title: Low to high oblique ramus piezoosteotomy: a pilot study.
abstract: Two major drawbacks of classical bilateral sagittal split osteotomy (BSSO) are occasional inferior alveolar nerve damage and bad splits. In order to avoid these two well-known disadvantages and benefit from ultrasonic bone cutting, a low-to-high oblique piezoosteotomy (LHO) was developed from Schlössmann's 1922 high oblique osteotomy, clinically evaluated with a standard and a novel osteosynthesis system. Eighty-five patients were retrospectively evaluated, 23 with an LHO osteotomy with standard osteosynthesis, 33 LHO with a dedicated plate osteosynthesis and compared to 29 patients with BSSO and standard osteosyntheses. The mean mandibular advancement in the LHO standard osteosynthesis/LHO dedicated plate osteosynthesis/BSSO collectives was 4.7 ± 2.5/7.8 ± 7.1/4.1 ± 2.8 mm, the mean one year relapse 2.6 ± 0.8 (p = 0.58)/1.4 ± 1.4 (p = 0.28)/2.1 ± 1.4 mm; the mean mandibular setback was 6.9 ± 3.6/7.7 ± 4.1/8.1 ± 4.9 mm and the one year relapse 2.9 ± 2.9 (p = 0.16)/1.4 ± 1.0 (p = 0.38)/1.5 ± 1.9 mm; clockwise rotation of the mandible was 5.2 ± 3.2/6.3 ± 5.1/10.2 ± 6.9°, the one year relapse 2.7 ± 1.2 (p = 0.18)/2.1 ± 1.7 (p = 0.09)/11.4 ± 9.3°; counterclockwise rotation averaged 6.4 ± 3.2/6.5 ± 7.9/6.5 ± 6.1° with a mean one year relapse of 3.3 ± 0.6 (p = 0.37)/3.7 ± 1.9 (p = 0.21)/4.5 ± 6.2°. LHO had 3%, BSSO 5% three months postoperative inferior alveolar nerve deficit (p = 0.17). The operation time was significantly shorter when LHO and dedicated plates were used compared to BSSO. Two broken conventional plates occurred in LHO, which stimulated the development of the dedicated plates used, one in BSSO; four bad splits in BSSO and two in LHO. Reosteosyntheses were performed using the newly developed dedicated "orthognathics" plate. LHO was successfully performed, easier and faster than BSSO. Gonial angle modifications were possible due to the oblique cut. Postoperative stability appears sufficient for moderate repositioning with a lower incidence of bad split and inferior alveolar nerve irritation, moreover blood loss was reduced. Since 2 standard miniplate fractures occurred in LHO, the "orthognathics" osteosynthesis was developed, applied and no further osteosynthesis fractures were seen.
authors: Cranio-Maxillofacial and Plastic Facial Surgery (Head: Robert Sader, MD, DMD, PhD, FEBOMFS), J. W. Goethe-University of Frankfurt Medical Centre, Frankfurt, Germany. Electronic address: constantinlandes@googlemail.com.
authors: Constantin
authors: C
authors: Landes
authors: Cranio-Maxillofacial and Plastic Facial Surgery (Head: Robert Sader, MD, DMD, PhD, FEBOMFS), J. W. Goethe-University of Frankfurt Medical Centre, Frankfurt, Germany.
authors: Andreas
authors: A
authors: Tran
authors: Cranio-Maxillofacial and Plastic Facial Surgery (Head: Robert Sader, MD, DMD, PhD, FEBOMFS), J. W. Goethe-University of Frankfurt Medical Centre, Frankfurt, Germany.
authors: Alexander
authors: A
authors: Ballon
authors: Cranio-Maxillofacial and Plastic Facial Surgery (Head: Robert Sader, MD, DMD, PhD, FEBOMFS), J. W. Goethe-University of Frankfurt Medical Centre, Frankfurt, Germany.
authors: Gregor
authors: G
authors: Santo
authors: Cranio-Maxillofacial and Plastic Facial Surgery (Head: Robert Sader, MD, DMD, PhD, FEBOMFS), J. W. Goethe-University of Frankfurt Medical Centre, Frankfurt, Germany.
authors: Florian
authors: F
authors: Schübel
authors: Cranio-Maxillofacial and Plastic Facial Surgery (Head: Robert Sader, MD, DMD, PhD, FEBOMFS), J. W. Goethe-University of Frankfurt Medical Centre, Frankfurt, Germany.
authors: Robert
authors: R
authors: Sader
mesh_terms: D000328:Adult; D016063:Blood Loss, Surgical; D001860:Bone Plates; D002508:Cephalometry / Q000379:methods; D004867:Equipment Design; D004868:Equipment Failure; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006987:Hypesthesia / Q000209:etiology; D008297:Male; D008312:Malocclusion, Angle Class II / Q000601:surgery; D008313:Malocclusion, Angle Class III / Q000601:surgery; D019186:Mandibular Advancement / Q000295:instrumentation / Q000379:methods; D008340:Mandibular Nerve / Q000503:physiopathology; D024343:Open Bite / Q000601:surgery; D061646:Operative Time; D059229:Osteotomy, Sagittal Split Ramus / Q000295:instrumentation / Q000379:methods*; D059745:Piezosurgery / Q000295:instrumentation / Q000379:methods*; D010865:Pilot Projects; D012008:Recurrence; D012189:Retrospective Studies; D012399:Rotation; D014110:Touch / Q000502:physiology; D055815:Young Adult
keywords: Low-to-high mandibular osteotomy; Mandibular osteotomy; Orthognathic surgery; Piezoosteotomy; Piezosurgery