Deciphering Early-Stage Molecular Mechanisms of Negative Pressure Wound Therapy in a Murine Model.

Negative Pressure Wound Therapy (NPWT) is a commonly employed clinical strategy for wound healing, yet its early-stage mechanisms remain poorly understood. To address this knowledge gap and overcome the limitations of human trials, we establish an NPWT C57BL/6JNarl mouse model to investigate the molecular mechanisms involved in NPWT. In this study, we investigate the intricate molecular mechanisms through which NPWT expedites wound healing. Our focus is on NPWT's modulation of inflammatory immune responses and the concurrent orchestration of multiple signal transduction pathways, resulting in shortened coagulation time and reduced inflammation. Notably, we observe a significant rise in dickkopf-related protein 1 (DKK-1) concentration during NPWT, promoting the differentiation of Hair Follicle Stem Cells (HFSCs) into epidermal cells, expediting wound closure. Under negative pressure, macrophages express and release DKK-1 cytokines, crucial for stimulating HFSC differentiation, as validated in animal experiments and in vitro studies. Our findings illuminate the inflammatory dynamics under NPWT, revealing potential signal transduction pathways. The proposed framework, involving early hemostasis, balanced inflammation, and macrophage-mediated DKK-1 induction, provides a novel perspective on enhancing wound healing during NPWT. Furthermore, these insights lay the groundwork for future pharmacological advancements in managing extensive wounds, opening avenues for targeted therapeutic interventions in wound care.

Surface Modification of Polylactic Acid Bioscaffold Fabricated via 3D Printing for Craniofacial Bone Tissue Engineering.

Bone tissue engineering is a promising solution for advanced bone defect reconstruction after severe trauma. In bone tissue engineering, scaffolds in three-dimensional (3D) structures are crucial components for cell growth, migration, and infiltration. The three-dimensional printing technique is well suited to manufacturing scaffolds since it can fabricate scaffolds with highly complex designs under good internal structural control. In the current study, the 3D printing technique was utilized to produce polylactic acid (PLA) scaffolds. BMSCs were seeded onto selected scaffolds, either hydrogel-mixed or not, and cultivated in vitro to investigate the osteogenic potential in each group. After osteogenic incubation in vitro, BMSC-seeded scaffolds were implanted onto rat cranium defects, and bone regeneration was observed after 12 weeks. Our results demonstrated that BMSCs were able to seed onto 3D-printed PLA scaffolds under high-resolution observation. Real-time PCR analysis showed their osteogenic ability, which could be further improved after BMSCs were mixed with hydrogel. The in vivo study showed significantly increased bone regeneration when rats' cranium defects were implanted with a hydrogel-mixed BMSC-seeded scaffold compared to the control and those without cell or hydrogel groups. This study showed that 3D-printed PLA scaffolds are a feasible option for BMSC cultivation and osteogenic differentiation. After mixing with hydrogel, BMSC-seeded 3D-printed scaffolds can facilitate bone regeneration.

Computer-assisted Simulation-based Modification of Sagittal Split Osteotomy in Class II Asymmetry: Optimizing Bone Contact Between Proximal and Distal Segments.

BACKGROUND: Computer-assisted surgical simulation (CASS) allows more precise orthognathic surgery. However, few studies have evaluated associations between CASS-designed bilateral sagittal split osteotomy (BSSO) and bone contact surface in class II mandibular asymmetry. This study aims to evaluate the effects of using computer-assisted simulation and design modification of sagittal split osteotomy (SSO) to improve bony contact in skeletal class II asymmetry. METHODS: This retrospective analysis reviewed 28 patients with class II asymmetry who underwent orthognathic surgery, including 15 with modified SSO (group CS) and 13 with conventional SSO (group C). Modified SSO was designed under CASS. Operative characteristics, postoperative outcomes, and complications were collected and compared between the two groups. RESULTS: Bony contact was found at the distal end of the proximal segment in all group CS patients, while bone gap was noted in all group C patients (p<0.05). Moreover, bone graft was used in four group C patients but was not used in all cases group CS patients (p<0.05). A trend toward lower operative time or perioperative bleeding was noted in group CS, but without statistical significance. After 1-year follow-up, inferior alveolar nerve disturbances were noted in two group CS patients and one group C patient. Palpable bone gap with uneven jaw line was noted in two group C patients one year after surgery and one patient received fat graft treatment. CONCLUSION: The simulation-based sagittal split osteotomy modification provides appropriate contact surface and eliminates the bone gap between proximal and distal segments in class II asymmetry.

Facial Fracture Patterns and Severity of Associated Injuries After Motorcycle Accidents.

BACKGROUND: Motorcycle injuries remain a significant cause of motor vehicle-related morbidity and mortality in Taiwan. Besides, the facial region is a commonly fractured site under motorcycle accidents. To date, there are no trauma mechanism-based studies of facial fractures. AIM AND OBJECTIVES: This study aims to determine the facial fracture patterns, the severity of head trauma, and associated injuries by different motorcycle-related trauma mechanisms enabling a greater understanding of its distribution and magnitude. METHODS: This is a retrospective descriptive analysis conducted over a 2-year period at Linkou Chang Gung Memorial Hospital. We focused on the population of maxillofacial injury caused by motorcycle accidents. We divided the patient cohort into 3 main trauma mechanisms: single-motorcycle collision (SM group), motorcycle-to-motorcycle collision (MM group), motorcycle-to-vehicle collision (MV group). Data, including demographics, age, fracture patterns of facial bones, and other associated injuries, were collected. RESULTS: A total of 881 cases were identified that involved facial fractures. Most patients were male (71%), young adult (mean age, 32.49 years), and the most common fracture region is the midfacial fracture (79.5%, 700 victims). Among the 3 groups, the MM group was less likely to sustain severe injuries by trauma score system, less head injury and mortality rate. The MV group and SM group have similar mortality rates but different fracture pattern tendencies. Lower facial fractures were more likely in the MV group, but midface fractures in the SM group. Associated injuries were higher in the MV group. CONCLUSIONS: Our study presents the different trends of fracture patterns and injury under 3 main mechanisms of motorcycle casualties. We document all these data in the hope of providing insights into trauma doctors dealing with motorcycle accidents.

Efficacy of modified levator-muscle resection using Putterman ptosis clamp versus traditional levator-muscle resection for aponeurotic ptosis: A retrospective analysis.

BACKGROUND/OBJECTIVES: In recent years, a modified levator muscle resection using Putterman ptosis clamp was developed. We used a retrospective case-control study to compare the effects of the modified and traditional levator muscle resection methods. METHODS: Patients with moderate-to-severe ptosis who underwent the traditional or modified method for levator muscle resection were divided into two groups: Group I received the traditional method in 2013 and Group II received the modified method using Putterman clamp in 2015. During each postoperative visit, in addition to imaging, changes in the margin reflex distance 1 (MRD 1), and adverse events were recorded. Surgical time and final result in the last follow-up were recorded. RESULTS: Group I had 35 patients (54 eyes) and Group II had 33 patients (59 eyes). After the surgery, the MRD 1 in both groups was significantly improved at 1 week and at the final visit compared to baseline. Significant differences were observed in MRD 1 change at 1-week post-operation and the change at the final visit and the surgical time between Groups I and II (P < 0.05). Group II had a shorter surgical time than Group I. Compared with Group I (20.37%), the revision rate was lower in Group II (10.16%). CONCLUSIONS: The modified levator muscle resection using Putterman ptosis clamp and traditional levator muscle resection can both improve ptosis. Comparison results showed that using Putterman ptosis clamp assisted in levator muscle surgery had shorter operation time, faster postoperative recovery, and lower revision rate than the traditional method. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Risk Factors of Carpal Tunnel Syndrome in Taiwan: A Population-Based Cohort Study.

BACKGROUND: Carpal tunnel syndrome (CTS), 1 of the most common peripheral neuropathies of the upper extremity, has been studied for decades regarding its epidemiology and associated medical conditions. We conducted a large-scale, age- and gender-matched study from an Asian population database to investigate the relationship between the incidence and the demographic characteristics. METHODS: A retrospective cohort study using data of National Health Insurance Research Database was conducted. One million enrollees in Taiwan was used to identify 9442 patients with CTS and 37,768 randomly selected controls, in a control-case ratio of 4:1. Diagnoses of CTS were ascertained from January 1, 2003, to December 31, 2012. Sociodemographic and medical characteristics were evaluated to assess the correlation with CTS. RESULTS: Annual incidence of CTS was approximately 0.4% during the 10-year-period in Taiwan, with higher incidence rate in female sex and middle age of group (50-59 years). Among the medical conditions, previous wrist injuries, obesity, gout, and rheumatoid arthritis were associated with CTS most significantly. CONCLUSIONS: Carpal tunnel syndrome has presented a relatively constant incidence in Taiwan. Female gender with middle age seemed to have the highest incident rate during a 10-year period from 2003 to 2012. Among the risk factors of CTS, previous wrist injuries, obesity, gout, and rheumatoid arthritis were demonstrated to be the most significantly correlated comorbidities.

Allogeneic Bone-Marrow Mesenchymal Stem Cell with Moldable Cryogel for Craniofacial Bone Regeneration.

Allogeneic bone-marrow mesenchymal stem cells (BMSCs) can promote bone regeneration and substitute for autologous BMSCs if autologous sources are unavailable, but the efficacy of bone regeneration by allogeneic BMSCs is still inconsistent. A Lewis rat cranium defect model was used to investigate the efficacy of bone regeneration between autologous and allogeneic BMSCs in gelatin-nanohydroxyapatite cryogel scaffolds. BMSCs from Wistar rats served as the allogeneic cell lineage. The full-thickness cranium defects were treated by either blank control, cryogel only, allogeneic BMSC-seeded cryogel, or autologous BMSC-seeded cryogel (n = 5). Bone regeneration was monitored by micro-computed tomography and examined histologically at week 12. In addition, we assessed the immune responses in vitro by mixed lymphocyte reaction (MLR) assay and CD4+ immunochemistry staining ex vivo. The MLR showed that allogeneic BSMCs elicited a weak immune response on day 14 that progressively attenuated by day 28. In vivo, the bone regeneration in allogeneic BMSCs was inferior at week 4, but progressively matched the autologous BMSCs by week 12. Our results suggest that allogeneic BMSCs can serve as an alternative source for bone regeneration.

Le Fort Fractures With Maxillary Immobility: Classification and the Moment Concept to Rationalize Optimal Surgical Treatment.

BACKGROUND: Le Fort fractures with maxillary immobility are an uncommon presentation of facial trauma often associated with the disturbance of occlusion. Historically, cases involving high Le Fort fractures require a coronal extensive approach to mobilize the maxilla for occlusion restoration. Here, we review our institutional series of immobile Le Fort fractures and present their treatment approach, outcomes, classification, and then rationalize our treatment with a concept philosophy. MATERIALS AND METHODS: We treated 12 consecutive patients with unilateral and bilateral immobile Le Fort fractures from 2010 to 2017. The mean age was 27.1 years. Ten patients had a unilateral greenstick Le Fort III fracture. Five patients also had associated mandible fractures. Intraoperative occlusions could only be restored after Le Fort I osteotomy was performed on the side of the immobile Le Fort fracture. The mean follow-up period was 1.6 years. RESULTS: All patients presented good long-term occlusion restoration. There were no cases of nonunion or significant complications. None of the patients complained of any malar or periorbital cosmetic issues during follow-up sessions. CONCLUSIONS: We presented an institutional series and classification of unusual Le Fort fractures with maxillary immobility, including a previously unreported fracture configuration of greenstick unilateral Le Fort III fractures combined with complete contralateral Le Fort I fracture. Based on our moment concept to rationalize treatment, as well as a systematic review of published literature, we advocate the judicious use of Le Fort I osteotomy to efficiently and safely treat these unusual fractures.

Clinical outcome following intraoperative computed tomography-assisted secondary orbital reconstruction.

BACKGROUND: Secondary post-traumatic orbital reconstructions are challenging. Portable computed tomography (CT) provides the option to acquire real-time, intraoperative images that help to detect the insufficient reconstruction of the orbit immediately. We retrospectively analyzed patients who received intraoperative CT imaging and analyzed the effect of intraoperative CT scans on revision rates and orbital volume changes before, during, and after surgery. METHODS: From August 2014 to September 2016, eleven patients received intraoperative cone-beam CT scans to evaluate the results of secondary orbit reconstruction using Medpor + titanium implants. Patient demographics, surgical details, CT scanning protocol, and follow-up results were analyzed. 3D CT volumetry was used to analyze the orbital volume based on OsiriX MD software. RESULTS: Based on intraoperative CT findings, seven cases required intraoperative revision to further augment the orbital cavity or adjust implants. The mean preoperative measured enophthalmos was 3.41±1.4 mm (range: 2-6 mm), which decreased to 0.73±0.4 mm (range: 0-1 mm) at postop assessment (p<0.0001). On the fracture side, there was a significant difference between preoperative vs. intraoperative and preoperative vs. postoperative volume measurements (p<0.01 for both subsets), but no significant difference between intraoperative vs. postoperative measurements. CONCLUSION: Intraoperative CT is a valuable tool in secondary orbital reconstruction cases based on clinical enophthalmos evaluation and 3D CT volumetry. For these patients, the avoidance of another revision surgery may outweigh the disadvantage of increased operation time and additional radiation exposure.

Surgical Decompression or Corticosteroid Treatment of Indirect Traumatic Optic Neuropathy: A Randomized Controlled Trial.

BACKGROUND: Traumatic optic neuropathy (TON) is a rare cause of severe permanent visual impairment after injury. Traumatic optic neuropathy may occur due to sharp trauma (direct injury) that damages the optic nerve directly or due to damage from the transmitted forces after a concussive blow to the head or orbit (indirect injury). The management of indirect TON remains controversial. Either surgical decompression or mega dose corticosteroid is used for managing indirect TON. However, no consensus exists regarding the definitive treatment. MATERIALS AND METHODS: We designed a randomized controlled trial study to investigate this issue. Only patients with indirect TON and normal vision before the injury were enrolled. The patients' data were recorded, and fine cut facial computed tomography scan was performed to exclude those with retrobulbar hematoma. All the study subjects were randomly allocated to either the mega dose steroid (30 mg/kg stat and 15 mg/kg every 6 hours for 3 days) group or the surgical decompression group. The patients were followed up at 1 week, 1 month, 3 months, 6 months, and 9 months. During each follow-up, the Snellen visual acuity (VA), visual field, color change, fundus findings, and intraocular pressure were evaluated. These data were compared and analyzed using the Mann-Whitney U test and odds ratio. The short form questionnaire was used to analyze the lift quality difference between the two groups. RESULTS: Thirty patients were enrolled, 12 in the surgical group and 18 in the steroid treatment group. There were no significant differences in the improvement rate, improvement degree, and life quality between the groups. However, the odds ratios are 5, 10, 2.5, and nonavailable in the cutoff points of no light perception (NLP), light perception (LP), hand movement, and counting finger in surgery group. In steroid group, they are 1, 1, 1, 1.83 in each cutoff points. Patients with better VA than NLP had better life quality than those with NLP VA (P = 0.005). Other cutoff point groups had no significant difference. CONCLUSIONS: Patients with worse initial VA (eg, NLP and LP) had a higher chance of benefiting from surgical treatment and experiencing improvements in the life quality.

Ibuprofen-Loaded Hyaluronic Acid Nanofibrous Membranes for Prevention of Postoperative Tendon Adhesion through Reduction of Inflammation.

A desirable multi-functional nanofibrous membrane (NFM) for prevention of postoperative tendon adhesion should be endowed with abilities to prevent fibroblast attachment and penetration and exert anti-inflammation effects. To meet this need, hyaluronic acid (HA)/ibuprofen (IBU) (HAI) NFMs were prepared by electrospinning, followed by dual ionic crosslinking with FeCl3 (HAIF NFMs) and covalent crosslinking with 1,4-butanediol diglycidyl ether (BDDE) to produce HAIFB NFMs. It is expected that the multi-functional NFMs will act as a physical barrier to prevent fibroblast penetration, HA will reduce fibroblast attachment and impart a lubrication effect for tendon gliding, while IBU will function as an anti-inflammation drug. For this purpose, we successfully fabricated HAIFB NFMs containing 20% (HAI20FB), 30% (HAI30FB), and 40% (HAI40FB) IBU and characterized their physico-chemical properties by scanning electron microscopy, Fourier transformed infrared spectroscopy, thermal gravimetric analysis, and mechanical testing. In vitro cell culture studies revealed that all NFMs except HAI40FB possessed excellent effects in preventing fibroblast attachment and penetration while preserving high biocompatibility without influencing cell proliferation. Although showing significant improvement in mechanical properties over other NFMs, the HAI40FB NFM exhibited cytotoxicity towards fibroblasts due to the higher percentage and concentration of IBU released form the membrane. In vivo studies in a rabbit flexor tendon rupture model demonstrated the efficacy of IBU-loaded NFMs (HAI30FB) over Seprafilm® and NFMs without IBU (HAFB) in reducing local inflammation and preventing tendon adhesion based on gross observation, histological analyses, and biomechanical functional assays. We concluded that an HAI30FB NFM will act as a multi-functional barrier membrane to prevent peritendinous adhesion after tendon surgery.

Osteogenic potential of induced pluripotent stem cells from human adipose-derived stem cells.

BACKGROUND: Bone regeneration is a crucial and challenging issue in clinical practice. Bone tissue engineering (BTE) with an optimal cell source may provide an ideal strategy for the reconstruction of bone defects. This study examined whether induced pluripotent stem cells (iPSCs) derived from adipose-derived stem cells (ASCs) could act as an osteogenic substitute and whether these ASC-iPSCs yield more new bone formation than ASCs in hydrogel scaffolds. METHODS: ASC-iPSCs were reprogrammed from ASCs through a retroviral system. ASCs were harvested and isolated from adipose tissue of humans. An aliquot of cell suspension (1 × 106 cells/mL) was seeded directly onto the nHAP-gelatin cryogel scaffolds. Nude mice back implantation of cell-seeded scaffolds was designed for in vivo comparison of osteogenic potentials between ASCs and ASC-iPSCs. Samples were harvested 4 and 8 weeks after implantation for further analysis based on histology and RT-PCR. RESULTS: ASC-iPSCs were successfully obtained from human adipose-derived stem cells. PCR results also showed that specific genes of iPSCs with the ability to cause the differentiation of cells into the three germ layers were expressed. In our in vivo experiments, iPSCs were subcutaneously injected into nude mice to induce teratoma formation. The morphology of the three germ layers was confirmed by histological staining. ASC is an essential cell source for BTE with benefits of high volume and less-invasive acquisition. With additional transforming Yamanaka factors, ASC-iPSCs showed higher osteogenic differentiation and elevated expression of collagen type I (Col I), osteocalcin (OCN), alkaline phosphate (ALP), and runt-related transcription factor 2 (RunX-2). CONCLUSIONS: This report suggests that ASC-iPSCs could be a superior cell source in BTE with better osteogenic differentiation efficacy for future clinical applications.

Application of Computer-Assisted Navigation System in Acute Zygomatic Fractures.

OBJECTIVE: To compare the surgical results of early treatment of zygomatic fractures with and without the use of the computer-assisted navigation system. METHODS: All patients with unilateral traumatic zygomatic fractures treated within 30 days after the injury at a single center between June 2012 and May 2017 were studied retrospectively. Primary outcome was defined by the displacement at 5 junctional sutures of zygomatic bone, the change at each point before and after the reconstruction, and the patient's subjective scoring of their appearance. Secondary outcome included the length of the operation and hospital stay, the number of incisional approaches, the fixation points, the maximal mouth opening, and the sequelae upon follow-up. RESULTS: Twenty-eight patients were enrolled in this study. Fourteen of them received surgery with the help of a computer-assisted navigation system (navigation group), and 14 patients were treated without its assistance (control group). Before the surgery, the mean displacement of each junctional suture and the mean total displacement between both groups were comparable. Postoperative computed tomography showed that the mean total displacement was significantly less for the navigation group than the control group (0.53 vs 2.93 mm, P = 0.001), and the displacement of zygomaticosphenoid suture was smaller (0 vs 0.9 mm, P = 0.009). Patients in the navigation group underwent surgery via the single buccal-gingival approach without the need for longer operation time. There were no significant differences in the length of hospital stay, maximal mouth opening, or cheek numbness. All patients recovered without major complications and were comparatively satisfied with their final appearance. CONCLUSIONS: The navigation system has been demonstrated to be a useful tool for improving the symmetry in delayed or secondary reconstruction of zygomatic fractures. This study showed its effectiveness and safety in cases of early treatment as well, achieving a more accurate correction in a less invasive manner.

Maxillofacial Fractures Associated With Laryngeal Injury: A Craniofacial Surgeon Should be Alert.

OBJECTIVE: Maxillofacial fractures with concomitant laryngeal injuries put both the quality and maintenance of life in jeopardy. Because of its low incidence, it is often overlooked in the clinical setting. The purpose of this study is to review the incidence, clinical presentations, managements, and outcomes of these patients. METHODS: A retrospective analysis of medical records from 2008 to 2015 was conducted at a single institute. A case series (n = 12, which contributed 22.2% of laryngeal injuries in our institute) of these patients was presented, and propensity score matching was applied for further statistical analysis. RESULTS: When comparing patients who sustained maxillofacial fractures with concomitant laryngeal injuries with patients with only maxillofacial fractures and no laryngeal injuries, subcutaneous emphysema (83.3% vs 4.2%, P < 0.001), neck pain (75.0% vs 6.3%, P < 0.001), dyspnea (75.0% vs 0%, P < 0.001), hoarseness (41.7% vs 0%, P < 0.001), neck swelling (66.7% vs 4.2%, P = 0.012), stridor (16.7% vs 0%, P = 0.037), hemoptysis (16.7% vs 0%, P = 0.037), and thoracic trauma (58.3% vs 10.4%, P = 0.001) all showed significant differences. The length of intensive care unit stay (7.42 days vs 3.21 days, P = 0.008), ventilator use (66.7% vs 18.8%, P = 0.002), and tracheostomy (58.3% vs 0%, P < 0.001) were also significantly different. CONCLUSIONS: A significant portion of laryngeal injuries is concurrent with maxillofacial fractures. As a craniofacial surgeon, we should be alert to the signs of laryngeal injury. Diagnosis of laryngeal injuries should be established before definitive surgery for maxillofacial fractures.

Dissolving Microneedle Patches for Transdermal Insulin Delivery in Diabetic Mice: Potential for Clinical Applications.

In this study, dissolving polymeric microneedle (MN) patches composed of gelatin and sodium carboxymethyl cellulose (CMC) were used to localize insulin. Their in vitro skin insertion capabilities were determined using tissue-marking dye to stain the skin after patches removal. Scanning electron microscopy (SEM) was used to determine changes in the MNs over time, and optical coherence tomography (OCT) was used to monitor their real-time penetration depth. Confocal microscopy images revealed that rhodamine 6G gradually diffuses from the puncture sites to deeper dermal tissue. Using an in vivo imaging system (IVIS), skin areas that received FITC-insulin-loaded MNs were found to present strong fluorescent signals that greatly decreased 1 h after application. Results show that dissolving MNs rapidly release FITC-insulin, and it then gradually diffuses into the skin. This study verifies that using a gelatin/CMC MN patch for insulin delivery achieves satisfactory relative bioavailability compared to a traditional hypodermic injection and can be a promising delivery device for poorly permeable protein drugs such as those used to treat diabetes. Insertion tests on human cadaveric skin demonstrate that dissolving MNs could serve as efficient devices for transdermal drug delivery in clinical practice and that the volar aspect of forearm skin is the ideal location for their applications.

A novel anatomical thin titanium mesh plate with patient-matched bending technique for orbital floor reconstruction.

This study developed an anatomical thin titanium mesh (ATTM) plate for Asian orbital floor fracture based on the medical image database. The computer aided stamping analysis was performed on four hole/slot patterns included the control type without hole design, circular hole pattern, slot pattern and hole/slot hybrid patterns within the ATTM plate with upper/lower dies of averaged orbital cavity reconstruction models. The curved-fan ATTM plate with 0.4 mm thickness was manufactured and pre-bent using a patient matched stamping process to verify its feasibility and the interfacial fitness between the plate and bone on the orbital floor fracture model. The stamping analysis found that the hole/slot hybrid patterns design resulted in the most favorable performance among all designs owing to the lowest maximum von-Mises stress/strain and spring-back value. The interfacial adaption results test showed that the average patient-matched stamping bending gap size was only 0.821 mm and the operative time was about 8 s. This study concluded that the curved-fan ATTM plate with hole/slot hybrid pattern design and patient-matched pre-bent technique can fit the ATTM plate/orbital cavity interface well, decrease unstable fracture segment mobility and improve the overall reduction efficiency.

An osteopenic/osteoporotic phenotype delays alveolar bone repair.

Aging is associated with a function decline in tissue homeostasis and tissue repair. Aging is also associated with an increased incidence in osteopenia and osteoporosis, but whether these low bone mass diseases are a risk factor for delayed bone healing still remains controversial. Addressing this question is of direct clinical relevance for dental patients, since most implants are performed in older patients who are at risk of developing low bone mass conditions. The objective of this study was to assess how an osteopenic/osteoporotic phenotype affected the rate of new alveolar bone formation. Using an ovariectomized (OVX) rat model, the rates of tooth extraction socket and osteotomy healing were compared with age-matched controls. Imaging, along with molecular, cellular, and histologic analyses, demonstrated that OVX produced an overt osteoporotic phenotype in long bones, but only a subtle phenotype in alveolar bone. Nonetheless, the OVX group demonstrated significantly slower alveolar bone healing in both the extraction socket, and in the osteotomy produced in a healed extraction site. Most notably, osteotomy site preparation created a dramatically wider zone of dying and dead osteocytes in the OVX group, which was coupled with more extensive bone remodeling and a delay in the differentiation of osteoblasts. Collectively, these analyses demonstrate that the emergence of an osteoporotic phenotype delays new alveolar bone formation.

Surgical treatment of isolated zygomatic fracture: Outcome comparison between titanium plate and bioabsorbable plate.

BACKGROUND: Zygoma fracture is of clinical importance because malar prominence plays an essential role in facial appearance. Traditionally, most maxillofacial surgeons perform osteosynthesis with titanium plates and screws for rigid fixation. However, this procedure has certain disadvantages that include the possibility of implant exposure, palpability or loosening of the screws, painful irritation, temperature sensitization, and radiographic artifacts. In this study, we compared the function and satisfaction outcome between Bonamates® bioabsorbable implant and Leibinger titanium implant. METHOD: Consecutively 53 patients with isolated unilateral zygomatic fracture that were treated with the Bonamates® bioabsorbable plate system, n = 53 were compared to patients with the titanium plate system, n = 55 in the period between 2009 and 2013. All patients were followed-up at least 6 months. Preoperative and postoperative facial computed tomography (CT) scans were performed and scored from 0 to 2 in the 5 areas of zygoma. A score of 2 indicated the most severely displaced fracture in one of the areas. A visual analogue scale ranging from 0 to 10 was used to assess the postoperative aesthetic and functional satisfactions. RESULT: The mean ages of the patients in the bioabsorbable and titanium plate groups were 33 years and 30 years, respectively. The male to female ratios were 1.2:1 (bioabsorbable plate group) and 1.1:1 (titanium plate group). The average preoperative CT scan scores of the bioabsorbable and titanium plate groups were 5.7 and 5.1, respectively. The postoperative CT scan scores of the bioabsorbable and titanium plate groups were 1.3 and 1.1, respectively. The implant cost of the bioabsorbable group was approximately 6-fold higher than that of the titanium plate group. The complication rate was similar in both groups and included complications such as palpable implant, skin irritation, and hypersensitive cheek. The patients in both groups attained similar mouth-opening function and a satisfactory score at 6 months after operation. CONCLUSION: This study revealed that the bioabsorbable plate outcome was similar to the titanium plate outcome for patients with isolated unilateral zygomatic fracture. The bioabsorbable implant system provides another option for internal fixation devices in the treatment of zygomatic fractures and avoids implant removal surgery; however, the implant cost of bioabsorbable plates is higher than that of titanium plates in Taiwan.