An interventional study of Sonopet ultrasonic saw and Reciprocating saw in Surgical Complication, Paresthesia and Fracture, sponsored by University of California, San Francisco. Completed at 2 sites in United States. Open to participants aged Up to 45 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-06-04.
Sponsored by University of California, San Francisco · Not applicable, Interventional, and Supportive care
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.
66 studies on the registry are indexed under Paresthesia; 14 are open to participants now.
This study's enrollment of 32 is below the median of 48 across 52 interventional studies indexed under Paresthesia.
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Exclusion Criteria:
The traditional surgical instrument used for cutting bilateral sagittal split osteotomies
Device: Reciprocating saw
This instrument is being compared to the reciprocating saw
Device: Sonopet ultrasonic saw
Ultrasonic saw to be used on a randomized side of the mandible, reciprocating saw will be used on other side
See above description
Postoperative Hypoesthesia Experienced at 3months
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.
Time frame: Within 15 days of exact 3 months post-operation
Unfavorable Fracture
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.
Time frame: This outcome occurs during the surgery. It was measured on the same day.
Please note that since this is a pair-matched "split-mouth" study, where each participant was in both arms of the study since their left and right mandibles were the units receiving the different interventions in the study. Therefore, the total persons enrolled was 32 persons, while the total mandibles enrolled was 64.
| Milestone | Reciprocating Saw | Sonopet Ultrasonic Saw |
|---|---|---|
| Started | 32 | 32 |
| Completed | 28 | 28 |
| Not completed | 4 | 4 |
| Withdrew: Lost to follow-up | 4 | 4 |
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.
| Left or Right Chin Area | Reciprocating Saw | Sonopet Ultrasonic Saw |
|---|---|---|
| Postoperative Hypoesthesia Experienced at 3months | 8 | 3 |
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.
| Mandibular rami | Reciprocating Saw | Sonopet Ultrasonic Saw |
|---|---|---|
| Unfavorable Fracture | 2 | 0 |
Collected over At a minimum each participant who was not lost to follow up was followed for three months (defined as 85 - 115 days) after their operation. However, patients were followed as long as they return for assessment of their orthognathic surgery. The follow up of participants who completed the study ranged from 85 days to 419 days.. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Reciprocating Saw | 0/28 (0%) | 0/28 (0%) | 4/28 (14.3%) |
| Sonopet Ultrasonic Saw | 0/28 (0%) | 0/28 (0%) | 1/28 (3.6%) |
| Event | Reciprocating Saw | Sonopet Ultrasonic Saw |
|---|---|---|
| Transaction of Inferior Alveolar Nerve (IAN), which provides sensation to the chin areaSurgical and medical procedures | 4/28 | 1/28 |
Each study participant was assigned to both study arms, while only one of their two mandibular rami was assigned to that study arm, and received that treatment. Since 4 persons were lost to followup, the baseline participants groups only contains 28 persons.
| Age, Continuous(years) | Reciprocating Saw | Sonopet Ultrasonic Saw | Total |
|---|---|---|---|
| Mean | 25.95 ± 9.8 | 25.95 ± 9.8 | 25.95 ± 9.8 |
| Sex: Female, Male(Participants) | Reciprocating Saw | Sonopet Ultrasonic Saw | Total |
|---|---|---|---|
| Female | 15 | 15 | 30 |
| Male | 13 | 13 | 26 |
| Race/Ethnicity, Customized(Participants) | Reciprocating Saw | Sonopet Ultrasonic Saw | Total |
|---|---|---|---|
| Caucasian | 13 | 13 | 26 |
| African American | 1 | 1 | 2 |
| Latinx | 8 | 8 | 16 |
| Asian | 6 | 6 | 12 |
| Normal Baseline VFH Score (Lightest VFH Filament sensed has a weight of 0.008g)(Mandibular Rami) | Reciprocating Saw | Sonopet Ultrasonic Saw | Total |
|---|---|---|---|
| Count of units | 23 | 22 | 45 |
PDFs hosted by the registry, ClinicalTrials.gov.
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