Impact of the outcome of guided bone regeneration in dehiscence-type defects on the long-term stability of peri-implant health: clinical observations at 4 years

Objectives: To investigate the impact of residual defect height (RDH) following guided bone regeneration (GBR) in dehiscence‐type defects on the long‐term stability of peri‐implant health after a period of 4 years. Material and methods: The RDH values in dehiscence‐type defects at titanium implants were clinically assessed after 4 months of submerged healing following augmentation using a natural bone mineral (NBM) and a randomized application of either a cross‐linked‐ (VN) or a native collagen membrane (BG) (n=12 patients each). The RDH values were classified as absent (0 mm, control; n=8), minimal (1 mm, test 1; n=8), or advanced (>1 mm, test 2; n=8). Clinical parameters (i.e. bleeding on probing BOP], probing pocket depth PD], mucosal recession MR]) were recorded (mesio‐, mid‐, and disto‐buccal aspects) at 4 years after prosthesis installation. Results: The mean PD (2.9±0.7, 2.8±0.7, 2.7±0.8 mm) values at 4 years were comparable in all the groups investigated. The mean MR values tended to be increased in both the test groups (0.5±0.7, 0.4±0.6 mm, respectively), when compared with the control group (0.2±0.3 mm) (P>0.05, respectively). The mean BOP values were also increased in both the test groups (45.8±30.5%, 54.1±24.8%, respectively), even reaching statistical significance when comparing test 2 and control (29.1±21.3%) groups (P=0.02). Conclusion: The present study indicated that (i) implants exhibiting RDH values >1 mm are at a higher risk of developing peri‐implant disease and (ii) positive RDH values may be associated with an increase in MR and may therefore compromise the overall esthetic outcome of implant therapy. To cite this article:
Schwarz F, Sahm N, Becker J. Impact of the outcome of guided bone regeneration in dehiscence‐type defects on the long‐term stability of peri‐implant health: clinical observations at 4 years. Clin. Oral Impl. Res 23 , 2012; 191–196.
doi: 10.1111/j.1600‐0501.2011.02214.x