Orthodontic and Articular Effects of the One-Step No-Prep Protocol

Official title

Investigation of the Orthodontic and Articular Effects of the One-Step No-Prep Protocol

Overview

This study investigates how the One-Step No-Prep protocol with orthodontic assistance affects dental and jaw function in adults treated for localized tooth wear. It focuses on the predictability and extent of orthodontic tooth movements, the impact on temporomandibular joint position and function, and the quality and long-term stability of the restored bite. Participants will receive minimally invasive bonded restorations combined with simple orthodontic mechanics. The study will evaluate changes in tooth position, bite contacts, facial vertical height, and temporomandibular joint function using digital scans, low-dose 3D imaging, jaw-tracking, and clinical examinations. Patient comfort, function, and satisfaction will also be assessed through questionnaires. The goal is to better understand how this conservative treatment performs over time.

Detailed description

This study evaluates the clinical, orthodontic, and functional outcomes of the One-Step No-Prep protocol with orthodontic assistance (OSNPO) in adult patients presenting with localized tooth wear. The OSNPO approach combines bonded restorations placed without tooth preparation and controlled orthodontic extrusion to re-establish posterior occlusion. Although the protocol has shown promising clinical results, several key aspects have not yet been quantified or documented systematically.

The study includes both prospective and retrospective participants treated at the University Hospital of Liège. Prospective cases undergo standardized digital assessments, including intraoral scanning, low-dose cone-beam CT, and 3D jaw-tracking, while retrospective cases contribute long-term clinical and occlusal data. Follow-up extends to 5 years, with an additional evaluation at 10 years.

The primary focus is to characterize the nature and magnitude of orthodontic tooth movements, the time required to regain full occlusion, and the short- and long-term stability of occlusal contacts after treatment. Additional analyses examine changes in vertical facial dimensions, as well as temporomandibular joint position and function before and after treatment. Secondary outcomes include the clinical performance of PICN restorations and patient-reported measures of comfort, function, esthetics, and quality of life.

By integrating digital imaging, functional analysis, and patient-centered outcomes, this study aims to clarify the biological mechanisms underlying OSNPO, identify predictors of treatment duration and stability, and support evidence-based use of this minimally invasive protocol in the management of tooth wear.

Interventions

• Radiation Low-dose Cone-Beam Computed Tomography
  Acquisition of a low-dose, large-field CBCT scan performed specifically for research purposes after completion of the OSNPO treatment, used to assess tooth movements, vertical facial dimensions, and temporomandibular joint position.

Primary outcome measures

• Three-dimensional orthodontic tooth movements (linear) [Time frame: Baseline and end of OSNPO treatment (approximately 1 month)]
• Three-dimensional orthodontic tooth movements (angular) [Time frame: Baseline and end of OSNPO treatment (approximately 1 month)]
• Time required to re-establish functional occlusion [Time frame: Baseline and end of OSNPO treatment (approximately 1 month)]
• Occlusal contacts [Time frame: Baseline; 1 month; annually up to 5 years; and at 10 years.]
• Occlusal contacts stability [Time frame: Baseline; 1 month; annually up to 5 years; and at 10 years.]
• Changes in vertical facial height [Time frame: Baseline and end of OSNPO treatment (approximately 1 month)]
• Temporomandibular joint position [Time frame: Baseline and end of OSNPO treatment (approximately 1 month)]
• Temporomandibular joint function [Time frame: Baseline and end of OSNPO treatment (approximately 1 month)]

Secondary outcome measures (5)

• Clinical performance of PICN partial restorations [Time frame: 1 month; annually up to 5 years; 10 years.]
• Longevity of PICN partial restorations [Time frame: 1 month; annually up to 5 years; 10 years.]
• Oral health-related quality of life (OHIP-49) [Time frame: Baseline; weekly during orthodontic treatment; 1 month; annually up to 5 years; 10 years.]
• Musculoskeletal symptoms [Time frame: Baseline; 1 month; annually up to 5 years; 10 years.]
• Patient satisfaction [Time frame: 1 month]

Eligibility criteria

Inclusion criteria

• Localized tooth wear that will be treated, or has already been treated, using the OSNPO protocol.
• Age 18 years or older.
• Sufficient cognitive ability to understand the study procedures and complete the required assessments.
• Ability to read and complete the study questionnaires in French.
• Written informed consent provided.

Exclusion criteria

• No exclusion criteria.

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

Healthy volunteers: No

Study design

Allocation

N/A

Model

Single group

Masking

Open label

Primary purpose

Basic science

Study locations

Belgium · 1 center

• University Hospital of Liège — Liège

Publications

• Hickel R, Peschke A, Tyas M, Mjor I, Bayne S, Peters M, Hiller KA, Randall R, Vanherle G, Heintze SD. FDI World Dental Federation - clinical criteria for the evaluation of direct and indirect restorations. Update and clinical examples. J Adhes Dent. 2010 Aug;12(4):259-72. doi: 10.3290/j.jad.a19262. PMID 20847997

Identifiers

NCT: NCT07533240 · B7072025000111

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗