Omayma Tantawy Sayed , Cherif Adel Mohsen And Shams Waaz Amgd,

ABSTRACT
The Aim Of This Study Is To Evaluate The Marginal Leakage And Internal Adaptation Of Porcelain Laminate Veneer Using Two Different Types Of Ceramics (pressable And Machinable CAD/CAM).

Materials and Methods: 40 Ceramic Laminate Veneers Were Fabricated By Two Different Fabrication Technique Using A Conventional Pressable Technique (group P N = 20) And A CAD/CAM Fabrication Technique (group M N = 20). All Samples Were Prepared(overlap Preparation), Then Transferred Into Epoxy Samples Then Veneers Were Fabricated, And All Samples Were Cemented Under The Same Condition. All Specimens Were Stored Under Water (37?C) For 60 Days, Then Received Thermocycling Followed By Cyclic Loading, Then Samples Immersed In Methylene Blue Dye For 24 H. Half Of The Specimens In Each Group Were Sectioned In Vertical Direction (n = 20), And The Rest Were Horizontally Sectioned (n = 20). Internal Adaptation, And Marginal Gaps At The Incisal And Cervical Regions Were Measured.

Results: Pressable Ceramic Veneers Demonstrated Significantly Higher Vertical And Horizontal Marginal Gaps At The Cervical And Incisal Margins And Lower Cement Film Thickness (F = 50.921, P < 0.001) Compared To Machinable Ceramic Veneers. The Machinable Ceramic Veneers Were Associated With Significantly Lower Marginal Leakageleakage Values.

Conclusions: Machainable Ceramic Laminate Veneers Produced Higher Marginal Adaptation, And Thinner Cement Film Thickness, And Improved Resistance To Microleakage Compared To Pressable Ceramic Veneers. Clinical Significance: Dentist And Laboratory Technicians Have To Choose The Manufacturing Process With Careful Consideration, As It Influences Internal And Marginal Fit Of Ceramic Veneers And The Terminal Success Of The Restoration.