Veneer

AIM: The aim of this study was to evaluate the physical-mechanical behavior of the occlusal veneers when subjected to thermomechanical cycling. MATERIALS AND METHODS: Sixty specimens were divided into 04 groups (n=15 per group), according with the different restorative materials and thicknesses: material - lithium dissilicate LD (IPS e.max CAD, Ivoclar Vivadent) and nano- ceramic-resins NCR (ESPE Lava Ultimate, 3M); thickness - 0.6 and 1.2mm. The occlusal veneers were bonded over human flattened fresh extracted molars with dual-polymerizing luting agent (Variolink N, Ivoclar Vivadent and RelyX Ultimate 3M) using the respective adhesive system following the selective-etch technique (self-etch in dentin and total etch in enamel)...

BACKGROUND: 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. Samples were divided into four groups according to surface treatment: Group (A) air abraded with 110 μm Al2 O3 , Group (AP) air abrasion and primer application, Group (S) 98% sulfuric acid etching for 60 s, Group (SP) Sulfuric acid and primer...

BACKGROUND: Impressions that maintain their dimensional stability after autoclaving effectively control cross-infection and contamination resulting from a patient's oral secretions. PURPOSE: The study aimed to assess the dimensional stability of autoclavable polyvinyl siloxanes after disinfection and sterilization. METHODS: A stainless steel metal model containing three full veneer crown preparations was fabricated according to ANSI/ADA specification No...

BACKGROUND: The screw-retrievable cement-retained (SRCR) design combines the benefits of both screwand cement-retained implant-supported restorations. This concept has sparked interest in implant dentistry. However, there is a lack of research on fracture behaviors and clinical performance of such restorations. OBJECTIVES: The aim of the present article was to review the current literature on the fracture loads and fracture modes of SRCR implant restorations - in vitro studies, and also studies demonstrating the clinical performance of such design...

The objective of this case report was to provide a plan for aesthetic rehabilitation of a patient utilizing layered zirconia restorations to produce a homogeneous, pleasing smile. In this case, a female patient, aged 38 years, presented in dental clinic with a spaced dentition and faulty crowns that were causing functional and aesthetic concerns. She was a banker by profession and socially active. The treatment plan involved layered zirconia indirect restorations to enhance her natural teeth appearance. The aim of this case report was to propose an effective strategy for addressing her concerns, with the potential to achieve a desired aesthetic outcome...

This study aimed at examining the bond strength between zirconia and ceramic veneer, following the ISO 9693 guidelines. A total of fifty specimens of zirconia/ceramic-veneer system were produced using two commercial zirconias (VITA YZ-HTWhite and Zolid HT+ White, referred to as Group A and Group B, respectively) and a ceramic-veneering material (Zirkonia 750). The microstructure (via x-ray diffraction analysis, XRD) and the mechanical properties (via 3-point bending tests) of the two groups were assessed. Then, experiments were conducted according to the ISO 9693 and conventional protocols applied for producing zirconia/ceramic-veneer restorations...

The need, or even the obligation, to take care of the natural environment compels a search for new technological solutions, or for known solutions to be adapted to new applications. The maxim is 'don't harm, but improve the world for future generations'. In the wood industry in particular, given that it is based on a natural raw material, we must look for ecological solutions. Trees grow, but the demand for wood exceeds the volume of tree growth. In industrial manufacturing, one of the ways to make full use of wood is through chipless processing, which occurs during rotary cutting (peeling)...

Tooth autotransplantation is one of the methods used for tooth loss rehabilitation in children. Premolars are usually used as autotransplants requiring esthetic alterations. The purpose of this paper is to present an innovative, alternative and inexpensive way to restore auto-transplanted teeth using the crown of the tooth of the recipient site. A seven-year-old male with a non-contributory medical history presented with an intrusion of his permanent maxillary right central incisor. The tooth underwent orthodontic extrusion using fixed appliances but eventually showed signs of ankylosis...

BACKGROUND: Restorative materials might significantly affect load transmission in peri-implant bone. The aim of the present study is to evaluate the shock absorption capacity of two different polymeric materials to be used for implant-supported prostheses. METHODS: A masticatory robot was used to compare the shock absorption capacity of veneered and non-veneered polyetherketoneketone (PEKK), Pekkton® ivory (Cendres+Mètaux), and the glass fiber-reinforced composite (GFRC), TRINIATM (Bicon)...

OBJECTIVES: This study aimed to assess the influence of translucent monolithic versus bilayered crowns and whether the use of a CoCr base abutments affects the fatigue and fracture resistance of screwed implant-supported single crowns with external connections under mechanical cycling. MATERIALS AND METHODS: Fifty specimens were divided into groups: (1) metal-ceramic (MC) crown, (2) veneered zirconia crown (Zr), (3) veneered zirconia crown with a CoCr base abutment (ZrB), (4) monolithic translucent zirconia crown (MZr), and (5) monolithic translucent zirconia crown with a CoCr base abutment (MZrB)...

PURPOSE: To investigate the in vitro biocompatibility of human gingival fibroblasts with preformed paediatric crowns and resistance to acid exposure at levels that simulate the oral environment. METHODS: This laboratory study investigated primary HGFs viability, metabolic activity, cytotoxicity, and apoptotic events on preformed metal crown discs, composite resin-coated wells, and monolithic zirconia fragments at 24, 48, and 72 h using the ApoTox-Glo Triplex assay...

AIM: The main aim of the present study was to compare and evaluate the effect of repetitive firings on different shades of a pressable all ceramic system layered with veneering porcelain. SETTING AND DESIGN: In-vitro comparative study. MATERIALS AND METHODS: An in vitro comparative study was conducted, and a total of 60 disc shaped specimens (15 mm in diameter and 0.8 mm in thickness) were made of heat pressed ceramic of shades A2, A3, and B2 (20 discs of each shade) grouped as Group I, II, and III, respectively, using the lost wax technique...

A method to more easily separate vascular bundles and parenchyma was investigated for the purpose of proposing a sustainable and advanced utilization of oil palm trunk (OPT). In addition, particleboard made from vascular bundles was produced as one of the effective ways to utilize the obtained vascular bundles. The following results were obtained. A Zephyr rolling equipment was used for separation, and it was found that the vascular bundles could be easily separated with the veneer in a dry state. SEM observations showed that the vascular bundles could be separated while maintaining the tissue structure...

PURPOSE: The aim of the current study was to evaluate the effect of simulated gastric acid on the color and translucency of different indirect restorative materials. MATERIALS AND METHODS: A total of 36 disc-shaped samples were cut by using an isomet saw and divided into four equal groups (n = 9) according to the material type: Group Z: translucent zirconia (Ceramill® Zolid ht.+ preshade, Amann Girrbach, Koblach, Austria); Group E: lithium disilicate (IPS e...

The present article reviews the literature regarding tetracycline staining of the dentition and its esthetic management. A total of 49 articles were identified in the initial search, and 22 articles met the eligibility criteria of this narrative literature review. Tetracycline staining results from its use in children between the ages of 6 months and 6 years, when tooth crowns are formed; the effects are dependent on the dosage, duration of treatment, stage of tooth mineralization, and activity of the mineralization process...

INTRODUCTION: The acquisition of skills and manual dexterity in aesthetic dentistry in undergraduate teaching requires preclinical practices with simulation that should approximate real clinical situations. OBJECTIVE: We will present a digital procedure for the creation of three-dimensional (3D) resin models adapted to the practices of the Aesthetic Dentistry course. MATERIAL AND METHOD: Stereolithography or Standard Tesellation Language (STL) files of a real patient were previously obtained with a 3-shape intraoral scanner...

BACKGROUND: Marginal fit significantly impacts the long-term success of dental restorations. Different pattern fabrication methods, including hand-waxing, milling, or 3D printing, may affect restorations accuracy. The effect of porcelain firing cycles on the marginal fit of metal-ceramic restorations remains controversial, with conflicting findings across studies. PURPOSE: The aim was to evaluate the potential effects of multiple porcelain firings (3, 5, 7 cycles) as well as pattern fabrication method (conventional hand-waxing, milling, and 3D printing) on the marginal adaptation of 3-unit implant-supported metal-ceramic fixed partial dentures...

BACKGROUND: Self-glazed zirconia (SZ) restorations are made by a novel additive three-dimensional gel deposition approach, which are suitable for a straightforward completely digital workflow. SZ has recently been used as minimally invasive veneer, but its clinical outcomes have not been clarified yet. This study aimed to evaluate the preliminary clinical outcomes of SZ veneers compared with the widely used lithium disilicate glass-ceramic veneers made by either pressing (PG) or milling (MG) process...

Waterborne acrylic coatings, the largest market share of predominant environmentally friendly coatings, face limitations in their extensive application due to their flammability. The flame-retardant properties of the coatings could be significantly enhanced by incorporate inorganic flame retardants. However, inorganic flame retardants tend to aggregate and unevenly disperse in waterborne acrylic coatings, causing a substantial decrease in flame retardancy. In this work, sodium silicate was utilized as a flame retardant, with urea and melamine serving as modifiers and synergistic agents...

Molded plywood is used for furniture components such as seats, backrests, or integral seat shells, and it must be durable and harmless to health. Molded plywood is made with urea-formaldehyde (UF) adhesives; therefore, the issue of the fillers used in them is important. The potential of using ground beech ( Fagus sylvatica L.) bark as an eco-friendly additive in UF adhesives for molded plywood manufacturing was investigated in this work. Wheat flour was used as a reference filler. The beech bark (BB) level as a filler was 10%, a value verified under laboratory conditions...