Određivanje dozimetrijskih svojstava sintetičkih dentalnih koštanih nadomjestaka spektroskopijom elektronske paramagnetske rezonancije

master's thesis

• Title (english): Study of dosimetric properties of synthetic dental bone substitutes by electron paramagnetic resonance spectroscopy
• Author: Ivana Zgurić
• Mentor: Nadica Maltar Strmečki (mentor)
• Mentor: Miroslav Požek (komentor)
• Committee member: Miroslav Požek (predsjednik povjerenstva)
• Committee member: Nadica Maltar Strmečki (član povjerenstva)
• Committee member: Maja Planinić (član povjerenstva)
• Committee member: Mihael Makek (član povjerenstva)
• Committee member: Katarina Jeličić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Physics); Zagreb
• Defense date and country: 2020-10-23, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics

Abstract

U slučaju nekontroliranih radioloških ili nuklearnih nesreća potrebno je u što kraćem roku rekonstruirati nepoznate apsorbirane doze kod žrtava u svrhu određivanja odgovarajućih medicinskih protokola. Istraživanja su pokazala da je spektroskopija elektronske paramagnetske rezonancije (EPR) brza i osjetljiva metoda retrospektivne dozimetrije, te omogućuje brzu procjenu doze velikog broja pojedinaca u kratkom vremenskom periodu. Dozimetrija spektroskopijom elektronske paramagnetske rezonancije temelji se na detekciji nastalih radikala pri izlaganju ionizirajućem zračenju, mjerenja se vrše na radikalima nastalim u materijalima pronađenim blizu ili na samoj žrtvi zračenja. Kao prirodni dozimetar koristi se zubna caklina, no zbog čestih bolesti zuba ili nadogradnji izvađenih, sastav zuba se zamjenjuje s dentalnim koštanim nadomjestcima koji su uglavnom izrađeni od sintetičkih kompozita na bazi kalcijevog fosfata. Cilj ovog istraživanja bila je usporedba svojstava dozimetrijskih signala za tri komercijalno dostupna kompozitna materijala. Uz usporedbu više načina rekonstrukcije doze, te pomoću postojećih kalibracijskih modela određene su granice detekcije zubne cakline i tri različita kompozita. U sklopu diplomskog rada istražena je i stabilnost EPR signala navedenih uzoraka u vremenu.

Abstract (english)

In the case of uncontrolled radiological or nuclear accidents, it is necessary to reconstruct the unknown absorbed dose as soon as possible for determination of the appropriate medical protocols. Studies have shown that electron paramagnetic resonance (EPR) spectroscopy is a fast and sensitive method of retrospective dosimetry and allows for rapid dose assessment of many individuals in a short period of time. Dosimetry by electron paramagnetic resonance spectroscopy is based on the detection of formed radicals during exposure to ionizing radiation, measurements are performed on radicals formed in materials found near or on the radiation victim itself. Tooth enamel is used as a natural dosimeter, but due to frequent tooth diseases, restorations of lost ones or restoration with dental bone grafts that are mainly made of synthetic composites based on calcium phosphate. The aim of the study was to compare the properties of dosimetry signals for three commercially available composite materials. With the comparison of several methods of dose reconstruction, and with the help of existing calibration models, the limits of detection of tooth enamel and three different composites were determined. As part of the thesis, the stability of EPR signals over time of above samples were investigated.

• Keywords: zubna caklina; dozimetrija; EPR spektroskopija
• Keywords (english): tooth enamel; dosimetry; EPR spectroscopy
• Language: croatian
• URN:NBN: urn:nbn:hr:217:708541
• Study programme: Title: Physics; specializations in: Education; Course: Education; Study programme type: university; Study level: integrated undergraduate and graduate; Academic / professional title: magistar/magistra edukacije fizike (magistar/magistra edukacije fizike)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2021-01-04 13:24:49