The Effect of Implantoplasty on the Fatigue Behavior and Corrosion Resistance in Titanium Dental Implants.

Implantoplasty is a technique increasingly used to remove the biofilm that causes peri-implantitis on dental implants. This technique of mechanization of the titanium surface makes it possible to eliminate bacterial colonies, but it can generate variations in the properties of the implant. These variations, especially those in fatigue resistance and electrochemical corrosion behavior, have not been studied much. In this work, fatigue tests were performed on 60 dental implants without implantoplasty, namely 30 in air and 30 in Hank's solution at 37 °C, and 60 with implatoplasty, namely 30 in air and 30 in Hank's solution at 37 °C, using triaxial tension-compression and torsion stresses simulating human chewing. Mechanical tests were performed with a Bionix servo-hydraulic testing machine and fracture surfaces were studied by scanning electron microcopyElectrochemical corrosion tests were performed on 20 dental implants to determine the corrosion potentials and corrosion intensity for control implants and implantoplasty implants. Studies of titanium ion release to the physiological medium were carried out for each type of dental implants by Inductively Coupled-Plasma Mass Spectrometry at different immersion times at 37 °C. The results show a loss of fatigue caused by the implantoplasty of 30%, observing that the nucleation points of the cracks are in the areas of high deformation in the areas of the implant neck where the mechanization produced in the treatment of the implantoplasty causes an exaltation of fatigue cracks. It has been observed that tests performed in Hank's solution reduce the fatigue life due to the incorporation of hydrogen in the titanium causing the formation of hydrides that embrittle the dental implant. Likewise, the implantoplasty causes a reduction of the corrosion resistance with some pitting on the machined surface. Ion release analyses are slightly higher in the implantoplasted samples but do not show statistically significant differences. It has been observed that the physiological environment reduces the fatigue life of the implants due to the penetration of hydrogen into the titanium forming titanium hydrides which embrittle the implant. These results should be taken into account by clinicians to determine the convenience of performing a treatment such as implantoplasty that reduces the mechanical behavior and increases the chemical degradation of the titanium dental implant.

Peri-implantitis and maxillary sinus membrane thickening: A retrospective cohort study.

OBJECTIVE: The objective of this study is to investigate the association of peri-implantitis (PI) and sinus membrane thickening and to assess the resolution of membrane thickening following intervention (implant removal or peri-implantitis treatment) aimed at arresting PI. MATERIALS AND METHODS: Forty-five patients with 61 implants in the posterior maxillary region were retrospectively included in the study. Twenty-four patients were diagnosed with peri-implantitis (PI) and 21 had peri-implant health (PH). Cone-beam computed tomography (CBCT) scans were evaluated to assess maxillary sinus characteristics, including membrane thickening, sinus occupancy and ostium patency. The CBCT scans taken 6 months after intervention aimed at arresting disease (implant removal or treatment of PI) in the PI group were also appraised and compared to baseline scans. RESULTS: At baseline, all parameters evaluating membrane thickness disorders yielded significant differences between groups (p < .001). Patients with posterior maxillary implants diagnosed with PI were 7× more likely to present membrane thickening compatible with pathology when compared to patients with healthy implants (OR = 7.14; p = .005). Furthermore, the likelihood was 6x greater in implants diagnosed with PI to exhibit moderate membrane thickening (OR = 6.75, p = .001). The patients receiving interventions aimed at arresting PI experienced significant enhancement in all radiographic parameters related to the sinus cavity at the 6-month follow-up (p < .001), though these variations were similarly independent of whether treatment consisted of PI treatment or implant removal. CONCLUSIONS: Maxillary sinus membrane thickening and the permeability/obstruction of the ostium are frequently associated with the presence of PI in posterior implants. Interventions targeting disease resolution effectively reduce membrane thickness to levels compatible with maxillary sinus health.

Clinical outcomes and associated factors in the treatment of peri-implant mucositis, combining mechanical debridement and prosthesis modification: A 30-month follow-up prospective case series.

AIM: To evaluate the clinical outcome and the associated factors of a treatment protocol for peri-implant mucositis. MATERIALS AND METHODS: Patients were evaluated 30 months after a treatment protocol including professional mechanical debridement and modification of the prosthesis contours to improve access for biofilm control. Clinical performance was assessed by means of probing with an electronic pressure-calibrated periodontal probe. The possible impact of implant- and patient-level factors on the changes in peri-implant mucosal inflammation measured with the modified bleeding index (mBI) was evaluated. RESULTS: Twenty patients and 61 implants were included in the analysis. At the final visit, 50% of the patients presented bleeding on probing, with a mean mBI of 0.22 (SD 0.27). The adjusted linear regression model showed a significant association between patient's compliance with supportive care visits (p = .006) and mucosal inflammation. Similarly, at the implant level, modified plaque index (p < .001) and an irregular use of interdental brushes (p = .017) had a significant impact on final mBI. CONCLUSIONS: Prosthesis modification when needed in association with non-surgical treatment may be an important intervention in the treatment of peri-implant mucositis. Compliance with supportive care visits and the regular use of inter-dental brushes were identified as important factors to achieve mucosal inflammation control.

Design and Rationale for a Real-World Prospective, Multicenter Registry of Myocardial Revascularization Failure and Secondary Revascularization: The REVASEC Study.

AIM: To investigate key aspects of the problem of myocardial revascularization failure (MRF) and repeat or secondary myocardial revascularization (SR) in contemporary practice. METHODS: The registry of secondary revascularization (REVASEC) is an investigator-initiated, multicenter, prospective registry enhanced with data monitoring and independent event adjudication (ClinicalTrials.govNCT03349385). It includes patients with prior revascularization referred to coronary angiography for suspected MRF with broad inclusion criteria. The main objectives are to describe the characteristics of patients with prior revascularization referred for repeat angiography, to describe and the rate and mechanisms of MRF (stent or graft failure, coronary artery disease progression or residual coronary artery disease); to evaluate the management including medical treatment and SR of these patients; and to assess the prognosis according to the outlined causative mechanisms. The registry has one year follow up for the primary endpoint (Patient-oriented composite endpoint including all-cause death, any myocardial infarction or any new unplanned revascularization according to subsets of MRF), but extended follow-up will be carried out up to 5 years. CONCLUSION: The REVASEC Registry will provide updated data on the characteristics, patterns of treatment, and 1-year outcomes of patients with MRF and SR in contemporary clinical practice.

Adjunctive effect of modifying the implant-supported prosthesis in the treatment of peri-implant mucositis.

AIM: To evaluate the adjunctive effect of modifying the implant-supported prosthesis to facilitate access to oral hygiene when treating peri-implant mucositis. MATERIAL AND METHODS: A 6-month randomized clinical trial was designed. Patients with peri-implant mucositis were treated by implant surface debridement with plastic curettes and a plastic tipped ultrasonic device. Then, they were randomly assigned to either modifying their prosthesis to allow for better oral hygiene (test group) or not (control group). Subsequently in both groups, individualized oral hygiene instructions were provided. Clinical and radiographical outcomes were evaluated at baseline and 1, 3 and 6 months after treatment. RESULTS: 48 patients were included, and 45 completed the clinical trial (24 test and 21 control patients). After 6 months, changes in the modified bleeding index between the control and test groups were 0.50 (standard deviation -SD = 0.70) and 1.14 (SD = 0.96), respectively (p = 0.01). The changes in implant probing pocket depth at 6 months were -0.02 (SD = 0.61) and 0.31 (SD = 1.20) mm, respectively (p = 0.04). CONCLUSIONS: Modifying the contour of the prostheses to improve access for oral hygiene significantly improved the clinical outcomes after standard mechanical treatment of peri-implant mucositis.

The adjunctive effect of a titanium brush in implant surface decontamination at peri-implantitis surgical regenerative interventions: A randomized controlled clinical trial.

AIM: To evaluate an additional mechanical approach, a titanium brush, in the implant surface decontamination performed during the regenerative surgical therapy of peri-implantitis. MATERIAL AND METHODS: A randomized double-blinded clinical trial, with a 1-year follow-up, was carried out. After a hygienic phase, peri-implantitis-affected implants were randomly assigned to a control or to a test group. In the control group, implant surface was decontaminated both mechanically and chemically with 3% H2 O2 and plastic ultrasonic scalers, respectively, while in the test group, a titanium brush was also applied. Intrabony defects in both groups were filled with an alloplastic material (ß-tricalcium phosphate and hydroxyapatite) and covered with a collagen membrane. The primary outcome was the reduction in probing pocket depth (PPD) at the deepest site. RESULTS: Thirty patients were included, 15 in each group. At 12 months, reduction in PPD was 4.87 (standard deviation [SD] 1.55) mm and 2.85 (SD: 1.91) mm, respectively (p = 0.009). The correspondent figures for residual PPD were 3.6 (SD: 0.91) and 4.92 (SD: 1.26) mm, respectively (p = 0.007). CONCLUSIONS: The additional use of a titanium brush during regenerative treatment of peri-implantitis resulted in statistically significant benefits in terms of PPD reduction after 12 months.

Vancomycin and tobramycin impregnated mineralized allograft for the surgical regenerative treatment of peri-implantitis: a 1-year follow-up case series.

OBJECTIVES: To assess the clinical and radiographic outcomes of the regenerative treatment of peri-implantitis using a vancomycin and tobramycin impregnated allograft (VTA) after a 12-month period. MATERIAL AND METHODS: Thirteen consecutive patients who required a regenerative treatment of peri-implantitis were recruited. For the 17 implant sites, a flap was raised, and after mechanical and chemical implant decontamination, a vancomycin and tobramycin impregnated allograft was placed in the defect and then covered with a collagen membrane. Soft tissues were sutured allowing a non-submerged healing. Clinical and radiographic variables were evaluated at baseline and at 12 months after treatment. RESULTS: No signs of continuous bone loss were observed and no implant was lost, yielding a 100% survival rate. All patient's clinical examination at 12 months revealed peri-implant health showing absence of suppuration and a statistically significant reduction in terms of bleeding on probing scores (70.6%, P = 0.001). Initial probing pocket depth (7.88 ± 1.22 mm) was significantly reduced at 12 months healing, a mean reduction of 4.23 ± 1.47 mm (P = 0.001) was achieved. The mean radiological infrabony defect at baseline reached 4.33 ± 1.62 mm, and was significantly reduced up to 0.56 ± 0.88 mm, which represents an 86.99 ± 18.2% bone fill from the original infrabony defect. CONCLUSIONS: Within the limits of the study, the application of VTA with a collagen membrane yielded positive outcomes in terms of radiographic bone fill, pocket depth reduction, and attachment gain after a 12-month period. Thus, VTA plus a collagen membrane seem to be suitable for the regenerative treatment of peri-implantitis. CLINICAL RELEVANCE: The use of locally delivered antibiotic together with the bone graft may reduce the undesirable effects related to the systemic administration and the risk of resistances. In the light of the results obtained, these grafting materials might offer new treatment strategies in the surgical regenerative treatment of peri-implantitis.