Mid-term survival and complications of double-crown-retained removable dental prostheses placed in the dental practice - a retrospective study.

Objectives: Clinical data on the performance of double-crown-retained removable dental prostheses (dcRDPs), especially beyond university studies, are rare. The objective of this retrospective clinical study was to evaluate the survival and complication-freeness probabilities of dcRDPs and to identify risk factors for failure and complications in a dental practice setting.

Materials And Methods: Anonymized practice data of 174 patients (56.

Prospective clinical study of enamel wear caused by monolithic zirconia resin-bonded inlay-retained and wing-retained fixed partial dentures over 5 years.

Objectives: To prospectively evaluate the wear of posterior zirconia resin-bonded fixed partial dentures (RBFPDs) with polished occlusal surfaces and their natural enamel antagonists compared to contralateral controls in an enamel-enamel contact over 5 years.

Materials And Methods: In six patients with either an inlay- or wing-retained RBFPD made of monolithic 3 mol% yttria-stabilized tetragonal zirconia polycrystal (3Y-TZP), wear was evaluated indirectly using baseline and annual polyvinyl siloxane impressions. Resulting gypsum models were digitized and aligned by unchanged surface areas.

Accuracy of polyether and vinylpolysiloxane impressions when using different types of 3D-printed impression trays - an in vitro study.

Objectives: To investigate dimensional accuracy of polyether (PE) and vinylpolysiloxane (VPS) impressions taken with manually fabricated and 3D-printed trays.

Materials And Methods: To evaluate impression accuracy, highly precise digital data of a metallic lower jaw model with prepared teeth (regions 34 and 36), an implant (region 47) and three precision balls placed occlusally along the dental arch served as reference. PE (Impregum, 3M Oral Care) and VPS (Aquasil, Dentsply Sirona) impressions (n = 10/group) were taken with trays fabricated using different materials and manufacturing techniques (FDM: filament deposition modeling, material: Arfona Tray, Arfona; printer: Pro2, Raise3D; DLP: digital light processing, material: V-Print Tray, VOCO, printer: Max, Asiga; MPR: manual processing with light-curing plates, material: LC Tray, Müller-Omicron) including an open implant impression.

Dimensional Accuracy of Novel Vinyl Polysiloxane Compared with Polyether Impression Materials: An In Vitro Study.

Transferring the intraoral situation accurately to the dental laboratory is crucial for fabricating precise restorations. This study aimed to compare the dimensional accuracy of a new hydrophilic quadrofunctional vinyl polysiloxane (VPS) and polyether (PE), in combination with different impression techniques (mono-phase single step or dual-phase single step). The reference model simulated a partially edentulous mandible.

Effect of wall thickness on shape accuracy of hollow zirconia artificial teeth fabricated by a 3D printer.

Purpose: This study aimed to analyze how the wall thickness of 3D-printed hollow zirconia teeth affects shape accuracy.

Methods: Datasets with measurement points were created for different artificial teeth resembling the mandibular right first molar (Geomagic Design X, 3D Systems). Reference distances were 9.

Bond Strength of Milled and Printed Zirconia to 10-Methacryloyloxydecyl Dihydrogen Phosphate (10-MDP) Resin Cement as a Function of Ceramic Conditioning, Disinfection and Ageing.

This study aimed to assess the suitability of printed zirconia (ZrO) for adhesive cementation compared to milled ZrO. Surface conditioning protocols and disinfection effects on bond strength were also investigated. ZrO discs (n = 14/group) underwent either alumina (AlO) airborne particle abrasion (APA; 50 µm, 0.

Fracture Resistance of 3D-Printed Occlusal Veneers Made from 3Y-TZP Zirconia.

The aim of this paper was to evaluate the fracture resistance of 3D-printed zirconia occlusal veneers (OVs) of different thicknesses and supported by different abutment materials. The standard OV of a natural molar was prepared and digitized using a laboratory 3D scanner. The resulting digital tooth abutment was milled either using cobalt-chromium (CoCr) or a fiber-reinforced composite (FRC).

Load-bearing capacity of 3D-printed incisor partial-coverage crowns made from zirconia and composite.

Purpose: This study investigated the fracture resistance of 0.5-mm-thick restorations for minimally invasive therapy. Anterior partial-coverage crowns composed of three-dimensional (3D)-printed 3-mol% yttria-stabilized tetragonal zirconia polycrystal (3Y-TZP; Lithacon 3Y210, Lithoz) and 3D-printed composite (Varseo Smile Crown plus, Bego) were compared with a control group made from milled 3Y-TZP (Cercon ht, DentsplySirona).

Finite Element Analysis of Fixed Orthodontic Retainers.

The efficacy of retainers is a pivotal concern in orthodontic care. This study examined the biomechanical behaviour of retainers, particularly the influence of retainer stiffness and tooth resilience on force transmission and stress distribution. To do this, a finite element model was created of the lower jaw from the left to the right canine with a retainer attached on the oral side.

Metal-Ceramic Resin-Bonded Fixed Partial Dentures After a Mean Observation Time of 7.5 Years.

Purpose: To generate data on the long-term survival of metal-ceramic resin-bonded fixed partial dentures (RBFPDs).

Materials And Methods: A total of 89 patients received 94 RBFPDs, 5 of whom (women n = 1; men n = 4) received 2 RBFPDs each. All RBFPDs were fabricated as two-retainer end-abutment metal-ceramic restorations.

Effect of a calibration aid and the intraoral scanner on the registration of a partially edentulous maxilla: An in vitro study.

Statement Of Problem: Precise data are a prerequisite for accurately fitting restorations. Therefore, intraoral scanners have to be reliable. Data on differences between the same model of intraoral scanning systems are lacking.

Biaxial flexural strength of 3D-printed 3Y-TZP zirconia using a novel ceramic printer.

Objectives: To compare the strength and reliability of 3D-printed 3Y-TZP zirconia manufactured with various printing orientations and staining.

Materials And Methods: A total of one-hundred cylindrical zirconia specimens were designed and fabricated using 3D printing and processed according to ISO 6872 standards. Of these specimens, 80 were 3D printed using the new ZIPRO-D (ZD) 3D ceramic printer.

In vitro pilot study comparing a novel implantoplasty sonic instrumentation protocol with a conventional protocol using burs.

Background And Objectives: The aim of implantoplasty (IP) is to remove titanium implant layers that have been contaminated and to smoothen the implant surfaces so they retain less plaque. However, existing IP methods are very invasive and reduce implant wall thickness.

Aim: To investigate the suitability of novel sonic tips in IP and to compare this novel protocol with conventional abrasive procedures.

Initial damage and failure load of zirconia-ceramic and metal-ceramic posterior cantilever fixed partial dentures.

Objectives: The aim of this study was to compare failure load and initial damage in monolithic, partially veneered, and completely veneered (translucent) zirconia cantilevered fixed partial dentures (CFPDs), as well as completely veneered metal-ceramic CFPDs under different support and loading configurations.

Materials And Methods: Eight test groups with anatomically congruent CFPDs (n = 8/group) were fabricated, differing in CFPD material/support structure/loading direction (load applied via steel ball (Ø 6 mm) 3 mm from the distal end of the pontic for axial loading with a 2-point contact on the inner cusp ridges of the buccal and oral cusps and 1.3 mm below the oral cusp tip for 30° oblique loading): (1) monolithic zirconia/CoCr abutment teeth/axial, (2) monolithic zirconia/CoCr abutment teeth/oblique, (3) partially veneered zirconia/CoCr abutment teeth/axial, (4) partially veneered zirconia/CoCr abutment teeth/oblique, (5) completely veneered zirconia/CoCr abutment teeth/axial, (6) completely veneered CoCr/CoCr abutment teeth/axial (control group), (7) partially veneered zirconia/implants/axial, and (8) partially veneered zirconia/natural teeth/axial.

Fracture Resistance of Posterior Tooth-Supported Cantilever Fixed Dental Prostheses of Different Zirconia Generations and Framework Thicknesses: An In Vitro Study.

The rehabilitation of free-end situations is a frequent indication in prosthetic dentistry. Cantilever fixed dental prostheses (cFDPs) made of 1st and 2nd generation zirconia are one treatment option. Due to a unique gradient technology, combinations of different zirconium dioxide generations are thus feasible in one restoration.

A German version of the Oral Impacts of Daily Performances-reliability and validity.

Objective: The Oral Impact of Daily Performances (OIDP) is a dental patient-reported outcome measure (dPROM) for the estimation of oral health-related quality of life (OHRQoL) and takes the frequency as well as the severity of problems into account; however, it is not available in German language. The aim of this study was, therefore, to evaluate the reliability and validity of the German version of the OIDP in patients of a private practice.

Material And Methods: Translation of the original OIDP version was performed by a forward-backward process.

Effect of firing time and wall thickness on the biaxial flexural strength of 3D-printed zirconia.

Objectives: To evaluate the effect of accelerated firing on 3D-printed zirconia.

Methods: To check if formulae provided by ISO 6872 can be extended to thin samples, finite element analyses were carried out in advance of fabricating 3-mol% yttria-stabilized tetragonal zirconia polycrystal discs by milling and by 3D-printing. Four groups (n = 38 each) of 3D-printed specimens were produced with two nominal thicknesses (0.

The Effect of Titanium Anodization on the Bond Strength of 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) Resin Cement.

Purpose: To examine the effects of anodization and different surface modifications of titanium on bond strength to 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) resin cement.

Materials And Methods: Grade 5 titanium alloy disks (n = 160) were assigned to one of five prebonding surface treatment study groups (polished; polished and anodized; polished, etched, and anodized; sandblasted; sandblasted and anodized). Disks were adhesively bonded with 10-MDP resin cement (Panavia 21; bonding area: 3.

Fit and Retention of Cobalt-Chromium Removable Partial Denture Frameworks Fabricated with Selective Laser Melting.

Purpose: To evaluate fit and retention of cobalt-chromium removable partial denture (RPD) frameworks fabricated with selective laser melting (SLM).

Methods: Three types of framework for clasp-retained RPDs were virtually designed and fabricated using SLM (n = 30). For comparison, 30 additional frameworks were produced using conventional lost-wax casting.

Immediate loading of dental implants in edentulous mandibles using Locator attachments or Dolder bars: A 9-year prospective randomized clinical study.

Aim: To evaluate the long-term survival, incidence of prosthetic/technical and biological complications and the oral-health-related quality of life in patients with an edentulous mandible who were fitted with overdentures on two immediately loaded implants in the symphyseal area.

Materials And Methods: Forty-six patients with edentulous mandibles received two immediately loaded implant-retained dentures with either two Locator attachments or egg-shaped bar attachments. Implant outcomes were recorded after a period of observation of 9 years and included prosthetic complications, modified gingiva index (mGI), modified plaque index (mPI), oral health impact profile (OHIP-G) and radiographic estimation of bone loss.

The Impact of the SARS-CoV-2 Pandemic on Stress and Anxiety of Dental Students.

Objectives:  To investigate the impact of the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) pandemic on stress and anxiety of preclinical and clinical dental students.

Materials And Methods:  Dental students (participants) in their clinical course (CC;  = 64) or preclinical course (PCC;  = 53) were included in the study. The subjective perceived levels of stress and anxiety were evaluated using the Dental Environment Stress (DES) questionnaire and the Depression, Anxiety and Stress Scales (DASS) questionnaire.

Thermo-flexible resin for the 3D printing of occlusal splints: A randomized pilot trial.

Objectives: To compare the clinical performance of occlusal splints printed from thermo-flexible resin with milled splints.

Methods: A parallel two-arm pilot trial was initiated. Forty-seven patients (n women=38) were recruited from a tertiary care center and randomized using an online tool (sealed envelope).

Influence of geometric dimensions on early failures of adhesively retained composite resin core build-ups.

Objective: To determine the influence of the geometric dimensions of core build-ups on early core build-up failure, that is, loss before definitive prosthesis cementation.

Materials And Methods: Adhesive core build-ups of exclusively vital teeth in 114 participants were evaluated (n materials: 40 Rebilda DC, 38 Multicore Flow, 36 Clearfil DC Core; n teeth: 8 incisors, 54 premolars, 52 molars). Impressions of the abutment teeth were made (1) after removal of insufficient restorations/caries and (2) after core build-up and preparation for a fixed prosthesis.