Short (5 and 7 mm long) porous implant in the posterior atrophic mandible: a 5-year report of a prospective study.

PURPOSE

The aim of this ongoing prospective study was to determine the 5-year survival rate of short porous implants in the posterior atrophic mandible.

MATERIALS AND METHODS

In 40 partially edentulous patients, 55 short porous implants were placed. The implants used were of two lengths (5 and 7 mm) and two different diameters (4.1 and 5 mm) and were chosen according to the available crestal height and width. The unloaded healing period was 4 months. Twenty-one implants were restored with single crowns, 32 were splinted to the adjacent implant, 2 were used with an overdenture and were followed for 5 years. Outcome measures were prosthesis failures, implant failures and complications.

RESULTS

No patients dropped out. Nine implants were removed: 1 implant at uncovering and 8 after prosthetic loading. Eight patients lost 1 implant and 1 patient lost 2 implants. Four crowns failed. No complications occurred during the healing period. In 2 patients severe peri-implantitis occurred after loading and the implants had to be removed. At the end of the follow-up period the survival rate was 84% at implant level and 80% at patient level.

CONCLUSIONS

The use of short porous implants showed an acceptable clinical outcome in the treatment of the posterior mandible in this interim 5-year report. These preliminary results must be confirmed by longer follow-ups.