Evaluation of the antimicrobial efficacy of different types of photodynamic therapy on the main pathogenic bacteria of peri-implantitis in vitro

doctoral thesis

• Title (croatian): Procjena antimikrobne učinkovitosti različitih vrsta fotodinamske terapije na uzročnike periimplantitisa in vitro
• Author: Bleron Azizi
• Mentor: Dragana Gabrić (mentor)
• Mentor: Ana Budimir (komentor)
• Committee member: Irina Filipović Zore (predsjednik povjerenstva)
• Committee member: Jasmina Vraneš (član povjerenstva)
• Committee member: Darije Plančak (član povjerenstva)
• Committee member: Darko Božić (član povjerenstva)
• Committee member: Mato Sušić (član povjerenstva)
• Granter: University of Zagreb; School of Dental Medicine; (Department of Oral Surgery); Zagreb
• Defense date and country: 2018-03-06, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Dental Medicine; Oral Surgery
• Universal decimal classification (UDC): 616.31 - Stomatology

Abstract

The aim of this study was to evaluate the efficacy of antimicrobial photodynamic therapy (aPDT) against a bacterial suspension prepared from three different bacterial species on titanium and zirconia dental implants, and to analyze the possible alterations of the implant surfaces as a result of aPDT. The study was conducted on 72 titanium dental implants and 72 zirconia dental implants contaminated with a bacterial suspension prepared from three bacterial species. The contaminated implants were randomly divided into four experimental groups and two control groups (n=12 each), according to the following treatment protocols: Group 1 (PDT1): PDT (660 nm, 100 mW, 60 seconds) with toluidine blue; Group 2 (PDT2): PDT (660 nm, 100 mW, 60 seconds) with phenothiazine chloride dye; Group 3 (PDT3): light emitting diode (LED) with toluidine blue; Group 4 (TB): treatment with only toluidine blue for 60 seconds. In the positive control (PC) group, the implants were treated with a 0.2% chlorhexidine-based solution for 60 seconds, and in the negative control (NC) group no treatment was used. In the titanium implants, the highest bacterial reduction was recorded in the PDT1 (98.3%) and PDT2 (97.8%) groups. Results of this study showed that there was a statistically significant reduction of bacteria in the PDT1 and PDT2 groups compared to the NC group (<0.05), individually for each bacterial species, as well as for all three species together. PDT3 was less effective than PDT1 and PDT2, and did not show a statistically significant difference compared with NC or any other treatment group. TB was the least effective treatment in terms of both the total bacterial count and the individual count for each bacterial species. In the zirconia implants all the study groups had significantly lower bacterial counts (>99.9%) when compared with NC for the total bacterial count and each bacterial species separately. Among them the highest bacterial reduction was recorded in PDT1, PDT2 and PDT3, and all of them were also significantly different from TB. PDT1 and PDT2 protocols showed high efficacy against a three-day old bacterial biofilm on titanium dental implants, while PDT1, PDT2 and PDT3 showed high efficacy on zirconia implants.

Abstract (croatian)

Cilj ove studije bio je procijeniti učinkovitost antimikrobne fotodinamske terapije (aPDT) u trodnevnoj bakterijskoj suspenziji pripremljenoj od tri različite bakterijske vrste primijenjene na površinu titanskih i cirkonskih dentalnih implantata, te analizirati moguće promjene površina implantata kao rezultat djelovanja aPDT-a.
Istraživanje je provedeno na 72 titanska dentalna implantata i 72 cirkonska dentalna implantata kontaminirana bakterijskom suspenzijom pripremljenom od tri bakterijske vrste: Prevotella intermedia, Aggregatibacter actinomycetemcomitans i Porphyromonas gingivalis. Kontaminirani implantati su inkubirani u anaerobnim uvjetima kroz 72 sata, a potom slučajnim odabirom podijeljeni u četiri eksperimentalne skupine i dvije kontrolne skupine (n = 12 po skupini) prema sljedećim protokolima tretiranja: Grupa 1 (PDT1): PDT (660 nm, 100 mW, 60 sekundi) s toluidinskim modrilom; Grupa 2 (PDT2): PDT (660 nm, 100 mW, 60 sekundi) s fenotiazinskim kloridnim bojilom; Grupa 3 (PDT3): svjetleća dioda (LED) s toluidinskim modrilom; Skupina 4 (TB): tretiranje samo toluidinskim modrilom kroz 60 sekundi. U pozitivnoj kontrolnoj skupini (PC) implantati su tretirani s 0,2%-tnom klorheksidin-baziranom otopinom tijekom 60 sekundi, a u negativnoj kontrolnoj skupini (NC) nikakav tretman nije korišten.
U skupini titanskih implantata, najviše redukcije bakterija zabilježeno je u skupinama PDT1 (98,3%) i PDT2 (97,8%). Rezultati ovog istraživanja pokazali su statistički značajno smanjenje bakterija u skupini PDT1 i PDT2 u usporedbi s NC grupom (<0,05), pojedinačno za svaku vrstu bakterija, kao i za sve tri vrste zajedno. PDT3 je bio manje učinkovit nego PDT1 i PDT2 i nije pokazao statistički značajnu razliku u usporedbi s NC ili bilo kojom drugom skupinom tretiranja. TB je bio najmanje učinkovit tretman, s obzirom na ukupni broj bakterija i pojedinačni broj za svaku pojedinu vrstu bakterija.
U skupini cirkonskih implantata sve ispitivane skupine imale su znatno niži broj bakterija (> 99,9%) u usporedbi s NC za ukupni broj bakterija i svaku bakterijsku vrstu odvojeno. Među njima je najveće smanjenje bakterija zabilježeno u slučaju korištenja PDT1, PDT2 i PDT3, od kojih su svi bili statistički značajno različiti od TB. PDT1 i PDT2 protokoli pokazali su visoku djelotvornost protiv trodnevnog bakterijskog biofilma na titanskim dentalnim implantatima, dok su PDT1, PDT2 i PDT3 pokazali veliku učinkovitost na površini cirkonskih implantata.

• Keywords: photodynamic therapy; titanium implants; zirconia implants; antimicrobial efficacy; implant surface; laser; LED
• Keywords (croatian): fotodinamska terapija; titanski implantati; cirkonski implantati; antimikrobni učinak; površina implantata; laser; LED
• Language: english
• URN:NBN: urn:nbn:hr:127:870752
• Study programme: Title: dental medicine; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti, područje biomedicine i zdravstvo, polje dentalna medicina (doktor/doktorica znanosti, područje biomedicine i zdravstvo, polje dentalna medicina)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2018-11-26 10:51:25