Serious Condylar Head Absorption in Children With Intracapsular Condylar Fractures Treated Operatively With Long Screws.

OBJECTIVE: This study was performed to explore bone remodelling in children with intracapsular condylar fractures after the condylar fracture fragments were fixed using long screws and to offer possible explanations about the underlying mechanism. PATIENT AND METHODS: Records of children (less than 12 y old) who sustained intracapsular condylar fractures and fixed with long screws from May 2012 to January 2015 were retrieved. Age, gender, dates of injury, admission, and discharge, mechanism of trauma, location and pattern of fracture, other mandibular fractures, treatment methods, and time of review were recorded and analyzed. Image dates of pretreatments and posttreatments, including the date of review, were also recorded. RESULTS: A total of 8 patients completed their follow-up, and all patients (n=5) who were followed up after more than 3 months showed serious resorption of the condylar head. The condylar head resorbed until the height (or articular surface) dropped and aligned with the surface of the screw. The shortest time of absorption, as shown by the computed tomography scan was 106 days, and the longest time was 171 days (average time of 141.8 d). CONCLUSIONS: Intracapsular condyle fractures in children should be managed conservatively as much as possible. However, if the height of the fracture fragments drops remarkably, open reduction and rigid internal fixation become possible choices.

Treatment of Sagittal Fracture of the Mandibular Condyle Using Resorbable-Screw Osteosynthesis.

PURPOSE: Screw osteosynthesis is advocated for the treatment of sagittal fracture of mandibular condyle (SFMC). This study aimed to explore the applicability of resorbable-screw osteosynthesis in the treatment of SFMC. METHODS: A retrospective cohort study was performed in patients with SFMC treated with resorbable-screw osteosynthesis (group A) from June 2011 through June 2021. The patients who had undergone titanium-screw osteosynthesis served as the control group (group B). The primary outcome variable was fracture healing, defined as follows: 1) normal mouth opening and restoration of pretrauma occlusion; 2) without complications or discomfort of temporomandibular joint symptoms; and 3) fracture union without abnormal reactions or bone resorption in computed tomography images. The secondary outcome variable was condylar morphological changes including radiographic imaging appearance of the condyle, mandibular ramus height (MRH), anteroposterior diameter (APD), and mediolateral diameter (MLD) of the condyle, which were assessed by comparing the computed tomography images 1 week after surgery with those of 3 months after surgery. The collected data of the outcome variables of the 2 groups were analyzed correspondingly using Student's paired t test and Student's t test. RESULTS: There were 24 patients in group A and 71 patients in group B. All the patients displayed an evident improvement in mouth opening and restored pretrauma occlusion. Few patients had complications (group A, 8.33%; group B, 9.86%) and discomfort of temporomandibular joint symptoms (group A, 16.67%; group B, 15.49%). Fracture union without abnormal reactions or bone resorption was observed during the follow-up. The radiographic evaluation revealed no significant difference in the MRH, the maximum APD, and MLD of the condyles between 1 week and 3 months after surgery in both groups. There were no significant intergroup differences in the changes in the MRH, APD, and MLD of the condyles. CONCLUSIONS: Resorbable-screw osteosynthesis is a viable option for the treatment of SFMC.

Removal of Fracture Fragments in Intracapsular Condylar Fractures: An Alternative Treatment Option.

OBJECTIVE: This study aimed to explore bone remodeling after condylar fracture fragments have been removed from patients with intracapsular condylar fractures. it also evaluated whether condyle fracture removal can be used alternatively when the authors treat patients with comminuted or small pieces of fracture or in extremely difficult operations. METHODS: Records of patients who sustained intracapsular condylar fractures and treated by removal of fragments for the period of February 2013 to September 2019 were retrieved. Data about age, gender, date of injury, dates of admission and discharge, mechanism of trauma, location and pattern of fracture, other mandibular fracture, treatment methods and time of review were recorded and analyzed. Image dates of pre- and post-treatment (including the time of review) were also recorded. RESULTS: The data of a total of 103 patients ranging from 5 to 84 years old were retrieved during this study. A total of 135 sides of condylar fragments were removed. Almost all of the patients with comminuted condyle head fracture or type A fracture presented apparent shortening of the ramus height, and none of them showed osteogenesis (or new bone formation) during their follow-up. Present study only observed osteogenesis in few patients who sustained type B/C intracapsular condylar fractures during their follow-up. The younger the patient was, the longer the follow-up time was, and the higher the possibility of new bone formation was. No correlation was found between the amount of osteogenesis and follow-up time, the amount of osteogenesis was generally small, and no patient could form a new condyle head similar to the normal (or original) condyle head. Condylar hypertrophy only occurred in children. Four patients developed temporomandibular joint ankylosis. CONCLUSIONS: Removal of fracture fragments is an alternative treatment option for patients who sustained comminuted or small pieces of fracture or in extremely difficult operations.

Maxillofacial Injuries in Pediatric Patients.

OBJECTIVE: This study aimed to evaluate and analyse the demographic characteristics and changes in maxillofacial injuries during their development in pediatric patients. METHODS: A retrospective cohort and case-control study was conducted. The sample was composed of all children (less than 10.5 years) who presented with maxillofacial injuries within a 6.5-year period (from December 2012 to April 2019). Data about age, gender, hospitalization date, mechanism of trauma, location and pattern of injuries, associated general injuries or systemic diseases, admission methods (emergency admission or not), type of anesthesia, treatment methods and hospital costs (¥) were recorded and analyzed. Data analysis included Chi-square test, Fisher exact test, and t test. Univariate and multivariate analyses were also performed. Logistic regression analysis was used to control for confounding variables. Differences at P < 0.05 were considered significant. RESULTS: A total of 643 pediatric patients were included in this study, with a boy-to-girl ratio of 1.77:1 (411 boys and 232 girls). The age range was 0.18 to 10.5 years (average of 3.23 ±â€Š1.98 years). The largest age group was patients aged 1 to 2 years (200 patients, 31.1%), followed by 2 to 3 years (139 patients, 21.6%). In the majority of patients, fall at ground level was the most common mechanism of injury (391 patients, 60.8%). In addition, 613 patients (95.3%) sustained at least maxillofacial soft-tissue injuries, while 460 (71.5%) sustained only maxillofacial soft-tissue injuries and 183 (28.5%) sustained maxillofacial fractures. Lip was the most vulnerable soft tissue to be injured (283 patients, 44.0%). Patients who sustained maxillofacial soft-tissue injuries were less prone to maxillofacial fractures than those who did not. Maxillofacial fractures were highly presented in patients with dental injuries (OR = 6.783; 95% confidence interval, 3.147-14.620; P < 0.001). Older children (> 5 years old) were at higher risk of maxillofacial fractures than younger children (≤ 5 years old, P = 0.006). The risk of maxillofacial fractures (except symphysis fractures) increased with age, especially in patients aged between 5 and 10 years. Maxillofacial soft-tissue injuries were highly distributed amongst patients aged 1 to 5 years. The number of patients who sustained only maxillofacial soft-tissue injuries gradually decreased from 2013 to 2018. Patients in emergency admission (OR = 13.375; 95% confidence interval, 1.286-139.121; P = 0.030) and treated under general anesthesia (OR = 27015.375; 95% confidence interval, 1033.046-706484.218; P < 0.001) were more prone to be treated by surgery procedure. Patients with facial fractures were less frequent to be treated by surgery procedure (OR = 0.006; 95% confidence interval, 0.000-0.575; P = 0.028); however, the mandibular symphysis (OR = 18.141; 95% confidence interval, 2.860-115.069; P = 0.002) or body fractures (OR = 71.583; 95% confidence interval, 2.358-2172.879; P = 0.014) were highly treated by surgery procedure. CONCLUSIONS: Maxillofacial fractures in pediatric patients were significantly related to age, etiology, maxillofacial soft-tissue injury, dental injury and other general injuries. Older pediatric patients were at higher risk of maxillofacial fractures (except symphysis fractures) and lower risk of maxillofacial soft-tissue injuries than younger pediatric patients. Patients in emergency admission, fractures of the symphysis or body, and treated under general anesthesia were the main reasons for surgical management.

Extracapsular Condylar Fractures Treated Conservatively in Children: Mechanism of Bone Remodelling.

OBJECTIVE: This study aims to reveal the reconstruction process in pediatric patients with extracapsular condylar fractures after conservative treatment. We clarify that the "upright" position (or "recontouring" or favorable prognosis) of condyles is not a result of the anatomical reduction of the deviated condylar processes but originates from the remodeling of the skeleton. We also explore the related mechanism. METHODS: The sample consisted of 27 pediatric patients aged less than 12 years who presented with extracapsular condylar fractures and were treated conservatively within an 8-year period (June 2011-April 2019). Data on the age, gender, date of injury, mechanism of trauma, location and pattern of mandibular condylar fracture and associated injuries and treatment methods of the patients were obtained. The process of bone remodeling in condyles was also recorded and analyzed. RESULTS: The 27 children in this study sustained 33 extracapsular condylar fractures over the 8-year period of record retrieval. Amongst these fractures, 8 (24.2%) and 25 (75.8%) were condylar neck and condylar base fractures, respectively. Deviation and green-stick fractures were the predominant types and accounted for over 3 quarters of the condylar neck and base fractures (28, 84.8%), followed by dislocation fracture (3, 9.1%), displacement fracture (1, 3.0%), and non-displaced fracture (1, 3.0%). The period of follow-up ranged from 2 days to 257 days (average, 58.78 days). Only 1 patient with bilateral extracapsular condylar fractures showed vertically reconstructed condyles, which indicates an upright position of the condylar processes. One patient showed less angulation after treatment than before treatment, 1 patient revealed greater angulation after treatment than before treatment and all other patients (20 patients) showed the same angulation pre- and post-treatment. Both patients with only extracapsular condylar fractures showed no obvious deviations in dentition and facial asymmetry after their injury and treatment. The shortest and longest times observed for bone remodeling were 33 and 256 days, respectively. Children whose condylar head remained completely or at least partly inside the glenoid fossa showed satisfactory remodeling results during follow-up. Computed tomography scan during follow-up generally showed bone regeneration in the lateral condyle articular surface and the medial portion of the ascending ramus and bone resorption in the displaced direction (ie, the medial condyle head became sharp). Condylar heads displaced completely outside of the glenoid fossa showed serious shortening of the ascending ramus, and no obvious bone remodeling was observed. Only 1 patient with bilateral extracapsular condylar fractures showed a normal contour (ie, a vertically reconstructed condyle reflecting the upright position of the condylar processes) after 8 months. CONCLUSION: Stress stimulation originating from the glenoid fossa and ascending ramus of the mandible is a prerequisite for good condylar reconstruction. Conservative treatment could be carried out if the condylar head remains completely or at least partly inside the glenoid fossa. When the condylar head is dislocated completely outside the glenoid fossa, the glenoid-condylar relationship ceases to exist, joint function is lost and the height of the ascending ramus is significantly reduced. In this case, open reduction may be suitable.

Restoration of Ramus Height in Child Patients With Extracapsular Condylar Fractures: Is This Mission Almost Impossible to Accomplish?

OBJECTIVE: This study aimed to assess whether ramus height is restored in children with extracapsular condylar fractures treated by conservative or surgery procedures. METHODS: The sample consisted of 35 children (collected consecutively) less than 12 years old who presented with extracapsular condylar fractures and treated within an 8-year period (June 2011 to April 2019). Data on the age, gender, date of injury, mechanism of trauma, location and pattern of mandibular condylar fracture, associated injuries and treatment methods were recorded and analyzed. Ramus height restoration is the main evaluation indicator during the follow-up period. RESULTS: Within the 8-year record retrieval, the 35 children sustained 41 extracapsular condylar fractures. For the sample size, 10 (24.4%) and 31 (75.6%) had condylar neck and base fractures, respectively. Deviation and green-stick fracture were the predominant types in condylar neck and base fractures, accounting for more than 3 quarters (31, 75.6%). The majority (33, 80.5%) of patients were treated with nonsurgical treatment, and 8 (19.5%) were treated by open reduction and internal fixation (ORIF). During the follow-up period (1-1419 days, average time of 110.6 days), only 1 patient (with bilateral extracapsular condylar fractures) had their ramus height restored (follow-up period, 256 days). Most members of the ORIF group (5 of 8, 62.5%) postoperatively showed bended ramus (deviated angularly/fragment angulation). CONCLUSION: Conservative treatment could hardly restore the ramus height of children with extracapsular condylar fractures. Anatomically or totally restoring the ramus height is difficult even with the surgical treatment of ORIF; however, surgical treatment of ORIF can substantially restore the ramus height for dislocated fractures or seriously displaced fractures.

Characteristic changes of traumatic dental injuries in a teaching hospital of Wuhan under transmission control measures during the COVID-19 epidemic.

BACKGROUND/AIMS: In December 2019, a novel coronavirus emerged in Wuhan City, and a retrospective analysis is necessary to provide clinicians with the characteristics of traumatic dental injuries (TDIs) during the epidemic. The aim of this study was to evaluate the changes in the characteristics of TDIs under the transmission control measures in Wuhan City utilizing an epidemiologic investigation. MATERIALS AND METHOD: In this retrospective study, epidemiologic information, including the number of patients, gender, age, and TDI parameters such as time since injury to the clinic visit, etiology, tooth location, and the type of injury was extracted from the records of patients in the hospital from two periods: period 1 (between January 23, 2020, and April 7, 2020) and period 2 (between January 23, 2019, and April 7, 2019). The data from the two periods were compared and analyzed. RESULT: A total of 158 patients were treated for TDIs (120 in 2019 and 38 in 2020). Males were more likely to suffer from TDIs than females with a ratio of 1.5:1, both in 2020 and 2019. Other than that, there were characteristic changes in TDIs during the transmission control measures in the COVID-19 epidemic, which included the number of patients, age, time since injury to the clinic visit, etiology, tooth location and the type of TDI. CONCLUSION: The transmission control measures during the COVID-19 epidemic had a significant impact on the epidemiology and etiology of TDIs in Wuhan City.

Treatment of Sagittal Fracture of the Zygomatic Arch Root Assisted by Surgical Navigation Technology.

Sagittal fracture at the temporal root of the zygomatic arch often occurs as a part of zygomaticomaxillary fractures. The authors described the application of computer-assisted navigation in the lag screw insertion for the fixation of sagittal fracture at the temporal root of zygomatic arch. Using the presurgical planning of the computer-assisted navigation system, the trajectory of lag screw insertion was designed, and the insertion depth was calculated. In the presurgical planning, the trajectory of screw insertion was placed with an anterior inclination of 10° to 15° (mean: 12.24°), and the screw insertion depth was 9.0 to 12.0 mm (mean: 10.65 mm). In the operation, the screw insertion in the fixation of the sagittal fracture was performed under the guidance of navigation system according to the presurgical planning. The postoperative CT scan showed exact reduction and fixation of the sagittal fracture in all cases. Computer-assisted navigation is a useful tool for the lag screw insertion in the precise fixation of sagittal fracture at the temporal root of the zygomatic arch in complex zygomaticomaxillary fractures.

AG490 suppresses interleukin-34-mediated osteoclastogenesis in mice bone marrow macrophages.

Interleukin-34 (IL-34) has been recently identified as a novel cytokine, substituting for the function of macrophage colony-stimulating factor (M-CSF), a pivotal osteoclastogenic factor involved in bone-related diseases (e.g., osteomyelitis of the jaws). However, the molecular mechanisms are not fully understood. This study aimed to explore the potential mechanism of IL-34 in receptor activator of NF-kB ligand (RANKL)-induced osteoclast formation. We found that IL-34 alone significantly maintained the survival of bone marrow macrophages (BMMs) and enhanced the expression of the osteoclast-related genes TRAP, Ctsk, and NFATc1, as well as TRAP-positive multinucleated cells combined with RANKL, which can be reversed by AG490. Conversely, AG490 did not affect the M-CSF-mediated osteoclastogenesis in the presence of RANKL. The protein expression of p-STAT3 in BMMs was enhanced by IL-34 combined with RANKL compared with RANKL alone, and AG490 inhibited the expression of p-SATA3 at protein level in the IL-34 plus RANKL group, resulting in significantly increased Smad7 expression. This study demonstrated for the first time that IL-34 may play a crucial role in RANKL-induced osteoclastogenesis by promoting the proliferation and differentiation of BMMs, stimulating p-STAT3 expression, and inhibiting the expression of Smad7 in the absence of M-CSF.

Platelet-derived growth factor BB enhances osteoclast formation and osteoclast precursor cell chemotaxis.

Enhanced osteoclast formation increases bone resorption, which triggers bone remodeling. Platelet-derived growth factor BB (PDGF-BB) enhances precursor cell homing, angiogenesis, and bone healing, and thereby could also treat osteoporosis. However, the effect of PDGF-BB on osteoclast formation is not fully understood. We investigated whether exogenous recombinant PDGF-BB directly affects osteoclast formation and osteoclast precursor cell chemotaxis. The murine monocyte-macrophage cell line RAW264.7 and bone-marrow-derived macrophages were cultured with recombinant mouse PDGF-BB with or without a platelet-derived growth factor receptor ß inhibitor (AG-1295) or a Janus kinase 2 inhibitor (AG-490) to analyze the effect on osteoclastogenesis in vitro. PDGF-BB with or without AG-490 or AG-1295 was locally administrated in the mandibular fracture of 16-week-old Sprague Dawley rats (n = 18) for 1-2 weeks to analyze the effect on osteoclastogenesis in vivo. The effect of the treatments on osteoclast formation, osteoclast precursor cell migration, and expression of osteoclastogenic signaling molecules was analyzed. PDGF-BB enhanced osteoclast formation both in vitro and in vivo, but AG-490 and AG-1295 inhibited this effect. PDGF-BB enhanced phosphorylation of extracellular-signal-regulated kinase 1/2 (ERK1/2), Akt, and signal transducer and activator of transcription 3 (STAT3) in RAW264.7 cells. AG-490 inhibited PDGF-BB-induced STAT3 phosphorylation. PDGF-BB enhanced RAW264.7 cell migration and gene expression of osteoclastogenic signaling molecules (i.e., nuclear factor of activated T cells 1, dendrocyte-expressed seven transmembrane protein, and B-cell lymphoma 2), and treatment with AG-1295, AG-490, or S3I-201 (a STAT3 inhibitor) reduced this effect. PDGF-BB enhanced osteoclast formation, osteoclast precursor cell chemotaxis, and phosphorylation of STAT3, Akt, and ERK1/2. but AG-1295 and AG-490 reduced this effect. These findings reflect the complexity of PDGF-BB in bone biology.

Use of Computer-Assisted Navigation in the Retrieval of Accidentally Displaced Third Molars.

PURPOSE: The purpose of this study was to describe the application of computer-assisted navigation for the retrieval of accidentally displaced mandibular third molars. PATIENTS AND METHODS: All patients identified as having an accidentally displaced mandibular third molar or root fragment and presented to the authors' department from April 2013 through June 2015 were included in this prospective study. Retrieval of the displaced molar was performed in these patients under the guidance of computer-assisted navigation, in which a registered forceps was used to clamp and retrieve the molar. Postoperative complications were assessed for all patients. RESULTS: Twelve patients were included in this case series. Using computer-assisted navigation, the operation proceeded successfully in all patients. These patients displayed uneventful healing without postoperative complications. CONCLUSION: Computer-assisted navigation is a safe, straightforward, and minimally invasive treatment method that can be applied for the retrieval of accidentally displaced third molars. It is recommended as an intraoperative tool for the retrieval of teeth or tooth fragments displaced into areas that are difficult to access.

Applications of Computer-Assisted Navigation for the Minimally Invasive Reduction of Isolated Zygomatic Arch Fractures.

PURPOSE: Computer-assisted navigation has been widely used in oral and maxillofacial surgery. The purpose of this study was to describe the applications of computer-assisted navigation for the minimally invasive reduction of isolated zygomatic arch fractures. PATIENTS AND METHODS: All patients identified as having isolated zygomatic arch fractures presenting to the authors' department from April 2013 through November 2014 were included in this prospective study. Minimally invasive reductions of isolated zygomatic arch fractures were performed on these patients under the guidance of computer-assisted navigation. The reduction status was evaluated by postoperative computed tomography (CT) 1 week after the operation. Postoperative complications and facial contours were evaluated during follow-up. Functional recovery was evaluated by the difference between the preoperative maximum interincisal mouth opening and that at the final follow-up. RESULTS: Twenty-three patients were included in this case series. The operation proceeded well in all patients. Postoperatively, all patients displayed uneventful healing without postoperative complication. Postoperative CT showed exact reduction in all cases. Satisfactory facial contour and functional recovery were observed in all patients. The preoperative maximal mouth opening ranged from 8 to 25 mm, and the maximal mouth opening at the final follow-up ranged from 36 to 42 mm. CONCLUSIONS: Computer-assisted navigation can be used not only for guiding zygomatic arch fracture reduction, but also for assessing reduction. Computer-assisted navigation is an effective and minimally invasive technique that can be applied in the reduction of isolated zygomatic arch fractures.

Maxillofacial Fractures in Women and Men: A 10-Year Retrospective Study.

PURPOSE: The purpose of this study was to evaluate and compare the demographic characteristics of maxillofacial fractures between women and men in China. PATIENTS AND METHODS: The sample was composed of all patients who sustained maxillofacial fractures during a 10-year period (2000 through 2009). Incidences, age distributions, etiologies, fracture patterns, associated injuries, and occupation distributions were recorded and analyzed. Data analysis included the χ(2) test, the Fisher exact test, and the t test. A P value less than .05 was considered significant. RESULTS: There were 1,131 patients (881 male and 250 female) who sustained maxillofacial fractures, with a male-to-female ratio of 3.5:1. Male patients sustained injuries most frequently during the autumn (P = .048), whereas female patients sustained more maxillofacial injuries during the summer (P = .006). Men sustained motorcycle (P = .023) and assault-related accidents (P = .036) more frequently than women, whereas women were more frequently injured in bicycle-related accidents (P < .001) or falling while at ground level (P = .001) than men. Women presented more frequently with condylar fracture than men (P = .028), whereas men were more prone to symphysis fractures than women (P = .037). For drivers, only men were involved (P = .001). Male workers sustained maxillofacial fractures more frequently than female workers (P < .001). Female children, students, and company staff were more prone to maxillofacial fractures than their male counterparts (P = .010, P = .004, and P = .044 respectively). CONCLUSIONS: The demographic characteristics of maxillofacial fractures in female patients considerably differ from those in male patients.

Resorbable plates for the fixation of isolated mandibular angle fracture.

PURPOSE: This study was designed to evaluate the results in isolated mandibular angle fractures treated with resorbable plates and to summarize experiences of the application of resorbable plates. PATIENTS AND METHODS: Ten patients (6 men and 4 women) with isolated displaced mandibular angle fracture were included in this case series. Open reduction by intraoral or extraoral approach was performed, and the fractures were fixed using single or dual resorbable plates. Postoperatively, follow-up was undertaken to evaluate the fracture healing and the degradation of resorbable plates. RESULTS: All the fractures healed without complications during the follow-up period. No screw or plate fractured during the surgery, no dislocation of the fracture segment after the fixation by resorbable plates, and no foreign body reaction related with resorbable plates were observed. CONCLUSIONS: With proper indication, resorbable plates are suitable for the fixation of isolated mandibular angle fractures. Single or dual resorbable plates by intraoral or extraoral approach can be individualized on the basis of the patients' condition.

Traumatic head injuries in patients with maxillofacial fractures: a retrospective case-control study.

OBJECTIVES: To analyse and evaluate the correlation between traumatic head injuries (THIs) and maxillofacial fractures (MF). Age, gender and trauma mechanism correlated with THI were also investigated. PATIENTS AND METHODS: We conducted a hospital-based retrospective case-control study at Stomatology College and Hospital, Wuhan University. From January 2000 to December 2009, a total of 1131 patients with MF were enrolled in the statistical study to evaluate the association of THI and other risk factors with MF. Among these patients, 86 presented with THI. We utilized binary logistic regression and risk analysis to investigate the associations among MF and other risk factors with HI. RESULTS: Head injuries (103 injuries) were sustained by 86 patients (7.6%), with male-to-female ratio of 4.1:1.0. Most of the patients (52 patients, 50.5%) also exhibited cranial bone fractures. The age group with most patients was the 30-39 years age group (26 patients, 30.2%), followed by the 19-29 years age group (22 patients, 25.6%). Motor vehicle accident (MVA) was the most common mechanism of injury (49 patients, 74.1%). Patients older than 50 years showed the highest risk for head injury (OR, 2.0; 95% confidence interval, 1.1-3.7; P = 0.025). MVA had a sixfold risk of head injury (OR, 6.2; 95% confidence interval, 1.5-26.1; P = 0.013). Head injuries were more prone to occur in patients who had combined fracture of the mid-face and mandible (OR = 4.6, P < 0.001), and only a 0.3-fold risk of multimandible fractures (P < 0.001), 0.5-fold risk of single mandibular fracture (P = 0.017) and 0.3-fold risk of patients who sustained only single mandibular condylar fracture (P = 0.019). CONCLUSIONS: The occurrence of head injuries is significantly related to age, aetiology and the pattern and position of maxillofacial fractures.

The root canal system: a channel through which we can seed cells into grafts.

Bone tissue engineering is bringing hope to patients with jawbone defects, but this technology works well only for small- to moderate-sized jawbone defects. For large segmental jawbone defects, it is difficult to form the functional vascular networks within the graft due to limited diffusion of nutrition and uneven distribution of seed cells. From the standpoint of bionics, seed cells should be continuously transmitted into the graft to replace the necrotic cells during the entire process of bones regeneration. However, the existing one-time inoculation method (OIM) fails to achieve this goal because it is almost impossible to re-open the wound and inoculate cells into grafts that have already been implanted into the body. Inspired by the anatomical structure of jawbones, we hypothesize that the root canal in teeth of jawbones could be used as a channel through which seed cells could be delivered into the graft. Therefore, the multiple-times inoculation method (MIM) could be achieved via the root canal system if defects are located on the maxillofacial bones with teeth. Both osteogenesis and vascularization would be promoted to a large extent because the engineered construct has a limitless supply of seed cells and growth factors.

Maxillofacial injuries in infants and preschools: a 2.5-year study.

PURPOSE: This study aims to evaluate the epidemiology of maxillofacial injuries in infants and preschools. PATIENTS AND METHODS: The data from 110 infants and preschools with maxillofacial injuries from October 2010 to March 2013 were analyzed retrospectively. RESULTS: The male-to-female ratio was 1.89:1. The peak age was 1 to 3 years (53.64%). Accident falls (76.36%) were the major cause. A total of 166 soft-tissue injuries were found in 103 patients, 102 dental traumas in 36 patients, and 53 maxillofacial fractures in 33 patients. The most common sites of soft-tissue injuries included the gingiva (17.47%), lower lip (13.86%), upper lip (13.25%), and chin (12.05%), and the majority were lacerations (77.71%). Dental traumas occurred mainly in incisors (81.37%) and the lower arch (60.78%). Of the 53 fractures, the most common sites were the condyle (45.28%), symphysis (22.64%), and mandibular body (16.98%); 28 (52.83%) were treated by operation and 25 (47.17%) by conservative treatment. CONCLUSIONS: Maxillofacial injuries in infants and preschools exhibit specific epidemiological features. These are related to anatomic, physiologic, and psychologic development in infants and preschools.

Ocular trauma in patients with maxillofacial fractures.

PURPOSE: The purpose of this study was to analyze and evaluate ocular injuries in patients with maxillofacial fractures. Correlation of the ocular injury and patients' age, sex, trauma mechanism, and type of maxillofacial fracture was also investigated. MATERIALS AND METHODS: From January 2000 to December 2009, a total of 1131 patients with facial fractures were registered. The information and data collected and analyzed included the following: age, sex, mechanism of injury, type of facial fracture, type of ocular injury, and the relationship between ocular injury and facial fracture. RESULTS: Ocular injury (349 injuries) was sustained by 209 patients (18.5%), with a male/female ratio of 5.33:1 (176 males and 33 females). The age range of the patients associated with ocular trauma was 3 to 68 years (mean [SD], 32.40 [11.27] y). Patients aged 30 to 39 years showed the highest risk for ocular trauma (odds ratio [OR], 1.852; P < 0.001). Children showed the lowest risk for ocular injuries (OR, 0.162; P < 0.001). Motor vehicle accidents were the most common mechanism of injury (97 patients, 46.4%). Motor vehicle accidents also had a 2.243-fold risk for ocular trauma (OR, 2.243; P = 0.021). Ocular traumas were more prone to occur in patients who sustained midfacial fractures (OR, 10.232; P < 0.001), especially the patients with multiple midfacial fractures (OR, 12.389; P < 0.001). Fracture of the mandible had the lowest risk for ocular injuries (multimandibular fractures: OR, 0.035, P < 0.001; single mandibular fracture: OR, 0.151; P < 0.001). CONCLUSIONS: The occurrence of ocular injuries was significantly related to sex, age, etiology, as well as the pattern and position of the maxillofacial fractures.

Changing pattern in the characteristics of maxillofacial fractures.

PURPOSE: This study was designed to assess the changes in the etiology, incidence, and pattern of maxillofacial fractures during 2 different study periods in our department. PATIENTS AND METHODS: In this retrospective study, patients treated for maxillofacial fractures at our department from January 2000 to December 2009 were included. Data regarding patient's age, sex, etiology of fracture, time of injury, site of fracture, and pattern of fracture were collected and grouped chronologically into two 5-year periods: 2000 to 2004 (period 1) and 2005 to 2009 (period 2); the results of the study during these periods were analyzed and compared. RESULTS: A total of 1131 patients sustained maxillofacial fractures: 422 in the first period and 709 in the second period. During the second period, the male-female ratio increased from 3.35:1 to 3.63:1. Road traffic accidents remained the major etiologic factor, which increased remarkably from 49.3% to 54.6% (P = 0.085), whereas assault-related injuries decreased significantly from 16.8% to 12.4% (P = 0.039). The proportion of patients with mandibular fractures decreased from 59.6% to 55.3% (P = 0.037), whereas the proportion of patients with midfacial fractures increased from 40.4% to 44.7% (P = 0.037). CONCLUSIONS: The changing pattern of maxillofacial fractures in our center is correlated to the socioeconomic status, population mobility, and etiologic factors. Strict enforcement of traffic laws and regulations is still a focal factor in attaining appreciable reduction in maxillofacial fractures associated with road traffic accidents.

Dental trauma in patients with single mandibular fractures.

PURPOSE: The purposes of this study were to investigate the occurrence and patterns of dental trauma in patients with single mandibular fracture and to evaluate the relationships between dental injury and fracture site of mandible. MATERIALS AND METHODS: From January 2000 to December 2009, 869 patients with mandibular fractures were registered. Only the patients with single mandibular fracture were included. The information and data collected included age, gender, mechanism of injury, type of mandibular fracture, and type of dental injury. RESULTS: Single mandibular fractures were sustained in 294 (33.8%) patients. Of these, 43.5% (128 patients) presented with associated dental injuries (509 injured teeth). The patients' male/female ratio was 2.46:1 (91 males and 37 females). Patients in 30-39 year age group possessed the highest risk of suffering dental trauma (odds ratio = 2.004, P = 0.014). Road traffic accidents were the most common mechanism of injury (54, 42.2%). Lower-anterior teeth were more often injured in patients with symphysis fracture (P < 0.001), and patients with condylar fracture more frequently sustained upper-posterior teeth injury (P < 0.001). Lower-posterior teeth injury was mostly found in patients with mandibular body fracture (P < 0.001) or angle fracture (P < 0.001). Dental injuries were more prone to occur in patients who sustained only symphysis fractures (odds ratio = 3.283, P < 0.001), and the risk was only 0.193-fold in patients who sustained only mandible angle fractures (odds ratio = 0.193, P < 0.001). CONCLUSIONS: The occurrence and type of dental injury were significantly related to the fracture site of mandible.