Effectiveness of Dental Bleaching Using Different Designs of 3D-Printed and Conventional Customized Nightguards

Official title

Evaluation of the Effectiveness in Dental Bleaching by Different Designs of 3D-Printed Digital Customized Nightguards

Overview

This randomized, double-blind, split-mouth clinical trial evaluates the effectiveness of at-home dental bleaching using customized nightguards fabricated by digital (3D-printed CAD-CAM) and conventional methods, with and without reservoirs. Adult participants with good general and oral health and a baseline tooth shade of A2 or darker undergo bleaching with 10% carbamide peroxide. Outcomes include tooth color change (subjective and spectrophotometric measures), tooth sensitivity, gingival irritation, patient comfort, and patient satisfaction over time.

Detailed description

This study compares the effectiveness of at-home dental bleaching using customized conventional vacuum-formed trays and digitally fabricated (3D-printed CAD-CAM) trays. It also compares tray designs with and without reservoirs using a randomized split-mouth design.

Each participant receives both tray fabrication approaches and both reservoir conditions, distributed according to randomized allocation. Bleaching is performed with 10% carbamide peroxide. Participants are followed during and after treatment to assess tooth color change, tooth sensitivity, gingival irritation, comfort, and satisfaction.

Tooth color is assessed using both visual and spectrophotometric methods. A customized positioner is used to standardize the measurement location throughout the study.

Interventions

• Procedure Customized bleaching tray fabrication
  Customized bleaching trays were fabricated using either a conventional vacuum-forming technique or a digital CAD-CAM 3D-printing technique, according to randomized allocation within a split-mouth design.
• Procedure Reservoir tray design
  Tray designs were prepared either with a reservoir or without a reservoir, according to randomized allocation across hemiarches within the split-mouth design.
• Drug Carbamide peroxide 10%
  At-home bleaching gel containing 10% carbamide peroxide applied in customized trays according to the study protocol

Primary outcome measures

• Tooth color change (spectrophotometer; ΔE*ab) [Time frame: T0 (baseline, Day 0); T1 (Week 1); T2 (Week 2); T3 (Week 3); T4 (Week 4); T5 (Week 6, end of bleaching); T6 (Week 8, 2 weeks post-bleaching).]
• Tooth shade change (VITA Bleachedguide 3D-MASTER; shade guide units) [Time frame: T0 (baseline, Day 0); T1 (Week 1); T2 (Week 2); T3 (Week 3); T4 (Week 4); T5 (Week 6, end of bleaching); T6 (Week 8, 2 weeks post-bleaching).]

Secondary outcome measures (6)

• Tooth sensitivity (Numeric Rating Scale, 0-4) [Time frame: T0 (baseline, Day 0); T1 (Week 1); T2 (Week 2); T3 (Week 3); T4 (Week 4); T5 (Week 6, end of bleaching); T6 (Week 8, 2 weeks post-bleaching).]
• Tooth sensitivity (Visual Analog Scale, 0-10) [Time frame: T0 (baseline, Day 0); T1 (Week 1); T2 (Week 2); T3 (Week 3); T4 (Week 4); T5 (Week 6, end of bleaching); T6 (Week 8, 2 weeks post-bleaching).]
• Gingival irritation presence (NRS, 0-2) [Time frame: T0 (baseline, Day 0); T1 (Week 1); T2 (Week 2); T3 (Week 3); T4 (Week 4); T5 (Week 6, end of bleaching); T6 (Week 8, 2 weeks post-bleaching).]
• Gingival irritation severity (NRS, 0-2) [Time frame: T0 (baseline, Day 0); T1 (Week 1); T2 (Week 2); T3 (Week 3); T4 (Week 4); T5 (Week 6, end of bleaching); T6 (Week 8, 2 weeks post-bleaching).]
• Patient comfort (VAS, 0-10) [Time frame: T0 (baseline, Day 0); T1 (Week 1); T2 (Week 2); T3 (Week 3); T4 (Week 4); T5 (Week 6, end of bleaching); T6 (Week 8, 2 weeks post-bleaching).]
• Patient satisfaction with tooth color change (VAS, 0-10) [Time frame: T0 (baseline, Day 0); T1 (Week 1); T2 (Week 2); T3 (Week 3); T4 (Week 4); T5 (Week 6, end of bleaching); T6 (Week 8, 2 weeks post-bleaching).]

Eligibility criteria

Inclusion criteria

• Adults aged 18 years or older
• Good general and oral health
• No current medical treatment (self-reported)
• No need for surgical, endodontic, periodontal, or restorative dental treatment
• At least six upper and six lower anterior teeth free of caries and restorations
• Maxillary central incisors with baseline shade A2 or darker
• Willingness to follow the study protocol and use the study-provided oral hygiene products/instructions

Exclusion criteria

• Previous tooth bleaching treatment
• Orthodontic appliances or prostheses that interfere with treatment
• Severe intrinsic discoloration (e.g., tetracycline staining, fluorosis, or endodontically treated teeth with discoloration)
• Pregnancy or lactation
• Bruxism
• Gingival recession, dentin exposure, visible enamel cracks, or other conditions associated with increased sensitivity
• Use of anti-inflammatory or analgesic medication during the study period (according to protocol)

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

Healthy volunteers: Yes

Study design

Allocation

Randomized

Model

Factorial

Masking

Double blind

Primary purpose

Treatment

Study locations

Spain · 1 center

• Clínica Universitària d'Odontologia UIC Barcelona — Sant Cugat del Vallès

Identifiers

NCT: NCT07464197 · REST-ECL-2021-06

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗