فشل القشور الخزفية المصنوعه من السيراميك باستخدام تقنيات اللصق المختلفة : دراسة مقارنة مختبرية == Failures of Porcelain Laminate Veneers Using Different Techniques of Bonding (A Comparative In Vitro Study)
Author name:
صفا عدنان كعيد
Supervisor name:
عمار عطا الله علي السعدي
General topic:
Dentistry
Specific topic:
Oral and Maxillofacial Surgery
Degree:
Master
University:
Mustansiriyah University
Language:
English
University location:
Baghdad
First pages:
20T395 - p.pdf
Abstract:
Esthetic dentistry as a concept and adhesive materials development as a functional element make the new dawn of dentistry especially with the continuous development of adhesive techniques. This study is to evaluate the failure patterns of porcelain laminate veneers used to esthetically restore maxillary first premolar by bonding them to enamel and dentin with two different techniques.Forty eight extracted human maxillary first premolar were used for this study. Teeth were divided randomly into one control group and three experimental groups of twelve teeth eachGroup (A) were prepared in enamel (0.5 mm) depth of preparation. Group (B) were prepared in dentin (1 mm) depth of preparation and their veneers were bonded by DDS technique. Group (C) were prepared in dentin (1 mm) depth of preparation and their veneers were bonded by IDS technique. Standard preparation for each tooth in the experimental groups with ceramic veneer set burs especially designed for laminate veneer preparation. All the experimental groups were restored with the same type of veneer which was lithium disilicate ceramic CAD/CAM blocks (IPS e. max CAD, ivoclar vivadent) and were milled by CAD/CAM technology (CEREC inLab 4.02 milling system, Sirona).For all the experimental groups, Choice™2 veneer cement (Bisco, USA) was used for the luting of veneers. After cementation, teeth were stored in distilled water in 37°C for one week. The specimens were loaded to failure using instron universal testing machine. Specimens in experimental groups were examined by stereomicroscope at magnification of 20x to evaluate the mode of failure.Results were statistically analyzed and showed that the highest mean of failure load was recorded for the control group (548.1 N ± 93.2), for group (A) the mean of failure load was (393.4 N ± 84.2), and for Group (B) had the mean of failureAbstract IIIload was (237.8 N ± 91.6), and for group (C) the mean of failure load was (318 N ± 82.2).The one way ANOVA test was carried out and showed that there is a statistically high significant difference among the groups.Then the LSD test have shown that there is a statistically high significant difference between the control group and all three of the experimental groups, and there was a statistical high significant difference between group (A) and group (B), while group (C) have shown that there is a statistical significant difference with groups (A) and (B).The mode of failure varied from only debonding in groups (B and C) to deboning and fracture in group A.In conclusion, this study found that although enamel is still the most favorable tooth substrate for indirect adhesive restorations, the development of bonding techniques like IDS made dentin as acceptable tooth substrate for indirect adhesive restorations when it's unavoidable.
