Trial of Bilateral Sagittal Split Osteotomy Induced Paresthesia Using Ultrasonic vs. Reciprocating Saw Instrumentation

Not Applicable

Completed

Conditions: Paresthesia
Nerve Injury
Fracture
Mandibular Prognathism
Nerve Entrapments
Mandibular Nerve Injuries
Mandibular Hyperplasia
Mandibular Hypoplasia
Surgical Complication
Mandibular Retrognathism

Brief Summary: The aim of this prospective study is to analyze the postoperative paresthesias experienced in patients who undergo bilateral sagittal split osteotomies (BSSO) using an ultrasonic saw, versus a reciprocating saw. Patients included in the study are ages 15-45 scheduled to undergo BSSO surgery at the University of California, San Francisco. One side of the patient's mandible will be instrumented with either the Stryker Sonopet ultrasonic saw or traditional reciprocating saw, while the other side will receive the remaining intervention (determined via randomization on the day of surgery). Patient paresthesias will then be analyzed on each side for 3 months postoperatively (at postoperative days: 1, 7, 14, 28, and 84). Sensory examinations will be carried out by blinded examiners using von Frey hairs and two point discrimination testing. Patients will also subjectively rate their sensation on each side. The results will then be analyzed to determine if patient paresthesias, including the severity and duration, differed depending on which instrument was used, the ultrasonic or reciprocating saw.

Recruitment & Eligibility

Inclusion Criteria

Must be undergoing bilateral sagittal split osteotomy surgery with Dr. Saghezchi at UCSF
Must agree to return for all follow up visits.
Must not have any preexisting V3 nerve paresthesia
Must be below the age of 45.

Exclusion Criteria

Persons with preexisting V3 nerve paresthesias
Pre-pubertal children will be excluded (per routine practice for this type of surgery).
Patients with syndromic genetic conditions that demonstrate clearly different anatomy in the two sides of their jaws will be excluded since the two sides may not be "exchangeable".

Primary Outcome Measures

Name	Time	Method
Postoperative Hypoesthesia Experienced at 3months	Within 15 days of exact 3 months post-operation	Count of patient mandibles who exhibited \\any\\ hypoesthesia at 3months post-operation (i.e. VFH does not equal 0.008g). VFH filaments measure the minimum weight which a dermatome in question can sense. In this study, the measurements were designed to have the following range: 0.008g, 0.02g, 0.04g, 0.07g, 0.16g, 0.4g, 0.6g, 1g, 1.4g, 2g, 4g, 6g, 8g, 10g, 15g, with 0.008g being no neurosensory deficit. Although 28 persons completed the study, only 21 patients presented for their 3 month followup time, which was defined as with-in 15 days of 90th day after operation. Therefore, the denominator for this outcome is 21, for each intervention arm. The numerator is the number of Left or Right chin areas that exhibited less than "normal" sensation.

Secondary Outcome Measures

Name	Time	Method
Unfavorable Fracture	This outcome occurs during the surgery. It was measured on the same day.	When a saggital split osteotomy is performed, a controlled fracture of the mandibular ramus is induced which follows an exact intended path of fracture. An unfavorable fracture is one that does not follow this exact path of fracture, and needs to be surgically mended. An unfavorable fracture is associated with poorer post-operative recovery.

Locations (2): University of California, San Francisco Medical Center
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San Francisco, California, United States
UCSF Benioff Children's Hospital
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San Francisco, California, United States
University of California, San Francisco Medical Center
🇺🇸San Francisco, California, United States