3D Printing Orientation and Film Thickness for Maxillary Complete Dentures

This prospective randomized crossover clinical trial is designed to evaluate and compare 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.

The study will include completely edentulous patients requiring maxillary and mandibular complete dentures. Each participant will receive two maxillary complete dentures fabricated using 3D printing technology with the same printing orientation but two different layer thicknesses (50 μm and 100 μm) in a crossover sequence. Participants will be randomly allocated to one of three printing orientation groups (0°, 45°, or 90°), with five participants in each group.

The three printing orientations being compared are:

• 0° Build Orientation: Maxillary denture bases will be fabricated at a 0° printing orientation using both 50 μm and 100 μm layer thicknesses.
• 45° Build Orientation: Maxillary denture bases will be fabricated at a 45° printing orientation using both 50 μm and 100 μm layer thicknesses.
• 90° Build Orientation: Maxillary denture bases will be fabricated at a 90° printing orientation using both 50 μm and 100 μm layer thicknesses.

Each participant will wear each denture for a three-month evaluation period. The primary outcomes of the study are trueness of the printed denture bases, assessed by comparing the scanned denture base STL files with the original CAD design, and patient satisfaction, evaluated using a Visual Analogue Scale (VAS) for aesthetics, speech, masticatory efficiency, hygiene, and comfort. Dimensional deviation of the denture bases will also be assessed through three-dimensional superimposition analysis at denture insertion and after three months of use.

The findings of this study will help identify the optimal combination of 3D printing orientation and layer thickness for the fabrication of maxillary complete dentures, contributing to improved manufacturing accuracy and enhanced patient satisfaction with digitally fabricated complete dentures.

Primary Outcome Measures

• Trueness of 3D-printed maxillary complete denture bases

Description: To evaluate the trueness of the printed denture bases fabricated using different printing orientations (0°, 45°, and 90°) and layer thicknesses (50 μm and 100 μm).

Method of assessment: The STL file of each printed denture base will be scanned using an extraoral scanner and superimposed with the original CAD design to determine trueness.

Time Frame: At denture fabrication (before clinical insertion).

• Patient Satisfaction

Description: To compare patient satisfaction with dentures fabricated using different 3D printing orientations and layer thicknesses.

Method of assessment: Visual Analogue Scale (VAS; 0-10) evaluating aesthetics, speech, masticatory efficiency, hygiene, and comfort.

Time Frame: 15 days after insertion (baseline) and 3 months after insertion of each denture.

Secondary Outcome Measure

Dimensional Deviation of 3D-printed Maxillary Complete Denture Bases

Description: To evaluate the dimensional stability of the denture bases fabricated with different printing orientations and layer thicknesses.

Method of assessment: Three-dimensional superimposition of scanned STL files to visualize and quantify dimensional deviation.

Time Frame: At denture insertion and after 3 months of clinical use for each denture.

Inclusion criteria

• Completely edentulous patients with good local and systemic health.
• Patients age ranging from 50 to 70 years old.
• Patients with adequate inter-arch space.
• Patients with good neuromuscular control.

Exclusion criteria

• Patients with any oral diseases which may affect denture construction
• Patients with oral parafunctional habits.
• Patients with tempro-mandibular disorders