Accuracy of ceramic crowns made by optical scanning methods of Cerec®3D system

Abstract

Introduction: The results of many years technological development of Cerec® 3D CAD/CAM system, is implementation one intraoral and two extraoral optical scanning methods. Aim: The aim of this study was to determine the precision of ceramic crowns made by optical scanning methods of Cerec®3D system. Methods: The study was conducted in three experimental groups of ceramic crowns in whose manufacturing was applied three optical scanning methods of Cerec®3D system. Control group consisted of metalceramic crowns made by conventional methodology. The accuracy of ceramic crowns was examined by measuring of the marginal gap size between edge of crowns and demarcation by scanning electron microscope (SEM). Results: The research found, that there is a difference in the accuracy of ceramic crowns made by Cerec®3D system. The highest level of accuracy was recorded in the group of crowns made by technique extraoral optical superficial scanning (31,64±9,45μ). Marginal gap size crowns made with technique intraoral optical superficial scanning showed a lower level of accuracy (50,27±31,50μ). Value of marginal gap size crowns made by technique extraoral laser point scanning was 102,58+31,23μ. Conclusion: Ceramic crowns made by Cerec®3D optical scanners show a high and clinically acceptable precision level.

Uvod: Dugogodišnji razvoj Cerec®3D CAD/CAM sistema implementirao je u praktičnu upotrebu jednu intraoralnu i dve ekstraoralne metode optičkog skeniranja. Cilj: Cilj rada je bio da se utvrdi stepen preciznosti keramičkih kruna izrađenih primenom različitih tehnika optičkog skeniranja Cerec®3D sistema. Materijal i metod: Ispitivanje je sprovedeno u okviru tri eksperimentalne grupe kruna u čijoj izradi su primenjeni različiti postupci skeniranja Cerec®3D sistema. Metalokeramičke krune izrađene konvencionalnom metodologijom predstavljale su kontrolnu grupu. Preciznost kruna ispitivana je merenjem veličine marginalnog zjapa između ruba krune i demarkacije preparacije pomoću skenirajućeg elektronskog mikroskopa (SEM). Rezultati: Rezultati istraživanja pokazuju da postoji razlika u preciznosti kruna izrađenih primenom različitih metoda skeniranja Cerec®3D sistema. Najviši stepen preciznosti (31,64±9,45μ) zabeležen je kod kruna u čijoj izradi je primenjena tehnika optičkog ekstraoralnog površinskog skeniranja, nešto niži stepen preciznosti (50,27±31,50μ) imale su krune izrađene tehnikom intraoralnog optičkog površinskog skeniranja. Krune izrađene primenom tehnike ekstraoralnog tačkastog skeniranja imale su stepen preciznosti od 102,58±31,23μ. Zaključak: Krune izrađene primenom optičkih metoda skeniranja Cerec 3D sistema pokazuju visok i klinički prihvatljiv stepen preciznosti.