A Study to Treat Patients With Edentulous Mandibles With Two Straumann 3.3mm Diameter Bone Level Implants

Inclusion Criteria

• Subjects must have voluntarily signed the informed consent form
• Males and females must be 18 years of age.
• Patients must present with an edentulous mandible at the time of surgery.
• The last tooth or teeth in the mandible must have been extracted or lost more than 8 weeks before the date of first stage surgery.
• The opposing dentition must be edentulous with a denture (implant borne or conventional) or natural or restored teeth
• Adequate bone height of at least 9 mm above vital structures (because the minimal available implant lengths is 8mm) in the intraforaminal region. Available bone width should be in such way that 3.3 mm implants can be placed without the use of concurrent bone augmentation techniques. Harvested bone from the drilling sites may be used to cover minor dehiscence defects.
• Patients must be committed to participate in the study for three years of follow-up examinations

Exclusion Criteria

• Medical conditions requiring prolonged use of steroids
• History of leukocyte dysfunction and deficiencies
• Patients with sever hemophilia
• History of head and neck radiation or chemotherapy
• Patients with history of renal failure
• The application of bisphosphonate medication
• History of uncontrolled endocrine disorders
• Physical handicaps that would interfere with the ability to perform adequate oral hygiene
• Use of any investigational drug or device within the 30-day period immediately prior to implant surgery on study day 0.
• Alcoholism or drug abuse
• Patients with known infection of HIV
• Patients who smoke more than 10 cigarettes per day or cigar equivalents, or who chew tobacco (not greater than 10 cigarette equivalents)
• Fertile females with no adequate method of birth control (contraceptive pill, barrier method, etc.)
• Conditions or circumstances, in the opinion of the investigator, which would prevent completion of study participation or interfere with analysis of study results, such as history of non-compliance, unreliability.