Clinical Research Directory

Subcrestal vs Juxtacrestal PRAMA Implants With Variable Necks

The goal of this clinical trial is to understand how different implant neck designs and placement depths affect the surrounding bone and peri-implant tissue (the tissue around a dental implant) in adults who need implants in the back areas of the mouth (molars and premolars). The main questions it aims to answer are: Does placing implants deeper under the bone crest (subcrestally) help preserve more bone and peri-implant tissue over time? Do implants with longer, conical necks and micro-threaded surfaces result in more stable peri-implant tissue than implants with shorter necks? Researchers will compare three types of one-piece dental implants with different neck heights (short, standard, and long), placed at different depths in the jawbone, to determine which combination better maintains bone and peri-implant tissue levels. Participants will: Receive two dental implants in the posterior upper or lower jaw Be randomly assigned to one of three groups depending on implant neck design and placement depth Undergo implant surgery using a digital workflow, with healing over three months Be rehabilitated with custom zirconia bridges Return for regular clinical and imaging checkups over a period of at least 3 years This study aims to generate evidence that helps clinicians choose implant designs and techniques that promote long-term peri-implant tissue health.

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.