Clinical Evaluation of CAD/CAM-generated Composite Inlays: Three-year Report

Experimental Methods: Two trained clinicians placed 40 porcelain (Vita Mark II/Vita) and 40 composite (Paradigm MZ100/3M-ESPE) CAD/CAM inlays, in 43 patients, divided between 37 molars and 43 bicuspids. A CAD/CAM unit (Cerec 2/Sirona) was used to fabricate all restorations using COS 1.21 software. Following computergraphic design of the inlay, the prefabricated block to be used for the specific restoration was randomly assigned. Both restorative materials were cemented with a total etch technique using Single Bond (3M-ESPE) and a dual cured resin cement (RelyX-ARC Resin Cement/3M-ESPE).

Results: Tooth sensitivity was evaluated by report to cold stimulus (number of teeth): 1 week: Composite (0), Porcelain (1), with no sensitivity reported in either group after 2 weeks, 6 months, 1 year, 2 years, and 3 years. All restorations were evaluated by two examiners using a modified USPHS rating. The percentage alpha scores (baseline, 6 months, 1 year, 2 years, 3 years) were: margin adaptation - Composite (100, 97, 91, 68, 66), Porcelain (97, 92, 76, 73, 65); inlay fracture - Composite (100, 100, 100, 97, 100), Porcelain (97, 94, 89, 91, 88); color match - Composite (100, 97, 97, 91, 91), Porcelain (85, 58, 65, 58, 59); margin discoloration – Composite (100, 100, 91, 91, 88), Porcelain (100, 100, 100, 91, 91). The percentage of alpha scores for anatomic form, tooth fracture, caries, and surface finish were 95% or greater for both materials at all recall intervals.

Conclusions: The composite inlays performed equally as well as the porcelain inlays at 3 years in all categories with clinical advantages noted in inlay fracture and color match. Supported by 3M/ESPE.