College of Dentistry - M.Dent. Projects

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Browsing College of Dentistry - M.Dent. Projects by Subject "cytokines"

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    A 6-month comparison of piezo ultrasonic scaler and hand instrumentation in the maintenance of peri-implant tissues: a randomized clinical trial
    (2016) Castro, Maria; Atout, Reem; Renvert, A.; Cholakis, Anastasia
    Objectives: The aim of this study was to compare the clinical effects, presence of inflammatory cytokines, and the patients' perceived discomfort of two mechanical non-surgical methods of peri-implant maintenance: the piezo ultrasonic scaler vs hand instrumentation. Material and Methods: A total of thirty-four (34) patients with at least one healthy or with peri-implant mucositis dental implant were randomly assigned to the piezo ultrasonic scaler or to the hand instrumentation groups. The clinical parameters analyzed at the implant level were the following: Plaque Index (Pl), Bleeding on Probing (BOP), Probing Depths (PD), Keratinized tissue (KT) and Recession (REC). All these measurements were recorded at baseline, three, and six months. Full mouth plaque index (FPI) and full mouth bleeding on probing (FBOP) were also calculated. Samples of Peri-Implant Crevicular Fluid (PICF) from the four aspects of the implant were collected for analysis of cytokine levels followed by the corresponding maintenance therapy. At the end of the study patients were asked to fill in a pain questionnaire (Visual analogue scale, VAS). Results: Thirty-one (31) subjects completed the study (Piezo=17, SRP=14). Even though, reduction on FPI and FBOP were observed, it was found that the FPI and FBOP did not have a statistically significant difference over the 6 months or at any of the checkup times (0, 3, 6 months) for any of the treatment groups. Both peri-implant therapies slightly reduced the implant plaque index and implant probing depths in healthy and peri-implant mucositis implants from O to 6 months; however, these differences were not statistically significant. The model results indicated that the presence of KT and REC were not statistically significant different between treatments at any given time. This study demonstrated that the anti-inflammatory cytokine IL-4 statistically significant increased for both therapies from baseline to 6 months (P<0.05). There were not statistically association between the implant PD, Pl, and BOP and the cytokines levels (IL-2, IL-4, IL-6, ILB, IL-10, TNFa, and IFNy) during the six-month study period. In addition, subjects from both therapies reported minimum perceived discomfort after treatment. Conclusion: Within the limits of this study, it was demonstrated that both peri-implant therapies had a beneficial clinical effect in the reduction of all clinical parameters; however, these results were not statistically significant. In addition, there was no statistically significant difference in the clinical outcomes measurements at any given time between the two groups and the study could not demonstrated that peri-implant therapy decreases the presence of inflammatory cytokines.
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    A comparison of the efficacy of two different interdental protocols around dental implants in maintenance patients: a randomized controlled trial
    (2015) Nwachukwu, Omonkhele G.; Renvert, S.; Cholakis, Anastasia; Atout, Reem
    Background: Although there are multiple studies comparing the efficacy of different interdental hygiene aids on natural teeth, little or no data exists to show what method of interdental cleaning may be most effective on dental implants. The aim of this study was to compare the effectiveness of two interdental hygiene aids (an interdental brush v. dental floss) on dental implants, assessing their effects on clinical parameters that impact on impact tissue health, as well as cytokines in peri-implant crevicular fluid. Method: This was a single blind, randomized controlled trial in a single centre. Thirty-two implant patients currently under maintenance was evaluated at baseline, 3 and 6 months. One implant was studied per participant. Sixteen patients used dental floss while the other 16 used interdental brushes. All hygiene aids used were supplied to participants after randomized allocation. Clinical parameters evaluated include full-mouth plaque scores and full-mouth bleeding on probing, width of implant keratinized mucosa, distance of papilla from the occlusal point of prosthesis, implant probing depths, implant plaque levels and implant bleeding on probing. Peri-implant crevicular fluid samples were also taken and IL-2, IL-4, IL-6, IL-10, TNF-alpha and IFN-gamma levels were measured. Results: The mean and median levels of all clinical variables and cytokines for both groups were calculated and compared analytically. A repeated measures analysis to compare group-time interaction was also carried out. There were reductions from baseline to 6 months in most variables for both groups. While most results were not statistically significant, there was an increase in mean probing depth of interdental brush group at 6 months for the distobuccal (0.4mm) and lingual (0.25mm) implant surfaces that was statistically significant. Conclusion: Although floss slightly outperformed interdental brushes in implant plaque index and full mouth bleeding scores, other indices showed relatively comparative values between the two groups. We were unable to reject the null hypothesis as determined within the limits of these 6-months results.
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    A Randomized Clinical Trial of the in vivo effect of non-metallic vs metallic hand scalers on zirconia implant supported crowns during a year of peri-implant maintenance
    (2019) Roemermann, Dayna L.; Atout, Reem; Franca, R.; Pesun, I.; Cholakis, Anastasia
    Background: This study examined whether the degree of abutment surface modification that may occur with regular periodontal instrumentation has a clinical impact in terms of increased plaque accumulation and increased peri-implant tissue inflammation on zirconia implant abutments. Methods: 13 patients who had zirconia implant crowns were recruited in this randomized clinical trial. Each patient acted as their own control, and had either the buccal or lingual surface of their screw retained implant restoration scaled with a metallic scaler, and the other surface with a non-metallic scaler at 3, 6, 9 and 12 months. Cytokine testing of the peri-implant crevicular fluid was completed at 0, 3 and 12 months, for IL-2, IL-4, IL-6, IL-8, IL-10, TNF-a or IFNy. Implant crowns were removed at 12 months and evaluated under an atomic force microscope for the RA, or average roughness, and the Ra, or root mean square roughness, scores. The implant crowns were polished and re-inserted. Results: There were strong significant differences in surface roughness (Ru and Ra) between the metallic and non-metallic scalers, with average Ru values of 417.7m (s = 276.1nm) and 233.9nm (s = 155.6nm), and RA values of 301.0nm (s = 214.2nm) and 176.1nm (s = 123.1nm) respectively. However, there were no significant associations between the type of scaler used and the amount of clinical inflammation or cytokine production. Conclusion: Metallic scalers produce deeper, more aggressive surface alterations to the abutment/crown zirconia surface but there was no statistically significant difference between the degree of surface alterations, amount of BOP, and the amplitude of cytokine inflammation produced.
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    Role of oral microbiota and intrinsic host factors in peri-implantitis – a pilot study
    (2022-04-26) Enghiad, Setareh; Stavropoulou, Chrysi (Dr. Gerald Niznick College of Dentistry); Cholakis, Anastasia (Dr. Gerald Niznick College of Dentistry); Chelikani, Prashen (Dr. Gerald Niznick College of Dentistry); Bhullar, Raj
    Introduction: Although many studies have evaluated microbial composition of peri-implant pockets, the role of mycobiome on peri-implantitis is not well established. Objectives: The aim of this study is to characterize the role of oral microbiota in peri-implant health and disease by determining the composition of the oral bacteriome and mycobiome from subgingival dental plaque, cytokine profile in the crevicular fluid, and to determine if there are any relationships between the oral microbiota, cytokine profile and peri-implant health and disease. Methods: Gingival crevicular fluid and subgingival plaque samples were collected from 20 periodontally healthy patients with healthy implants [Group H] and 9 periodontally healthy patients with peri-implantitis [Group P]. Eight IL-1β, IFN-γ, IL-2, IL-4, IL-6, IL-8, IL-10, and TNF-α were analyzed in crevicular fluid samples isolated from both groups. 16S rRNA and ITS rRNA amplicon sequencing was performed to detect bacterial and fungal species. Results: No statistically significant difference was found in concentrations of IL-2, IL-8, IL-10, and TNF-α. However, statistically significant differences were observed for IL-4 and IL-6. Alpha diversity analysis showed a significant difference between the groups H - Implant vs. P - Tooth and P - Implant vs. P - Tooth. Significant differences in species abundances were also observed between Group H and Group P. Candida parapsilosis and Aspergillus restrictus were significantly enriched in the Group P. Conclusions: To the best of our knowledge, this is the first time Aspergillus restrictus is related to peri-implantitis. Moreover, we found that the relative abundance of Candida parapsilosis is significantly higher in peri-implantitis sites. Our findings further challenge the concept that peri- implantitis is a bacterial disease with specific bacterial pathogens and strengthens the idea that bacterial invasion happens secondary to bone loss because of not very well understood processes such as foreign body reaction.