Comparison of fracture resistance and failure pattern of endodontically treated premolars with different esthetic onlay systems: An in vitro study

Abstract

Aim:To compare the fracture resistance and modes of failures of three different aesthetic MOD onlays on endodontically treated premolars.Materials and Methods:Forty sound maxillary premolars were selected of which 10 untreated teeth were taken as control (Group I). The other thirty premolars were subjected to standardized MOD onlay preparations and root canal treatments and divided into 3 equal groups. Onlays were prepared in Group II- Indirect composite, Group III- Lithium Disilicate ceramic and Group IV- Full Zirconia. All onlays were cemented using Multilink Automix. All the 40 samples were subjected to fracture resistance testing on Universal testing machine. Also fractured specimens were observed under stereo-microscope for modes of failure.Results:Group IV presented the highest fracture resistance. Groups II and III presented no significant difference in fracture resistance from each other (P > 0.05). Group II and Group III showed significantly lower fracture resistance values than Group I. Coming to modes of failure, only Group IV had showed no cracks in any of the restorations.Conclusion:Full Zirconia MOD onlays increased the fracture resistance of endodontically treated premolars to a significantly higher level than the sound teeth.

Effect of Direct Composite and Indirect Ceramic Onlay Restorations on Fracture Resistance of Endodontically Treated Maxillary Premolars

“…The first layer of the P60 composite was applied at 2 mm from the orifice and cured for 20 seconds. Then, the composite was incrementally applied and cured for 20 seconds with an overlapping curing procedure in the pulp chamber as shown in Figure 1 [ 2 , 5 ].…”

“…Survival of endodontically treated teeth depends on the amount of remaining tooth structure, type of restorative material, the technique of tooth restoration, and interactions between teeth, restorative materials, and the oral environment [ 4 ]. Many dental clinicians have often recommended complete coverage of endodontically treated teeth by prosthetic crowns [ 5 ]. However, inlay and onlay restorations can also be used in certain cases.…”

“…However, inlay and onlay restorations can also be used in certain cases. Indirect restorative materials commonly used for the fabrication of inlays, onlays, and crowns include lithium disilicate, which has a high translucency and a wide color spectrum, as well as indirect composite resins, which have been proven to increase the fracture resistance of teeth [ 5 ].…”

“…On the other hand, ceramics have higher compressive resistance and durability than composite restorations in the oral cavity [ 6 ]. However, there are some controversies in this respect [ 5 ].…”

Effect of different adhesive strategies on microtensile bond strength of computer aided design/computer aided manufacturing blocks bonded to dentin

“…The newly emergent leucite glass ceramic and lithium disilicate ceramic blocks are gaining popularity due to better mechanical and aesthetic properties when compared to the feldspathic ceramic. [ 11 12 13 ] In addition to ceramic materials, CAD/CAM restorations also can be milled from composite blocks[ 4 ] and from a hybrid of composite resin and ceramic. [ 14 ] The ceramic blocks are manufactured by Vita and are a mixture of 30% by weight feldspathic crystalline particles embedded in a glassy matrix.…”