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

OBJECTIVE: 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. MATERIAL AND METHODS: All mandibular premolars and first molars were extracted bilaterally in six dogs. After 3 months, 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 3 months, ligatures were placed in the sulcus around the implants to induce an experimental peri-implantitis and plaque accumulation was allowed. After 3 months, 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 5 months, biopsies were obtained. Marginal bone levels were compared between x-rays and histological assessments. RESULTS: 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 ± 1.71 mm in the control group, and 3.65 ± 1.76 mm in the plaque group (p = 0.463). The additional marginal bone loss after 5 months from surgical treatment was 0.67 ± 0.67 mm (UnicCa, 0.48 ± 1.06 mm and SLActive, 0.79 ± 2.10 mm) and 3.11 ± 1.38 mm (UnicCa, 2.67 ± 1.87 mm and SLActive, 3.94 ± 2.11 mm) for the control and plaque groups, respectively (p = 0.028). CONCLUSIONS: The lack of plaque control after the surgical treatment of the peri-implantitis strongly influenced the marginal bone loss.

Peri-implantitis at implants with different diameters: a pilot study in dogs.

AIM: To evaluate the progression of an induced peri-implantitis at implants with different diameters and the outcome of a corrective surgical debridement. METHODS: Three months after the extraction of the mandibular premolars and first molars in six dogs, non-submerged narrow implants (3.3 mm in diameter) or standard implants (3.8 mm and 4.1 mm) were installed in the molar regions, bilaterally. After 3 months, peri-implantitis lesions were induced with ligatures and plaque accumulation for 3 months. Plaque accumulation was allowed for a further month after ligatures removal. A surgical mechanical decontamination of the surfaces was subsequently performed using gauzes soaked in saline and irrigation. Five months after, biopsies were retrieved and histological slides prepared. X-rays were taken at treatment and 5 months after. RESULTS: Fourth months after peri-implantitis induction, 2.2 ± 1.0 mm at the standard implants and 3.2 ± 0.4 mm at the narrow implants were observed. Five months after treatment, a mean gain of marginal bone of 0.5 ± 0.6 mm was obtained at the standard implants and of 0.9 ± 0.4 at the narrow implants (p = 0.249). The vertical and horizontal defects were found partially closed. At the histological analysis, the coronal level of osseointegration after 5 months of healing was at 2.1 ± 0.8 mm at the standard implants, and 2.8 ± 0.3 mm at narrow implants (p = 0.116). CONCLUSIONS: In conclusion, the narrow implants showed a tendency of a faster progression of the induced peri-implantitis compared to standard implants. The implant diameter did not influence the outcome of a surgical treatment of an induced peri-implantitis.

Aftas bucales

Se presenta un estudio de las diferencias etiológicas, histopatológicas y anatomoclínicas entre estomatitis aftosa y la periadenitis mucosa necrótica recurrente realizando una revisión de la terapéutica en ambas lesiones. Se concluye que ambas entidades constituyen alteraciones nosológicas perfectamente definidas que pueden diferenciarse por el examen histológico y por el examen clínico. Destacamos la ausencia de cicatriz en la curación de las aftas no así, en la periadenitis. El tratamiento de ambas lesiones es similar faltando aún estudios más profundos para encontrar una terapéutica más científica y racional en ambas lesiones. Finalmente se muestran lesiones bucales características de estas dos entidades(AU)