Digital Intraoral Scanning With and Without Prefabricated Landmarks Versus Conventional Impression Technique

Official title

Accuracy of Digital Intraoral Scanning With and Without Prefabricated Landmarks Versus Conventional Impression Technique for Mandibular Implant Supported Full-Arch Prosthesis

Overview

The aim of this clinical trial is to evaluate the accuracy of digital implant impressions with or without prefabricated landmarks between scan bodies compared to conventional impression technique in mandibular full-arch implant cases.

Detailed description

Implant-supported full arch dental prostheses are crucial and reliable alternatives for individuals with missing teeth in their jaws. The initial phase in the production of implant-supported prostheses involves the impression-taking process. Inaccurate impressions can result in a misfit between the prosthesis and implant abutment, potentially causing both mechanical and biological complications that can adversely affect the long-term viability of the implants. Therefore, the precision of impressions is of utmost importance, particularly for prostheses supported by multiple implants.

The conventional approach to obtaining impressions for multiple implants involves the use of an open-tray technique, widely adopted in dental practice. In this method, impression copings are connected to prevent rotational movements, making it a preferable choice compared to the non-splinting technique. Nevertheless, this procedure is complex, less efficient, and demands considerable clinical expertise. It is advised for use by experienced dentists, as those lacking experience have shown a notably higher rate of unsuccessful outcomes when employing the splinting technique.6 Additionally, various factors, such as patients' pharyngeal reflex and the potential deformation of impression materials, can influence the accuracy of implant impressions in the conventional workflow.

With the advancement of computer-aided design/computer-aided manufacturing (CAD/CAM) and digital technologies, the intraoral scanner (IOS) has gained popularity for capturing implant positions. In clinical practice, IOSs are valued for their comfort, efficiency, and practicality. However, it's important to note that IOSs cannot completely replace traditional methods. When it comes to implant-supported fixed dental prostheses, intraoral scanners can effectively be used for single- and three-unit implant scanning.

In a study from 2020, Revell et al. recommended specific scanners, such as Primescan, for complete-arch implant impressions due to their low deviation values at the implant platform level. Nevertheless, the accuracy of older models of intraoral scanners may not be reliable when scanning edentulous spaces with long inter-implant distances or fully edentulous jaws, particularly in the hands of inexperienced operators.

Previous research has introduced custom-designed scan bodies featuring an extensional structure to achieve dependable digital full-arch implant impressions. Typically, these platforms necessitate the use of custom-made scan bodies or a secondary scan to obtain mucosal information. In this context, this study is conducted to present newly designed prefabricated landmarks between the scan bodies to offer a solution for digital scanning of a mandibular full-arch implant. Therefore, the aim of this study is to evaluate and compare the accuracy of digital intraoral scanning with or without prefabricated landmarks to conventional impression techniques in mandibular full-arch implant cases.

The null hypothesis posits that there would be no significant difference in accuracy between digital intraoral scanning with or without prefabricated landmarks between scan bodies and conventional impression techniques.

Interventions

• Device Digital Impression by using Intraoral Scanning of Scan Bodies
  intraoral scanning will be used to capture the positions of full-arch mandibular implants with the aid of scan bodies.
• Device Digital Impression by using Intraoral Scanning of Scan Bodies with Prefabricated Landmarks
  intraoral scanning will be used to capture the positions of full-arch mandibular implants with the aid of scan bodies with prefabricated landmarks in place.
• Device Splinted Open Top Tay Conventional Impression Technique
  Splinted open-top tray conventional impression technique will be preformed by using medium body silicone impression material.

Primary outcome measures

• The accuracy of digital intraoral scanning of full-arch mandibular implants. [Time frame: Baseline]

Eligibility criteria

Inclusion criteria

• patients with completely edentulous mandible, non-smokers, 50-70 years in age, have Good oral hygiene and motivation.

Exclusion criteria

• patients with major systemic diseases that may affect osseointegration as uncontrolled diabetes mellitus, the need for extensive bone grafting in planned implant site, pregnancy, patients under bisphosphonate treatment, and limited mouth-opening for executing the guided implant surgery.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Non-randomized

Model

Crossover

Masking

Double blind

Primary purpose

Other

Study locations

Center list to be confirmed — check the primary protocol.

Publications

• Papaspyridakos P, Mokti M, Chen CJ, Benic GI, Gallucci GO, Chronopoulos V. Implant and prosthodontic survival rates with implant fixed complete dental prostheses in the edentulous mandible after at least 5 years: a systematic review. Clin Implant Dent Relat Res. 2014 Oct;16(5):705-17. doi: 10.1111/cid.12036. Epub 2013 Jan 11. PMID 23311617
• Goodacre CJ, Bernal G, Rungcharassaeng K, Kan JY. Clinical complications with implants and implant prostheses. J Prosthet Dent. 2003 Aug;90(2):121-32. doi: 10.1016/S0022-3913(03)00212-9. PMID 12886205
• Pjetursson BE, Thoma D, Jung R, Zwahlen M, Zembic A. A systematic review of the survival and complication rates of implant-supported fixed dental prostheses (FDPs) after a mean observation period of at least 5 years. Clin Oral Implants Res. 2012 Oct;23 Suppl 6:22-38. doi: 10.1111/j.1600-0501.2012.02546.x. PMID 23062125
• Papaspyridakos P, Chen CJ, Gallucci GO, Doukoudakis A, Weber HP, Chronopoulos V. Accuracy of implant impressions for partially and completely edentulous patients: a systematic review. Int J Oral Maxillofac Implants. 2014 Jul-Aug;29(4):836-45. doi: 10.11607/jomi.3625. PMID 25032763
• Papaspyridakos P, Gallucci GO, Chen CJ, Hanssen S, Naert I, Vandenberghe B. Digital versus conventional implant impressions for edentulous patients: accuracy outcomes. Clin Oral Implants Res. 2016 Apr;27(4):465-72. doi: 10.1111/clr.12567. Epub 2015 Feb 13. PMID 25682892
• Perez-Davidi M, Levit M, Walter O, Eilat Y, Rosenfeld P. Clinical accuracy outcomes of splinted and nonsplinted implant impression methods in dental residency settings. Quintessence Int. 2016;47(10):843-852. doi: 10.3290/j.qi.a36323. PMID 27284582
• Miyoshi K, Tanaka S, Yokoyama S, Sanda M, Baba K. Effects of different types of intraoral scanners and scanning ranges on the precision of digital implant impressions in edentulous maxilla: An in vitro study. Clin Oral Implants Res. 2020 Jan;31(1):74-83. doi: 10.1111/clr.13548. Epub 2019 Oct 28. PMID 31608509
• Nagata K, Fuchigami K, Okuhama Y, Wakamori K, Tsuruoka H, Nakashizu T, Hoshi N, Atsumi M, Kimoto K, Kawana H. Comparison of digital and silicone impressions for single-tooth implants and two- and three-unit implants for a free-end edentulous saddle. BMC Oral Health. 2021 Sep 23;21(1):464. doi: 10.1186/s12903-021-01836-1. PMID 34556111

Identifiers

NCT: NCT06592066 · FDASU-Rec ID022403

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗