INTRODUCTION: No studies on the marginal gap or internal fit of crowns have reported the effect of non-axial seating which may often occur inadvertently clinically.AIM: Therefore thisin vitrostudy sought to investigate the off-axis seating of CAD/CAM crowns and its effect on the marginal gap and internal fit.METHOD: A standardised crown preparation on a typodont tooth was used to design and mill 30 crowns with a flat occlusal surface. Ten Zirconia (Dentsply Sirona, Germany), 10 Enamic (Vita, Austria), and 10 Brilliant Crios (Coltene, Switzerland) crowns were milled, Ave of each milled with a luting space of 100µm, and Ave of 200µm. The marginal gap was measured in two and three dimensions after luting with silicone on a 3D-printed metal replica. Seating occurred axially, at 5° buccally and 5° lingually. The silicone was used to calculate the internal fitRESULTS: Axial seating with a 100 µm luting space obtained the smallest marginal gap, irrespective of material or luting space. 3D measurements were larger than 2D measurements, but not significantly. The maximum off-axis gap was 117µm, on the opposite side to which pressure was applied.CONCLUSIONS: Care must be taken clinically to ensure that luting takes place in an axial direction only.
The effect of off-axis seating on the marginal adaptation of full coverage all ceramic crowns
2020-07-31
doi:10.17159/2519-0105/2020/v75no6a3
South African Dental Journal; Vol 75 No 6 (2020): South African Dental Journal; 303-310 ; 2519-0105 ; 0375-1562
Article (Journal)
Electronic Resource
English
DDC: | 629 |
Seating: Better seating justifies investment
British Library Online Contents | 2006
Seating systems, seating-system kits, and methods of configuring seating systems
European Patent Office | 2020
|Modular vehicle seating insert, modular seating system and modular seating method
European Patent Office | 2020
|MODULAR VEHICLE SEATING INSERT, MODULAR SEATING SYSTEM AND MODULAR SEATING METHOD
European Patent Office | 2019
|