LETTERS TO THE EDITOR

J Oral Maxillofac Surg66:1317-1322, 2008

ORTHODONTIC EXTRACTION: THE RISKLESSEXTRACTION OF THE IMPACTED LOWER THIRDMOLARS CLOSE TO THE MANDIBULAR CANAL

To the Editor:—I read with interest the article entitled“Orthodontic Extraction: Riskless Extraction of ImpactedThird Molars Close to the Mandibular Canal” in the Decem-ber 2007 issue of the Journal.1 It is indeed a universallyagreed and proven fact that extractions of deeply impactedlower third molars carry a considerable amount of risk tothe inferior alveolar nerve. While Bonetti et al have takenmuch effort to explain the rationale and techniques oforthodontic extraction at great length, I wonder why theyhave not considered alternative techniques to completeextraction. Coronectomy (partial odontectomy) appears tobe an effective replacement for “traditional removal” inhigh-risk cases. The studies by O’Riordan,2 Pogrel et al,3 andmore recently Renton et al4 have more or less establishedthe efficacy of coronectomy over complete removal. Hence,in view of the above findings, I wonder whether the use ofan orthodontic extraction for a high-risk impaction wouldbe like killing a sparrow with a missile!

P.N. RAMARAJ, MDS, FFDRCSI, MOMS RCPS GlasgSullia, Karnataka, India

References1. Bonetti GA, Bendandi M, Laino L, et al: Orthodontic extraction:

Riskless extraction of impacted lower third molars close to themandibular canal. J Oral Maxillofac Surg 65:2580, 2007

2. O’Riordan BC: Coronectomy (intentional partial odontectomy oflower third molar). Oral Surg Oral Med Oral Pathol Oral RadiolEndod 98:274, 2004

3. Pogrel MA, Lee JS, Muff DF: Coronectomy: A technique toprotect the inferior alveolar nerve. J Oral Maxillofac Surg 62:1447, 2004

4. Renton T, Hankins M, Sproate C, et al: A randomized controlledclinical trial to compare the incidence of injury to the inferioralveolar nerve as a result of coronectomy and removal of man-dibular third molar. Br J Oral Maxillofac Surg 43:7, 2005

doi:10.1016/j.joms.2008.02.008

In reply:—We thank Dr Ramaraj for his interest in ourarticle.1,2 The “orthodontic extraction” technique that weoutlined in the article would only represent an additionalchance to the surgeon for high-risk extraction of impactedmandibular third molars that are in a close anatomic relationwith the inferior alveolar nerve. It is clear that such anapproach cannot be used on a routine basis, as we men-tioned in the article. Each clinical case must be carefullyselected and evaluated.

The orthodontic extraction has proven to be a prudentand safe therapeutic choice, a biologically conservative ap-proach allowing the treatment of high-risk impaction withno risk of postoperative complications in more than 80patients. The same findings, including advantages on a peri-odontal level, were obtained by Hirsch et al.3

On the contrary, the coronectomy has a “high complica-tion rate of unsatisfactory healing” as mentioned in thearticle by O’Riordan.4 Furthermore, this approach may becomplicated by “inadvertent mobilization of the roots dur-ing decoronation of the tooth” and the fact that “retainedroots may cause a late infection or require removal,” asreported by Renton et al.5 For these reasons, Renton et alwrote that the coronectomy failed in 36 of 94 patients.

It is our opinion that coronectomy (partial odontectomy)cannot be considered “an effective replacement for ‘traditionalremoval’ in high-risk cases,” as stated by Dr Ramaraj,1 but itcould be an optimal solution in those cases of tooth ankylosiswhere the orthodontic extraction technique is ineffective.

We thank Dr Ramaraj for his comment and the Editor forthe chance for discussion.

GIULIO ALESSANDRI BONETTI, MD, DDSBologna, Italy

References1. Ramaraj PN: Orthodontic extraction: The riskless extraction of

the impacted lower third molars close to the mandibular canal.J Oral Maxillofac Surg 66:1317, 2008

2. Alessandri Bonetti G, Bendandi M, Laino L, et al: Orthodonticextraction: Riskless extraction of impacted lower third molars closeto the mandibular canal. J Oral Maxillofac Surg 65:2580, 2007

3. Hirsch A, Shteiman S, Boyan BD, et al: Use of orthodontictreatment as an aid to third molar extraction: A method forprevention of mandibular nerve injury and improved periodon-tal status. J Periodontol 74:887, 2003

4. O’Riordan BC: Coronectomy (intentional partial odontectomy oflower third molar). Oral Surg Oral Med Oral Pathol Oral RadiolEndod 98:274, 2004

5. Renton T, Hankins M, Sproate C, et al: A randomized controlledclinical trial to compare the incidence of injury to the inferioralveolar nerve as a result of coronectomy and removal of man-dibular third molar. Br J Oral Maxillofac Surg 43:7, 2005

doi:10.1016/j.joms.2008.02.010

ZYGOMATIC FRACTURE IN A DIVER:POSTOPERATIVE CONSIDERATIONS

To the Editor:—Fractures of the zygomatic complex andoften their treatment involve the paranasal sinuses. Pa-tients with these fractures are considered to be at in-

Letters to the Editor are considered for publication (subject to editing and abridgment), provided they are submitted in1 of 2 ways. If typewritten, they must be submitted in duplicate, signed by all authors, double-spaced, and should notexceed 40 typewritten lines of manuscript text (excluding references). You may also e-mail your Letters to the Editor toassaell@ohsu.edu. The same length limits apply. Letters should not duplicate similar material being submitted or publishedelsewhere. Letters responding to a recent Journal article must be received within 6 weeks of the article’s publication.Receipt of letters is not acknowledged and there is no guarantee that your letter will be published. We cannot provideprepublication proofs. Submitting the letter constitutes your permission for its publication in any current or subsequentissue or edition of the Journal, in any form or media, now known or hereafter developed.

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creased risk (up to 65%) of developing surgical emphy-sema.1 The fracture may cause a communication betweenthe paranasal sinuses and the soft tissues of the head andneck through a tear in the paranasal sinus lining that mayresult in subcutaneous empyhsema. Therefore, patientswith midfacial or zygomatic fractures are cautionedagainst blowing the nose or travelling by air for a certainperiod of time after the fracture. The study by Mahmoodet al2 showed most oral and maxillofacial surgeons ad-vised their patients to refrain from flying; however, thelength of this period varied significantly from 1 surgeonto another. In patients with zygomatic fractures, thereare case reports in the literature presenting orbital orsubcutaneous emphysema due to air travel; however,there is less data regarding zygomatic fractures and div-ing. In this letter, the follow-up of a diver with a tripodfracture of the zygoma is presented.

A 37-year-old professional male diver sustained a zygo-matic fracture during a traffic accident. He was sittingunrestrained in the back seat of the car during a collision.He was referred to the emergency department of anotherhospital where he was diagnosed with right-sided zygo-matic fracture and presented to us 4 days later. He com-plained of facial deformity, numbness in the right cheekarea, along with pain and tenderness on the bone. Therewere no visual complaints and no limitation in mouthopening. He was scheduled for an open reduction oper-ation on the seventh day after the accident. During sur-gery, the zygoma was exposed with subciliary, intraoral,and lateral brow incisions. The infraorbital nerve wastrapped between fracture fragments. Using a bone hook,the zygoma was reduced. The nerve was released. Theintegrity of the orbital floor was controlled. The infraor-bital rim was fixated first with microplates. The anteriorwall of the maxillary sinus had a comminuted fracture.The fractured pieces of lamellar bone and the laceratedmaxillary sinus mucosa were removed. A miniplate wasused to stabilize the zygomaticomaxillary buttress. Fi-nally, the zygomaticofrontal buttress was secured with aminiplate. The orbital floor and the accuracy of the re-duction were controlled, and no bone defect was seen.After completion of the fixation, a large bone defect onthe anterior maxillary wall still remained. One swingingfragment of maxillary bone that was attached to thezygoma laterally and measured approximately 2 cm � 1.5cm was secured to the plate using prolene sutures. Theremaining small fragments of bone were not replaced,considering that they would not be vascularized and

would fail to survive as free bone grafts. At the end of theoperation, an approximately 3 cm � 2 cm bone defectremained in the anterior maxillary wall (Fig 1). The skinand mucosa incisions were closed primarily. There wereno postoperative complications. The patient was advisedto refrain from diving, and on the third postoperativemonth, he was allowed to go into the hyperbaric cham-ber. The initial trial was at 10 meters for 30 minutes and wasgradually increased over the weeks. On the sixth postopera-tive month, he was allowed to dive in the sea. He did not faceany problems except for minimal swelling in the face afterdiving, which did not recur in subsequent dives.

Divers experience significant pressure changes within ashort period of time. During descent and ascent, the gasescontained in the divers’ body cavities such as lungs, ears,and sinuses suffer volume changes that have to be compen-sated for by the cavities.3 According to Boyle’s law, thevolume of a gas is inversely proportional to its pressure.4

During descent, the air in these cavities is compressedunder pressure and expands as the diver approaches thesurface. The paranasal sinuses are important air-filled cavi-ties that may be subject to injury during diving. The sinusostia must remain patent throughout a dive to equalizeambient pressure through the nose. Failure to equalizepressure during descent results in a relative vacuum in thesinus cavity and thus elicits mucosal congestion, edema,hemorrhagic bullas, and free blood. During ascent, theexpanding air blocked by nonpatent ostia may cause frac-ture of the sinus walls and thus cause subcutaneous ororbital emphysema.5 The primary concern in the patientpresented here was the residual bone defect after surgeryon the anterior aspect of the maxilla. The air that wascompressed after descent could have expanded during as-cent if the maxillary ostium was not patent. After waitingfor 3 months, the patient was allowed to go into the hyper-baric chamber. The maxillary ostium could have been visu-alized with endoscopic sinus surgery, but this would re-quire another visit to the operating room, and we preferredto make a trial in the hyperbaric chamber. The patient didnot face any air-related problems, either due to normalostium function or to adequate fibrosis of soft tissues on theanterior maxillary wall and healed orbital floor, or to all ofthese.

Data regarding adverse events that occur due to pressurechanges in zygomatic fractures are mostly related to airtravel. This is an expected fact when the number of peoplewho fly and dive are compared. We wanted to present thispatient to share our experience in the follow-up and toprovide anecdotal data on diving and maxillofacial sur-gery. We believe that waiting for 3 months before sub-jecting the patient to any pressure changes in the hyper-baric chamber allowed the orbital floor fracture to unite,and created enough fibrosis between the anterior maxil-lary wall and soft tissues of the cheek to prevent theescape of air in the possible presence of maxillary ostiumobstruction. An earlier dive could have been possible, butwhen possible risks are considered, being on on the safeside was our preference.

SERDAR TUNCER, MDORHAN CıZMECı, MD

Istanbul, Turkey

References1. Birrer RB, Robinson T, Papachristos P: Orbital emphysema: How

common, how significant? Ann Emerg Med 24:1115, 1994

FIGURE 1. Bone defect in the anterior maxillary wall (asterisk).

1318 LETTERS TO THE EDITOR

2. Mahmood S, Keith DJW, Lello GE: When can patients blow theirnose and fly after treatment for fractures of zygomatic complex:The need for a consensus. Injury 34:908, 2003

3. DeGorordo A, Vallejo-Manzur F, Chanin K, et al: Diving emer-gencies. Resuscitation 59:171, 2003

4. Klingmann C, Praetorius M, Baumann I, et al: Otorhinolaryngo-logic disorders and diving accidents: An analysis of 306 divers.Eur Arch Otorhinolaryngol 264:1243, 2007

5. Becker GD, Parell GJ: Barotrauma of the ears and sinuses afterscuba diving. Eur Arch Otorhinolaryngol 258:159, 2001

doi:10.1016/j.joms.2008.02.013

PAGET’S DISEASE AND BISPHOSPHONATE-ASSOCIATED OSTEONECROSIS OF THE JAWS

To the Editor:—Bisphosphonates are a well-known group ofdrugs that are useful for preventing bone metastasis.1 Thesedrugs are also used to treat Paget’s disease, both orally orintravenously. Although bisphosphonate-associated osteo-necrosis of the jaws (BON) has been observed, especially inoncology patients, only a few patients with Paget’s diseasedevelop this condition. Moreover, when such patients de-velop high-risk metastatic malignancies, additional bisphos-phonate doses are needed.

An 84-year-old man presented at Stomatology Unit–UFPEwith maxillary bone exposure that had evolved over 6months. He had already undergone a partial maxillectomy,including the anterior wall and floor of the left maxillarysinus. His medical history included Paget’s disease affectingthe maxilla and hip, treated with 1 infusion of pamidronate(90 mg) and 3 infusions of zolendronic acid (4 mg). He alsohad a history of nonsimultaneous gastric and prostate ma-lignancies, which caused hypercalcemia secondary to ma-lignancy. Both tumors were treated with surgery, togetherwith 8 infusions of zolendronic acid (4 mg) and 1 of pam-idronate (90 mg) to control malignant hypercalcemia. Oneyear after the last bisphosphonate infusion, the patientreported a spontaneous, slightly painful bone exposure inthe anterior left maxilla. On intraoral examination, grade IIBON was observed adjacent to the maxillary left canine andbetween the upper central incisors. There was no history oftrauma or dental extraction. He was treated with localdebridement and clindamycin (300 mg, 4 times daily), met-ronidazole (400 mg, 3 times daily), and chlorhexidine 0.12%oral rinses for 2 months. The local infection was con-trolled, although healing was only partial after 18months. Because no pain or discomfort was reported, heis being followed at regular intervals and still has anasymptomatic bone exposure.

Not surprisingly, less than 5% of BON cases occur innoncancer patients, which can be classified as a low-riskgroup.2 Osteonecrosis is directly related to the duration ofbisphosphonate therapy and usually occurs after severalmonths of zolendronic acid treatment or a few years ofpamidronate treatment. Generally, patients who receiveless than 12 cycles of intravenous bisphosphonates rarelydevelop this complication.3 Our patient received 11 cyclesof zolendronic acid and 2 cycles of pamidronate, whichwould be considered an uncommon dose for spontaneousnecrotic bone exposure. Interestingly, the largest well-structured trials that analyzed the efficacy of oral and intra-venous bisphosphonate in both Paget’s disease and osteo-porosis failed to report any cases of BON.4,5 A single dose of5 mg of zolendronic acid is even more effective than rised-ronate treatment (30 mg/day for 2 months), giving adequatedisease control for 6 months.5,6 Therefore, because 1 or 2

doses of zolendronic acid annually are adequate for con-trolling Paget’s disease, a high incidence of BON shouldnot be expected in this patient group following long-termtreatment.

Nevertheless, some features of Paget’s disease might in-crease the risk of BON. Some Paget’s patients developspontaneous pathologic fractures and oral osteonecrosis,regardless of treatment, and this also increases the likeli-hood of developing BON.7,8 However, such episodes arerare and should not be considered a remarkable risk factor.

In summary, long-term intravenous bisphosphonate treat-ment for Paget’s disease increases the likelihood of devel-oping BON, especially when associated with additionaldoses for managing neoplastic disease. Regular oral exami-nations are important for establishing an early diagnosis andadequate treatment.

Acknowledgment

The authors were supported by The National Council for Scien-tific and Technological Development (CNPq) and The State of SaoPaulo Research Foundation (FAPESP). The authors declare no con-flict of interest.

LUIZ ALCINO GUEIROS, DDSMÁRCIO AJUDARTE LOPES, DDS, PHD

Piracicaba, Brazil

JAIR CARNEIRO LEÃO, DDS, PHDRecife, Brazil

References1. Bossier S, Magnetto S, Frappart L, et al: Bisphosphonates inhibit

prostate and breast carcinoma cell adhesion to unmineralizedand mineralized bone extracellular matrices. Cancer Res 57:3890, 1997

2. Shane E, Goldring S, Christakos S, et al: Osteonecrosis of thejaws: More research needed. J Bone Miner Res 21:1503, 2006

3. Bamias A, Kastritis E, Bamia C, et al: Osteonecrosis of the jaw incancer after treatment with bisphosphonates: Incidence and riskfactors. J Clin Oncol 23:8580, 2005

4. Bone HG, Hosking D, Devogelaer JP, et al: Ten years’ experiencewith alendronate for osteoporosis in postmenopausal women.N Engl J Med 350:1189, 2004

5. Hosking D: Pharmacological therapy of Paget=s and other meta-bolic bone diseases. Bone 38:S3, 2006

6. Reid IR, Miller P, Lyles K, et al: Comparison of zolendronic acidwith risdedronate for Paget’s disease. N Engl J Med 353:898,2005

7. McMahon P, Tzadik A: Paget’s disease of the bone presenting asan apparent oral antral fistula. Arch Otolaryngol Head Neck Surg112:668, 1986

8. Thomas DW, Tate RJ, Shepherd JP: Mandibular deformity asso-ciated with Paget’s disease: Case report. Aust Dent J 39:162,1994

doi:10.1016/j.joms.2008.02.011

SERUM CTX TESTING

To the Editor:—I am concerned that the report by Marx etal on osteonecrosis of the jaw associated with the use oforal bisphosphonates (in the December 2007 issue of theJournal of Oral and Maxillofacial Surgery; J Oral Maxillo-fac Surg 65:2397, 2007) may be misinterpreted by the read-ership. Both the lead position of the article in the researchsection of the Journal and the prominence of its authorshave led some of my colleagues to remark that a gold

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