Publications by authors named "Marwa Wahsh"
Purpose: The objective of this study was to evaluate the effect of (Er,Cr: YSGG) laser debonding treatment on optical properties and surface roughness of veneers made of different ceramic materials.
Materials And Methods: Thirty bovine incisors were prepared to receive laminate veneers and divided into three groups (n = 10) according to ceramic material where group (E): IPS e.max CAD, group (S): Vita Suprinity, and group (C): Celtra Duo.
Background: Erbium lasers safely offer the possibility of reuse for debonded restorations. Since these lasers have a high affinity for water molecules, they are absorbed by resin cement causing explosive ablation of the cement and thus, the restoration debonds. The efficiency of this process depends on many factors, including the ceramic type, its chemical composition and thickness.
View Article and Find Full Text PDFBackground: This study aims to evaluate the effect of surface treatment and resin cement on the shear bond strength (SBS) and mode of failure of polyetheretherketone (PEEK) to lithium disilicate ceramic (LDC). This is suggested to study alternative veneering of PEEK frameworks with a ceramic material.
Methods: eighty discs were prepared from PEEK blank and from lithium disilicate ceramic.
Background: Polyetherketoneketone (PEKK) was recently introduced as an alternative to titanium and ceramic implant abutments due to its apparent ability to dissipate excessive strain around dental implants. However, the biomechanical behaviors of implant abutment crown systems may change depending on the crown and abutment material combinations used.
Objectives: This study aimed to assess how the crown material affects strain generation and fracture resistance of PEKK hybrid abutment crowns.
Objectives: Evaluating the bond strength of two ceramic materials to dentin after Er,Cr:YSGG laser debonding. Would laser debonding affect the bond strength of ceramic to dentin?
Materials And Methods: Recently extracted human molars were ground to expose dentin. Forty square shaped samples were prepared from CAD/CAM ceramic blocks.
Statement Of Problem: High-performance polyetheretherketone (PEEK) has been used in dentistry because of its excellent physical and chemical properties. However, its lack of translucency requires the use of a veneering composite resin for esthetic applications. Data on bonding a veneering composite resin to PEEK are still scarce.
View Article and Find Full Text PDFPurpose: To evaluate the effect of three two-retainer designs of a resin-bonded fixed dental prosthesis (RBFDP) on fracture resistance.
Materials And Methods: A total of 21 three-unit, all-ceramic RBFPDs were fabricated to replace a missing maxillary lateral incisor. The prostheses were divided into three groups of 7 each: Group L (labial RBFPD); Group ML (modified labial RBFPD, fabricated the same as in Group L with additional preparation that included a shallow proximal groove at the pontic side); and Group P, an all-ceramic palatal RBFPD that acted as control.
Objective: This in vitro study was conducted to assess the marginal adaptation and fracture resistance of computer aided design/computer aided manufacturer (CAD-CAM) fabricated endocrowns restoring endodontically treated molars using different machinable blocks with thermomechanical loading protocols.
Materials And Methods: Devitalized mandibular molars were prepared in a standardized way and divided into 4 groups (n = 10) to receive CAD/CAM fabricated endocrowns using four materials (Lithium disilicate ceramics, polymer infiltrated ceramics, zirconia-reinforced lithium silicate ceramics and resin nanoceramics. Marginal gaps (µm) were measured using stereomicroscope before cementation and after cementation.
Bond strength of resin cement to zirconia treated in pre-sintered stage.
J Mech Behav Biomed Mater
October 2018
Purpose: Aim of this study was to evaluate the tensile bond strength (TBS) between resin cement and zirconia surface treated in different sintering stages.
Materials And Methods: Eighty zirconia discs having final dimensions of 12 mm diameter and 3.2 mm thickness were milled then divided into three main groups according to the type of surface treatment performed (group 1: air abrasion using 50 µm AlO particles, group 2: silica coating using Rocatec soft, and group 3: a control group receiving no surface treatment).
Purpose: The purpose of this in vitro study was to assess the effect of varying the margin designs and the occlusal thicknesses on the fracture resistance and mode of failures of endodontically treated teeth restored with polymer infiltrated ceramic endocrown restorations.
Methods: Root canal treated mandibular molars were divided into four groups (n=8) and were prepared to receive Computer-Aided Design/Computer-Aided Manufacturing (CAD/CAM) fabricated polymer infiltrated ceramic endocrowns (ENAMIC blocks). Group B2 represents teeth prepared with a butt joint design receiving endocrowns with 2mm occlusal thickness and the same for group B3.
Purpose: This study evaluated the effect of surface treatment of zirconia in pre-sintered and post-sintered stages on its surface roughness, phase transformation, and biaxial flexural strength (BFS).
Methods: Zirconia ceramic discs (n=40) having a final dimensions of 12mm diameter and 1.2mm thickness were milled then divided into three main groups according to the type of surface treatment performed (Group 1 (n=16); air-abrasion using AlO particles, Group 2 (n=16); silica coating using Rocatec soft, and Group 3 (n=8); a control group receiving no surface treatment).