Method for Regulation of Polymethyl Methacrylate Eye Prosthesis Wettability by Using Ultraviolet Radiation
2017
Linda Lancere

Defending
26.06.2017. 14:00, Mašīnzinību, transporta un aeronautikas fakultāte, Viskaļu 36a, 405.auditorijā

Supervisor
Jurijs Dehtjars

Reviewers
Viktors Mironovs, Jānis Maniks, Sigitas Tamulevicius

Polymethylmethacrylate eye prosthesis surface starts worsening in one year, deterioration in wettability of the prosthesis surface decreases user comfort and causes eyelid inflammation, eye prosthesis must be replaced with a new one – wettability is not restored in usual prosthetists practice. Though, if timely restored, mentioned complications could be avoided, the life of an eye prosthesis could be prolonged and costs for the patient reduced. Existing surface wettability regulation methods engage technologies like material processing in vacuum, usage of plasma, chemical and biological methods, which are complicated and expensive, they can only be realized in laboratory environment or are not persistent using eye drops, for example. At the moment there is no PMMA prosthesis surface processing regulation method that is simpler and more economic than previous existing methods. Such a method can be reached using UV radiation in room conditions, that alters the density of electric potential (being component of surface energy) of prosthesis and and influences wettability. The aim of the doctoral thesis is to develop a method for eye prosthesis surface wettability regulation of PMMA surface by using UV radiation in room conditions. The PhD thesis consists of preamble, review of literature sources concerning PMMA material applications in eye prosthetics and problems related to surface wettability, it’s interaction with UV light, existing surface modification technologies. Experimental part describes development of the research method to reach PMMA surface regulation method, influence of surrounding environment on sample wettability regulation. This part also describes UV influence on PMMA surface electric potential, wettability, chemical structure and morphology. As a result of this research, a method of PMMA wettability regulation has been developed that uses UV radiation in 200-400 nm wavelength range to induce surface electric potential. It was determined, that both hydrophilic and hydrophobic PMMA surface properties can be obtained in dependence of used exposure time. The most suitable modes have been identified to ensure wettability alterations. Non-ionizing radiation causes both surface electrical potential alterations and chemical processes in the same time – making no influence on surface roughness, which is essential in short and long term applications. Aprobation of obtained results has been also described, determining influence of alterations reached by UV radiation on microorganism adhesion and influence on nano coating surface electric potential induction, conclusions have been made and list of literature composed.


Keywords
Polimetilmetakrilāts, UV, slapināšana, acu protēzes, virsmas elektriskais potenciāls

Lancere, Linda. Method for Regulation of Polymethyl Methacrylate Eye Prosthesis Wettability by Using Ultraviolet Radiation. PhD Thesis. Rīga: [RTU], 2017. 101 p.

Publication language
Latvian (lv)
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