Utjecaj položaja bravice ortodontskog aparata na naprezanje u jednokorijenskom zubu

master's thesis

• Title (english): Stress influence of fixed orthodontic device bracket on single root tooth
• Author: Marko Blašković
• Mentor: Tanja Jurčević Lulić (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2016-07-15, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering

Abstract

Svrha ovog rada je analiza utjecaja položaja bravice fiksnog ortodonskog aparata naprave na jednokorjenski zub, njegov parodontni ligament (PDL) i odgovarajući dio kosti čeljusti. Fiksni ortodonski aparat se sastoji od metalnih bravica koje se lijepe na zub i međusobno su povezane žicom koja ima opružni efekt, a koristi se kod ljudi kojima je propisana dentalna terapija. Princip rada naprave je da bravice koje su pričvršćene na zub guraju zub u željeni položaj pomoću žice. Napravljeni su 3D modeli zuba, PDL-a i kosti. Modeli su napravljeni pomoću 377 CBCT (Cone beam računalna tomografija) snimaka anonimnog pacijenta kojemu je preporučena ortodonska terapija. Računalna tomografija (CT) je metoda stvaranja trodimenzionalne slike unutrašnjosti ljudskog tijela, na osnovu velike serije dvodimenzionalnih RTG snimaka koji su dobiveni oko zajedničke osi rotacije. Za razliku od klasičnog CT-a, CBCT ima snop zrake u obliku stošca te je puno manji i jeftiniji, stoga mu je omogućena primjena u svakoj stomatološkoj ordinaciji. Snimke su ubačene u programski paket „Mimics 17“ gdje je izdvojen model željenog jednokorjenskog zuba, PDL-a i kosti. Zbog različitih materijalnih svojstva zub je podjeljen na vanjski dio - caklinu i unutarnji dio - dentin. Caklina je čvrsto mineralno tkivo koje prekriva dentin. Zbog velikog udjela mineralnih tvari caklina je najtvrđa tvar u ljudskom tijelu. Caklina ima visok modul elastičnosti, tvrda je i krhka zbog čega uvijek mora biti poduprta dentinom, jer se u protivnom lako lomi. Geometriju svih 3D modela je bilo potrebno izgladiti i popuniti kako bi se mogla napraviti mreža konačnih elemenata. Analiza naprezanja, pomaka i deformacija konačnim elementima je napravljena u programskom paketu „Abaqus“. Definirana su sedam slučajeva opterećenja ovisno gdje se nalazi bravica proteze i je li djeluje žvačna sila na zub. Rezultati analize prikazani su u zadnjem poglavlju rada.

Abstract (english)

Purpose of this thesis is influence analysis of fixed dental braces position on single-rooted tooth, his periodontal ligament (PDL) and corresponding part of bone from jaws. Fixed dental braces are made of braces that are glued to the teeth and linked with wire that have spring effect. It is used on a people which have prescribed dental treatment. Work principle of this device is that braces on teeth push teeth in wanted position with a spring effect from a wire. 3D models of tooth, PDL and bone are made with 377 CBCT (Cone beam computed tomography) recordings of anonymous patient which have prescribed dental treatment. Computed tomography (CT) is method for creating tridimensional picture of interior of human body, based on large series of two dimensional RTG recordings which are made around common rotational axis. Unlike classic CT, CBCT X-rays are divergent, forming a cone. Device is smaller and cheaper so it has application in every dental clinic. Recordings are transferred in „Mimics 17“ software package where 3D models of wanted single-rooted tooth, PDL and bone are separated. Tooth is separated to two parts, outer- enamel and inner- dentin, because of different material properties. Enamel is hard mineral tissue which covers dentin. Because of large share of mineral substances enamel is hardest substance in human body. Enamel have high value of Young's modulus, it's hard and fragile so it need to be supported with dentin. Geometry of all 3D models needs to be filled and patched up in order to create finite element mesh. Stress, shift and deformation analysis with finite elements is made in „Abaqus“ software package. Seven cases of load are defined depending from postion of dental braces and application of bite force. Results of analysis are shown in last chapter of thesis.

• Keywords: biomehanika zuba; ortodonska terapija; žvačna sila; ortodonska sila; metoda konačnih elemenata
• Keywords (english): tooth biomechanics; dental therapy; bite force; orthodontic force; finite element method
• Language: croatian
• URN:NBN: urn:nbn:hr:235:990213
• Study programme: Title: Mechanical Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka strojarstva (magistar/magistra inženjer/inženjerka strojarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2019-05-22 16:56:49