Stress distribution of Class V composite resin restorations: A three-dimensional finite element study

Abstract

This study was to investigate the influence of composite resins with different elastic modulus, cavity modification and occlusal loading condition on the stress distribution of restored notch-shaped noncarious cervical lesion using 3-dimensional (3D) finite element (FE) analysis.The extracted maxillary second premolar was scanned serially with Micro-CT. The 3D images were processed by 3D-DOCTOR. ANSYS was used to mesh and analyze 3D FE model. A notch-shaped cavity and a modified cavity with a rounded apex were modeled. Unmodified and modified cavities were filled with hybrid or flowable resin. After restoration, a static load of 500N was applied in a point-load condition at buccal cusp and palatal cusp. The stress data were analyzed using analysis of principal stress.The results were as follows: 1. In the unrestored cavity, the stresses were highly concentrated at mesial CEJ and lesion apex and the peak stress was observed at the mesial point angle under both loading conditions. 2. After restoration of the cavity, stresses were significantly reduced at the lesion apex, however cervical cavosurface margin, stresses were more increased than before restoration under both loading conditions. 3. When restoring the notch-shaped lesion, material with high elastic modulus worked well at the lesion apex and material with low elastic modulus worked well at the cervical cavosurface margin. 4. Cavity modification the rounding apex did not reduce compressive stress, but tensile stress was reduced. [J Kor Acad Cons Dent 33(1):28-38, 2008] Key words : Cervical lesion, class V lesion, composite resin, finite element analysis, stress distribution

Clinical Evaluation of Bioactive Restorative Material versus Resin Modified Glass Ionomer in Cervical Restorations: A Randomized Controlled Clinical Trial

“…Regarding this study, marginal discoloration results showed there are two restorations scored Bravo in the control group while three restorations scored bravo in the intervention group after 12 months with no significant difference between the restoration groups (p = 0.791), but there was a significant difference within ACTIVA group over the time (p = 0.05). This result is in acceptance with Park et al (2008) who attributed the difficulty of bonding to class V cavity to high flexural stresses on restoration that cause debonding [6]. Moreover, general difficulty in dentin bonding due to its heterogeneous structure, inherited wetness, collagentic activity of MMPS, and cysteine cathepsins.…”

“…Cervical lesions restorations are posing a challenge to the dental profession [6]. Cervical adhesive restorations failure is often attributed to inadequate moisture control, adhesion to different opposite substrates (enamel and dentin), differences in dentin composition, and great flexural stresses acting on the restoration that may lead to early loss or fracture [7].…”

Finite element analysis of maxillary central incisors restored with various post-and-core applications

“…If the modulus of elasticity of the core material is similar to the post material, a more uniform stress distribution within the entire post-and-core restoration and within dentin is achieved, while the restoration' s resistance is increased against the high forces of mastication 27,28) . As with many in vitro studies, it is difficult to extrapolate the results of this study directly to a clinical situation 29) . For example, the finish line and ferrule were placed at a constant height around the periphery of the teeth.…”

Effect of restoration type on the stress distribution of endodontically treated maxillary premolars; Three-dimensional finite element study

“…Stress analysis was focused at the CEJ area of buccal and palatal surface based on the reports of many FEA studies 12,[23][24][25] . Kuroe et al 26) also confirmed by the photoelastic method that a vertical force loaded on the tooth causes stress concentration at the cervical line.…”