Oral and Maxillofacial Surgery

Opioid Prescription Following Third Molar Extractions Publication date: Available online 27 April 2019 Source: Journal of Oral and Maxillofacial Surgery Author(s): Gayathri Subramanian, Samuel Y.P. Quek

Prolonged Dysphagia After Orthognathic Surgery Publication date: Available online 27 April 2019 Source: Journal of Oral and Maxillofacial Surgery Author(s): Roger A. Meyer

Condylotomy To Reverse Temporomandibular Joint Osteoarthritis In Rabbits Publication date: Available online 26 April 2019 Source: Journal of Oral and Maxillofacial Surgery Author(s): Edela Puricelli, Felipe Ernesto Artuzi, Deise Ponzoni, Alexandre Silva Quevedo Abstract Purpose Osteoarthritis of the temporomandibular joint (TMJ OA) is characterized by local tissue degeneration and pain. Treatments aim to reduce symptoms, and only some of them interfere with the progression of pathophysiological changes caused by osteoarthritis. Condylotomy is an alternative for the treatment of patients refractory to conventional treatments. The aim of this animal study was to investigate the influence of condylotomy on TMJ OA in New Zealand rabbits. Methods The animals (n=36) were divided into three groups: osteoarthritis group (OG, induced osteoarthritis), treatment group (TG, induced osteoarthritis + condylotomy), and control group (CG, with neither osteoarthritis nor surgery). Disease was induced using intra-articular monosodium iodoacetate injection for 40 days. Animals in the treatment group underwent condylotomy and were killed 20, 40 and 60 days after treatment. Animals in the control and osteoarthritis groups were killed at the same time points. Results Articular joint condition was better in TG animals on day 60 after surgery (p=0.032). Direct comparison revealed regression of TMJ OA over time among treated animals (p=0.008). Surgical treatment promoted mandibular condylar remodeling in animals in the treatment group, thus reversing tissue degeneration caused by osteoarthritis. Conclusion Therefore, our findings suggest that condylotomy may be an option for the treatment of osteoarthritis and prevent damage to TMJ structures. This may be particularly important for patients who do not respond satisfactorily to more conservative treatments.

Temporomandibular Joint Condyle-Disc Morphometric Sexual Dimorphisms Independent of Skull Scaling Publication date: Available online 25 April 2019 Source: Journal of Oral and Maxillofacial Surgery Author(s): Matthew C. Coombs, Xin She, Truman R. Brown, Elizabeth H. Slate, Janice S. Lee, Hai Yao ABSTRACT Purpose Approximately 2-4% of the U.S. population are estimated to seek treatment for temporomandibular symptoms, predominately affecting women. The study purpose was to determine whether sex-specific differences in temporomandibular morphometry result from scaling with sex differences in skull size and shape, or intrinsic sex-specific differences. Materials and Methods Eleven male (74.5±9.1 years) and eleven female (73.6±12.8 years) human cadaveric heads with no history of temporomandibular disc derangement underwent CBCT and high-resolution MRI scanning to determine three-dimensional cephalometric parameters and temporomandibular morphometric outcomes. Regression models between morphometric outcomes and cephalometric parameters were developed, and intrinsic sex-specific differences in temporomandibular morphometry normalized by cephalometric parameters were determined. Subject-specific finite element (FE) models of the extreme male and extreme female conditions were developed to predict variations in articular disc stress-strain under a same joint loading. Results In some cases, sex differences in temporomandibular morphometric parameters could be explained by linear scaling with skull size and shape; however, scaling alone could not fully account for some differences between sexes, indicating intrinsic sex-specific differences. Intrinsic sex-specific differences in temporomandibular morphometry were increased condylar medial length and mediolateral disc lengths for males, and longer anteroposterior disc lengths in females. Considering the extreme male and female temporomandibular morphometry observed in this study, subject-specific FE models resulted in sex differences with the extreme male joint having a broadly distributed stress field and peak stress of 5.28MPa, while the extreme female joint had a concentrated stress field and peak stress of 7.37MPa. Conclusion Intrinsic sex-specific differences independent of scaling with donor skull size were identified in temporomandibular morphometry. Understanding intrinsic sex-specific morphometric differences is critical to determining temporomandibular biomechanics given the impact of anatomy on joint contact mechanics and stress-strain distributions, and requires further study as one potential factor for the increased predisposition of women to temporomandibular disc derangement.

Inferior alveolar nerve block by the anterior technique anesthetizes the buccal nerve and improves anesthesia success rate for third molar extraction: a randomized controlled trial and magnetic resonance imaging evaluation Publication date: Available online 25 April 2019 Source: Journal of Oral and Maxillofacial Surgery Author(s): Shota Tsukimoto, Yoshihiro Takasugi, Risa Aoki, Motoshi Kimura, Tatsuo Konishi Abstract Purpose Lack of anesthesia of the buccal nerve and insufficient volume of anesthetic are reportedly responsible for failed inferior alveolar nerve blocks (IANB) by the Halsted approach (conventional IANB). This study aimed to determine the extent of anesthesia in the buccal nerve innervation area and to evaluate the anesthetic efficacy of injecting a larger volume of anesthetic during IANB by the anterior approach (anterior technique) in clinical settings and with magnetic resonance imaging (MRI) analysis. Patients and Methods The prospective randomized controlled trial was performed in patients scheduled for removal of a mandibular third molar. The primary predictor variables were the approach for IANB (anterior technique and conventional IANB) and anesthetic dose (1.8 and 2.7 mL). The primary outcome variables were extent of anesthesia and anesthesia success rate defined as unnecessary additional anesthesia. The secondary outcome variable was anesthetic drug distribution related to the pterygomandibular space measured on MRI-T2WIs. Statistical independence of anesthesia success rate among primary predictor variables was tested with statistical significance set at p ≤ 0.05. Results One hundred eight patients and 10 volunteers were enrolled in the clinical and MRI studies, respectively. Anesthesia of the buccal nerve was evident in patients receiving the anterior technique with 2.7 mL of anesthetic. The success rate of the anterior technique with 2.7 mL of anesthetic (96%) was higher than that with 1.8 mL of anesthetic (67%) (p=0.0113), while increasing dose had no effect on the efficacy of conventional IANB (78% and 81%, p=1.000). The MRI study revealed distribution of the anesthetic over the anterior surface of the temporalis tendon and in the pterygomandibular space following the anterior technique. Conclusion Anesthesia of the buccal nerve following the anterior technique with 2.7 mL of anesthetic solution might contribute to increasing the success rate of anesthesia for removal of mandibular third molars.

Does Single Dose Preemptive Intravenous Ibuprofen Reduce Postoperative Pain Following Third Molar Surgery? A Prospective, Randomized, Double-Blind Clinical Study Publication date: Available online 25 April 2019 Source: Journal of Oral and Maxillofacial Surgery Author(s): Ahmet Emin Demirbas, Mustafa Karakaya, Suheyb Bilge, Dilek Gunay Canpolat, Nükhet Kütük, Alper Alkan Abstract Purpose The aim of this study is to identify the preemptive analgesic effect of intravenous (IV) ibuprofen in mandibular third molar surgery. Material and Method 75 patients were randomly divided into 3 groups; Group 1 received IV ibuprofen 60 min before surgery and IV placebo (100 mL saline) after surgery; group 2 received IV placebo (100 mL saline) before surgery and IV ibuprofen 60 min after surgery; group 3 received IV placebo (100 mL Saline) 60 min before and after surgery. Postoperative pain was recorded on a visual analogue scale (VAS) at 1, 2, 4, 6, 8, 12 and 24 h within the postoperative period. The total dose of rescue acetaminophen intake was recorded during first 24 h of the postoperative period. Results The efficacy of post-surgical analgesia was greater within the preoperative IV ibuprofen group when compared to the other groups (p<0.001). The placebo group received more rescue analgesia within the first hour, when compared to the others. The average dose of acetaminophen administered within group 1 was 640 mg, compared to 1240 mg within group 2 and 1840 mg within group 3, within the first 24 h after surgery (p<0.001). Conclusion According this study, the preemptive use of IV ibuprofen resulted in less pain and a decrease in the requirement for rescue analgesia during the first 24 h following third molar surgery.

Biomechanical evaluation of mandibular condyle fracture osteosynthesis using the rhombic 3D condylar fracture plate Publication date: Available online 25 April 2019 Source: Journal of Oral and Maxillofacial Surgery Author(s): Anas Ben Achour, Heike Meißner, Uwe Teicher, Dominik Haim, Ursula Range, Alexander Brosius, Henry Leonhardt, Günter Lauer Purpose The aim of this study was to evaluate the biomechanical stability of osteosynthesis in mandibular condyle fractures using a newly designed rhombic 3D condylar fracture plate and to compare it with that using the standard two 4-hole miniplates and with that in non-fractured condyles. Material and Methods On 200 porcine mandibles, three different monocortical plating techniques were evaluated. The condyles were fractured along a defined line tangential through the sigmoid notch perpendicular to the posterior border. After anatomical reduction osteosynthesis was performed using either standard rhombic 3D condylar fracture plates and standard screws (A) or locking rhombic 3D condylar fracture plates which were fixed either with standard (B) or locking screws (C). For comparison, non-fractured condyles (D) and condyles fixed with the standard two 4-hole miniplates and 8 screws were included (E). In a universal mechanical testing machine TIRA Test 2720 each group was subjected to linear loading in the directions: lateral to medial, medial to lateral, anterior to posterior and posterior to anterior. Maximum axial force and displacement at maximum force were measured. Mean values were compared for statistical significance using analysis of variance (ANOVA) with Bonferroni correction (significance at p < 0.05). Results The main mode of failure in the plating techniques investigated was the pull-out of screws from the proximal fragment. There is no significant difference in the stability of osteosynthesis between the two 4-hole miniplates and the rhombic 3D condylar fracture plate when loading from posterior to anterior, lateral to medial and medial to lateral. However, when loading from anterior to posterior a statistically significant difference among the standard and locking system and the two 4-hole miniplates was observed, the latter being more stable. Conclusion The results of this biomechanical study suggest that the rhombic 3D condylar fracture plates are suitable for the treatment of condylar neck fractures. Both types of the plate are able to resist physiologic strains comparable to the two 4-hole miniplates.

Bibliometric analysis of Medication-Related Osteonecrosis of the Jaw: high citation rates but low evidence. Publication date: Available online 23 April 2019 Source: Journal of Oral and Maxillofacial Surgery Author(s): Márcio Diniz-Freitas, Maite Pena-Cristobal, Daniel Pérez-López, Lucía Lago-Méndez, Javier Fernández-Feijoo, Jacobo Limeres Abstract Purpose Citation analysis is one of the most commonly employed bibliometric tools for measuring the academic importance of an article in a specific area of knowledge. The objective of this study was to identify the 100 most cited articles on medication related osteonecrosis of the jaw, determine their main bibliometric characteristics and identify the bibliometric variables that affect the citation rates. Methods We performed a literature search in the Scopus database to determine the number of MRONJ article citations up to September 30, 2018. We then selected the 100 most referenced articles and gathered the following information: ranking based on the number of citations; citation density; number and names of authors; language and year of publication; country and institution of origin; financial support; publishing journal's name, impact factor, category and quartile; type of research; evidence level; and area of study. Results The top 100 publications had a mean citation density of 21.7 ± 20.7 (range, 6.2–99.4) and an h-index of 96. The 100 most cited articles on MRONJ were published in 42 scientific journals, classified into 10 separate categories of the Journal Citation Reports; 56% of the articles were in the first quartile of their category. Most of the studies were classified with a level of evidence of 4 (n=45) or 5 (n=29). In the bivariate analyses, only conflict of interest (P= 0.002), was associated with citation density. After adjusting for numerous variables, conflict of interest (r=0.27; P=0.020) and country of first author (r=0.23; P=0.043) were significantly associated with citation density. Conclusions The 100 most cited articles on MRONJ had a large number of citations and were published in journals with a high impact factor; however, the articles had a generally low evidence level and lacked randomized clinical trials.

CTRead – A Revolutionary Approach to Training Residents in CT Facial Bones Interpretation Publication date: Available online 23 April 2019 Source: Journal of Oral and Maxillofacial Surgery Author(s): Wendall Mascarenhas, Daniel Richmond, Chiasson Genevieve Abstract Purpose The purpose of our study was to create an online, web-based training module that would instruct a group of residents in the interpretation of a CT facial bones scan in a logical, step-wise manner to locate and identify all relevant facial fractures. The investigator's hypothesis was implementing the CTRead facial bones training module would improve residents' competency in the interpretation of CT facial bones scans. Methods The investigators designed and implemented a prospective quasi-experimental trial. The population for this study included medical and dental residents. The primary outcome variable was the difference between the pre and post-test scores of the participants, and the frequency of missing fractures before and after the course. Secondary outcomes of interest are subjective data gathered from the course, including participants feedback as well as subjective evaluation of the training module and perceived benefit. Another secondary outcome measured was the resident's self-reported confidence level in interpreting CT facial bones scans on their own before and after completion of the course. Descriptive and bivariate statistics were used. Results The population sample consisted of 38 residents from North America, aged 25-34 (M=28.2) years of age. When comparing the results pre and post-course, the overall frequency of missed fractures decreased from 20.7 to 6.4 (p <0.001), and the total score overall increased from 32.7 to 74.7% (p <0.001). Regarding secondary outcomes, the majority of participants indicated that they "Agree" or "Strongly Agree" with a number of positive subjective questions asked. In addition, there was a statistically significant increase in the participants' comfort levels in the interpretation of CT facial bones scans. Conclusion The results of this study confirm the hypothesis that completing the CTRead training module (www.CTRead.ca) improves competency among residents in the interpretation of CT facial bones scans and their identification of facial fractures correctly.

Helmets Decrease Risk for Bicyclist-related Maxillofacial Injuries, but not Severity Publication date: Available online 23 April 2019 Source: Journal of Oral and Maxillofacial Surgery Author(s): Marcus J. Hwang, Jasjit K. Dillon, Thomas B. Dodson ABSTRACT Purpose Given the increasing use of bicycles for local transportation and recreation, the purpose of this study is to measure the effects of bicycle helmets on frequency and severity of maxillofacial injuries. The specific aims were to measure and compare the frequencies and severity of maxillofacial injuries between injured bicyclists who did or did not wear helmets. Methods The authors implemented a retrospective cohort study and enrolled a sample of bicyclists injured between January 4, 2012 and March 31, 2018 who presented to Harborview Medical Center for evaluation and treatment. The primary predictor variable was helmet use (yes/no). The primary outcome variables were 1) presence of a maxillofacial injury (yes/no) and 2) injury severity measured using the Face Abbreviated Injury Scale (FAIS). Other study variables were grouped into demographic or injury-related variables. Appropriate uni-, bi-, and multiple logistic regressions statistics were computed, and statistical significance was set at p < 0.05. Results The sample was composed of 1379 subjects with a mean age of 39.6 ± 18.9 (1 - 91) years and 78.4% were male. The frequencies of facial injuries between helmeted and non-helmeted bicyclists were 17.3% and 30.6%, respectively (relative risk = 0.6, 95% CI = 0.5 - 0.7, p < 0.0001). The protective effect held after adjusting for age, sex, and alcohol exposure. The FAIS between helmeted and non-helmeted riders was 1.8 ± 0.5 versus 1.9 ± 0.6 (p = 0.8), respectively. Conclusions Helmeted bicyclists were 40% less likely to have a facial injury from bicycle accidents. For cyclists who did have a facial injury, however, injury severity was not different between helmet and non-helmeted wearers. This may be due to the fact that unlike American football helmets, standard bicycle helmets do not include a face mask to protect the face.