A. Cheng

Protocol in managing oral surgical patients taking dabigatran

New anticoagulants are being introduced into the market. These drugs are orally administered, have predictable pharmacokinetics and dose response, do not require monitoring and have an acceptable safety profile when used appropriately, and so avoid many of the disadvantages and possible complications of warfarin and heparin. Dabigatran is the most widely used, and has been approved by the Therapeutic Goods Administration. The use of dabigatran will likely increase in the coming years, and so it is important for dentists to be aware of its mechanism of action, the possible complications, and how to reverse the bleeding if it occurs. This review discusses dabigatran and reports on our experience of five cases, and provides practical clinical advice on how to manage patients on dabigatran who require dental treatment, particularly extractions.

A randomized controlled trial of superior and inferior temporomandibular joint space injection with hyaluronic acid in treatment of anterior disc displacement without reduction

PURPOSE To compare the outcome of inferior and superior joint space injection of sodium hyaluronate in patients with disc displacement without reduction of the temporomandibular joint (TMJ). MATERIALS AND METHODS One hundred twenty patients with disc displacement without reduction of TMJ were randomized into 2 experimental groups. One group of patients received superior joint space injections of sodium hyaluronate and the other group was treated with inferior joint space injections. Patients TMJ status and clinical symptoms were evaluated at the 3 and 6 month follow-up appointments. The clinical parameters recorded were maximal mouth opening (MMO), pain intensity on a visual analog scale (VAS), and modified Helkimos clinical dysfunction index and analyzed with ANCOVA. RESULTS Fifty of the superior and 54 of the inferior joint space injection therapy group returned for the 3 and 6 month evaluations; 86.67% of the patients were retained in the follow-up. MMO, VAS, and Helkimos index of both groups improved at the 3 and 6 month follow-ups. The results of MMO changes and TMJ function were almost the same in both groups at 3 month follow-up. However, there was a significant reduction in TMJ pain in the inferior joint injection group at 3 month follow-up compared with the superior joint injection group (P< .001). There were also significant differences between the inferior joint injection group and superior joint injection group in MMO (P< .005), VAS (P< .001), and Helkimos index (P< .001) at 6 month follow-up. CONCLUSION This study showed that inferior joint space injection with sodium hyaluronate is a valid method of treating disc displacement without reduction of TMJ and a long-term study will be needed to assess the effect of inferior joint injection on the morphologic changes of the TMJ.

Alveolar bone and the bisphosphonates

Bisphosphonate associated osteonecrosis of the jaws (ONJ) usually commences at the alveolus. Comparison is made between the structure and function of long bones and alveolar bone and the differing susceptibilities of the bisphosphonates at these different sites are explored. Current concepts of the causation of ONJ are discussed. The clinical implications of these findings to dentists managing periodontal conditions are presented.

Modified trans-oral approach for mandibular condylectomy.

Different approaches to the mandibular condyle have been described. In this paper, a modified trans-oral technique to access the mandibular condyle is described and illustrated. This technique was used in a small group of patients; the clinical outcomes are promising. The technique can be used in various temporomandibular joint (TMJ) operations, such as condylar resection, high condylectomy or tumor removal. It provides adequate intra-oral surgical access to the mandibular condyle and avoids complications from extra-oral approaches to the TMJ.

A C-Terminal Crosslinking Telopeptide Test–Based Protocol for Patients on Oral Bisphosphonates Requiring Extraction: A Prospective Single-Center Controlled Study

PURPOSE Patients undergoing extraction are at risk for bisphosphonate-related osteonecrosis of the jaws (BRONJ). A C-terminal crosslinking telopeptide (CTX) level lower than 150 pg/mL has been suggested as a predictor of BRONJ risk. The authors aimed to increase the precision of estimates of the risk of BRONJ in osteoporosis after extraction and to assess value of CTX testing at extraction time in cases of BRONJ in a large prospective cohort. PATIENTS AND METHODS All patients on oral bisphosphonates for osteoporosis referred for extractions over a period of 6.5 years were included in a standard protocol. Pre-extraction fasted CTX levels were obtained. All patients were followed until healing. If the CTX level was lower than 150 pg/mL, they were offered a drug holiday. If they declined, if the CTX level was above 150 pg/mL at baseline, or after the drug holiday, they had extractions performed under local anesthesia. Age-matched controls not on bisphosphonates were identified. RESULTS Nine hundred fifty patients had 2,461 extractions. One hundred eighty-one patients had a CTX level lower than 150 pg/mL. Four patients developed BRONJ; all had a CTX level lower than 150 pg/mL. All were on alendronate. The case-control comparison approached significance (<150 pg/mL; P = .073). Alendronate was associated with a low CTX level (P < .05). A CTX level lower than 150 pg/mL had a sensitivity of 100% and specificity of 81%. Bayesian analysis yielded a population expected risk of BRONJ of 0.29% (95% confidence interval, 0.12-0.52); the expected risk was 0.42% for a CTX level lower than 150 pg/mL and 0.13% for a CTX level higher than 150 pg/mL. CONCLUSION The risk of BRONJ for patients with osteoporosis on bisphosphonates having extractions is approximately 0.2%. A CTX level lower than 150 pg/mL is sensitive and is associated with an approximately 3-fold greater risk of BRONJ.

Navigation-Assisted Mandibular Body Distraction Osteogenesis: A Preliminary Study in Goats

PURPOSE The purpose of the present study was to evaluate the accuracy of navigation-assisted distraction osteogenesis of the mandible in a goat model. MATERIALS AND METHODS Six adult goats were included in the present study. A 3-dimensional (3D) image was reconstructed by performing computed tomography (CT) scans in 0.625-mm slices after placement of 5 maxillary marking screws and intermaxillary fixation with a prefabricated occlusal splint using the TBNavis-CMFS navigation system (Multifunctional Surgical Navigation System, Shanghai, China). Simulation distraction was performed to lengthen a unilateral mandibular body by 10 mm. Image-guided distraction osteogenesis was performed on the goat hemimandibles according to the preoperative planning. 3D skeletal measurements from the simulation were compared with those taken from the CT scans at 3 months postoperatively. RESULTS Navigation-assisted distraction osteogenesis was successfully performed in all 6 goat hemimandibles. The accuracy of the intraoperative registration was within 1 mm. The hemimandible was lengthened a mean of 10.02 mm (range 9.89 to 10.12). No significant differences were found between the simulation distraction and postoperative 3D measurements (P > .05). CONCLUSIONS Navigation-assisted distraction osteogenesis of the mandible in the goat model can be performed with high accuracy using the TBNavis-CMFS navigation system.

Customized bifocal and trifocal transport distraction osteogenesis device for extensive mandibular reconstruction.

Purpose: The objective of this study was to report the use of custom-made transport distraction osteogenesis (TPDO) in reconstruction of extensive mandibular defect. Methods: Two consecutive patients with mandibular defect involving the body and symphysis were described. Presurgical three-dimensional computed tomography and rapid prototype model were used to design the customized distractor. A bifocal TPDO was performed as immediate reconstruction after mandibulectomy. The trifocal TPDO was carried out 2 years after partial mandibulectomy as a secondary procedure. Postoperatively, patients were followed up with clinical examinations and radiographs. The distractors were removed at the end of 8 months of consolidation period. Results: Both distractors were tolerated well. Both patients had achieved soft- and hard-tissue formation. A mild infection and unexpected unilateral coronoid fracture was noted in one of the patients. However, no functional disturbance to the distractor and no adverse impact on the final result were noted. Conclusions: The use of custom-made TPDO distractor can recreate the mandibular contour in single-stage surgery and avoid the donor-site morbidity. It is a potentially valid method for extensive mandibular defect reconstruction.

Management of severe odontogenic infections in pregnancy

BACKGROUND The objective of this study was to review the management of patients presenting with severe odontogenic infections and who are also pregnant. METHODS A retrospective clinical audit was conducted of all female patients admitted to the Royal Adelaide Hospital by the Oral and Maxillofacial Surgery Unit from 1999 to 2009 with severe odontogenic infections. Pregnant patients were identified and their age, medical history, previous obstetric and gynaecological history, stage of current pregnancy, presenting infection, diagnosis and management were recorded, as well as the outcome of the pregnancy. RESULTS A total of 346 female patients were admitted to the Royal Adelaide Hospital under the care of the Oral and Maxillofacial Surgery Unit with an admission diagnosis of severe odontogenic infection and five were pregnant. Besides surgical and anaesthetic assessment, mother and foetus were assessed by the Obstetric and Gynaecology Unit. In all, five with severe infection were successfully resolved and four proceeded to a normal delivery with a healthy child. The remaining patient had an already planned therapeutic abortion. CONCLUSIONS Pregnant patients with severe odontogenic infections require urgent referral to a tertiary hospital with full surgical, anaesthetic and obstetric services. This allows appropriate management of the complex requirements of mother and foetus.

Penetrating injuries to the orbit despite safety equipment

Penetrating injuries to the orbit are uncommon but may have catastrophic consequences ranging from blindness, cerebral damage to death. Apparently similar injuries but with a slight difference in the anatomic pathway may have minimal morbidity. Prevention by the use of full safety equipment is recommended. This case report shows that full safety equipment may not prevent injury.

Modified condylar distraction osteogenesis via single preauricular incision for treatment of temporomandibular joint ankylosis.

BackgroundTemporomandibular joint (TMJ) ankylosis with facial asymmetry is still controversial to deal with. This study describes a modified condylar distraction osteogenesis protocol via preauricular approach for the treatment of this condition. MethodsFrom 2006 to 2013, 18 patients with TMJ ankylosis were enrolled. The Wuhan TMJ Ankylosis treatment protocol includes as follows: (1) preauricular approach is the only surgical access; (2) TMJ arthroplasty is used to recontour the condylar head, and the vertical height of condyle is maintained; (3) distractor placement with distractor port exiting via preauricular incision; (4) distraction after 5 to 7 days of latency period with 0.5 mm twice daily; and (5) distractor removal after 3-month consolidation through preauricular incision. All patients had clinical follow-up and detailed examination. ResultsAll patients had satisfactory results postoperatively. The mean (range) mouth opening increased from 7.1 (0–18) to 32.1 (28–43) mm during 37 (6–81) months of follow-up period (P < 0.01). Facial asymmetry was corrected in all patients, and all patients had minimal postoperative scar perception of the preauricular incision. ConclusionsThe Wuhan TMJ ankylosis protocol provides a safe and effective treatment alternative in managing TMJ ankylosis, especially in young women who are anxious about perceptive extraoral scar.