Effects of the Continuous Wear of Invisalign® Trays on the Temporomandibular Joints and Orofacial Muscular Complex

The aim of the study is to evaluate the effects of orthodontic treatment using Invisalign® on the temporomandibular joint (TMJ) and orofacial muscular complex, on the recorded number of bruxism/clenching events during sleep, and on the reported amount of bruxism/clenching events during the day.

Principal objective:

• Evaluation of the effect of continuous wear of Invisalign® trays on the TMJ and muscles of the orofacial complex.

Secondary objectives:

• Objective evaluation of the effect of Invisalign® trays on bruxism/clenching events at night.
• Subjective evaluation of the effect of Invisalign® trays on bruxism/clenching during the day.
• Evaluation of the evolution of symptoms over the course of six months.

Appointment 1:

-Initial Exam (Initial complete orthodontic record)

Appointment 2 (T0):

• Presentation of the treatment plan
• Informed consent
• iTero Scan for Invisalign
• TMJ exam (baseline)
• Diagnostic bruxism/clenching questionnaire (baseline)
• Give Electromyogram (EMG) machine to patient for night study at home (baseline)
• Instructions on how to use the EMG machine
• NB: Patient returns EMG by courier

Appointment 3:

• Delivery of Invisalign® trays #1
• Instructions on wearing the Invisalign® trays
• Take mailing information to send EMG machine by courier (EMG recording the night before Appointment 4 / T1)

Appointment 4 (T1: 2 weeks after appointment 3):

• Patient brings back EMG machine
• TMJ exam
• Daytime bruxism/clenching questionnaire
• Bonding attachments onto teeth
• Give Invisalign® trays #2
• NB: Patient will be followed every 6-8 weeks

Appointment 5 (T2: 6 months after appointment 4):

• TMJ exam
• Daytime bruxism/clenching
• Give EMG machine for night study at home
• Patient returns EMG by courier

All subjects in the study will be treated using the Invisalign® appliance. To obtain statistically and clinically significant results, it was calculated that at least 30 patients will need to complete the study. Our objective is to recruit about 40 patients.

Inclusion criteria

• Permanent dentition
• No congenially permanent teeth missing (with the exception of 3rd molars)
• Patient requiring a non-extraction orthodontic treatment
• Patient followed by the University of Montreal port-graduate orthodontic clinic
• Cl.I skeletal relation (or mild cl.II / mild cl.III)
• Patient can speak and read french
• In good health
• Patient and parents accept and sign informed consent form.
• Periodontal health permits orthodontic treatment
• Adequate oral hygiene

Exclusion criteria

• Diagnosed TMJ's dysfunction
• Severe TMJ's dysfunction
• Lack of attendance