Decontamination of biofilm-contaminated implant surfaces: An in vitro evaluation

Combining Glycine Powder Air-Polishing and Ultrasonic Scaling for Bone Regeneration Around Infected Dental Implants

OBJECTIVES

In vitro studies were conducted to evaluate the effectiveness of combining glycine powder air-polishing (AP) and ultrasonic scaling (US) in surgical bone reconstructive therapy for peri-implantitis.

MATERIALS AND METHODS

Twenty clinically failed implants and 60 pristine implants were treated in vitro with AP and/or US by using stainless steel, titanium, or carbon fiber tips. Implant surface topography, contaminant distribution, elemental proportion, and composition were analyzed using scanning electron microscopy and energy-dispersive X-ray spectroscopy.

RESULTS

AP effectively removed bacterial plaques but was unable to eliminate calcified deposits involving calculi and bone fragments. Conversely, US exhibited a high capacity for removing calcified deposits but inevitably altered implant surface topography and the atomic percentages of oxygen (O) and titanium (Ti) regardless of the ultrasonic tip used. AP showed minimal effects on the implant surface and even alleviated the adverse effects of US on the surface topography and the atomic percentages of O, Ti, and even carbon. A sequential protocol involving AP followed by US, with a final AP step, effectively removed contaminants from infected implants while minimally affecting the original surface features.

CONCLUSIONS

The combined application of AP and US in surgical peri-implantitis therapy may be a preferred and effective approach for obtaining bone regeneration around infected dental implants.

The Effect of NiTi Brush, Polishing Brush, and Chemical Agent on the Dental Implant Surface Morphology and Cytocompatibility

OBJECTIVES

To in vitro investigate the effect of different implant surface decontamination methods and treatment storing conditions on implant surface morphology and cell viability.

MATERIALS AND METHODS

Titanium disks with a sand-blasted and acid-etched surface (Promote, PRO) were treated with diamond polishing brushes (BRUSH), nickel-titanium brushes (NITI), or phenol and sulfuric acid-gel (GEL). The disks were stored in saline (-S) or left exposed to air overnight (-A). Untreated (PRO) and machined (MACHINED) disks were used as controls. GEL samples were treated for the 60 s, while the operative time was recorded for BRUSH and NITI. The samples were subjected to scanning electron microscopy (SEM), surface roughness measurements, and cell viability (SaOS-2 cells, 7 days) assessment.

RESULTS

The operative time was shorter for NITI than for BRUSH (p = 0.017). The original surface morphology (PRO) was not altered in the GEL group, in contrast with what was observed for BRUSH and NITI. The type of storage did not influence the surface morphology. No significant differences in Sa and Sz were observed among the groups, except for MACHINED, which presented lower Sa values (p < 0.05). Cells were able to proliferate on all surfaces. NITI-S showed significantly higher cell viability compared to all groups (p ≤ 0.001), except for NITI-A and MACHINED. Among the treated groups, only one additional significant difference was found, as NITI-A performed better than GEL-S.

CONCLUSIONS

None of the investigated protocols compromised the cytocompatibility of the titanium dental implant surface. The best results were registered in the NITI group when the samples were stored in saline. Future studies should confirm the effectiveness of the proposed methods in removing bacterial biofilm from contaminated implant surfaces.

The Effect of Peri-Implant Therapy on the Expression of Th17-Related Cytokines in Patients with Peri-Implant Mucositis and Peri-Implantitis: A Prospective Longitudinal Study

Background/Objectives: Cytokines related to the Th17 response have been associated with peri-implant diseases; however, the effect of peri-implant therapy on their modulation remains underexplored. To evaluate the effect of peri-implant therapy on the expression of cytokines related to the Th17 response in the peri-implant crevicular fluid (PICF) (GM-CSF, IFN-γ, IL-1β, IL-4, IL-6, IL-10, IL-12 (p70), IL-17A, IL-21, IL-23, and TNF-α) of partially edentulous patients with peri-implant disease (PID). Methods: Thirty-seven systemically healthy individuals presenting with peri-implant mucositis (PIM) (n = 20) or peri-implantitis (PI) (n = 17) were treated and evaluated at baseline (T0) and three months after therapy (T1). Clinical parameters (probing depth (PD), clinical attachment level (CAL), plaque index, and bleeding on probing index (BoP), were evaluated. The PIM group underwent non-surgical therapy, while the PI group received a surgical approach. PICF was collected with absorbent paper strips and analyzed with a multiplex assay. Results: Eighty-eight implants were treated in 37 patients (56 in the PIM group and 32 in the PI group). After therapy, significant reductions in PD, CAL, plaque index, and BoP were observed in the PIM group (p < 0.05). In the PI group, significant reductions in PD, CAL, and BoP were noted (p < 0.05). The PIM group showed a significant reduction of IL-17A and TNF-α after therapy, while the PI group showed a significant reduction of IL-1β, IL-6, and TNF-α (p < 0.05). Conclusions: The peri-implant therapy for patients with PID reduced the expression of cytokines related to the Th17 response in PICF.

The Effects of Different Hygiene Instrumentations on Titanium Implant Fixture Surfaces

Background and objective Applying different hygiene tools for implant maintenance alters surface configurations, impacting bacterial adhesion on titanium implant surfaces and potentially leading to peri-implant diseases. This study aimed to assess the alterations in surface topography of titanium implant fixtures after utilizing hygiene instruments such as airflow; erbium, chromium-doped: yttrium, scandium, gallium, and garnet (Er, Cr: YSGG) laser; and titanium brush, under scanning electron microscope (SEM) observation. Materials and methods We employed an experimental laboratory study design for this research, involving 20 MegaGen ST titanium implant fixtures (MegaGen Implant Co., Ltd., Seoul, Republic of Korea). These were classified into four groups: untreated/control fixtures (n=5); fixtures treated with airflow using sodium bicarbonate powder (n=5); fixtures treated with an Er, Cr: YSGG laser system at 1.5 W power and a laser pulse of 30 Hz (n=5); and fixtures treated with titanium brush operating between 300 to 1000 rpm (n=5). All fixtures were then rinsed with normal saline, fixed with 2.5% glutaraldehyde, and observed under SEM. Results In the SEM analysis, at 50x magnification, there were no differences between the fixtures. However, at 1000x, 2000x, and especially at 5000x magnification, the control group surfaces appeared to have no obvious change and were quite similar, with clearer surface details. The airflow group exhibited smoother surfaces with less complex and more organized structures. The laser group displayed a more irregular and haphazard structure, revealing a rougher topography. The titanium brush group showed the areas of the implant fixture surfaces appearing smoother and flatter. Conclusions In this SEM study, the titanium brush group yielded the smoothest surfaces and the most favorable overall outcomes, highlighting its efficacy.

Long-term outcomes and prognostic factors of surgical treatment of peri-implantitis - A retrospective study

AIM

To evaluate long-term outcomes and prognostic factors of non-reconstructive surgical treatment of peri-implantitis.

MATERIALS AND METHODS

One hundred forty-nine patients (267 implants) were surgically treated for peri-implantitis and followed for an average of 7.0 (SD: 3.6) years. The primary outcome was implant loss. Additional bone loss and surgical retreatment were secondary outcomes. Patient/implant characteristics, as well as clinical and radiographic parameters collected prior to initial surgery, were evaluated as potential predictors of implant loss. Flexible parametric survival models using restricted cubic spline functions were used; 5- and 10-year predicted rates of implant loss were calculated according to different scenarios.

RESULTS

Fifty-three implants (19.9%) in 35 patients (23.5%) were lost during the observation period. Implant loss occurred after a mean period of 4.4 (SD: 3.0) years and was predicted by implant surface characteristics (modified surface; HR 4.5), implant length (HR 0.8 by mm), suppuration at baseline (HR 2.7) and disease severity (baseline bone loss: HR 1.2 by mm). Estimates of 5- and 10-year implant loss ranged from 1% (best prognostic scenario; initial bone loss <40% of implant length, turned implant surface and absence of suppuration on probing (SoP)) to 63% (worst prognostic scenario; initial bone loss ≥60% of implant length, modified implant surface and SoP) and from 3% to 89%, respectively. Surgical retreatment was performed at 65 implants (24.3%) in 36 patients (24.2%) after a mean time period of 4.5 (3.1) years. In all, 59.5% of implants showed additional bone loss, were surgically retreated or lost.

CONCLUSIONS

Recurrence of disease is common following surgical treatment of peri-implantitis. The strongest predictor for implant loss was implant surface characteristics. Implant length as well as suppuration and disease severity at baseline were also relevant factors.