Clinical Evaluation of Three-Dimensional (3D) Printing Resin Nanoceramic Crown Restoration.

Clinical Evaluation of Resin Nanoceramic Crown Restoration for Posterior Teeth Fabricated by Three-Dimensional (3D) Printing: Short-Term Clinical Study

This study aims to evaluate the function and aesthetics of ceramic-filled hybrid resin permanent crowns produced by 3D printing method in posterior teeth according to Revised FDI criteria.

At the Department of Prosthodontics, Faculty of Dentistry, Ege University, 60 patients who present for single-tooth crown restoration in the posterior region of either the maxilla or mandible and who meet the inclusion criteria will receive a total of 60 permanent crown restorations. Following tooth preparation, the restorations will be fabricated using a three-dimensional (3D) printing technique with a ceramic-filled hybrid resin material (VarseoSmile TriniQ, Bego, Bremen, Germany).

The effects of restorations on clinical success will be evaluated according to demographic data (age, gender, etc.) and modified USPHS and Revised FDI criteria, and statistical analysis will be applied to the recorded data. Follow-up visits are scheduled at 0: baseline, 6, and 12 months.

The study will be conducted between June 2025 and June 2026. Tooth preparation will be performed following clinical and radiographic examinations. The study schedule will be explained in detail to all patients included in the study.

According to the power analysis performed (G*Power Ver. 3.0.10), at a significance level of p= 0.05, the inclusion of at least 16 patients was determined to be necessary to achieve a statistical power of at least 80%. To further increase the power of the study, it was planned to include 60 patients who meet the inclusion criteria.

Eligible patients will be provided with detailed and comprehensible information regarding the content of the study. Subsequently, the informed consent form will be presented and read, and any questions from the patient will be addressed. If the patient agrees to participate in the study, the form will be signed.

Prosthetic treatment phase:

In the clinics of the Department of Prosthodontics, Faculty of Dentistry, Ege University, following completion of tooth preparation, crown restorations will be fabricated from a ceramic-filled permanent hybrid resin material (VarseoSmile TriniQ, Bego, Bremen, Germany) using a 3D printing technique, based on intraoral optical scans obtained with an intraoral scanner (iTero 5D Element Plus, Align Technology, USA). The restorations will be cemented with a self-adhesive resin cement Panavia V5 Standard Kit (Kuraray Noritake, Osaka, Japan). Occlusion will be checked, and patients will be provided with routine oral hygiene instructions.

Clinical and radiographic evaluations of 3D-printed crowns will be performed at 6 and 12 months. Data will be recorded according to the revised FDI criteria and modified united states public health service USPHS criteria.

At each follow-up visit, patients' teeth will be scanned using intraoral scanner (iTero 5D Element Plus, Align Technology, USA). The STL files of scans will be superimposed using Geomagic software, and the wear will be evaluated.

Inclusion Criteria:

• Individuals between 18 and 65 years of age, Patients requiring a single crown restoration in the posterior region of the maxilla or mandible, Absence of active periodontal disease, Presence of an opposing tooth (natural or restored), Presence of adjacent teeth (mesial and distal), Vital or endodontically treated (devital) teeth without periapical lesions, Patients who agree to comply with the study conditions will be included in the study.

Exclusion Criteria:

• Suspected or confirmed pregnancy, or patients in the breastfeeding period, Teeth requiring coverage that are intended to serve as abutments for fixed partial dentures, Vital or endodontically treated (devital) teeth with periapical lesions, Absence of an opposing tooth or presence of an opposing tooth restored with a crown, Absence of adjacent teeth (mesial or distal), Individuals with temporomandibular joint disorders (TMDs), patients who do not consent to the study conditions will be excluded from the study.