Assessment of titanium release following non-surgical peri-implantitis treatment: A randomized clinical trial.

BACKGROUND: Peri-implantitis is a frequent finding. Initial treatment involves non-surgical debridement of the implant surface. Recent studies have found a correlation between titanium (Ti) particle release and peri-implantitis, yet there is a dearth of information regarding the effect of various non-surgical instrumentation on particle release or peri-implantitis resolution. METHODS: Patients with peri-implantitis were recruited for a randomized, blinded, parallel-group clinical trial. The implants were randomized to treatment composed of Ti curettes ("Mech" group) or implant-specific treatment composed of rotary polymer microbrushes ("Imp" group). Ti release in submucosal peri-implant plaque pre- and 8 weeks posttreatment was assessed as the primary outcome. Peri-implant probing depth, bleeding on probing, and suppuration on probing were evaluated and compared between groups. RESULTS: Thirty-four participants completed treatment; 18 were randomized to the Mech group and 16 to the Imp group. The groups were comparable for Ti levels and probing depths at baseline. A trend was noted for 10-fold greater Ti dissolution in the Mech group posttreatment compared to the Imp group (p = 0.069). The Imp group had a significant reduction in probing depth posttreatment (p = 0.006), while the Mech group reduction was not significant. CONCLUSION: Peri-implantitis treated non-surgically with implant-specific instruments (Imp group) had a significantly greater decrease in probing depth versus the Mech treatment group. This improvement was linked with a trend for less Ti release to the peri-implant plaque by the non-abrasive treatment.

Structural characteristics of periodontal ligaments in the pig model with experimental periodontitis.

To investigate how the structure of Sharpey's fibers in the periodontal ligaments (PDL) were affected by experimental periodontitis in a young pig model, 7 were periodically inoculated with four types of bacteria and a ligature around the last maxillary molar for 8 weeks to induce periodontitis (PG), and 10 served as controls (CG). The harvested molar blocks were sectioned coronally and stained with either hematoxylin & eosin (H&E) or Sirius Red (SR). The H&E-stained images were first reviewed. Then, images of each adjacent SR-stained sections were captured at the region close to the apex of mesial roots under polarizing light microscopy. Sharpey's fiber numbers in each bundle, total bundle numbers, connection of the bundle to the cementum and alveoli, as well as bundle angulations to the molar long axis were quantified in the defined area 500µm apical to the root apex. Compared to CG, PG showed the following features: 15.13% less total bundle number; 17.8% less bundle size; significantly less connected fiber bundles; 9.2% more interrupted fiber bundles; and 3.85% more oriented toward the cervical in the bundle angulation. These results suggest that experimental periodontitis alters the PDL structure, leading to more interruptions of Sharpey's fiber attachments to the cementum.