Abstract:

Objective

This clinical study was to evaluated implant ceramic abutments made of aluminum oxide or zirconium oxide，provided by Brånemark and Replace implant systems， with respect to their mechanical properties and peri-implant tissue reaction over time.

Methods

Twenty-three patients with 35 single-tooth implant-support ceramic crowns were included.All-ceramic （IPSEmpress2） crowns were cemented with composite cement. Restorations were evaluated for esthetic outcomes as well as technical problems such as fracture of abutment or crown and loosening of abutment screw or crown during observation period of 12 to 48 months after functional loading.Simplified Gingival Indices were recorded at implants， peri-implant bone levels were radio-graphically determined at the 2 week and 1-year examination.

Results

All but 4 of the 23 patients kept in good function during the observation period.The median observation period for the restorations was 21 months. Crown loosening was reported for 2 restorations at 1 week and 2-year， respectively. Crown fracture was recorded for 1 restoration one week after loading. One abutment made of aluminum oxide fractured after 2-year loading. Mean marginal bone loss was measured （1.2±0.5）mm after 1 year loading. Healthy conditions of the peri-implant mucosa in relation to abutment／crown were maintained with mean Gingival Index measured 0.6±0.2 after 1-year loading. Patients were satisfied with the final esthetic outcomes.

Conclusions

The results demonstrated both alumina and zirconia abutments provided by Brånemark and Replace implant systems offered sufficient stability to support esthetic implantsupported single-tooth restorations in anterior region. The soft and hard tissue reaction toward both ceramic abutments was favorable.

Key words: Implant prosthesis, Ceramic abutment, Alumina, Zirconia