CAD/CAM Zirconia vs. slip-cast glass-infiltrated Alumina/Zirconia all-ceramic crowns: 2-year results of a randomized controlled clinical trial

Abstract

The aim of this randomized controlled clinical trial was to compare the early clinical outcome of slip-cast glass-infiltrated Alumina/Zirconia and CAD/CAM Zirconia all-ceramic crowns. A total of 30 InCeram® Zirconia and Cercon® Zirconia crowns were fabricated and cemented with a glass ionomer cement in 20 patients. At baseline, 6-month, 1-year, and 2-year recall appointments, Californian Dental Association (CDA) quality evaluation system was used to evaluate the prosthetic replacements, and plaque and gingival index scores were used to explore the periodontal outcome of the treatments. No clinical sign of marginal discoloration, persistent pain and secondary caries was detected in any of the restorations. All InCeram® Zirconia crowns survived during the 2-year period, although one nonvital tooth experienced root fracture coupled with the fracture of the veneering porcelain of the restoration. One Cercon® Zirconia restoration fractured and was replaced. According to the CDA criteria, marginal integrity was rated excellent for InCeram® Zirconia (73%) and Cercon® Zirconia (80%) restorations, respectively. Slight color mismatch rate was higher for InCeram® Zirconia restorations (66%) than Cercon® Zirconia (26%) restorations. Plaque and gingival index scores were mostly zero and almost constant over time. Time-dependent changes in plaque and gingival index scores within and between groups were statistically similar (p>0.05). This clinical study demonstrates that single-tooth InCeram® Zirconia and Cercon® Zirconia crowns have comparable early clinical outcome, both seem as acceptable treatment modalities, and most importantly, all-ceramic alumina crowns strengthened by 25% zirconia can sufficiently withstand functional load in the posterior zone.

Three- to nine-year survival estimates and fracture mechanisms of zirconia- and alumina-based restorations using standardized criteria to distinguish the severity of ceramic fractures

“…According to these studies, fractures of the veneer requiring replacement of the crowns were few and ranged between 0 and 1.9 % at 2-5 years. Only one fracture of the zirconia core was reported [12]. Current clinical studies on zirconia-based multiunit FDPs [18][19][20][21] confirm previous systematic reviews [4][5][6]: chipping of the veneering ceramic was a frequent complication, whereas fractures of the core only seldom occurred.…”

“…Clinical data on zirconia-based SCs are scarce. In short-term studies, failure rates ranged from 0 to 11.2 % at 2-5 years [12][13][14][15][16][17]. However, the rates of "biological" and "other complications" were not specified relative to "fractures of the ceramic" [13,17].…”

The effect of prosthetic margin location on caries susceptibility. A systematic review and meta-analysis

“…Twenty-two studies were finally included in the qualitative synthesis. 26,27,[33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52] Inter-reviewer agreement during the second review phase ranged from 'substantial agreement' to 'almost perfect agreement' (kappa: 0.715 -0.933) ( Table 2). The flowchart of the results and the review process according to the PRISMA statement is provided in Figure 1.…”

Reliability of reduced-thickness and thinly veneered lithium disilicate crowns

“…Although zirconia fixed partial dentures have been most commonly investigated (Tinschert et al, 2005;Vult von Steyern et al, 2005;Sailer et al, 2006), the sparse information regarding single crowns has shown similar results concerning the principal failure mode, which involved fractures within the veneering ceramic (Cehreli et al, 2009;Ortorp et al, 2009;Groten and Huttig, 2010). A method to reproduce these failure modes in the laboratory has been developed using mouth-motion fatiguetesting in water (Coelho et al, 2009a,b;Silva et al, 2010), where mechanical testing has confirmed the susceptibility of zirconia crowns to porcelain veneer failure.…”