Comparative Evaluation Of Accuracy in Terms of Trueness, Precision and Angle deviation of Multiple Implant Impressions in Digital and Splinted Closed Tray With Splinted Open Tray Impression Method: A Randomised Controlled Clinical Trial

The objective of contemporary dentistry is to return patients to a state of normal contour, function, comfort, aesthetics, speech, and health, whether it involves restoring a single tooth or replacing multiple teeth. As the number of missing teeth increases in a patient, achieving this goal becomes increasingly challenging. Osseointegrated Dental implants have provided better treatment option for individuals who have lost their teeth, serving as an alternative to traditional prostheses. The positioning of implants is dictated by the anatomy of the remaining ridges. These implants have demonstrated promising long-term outcomes for patients. Creating impressions is a fundamental aspect of prosthesis fabrication. The choice of impression material and technique significantly impacts the fit of the prosthesis. Accurately transferring the spatial relationships of implants from the oral cavity to the master cast through the impression process is the initial and vital step to ensure a passive fit of the implant framework. Various impression techniques are recommended to create a master cast ensuring the passive fit of implant-supported prostheses. Two conventional methods include the open tray method (Direct method /pick-up impression technique) and the closed tray method (Indirect method /transfer impression technique). Conventional implant impression using elastomeric impression material have been a standard procedure for fixed prosthodontics for a long time however, digital implant impressions using intraoral scanners (IOS) are a comparatively recent but steadily advancing technique. The utilization of intraoral scanners is on the rise, particularly for implant-supported fixed dental prostheses. Intraoral scan bodies essentially function to transfer the intraoral implant position to the digital model.

Primary Objectives:-

1. To evaluate the accuracy of multiple implant impression in terms of trueness, precision and angle deviation using digital method.
2. To evaluate the accuracy of multiple implant impression in terms of trueness, precision and angle deviation using splinted closed tray impression.
3. To evaluate the accuracy of multiple implant impression in terms of trueness, precision and angle deviation using splinted open tray impression method. Method of measurement:  The 36 candidates will be selected according to the inclusion and exclusion criteria. Digital impression, splinted closed tray, splinted open tray impression and will be made. Intraoral scanning will be done according to the manufacturer’s instructions. Implant Impression of patients with partial edentulous arch with two or more implants placed unilaterally will be made. Digital impression method: The scan bodies will be affixed to the implants. Intraoral scanning will be performed according to the manufacturer’s instructions.  Subsequently, a Standard Tessellation Language (STL) file will be generated from the scan data. Finally, a model will be fabricated based on the digital scan using 3D printer. splinted open tray and closed tray impression coping will be used for respective impression techniques and it will be splinted using dental floss and BIS-GMA resin. The inter-implant distance between two or more implant will be measured using coordinate measuring machine in x, y and z axis of all the obtained casts. Obtained data will be uploaded to the Software and accuracy will be evaluated and compared. The series of operations will be performed on all combinations of the type IV gypsum casts for open and closed tray impressions and digital model sets for each patient. Obtained data will be evaluated and compared amongst the group based on trueness, precision and angle deviation of every impression technique.