Ultrasonographic Evaluation of Periodontal Effects of Fixed Retainers

NCT07414264 | Completed DMC

• 1 other identifier: SelcukU-DHF-MO-01
• Study Type: observational
• Target: 53
• Locations: 1 country
• Sites: 1

Brief Summary

This prospective clinical study aims to evaluate the effects of fixed lingual retainers placed after orthodontic treatment on periodontal soft and hard tissue parameters using ultrasonographic imaging. A total of 53 participants (636 anterior teeth) who had completed fixed orthodontic therapy were examined at baseline, 3 months, and 6 months after retainer placement. Ultrasonographic assessments were performed to measure gingival thickness, marginal bone level, and gingival level. Periodontal clinical parameters, including plaque index, gingival index, probing depth, bleeding on probing, and clinical attachment loss, were also recorded. The study seeks to determine whether fixed retainers induce measurable alterations in periodontal structures and to explore potential correlations between gingival phenotype and ultrasonographic findings.

Conditions

Fixed Orthodontic Retainer

Keywords

Fixed Lingual Retainer; Orthodontic Retention; Ultrasonography; Gingival Thickness

Outcome Measures

Primary Outcomes (1)

• Change in Gingival Thickness Measured by Ultrasonography

  Gingival thickness will be measured at baseline (T0), 3 months (T1), and 6 months (T2) after placement of fixed lingual retainers using high-frequency intraoral ultrasonography. Measurements will be performed at the mid-facial aspect of anterior teeth, perpendicular to the long axis of the tooth, through a customized silicone probe cap to ensure consistent contact and accuracy. The primary outcome is the mean change in gingival thickness (in millimeters) between baseline and 6-month evaluations, reflecting potential soft tissue alterations associated with fixed lingual retainers.

  6 months

Study Arms (4)

1. Maxillary Retroclination Group

Participants with completed fixed orthodontic treatment presenting retroclined maxillary anterior teeth. This group represents patients whose upper incisors show a lingual inclination relative to the Sella-Nasion (SN) plane. Periodontal and ultrasound (USG) parameters are evaluated at baseline, 3 months, and 6 months following retention.

2. Maxillary Proclination Group

Participants with completed fixed orthodontic treatment showing proclined maxillary anterior teeth. The upper incisors present a labial inclination relative to the SN plane. Periodontal and ultrasound (USG) parameters are compared across time intervals during retention.

3. Mandibular Retroclination Group

Participants with completed fixed orthodontic treatment and retroclined mandibular anterior teeth. The lower incisors exhibit lingual inclination relative to the mandibular plane. Periodontal and ultrasound (USG) parameters are longitudinally monitored during retention.

Mandibular Proclination Group

Participants with completed fixed orthodontic treatment presenting proclined mandibular anterior teeth. The lower incisors display labial inclination relative to the mandibular plane. Periodontal and ultrasound (USG) measurements are performed at baseline, 3-month, and 6-month follow-ups.

Eligibility Criteria

• Age: 16 Years - 24 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

The study population consisted of individuals who had completed fixed orthodontic treatment at the Department of Orthodontics, Selçuk University Faculty of Dentistry. All participants were systemically healthy, non-smoking young adults aged between 16 and 24 years, with good oral hygiene and no active periodontal disease. Each subject had maxillary and/or mandibular anterior teeth bonded with fixed retainers in passive condition. A total of 53 individuals (636 anterior teeth) were evaluated and categorized into four subgroups according to the inclination of anterior teeth: maxillary retroclination, maxillary proclination, mandibular retroclination, and mandibular proclination.

You may qualify if:

• Patients who have completed comprehensive orthodontic treatment with fixed appliances.
• Patients with a fixed mandibular or maxillary lingual retainer in place for at least 6 months.
• Age between 18 and 40 years.
• Good general health with no systemic conditions affecting periodontal tissues.
• Non-smokers or light smokers (\<5 cigarettes/day).
• Presence of all anterior teeth without significant restorations or prosthetic crowns.

You may not qualify if:

• History of periodontal surgery or advanced periodontitis prior to orthodontic treatment.
• Systemic diseases or medications affecting periodontal health (e.g., diabetes, immunosuppressive therapy).
• Pregnancy or lactation.
• Poor oral hygiene or non-compliance with oral hygiene instructions.
• Teeth with caries, large restorations, or endodontic treatment in the area of interest.
• Patients with removable retainers or interrupted use of fixed retainers.

Sponsors & Collaborators

• Selcuk University: lead

Study Sites (1)

Selcuk University Faculty of Dentistry

Konya, Selçuklu, 42060, Turkey (Türkiye)

Location

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Research Assistant

Study Record Dates

• First Submitted: February 9, 2026
• First Posted: February 17, 2026
• Study Start: October 24, 2024
• Primary Completion: August 4, 2025
• Study Completion: October 9, 2025
• Last Updated: February 17, 2026

Record last verified: 2026-02

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)