introduction: marginal adaptation is the most critical item in long-term prognosis of single crowns. this study aimed to assess the marginal quality as well asthe discrepancies in marginal integrity of some pfm single crowns of posterior teeth by employing parallel radiography in shiraz dental school, shiraz, iran. methods: in this descriptive study, parallel radiographies were taken from 200 f...

The most general form of a marginal extended perturbation in a two– dimensional system is deduced from scaling considerations. It includes as particular cases extended perturbations decaying either from a surface, a line or a point for which exact results have been previously obtained. The first–order corrections to the local exponents, which are functions of the amplitude of the defect, are de...

PURPOSE This study evaluated marginal fit of glass infiltrated alumina cores fabricated using two techniques and their marginal stability after firing cycles of veneering porcelain. MATERIALS AND METHODS Fifteen standardized all-ceramic crowns were fabricated on a metal die using each technique: slip cast technique of VITA In-Ceram sprint Alumina (Group A as control) and plastic foil matrix t...

the aim of this study was to evaluate the marginal adaptation of biodentine in comparison with mineral trioxide aggregate (mta) and intermediate restorative material (irm), as a root end filling material, using scanning electron microscopy (sem).thirty permanent maxillary central incisors were chemo-mechanically prepared and obturated. three millimetres of the root end were resected and 3mm ret...

PURPOSE To evaluate the clinical performance of inlays and onlays luted with two different resin cements, mixed at different temperatures and to evaluate the marginal adaptation of the restorations. MATERIALS AND METHODS One hundred IPS e.max restorations (82 onlays, 18 inlays; 84 molars, 16 premolars) were placed in 50 patients (28 females, 22 males, mean age, 33 years). The restorations wer...

Introduction – Shrinkage during polymerization of resin-based composite materials may lead to gap formation and hamper the marginal adaptation of the restorations. To reduce the problem of polymerization shrinkage, a new composite material (FiltekTM Silorane, 3M-ESPE, Germany), with a reduced shrinkage, has been marketed. Objective – To investigate whether reduced polymerization shrinkage impro...

PURPOSE The purpose of this study was to evaluate the effect of the span length on the fit of zirconia framework fabricated using CAD/CAM system. MATERIALS AND METHODS Abutments for single, 4-unit and 6-unit fixed partial prostheses were fabricated. Ten zirconia frameworks were fabricated for each group. The marginal and internal gap were presented by means of replica technique and measured b...

Aims: This study was aimed to compare the effect of three different pattern materials on the vertical marginal discrepancy of Nickel-Chromium copings fabricated on titanium implant abutments. Methods: A titanium implant abutment was used to receive 30 Nickel-Chromium copings. The copings were constructed using pattern wax (group 1), acrylic pattern resin (group 2), and lightcured pattern resin ...

Objectives: To evaluate the microleakage and marginal gap of various luting materials after cementing ceramic crowns. Methods: Cervical margins of human molars were designed as circular chamfers. Cementation of full-contour ceramic crowns was conducted with zinc-phosphate cement (Harvard cement), resin cement (Panavia F 2.0) and self-adhesive resin cements (RelyX Unicem, BifixSE, MaxCem Elite, ...

OBJECTIVES The purpose of this in vitro study was to compare the marginal adaptation and fracture resistance of a zirconia-based all-ceramic restoration with two preparation designs. MATERIALS AND METHODS Twenty-four mandibular premolars were randomly divided into two groups (n=12); the conventional group received a peripheral shoulder preparation and the modified group received a buccal shou...