Fracture Resistance of Restored Maxillary Premolars

Abstract

Extensively damaged teeth can be restored by different core build-up materials. The aim of this study was to examine the fracture resistance of restored maxillary premolars with composite resin, dental amalgam and glass ionomer cement (GIC) using compressive strength test. Also, to analyse the influence of bond strength of restorative materials on intact and carious dentin. Eighty extracted human maxillary premolars with intact and carious dentin were used in the study. The control group consisted of ten unrestored teeth with intact dentin. Artificial defect in dentin was prepared using diamond bur up to the half of the anatomic crown of the tooth. After core build-up procedure, each specimen was mounted in auto polymerizing acrylic resin blocks 2mm below cement enamel junction and they were kept in distilled water at 37 o C one day before testing. Then, they were placed in specially adapted devices at an angle of 183 o to the longitudinal axis and subjected to a controlled load of 1mm per minute. There were significant differences among control group and restored teeth with composite resin, amalgam and GIC. Results showed that the best fracture values were obtained in control group (749,4N , then intact teeth restored with composite resin (492,5N) and amalgam (341,2N). In the group with carious dentin, values were lower, for composite resin 345,5 N and for amalgam 474,5N. There were no significant differences among restored groups with intact and carious dentin (p<0.05). The fracture force corresponding to the teeth restored with GIC were significantly lower compared to the control group and the group with composite resin and amalgam. Satisfactory mechanical properties of restored premolars were obtained using composite resin and dental amalgam as a core build-up material. The carious-affected dentin led to lower bond strength of restored teeth.

Comparative evaluation of shear bond strength of three resin based dual-cure core build-up materials: An In-vitro study

“…The present study was done in-vitro , as the clinical functions and characteristics of dental materials are difficult to evaluate under in-vivo conditions, and clinical trials cannot estimate mechanical properties of restored teeth. [ 12 ] Whereas, in-vitro tests give the possibility to evaluate mechanical properties of restored teeth,[ 13 ] and are considered as a predictor of the possible clinical performance of a material. [ 14 ]…”

Composition-structure-property relationships for non-classical ionomer cements formulated with zinc-boron germanium-based glasses

“…7,8 Yet, despite the advantages of GICs, their poor wear resistance and low fracture strength limit their applications to areas such as non-occlusal load-bearing single-surface restorations, 9 linings for composites restorations, 10 and as core-build-up materials for crown placements. 11 Although GICs are synonymous with cariostatic capabilities (principally associated with fluoride release), the literature has noted that there is “no difference in the caries-preventive effect of GIC and resin-based fissure sealant material(s)”. 12 In addition to their limited mechanical properties, this is a point of significant consequence, since dental caries is the most prevalent non-communicable disease in the world and affects between 60% and 90% of school children and the vast majority of adults.…”

Study of the Mechanical Properties of the Novel Zirconia-reinforced Glass Ionomer Cement

“…2 This is limited if the strength of restorative materials is close to the strength of the tooth structure. 3 Thus, the quest for an ideal restorative material with optimum physical properties and durability exists. Since the 1890s, amalgam -a metallic restorative material obtained by combining mercury and mixture of silver, tin, and copper alloy 4 -was widely chosen for such restorations by dental practitioners because of its high compressive strength (CS) (380−540 MPa) and tensile strength (57 MPa), durability, longevity, and marginal integrity of the material; moreover, there was lack of availability and development in the field of restorative materials.…”