Effect of lack of plaque control after the surgical treatment of peri-implantitis at surfaces with different characteristics: an experimental study in dogs.

Abstract

The aim of the present study was to evaluate the effect of the induction of peri-implantitis and of plaque accumulation on implants with different surface characteristics after the surgical treatment. All mandibular premolars and first molars were extracted bilaterally in six dogs. After 3months, two non-submerged implants were installed, each with either a hydrophilic sandblasted and acid-etched surface stored in saline solution (SLActive) or an acid-etched and modified with calcium ions surface (UnicCa). After 3months, ligatures were placed in the sulcus around the implants to induce an experimental peri-implantitis and plaque accumulation was allowed. After 3months, ligatures were removed and, after one more month of plaque accumulation, a surgical treatment was performed using gauzes soaked in saline and irrigations. X-rays were taken at this stage. Plaque control maintenance was established at the control sites, while plaque accumulation was allowed at the test sites (plaque sites). After 5months, biopsies were obtained. Marginal bone levels were compared between x-rays and histological assessments. At the time of peri-implantitis treatment, two SLActive implants were lost. At the euthanasia, seven more implants were lost only in the plaque group, one control and six test implants. The calculated mean values of the marginal bone level of the two surfaces at the treatment were 3.65 ± 1.71mm in the control group, and 3.65 ± 1.76mm in the plaque group (p = 0.463). The additional marginal bone loss after 5months from surgical treatment was 0.67 ± 0.67mm (UnicCa, 0.48 ± 1.06mm and SLActive, 0.79 ± 2.10mm) and 3.11 ± 1.38mm (UnicCa, 2.67 ± 1.87mm and SLActive, 3.94 ± 2.11mm) for the control and plaque groups, respectively (p = 0.028). The lack of plaque control after the surgical treatment of the peri-implantitis strongly influenced the marginal bone loss.