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Objective: The purpose of this study was to evaluate the sterilization effectiveness against biofilms on retrieved healing abutments used in implant dentistry. Background: A large number of clinicians reuse healing abutments to decrease treatment costs although it can promote infection due to the presence of remnant biofilm biomass. Methods: One hundred and eighty‐five titanium healing abutments previously used for 3 months in oral cavity were assessed in this study. Abutments were submitted to cleaning, chemical disinfection, and autoclave sterilization according to clinical guidelines. The abutments were aseptically placed into glass tubes containing specific bacterial growth medium and then incubated for 10 days. From glass tubes with bacterial growth, 100 µl medium was transferred to Schaedler's agar for morphological identification and counting of strict anaerobes and to Columbia blood agar for presumptive identification of facultative anaerobes after incubation. Isolated strains were then identified at species level by enzymatic and biochemical tests within API microorganism detection platform. Also, polymerase chain reaction (PCR) was performed for identification of undefined strains. Results: After the standard cleaning and sterilization procedures, fifty‐six (approximately 30%) retrieved abutments showed the presence of remnant biofilm biomass. The bacteria identified into the remnant biofilms covering the abutments were representative of the commensal oral microbiota including Aggregatibacter actinomycetemcomitans, Prevotella intermedia, and Enterococcus faecalis. Conclusion: Although some healing abutments did not reveal the existence of bacteria, organic components from biofilm biomass are still strongly adhered on the retentive micro‐regions and surfaces of abutments and therefore that would support the accumulation of biofilm including pathogenic species leading to patients' cross‐infections. Further studies should be performed on the assessment of different materials, design, and connections of the healing abutments associated with clinical disinfection procedures in implant dentistry. [ABSTRACT FROM AUTHOR]

Purpose: To compare the subgingival microbiota around two differently designed implant systems that were in function for more than 12 years in a randomised split-mouth study design, and to compare the outcome with natural dentition. Materials and methods: A total of 18 partially edentulous patients received at least two TiOblast™ (Astra Tech) and two Branemark (Nobel Biocare) implants following a split mouth design. At the last follow-up visit, periodontal parameters (probing depth, bleeding on probing and plaque) were recorded and intraoral radiographs were taken to calculate bone loss. Subgingival plaque samples were collected for culture, qPCR and checkerboard DNA-DNA hybridisation analysis. These data were related to implant design and bone loss. This study setup allowed a comparison of 34 Astra Tech (Impl A) with 32 Branemark (Impl B) implants. Results: During the 12-year follow up, five patients dropped out. One Branemark implant was lost before abutment connection in a dropout patient. Mean bone loss between loading and year 12 was 0.7 mm (range: -0.8–5.8) (Impl A), and 0.4 mm (range: 1.1–4.1) (Impl B). No significant microbiological differences (qualitative and quantitative) could be observed between both implant types. Compared to teeth, subgingival plaque samples from implants did not reach the concentration of pathogens, even after 12 years of function. Conclusions: These data show that both implant systems (with differences in macro-design and surface characteristics), in patients with good oral hygiene and a stable periodontal condition, can maintain a successful treatment outcome without significant subgingival microbiological differences after 12 years of loading. The presence of periodontopathogens did not necessarily result in bone loss. [ABSTRACT FROM AUTHOR]

Recent research indicated that periopathogens colonize, besides the pockets, also other niches within the oral cavity including: the soft tissues, the saliva, the tongue, and even the tonsils. Since the supragingival plaque and the bacteria in these niches have a major impact on the subgingival plaque colonisation but especially on the recolonation after debridement, it seems reasonable to expect that a one-stage, full-mouth disinfection protocol, involving the bacteria over the entire oro-pharyngeal area, has a significantly better outcome when compared to a more staged approach (e.g. with treatments per quadrant). Since several review papers recently discussed the benefits of a one-stage, full-mouth disinfection protocol, pointing to some shortcomings in the our research protocol or with an attempt to compare the data of the new approach with other studies (with unfortunately non comparable approaches), this review paper aims to clarify some of the confusion concerning the benefits of a one-stage, full-mouth disinfection approach. [ABSTRACT FROM AUTHOR]

Objectives: Examine the clinical and microbiological benefits of a dual‐strain Lactobacillus reuteri probiotic on the non‐surgical therapy of initial peri‐implantitis. Materials and methods: This randomized, double‐blind study targeted patients with initial peri‐implantitis, that is peri‐implantitis with a maximum mean probing pocket depth of 6 mm and maximum 3 mm bone loss compared with loading. A full‐mouth prophylaxis was performed and the peri‐implantitis sites were debrided. Subsequently, local application of the study drops was carried out at the peri‐implantitis sites and the study lozenges were handed out. The patients in the probiotic group received drops and lozenges containing L. reuteri (ATCC PTA 5289 & DSM 17938), those in the control group received placebo products. At the implant level the measurements of interest were bleeding, probing pocket depth and plaque. Full‐mouth bleeding and plaque scores were also recorded. Microbiological samples were taken from the tongue, saliva and subgingivally around the implants. Results: All clinical parameters were significantly decreased after 12 and 24 weeks. At the implant level the only statistically significant difference was a greater decrease in plaque levels in the probiotic versus the control group (p =.002 at 24 weeks). At the full‐mouth level, the only intergroup difference was the greater decrease in full‐mouth bleeding on probing sites in the probiotic group compared with the control group (p <.001 at 24 weeks). Concerning the microbiological outcomes, no significant differences could be found at any time point, neither intra‐ nor intergroup. Conclusions: No adjunctive effects of the use of L. reuteri probiotics in the treatment of peri‐implantitis were found. [ABSTRACT FROM AUTHOR]

Aim: The aim of the study was to evaluate whether the use of a xenograft is not inferior to the use of xenograft and autogenous bone chips in treating dehiscences at implant placement. Materials and Methods: After implant placement, leaving a dehiscence, control sites were treated using a composite graft (autogenous bone chips and xenograft) and at the test sites 100% xenograft was used. Both sites were covered with a resorbable collagen membrane. Dehiscences were measured clinically at implant placement and at re‐entry. CBCT was taken immediately after implant placement and after 4 months. Results: In total, 28 GBR procedures were performed in 14 patients. On average, the change in vertical defect height was 2.07 mm (46.7%—test group) and 2.28 mm (50.9%—control group) (p >.05). The horizontal defect width at the implant shoulder change on average 1.85 mm (40.5%—test group) and 1.75 mm (40.9%—control group) (p >.05). On average, a loss in augmentation thickness of 0.45 mm (68.9%—test group) and 0.64 mm (55.5% control group) between implant placement and augmentation and abutment surgery was obtained at the implant shoulder. Conclusion: Both treatment modalities seem to work to a certain extent. At implant shoulder level, the augmentation thickness seems to be disappeared after the healing phase. (NCT03946020). [ABSTRACT FROM AUTHOR]

Aim: To examine the adjunctive effect of a Lactobacillus reuteri probiotic (ATCC PTA 5289 & DSM 17938) on the re‐instrumentation of residual pockets. Materials and Methods: This randomized, double‐blind, placebo‐controlled study included 39 previously non‐surgically treated periodontitis patients. A re‐instrumentation was carried out, and probiotic and/or placebo drops were applied according to the study protocoll. Patients afterwards received lozenges to use 2×/day for 12 weeks. Probing pocket depth (PPD), recession, bleeding on probing and plaque levels were analysed, next to the microbiological impact. Results: No effects of the probiotic drops could be found. However, after 24 weeks, the overall PPD in the probiotic lozenges group (2.64 ± 0.33 mm) was significantly lower compared to the control lozenges (2.92 ± 0.42 mm). This difference was even more pronounced in moderate (4–6 mm) and deep (≥7 mm) pockets. In the probiotic lozenges group, there were also significantly more pockets converting from ≥4 mm at baseline to ≤3 mm at 24 weeks (67 ± 18% versus 54 ± 17%) and less sites in need for surgery (4 ± 4% versus 8 ± 6%). However, the probiotic products did not influence the microbiological counts of the periodontopathogens. Conclusion: The adjunctive consumption of L. reuteri lozenges after re‐instrumentation improved the PPD reduction, without an impact on pocket colonization with periodontopathogens. [ABSTRACT FROM AUTHOR]

There is some evidence that periodontitis increases the risk of atherothrombosis. Abdominal aortic aneurysm (AAA) is a cardiovascular disease with specific risk factors and physiopathological mechanisms that can lead to rupture in the absence of treatment. The aim of the present systematic review was to explore the influence of periodontitis on the progression of AAAs as a specific disease. A systematic search in PubMed/MEDLINE and Embase databases was performed. Human and animal studies exploring the influence of periodontal pathogens on the progression of AAA were considered for inclusion. After systematic screening, 5 articles were included in the review. Due to the heterogeneity of the selected studies, a meta-analysis could not be performed. The descriptive analyses of the studies emphasized that periodontal pathogens or their by-products contribute to systemic and local innate immunity likely to be associated with AAA physiopathology. Periodontitis seems to play a role in the development and progression of AAA. The present systematic review suggests that the presence of periodontal bacteria in the bloodstream or in situ in the vascular lesion is a risk associated with aneurysmal disease progression. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to evaluate surface changes on dental implant systems and ions release after immersion in fluoride and hydrogen peroxide. Methods: Ten implant‐abutment assemblies were embedded in acrylic resin and cross‐sectioned along the implant vertical axis. Samples were wet ground and polished. Delimited areas of groups of samples were immersed in 1.23% sodium fluoride gel (F) or in 35% hydrogen peroxide (HP) for 16 min. Gels (n = 3) were collected from the implant surfaces and analyzed by inductively coupled plasma mass spectrometry (ICP‐MS), to detect the concentration of metallic ions released from the implant systems. Selected areas of the abutment and implant (n = 15) were analyzed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). Results: SEM images revealed surface topographic changes on implant‐abutment joints after immersion in fluoride. Implants showed excessive oxidation within loss of material, while abutment surfaces revealed intergranular corrosion after immersion in fluoride. ICP‐MS results revealed a high concentration of Ti, Al, V ions in fluoride after contact with the implant systems. Localized corrosion of implant systems could not be detected by SEM after immersion in hydrogen peroxide although the profilometry showed increase in roughness. ICP‐MS showed the release of metallic ions in hydrogen peroxide medium after contact with dental implants. Conclusion: Therapeutical substances such as fluorides and hydrogen peroxide can promote the degradation of titanium‐based dental implant and abutments leading to the release of toxic ions. [ABSTRACT FROM AUTHOR]

• Nanoemulsion appears to be an excellent nanocarrier for photodynamic application. • Chlorin-e6 incorporated in nanoemulsion showed great physicochemical and biophotonic parameters. • The combination of chlorin-e6 and LL-37 peptide in nanoemulsion is effective to eliminate periodontal pathogenic bacteria. In our previous studies, Chlorin-e6 (Ce6) demonstrated a significant reduction of microorganisms' viability against multi-species biofilm related to periodontitis while irradiated with blue light. However, the conjugation of Ce6 and antimicrobial peptides, and the incorporation of this photosensitizer in a nanocarrier, is still poorly explored. We hypothesized that chlorin-e6 conjugated to the antimicrobial peptide LL-37 loaded nanoemulsion could inhibit a multi-species biofilm related to periodontitis during photodynamic therapy (PDT), the pre-treatment with hydrogen peroxide was also tested. The nanoemulsion (NE) incorporated with Ce6 was characterized regarding the physiochemical parameters. Images were obtained by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Later, the Ce6 and LL-37 incorporated in NE was submitted to UV–Vis analysis and Reactive Oxygen Species (ROS) assay. Finally, the combined formulation (Ce6+LL-37 in nanoemulsion) was tested against multi-species biofilm related to periodontitis. The formed nanoformulation was kinetically stable, optically transparent with a relatively small droplet diameter (134.2 unloaded and 146.9 loaded), and weak light scattering. The NE system did not impact the standard UV–VIS spectra of Ce6, and the ROS production was improved while Ce6 was incorporated in the NE. The combination of Ce6 and LL-37 in NE was effective to reduce the viability of all bacteria tested. The treatment with hydrogen peroxide previous to PDT significantly impacted bacterial viability. The current aPDT regimen was the best already tested against periodontal biofilm by our research team. Our results suggest that this combined protocol must be exploited for clinical applications in localized infections such as periodontal disease. - Nanoemulsion demonstrated to be an excellent nanocarrier for photodynamic application. - Chlorin-e6 incorporated in nanoemulsion showed great physicochemical and biophotonic parameters. - The combination of chlorin-e6 and LL-37 peptide in nanoemulsion is effective to eliminate periodontal pathogenic bacteria. - The treatment with hydrogen peroxide previous to PDT significantly impacted bacterial viability. [ABSTRACT FROM AUTHOR]