Titanium Screws Research Articles

Prevention of complications after the surgical treatment of the facial fractures

In modern society, with a high rate of industrialization and, at the same time, a decrease in the standard of living, an increase in maxillofacial injury (MFI) has been noted, ranging from 6 to 16% of the total number of injuries. In addition, MFI is a public health problem due to its high prevalence and the need for resources to treat it, as well as the financial and social impact of MFI victims on the health care system. Osteosynthesis of the bones of the facial skeleton with titanium miniplates and screws is an effective way to treat fractures of the bones of the facial skull. According to the studied literature sources, researchers continue to search for the most inert materials for surgical otheosynthesis. Samples of various materials are examined for the adhesive ability of the main pathogens of purulent-inflammatory diseases, inertness, toxicity and other indicators. But studies are few and there is no conclusive evidence in favor of either material. However, the use of titanium miniplates and screws coated with silicon carbide is advisable for the prevention of postoperative complications. The use of titanium miniplates and screws coated with silicon carbide is the method of choice in the treatment of infected fractures of the bones of the facial skeleton.

Finite Element Analysis for First Metatarsophalangeal Joint Arthrodesis Demonstrates Reduction in Stress Across Bio-Integrative Fixation Over Traditional Metal Fixation

Category: Midfoot/Forefoot; Bunion Introduction/Purpose: During each step-in gait, the first metatarsophalangeal joint (MTPJ) is stressed by 90% of body weight, while loading the metatarsal head and base with up to 29% (228N/80Kg patient) of body weight (188N) during each foot push-off. To withstand these high mechanical forces, a successful fusion is dependent on joint preparation and rigid fixation. In this study we assessed a novel bio-integrative fiber-reinforced screw and nail construct. This material technology may provide improved mechanical fixation profile through its high flexural strength and flexural modulus that is closely matched to that of cortical bone. Finite Element Analysis (FEA) was performed to evaluate the mechanical strength and stress concentrations acting on the 1st MTPJ fusion following the use of these implants, compared to conventional metal fixation. Methods: CT-based FEA of the 1st MTPJ fusion fixed by two fixation methods was simulated for mechanical strength and stress concentrations acting on the surrounding cortical bone. The 1st MTPJ of an adult male weighing 80kg was segmented from a left foot CT scan (120 KVP, SL 1mm) and was incorporated in a 3-dimensional CAD model. Bio-integrative fiber-reinforced 4.0mm partially threaded headless compression screw, and a 3.0mm fiber-reinforced cannulated nail were inserted in this computational model in crossed fashion (Fig. 1A). The bio-integrative implants are composed of continuous reinforcing mineral fibers (50% w/w), comprised of elements found in native bone and bound together by a degradable polymer [poly (L-lactide-co- D,L-lactide), PLDLA]. Two 4.0mm partially threaded headless titanium screws were inserted in similar trajectories and served as control (Fig. 1B). The FEA algorithm was based on published known forces acting on the first ray during push-off. Post-processing was performed on FEA results. Results: The relative displacement between the Metatarsal and Phalangeal heads upon simulated loading was 1.6mm for metal fixation and 0.2mm for the fiber-reinforced bio-integrative fixation, demonstrating this technology to be mechanically stable at least as conventional metal fixation. In both models, the Von-Mises maximum stresses were found between the implant thread and shank. However, maximum localized stresses in cortical bone regions interacting with the metal implants were substantially higher (up to 8 times) compared to the bio-integrative implant-bone interactions. Moreover, stresses in the implant body were remarkably higher with metal implants compared to bio-integrative fixation (Fig. 1C, D&E). These results indicate that for physiological loading conditions applied on the 1st MTPJ, the use of bio-integrative fixation construct may reduce stress concentrations at the implant-cortical bone interface. Conclusion: FEA results indicate that bio-integrative screw-nail construct provides equivalent mechanical fixation strength to metal fixation, while resulting in lower bone-implant stress concentrations. The closely matched flexural modulus of the bio- integrative material to that of cortical bone, decreases implant-bone resistance level and the probability of bone/implant failure and risk for implant loosening, all common complications in foot and ankle surgery. This study demonstrates a new methodology of CT-FEA for the evaluation of 1st MTPJ fusion arthrodesis and suggests the bio-integrative screw-nail combination as an alternative to traditional metal fixation. This model is currently being investigated in an ongoing clinical series.

Titanium Implants in the Nose: State of the Art.

Titanium implants in the head have been used widely for decades. Dental implants as well as titanium plates, screws, and mesh have been an integral part of dental and maxillofacial surgery. In the nose, titanium implants were started in 2003. Their purpose is to increase structure and stiffness to nasal cartilages widening the airway. This overview describes the use of titanium implants in the various locations in the nose. We concentrate on three locations: Breathe Implants on the upper lateral cartilage to widen the internal nasal valve, modified breathe implants in the lower lateral nasal wall fixed to the piriform aperture as batten grafts to widen the external nasal valve, and flattened breathe implants as titanium septum plates to straighten and strengthen the nasal septum.

Effect of gastrodin on bone tissue around implants in type 2 diabetic rats

Objective: To study the effect of gastrodin on oxidative stress and bone tissue around implants in type 2 diabetes mellitus rats (T2DM), so as to provide therapeutic basis for the problems of poor osseointegration and long repair period of implants in type 2 diabetic patients, to provide the basis for the development of new therapeutic drugs. Methods: Forty SD rats aged 5 weeks were divided into control group (n=10) and model group (n=30). The model group was fed with high glycolipid diet for 4 weeks and injected with 35 mg/kg streptozocin. The T2DM were divided into diabetic group (n=10) and gastrodin group (n=10). Pure screw titanium implants were placed in the metaphysis of both tibia. Rats in gastrodin group were given gastrodin 13.6 mg/kg everyday, while the control group and diabetic group were given the same dose of saline solution. Blood glucose was measured every two weeks after operation in all rats. After 4 and 8 weeks, the contents of serum malondialdehyde (MDA) and superoxide dismutase (SOD) were measured to analyze the oxidative stress level in rats. The expression of anti-apoptosis protein [B cell lymphoma/lewkmia-2 (bcl-2)]and apoptosis protein [bcl-2-associated X protein (bax)] was analyzed by immunohistochemistry. HE staining and micro-CT scanning were used to analyze the osseointegration around the implants. Results: The blood glucose of gastrodin [(12.98±2.53), (13.64±1.96), (14.58±3.40) and (12.84±2.82) mmol/L] were significantly lower than that of diabetic group [(20.97±2.27), (17.94±3.76), (23.66±2.90) and (21.22±2.67) mmol/L] at corresponding time point (P<0.017). Four and 8 weeks following surgery, the MDA concentration in gastrodin group [(5.21±1.60) and (3.47±1.17) nmol/ml] was significantly lower than that in diabetic group [(11.42±5.11) and (7.31±1.37) nmol/ml] at the corresponding time points (P<0.017), while SOD activity in gastrodin group [(42.89±6.00) and (53.12±9.73) U/ml] was significantly higher than those in diabetic group [(27.09±6.11) and (32.08±2.97) U/ml] at the corresponding time points (P<0.017). Immunohistochemistry showed that the bcl-2 expression in gastrodin group was significantly higher than that in diabetic group at 4 and 8 weeks following surgery (P<0.017), while the bax expression in gastrodin group was significantly lower than that in diabetic group (P<0.017). Four weeks after surgery, the bone volume/tissue volume (BV/TV), connection density (Conn.D), trabecular number (Tb.N), trabecular thickness (Tb.Th) in gastrodin group were significantly higher than those in diabetic group (P<0.017). There was no significant difference in trabecular separation/spacing (Tb.sp) between gastrodin group and diabetic group (P<0.017). Eight weeks after surgery, the BV/TV, Tb.N in gastrodin group were significantly higher than those in the diabetic group (P<0.017). There was no significant difference in Conn.D between gastrodin group and diabetic group (P<0.017). There was no significant difference in Tb.Th and Tb.sp in three groups (P<0.017). The trabecular structure in gastrodin group was better than that in diabetic group by HE staining. Conclusions: Gastrodin can decrease blood glucose, improve oxidative stress, protect bone tissue from apoptosis and promote bone formation around implants in T2DM.

Is Heterotopic Ossification Removal From Alloplastic Temporomandibular Joint Prosthesis Using Er,Cr:YSGG Laser Superior to Conventional Methods?

Heterotopic ossification (HO) formed over the major components and fixation screw heads of an alloplastic temporomandibular joint replacement (TMJR) prosthesis can result in decreased quality of life, limited function, prosthesis failure, and hinder prosthesis revision, replacement, or removal. This study simulated HO removal from the major components and fixation screw heads of alloplastic TMJR prostheses using an erbium, chromium-doped yttrium, scandium, gallium, and garnet (Er,Cr:YSGG) laser and compared the results to conventional methods of HO removal. The surface morphology and chemical structure of the exposed components were analyzed. The investigators hypothesize that HO removal with an Er,Cr:YSGG laser causes less damage to TMJR prosthesis components compared to conventional HO removal methods. This multiple test descriptive analysis simulated HO removal from TMJR prostheses mounted to stereolithic models. Simulated HO removal was completed using a novel Er,Cr:YSGG laser method and conventional methods which utilized a fissure carbide bur in a high-speed rotary instrument, a standard osteotome, and an ultrasonic aspirator. Surfaces exposed on the TMJR prostheses were analyzed for morphological or chemical change using scanning electron microscopy, energy dispersive X-ray spectroscopy, and Raman spectroscopy. The Er,Cr:YSGG laser did not adversely affect the titanium screws or titanium components of the TMJR prostheses, while conventional methods of HO removal did. HO removal using the Er,Cr:YSGG laser and conventional methods both inflicted surface damage to the fossa ultrahigh molecular weight polyethylene component of the TMJR prostheses. Damage inflicted to titanium alloy or commercially pure titanium components of TMJR prostheses by conventional HO removal methods can be avoided by instead removing HO with an Er,Cr:YSGG laser. However, long exposure of the Er,Cr:YSGG laser to ultrahigh molecular weight polyethylene surfaces should be avoided. Additional research to expand on applications to other procedures and in other surgical fields is encouraged.

Deformation of implant retaining screws-Study with stereoscopic microscopy and microCT.

The prosthetic screw fixes the prostheses to the implants. Upon osteointegration, the untightening of the prosthetic screw is the most common problem in oral rehabilitation with implants. To study the deformation of the implant retaining hexagonal screw head. This investigation used two methods for evaluating the screw head's area of deformation (mm2 ): a stereoscopic microscopy and micro computed tomography (microCT). For stereoscopic microscopy, 16 titanium alloy (T) and 16 titanium gold-plated alloy (G) screws of the Zimmer Biomet™ brand were used, divided into eight groups: group 0 (control group), groups T1 and G1 (screws tightened 10 times to 20 Ncm), the groups T2 and G2 (screws tightened 20 times to 20 Ncm) and the groups T3 and G3 (screws tightened 10 times to 30 Ncm). In the study with microCT, one screw was randomly chosen from each of the groups described above to perform the scanning by microCT. When comparing the type of screw material using stereoscopic microscopy, no statistically significant differences were found (p > 0.05). Contrarily, different number of successive grips and different torque value showed statistically significant differences in the head section of the retaining screws (p < 0.05). The observation by microCT showed the torque applied is crucial to the head deformation in titanium screws. In gold-plated screws the successive tightening appears to be pivotal. Titanium and gold screws tend to behave similarly. By increasing the tightening cycles and the torque values of protocols greater levels of deformations can be expected. In general, microCT data showed better results for gold-plated titanium alloy. To control severe screw head deformation and the impossibility of untightening the implant's restoration, clinicians should avoid extreme torque values and prevent surpassing 10 tightening cycles.

Hardware Removal in Orthognathic Surgery Patients: A 20 Year Retrospective Study

In the United States, the standard of care for rigid fixation in orthognathic surgery is titanium plates and screws. This hardware is meant to remain implanted indefinitely, but the potential for hardware removal is always mentioned in preoperative discussions. The incidence of titanium hardware removal after orthognathic surgery has been reported to range from 0.4% to 27%, and the largest study previously published included 570 patients over 5 years.1,2 The purpose of this study is to examine the incidence of titanium hardware removal after orthognathic surgery over a 20-year period and to identify factors associated with removal. A retrospective study was performed involving subjects who underwent orthognathic surgery including a combination of Le Fort osteotomy, bilateral sagittal split osteotomy, genioplasty, subapical osteotomy, and vertical ramus osteotomy. The primary outcome variable was titanium hardware removal. Other predictor variables included age, sex, simultaneous removal of third molars, simultaneous bone grafting, and medical comorbidities. Patients met inclusion criteria if they had undergone orthognathic surgery with titanium fixation at a single institution by a single surgeon between the years of 2000 and 2020. Patients with cleft and craniofacial syndromes and those fixated with resorbable hardware were excluded. A total of 738 patients met inclusion criteria with 1,483 orthognathic surgery procedures performed. The mean age at the time of surgery was 23.2 years, and 57% of subjects were female. Ultimately, 43 of the 738 patients required hardware removal (5.8% of patients), and 48 of the 1,483 procedures resulted in hardware removal (3.4%). The average time to hardware removal was 2.3 years (ranging 6 weeks to 9.7 years) with a median of 1.3 years. The most common indication for removal was surgical site infection (17 patients), followed by palpable, painful hardware (12 patients), exposed hardware (6 patients), maxillary sinusitis (4 patients), adjacent tooth external root resorption (1 patient), loose hardware (1 patient), prophylactic removal after previous infection (1 patient), and thermal sensitivity (1 patient). Patients who required hardware removal were more often female (69.8%), were older (average 29.9 years), and were more likely to have multiple jaws operated (79.1%). Of the 43 patients with hardware removed, 19 had hardware removed from the mandible (44.2%), 18 from the maxilla (41.9%), 2 from the genioplasty (4.6%), and the remainder had multiple sites removed (9.3%). The laterality of hardware-associated symptoms was more often right-sided (51.1%) than left-sided (39.5%), and bilateral symptoms were less common (9.3%). A history of obstructive sleep apnea was documented in 9.3% of patients with hardware removed, as compared to 4.5% of the general population of orthognathic surgery patients. The population of patients with cleft and craniofacial syndromes was examined separately, and the rate of removal in this population of 121 patients was slightly lower than that of the general population (5%). The incidence of titanium hardware removal in this population of orthognathic surgery patients was 5.8%. Our findings suggest that there are patient-specific and procedure-specific factors associated with increased rates of titanium hardware removal after orthognathic surgery. Based on descriptive and multivariate analyses, higher risk groups include female patients, older patients, patients with obstructive sleep apnea, and patients in whom multiple jaws are operated. These patients may be counseled accordingly about the risk of future hardware removal.

Juxtametallic Bipolar Bone Radiofrequency Ablation: Thermal Monitoring in an Ex-Vivo Model with Specimen MRI and Histopathologic Correlation

PurposeTo measure the ablation zone temperature and nontarget tissue temperature during radiofrequency (RF) ablation in bone containing metal instrumentation versus no metal instrumentation (control group). Materials and MethodsEx vivo experiments were performed on 15 swine vertebrae (control, n = 5; titanium screw, n = 5; stainless steel screw, n = 5). Screws and RF ablation probe were inserted identically under fluoroscopy. During RF ablation (3 W, 5 minutes), temperature was measured 10 mm from RF ablation centerpoint and in muscle contacting the screw. Magnetic resonance (MR) imaging, gross pathologic, and histopathologic analyses were performed on 1 specimen from each group. ResultsAblation zone temperatures at 2.5 and 5 minutes increased by 12.2 °C ± 2.6 °C and 21.5 °C ± 2.1 °C (control); 11.0 °C ± 4.1 °C and 20.0 °C ± 2.9 °C (juxta-titanium screw), and 10.0 °C ± 3.4 °C and 17.2 °C ± 3.5 °C (juxta–stainless steel) screw; differences among groups did not reach significance by analysis of variance (P = .87). Mixed-effects linear regression revealed a statistically significant increase in temperature over time in all 3 groups (4.2 °C/min ± 0.4 °C/min, P < .001). Compared with the control, there was no significant difference in the temperature change over time for titanium (−0.3 °C/min ± 0.5 °C/min, P = .53) or steel groups (−0.4 °C/min ± 0.5 °C/min, P = .38). The mean screw temperature at the final time point did not show a statistically significant change compared with baseline in either the titanium group (−1.2 °C ± 2.3 °C, P = .50) or steel group (2.6 °C ± 2.9 °C, P = .11). MR imaging and pathologic analyses revealed homogeneous ablation without sparing of the peri-hardware zones. ConclusionsAdjacent metallic instrumentation did not affect the rate of or absolute increase in temperature in the ablation zone, did not create peri–metallic ablation inhomogeneities, and did not result in significant nontarget heating of muscle tissue in contact with the metal instrumentation.

34. The effect of screw length on single-level anterior cervical fusion using finite element

<h3>BACKGROUND CONTEXT</h3> Anterior cervical discectomy fusion and plating (ACDFP) is one of the most common neurosurgical procedures performed. Early in the use of plates to minimize postoperative orthosis duration and to increase healing rates, there was an attempt to use a bicortical screw purchase. Over time, we have typically converted to a lesser screw length to decrease any additional risks from the bicortical technique. Our study looks at the biomechanical effect of screw length at a single-level ACDFP and the effect on adjacent levels in flexion and extension using finite element modeling. <h3>PURPOSE</h3> To determine the effect of screw length on single-level anterior cervical discectomy, fusion and plating, and its clinical application. <h3>STUDY DESIGN/SETTING</h3> Finite element model. <h3>METHODS</h3> A previously validated three-dimensional osteoligamentous finite element model (FEM) of the cervical spine column (C2-T1) was used. The FEM simulated the vertebra of the body, posterior elements, intervertebral disc and ligaments. Each vertebral body consisted of a thin cortical shell, a softer cancellous bone, endplate, and a posterior bony structure. The cortical bone was modeled as a linear isotropic material of 0.5mm thick shell surrounding the cancellous bone and a 0.2mm thick endplate was placed on the superior and inferior surface of the intervertebral disc. Each single motion segment of the FEM consists of vertebral bodies, intervertebral disc and five major vertebral ligaments. The intervertebral disc was modeled and composed of the nucleus pulposus, annulus ground substance and annulus fibrosus. Material property parameters from literature were used as definitions in the model. The intact spine was modified at the C5-C6 functional spine unit level to simulate the biomechanics of ACDF with different screw lengths (12mm, 14mm, 16mm, 18mm). The standard surgical procedure was used to simulate ACDFP with different length screws at the C5-C6 level. The ALL was removed. The disc properties were altered at the surgical level to simulate the trabecular bone, and this represented complete fusion. The plate was placed at the C5-C6 level, and 4 titanium screws were simulated. All FEM were fixed at the first thoracic vertebra in all degrees of freedom, and load was applied at the C2 superior endplate vertebra. Bending moment (1.5 Nm) combined with a follower load (75N) magnitude under flexion and extension was applied to the intact model. The ROM was measured at each level and across the C3-C7 levels. The variable moment loading protocol (otherwise known as hybrid loading) was next applied. The bending moment was varied until the ACDF with different length screw models displayed the same total range of motion across the C3-C7 levels (although individual segments could have different range of motion). The ROM was obtained at the segmental levels under the same loading mode. <h3>RESULTS</h3> The C5-6 area of fusion demonstrated the least flexion (0.17°) and extension (0.36°) with the 18mm screw and the most flexion (0.75°) and extension (1.06°) with the 12 mm screws. The length of the screw effects the adjacent levels of the spine throughout with the largest increase in ROM in flexion (11.51° -11.98° with 12mm and 18mm screw length respectively) and extension (6.71°- 7.71° with 12mm and 18mm screw length respectively occurring at the cephalad C4-5 level. The caudal C6-7 adjacent level was more pronounced with an increase in flexion ROM with 12mm screws with 12.04° vs 11.88° with 18mm screws and increased but less pronounced ROM in extension with 6.34° with 18mm screws and 5.72° with 12mm screws. <h3>CONCLUSIONS</h3> Increased screw length results in higher flexion ROM at the C4-5 level. An inverse relationship is noted with 12mm screws at the C6-7 adjacent levels demonstrating more ROM than the 18mm screws in flexion. In extension both C4-5 and C6-7 demonstrate that increasing screw length results in increased ROM as compared to 12mm screws. This increased ROM would be expected to increase adjacent segment degeneration more prominently at the C4-5 level as compared to C6-7. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

Locally delivered antistaphylococcal lysin exebacase or CF-296 is active in methicillin-resistant Staphylococcus aureus implant-associated osteomyelitis.

Introduction: Staphylococcus aureus is the most common cause of orthopedic infections and can be challenging to treat, especially in the presence of a foreign body. The antistaphylococcal lysins exebacase and CF-296 have rapid bactericidal activity, a low propensity for resistance development, and synergize with some antibiotics. Methods: Rabbit implant-associated osteomyelitis was induced by drilling into the medial tibia followed by locally delivering exebacase, CF-296, or lysin carrier. A titanium screw colonized with methicillin-resistant S. aureus (MRSA) IDRL-6169 was inserted. Intravenous daptomycin or saline was administered and continued daily for 4 d. On day 5, rabbits were euthanized, and the tibiae and implants were collected for culture. Results were reported as log colony forming units (cfu) per gram of bone or log cfu per implant, and comparisons among the six groups were performed using the Wilcoxon rank sum test. Results: Based on implant and bone cultures, all treatments resulted in significantly lower bacterial counts than those of controls (). Exebacase alone or with daptomycin as well as CF-296 with daptomycin were more active than daptomycin alone () or CF-296 alone () based on implant cultures. CF-296 with daptomycin was more active than either CF-296 alone () or daptomycin alone () based on bone cultures. Conclusion: Local delivery of either exebacase or CF-296 offers a promising complement to conventional antibiotics in implant-associated infections.

APOPHYSEAL AVULSION FRACTURES OF ANTERIOR INFERIOR ILIAC SPINE

We aim to present diagnostic approach and results from surgical treatment in avulsion fractures of the apophysis of Spina Iliaca Anterior Inferior (SIAI).&#x0D; Material and methods. During the period 2011 – 2021, seven(7) children with acute traumatic apophysiolysis of SIAI, were operated on, 61 A1.2 fracture by AO/OTA classification. All of the patients are boys with average age 14,1±1,35 years. In all cases the right SIAI is affected and the mechanism of the injury is sports trauma. The diagnostic methods used by us are complete orthopedic clinical examination, AP radiographs of the pelvis and lateral radiographic projections of the hip joint by modified Dunlap technique and also CT scan with 3D reconstruction of the pelvic bones (3cases). In four (4) cases the apophysiolyses are Salter-Harris type I and in three cases – SH type II. The average size of the avulsed bone fragment is 3cm/1cm measured on CT scan and 29,66±3,14 mm on AP radiographic view. Dislocation of the fractured fragment is greater than 1,5cm. In four children the diagnosis from the outpatient care is neglected or primary wrong. This fact procrastinated the treatment for between 15 and 30 days. In the rest of the cases the treatment is prompt in an urgent matter. For all patients open reduction and internal fixation with screw osteosynthesis is performed by using one (4 cases) or two (2 cases) 3,5mm cannulated titanium screws. Consolidation of the fracture and the functional condition by Lower Extremity Functional Scale (LEFS) have been followed.&#x0D;

Qualitative Assessment of Titanium versus Carbon Fiber/Polyetheretherketone Pedicle Screw–Related Artifacts: A Cadaveric Study

Dorsal instrumentation and decompression are the mainstays of spinal tumor treatment. Replacing titanium screws with carbon fiber-reinforced polyetheretherketone (CFRP) screws can reduce imaging artifacts on neural structures and perturbations of radiation dose. Further reduction of metal content in such screws might enhance the benefit. The aim of this study was to assess the artifacts produced by all-titanium screws (Ti-Ti), CFRP thread-titanium screw heads (C-Ti), and all-CFRP screws (C-C). A cadaveric spine was used to place Ti-Ti, C-Ti, and C-C consecutively from T2 to S1. Computed tomography and 1.5T and 3T magnetic resonance imaging were performed for each screw system. Axial T1- and T2-weighted sequences of representative thoracic and lumbar regions were assessed for artifacts. The artifacts were classified as not relevant, considerable, or severe. We evaluated 92 screws and made 178 artifact assessments. The artifacts were clearly visible in computed tomography scans but did not influence the visualization of intraspinal structures. Severe magnetic resonance imaging artifacts were found in 28% (17/60, mostly in the thoracic spine) of Ti-Ti, 2% (1/60, all T1 sequences) of C-Ti, and 0% of C-C, and considerable artifacts were found in 47% (28/60) of Ti-Ti, 10% (6/60, only 1 T2 sequence) of C-Ti, and 0% of C-C screws (P < 0.001). CFRP pedicle screws reduced the artifact intensity in spinal structures compared with titanium screws, and may be beneficial for planning radiotherapy and for follow-up imaging. C-C demonstrated an enhanced effect on dorsal structures.

Implant survival of cemented arthroplasty following failed fixation of proximal femoral fractures in patients aged 30–60 years: a retrospective study with a median follow-up of 10 years

BackgroundGiven the unremitting growth in the volume of failed fixations of proximal femoral fractures (PFFs) in recent years, it is predictable that total hip replacements (THRs) will be the preferred surgical procedure. The long-term survival of cemented THR (CTHR) revisions remains controversial in patients aged 30–60 years. The goal of this retrospective review was to evaluate the 10-year survival of CTHRs following prior failed primary fixations of PFFs in patients aged 30–60 years.MethodsWe retrospectively identified CTHR revisions implemented at four medical centres during 2008–2017 for a failed primary fixation of PFFs in consecutive patients aged 30–60 years. The primary endpoint was implant survival calculated using the Kaplan–Meier method with 95% confidence intervals (CIs); secondary endpoints included functional scores assessed by Harris hip scores (HHS) and main revision-related orthopaedic complications. Follow-up was executed at 1, 2, 3, and 8 years following revision and then at 1-year intervals until the revision, death, or study deadline, whichever occurred first.ResultsIn total, 120 patients (120 hips) who met the eligibility criteria were eligible for follow-up. The median follow-up was 10.2 years (range, 8–12 years). Kaplan–Meier survivorship showed that implant survival with revision for any reason as the endpoint was 95% at 5 years (CI: 93–97%), 89% at 8 years (CI: 86–92%), and 86% at 10 years (CI: 83–89%). Patients treated with three hollow screws had better revision-free survival than patients treated with proximal femoral nail antirotation (PFNA), dynamic hip screw (DHS) or titanium plate plus screws (three p < 0.05). Functional scores were apt to decrease gradually, and at the final follow-up, the mean HHS was 76.9 (range, 67.4–86.4). The overall rate of main revision-related orthopaedic complications was 18.3% (22/120).ConclusionCTHR implemented following prior failed primary fixations of PFFs tends to afford an acceptable 10-year survival, along with advantageous HHS and a low rate of main revision-related orthopaedic complications, which may support an inclination to follow the utilisation of CTHRs, especially in revision settings for intracapsular fractures.

ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION WITH HAMSTRING AUTOGRAFT USING BIOABSORBABLE VERSUS TITANIUM INTERFERENCE SCREW IN TIBIAL TUNNEL IN GOVERNMENT HOSPITAL OF WEST NEPAL

Background: Arthroscopic anterior cruciate ligament reconstruction can be performed both with titanium and bioabsorbable interference screws. The purpose of this study was to com­pare functional outcomes after reconstruction using these different implants. Methods: This was a retrospective study. Patients who underwent ACL reconstruction with ham­string autograft at Bheri hospital over the designed period were observed. Each group (titanium and bioabsorbable screws) consisting of 20 patients were compared using Lyshlom knee scores at 3, 6 and 12 months postoperatively. Statistical analysis was done using SPSS version 24. Chi square test was applied for comparing functional outcomes. Confidence interval of 95%, p value less than 0.05 was taken as significant. Results: Mean Lyshlom scores at 3, 6 and 12 months were 61.70, 69.60 &amp; 85.90 for titanium group and 62.65, 70.95 &amp; 84.65 for bioabsorbable screw group. The differences were not statistically significant. Conclusions: Functional outcomes at each follow up was equivalent among patients using either titanium or bioabsorbable screws.

The Open Book Genioplatsy Technique: A Modification.

Genioplasty is a versatile procedure in the repertoire of a maxillofacial surgeon since the time it was conceptualized by Trauner and Obwegeser in 1957.1 The chin improves the facial profile and renders a definition to the jaw. An aligned and proportionate chin adds ample aesthetic value and youthfulness to the face. In addition, it influences the apparent length of the face. Genioplasty holds the potential to alter the dynamics of facial harmony with minimal effort.2 Failure to perform a much required genioplasty can jeopardize the outcome of hours of an otherwise successful major orthognathic or cosmetic surgery.3 The slope and nature of rotation of the osteotomized segments dictate the extent of vertical and horizontal changes.4 In this article, we attempt to introduce a modification to the existing plethora of genioplasty techniques, particularly aimed to rectify a short square jaw into a feminine one. This technique comprises two conventional oblique osteotomies that split the chin into two components, superior and inferior. A margin of 5 mm is kept superiorly from the root tip, inferiorly from the lower border of mandible, and laterally from the mental foramen. Additional stripping of muscles along the lower border of the mandible ensures adequate mobility of the osteotomized inferior segment. The osteotomized segment is rotated outward and downward at an angle of about 30 to 40 degrees, wherein the tip of the inferior osseous segment is regarded as the prominence of the newfound mentum and the anterior surface of the chin becomes the lower border of the mandible (Fig. 1). The osseous segments are secured using two four-hole, 2.0-mm titanium plates (Fig. 2). Bony margins are smoothed. Hemostasis is achieved. Closure is performed done using 4-0 Vicryl sutures. A 1-year pictorial and radiographic follow-up is charted. The same substantiates the successful outcome of the procedure in terms of desired vertical increment, horizontal augmentation, a feminine round chin with a pointy upheal, and desired labiomental fold.Fig. 1.: Schematic representation of the open book genioplasty technique, in which point A becomes the newfound chin prominence, B becomes the lower border of the mandible, and C is the thickness of the mandible seen upon rotation.Fig. 2.: Osseous segment secured using titanium plates and screws depicting an open book fixation.The design of this open book osteotomy can be deemed ideal for a patient with an existing broad chin who desires a sharper, more feminine one. We have so far performed this procedure on female patients, who require a horizontal advancement of about 10 to 13 mm. The greatest advantage lies in negating a step formation along the lower border of the mandible, contributing to a smooth jawline. The downward rotation of the inferior segment helps acquire additional length, thus leading to a vertical increment in the lower half of the face. The possibility of a dual-plane augmentation makes this technique a versatile one. The thickness of the mentum is a vital consideration, as the osseous volume directly translates to the extent of advancement that can be achieved. In our vast clinical experience, the proposed open book genioplasty technique has had gratifying results with the desired osseous and soft-tissue outcomes in female patients with a short, square chin. ACKNOWLEDGMENT This study conformed to all guidelines of the Declaration of Helsinki. DISCLOSURE The authors have no financial interest to declare in relation to the content of this article. No funding was received for this work.

Arthroscopic Latarjet Procedure Using FiberTape Cerclage With a Simplified Technique for Suture Passage and Coracoid Fixation

Arthroscopic Latarjet has evolved as a reproducible procedure to address significant anterior glenoid bone loss in recurrent anterior instability of the shoulder joint. While arthroscopic Bankart procedure for anterior shoulder instability has changed from metal anchors to absorbable or soft all-suture anchors to avoid metal-ware and subsequent abrasion in cases of osteolysis or backout, Latarjet procedure, until recently couple of titanium screws were used to fix the coracoid bone to the anterior glenoid. Arthroscopic techniques for Latarjet procedure of coracoid bone transfer have shown results similar to the open technique in many recent studies. We use an all-arthroscopic technique that is different and easier from the currently described technique using FiberTape cerclage loops, with 2 ultrabraid tapes fixing the coracoid bone to the prepared anteroinferior glenoid surface. The repair is completed using all-suture anchors to fix the anterior capsule over the attached coracoid, thus exteriorizing the transferred bone and preventing contact with the moving humeral head.

Biodegradation of a Magnesium Alloy Fixation Screw Used in a Guided Bone Regeneration Model in Beagle Dogs.

Nowadays, the most commonly used fixation systems are non-resorbable, but new resorbable magnesium alloy fixation screws have been introduced recently. Therefore, the aim of this study was to compare the magnesium fixation screw and the commonly used non-resorbable titanium screw in an animal model. Four 3-wall defect sites were covered with collagen membranes in the mandible of twenty beagle dogs (two sites on the left and two on the right). Each membrane was fixed with either four magnesium screws or four titanium screws. Post-operative follow-up revealed the expected observations such as transient inflammation and pain. Both groups showed a good healing response, with no differences between groups. Micro-CT analysis showed no significant difference between groups in terms of BV/TV or soft tissue volume. The void volume in the magnesium fixation screw group continued to decrease on average between the different timepoints, but not significantly. Furthermore, a gradual progression of the degradation process of the magnesium screws was observed in the same group. Magnesium screws and titanium screws showed equal performance in tissue regeneration according to GBR principles. An additional advantage of magnesium screws is their resorbable nature, which eliminates the need for a second surgical step to remove the screws.

Evaluation of the cross-section area and flexural strength of fractured rat femurs repaired with titanium and absorbable plates fixation

To compare the mechanical strength of rat femur after complete fracture treated absorbable and titanium plates and screws. Material and methods: A total of 10 male Wistar rats were divided in two groups, according to the femoral fracture fixation: titanium (TG) or absorbable plates (AG). A femur fracture was performed in one side after the corresponding plates of each group were adapted and fixated. The euthanasia occurred with 90 days postoperative, and the fracture femurs were compared with the opposite side control group (CG) in the mechanical tests, through the three-point bending flexural test, and the flexural strength was calculated. Using a digital caliper, the cross-section area was calculated. Data were submitted to the statistical analysis, with the significance level of 0.05. Results: The cross-section in the AG was higher than CG (p &lt; 0.001). With respect of flexural strength, the AG was similar with CG (p = 1.00), and the TG showed lower flexural strength when compared with CG (p = 0.006) and with AG (p = 0.042). Conclusion: The group fixed with absorbable plates demonstrated increased cross-section area compared to the control group and increased flexural strength compared to the group fixed with titanium plates.

Orbital Roof and Lateral Wall Reconstruction Using Split-Thickness Calvarial Bone Graft with Titanium Mesh Complex for a Spheno-Orbital Meningioma

ABSTRACT Objective: To describe our reconstruction of an orbital roof and lateral wall defect using a split- thickness calvarial bone graft with titanium mesh complex after resection of a meningioma of the left greater wing of the sphenoid with extension to the left frontotemporal bone and left orbital roof and lateral wall. Methods: Study Design: Surgical Innovation Setting: Tertiary Private University Hospital Patient: One Results: A 44-year-old woman with a left frontotemporal mass associated with left eye proptosis and epiphora underwent reconstruction of the left orbital roof and lateral wall defect using split-thickness calvarial bone graft with titanium mesh and screws after a left frontotemporal craniectomy, superior and lateral orbital wall resection of a mass of the sphenoid wing with orbital and frontotemporal extension. Final histopathology was consistent with meningioma. Surveillance of the mass and orbital reconstruction showed evidence of bone growth and osteointegration of the titanium mesh into the bone grafts. Conclusion: The initial good outcome of orbital roof and lateral wall reconstruction using split-thickness calvarial bone graft with titanium mesh is evidenced by osteointegration of the titanium mesh and revascularization leading to new bone growth. This autogenous-alloplastic complex may provide a more stable option for orbital reconstruction, but long term follow-up is needed for surveillance of recurrence and monitoring the status of orbital reconstruction.

Occlusion on a Single Implant-Supported Crown: Any differences?

Dental implants react biomechanically to the occlusal forces placed on them, in a different fashion to teeth, which can make them prone to overloading. This can lead to a range of mechanical problems, including screw loosening, ceramic chipping, and fracture of components, but it can also be associated with biological complications such as later peri-implantitis. Appropriate occlusal loading is essential to maintain long-term stability of implant-retained restorations. Clinicians must be aware that, to varying extents, complications do occur with single implant-retained crowns. Dental implants are not a panacea; it is unwise to describe implants as being either perfect or permanent because they are neither. Patients need to understand, well in advance of having implant-based treatment, that the placement of titanium in their jaw(s) will not stop their parafunctional habits, such as clenching or bruxism. Insertion of titanium screws of various types and roughness will certainly not alter their susceptibility to their own plaque-induced inflammatory periodontal disease which is often manifested as peri-mucositis, or later as peri-implantitis in susceptible patients. Based on the available data, this paper provides recommendations to optimise clinical outcomes for single implant-supported crowns. When designing implants, the focus should be on achieving axial forces during chewing. It is wise to minimise horizontal and non-axial loads to avoid potential damage to ceramic or other prosthetic components, and to minimise the risks of bone resorption occurring around the implants themselves at a later stage. Occlusal relationships of implant-retained restorations should be carefully evaluated on a regular basis. Accurate occlusal records of the starting point are extremely helpful in assessing the ongoing status of any restorations.