Use of TENS for the Recovery of Oral Function After Orthognathic Surgery

Study Overview
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Brief Summary
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Oral functions of patients are markedly diminished immediately after orthognathic surgery, and novel approaches are needed to accelerate their recovery. The aim of this study is to examine the usefulness of weekly applications of transcutaneous electrical nerve stimulation (TENS) for this purpose, based on evidence of its effectiveness in other types of patients with muscle alterations. The main objective is to determine whether weekly TENS applications can increase the bite force and jaw opening in patients undergoing orthognathic surgery and decrease their pain and inflammation

Detailed Description
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A single-blind randomized clinical trial will be conducted in patients scheduled for orthognathic surgery, divided between experimental and control groups. Participants will be selected by non-probabilistic sampling of consecutive patients until the estimated sample size is reached. All patients have a skeletal and facial deformity amenable to surgery after a pre-surgical orthodontic period. Patients will be randomly assigned to the experimental group for TENS application or the control group for sham-TENS and the researcher responsible for data analyses will be blinded also. Four variables will be measured: Maximum Jaw Opening using a digital dental caliber, Bite force measured using Dental Prescale Fuji® film, Pain using a visual analog scale (VAS) and facial inflammation using a soft ruler adapted to the contour of the patient's face. Data will be gathered from all patients on jaw opening, bite force, inflammation, and pain before surgery and at 7, 14, 21, and 28 days post-surgery, conducting measurements both before and after the TENS/sham-TENS session. TENS will be applied in an identical manner to all patients in both groups and kept in position for the same time period (30 min); however, the device will be not switched on for the control group, and the stimulation intensity will be adjusted for those in the experimental group to the maximum that did not cause discomfort or areas of contraction, maintaining this stimulation intensity and frequency throughout the 30-min session. Each participant will submit to a weekly TENS a weekly TENS or sham-TENS session on the same day of the week during a four-week period

Official Title
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Use of Transcutaneous Electrical Nerve Stimulation (TENS) for the Recovery of Oral Function After Orthognathic Surgery

Conditions
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Orthognathic Surgery, Physiology, Transcutaneous Electric Nerve Stimulation

Intervention / Treatment
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* Device: transcutaneous electrical nerve stimulation (TENS):Enraf Nonius® S82 model


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: programing of bimaxillary or mandibular orthognathic surgery no previous or concomitant surgery for temporo-mandibular disorders no presence of complex syndromes no presence of muscle or nervous disorders or receipt of medication for such disorders Exclusion Criteria: impossibility to attend follow-up appointments refusal of informed consent

Ages Eligible for Study
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Minimum Age: 22 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Experimental group<br>transcutaneous electrical nerve stimulation (TENS) is applied | Device: transcutaneous electrical nerve stimulation (TENS):Enraf Nonius® S82 model<br>* Will be used TENS device with a maximum frequency of 120 Hz and an intensity range of 0 to 99.5 milliampere. TENS electrodes (diameter 35-52 mm) will be placed bilaterally on mandibular elevator muscles, on the superficial masseter muscle above the gonial angle, and bilaterally on the anterior temporal muscle. The device will be applied in an identical manner to all patients in both groups and kept in position for the same time period (30 min) and for the control group the the device will be not switched on<br>|
| No Intervention: Control group<br>no intervention | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Bite force | Bite force will be measured using Dental Prescale Fuji® film placed between the occlusal surfaces of the two arches, and the patient will be asked to bite as strongly as possible for 5 sec and the best-defined tooth print will be photographed with a Canon® EOS 500 camera (RAW format, F32, and annular Flash) at the minimum distance permitted by the 75-macro lens. The image will be processed in a Mac computer to obtain the color value according to the Cie L*a*b* (CIELAB) scale, which gives the color a numerical value.The corresponding pressure units (Megapascals, MPa) will be calculated according to Dental Prescale specifications, and the bite force (in Newtons [N]) will be obtained by using the following formula: Bite Force= Bite Pressure (MPa) x mm2 print surface. | Measurements will be taken baseline (before surgery) | 
| Bite force | Bite force will be measured using Dental Prescale Fuji® film placed between the occlusal surfaces of the two arches, and the patient will be asked to bite as strongly as possible for 5 sec and the best-defined tooth print will be photographed with a Canon® EOS 500 camera (RAW format, F32, and annular Flash) at the minimum distance permitted by the 75-macro lens. The image will be processed in a Mac computer to obtain the color value according to the Cie L*a*b* (CIELAB) scale, which gives the color a numerical value.The corresponding pressure units (Megapascals, MPa) will be calculated according to Dental Prescale specifications, and the bite force (in Newtons [N]) will be obtained by using the following formula: Bite Force= Bite Pressure (MPa) x mm2 print surface. | Measurements will be taken at 7 days after surgery | 
| Bite force | Bite force will be measured using Dental Prescale Fuji® film placed between the occlusal surfaces of the two arches, and the patient will be asked to bite as strongly as possible for 5 sec and the best-defined tooth print will be photographed with a Canon® EOS 500 camera (RAW format, F32, and annular Flash) at the minimum distance permitted by the 75-macro lens. The image will be processed in a Mac computer to obtain the color value according to the Cie L*a*b* (CIELAB) scale, which gives the color a numerical value.The corresponding pressure units (Megapascals, MPa) will be calculated according to Dental Prescale specifications, and the bite force (in Newtons [N]) will be obtained by using the following formula: Bite Force= Bite Pressure (MPa) x mm2 print surface. | Measurements will be taken at 14 days after surgery | 
| Bite force | Bite force will be measured using Dental Prescale Fuji® film placed between the occlusal surfaces of the two arches, and the patient will be asked to bite as strongly as possible for 5 sec and the best-defined tooth print will be photographed with a Canon® EOS 500 camera (RAW format, F32, and annular Flash) at the minimum distance permitted by the 75-macro lens. The image will be processed in a Mac computer to obtain the color value according to the Cie L*a*b* (CIELAB) scale, which gives the color a numerical value.The corresponding pressure units (Megapascals, MPa) will be calculated according to Dental Prescale specifications, and the bite force (in Newtons [N]) will be obtained by using the following formula: Bite Force= Bite Pressure (MPa) x mm2 print surface. | Measurements will be taken at 21 days after surgery | 
| Bite force | Bite force will be measured using Dental Prescale Fuji® film placed between the occlusal surfaces of the two arches, and the patient will be asked to bite as strongly as possible for 5 sec and the best-defined tooth print will be photographed with a Canon® EOS 500 camera (RAW format, F32, and annular Flash) at the minimum distance permitted by the 75-macro lens. The image will be processed in a Mac computer to obtain the color value according to the Cie L*a*b* (CIELAB) scale, which gives the color a numerical value.The corresponding pressure units (Megapascals, MPa) will be calculated according to Dental Prescale specifications, and the bite force (in Newtons [N]) will be obtained by using the following formula: Bite Force= Bite Pressure (MPa) x mm2 print surface. | Measurements will be taken at 28 days after surgery | 
| Jaw opening | Jaw opening will be evaluated with patients seated vertically upright in the dental chair, using a digital dental caliber (Model R 100110, Mestra®) to measure the maximum opening from the incisal margin of upper central incisors to the incisal margin of lower incisors, adding the amount (in mm) of overbite or subtracting the amount (in mm) of open bite in occlusion. | Measurements will be taken baseline (before surgery) | 
| Jaw opening | Jaw opening will be evaluated with patients seated vertically upright in the dental chair, using a digital dental caliber (Model R 100110, Mestra®) to measure the maximum opening from the incisal margin of upper central incisors to the incisal margin of lower incisors, adding the amount (in mm) of overbite or subtracting the amount (in mm) of open bite in occlusion. | Measurements will be taken at 7 days after surgery | 
| Jaw opening | Jaw opening will be evaluated with patients seated vertically upright in the dental chair, using a digital dental caliber (Model R 100110, Mestra®) to measure the maximum opening from the incisal margin of upper central incisors to the incisal margin of lower incisors, adding the amount (in mm) of overbite or subtracting the amount (in mm) of open bite in occlusion. | Measurements will be taken at 14 days after surgery | 
| Jaw opening | Jaw opening will be evaluated with patients seated vertically upright in the dental chair, using a digital dental caliber (Model R 100110, Mestra®) to measure the maximum opening from the incisal margin of upper central incisors to the incisal margin of lower incisors, adding the amount (in mm) of overbite or subtracting the amount (in mm) of open bite in occlusion. | Measurements will be taken at 21 days after surgery | 
| Jaw opening | Jaw opening will be evaluated with patients seated vertically upright in the dental chair, using a digital dental caliber (Model R 100110, Mestra®) to measure the maximum opening from the incisal margin of upper central incisors to the incisal margin of lower incisors, adding the amount (in mm) of overbite or subtracting the amount (in mm) of open bite in occlusion. | Measurements will be taken at 28 days after surgery | 
| Pain (VAS) | Pain perceived by patients while autonomously opening and closing their jaws will be evaluated using a visual analog scale (VAS) from 0 (least pain value) to 10 (value of greater pain). | Measurements will be taken baseline (before surgery) | 
| Pain (VAS) | Pain perceived by patients while autonomously opening and closing their jaws will be evaluated using a visual analog scale (VAS) from 0 (least pain value) to 10 (value of greater pain). | Measurements will be taken at 7 days after surgery | 
| Pain (VAS) | Pain perceived by patients while autonomously opening and closing their jaws will be evaluated using a visual analog scale (VAS) from 0 (least pain value) to 10 (value of greater pain). | Measurements will be taken at 14 days after surgery | 
| Pain (VAS) | Pain perceived by patients while autonomously opening and closing their jaws will be evaluated using a visual analog scale (VAS) from 0 (least pain value) to 10 (value of greater pain). | Measurements will be taken at 21 days after surgery | 
| Pain (VAS) | Pain perceived by patients while autonomously opening and closing their jaws will be evaluated using a visual analog scale (VAS) from 0 (least pain value) to 10 (value of greater pain). | Measurements will be taken at 28 days after surgery | 
| Inflammation | Inflammation will be measured (in mm) with patients seated upright in the dental chair, using a soft ruler to obtain a horizontal measurement from the lower border of the earlobe to the corner of the mouth and a vertical measurement from the gonial angle to the outer canthus of the eye. The soft ruler will be adapted to the contour of the patient's face without exerting any pressure. | Measurements will be taken baseline (before surgery) | 
| Inflammation | Inflammation will be measured (in mm) with patients seated upright in the dental chair, using a soft ruler to obtain a horizontal measurement from the lower border of the earlobe to the corner of the mouth and a vertical measurement from the gonial angle to the outer canthus of the eye. The soft ruler will be adapted to the contour of the patient's face without exerting any pressure. | Measurements will be taken at 7 days after surgery | 
| Inflammation | Inflammation will be measured (in mm) with patients seated upright in the dental chair, using a soft ruler to obtain a horizontal measurement from the lower border of the earlobe to the corner of the mouth and a vertical measurement from the gonial angle to the outer canthus of the eye. The soft ruler will be adapted to the contour of the patient's face without exerting any pressure. | Measurements will be taken at 14 days after surgery | 
| Inflammation | Inflammation will be measured (in mm) with patients seated upright in the dental chair, using a soft ruler to obtain a horizontal measurement from the lower border of the earlobe to the corner of the mouth and a vertical measurement from the gonial angle to the outer canthus of the eye. The soft ruler will be adapted to the contour of the patient's face without exerting any pressure. | Measurements will be taken at 21 days after surgery | 
| Inflammation | Inflammation will be measured (in mm) with patients seated upright in the dental chair, using a soft ruler to obtain a horizontal measurement from the lower border of the earlobe to the corner of the mouth and a vertical measurement from the gonial angle to the outer canthus of the eye. The soft ruler will be adapted to the contour of the patient's face without exerting any pressure. | Measurements will be taken at 28 days after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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oral function