Show simple item record

dc.contributor.authorKensara, Anmar
dc.date.accessioned2023-08-18T13:11:25Z
dc.date.available2023-08-18T13:11:25Z
dc.date.issued2023
dc.identifier.urihttp://hdl.handle.net/10713/20650
dc.descriptionUniversity of Maryland, Baltimore, School of Dentistry, Ph.D., 2023en_US
dc.description.abstractObjectives: To characterize the microbiome composition within and around dental implants of peri-implantitis subjects and within and around healthy implants using 16S rRNA gene sequencing, and to profile salivary inflammatory mediators associated with peri-implantitis compared to healthy controls from the same subjects. Methods: A total of 24 subjects (peri-implantitis n=14, healthy n=10) were enrolled in the study. From the 24 subjects, 24 endosseous implants from affected (peri-implantitis) and 14 healthy controls were included in this cross-sectional study. Samples for microbiological analysis were obtained from the internal surfaces of dental implants and peri-implant sulcus using sterile paper points. DNA was extracted and 16S rRNA gene was amplified using universal primers targeting the V3-V4 regions. Amplicons were sequenced using Illumina MiSeq platform. Alpha and beta diversity, core microbiome, and taxa differential abundance were assessed. Saliva was collected from the same subjects for immunology-based assays. Salivary inflammatory mediators in peri-implantitis and healthy implant subjects were profiled using antibody arrays. Results: A significant increase in microbial diversity was observed in the internal implant surface of healthy implants compared with the internal surfaces of peri-implantitis (Shannon P= 0.02), and no significant differences in microbial diversity between healthy implants sulci and peri-implantitis pockets (Shannon P= 0.82). Bacterial community structure was significantly different within implant in both healthy and peri-implantitis groups (P= 0.012) but not significantly different around implants in both healthy and peri-implantitis (P= 0.18). Enterococci is the predominant bacteria within peri-implantitis (LD >2.0, P< 0.05). Abundant species in peri-implantitis were C. leadbetteri, T. maltophilum, Peptostreptococcus, Neisseria, P. gingivalis, and P. endodontali, L. lactis and F. alocis (P < 0.05). Gram-positive bacteria such as S. salivaris, P. melaninogenica, L. wadei, and Actinomyces spp were more abundant in the peri-implant healthy sulcus. Around 48% of detected bacteria were cultivable in general media. In addition, out of 105 analytes examined in saliva, we found that 29 mediators were upregulated in subjects with peri-implantitis (P < 0.001). Conclusions: Our results indicate that microbial colonization of the internal implant surface may act as a major contributor to the etiology of peri-implant disease. Multiple inflammatory mediators were significantly elevated in the saliva of peri-implantitis patients compared to healthy implant patients.en_US
dc.language.isoen_USen_US
dc.subject.meshPeri-implantitisen_US
dc.subject.meshDental Implantationen_US
dc.subject.meshHLA-D Antigensen_US
dc.titleThe Etiology of Peri-implantitis: Microbiological Profile Within and Around Dental Implants and the Associated Human Immune Responseen_US
dc.typedissertationen_US
dc.date.updated2023-06-12T01:05:31Z
dc.language.rfc3066en
dc.contributor.advisorMasri, Radi, 1975-


Files in this item

Thumbnail
Name:
Kensara_umaryland_0373D_11445.pdf
Size:
4.073Mb
Format:
PDF

This item appears in the following Collection(s)

Show simple item record