This prospective randomized study will evaluate the integration success while supporting a prosthesis for short implants placed into maxillary sites having minimal bone height that would otherwise need sinus augmentation. The resources utilized during treatment will be assessed.

Study (null) hypothesis: the overall benefit of using short length implants to avoid sinus augmentation procedures will offset differences in the cumulative implant survival rates observed between treatment groups.

In this randomized study, patients needing restorations in the posterior maxilla will be randomly assigned to the short implant group (test) or the standard length and augmentation group (control). All implants will be placed using a two-stage approach with healing abutments placed at three months and temporary prosthesis at four months following implant and/ or sinus augmentation surgery. Time, materials, and efforts associated with treating test and control cases will be documented to allow an assessment of the costs incurred with each approach.

Inclusion Criteria:

• patients of either sex and any race greater than 18 years of age
• patients with partial edentulism in the posterior maxilla requiring a unilateral implant-supported maxillary prosthesis
• patients with a residual alveolar floor of the sinus between 4 and 6 mm in height, as assessed on intraoral radiographs, and able to receive at least a 4mm wide implant
• patients must be physically able to tolerate conventional surgical and restorative procedures

Exclusion Criteria:

• patients with active infection or severe inflammation in the areas intended for implant placement
• patients with a > 10 cigarettes per day smoking habit
• patients with uncontrolled diabetes or metabolic bone disease
• patient with a history of therapeutic radiation to the head
• patients who are known to be pregnant
• patients with para-functional habits with evidence of severe bruxing or clenching
• patients not able to commit to a 3 year follow-up program

Adverse events are collected and reported from day 1 of the study to present time (entire duration of study).

Adverse event data is collected by patient questioning and visual examination of patient's mouth during each study visit.