Short dental implants as a treatment option: results from an observational study in a single private practice

The purpose was to evaluate clinical outcome of short (6- and 8-mm) dental implants placed in sites with low bone availability (7 to 11 mm) in a single private practice and to compare their survival with that of longer implants.

Implants were placed by a single private practitioner in a variety of clinical indications. Exclusion criteria included uncontrolled diabetes mellitus, alcoholism, and systemic immune disorders. Clinical data relating to implant placement and follow-up appointments, including adverse events, were entered into an electronic database. Two-year survival rates were calculated and life table analyses undertaken for implants measuring 6, 8, and 10 to 16 mm.

A total of 630 Straumann implants were placed in 264 patients between April 1994 and December 2003. Of these, 35 implants were 6 mm long, 141 were 8 mm long, and 454 were 10 to 16 mm long. Maximum follow-up was 64.6 months, 83.7 months, and 102 months for implants measuring 6 mm, 8 mm, and 10 to 16 mm, respectively. Two-year survival rates were 94.3%, 99.3%, and 97.4% for 6-mm, 8-mm, and 10- to 16-mm implants, respectively.

The results indicated that the 2-year outcome for 6-mm and 8-mm implants was comparable to that for longer (10- to 16-mm) implants in this patient population.

In this study, short (6- or 8-mm) implants were used with good reliability in patients with limited bone availability, without the need for ridge augmentation. Shorter implant length was not associated with reduced survival at 2 years, compared with longer implants.