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The purpose of this research was to evaluate the structural stress and deformation of a newly designed onplant miniplate anchorage system compared to a standard anchorage system. A bone block integrated with a novel miniplate and fixation screw system was simulated in a three-dimensional model and subjected to force at different directions. The stress distribution and deformation of the miniplate system and cortical bone were evaluated using the three-dimensional finite element method. The results showed that the stress on the plate system and bone was linearly proportional to the force magnitude and was higher when the force was in a vertical direction (Y-axis). Stress and deformation values of the two screws (screw 1 and 2) were asymmetric when the force was added along Y-axis and was greater in screw 1. The highest deformation value of the screws was 7.5148 μm, much smaller than the limit value. The load was decreased for each single miniscrew, and the ability of the new anchorage system to bear the load was also enhanced to some degree. It was suggested that the newly designed onplant miniplate anchorage system is effective, easily implanted and minimally invasive.

Background: Bone drilling is widely used in orthopaedics for fracture treatment, reconstructive surgery and bone biopsy. Heat generation in bone drilling can cause rise in bone temperature resulting in prolonged healing time or loosening of fixation., Objective: The purpose of this study was to investigate thermal anisotropy of bone by measuring the level of temperature in bone drilling with and without cooling conditions in two anatomical directions., Methods: Drilling tests were performed on bovine cortical bone. A total of fifteen specimens were used to obtain data for statistical analysis. Temperature near the cutting zone was measured in two anatomical directions. i.e. along the longitudinal and circumferential direction. Temperature distribution was also found in the two prescribed directions. Analysis of variance (ANOVA) was used to identify significant drilling parameter affecting bone temperature., Results: Drilling speed, feed rate and drill size were found influential parameters affecting bone temperature. Higher drilling speed, feed rate, and large drill size were found to cause elevated temperature in bone. Much lower temperature was measured in bone when cooling fluid was supplied to the drilling region. Experimental results revealed lower temperatures in the circumferential direction compared to the longitudinal direction., Conclusions: Thermal anisotropy for heat transport was found in the bone. This study recommends lower drilling speed and feed rate and cooling for controlling rise in bone temperature.

Hypothesis: Glenoid retroversion can be corrected with standard glenoid implants after anterior-side asymmetric reaming or by using posterior augmented glenoid implants with built-in corrections. The purpose of this study was to compare 2 augmented glenoid designs with a standard glenoid design, measure the amount of bone removed, and compute the stresses generated in the cement and bone., Methods: Finite element models of 3 arthritic scapulae with varying severities of posterior glenoid wear were each implanted with 4 different implant configurations: standard glenoid implant in neutral alignment with asymmetric reaming, standard glenoid implant in retroversion, glenoid implant augmented with a posterior wedge in neutral alignment, and glenoid implant augmented with a posterior step in neutral alignment. The volume of cortical and cancellous bone removed and the percentage of implant back surface supported by cortical bone were measured. Stresses and strains in the implant, cement, and glenoid bone were computed., Results: Asymmetric reaming for the standard implant in neutral version required the most bone removal, resulted in the lowest percentage of back surface supported by cortical bone, and generated strain levels that risked damage to the most bone volume. The wedged implant removed less bone, had a significantly greater percentage of the back surface supported by cortical bone, and generated strain levels that risked damage to significantly less bone volume., Conclusions: The wedged glenoid implants appear to have various advantages over the standard implant for the correction of retroversion., Level of Evidence: Basic Science Study; Computer Modeling., (Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.)

Background: The effect of femoral tunnel widening on clinical outcomes of anterior cruciate ligament (ACL) reconstruction has been rarely investigated. In this study, ACL reconstructions were performed using semitendinosus and gracilis (STG) tendon grafts and single cortical fixation on the femoral side. The aim was to analyze femoral tunnel widening at one year and to evaluate its effect on clinical and laximetric outcomes., Methods: A total of 46 patients were enrolled in this prospective continuous single-operator monocenter study. Clinical protocol included pre-operative and one-year evaluation with subjective and objective International Knee Documentation Committee (IKDC) clinical scores. Computed tomography (CT) scan was used for radiographic examination during the follow-up period. The femoral tunnel widening was measured as a three-dimensional (3D) image using OsiriX software. The cross-sectional area of each tunnel was measured at four different locations., Results: The subjective preoperative IKDC score was 50 and one-year postoperative score was 81.8. The side-to-side difference in knee laxity decreased from 2.94 to 0.74 mm. The objective IKDC score during the final follow-up was rated A in 27 patients and B in 17. CT scan data revealed an average of 49.32% cone-shaped widening of the femoral tunnel. Femoral tunnel widening at the level of the joint (F4) was negatively correlated with the IKDC subjective score at one year., Conclusions: This study revealed a significant widening of the femoral tunnel by demonstrating its conical shape at one year post-surgery. A significant correlation could be established between femoral tunnel widening close to the joint and IKDC scores., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Background: We evaluated the incidence of medial cortical fracture and influence on the loss of the correction angle in computer-assisted closing-wedge high tibial osteotomy., Methods: Using a navigation system, 200 closing-wedge high tibial osteotomies were performed. The correction angle was defined as the difference between the pre- and postoperative medial proximal tibial angles. The change in the medial proximal tibial angle was calculated as the difference between the medial proximal tibial angles two weeks and one year postoperatively. The medial cortical fractures of the osteotomy site were evaluated. Their incidence, risk factors, and influence on the loss of correction angle were analyzed., Results: The incidence of non-displaced cortical breakage and displaced cortical fracture was 28.0% and 6.5%, respectively. Medial cortical fracture was more frequent in younger patients and patients with severe preoperative varus deformity. The average correction angle was significantly larger in the displaced cortical fracture group (9.6° vs. 12.7°, p<0.001). The average change in the medial proximal tibial angle in the no fracture, non-displaced cortical breakage, and displaced cortical fracture groups was 0.7°, 1.8°, and 4.4°, respectively (p<0.001)., Conclusions: Medial cortical fracture could not be prevented in all knees, even using the navigation system. The risk of medial cortical fracture and loss of the correction angle was increased, particularly when a greater correction angle is required in young patients., Level of Evidence: IV., (Copyright © 2015. Published by Elsevier B.V.)

Study Design: Cadaveric biomechanical study., Objective: To determine fatigue behavior of cortical bone trajectory (CBT) pedicle screws., Summary of Background Data: Cortical bone trajectory screws have been becoming popular in spine surgery; however, the long-term fatigue behavior of the new CBT screws remains understudied and limitations not well defined., Methods: Twelve vertebrae from six cadaveric lumbar spines were obtained. After bone mineral density (BMD) measurements, each vertebral body was instrumented with screws from each group, that is, CBT (4.5 × 25 mm) or standard pedicle screw (6.5 × 55 mm). A load (± 4 Nm sagittal bending) was applied under displacement control at 1 Hz. Each construct was loaded for 100 cycles or until 6° of loosening was observed. After fatigue testing, the screws were pulled out axially at 5 mm/min., Results: The standard pedicle screw showed better resistance against 100 cycle loading compared with the CBT screws (P < 0.001, 6.9° ± 4.8° vs. 15.2° ± 5.5°, respectively). The standard pedicle screw testing usually required more than 100 cycles of loading to achieve the critical loosening (3592 ± 4564 cycles), whereas the CBT screw never exceeded 100 cycles (84 ± 24 cycles) (P = 0.002). Increased BMD was significantly associated with a higher number of cycles and less loosening. The standard pedicle screw group had a higher postfatigue pullout load than the CBT screw group (P = 0.001, 776 ± 370 N and 302 ± 232 N, respectively)., Conclusion: The standard pedicle screw had a better fatigue performance compared with the CBT screw in vertebra with compromised bone quality. The proper insertion of the CBT screw might be prevented by the laminar anatomy depending on the screw head design. The CBT screw damaged the bone along its shaft by rotating around a fulcrum, located at either the pars, pedicle isthmus, or the junction of the pedicle and superior endplate, contingent upon the strength of the bone.

Background: Studies have shown that bone quality at the implant recipient site can influence primary stability., Purpose: The aims of this study were to explore the quantitative estimation of the primary stability of implants preoperatively using CT values and to examine the effect of different implant designs with recommended socket preparation on primary stability., Materials and Methods: Forty-four fresh porcine femoral heads were prepared. The bone surrounding implant sockets was preoperatively evaluated by helical CT. Forty-four implants (φ 4.3 × 10 mm), 22 straight and 22 tapered, were placed according to the manufacturer's instructions. The insertion torque value (ITV), implant stability quotient (ISQ), and removal torque value (RTV) were recorded as indicators of primary implant stability., Results: Significant correlations and linear relationships were found between the CT value and ITV, ISQ, and RTV for both straight and tapered implants (Spearman's correlation coefficient, p < .001; linear regression analysis, p < .01). Tapered implants had a significantly higher ITV than straight implants (analysis of covariance, p < .01)., Conclusions: Obtained results suggest that the primary stability of implants could be quantitatively estimated using the CT value preoperatively, indicating the CT value of bone surrounding an implant can contribute considerably to implant planning and design choice in clinical situations., (© 2014 Wiley Periodicals, Inc.)

Purpose: Various parameters can influence temperature rise and detection during implant site preparation. The aim of this study is to investigate local temperature values in cortical and corticocancellous bovine bone during early stages of piezoelectric implant site preparation., Materials and Methods: 20 osteotomies were performed using a diamond tip (IM1s, Mectron Medical Technology, Carasco, Italy) on two different types of bovine bone samples, cortical and corticocancellous, respectively. A standardized protocol was designed to provide constant working conditions. Temperatures were measured in real time at a fixed position by a fiber optic thermometer., Results: Significantly higher drilling time (154.90 sec versus 99.00 sec; p < 0.0001) and temperatures (39.26°C versus 34.73°C; p = 0.043) were observed in the cortical group compared to the corticocancellous group. A remarkable variability of results characterized the corticocancellous blocks as compared to the blocks of pure cortical bone., Conclusion: Bone samples can influence heat generation during in vitro implant site preparation. When compared to cortical bone, corticocancellous samples present more variability in temperature values. Even controlling most experimental factors, the impact of bone samples still remains one of the main causes of temperature variability.

The stability of segments after Le Fort I osteotomy first attracted the researcher's interest when the surgical concept was conceived. Prebent plates are the ultimate modification of plate systems in craniofacial surgery; they have two right angles and are available in different lengths for use in maxillary advancement surgery. For this research, cone-beam computed tomography (CBCT) images of a male patient were obtained and scanned, and a 3D maxillary bone was created. Conventional Le Fort I osteotomies with 5 and 10 mm advancements were performed on both the cortical and trabecular bone using the Surgical Simulation Module of Mimics software; 1.7 mm Leibinger standard orthognathic 5-hole L plates and 1.7 mm Leibinger orthognathic advancement 11-hole prebent plates were adapted to the fragments. Displacement of the segment, the von Mises (VM) stresses (on the titanium miniplates) and the maximum principal (MP) stresses (on the bone) were evaluated for each configuration. Prebent plates offer a good alternative to the conventional two plate system, except in operations where maxillary advancement exceeds 5 mm. Surgical procedures that include advancement exceeding 5 mm or vertical position changes remain controversial and further studies are needed., (Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

There are many orbital wall reconstruction materials that can be used in surgery for orbital blowout fractures. We consider autogenous bone grafts to have the best overall characteristics among these materials and use thinned, inner cortical tables of the ilium. A bone bender is normally used to shape the inner iliac table to match the orbital shape. Since orbital walls curve three-dimensionally, processing of bone grafts is not easy and often requires much time and effort. We applied a triangular approximation method to the processing of bone grafts. Triangular approximation is a concept used in computer graphics for polygon processing. In this method, the shape of an object is represented as combinations of polygons, mainly triangles. In this study, the inner iliac table was used as a bone graft, and cuts or scores were made to create triangular sections. These triangular sections were designed three-dimensionally so that the shape of the resulting graft approximated to the three-dimensional orbital shape. This method was used in 12 patients with orbital blowout fractures, which included orbital floor fractures, medial wall fractures, and combined inferior and medial wall fractures. In all patients, bone grafts conformed to the orbital shape and good results were obtained. This simple method uses a reasonable and easy-to-understand approach and is useful in the treatment of bone defects in orbital blowout fractures when using a hard graft material., (Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Background: The aim of the present study is to compare the keratinized gingival tissue (KT) height labial to the mandibular incisors after active orthodontic treatment (AOT) with and without alveolar corticotomy and bone grafting., Methods: Two orthodontically treated groups of 35 patients each, with (Cort) and without (Conv) alveolar decortication and augmentation bone grafting, are matched in this case-control study for sample size, sex, mandibular premolar extractions, pretreatment age, post-treatment observation period, and pretreatment KT height. Standardized digital frontal occlusion photographs taken before and at least 1 year after AOT were adjusted to 96 dots per inch and measured with image analysis software for vertical KT height labial to each mandibular incisor., Results: An average of 1.5 years after completion of AOT, KT height had increased significantly by 0.78 mm (P < 0.001) in the Cort group and decreased 0.38 mm (P = 0.002) in the Conv group; a 1.28-mm KT height gain was demonstrated in the subgroup representing the lowest half of Cort KT height at pretreatment. Mandibular incisor inclination and prominence explained neither the decrease in KT height in Conv nor the KT height gain in Cort., Conclusions: Orthodontic therapy combined with alveolar decortication and augmentation bone grafting resulted in a significant increase in KT height. Although KT height surrounding the dentition has been devalued by evidence-based studies, the value-added protection of KT height increase after decortication and augmentation bone grafting offsets the concerns of orthodontic proclination or expanding mandibular incisors facially.

Objectives: To assess heat generation in osteotomies during application of sonic and ultrasonic saws compared to conventional bur., Methods: Two glass-fiber isolated nickel-chromium thermocouples, connected to a recording device, were inserted into fresh bovine rib bone blocks and kept in 20 ± 0.5 °C water at determined depths of 1.5 mm (cortical layer) and 7 mm (cancellous layer) and 1.0 mm away from the planned osteotomy site. Handpieces, angulated 24-32°, were mounted in a vertical drill stand, and standardized weights were attached to their tops to exert loads of 5, 8, 15 and 20 N. Irrigation volumes of 20, 50 and 80 ml/min were used for each load. Ten repetitions were conducted using new tips each time for each test condition. The Mann-Whitney-U test was used for statistical analysis (p < 0.05)., Results: Both ultrasonic and sonic osteotomies were associated with significantly lower heat generation than conventional osteotomy (p < 0.01). Sonic osteotomy showed non-significantly lower heat generation than ultrasonic osteotomy. Generated heat never exceeded the critical limit of 47 °C in any system. Variation of load had no effect on heat generation in both bone layers for all tested systems. An increased irrigation volume resulted in lower temperatures in both cortical and cancellous bone layers during all tested osteotomies., Conclusion: Although none of the systems under the conditions of the present study resulted in critical heat generation, the application of ultrasonic and sonic osteotomy systems was associated with lower heat generation compared to the conventional saw osteotomy. Copious irrigation seems to play a critical role in preventing heat generation in the osteotomy site., (Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Objective: To evaluate if the improved accelerated osteogenic orthodontics (IAOO) procedure could speed Class III surgical patients' preoperative orthodontic treatment duration and, if yes, to what extent. This study was also designed to determine whether or not an IAOO procedure affects the tooth-moving pattern during extraction space closure., Materials and Methods: The samples in this study consisted of 24 Class III surgical patients. Twelve skeletal Class III surgery patients served as an experimental group (group 1) and the others as a control group (group 2). Before treatment, the maxillary first premolars were removed. For group 1, after the maxillary dental arch was aligned and leveled (T2), IAOO procedures were performed in the maxillary alveolar bone. Except for this IAOO procedure in group 1, all 24 patients experienced similar combined orthodontic and orthognathic treatment. Study casts of the maxillary dentitions were made before orthodontic treatment (T1) and after extraction space closure (T3). All of the casts were laser scanned, and the amount of movement of the maxillary central incisor, canine, and first molar, as well as arch widths, were digitally measured and analyzed by using the three-dimensional model superimposition method., Results: The time durations T3-T2 were significantly reduced in group 1 by 8.65 ± 2.67 months and for T3-T1 were reduced by 6.39 ± 2.00 months (P < .001). Meanwhile, the tooth movement rates were all higher in group 1 (P < .05). There were no significant differences in the amount of teeth movement in the sagittal, vertical, and transverse dimensions between the two groups (P > .05)., Conclusion: The IAOO can reduce the surgical orthodontic treatment time for the skeletal Class III surgical patient by more than half a year on average. The IAOO procedures do not save anchorage.

Several surgical techniques based on corticotomy and dental distraction have been developed to improve the movement of teeth and reduce the duration of orthodontic treatment. In this systematic review we have critically assessed published studies on the experimental movement of teeth to find out whether operations such as corticotomy and dental distraction osteogenesis increase the rate of movement, and to find out which biological mechanisms are engaged during surgically facilitated orthodontics, and which complications may be seen. We searched PubMed and Embase for publications until January 2014 and screened the titles and abstracts. Articles that met the inclusion criteria were retrieved in full and assessed independently by 2 of the authors. A total of 22 studies were included, and corticotomy and distraction techniques were the main surgical methods. Generally, all studies reported that movement of teeth was faster after operation than with conventional orthodontics. The peak velocity was always at an early postoperative stage regardless of the surgical technique used. Immunohistological data showed simultaneous regional increases in catabolic and anabolic activity. Histomorphometric data showed more direct resorption of bone and less hyalinisation after operation, and a reduced bone volume density around the surgical site. When present, complications such as root resorption or periodontal problems were minimal. Current experimental animal studies show that procedures such as corticotomy and dental distraction can accelerate the movement of teeth without severe complications because of the regional increase in catabolic and anabolic remodelling., (Copyright © 2015 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Objective: The purpose of this study was to demonstrate the lumbar pedicle cortical bone trajectory (CBT) screw fixation technique, a new fixation technique for lumbar surgery., Data Sources: The data analyzed in this review are mainly from articles reported in PubMed published from 1994 to 2014., Study Selection: Original articles and critical reviews relevant to CBT technique and lumbar pedicle fixation were selected., Results: CBT technique was firstly introduced as a new fixation method for lumbar pedicle surgery in 2009. The concepts, morphometric study, biomechanical characteristics and clinical applications of CBT technique were reviewed. The insertional point of CBT screw is located at the lateral point of the pars interarticularis, and its trajectory follows a caudocephalad path sagittally and a laterally directed path in the transverse plane. CBT technique can be used for posterior fixation during lumbar fusion procedures. This technique is a minimally invasive surgery, which affords better biomechanical stability, fixation strength and surgical safety. Therefore, CBT technique has the greatest benefit in lumbar pedicle surgery for patients with osteoporosis and obesity., Conclusion: CBT technique is a better alternative option of lumbar pedicle fixation, especially for patients with osteoporosis and obesity.