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Orthognathic Speech Pathology: Phonetic Contrasts of Patients With Dental Discrepancies Pre- and Post-Treatment Analyses (OSP)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details. Identifier: NCT04117360
Recruitment Status : Recruiting
First Posted : October 7, 2019
Last Update Posted : February 5, 2020
North Carolina State University
Information provided by (Responsible Party):
University of North Carolina, Chapel Hill

Brief Summary:
The investigators are studying how speech is effected by jaw and tooth position in jaw surgery patients. Eighty percent of our jaw surgery patients have speech pathologies, compared to five percent of the general population, but speech pathologists do not understand why. The investigators hypothesize that open bites and underbites prevent most patients from being able to pronounce words normally and surgical correction will lead to improvement in speech. Patients will be audio recorded speaking and patients' tongue gestures ultrasound recorded before and after their jaw surgeries to observe what changes occur in their speech and tongue movements.

Condition or disease Intervention/treatment
Dentofacial Abnormalities Dentofacial Deformities Dentofacial Anomalies, Including Malocclusion Malocclusion Malocclusion in Children Dentofacial Disharmony Skeletal Malocclusion Skeletal Malformation Speech Sound Disorder Speech Disorders Other: Orthognathic surgery and Orthodontics

Detailed Description:

Purpose: The investigators are studying how phoneme distortion is effected by jaw disproportions in dentofacial disharmony (DFD) patients and whether speech improves after orthognathic surgery and orthodontic treatment. Spectral moment and tongue gestural analysis are being used to mechanistically determine how jaw position effects speech. The investigators hypothesize that skeletal open and underbites contribute to phoneme distortion and tongue gestural changes that improve following surgical correction of jaw position. All DFD patients are already seeking treatment from orthodontics and oral surgery. The study will observe how their speech changes before and after treatment. There is no randomization or intervention involved.

Aim 1: Qualify the prevalence of auditory and visual speech distortions in the DFD population. Aim 2: Quantitatively evaluate the first spectral moment (kHz) of four articulating consonant sounds (/t/, /k/, /s/, and /?/ pronounced "sh"). Quantify and analyze the changes in speech distortions for orthognathic patients pre and post-operation. Aim 3: Evaluate tongue posture during speech with patients from Aim 2 pre and post-operation.


Participants: Patients of the UNC dentofacial disharmony (DFD) clinic who have undergone orthognathic surgery for correction of jaw disharmonies.

Procedures (methods):

Patients will be recorded pronouncing a series of words highlighting a range of phonetic contrasts including --/s-sh/ and t-k/. words each presented on a screen using PowerPoint, 3 times each with carrier phrases). Recordings include an acoustic feed, a profile video of the jaws plus lips, and ultrasound imaging of the tongue relative to the palate and jaws. Research staff will score audio recordings according to their spectral moments and ultrasound recordings according to tongue movement and associate findings with degree of dental discrepancy. Prospective recordings will be collected at three timepoints: 1-3 months prior to jaw surgery, 3-8 months and 9-15 months post-operation for 60 overbite, 60 openbite and 60 underbite DFD patients. These time points were selected to co-occur with patients' surgical check-ups to ensure reliable data collection while minimizing confounding factors such as severe facial swelling and splint placement which occur immediately after surgery.

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Study Type : Observational
Estimated Enrollment : 180 participants
Observational Model: Cohort
Time Perspective: Prospective
Official Title: Orthognathic Speech Pathology: Phonetic Contrasts of Patients With Dentofacial Discrepancies With Pre- and Post-Treatment Analyses
Estimated Study Start Date : February 2020
Estimated Primary Completion Date : December 2024
Estimated Study Completion Date : December 2024

Group/Cohort Intervention/treatment
Dentofacial Disharmony Patients
Dentofacial disharmony patients who are seeking jaw surgery in UNC oral and maxillofacial surgery department and are seen in UNC orthodontic dentofacial disharmony clinic.
Other: Orthognathic surgery and Orthodontics
This study is observational. All subjects identified to participate will be undergoing orthognathic jaw surgery and orthodontic treatment.

Primary Outcome Measures :
  1. Change in Speech Distortion Phonemes over Time [ Time Frame: pre-operation through 9-15 months post-operation ]
    Audio recordings of consonant phonemes will be quantitatively analyzed using spectral moment analysis yielding mean values.

  2. Change in Quantitative Tongue Gestures over Time [ Time Frame: pre-operation through 9-15 months post-operation ]
    Ultrasound analysis of tongue posture to quantitatively describe tongue position during speech.

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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Ages Eligible for Study:   15 Years to 40 Years   (Child, Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
The study population includes healthy patients who present in our oral surgery and/or orthodontic dentofacial disharmony clinics with skeletal underbites, open bites, and/or excessive overjet. These patients have decided (prior to our study) to pursue orthodontic treatment combined with orthognathic surgery to address their jaw disproportions.

Inclusion Criteria:

  • Jaw surgery patient at UNC with a skeletal open bite, underbite or overjet greater than 5mm.
  • Age 15-40 years

Exclusion Criteria:

  • Hearing loss
  • Learned English as a second language
  • Significant regional accent, as characterized by a speech pathologist
  • Developmental delay, performing several grade levels below age bracket
  • history of craniofacial disorder
  • genetic syndrome associated with known craniofacial presentation
  • history of craniofacial trauma
  • history of prior craniofacial surgery (excluding extractions and dental procedures)
  • Jaw surgery without fixed orthodontic appliances

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT04117360

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Contact: Laura A Jacox, PhD, DMD, MS 847- 702-0988
Contact: Sherrill T Phillips, BS

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United States, North Carolina
University of North Carolina Recruiting
Chapel Hill, North Carolina, United States, 27514
Contact: Laura A Jacox, DMD, PhD, MS    847-702-0988   
Principal Investigator: Laura A Jacox, DMD, PhD, MS         
Sponsors and Collaborators
University of North Carolina, Chapel Hill
North Carolina State University
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Principal Investigator: Laura A Jacox, PhD, DMD, MS Professor

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Responsible Party: University of North Carolina, Chapel Hill Identifier: NCT04117360    
Other Study ID Numbers: 19-1196
First Posted: October 7, 2019    Key Record Dates
Last Update Posted: February 5, 2020
Last Verified: February 2020
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No
Plan Description: Our data includes video, audio and ultrasound recordings. This is not data that can be shared and maintained confidentially while meeting HIPAA guidelines.

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Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by University of North Carolina, Chapel Hill:
Dentofacial Disharmony
Skeletal malocclusion
Speech Sound Disorder
Spectral Moment Analysis
Tongue Ultrasound
Orthognathic Surgery
Additional relevant MeSH terms:
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Dentofacial Deformities
Speech Disorders
Speech Sound Disorder
Pathologic Processes
Congenital Abnormalities
Tooth Diseases
Stomatognathic Diseases
Language Disorders
Communication Disorders
Neurobehavioral Manifestations
Neurologic Manifestations
Nervous System Diseases
Signs and Symptoms
Neurodevelopmental Disorders
Mental Disorders
Maxillofacial Abnormalities
Craniofacial Abnormalities
Musculoskeletal Abnormalities
Musculoskeletal Diseases
Stomatognathic System Abnormalities