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Total mandibular subapical osteotomy: modification of the technique
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British Journal of Oral and Maxillofacial Surgery 47 (2009) 629–630
Technical note
Total mandibular subapical osteotomy: modification of the technique Ricardo I. Mohammed-Ali a,∗ , Andrew Schache b , S. Walsh b , Kenneth Sneddon b a b
Oral & Maxillofacial Surgery, East Midlands Rotation, North Trent, 50 Ashford Rise, Belper, Derbyshire, DE56 1TJ, United Kingdom The Queen Victoria Hospital NHS Foundation Trust, East Grinstead, RH19 3DZ, United Kingdom
Accepted 25 November 2008 Available online 6 March 2009 Keywords: Total mandibular subapical osteotomy; Inferior alveolar nerve; Bilateral sagittal split osteotomy
Kole1 described operations on the alveolar ridge to correct occlusal abnormalities, and MacIntosh2 first described the technique of total subapical osteotomy in 1974. Since then several modifications have been described.3–7 The indications are: mandibular dentoalveolar hypoplasia with good projection of the chin, mandibular vertical alveolar deficiency, lateral open bite deformity, condylar agenesis and hypoplasia, infantile open bite, and correction of relapse after previous ramus osteotomy. Eliades et al. reported a patient in whom a total mandibular subapical osteotomy was combined with the bilateral sagittal split osteotomy (BSSO) to reduce the extent to which the mandible would have to be advanced with the BSSO alone.8 We describe a modification of the total mandibular subapical osteotomy including a different technique for decortication of the inferior alveolar nerve. We have used the BSSO with the sole aim of exposing the inferior alveolar nerve proximally and limiting the length of dissection of the inferior dental canal and the risk to the nerve. The sagittal split exposes the main length of the nerve from the lingula to within 2 cm of the mental foramen. The remaining 2 cm of nerve can be decorticated easily by making monocortical parallel bony cuts over the neurovascular bundle with direct vision of the proximal and distal extent of the nerve. We found this modification of the technique to be precise, technically uncomplicated, and efficient in reducing what can be a time-consuming process. A curvilinear incision was made in the buccal sulcus from one ascending ramus to the other. The incision was carried ∗
Corresponding author. Tel.: +44 7810614803. E-mail address: [email protected] (R.I. Mohammed-Ali).
Fig. 1. White arrow showing the inferior alveolar nerve after the BSSO, and the black line indicating the remaining 2 cm within the mandibular canal to be decorticated.
down to bone and, using blunt dissection, the lingula and the neurovascular bundle were identified together with the mental foramen. The bony cuts for a BSSO were, however, made before the split was completed and four-hole plates with screws were placed bilaterally on the buccal cortex where the mandible would be fixed. These plates were then removed and the sagittal split completed, allowing the final position of the
0266-4356/$ – see front matter © 2009 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
doi:10.1016/j.bjoms.2008.11.017
630
R.I. Mohammed-Ali et al. / British Journal of Oral and Maxillofacial Surgery 47 (2009) 629–630
mandible to remain unchanged. On completion of the BSSO the inferior alveolar nerve was released bilaterally (Fig. 1). This exposed the main length of the nerve from the lingula to within 2 cm of the mental foramen. The remaining 2 cm of nerve was decorticated by making parallel bony cuts over the neurovascular bundle with direct vision of the proximal and distal extent of the nerve (Fig. 2). The inferior alveolar nerve was subsequently isolated and protected bilaterally. The subapical osteotomy was then done and the dentoalveolar segment advanced. The BSSO was fixed using the plates and screws in the position previously drilled (Fig. 3). The occlusion was held with an acrylic wafer and the dentoalveolar segment was fixed with one inverted L-shaped plate on each side of the mandible and a genioplasty plate anteriorly. The resulting bony gap created by advancing the dentoalveolar segment was grafted with cancellous bone chips from the iliac crest.
References
Fig. 2. The inferior alveolar nerve decorticated and released.
Fig. 3. Sagittal split plated without any change in the position of the mandible after total mandibular subapical osteotomy.
1. Kole H. Surgical operations on the alveolar ridge to correct occlusal abnormalities. Oral Surg Oral Med Oral Pathol 1959;12:515–29. 2. MacIntosh RB. Total mandibular alveolar osteotomy. J Maxillofacial Surg 1974;2:210–8. 3. Pangrazio-Kulbersh V, MacIntosh RB. Total mandibular alveolar osteotomy: an alternative choice to other surgical procedures. Am J Orthod 1985;87:319–37. 4. Murray RB. Mandibular sagittal subapical osteotomy: a case study. Am J Orthod 1980;77:469–85. 5. Booth DF, Dietz VS, Gainelly AA. Correction of Class II malocclusion by combined sagittal ramus and subapical body osteotomy. J Oral Surg 1976;34:630–4. 6. Dietz VS, Gainelly AA, Booth DF. Surgical orthodontics in the treatment of Class II, division II malocclusion: a case report. Am J Orthod 1977;71:309–16. 7. Frost DE, Fonseca RJ, Koutnik AW. Total subapical sub-osteotomy: a modification of the surgical technique. Int J Adult Orthodon Orthognath Surg 1986;1:119–28. 8. Eliades T, Hegdvedt AK, Larsen PE, Herpy AK. Treatment of Class II division 2 malocclusion with combined bilateral sagittal split osteotomy and total subapical osteotomy. Int J Adult Orthodon Orthognath Surg 1994;9:213–22.
British Journal of Oral and Maxillofacial Surgery 47 (2009) 629–630
Technical note
Total mandibular subapical osteotomy: modification of the technique Ricardo I. Mohammed-Ali a,∗ , Andrew Schache b , S. Walsh b , Kenneth Sneddon b a b
Oral & Maxillofacial Surgery, East Midlands Rotation, North Trent, 50 Ashford Rise, Belper, Derbyshire, DE56 1TJ, United Kingdom The Queen Victoria Hospital NHS Foundation Trust, East Grinstead, RH19 3DZ, United Kingdom
Accepted 25 November 2008 Available online 6 March 2009 Keywords: Total mandibular subapical osteotomy; Inferior alveolar nerve; Bilateral sagittal split osteotomy
Kole1 described operations on the alveolar ridge to correct occlusal abnormalities, and MacIntosh2 first described the technique of total subapical osteotomy in 1974. Since then several modifications have been described.3–7 The indications are: mandibular dentoalveolar hypoplasia with good projection of the chin, mandibular vertical alveolar deficiency, lateral open bite deformity, condylar agenesis and hypoplasia, infantile open bite, and correction of relapse after previous ramus osteotomy. Eliades et al. reported a patient in whom a total mandibular subapical osteotomy was combined with the bilateral sagittal split osteotomy (BSSO) to reduce the extent to which the mandible would have to be advanced with the BSSO alone.8 We describe a modification of the total mandibular subapical osteotomy including a different technique for decortication of the inferior alveolar nerve. We have used the BSSO with the sole aim of exposing the inferior alveolar nerve proximally and limiting the length of dissection of the inferior dental canal and the risk to the nerve. The sagittal split exposes the main length of the nerve from the lingula to within 2 cm of the mental foramen. The remaining 2 cm of nerve can be decorticated easily by making monocortical parallel bony cuts over the neurovascular bundle with direct vision of the proximal and distal extent of the nerve. We found this modification of the technique to be precise, technically uncomplicated, and efficient in reducing what can be a time-consuming process. A curvilinear incision was made in the buccal sulcus from one ascending ramus to the other. The incision was carried ∗
Corresponding author. Tel.: +44 7810614803. E-mail address: [email protected] (R.I. Mohammed-Ali).
Fig. 1. White arrow showing the inferior alveolar nerve after the BSSO, and the black line indicating the remaining 2 cm within the mandibular canal to be decorticated.
down to bone and, using blunt dissection, the lingula and the neurovascular bundle were identified together with the mental foramen. The bony cuts for a BSSO were, however, made before the split was completed and four-hole plates with screws were placed bilaterally on the buccal cortex where the mandible would be fixed. These plates were then removed and the sagittal split completed, allowing the final position of the
0266-4356/$ – see front matter © 2009 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
doi:10.1016/j.bjoms.2008.11.017
630
R.I. Mohammed-Ali et al. / British Journal of Oral and Maxillofacial Surgery 47 (2009) 629–630
mandible to remain unchanged. On completion of the BSSO the inferior alveolar nerve was released bilaterally (Fig. 1). This exposed the main length of the nerve from the lingula to within 2 cm of the mental foramen. The remaining 2 cm of nerve was decorticated by making parallel bony cuts over the neurovascular bundle with direct vision of the proximal and distal extent of the nerve (Fig. 2). The inferior alveolar nerve was subsequently isolated and protected bilaterally. The subapical osteotomy was then done and the dentoalveolar segment advanced. The BSSO was fixed using the plates and screws in the position previously drilled (Fig. 3). The occlusion was held with an acrylic wafer and the dentoalveolar segment was fixed with one inverted L-shaped plate on each side of the mandible and a genioplasty plate anteriorly. The resulting bony gap created by advancing the dentoalveolar segment was grafted with cancellous bone chips from the iliac crest.
References
Fig. 2. The inferior alveolar nerve decorticated and released.
Fig. 3. Sagittal split plated without any change in the position of the mandible after total mandibular subapical osteotomy.
1. Kole H. Surgical operations on the alveolar ridge to correct occlusal abnormalities. Oral Surg Oral Med Oral Pathol 1959;12:515–29. 2. MacIntosh RB. Total mandibular alveolar osteotomy. J Maxillofacial Surg 1974;2:210–8. 3. Pangrazio-Kulbersh V, MacIntosh RB. Total mandibular alveolar osteotomy: an alternative choice to other surgical procedures. Am J Orthod 1985;87:319–37. 4. Murray RB. Mandibular sagittal subapical osteotomy: a case study. Am J Orthod 1980;77:469–85. 5. Booth DF, Dietz VS, Gainelly AA. Correction of Class II malocclusion by combined sagittal ramus and subapical body osteotomy. J Oral Surg 1976;34:630–4. 6. Dietz VS, Gainelly AA, Booth DF. Surgical orthodontics in the treatment of Class II, division II malocclusion: a case report. Am J Orthod 1977;71:309–16. 7. Frost DE, Fonseca RJ, Koutnik AW. Total subapical sub-osteotomy: a modification of the surgical technique. Int J Adult Orthodon Orthognath Surg 1986;1:119–28. 8. Eliades T, Hegdvedt AK, Larsen PE, Herpy AK. Treatment of Class II division 2 malocclusion with combined bilateral sagittal split osteotomy and total subapical osteotomy. Int J Adult Orthodon Orthognath Surg 1994;9:213–22.