Clinical Research Directory

Accuracy of Standard and Geometric Pattern-Assisted Digital Scanning for Full-Arch Implant Prosthesis Frameworks

This clinical trial aims to compare three different impression techniques used to fabricate full-arch implant-supported dental prostheses. Accurate impressions are essential to ensure a passive and precise fit of the final prosthetic framework, which contributes to long-term implant success and patient comfort. In this crossover study, participants with four osseointegrated dental implants in the lower jaw will undergo three types of impressions: Conventional splinted impression using polyvinyl siloxane (PVS) material. Standard digital impression using an intraoral scanner. Geometric pattern-assisted digital impression, which incorporates a visual reference pattern to improve scan alignment and accuracy. Each participant will receive all three impression techniques in a randomized sequence, at different time points. The accuracy of each method will be assessed by evaluating the passivity of the resulting prosthetic frameworks using two methods: (1) digital superimposition analysis to measure three-dimensional (3D) spatial deviation, and (2) the clinical "one-screw test" to detect misfit. The study seeks to determine whether digital scanning, particularly with geometric pattern assistance, can provide accuracy comparable to or better than conventional methods. Findings may guide improvements in digital prosthodontic workflows and support more efficient, predictable treatment outcomes.

Evaluation of Ceramic Dental Crown Clinical Performance After Conventional Hydrofluoric Acid Etching or Gaseous Plasma Pretreatment

In this randomized, controlled, double-blind clinical trial, we will follow adult participants who receive partial or full dental crowns made of lithium disilicate ceramic (LDC). Before the crowns are permanently attached to teeth, those in the control group will be etched with hydrofluoric acid (HF) according to the standard laboratory protocol, while those in the intervention group will undergo an innovative surface treatment with atmospheric-pressure nonthermal plasma (APP). The goal of this study is to determine whether the innovative APP pretreatment of LDC crowns can result in outcomes comparable to or better than those achieved with the standard HF treatment, including: * oral health-related quality of life as reported by the participants; and * the clinical success and survival of LDC crowns. Participants will be asked to attend scheduled follow-up visits 1 week and 1, 3, 6, and 12 months after the crowns are cemented. At each visit: * a researcher will examine the crowns and surrounding teeth and tissues for any biological or technical complications; and * participants will complete a questionnaire to assess their oral health-related quality of life.

3D Printing Orientation and Film Thickness for Maxillary Complete Dentures

This randomized crossover clinical trial aims to evaluate the effect of different three-dimensional (3D) printing orientations and layer thicknesses on the trueness, dimensional accuracy, and patient satisfaction of maxillary complete dentures in completely edentulous patients. Each participant will receive two maxillary 3D-printed complete dentures fabricated using the same printing orientation (0°, 45°, or 90°) with two different layer thicknesses (50 μm and 100 μm) in a crossover sequence. The study will compare the influence of these printing parameters on denture accuracy and patient-reported outcomes to identify the optimal 3D printing settings for complete denture fabrication.

Masticatory Efficiency, Bite Force, and Patient-Reported Outcomes in Patients Rehabilitated With Complete and Partial Dentures Supported by Teeth, Mini-Implants, or Conventional Implants

This study aims to evaluate masticatory efficiency, bite force, and patient-reported outcomes in edentulous and partially edentulous patients rehabilitated with different removable prosthodontic treatment modalities. The study includes both cross-sectional and longitudinal components. The cross-sectional component will compare patients wearing conventional complete dentures, conventional removable partial dentures, mini-implant-retained overdentures, conventional implant-retained overdentures, and implant-assisted removable partial dentures. The longitudinal component will assess changes in masticatory performance, bite force, and patient-reported outcomes following prosthodontic rehabilitation and adaptation over time. The study seeks to determine whether implant-assisted treatment options provide superior functional outcomes, oral health-related quality of life, and patient satisfaction compared with conventional removable prostheses.

Effect of PEEK and Titanium Framework Reinforcement on Marginal Bone Loss Around Implants Supporting a Fixed All-on-four Prosthesis in Completely Edentulous Mandibles

A fixed all-on-four prosthesis will be constructed for the lower arch for each patient and the marginal bone loss will be evaluated at baseline, 3,6,9 and 12 months.