Influence of Different Nanohybrid Flowable Composite Resin on Shear Bond Strength and Dimensional Changes of Invisalign Attachments After 6 Months of Brushing

Malocclusion Clinical Trial

Official title:

Influence of Different Nanohybrid Flowable Composite Resin on Shear Bond Strength and Dimensional Changes of Invisalign Attachments After 6 Months of Brushing: in Vitro Study and Randomized Clinical Trial

Clinical Trial Details — Status: Enrolling by invitation

Administrative data

• NCT number: NCT06288386
• Other study ID #: 2024-ATTACHMENTS
• Status: Enrolling by invitation
• Phase: N/A
• Start date: March 4, 2024
• Est. completion date: February 2025

Study information

• Verified date: March 2024
• Source: University of Pavia
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The present study will be a single-center, split-mouth, randomized controlled clinical trial. Patients undergoing orthodontic treatment with Invisalign aligners will be enrolled after signing the informed consent. Two different flowable composite resins will be evaluated for the performing of attachments using a split-mouth design:

• group A: Filtek Supreme Flow (3M Unitek, Monrovia, Calif)

• group B: Grandioso Heavy Flow (VOCO GmbH, Cuxhaven Germany)

Digital impressions with iTero intraoral scanner will be performed; digital impressions will be performed after 3 months (T1) and 6 months (T2) from the baseline.

Digital scans will be used to assess any changes in shape and volume of the attachments per each different time frame. Each tooth will be separated from the others and superimpositions of the single tooth will be performed with ZEISS Inspect software.

After attachments placement, the clinicians will be asked to answer, on a scale from 1 to 10, to this questionnaire's questions about the two different flowable composites; each question is repeated for each composite resin.

Type of brushing (with manual or electric toothbrush) and hand of brushing will be recorded.

Description:

The present study will be a single-center, split-mouth, randomized controlled clinical trial. Patients willing to start Invisalign treatment or refinement phases will be recruited from the Unit of Orthodontics and Pediatric Dentistry, Section of Dentistry, Department of Clinical, Surgical, Diagnostic and Pediatric Sciences, University of Pavia, Pavia, Italy. Each patient will sign the informed consent before participation.

The bonding procedure will be the following: isolation of the working field with the placement of a cheek retractor, enamel etching with 37% orthophosphoric acid, rinsing and drying, application of a thin layer of ScotchBond adhesive (3M Unitek, Monrovia, Calif) and light curing. Then, patient will be divided into groups A and B: in group A, attachments will be realized using Filtek Supreme Flow (3M Unitek, Monrovia, Calif) for teeth belonging to mandibular left and maxillary right quadrants, whereas in the remaining quadrants, they will be realized using Grandioso Heavy Flow (VOCO GmbH, Cuxhaven Germany. In group B, quadrants will be inverted. After the bonding of the attachments, digital impressions with iTero intraoral scanner will be performed; digital impressions will be performed after 3 months (T1) and 6 months (T2) from the baseline.

Digital scans will be used to assess any changes in shape and volume of the attachments per each different time frame. Each tooth will be separated from the others and superimpositions of the single tooth will be performed with ZEISS Inspect software.

After attachments placement, the clinicians will be asked to answer, on a scale from 1 to 10, to this questionnaire's questions about the two different flowable composites; each question is repeated for each composite resin.

Type of brushing (with manual or electric toothbrush) and hand of brushing will be recorded.

Sample size calculation was performed assuming Type I error alpha=0.05 and Type II error power = 80% for two independent study groups and a continuous primary endpoint. The primary outcome chosen was "Volumetric change". Based on the results of previous studies [Chen et al., 2021], an expected value of 1.28 was hypothesized. The expected difference between the means was supposed to be 0.44 with a standard deviation of 0.5; therefore, 20 patients were required for the study.

Recruitment information / eligibility

• Status: Enrolling by invitation
• Enrollment: 20
• Est. completion date: February 2025
• Est. primary completion date: February 2025
• Accepts healthy volunteers: No
• Gender: All
• Age group: 14 Years to 70 Years

Eligibility

Inclusion Criteria:

• patients undergoing Invisalign orthodontic treatment

Exclusion Criteria:

• enamel demineralizations

Related Conditions & MeSH terms

• Malocclusion

Intervention

Device:
• GrandioSO Heavy Flow
Attachment will be performed with GrandioSO Heavy Flow.
• Filtek Z350XT Flowable
Attachment will be performed with Filtek Z350XT Flowable.

Locations

Country	Name	City	State
Italy	Unit of Orthodontics and Pediatric Dentistry - Section of Dentistry - Department of Clinical, Surgical, Diagnostic and Pediatrics - University of Pavia	Pavia	Lombardy

Sponsors (1)

Lead Sponsor	Collaborator
University of Pavia

Country where clinical trial is conducted

Italy, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Changes in the volume of attachments	The volumetric changes of attachments will be evaluated through ZEISS Inspect software.	Baseline (T0), after 3 months (T1), after 6 months (T2)
Primary	Attachments failure rate	The failure rate of attachments will be calculated after each month of the study.	Each month until the end of the study (until 6 months)
Primary	Type of brushing	Type of brushing (with manual or electric toothbrush) will be recorded.	Baseline (T0)
Primary	Change in questionnaire's answers	After attachments placement, the clinicians will be asked to answer to this questionnaire's questions about the two different flowable composites; each question is repeated for each composite resin: How manageable did you find the composite resin?; How quick was the placement of composite resin inside the template?; How much excess of composite was present on the surface of tooth around the attachments after their placement?; How easy was the process of finishing and removing composite excess?; How aesthetically acceptable do you find the attachments?; The scale is from 0 to 10, where 0 is the the worse score (negative score), while 10 is the best score (positive score).	Baseline (T0), after 3 months (T1), after 6 months (T2)
Primary	Hand of brushing	Hand of brushing (right or left) will be recorded.	Baseline (T0)