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Incidence and Consequences of Bur Breakage in Orthognathic Surgery: A Retrospective Study With Discussion of 2 Interesting Clinical Situations
J Oral Maxillofac Surg 69:2442-2447, 2011
Incidence and Consequences of Bur Breakage in Orthognathic Surgery: A Retrospective Study With Discussion of 2 Interesting Clinical Situations Ramanathan Manikandhan, MDS, FDSRCS, FFDRCS,* Parameswaran Anantanarayanan, MDS, DNB, MNAMS,† Pynamoottil Cherian Mathew, MDS,‡ Jayakumar Naveen Kumar, MDS,§ and Vivek Narayanan, MDS储 Purpose: To determine the incidence of bur breakage in routine orthognathic surgery, as well as its
postsurgical sequela, and to illustrate 2 cases with more than 6 months’ follow-up. Patients and Methods: We performed a retrospective evaluation of case records of 76 consecutive orthognathic surgical procedures performed by a team of 2 surgeons over a period of 16 months, between January 2009 and July 2010, at a single center. Results: Surgical bur breakage was reported in 5 patients in the series. Of these, 3 were retrieved whereas 2 were not, 1 of which caused a foreign body reaction in the patient, which persisted for a duration of almost 1 year. Conclusion: Instrument breakage may be a relatively common occurrence with the use of surgical burs in orthognathic surgery but its incidence is seldom recorded or reported. This study gives insight into the probability of postoperative sequela of these instruments when left in situ and a protocol for management of broken instruments. © 2011 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 69:2442-2447, 2011 Broken instruments (surgical burs and drill bits) are reported complications in orthognathic literature but have seldom been discussed in detail to provide any clarity as to their fate.1 The literature shows practically no details in any published material on the inci*Director, Cleft & Craniofacial Unit, Meenakshiammal Dental College & Hospital, Maduravoyal, India. †Professor, Meenakshiammal Dental College & Hospital, Maduravoyal, India. ‡Senior Lecturer, Meenakshiammal Dental College & Hospital, Maduravoyal, India. §Reader, Meenakshiammal Dental College & Hospital, Maduravoyal, India. 储Professor, Raja Mutiah Dental College & Hospital, Annamalainagar, India. Address correspondence and reprint requests to Dr Anantanarayanan: AF 39, 6th St, 11th Main Rd, Annanagar, Chennai 600040, India; e-mail: [email protected] © 2011 American Association of Oral and Maxillofacial Surgeons
0278-2391/11/6909-0030$36.00/0 doi:10.1016/j.joms.2010.12.047
dence or sequela of broken instruments during routine orthognathic procedures.2-4 There is ample available literature on the reaction of tissues to mini-plates in the maxillofacial region and their biocompatibility, but these data cannot be used to standardize the management of drill and bur breakage.5-7 The presentation of a case of foreign body reaction due to a broken bur left in situ at our institute made us search for relevant literature, the absence of which prompted us to retrospectively evaluate our case records in this context to determine the frequency of instrument breakage and its postsurgical outcome.
Patients and Methods Seventy-six patients who underwent routine orthognathic surgery in our center between January 2009 and July 2010 were selected (Table 1). Their case records were obtained and evaluated retrospectively for intraoperative events in the form of any instrument breakage during the osteotomy or internal fixation. The occurrence of instrument breakage, the
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MANIKANDHAN ET AL
Table 1. DETAILS OF PROCEDURES PERFORMED AND NUMBER OF PATIENTS OPERATED UPON
No. of Patients Osteotomy procedure Le Fort I BSSO BSSO ⫹ genioplasty Le Fort I ⫹ BSSO Le Fort I ⫹ genioplasty Le Fort I ⫹ AMO Total
14 17 6 28 8 3 76
Abbreviations: BSSO, bilateral sagittal split osteotomy; AMO, anterior maxillary osteotomy. Manikandhan et al. Incidence and Consequences of Bur Breakage. J Oral Maxillofac Surg 2011.
retrieval process, and the postsurgical outcome were evaluated for a minimum period of 5 months. All patients underwent osteotomies with a Stryker TPS surgical console and surgical drill (Stryker, Kalamazoo, MI). The surgical burs used were SS White tungsten carbide burs (Nos. 701 and 702; SS White Burs, Lakewood, NJ).
Results Of the 76 procedures evaluated, 5 had surgical bur breakage during the osteotomy, 1 in the maxilla and 4 in the mandible. Three of the broken bur heads were retrieved intraoperatively, whereas 2 were not retrieved. Both of the latter patients underwent postoperative radiography, which confirmed the presence of an impregnated bur head within the bony substance.
PATIENT 1
An 18-year-old trisomy patient presented with Class III mandibular prognathism for surgical correction after presurgical orthodontic treatment. The patient was otherwise medically fit and underwent a bilateral sagittal split osteotomy under general anesthesia. The operation was uneventful apart from the fact that a No. 702 surgical bur broke during the completion of the lower border cut in the vertical limb of the bilateral sagittal split osteotomy on the right side. A search for the bur at that point was futile, and the osteotomy fixation was performed by miniplate osteosynthesis. The postoperative panoramic radiograph showed the missing bur head impregnated in the lower border. The patient returned after 3 months with an infection in the region of fixation on the same side as the broken bur. The miniplates were removed because they were identified to be the source of infection, whereas no retrieval of the broken bur head was attempted because no infection or radiographic bone density changes were present around it. One year later, the patient returned for a third time because there was a swelling (3 ⫻ 2 cm) in the lower right submandibular area with tenderness around the jaw with no secondary changes such as sinus tract or discharge present (Fig 1). The swelling was present on the side of the broken bur, and panoramic radiograph showed an intense halo of radiolucent area (1.5 ⫻ 1 cm in size) in the lower border of the mandible around the bur head (Fig 2). A diagnosis of foreign body reaction was made, and patient underwent a third surgery for the removal
FIGURE 1. Clinical photograph of patient 1 showing a swelling in right submandibular region. Manikandhan et al. Incidence and Consequences of Bur Breakage. J Oral Maxillofac Surg 2011.
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INCIDENCE AND CONSEQUENCES OF BUR BREAKAGE
FIGURE 2. Panoramic radiograph obtained at 15 months postoperatively, showing presence of intense radiolucency surrounding impregnated bur head. Manikandhan et al. Incidence and Consequences of Bur Breakage. J Oral Maxillofac Surg 2011.
of foreign body granuloma and the broken bur (Fig 3). Follow-up at 5 months after retrieval showed complete resolution of all symptoms. CASE 2
A 23-year-old man presented with a skeletal Class III problem, and surgical correction was planned after presurgical orthodontic preparation. The patient was prepared for general anesthesia and was free of any medical complaints. He underwent a bimaxillary procedure with a Le Fort I advancement and a bilateral sagittal split osteotomy for setback under general anesthesia. During the Le Fort I osteotomy, there was an inadvertent separation of the surgical bur head from the shank. A thorough search was performed, and the procedure was resumed without retrieval of the broken instrument. The procedure was otherwise uneventful, and the patient was discharged on the third postoperative day with routine postoperative instructions. The postoperative panoramic radiograph and lateral cephalogram showed the implantation of the broken bur in the retro-tuberosity region of the maxilla on the right side (Figs 4, 5). The patient has been followed up for 11 months without any undesirable consequence.
Discussion Instrument breakage during orthognathic surgery may not be a common complication reported.1-4 The reason for this may be the nature of instrumentation used at different centers. The use of surgical saws and peizoelectric saws in most developed nations for orthognathic surgery may have reduced this incidence significantly. The use of surgical drills and burs still remains the gold standard in most developing nations and countries in transition. This may be a reason for the increased incidence of instrument breakage in our center, where the ease of operation and habituation makes us choose the surgical drill over the saw for most of our procedures. Five instrument breakages were recorded in our series, but were seldom taken seriously. If the retrieval process failed, the bur was left in-situ categorized as a sterile implant, which may not produce any undesirable consequence. The reason for this may also be attributed to the minimal or practically nonexistent dental or maxillofacial literature in this accord.1,8 The most significant reasons for instrument breakage may be attributed to:
MANIKANDHAN ET AL
FIGURE 3. Retrieved bur head impregnated in bone and surrounded by granulomatous tissue. Manikandhan et al. Incidence and Consequences of Bur Breakage. J Oral Maxillofac Surg 2011.
FIGURE 4. Panoramic radiograph of patient 2, showing broken bur head in posterior maxillary region (arrow). Manikandhan et al. Incidence and Consequences of Bur Breakage. J Oral Maxillofac Surg 2011.
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INCIDENCE AND CONSEQUENCES OF BUR BREAKAGE
FIGURE 5. Lateral cephalogram of patient 2 showing broken bur head (arrow). Manikandhan et al. Incidence and Consequences of Bur Breakage. J Oral Maxillofac Surg 2011.
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MANIKANDHAN ET AL
1. The reuse of instruments and repeated sterilization cycles8,9 2. Surgery performed by junior consultants, where inexperience may play a role.10 In our series the predilection for bur breakage was more in favor of the mandible than the maxilla— 4 out of 5 times. This may be attributed to the dense cortical bone in the mandible. The most frequent site of breakage in the mandible was the lower border, and the isolated occurrence in the maxilla was at the retro-tuberosity region, which is a load-bearing buttress and is again formed of dense cortical bone. The present literature, though documenting instrument breakage as a complication in orthognathic surgery, does not reveal any incidence or post– event management sequence in detail. A retrospective evaluation of our case records for a period of 16 months yielded an incidence of 7% with the use of surgical burs as a means to perform osteotomies. Orthopedic literature reports instrument breakage as an important complication in bone surgery; the need for retrieval is governed only by the presence of the drills in contact with implants in situ, and a broken instrument may be removed only when it can be achieved easily or in conjunction with implant removal.8-12 Moreover, in some cases an attempted removal of the broken instrument may cause injury to vital structures including the inferior alveolar nerve and roots of the teeth. An attempted retrieval may also increase the bur hole size and loss of good surrounding bone, creating difficulty in locating sites for osteosynthesis. At this juncture, a protocol for the management of broken drills may be suggested: 1. The procedure is stopped temporarily, and the position of the broken instrument (bur/drill) is located. 2. Once located, the instrument is retrieved manually if visible. 3. The oropharyngeal region and the operating site are thoroughly checked. 4. If not visualized, the surgical waste and suction are silted and searched manually. 5. The occurrence of the event is documented in the case record. 6. The patient undergoes a radiographic evaluation of the surgical site postoperatively to evaluate
intraosseous impregnation of the instrument or migration with documentation and is informed about the intraoperative event. 7. The patient is sequentially evaluated monthly, and radiographs are taken at 3-month intervals. The exaggerated tissue response for one of the patients in our series may be attributed to a foreign body reaction, which is rare. Studies indicate that a mild tissue reaction is elicited in the body to various implants placed inside the body in the peri-implant region with a small infiltration of immunocompetent cells.5-7 In a normal event, a non-retrievable instrument may be considered inert and left in situ and a second procedure to retrieve the instrument may not be warranted. However, a serial review of the patient clinically and radiographically for at least 1 year is mandated.
References 1. Kim S, Park S: Incidence of complications and problems related to orthognathic surgery. J Oral Maxillofac Surg 65:2438, 2007 2. Acebal-Bianc F, Vuylsteke PLPJ, Mommaerts MY, et al: Perioperative complications in corrective facial orthopedic surgery: A 5-year retrospective study. J Oral Maxillofac Surg 58:754, 2000 3. Panula K, Finne K, Oikarinen K: Incidence of complications and problems related to orthognathic surgery: A review of 655 patients. J Oral Maxillofac Surg 59:1128, 2001 4. Chow LK, Singh B, Chiu WK, et al: Prevalence of postoperative complications after orthognathic surgery: A 15-year review. J Oral Maxillofac Surg 65:984, 2007 5. Torgersen S, Gjerdet NR, Erichsen ES, et al: Metal particles and tissue changes adjacent to miniplates. A retrieval study. Acta Odontol Scand 53:65, 1995 6. Torgersen S, Moe G, Jonsson R: Immunocompetent cells adjacent to stainless steel and titanium miniplates and screws. Eur J Oral Sci 103:46, 1995 7. Torgersen S, Gilhuus-Moe OT, Gjerdet NR: Immune response to nickel and some clinical observations after stainless steel miniplate osteosynthesis. Int J Oral Maxillofac Surg 22:246, 1993 8. Bodner L, Woldenberg Y, Puterman M: Drill failure during ORIF of the mandible. Complication management. Med Oral Patol Oral Cir Bucal 1:E591, 2007 9. Ashford RU, Pande KC, Dey A: Current practice regarding re-use of trauma instrumentation: Results of a postal questionnaire survey. Injury 32:37, 2001 10. Price MV, Molloy S, Solan MC, et al: The rate of instrument breakage during orthopaedic procedures. Int Orthop 26:185, 2002 11. Pichler W, Mazzurana P, Clement H, et al: Frequency of instrument breakage during orthopaedic procedures and its effects on patients. J Bone Joint Surg Am 90:2652, 2008 12. Hirt U, Auer JA, Perren SM: Drill bit failure without implant involvement—An intraoperative complication in orthopaedic surgery. Injury 23:S5, 1992 (suppl 2)
Incidence and Consequences of Bur Breakage in Orthognathic Surgery: A Retrospective Study With Discussion of 2 Interesting Clinical Situations Ramanathan Manikandhan, MDS, FDSRCS, FFDRCS,* Parameswaran Anantanarayanan, MDS, DNB, MNAMS,† Pynamoottil Cherian Mathew, MDS,‡ Jayakumar Naveen Kumar, MDS,§ and Vivek Narayanan, MDS储 Purpose: To determine the incidence of bur breakage in routine orthognathic surgery, as well as its
postsurgical sequela, and to illustrate 2 cases with more than 6 months’ follow-up. Patients and Methods: We performed a retrospective evaluation of case records of 76 consecutive orthognathic surgical procedures performed by a team of 2 surgeons over a period of 16 months, between January 2009 and July 2010, at a single center. Results: Surgical bur breakage was reported in 5 patients in the series. Of these, 3 were retrieved whereas 2 were not, 1 of which caused a foreign body reaction in the patient, which persisted for a duration of almost 1 year. Conclusion: Instrument breakage may be a relatively common occurrence with the use of surgical burs in orthognathic surgery but its incidence is seldom recorded or reported. This study gives insight into the probability of postoperative sequela of these instruments when left in situ and a protocol for management of broken instruments. © 2011 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 69:2442-2447, 2011 Broken instruments (surgical burs and drill bits) are reported complications in orthognathic literature but have seldom been discussed in detail to provide any clarity as to their fate.1 The literature shows practically no details in any published material on the inci*Director, Cleft & Craniofacial Unit, Meenakshiammal Dental College & Hospital, Maduravoyal, India. †Professor, Meenakshiammal Dental College & Hospital, Maduravoyal, India. ‡Senior Lecturer, Meenakshiammal Dental College & Hospital, Maduravoyal, India. §Reader, Meenakshiammal Dental College & Hospital, Maduravoyal, India. 储Professor, Raja Mutiah Dental College & Hospital, Annamalainagar, India. Address correspondence and reprint requests to Dr Anantanarayanan: AF 39, 6th St, 11th Main Rd, Annanagar, Chennai 600040, India; e-mail: [email protected] © 2011 American Association of Oral and Maxillofacial Surgeons
0278-2391/11/6909-0030$36.00/0 doi:10.1016/j.joms.2010.12.047
dence or sequela of broken instruments during routine orthognathic procedures.2-4 There is ample available literature on the reaction of tissues to mini-plates in the maxillofacial region and their biocompatibility, but these data cannot be used to standardize the management of drill and bur breakage.5-7 The presentation of a case of foreign body reaction due to a broken bur left in situ at our institute made us search for relevant literature, the absence of which prompted us to retrospectively evaluate our case records in this context to determine the frequency of instrument breakage and its postsurgical outcome.
Patients and Methods Seventy-six patients who underwent routine orthognathic surgery in our center between January 2009 and July 2010 were selected (Table 1). Their case records were obtained and evaluated retrospectively for intraoperative events in the form of any instrument breakage during the osteotomy or internal fixation. The occurrence of instrument breakage, the
2442
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MANIKANDHAN ET AL
Table 1. DETAILS OF PROCEDURES PERFORMED AND NUMBER OF PATIENTS OPERATED UPON
No. of Patients Osteotomy procedure Le Fort I BSSO BSSO ⫹ genioplasty Le Fort I ⫹ BSSO Le Fort I ⫹ genioplasty Le Fort I ⫹ AMO Total
14 17 6 28 8 3 76
Abbreviations: BSSO, bilateral sagittal split osteotomy; AMO, anterior maxillary osteotomy. Manikandhan et al. Incidence and Consequences of Bur Breakage. J Oral Maxillofac Surg 2011.
retrieval process, and the postsurgical outcome were evaluated for a minimum period of 5 months. All patients underwent osteotomies with a Stryker TPS surgical console and surgical drill (Stryker, Kalamazoo, MI). The surgical burs used were SS White tungsten carbide burs (Nos. 701 and 702; SS White Burs, Lakewood, NJ).
Results Of the 76 procedures evaluated, 5 had surgical bur breakage during the osteotomy, 1 in the maxilla and 4 in the mandible. Three of the broken bur heads were retrieved intraoperatively, whereas 2 were not retrieved. Both of the latter patients underwent postoperative radiography, which confirmed the presence of an impregnated bur head within the bony substance.
PATIENT 1
An 18-year-old trisomy patient presented with Class III mandibular prognathism for surgical correction after presurgical orthodontic treatment. The patient was otherwise medically fit and underwent a bilateral sagittal split osteotomy under general anesthesia. The operation was uneventful apart from the fact that a No. 702 surgical bur broke during the completion of the lower border cut in the vertical limb of the bilateral sagittal split osteotomy on the right side. A search for the bur at that point was futile, and the osteotomy fixation was performed by miniplate osteosynthesis. The postoperative panoramic radiograph showed the missing bur head impregnated in the lower border. The patient returned after 3 months with an infection in the region of fixation on the same side as the broken bur. The miniplates were removed because they were identified to be the source of infection, whereas no retrieval of the broken bur head was attempted because no infection or radiographic bone density changes were present around it. One year later, the patient returned for a third time because there was a swelling (3 ⫻ 2 cm) in the lower right submandibular area with tenderness around the jaw with no secondary changes such as sinus tract or discharge present (Fig 1). The swelling was present on the side of the broken bur, and panoramic radiograph showed an intense halo of radiolucent area (1.5 ⫻ 1 cm in size) in the lower border of the mandible around the bur head (Fig 2). A diagnosis of foreign body reaction was made, and patient underwent a third surgery for the removal
FIGURE 1. Clinical photograph of patient 1 showing a swelling in right submandibular region. Manikandhan et al. Incidence and Consequences of Bur Breakage. J Oral Maxillofac Surg 2011.
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INCIDENCE AND CONSEQUENCES OF BUR BREAKAGE
FIGURE 2. Panoramic radiograph obtained at 15 months postoperatively, showing presence of intense radiolucency surrounding impregnated bur head. Manikandhan et al. Incidence and Consequences of Bur Breakage. J Oral Maxillofac Surg 2011.
of foreign body granuloma and the broken bur (Fig 3). Follow-up at 5 months after retrieval showed complete resolution of all symptoms. CASE 2
A 23-year-old man presented with a skeletal Class III problem, and surgical correction was planned after presurgical orthodontic preparation. The patient was prepared for general anesthesia and was free of any medical complaints. He underwent a bimaxillary procedure with a Le Fort I advancement and a bilateral sagittal split osteotomy for setback under general anesthesia. During the Le Fort I osteotomy, there was an inadvertent separation of the surgical bur head from the shank. A thorough search was performed, and the procedure was resumed without retrieval of the broken instrument. The procedure was otherwise uneventful, and the patient was discharged on the third postoperative day with routine postoperative instructions. The postoperative panoramic radiograph and lateral cephalogram showed the implantation of the broken bur in the retro-tuberosity region of the maxilla on the right side (Figs 4, 5). The patient has been followed up for 11 months without any undesirable consequence.
Discussion Instrument breakage during orthognathic surgery may not be a common complication reported.1-4 The reason for this may be the nature of instrumentation used at different centers. The use of surgical saws and peizoelectric saws in most developed nations for orthognathic surgery may have reduced this incidence significantly. The use of surgical drills and burs still remains the gold standard in most developing nations and countries in transition. This may be a reason for the increased incidence of instrument breakage in our center, where the ease of operation and habituation makes us choose the surgical drill over the saw for most of our procedures. Five instrument breakages were recorded in our series, but were seldom taken seriously. If the retrieval process failed, the bur was left in-situ categorized as a sterile implant, which may not produce any undesirable consequence. The reason for this may also be attributed to the minimal or practically nonexistent dental or maxillofacial literature in this accord.1,8 The most significant reasons for instrument breakage may be attributed to:
MANIKANDHAN ET AL
FIGURE 3. Retrieved bur head impregnated in bone and surrounded by granulomatous tissue. Manikandhan et al. Incidence and Consequences of Bur Breakage. J Oral Maxillofac Surg 2011.
FIGURE 4. Panoramic radiograph of patient 2, showing broken bur head in posterior maxillary region (arrow). Manikandhan et al. Incidence and Consequences of Bur Breakage. J Oral Maxillofac Surg 2011.
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INCIDENCE AND CONSEQUENCES OF BUR BREAKAGE
FIGURE 5. Lateral cephalogram of patient 2 showing broken bur head (arrow). Manikandhan et al. Incidence and Consequences of Bur Breakage. J Oral Maxillofac Surg 2011.
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MANIKANDHAN ET AL
1. The reuse of instruments and repeated sterilization cycles8,9 2. Surgery performed by junior consultants, where inexperience may play a role.10 In our series the predilection for bur breakage was more in favor of the mandible than the maxilla— 4 out of 5 times. This may be attributed to the dense cortical bone in the mandible. The most frequent site of breakage in the mandible was the lower border, and the isolated occurrence in the maxilla was at the retro-tuberosity region, which is a load-bearing buttress and is again formed of dense cortical bone. The present literature, though documenting instrument breakage as a complication in orthognathic surgery, does not reveal any incidence or post– event management sequence in detail. A retrospective evaluation of our case records for a period of 16 months yielded an incidence of 7% with the use of surgical burs as a means to perform osteotomies. Orthopedic literature reports instrument breakage as an important complication in bone surgery; the need for retrieval is governed only by the presence of the drills in contact with implants in situ, and a broken instrument may be removed only when it can be achieved easily or in conjunction with implant removal.8-12 Moreover, in some cases an attempted removal of the broken instrument may cause injury to vital structures including the inferior alveolar nerve and roots of the teeth. An attempted retrieval may also increase the bur hole size and loss of good surrounding bone, creating difficulty in locating sites for osteosynthesis. At this juncture, a protocol for the management of broken drills may be suggested: 1. The procedure is stopped temporarily, and the position of the broken instrument (bur/drill) is located. 2. Once located, the instrument is retrieved manually if visible. 3. The oropharyngeal region and the operating site are thoroughly checked. 4. If not visualized, the surgical waste and suction are silted and searched manually. 5. The occurrence of the event is documented in the case record. 6. The patient undergoes a radiographic evaluation of the surgical site postoperatively to evaluate
intraosseous impregnation of the instrument or migration with documentation and is informed about the intraoperative event. 7. The patient is sequentially evaluated monthly, and radiographs are taken at 3-month intervals. The exaggerated tissue response for one of the patients in our series may be attributed to a foreign body reaction, which is rare. Studies indicate that a mild tissue reaction is elicited in the body to various implants placed inside the body in the peri-implant region with a small infiltration of immunocompetent cells.5-7 In a normal event, a non-retrievable instrument may be considered inert and left in situ and a second procedure to retrieve the instrument may not be warranted. However, a serial review of the patient clinically and radiographically for at least 1 year is mandated.
References 1. Kim S, Park S: Incidence of complications and problems related to orthognathic surgery. J Oral Maxillofac Surg 65:2438, 2007 2. Acebal-Bianc F, Vuylsteke PLPJ, Mommaerts MY, et al: Perioperative complications in corrective facial orthopedic surgery: A 5-year retrospective study. J Oral Maxillofac Surg 58:754, 2000 3. Panula K, Finne K, Oikarinen K: Incidence of complications and problems related to orthognathic surgery: A review of 655 patients. J Oral Maxillofac Surg 59:1128, 2001 4. Chow LK, Singh B, Chiu WK, et al: Prevalence of postoperative complications after orthognathic surgery: A 15-year review. J Oral Maxillofac Surg 65:984, 2007 5. Torgersen S, Gjerdet NR, Erichsen ES, et al: Metal particles and tissue changes adjacent to miniplates. A retrieval study. Acta Odontol Scand 53:65, 1995 6. Torgersen S, Moe G, Jonsson R: Immunocompetent cells adjacent to stainless steel and titanium miniplates and screws. Eur J Oral Sci 103:46, 1995 7. Torgersen S, Gilhuus-Moe OT, Gjerdet NR: Immune response to nickel and some clinical observations after stainless steel miniplate osteosynthesis. Int J Oral Maxillofac Surg 22:246, 1993 8. Bodner L, Woldenberg Y, Puterman M: Drill failure during ORIF of the mandible. Complication management. Med Oral Patol Oral Cir Bucal 1:E591, 2007 9. Ashford RU, Pande KC, Dey A: Current practice regarding re-use of trauma instrumentation: Results of a postal questionnaire survey. Injury 32:37, 2001 10. Price MV, Molloy S, Solan MC, et al: The rate of instrument breakage during orthopaedic procedures. Int Orthop 26:185, 2002 11. Pichler W, Mazzurana P, Clement H, et al: Frequency of instrument breakage during orthopaedic procedures and its effects on patients. J Bone Joint Surg Am 90:2652, 2008 12. Hirt U, Auer JA, Perren SM: Drill bit failure without implant involvement—An intraoperative complication in orthopaedic surgery. Injury 23:S5, 1992 (suppl 2)