Accuracy of Computer-assisted Template-based Implant Placement Using Conventional or Digital Impression

Study Overview
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Brief Summary
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Proper implant position has a significant impact in esthetic and functional outcomes of implant-supported restorations. Computer-assisted template-based implant placement (guided surgery) have become increasingly popular due to improved planning and the higher transfer accuracy of the virtual plan to the surgical site compared with freehand insertion or freehand final drilling. Digital impressions replace the need for traditional materials that can be inconvenient and messy for patients. To the best of our knowledge, at the time of planning this study, there were no published RCTs evaluating a fully digital approach for computer-assisted template-based implant placement. The aim of the present study is to compare early implant failure, template-related complications, and virtual planning accuracy of computer-assisted template-based implant placement using conventional impression and scan model or digital impression. The null hypothesis is that there will be no difference between these interventions.

Official Title
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Accuracy of Computer-assisted Template-based Implant Placement Using Conventional Impression and Scan Model or Digital Impression: a Randomized Controlled Trial

Conditions
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Dental Implant Failure

Intervention / Treatment
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* Procedure: Conventional impressions
* Procedure: Digital impressions


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: fully or partially edentulous patient, aged 18 years or older, able to sign an informed consent, in need of an implant-supported fixed restoration will be considered eligible for this study. Any potential implant locations based on individual patient requirements will be considered eligible in the present trial. No set location or group of locations will be excluded. Exclusion Criteria: general medical contraindication to oral surgery (American Society of Anesthesiologist, ASA, class III or IV); irradiation in the head and neck area less than one year before implantation; psychiatric problems; alcohol or drug abuse; pregnant or nursing; untreated periodontitis; severe bruxism or clenching; uncontrolled diabetes; poor oral hygiene and motivation; and inability to complete the follow-up.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Conventional impression<br>The intervention of this arm will be conventional impression: polyether impression will be taken with a customized tray. | Procedure: Conventional impressions<br>* In the conventional group, a polyether impression (ImpregumTM, 3M ESPE, Seefeld, Germany) will be taken with a customized tray (Diatray Top, Dental Kontor, Stockelsdorf, Germany). The impression will be poured with Gypsum IV Class Scale 5° (T6, Techim, Techim Group s.r.l., Arese, Italy) and then, the models mounted in a fully adjustable articulator (Protar Evo 7, KaVo Dental, Biberach, Germany). Afterwards, a dental wax-up will be made accordingly to the functional and esthetic requirements. Finally, master model and wax-up will be digitalized by using a lab scanner. A surgical template will be derived from the mounted casts (conventional group) and used to place the implants using guided surgery.<br>|
| Experimental: Digital impression<br>The intervention of this arm will be digital impression: digital impression will be taken using a CS 3600 intraoral scanner . | Procedure: Digital impressions<br>* Patients will be randomly assigned to undergo intraoral digital impression (digital group) or conventional impression (conventional group). In the digital group, a digital impression will be taken using CS 3600 intraoral scanner (Carestream Dental LLC, Atlanta, GA, USA). The digital data (STL, STereo Lithography interface format) will be imported in a 3D design software to realize a virtual wax-up according to the functional and esthetic requirements. A surgical template will be derived from the virtual plane (digital group) and used to place the implants using guided surgery.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Linear distance between planned and real implant apex position | The change in mm between the apex of the planned and the final (real) position of the implant. | Immediate post-surgery | 
| Angle between the planned and real implant axis | Change in angulation between the planned and the final (real) position of the implant. | Immediate post-surgery |