than 81 mg.
- Patients who knowingly have HIV or Hepatitis.
- Physical handicaps that would interfere with the ability to perform adequate oral hygiene.
- Patients who have undergone administration of any investigational drug within 30 days of study initiation.
- Alcoholism or chronically drug abuse causing systemic compromisation.
- Patients who are heavy smokers (>10/cigarettes per day).
- Patients suffering from a known psychological disorder.
- Patients who have limited mental capacity or language skills such that study information cannot be understood, informed consent cannot be obtained or simple instructions cannot be followed.
- Exclude patients with BOP > 30% at the completion of the pre-treatment phase.
Local exclusion criteria
- Exclude experimental sites with inadequate bone availability where initial stability of the implant cannot be achieved or extended augmentation procedures and/ or sinus nasal lift are required.
- History of local radiation therapy.
- Presence of severe oral lesions.
- Severe bruxism or clenching habits
- Patients with lack of posterior occlusion and severely reduced vertical dimension of occlusion
- Patients presenting clinical and radiological signs and symptoms of maxillary sinus disease in the implant area.
- Patients presenting an acute endodontic lesion in the neighboring areas to the experimental procedure (sites with presence of an asymptomatic chronic lesion are eligible)
- Plaque score > 30%

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
2- Delayed Loading	Straumann® Bone Level SLActive Implant (4.1mm diameter)	The Straumann® Bone Level SLActive Implant (4.1mm diameter) will not be immediately provisionalized, instead there will be delayed implant loading. i.e. the patient will receive a removable prosthesis if necessary and the impressions for the final restoration will be taken 12-14 weeks after implant installation. At 16 weeks, the final prosthetic reconstruction will be performed according to the standard procedure for single crown restoration.
1- Immediately provisionalized	Straumann® Bone Level SLActive Implant (4.1mm diameter)	The Straumann® Bone Level SLActive Implant (4.1mm diameter) will be immediately provisionalized upon placement, i.e. impressions will be taken directly after implant installation in order to fabricate screw-retained resin crowns within 48 hours after implant placement. At 16 weeks, the final prosthetic reconstruction will be performed according to the standard procedure for single crown restoration.

Primary Outcome Measures

Name	Time	Method
Radiographic Bone Level Change at the Mesial and Distal of the Implants Between Baseline and One Year Post Treatment	between baseline and one year post treatment	The primary parameter derives from the subtraction of mesial and distal bone level linear x-ray measurements at baseline and one year after implant placement. The distance between the alveolar bone at the level of the first radiographic bone contact with the implant surface and the shoulder of the implant will be measured to the closest 0.1mm at the mesial and distal surfaces of all implants, on digitized standardized peri-apical x-rays using an image analysis computer program.

Secondary Outcome Measures

Name	Time	Method
No. of Participants With Complications of the Implant and Implant Overstructure at 24 Months	2 years after implant placement	No of participants with prosthetic related complications and with implant failures are described after 24 months
Number of Participants With Survival Rate of the Implants at 12 and 24 Months	1 year and 2 years after implant placement	The survival rate of the implants is presented as a cumulative survival rate at 1 year and 2 years post-implant placement.
Probing Pocket Depth	Recorded at 16 weeks, 6, 12, and 24 months after implant placement	The Probing Pocket Depth around the implants will be measured using a UNC-15 probe with light probing force (0.2N) at the post-implant time-points specified. Differences between the Outcome Measure time points will be displayed. Baseline is 16 weeks (loading of implants)
Gingival Recessions (REC)	Recorded at 16 weeks, 6, 12 and 24 months after implant placement	The gingival recessions around the implants are recorded at the above-specified timepoints after implant placement, using a UNC-15 probe. Differences between the Outcome Measure time points will be displayed. Baseline is 16 weeks (loading of implants)
Number of Participants With Soft Tissue Changes Assessed by Papilla Fill Index	Recorded at 12 and 24 months after implant placement	Soft tissue changes: mesial and distal gingival papilla dimensions assessed by Papilla Fill Index (PFI, Jemt 1997) and the Pink Aesthetic Score (PES, Furhauser 2005) will be recorded at the post-implant placement timepoints specified above.
Adverse Events	From randomization to 2 years after implant placement	Adverse Events (AE) and Serious Adverse Events (SAE) will be assessed and followed up throughout the study duration
Soft Tissue Changes, Pink Aesthetic Score	Recorded at 12 and 24 months after implant placement	Soft tissue changes: the Pink Aesthetic Score (PES, Furhauser 2005) will be recorded at the post-implant placement timepoints specified above. The PES index includes assessment of seven variables and each variable is measured with a 2, 1, or 0 score with 2 being the best and 0 being the poorest score. Based on its definition the PES is a cumulative score with 14 being the best and 0 the worst.