The Experts below are selected from a list of 1932 Experts worldwide ranked by ideXlab platform

Yi Zhang - One of the best experts on this subject based on the ideXlab platform.

  • Condylar Fracture and temporomandibular joint ankylosis
    Chinese journal of stomatology, 2016
    Co-Authors: Yi Zhang
    Abstract:

    This article summarized the advances in treatment and research of temporomandibular joint surgery in the last 5 years which was presented in "The 2nd Condyle Fracture and Temporomandibular Joint Ankylosis Symposium". The content includes 5 parts: non-surgical treatment of children condyle Fracture and long-term follow-up, the improvement of operative approach for condyle Fracture and key techniques, the importance and the method for the simultanesous reduction of disc in Condylar Fracture treatment, the development of traumatic temporomandibular joint ankylosis similar to hypertrophic non-union and the improved safety and accuracy by applying digital surgery in joint surgery.

  • a retrospective study of using removable occlusal splint in the treatment of Condylar Fracture in children
    Journal of Cranio-maxillofacial Surgery, 2014
    Co-Authors: Yuming Zhao, Jie Yang, Lihong Ge, Yi Zhang
    Abstract:

    Abstract Background Although the concept of conservative treatment for paediatric Condylar Fracture is well understood, there is still a lack of a recognized method for treating child patients with a Condylar Fracture. The purpose of this study was to investigate the effect of the removable occlusal splint in treating Condylar Fractures in children and adolescents. Materials and methods Forty children and adolescents with Condylar Fracture, aged 3–16, were included in this study. A removable occlusal splint with varying thickness was fabricated according to the age, developmental stage of the mandible, and degree of Condylar dislocation. This was worn for 1–3 months, accompanied by functional exercises. Follow-up was carried out by clinical observation and panoramic X-ray. Results Clinically satisfactory results with good occlusion were obtained in all the patients, along with unimpaired function and normal growth and development of the mandible. The panoramic image showed remodelling and reconstruction of the Fractured condyles. Conclusions Our results confirm that conservative treatment has a satisfactory clinical outcome in treating Condylar Fracture in children. The removable occlusal splint is a promising approach for treating Condylar Fracture in children and adolescents.

  • a pilot trial on the molecular pathophysiology of traumatic temporomandibular joint bony ankylosis in a sheep model part ii the differential gene expression among fibrous ankylosis bony ankylosis and Condylar Fracture
    Journal of Cranio-maxillofacial Surgery, 2014
    Co-Authors: Yingbin Yan, E Xiao, Y H Gan, Yi Zhang
    Abstract:

    Abstract Objective The purpose of the study was to preliminarily explore the differential expressions of a series of genes regulating bone formation in temporomandibular joint (TMJ) fibrous ankylosis, bony ankylosis and Condylar Fracture healing. Methods The cDNA from either the bony ankylosed callus or Fracture callus of the 6 sheep, as described in the part I, were both used in the study. The differences of gene expressions between bony ankylosis and Condylar Fracture at 1, 3, and 6 months postoperatively were measured by real-time PCR, with 2 samples at each time point. In addition, another 2 sheep were added to have fibrous ankylosis induced on the right TMJ, and 1 sheep was sacrificed at 3 and 6 months after surgery, respectively. The differences of gene expressions between fibrous and bony ankylosis at 3 and 6 months postoperatively were measured by real-time PCR. Results Bony ankylosis showed higher mRNA expression trends in Wnt2b, Wnt5a, β-Catenin, Lef1, CyclinD1, Runx2, Osterix, Sox9, Col10a1, Alp, Ocn, Bmp2, and Bmp7 compared to fibrous ankylosis, although no statistical analysis was performed due to the very small sample size. Whereas bony ankylosis showed a significant lower expression of Wnt5a, β-Catenin, Lef1, Runx2, Osterix, Sox9, Col10a1, Alp, Ocn and Bmp4 compared to Condylar Fracture at several time points ( P Conclusion Our data provided a preliminary molecular evidence for the hypothesis that the development of traumatic TMJ bony ankylosis was the course of delayed bone healing or hypertrophic nonunion, and deserved to be further studied.

  • a pilot trial on the molecular pathophysiology of traumatic temporomandibular joint bony ankylosis in a sheep model part i expression of wnt signaling
    Journal of Cranio-maxillofacial Surgery, 2014
    Co-Authors: Yingbin Yan, E Xiao, Y H Gan, Yi Zhang
    Abstract:

    Abstract Objective To preliminarily investigate the temporal patterns of the endogenous mRNA expression for members of the Wnt signaling and a series of genes regulating bone formation during the development of traumatic temporomandibular joint (TMJ) bony ankylosis in a sheep model. Methods Six sheep were used for the induction of bony ankylosis of TMJ. We performed a Condylar Fracture, excision of the lateral 2/3 disc and serious injury to the glenoid fossa to induce bony ankylosis on the right TMJ. An isolated Condylar Fracture was performed on the left side. Two sheep were sacrificed at 1 month, 3 months, and 6 months after surgery, respectively. The specimens from the ankylosed joint and the Condylar Fracture were harvested for RNA extraction respectively. In this report (Part I), only the bony ankylosed samples were used for analysis of gene expressions. The specimens 1 month postoperatively were taken as the control, and the changes of expression of target genes over time were examined by real-time PCR. Results mRNA expression of Wnt1, Wnt2b, Wnt3a, β-catenin, Sfrp1, Lrp6, Lef1, CyclinD1, and Runx2 was up-regulated at 3 and 6 months compared with 1 month. The expression of Wnt5a, Sox9, and Osterix was up-regulated with a peak at 3 months, and then fell back to the basal levels at 6 months. The expression of Ocn began to up-regulate until 6 month postoperatively. Conclusion Our findings suggested that Wnt signaling was involved in the formation of traumatic TMJ bony ankylosis and thus may be a potential therapeutic target for the treatment of the disease in the future.

  • surgical induction of tmj bony ankylosis in growing sheep and the role of injury severity of the glenoid fossa on the development of bony ankylosis
    Journal of Cranio-maxillofacial Surgery, 2013
    Co-Authors: Yingbin Yan, Yi Zhang, Y H Gan, E Xiao
    Abstract:

    Abstract Objective The purpose of this paper is to summarize our experiences in creating an animal model of TMJ bony ankylosis based on 2 sequential experiments. Methods Two sequential experiments were performed with the aim of creating a model of TMJ bony ankylosis. Seven growing sheep were used in the first experiment, in which 1 was served as a control animal. Condylar Fracture with disc preservation was performed on the control side. On the contralateral side, Condylar Fracture, excision of the lateral 2/3 disc and injury to the glenoid fossa were performed to induce bony ankylosis. Three animals were sacrificed respectively at 3 and 6 months after surgery. In the second experiment, 7 growing sheep were used. The only difference of modeling between the 2 experiments was that more serious injury to the glenoid fossa was made in the ankylosis-induced side in experiment 2. Three, 2, and 2 animals were sacrificed respectively at 1, 3, and 6 months postoperatively. The TMJ complexes were examined by computed tomography (CT) and histological evaluation. Results In experiment 1, only fibrous ankylosis was observed in the ankylosis-induced side both at 3 and 6 months postoperatively. In experiment 2, CT and histological evaluation showed that the outcomes of the ankylosis-induced side were fibrous-bony ankylosis, fibrous-bony ankylosis, and bony ankylosis respectively at 1, 3, and 6 months after surgery. Conclusion Through summarizing the differences of the modeling and the different outcomes in the 2 experiments, we concluded that severe damage to the glenoid fossa played an important role in the development of TMJ bony ankylosis.

Yingbin Yan - One of the best experts on this subject based on the ideXlab platform.

  • preserving the fibrous layer of the mandibular condyle reduces the risk of ankylosis in a sheep model of intracapsular Condylar Fracture
    Journal of Oral and Maxillofacial Surgery, 2018
    Co-Authors: Hualun Wang, Peipei Zhang, Li Meng, Suxia Liang, Hao Liu, Yingbin Yan
    Abstract:

    Purpose The aim of this experimental study was to investigate the role of the fibrous layer of the Condylar head in the formation of temporomandibular joint (TMJ) ankylosis in a sheep model of intracapsular Condylar Fracture. Materials and Methods Six growing Xiao-wei Han sheep were used in the study, and bilateral TMJ surgery was performed in each sheep. In the left TMJ, sagittal Fracture of the condyle, removal of the fibrous layer of the Condylar head, excision of two thirds of the disc, and removal of the fibrous zone of the glenoid fossa were performed. In the right TMJ, the same surgical management was performed, except that in each sheep, the fibrous layer of the Condylar head was preserved. Three sheep were killed humanely at 1 month postoperatively, and the other 3 sheep were killed humanely at 3 months postoperatively. The TMJ complexes were examined by histologic evaluation. Results Fibrous ankylosis was observed on the left side in 3 sheep at 1 month postoperatively and in 2 of 3 sheep at 3 months postoperatively. Fibro-osseous ankylosis was achieved on the left side in 1 sheep at 3 months postoperatively. In the right TMJ, the main postoperative histologic findings included Condylar Fracture healing, topical rupture or exfoliation of the fibrous layer of the condyle, and fissure between the fibrous layer and the proliferative zone of the condyle. However, no evidence of ankylosis was observed. The TMJ ankylosis scores on the right side were significantly lower than those on the left side at different time points (P  Conclusions This study showed that the presence of the fibrous layer of the Condylar head prevented the development of TMJ ankylosis in a sheep model of intracapsular Condylar Fracture.

  • a pilot trial on the molecular pathophysiology of traumatic temporomandibular joint bony ankylosis in a sheep model part ii the differential gene expression among fibrous ankylosis bony ankylosis and Condylar Fracture
    Journal of Cranio-maxillofacial Surgery, 2014
    Co-Authors: Yingbin Yan, E Xiao, Y H Gan, Yi Zhang
    Abstract:

    Abstract Objective The purpose of the study was to preliminarily explore the differential expressions of a series of genes regulating bone formation in temporomandibular joint (TMJ) fibrous ankylosis, bony ankylosis and Condylar Fracture healing. Methods The cDNA from either the bony ankylosed callus or Fracture callus of the 6 sheep, as described in the part I, were both used in the study. The differences of gene expressions between bony ankylosis and Condylar Fracture at 1, 3, and 6 months postoperatively were measured by real-time PCR, with 2 samples at each time point. In addition, another 2 sheep were added to have fibrous ankylosis induced on the right TMJ, and 1 sheep was sacrificed at 3 and 6 months after surgery, respectively. The differences of gene expressions between fibrous and bony ankylosis at 3 and 6 months postoperatively were measured by real-time PCR. Results Bony ankylosis showed higher mRNA expression trends in Wnt2b, Wnt5a, β-Catenin, Lef1, CyclinD1, Runx2, Osterix, Sox9, Col10a1, Alp, Ocn, Bmp2, and Bmp7 compared to fibrous ankylosis, although no statistical analysis was performed due to the very small sample size. Whereas bony ankylosis showed a significant lower expression of Wnt5a, β-Catenin, Lef1, Runx2, Osterix, Sox9, Col10a1, Alp, Ocn and Bmp4 compared to Condylar Fracture at several time points ( P Conclusion Our data provided a preliminary molecular evidence for the hypothesis that the development of traumatic TMJ bony ankylosis was the course of delayed bone healing or hypertrophic nonunion, and deserved to be further studied.

  • a pilot trial on the molecular pathophysiology of traumatic temporomandibular joint bony ankylosis in a sheep model part i expression of wnt signaling
    Journal of Cranio-maxillofacial Surgery, 2014
    Co-Authors: Yingbin Yan, E Xiao, Y H Gan, Yi Zhang
    Abstract:

    Abstract Objective To preliminarily investigate the temporal patterns of the endogenous mRNA expression for members of the Wnt signaling and a series of genes regulating bone formation during the development of traumatic temporomandibular joint (TMJ) bony ankylosis in a sheep model. Methods Six sheep were used for the induction of bony ankylosis of TMJ. We performed a Condylar Fracture, excision of the lateral 2/3 disc and serious injury to the glenoid fossa to induce bony ankylosis on the right TMJ. An isolated Condylar Fracture was performed on the left side. Two sheep were sacrificed at 1 month, 3 months, and 6 months after surgery, respectively. The specimens from the ankylosed joint and the Condylar Fracture were harvested for RNA extraction respectively. In this report (Part I), only the bony ankylosed samples were used for analysis of gene expressions. The specimens 1 month postoperatively were taken as the control, and the changes of expression of target genes over time were examined by real-time PCR. Results mRNA expression of Wnt1, Wnt2b, Wnt3a, β-catenin, Sfrp1, Lrp6, Lef1, CyclinD1, and Runx2 was up-regulated at 3 and 6 months compared with 1 month. The expression of Wnt5a, Sox9, and Osterix was up-regulated with a peak at 3 months, and then fell back to the basal levels at 6 months. The expression of Ocn began to up-regulate until 6 month postoperatively. Conclusion Our findings suggested that Wnt signaling was involved in the formation of traumatic TMJ bony ankylosis and thus may be a potential therapeutic target for the treatment of the disease in the future.

  • surgical induction of tmj bony ankylosis in growing sheep and the role of injury severity of the glenoid fossa on the development of bony ankylosis
    Journal of Cranio-maxillofacial Surgery, 2013
    Co-Authors: Yingbin Yan, Yi Zhang, Y H Gan, E Xiao
    Abstract:

    Abstract Objective The purpose of this paper is to summarize our experiences in creating an animal model of TMJ bony ankylosis based on 2 sequential experiments. Methods Two sequential experiments were performed with the aim of creating a model of TMJ bony ankylosis. Seven growing sheep were used in the first experiment, in which 1 was served as a control animal. Condylar Fracture with disc preservation was performed on the control side. On the contralateral side, Condylar Fracture, excision of the lateral 2/3 disc and injury to the glenoid fossa were performed to induce bony ankylosis. Three animals were sacrificed respectively at 3 and 6 months after surgery. In the second experiment, 7 growing sheep were used. The only difference of modeling between the 2 experiments was that more serious injury to the glenoid fossa was made in the ankylosis-induced side in experiment 2. Three, 2, and 2 animals were sacrificed respectively at 1, 3, and 6 months postoperatively. The TMJ complexes were examined by computed tomography (CT) and histological evaluation. Results In experiment 1, only fibrous ankylosis was observed in the ankylosis-induced side both at 3 and 6 months postoperatively. In experiment 2, CT and histological evaluation showed that the outcomes of the ankylosis-induced side were fibrous-bony ankylosis, fibrous-bony ankylosis, and bony ankylosis respectively at 1, 3, and 6 months after surgery. Conclusion Through summarizing the differences of the modeling and the different outcomes in the 2 experiments, we concluded that severe damage to the glenoid fossa played an important role in the development of TMJ bony ankylosis.

E Xiao - One of the best experts on this subject based on the ideXlab platform.

  • a pilot trial on the molecular pathophysiology of traumatic temporomandibular joint bony ankylosis in a sheep model part ii the differential gene expression among fibrous ankylosis bony ankylosis and Condylar Fracture
    Journal of Cranio-maxillofacial Surgery, 2014
    Co-Authors: Yingbin Yan, E Xiao, Y H Gan, Yi Zhang
    Abstract:

    Abstract Objective The purpose of the study was to preliminarily explore the differential expressions of a series of genes regulating bone formation in temporomandibular joint (TMJ) fibrous ankylosis, bony ankylosis and Condylar Fracture healing. Methods The cDNA from either the bony ankylosed callus or Fracture callus of the 6 sheep, as described in the part I, were both used in the study. The differences of gene expressions between bony ankylosis and Condylar Fracture at 1, 3, and 6 months postoperatively were measured by real-time PCR, with 2 samples at each time point. In addition, another 2 sheep were added to have fibrous ankylosis induced on the right TMJ, and 1 sheep was sacrificed at 3 and 6 months after surgery, respectively. The differences of gene expressions between fibrous and bony ankylosis at 3 and 6 months postoperatively were measured by real-time PCR. Results Bony ankylosis showed higher mRNA expression trends in Wnt2b, Wnt5a, β-Catenin, Lef1, CyclinD1, Runx2, Osterix, Sox9, Col10a1, Alp, Ocn, Bmp2, and Bmp7 compared to fibrous ankylosis, although no statistical analysis was performed due to the very small sample size. Whereas bony ankylosis showed a significant lower expression of Wnt5a, β-Catenin, Lef1, Runx2, Osterix, Sox9, Col10a1, Alp, Ocn and Bmp4 compared to Condylar Fracture at several time points ( P Conclusion Our data provided a preliminary molecular evidence for the hypothesis that the development of traumatic TMJ bony ankylosis was the course of delayed bone healing or hypertrophic nonunion, and deserved to be further studied.

  • a pilot trial on the molecular pathophysiology of traumatic temporomandibular joint bony ankylosis in a sheep model part i expression of wnt signaling
    Journal of Cranio-maxillofacial Surgery, 2014
    Co-Authors: Yingbin Yan, E Xiao, Y H Gan, Yi Zhang
    Abstract:

    Abstract Objective To preliminarily investigate the temporal patterns of the endogenous mRNA expression for members of the Wnt signaling and a series of genes regulating bone formation during the development of traumatic temporomandibular joint (TMJ) bony ankylosis in a sheep model. Methods Six sheep were used for the induction of bony ankylosis of TMJ. We performed a Condylar Fracture, excision of the lateral 2/3 disc and serious injury to the glenoid fossa to induce bony ankylosis on the right TMJ. An isolated Condylar Fracture was performed on the left side. Two sheep were sacrificed at 1 month, 3 months, and 6 months after surgery, respectively. The specimens from the ankylosed joint and the Condylar Fracture were harvested for RNA extraction respectively. In this report (Part I), only the bony ankylosed samples were used for analysis of gene expressions. The specimens 1 month postoperatively were taken as the control, and the changes of expression of target genes over time were examined by real-time PCR. Results mRNA expression of Wnt1, Wnt2b, Wnt3a, β-catenin, Sfrp1, Lrp6, Lef1, CyclinD1, and Runx2 was up-regulated at 3 and 6 months compared with 1 month. The expression of Wnt5a, Sox9, and Osterix was up-regulated with a peak at 3 months, and then fell back to the basal levels at 6 months. The expression of Ocn began to up-regulate until 6 month postoperatively. Conclusion Our findings suggested that Wnt signaling was involved in the formation of traumatic TMJ bony ankylosis and thus may be a potential therapeutic target for the treatment of the disease in the future.

  • surgical induction of tmj bony ankylosis in growing sheep and the role of injury severity of the glenoid fossa on the development of bony ankylosis
    Journal of Cranio-maxillofacial Surgery, 2013
    Co-Authors: Yingbin Yan, Yi Zhang, Y H Gan, E Xiao
    Abstract:

    Abstract Objective The purpose of this paper is to summarize our experiences in creating an animal model of TMJ bony ankylosis based on 2 sequential experiments. Methods Two sequential experiments were performed with the aim of creating a model of TMJ bony ankylosis. Seven growing sheep were used in the first experiment, in which 1 was served as a control animal. Condylar Fracture with disc preservation was performed on the control side. On the contralateral side, Condylar Fracture, excision of the lateral 2/3 disc and injury to the glenoid fossa were performed to induce bony ankylosis. Three animals were sacrificed respectively at 3 and 6 months after surgery. In the second experiment, 7 growing sheep were used. The only difference of modeling between the 2 experiments was that more serious injury to the glenoid fossa was made in the ankylosis-induced side in experiment 2. Three, 2, and 2 animals were sacrificed respectively at 1, 3, and 6 months postoperatively. The TMJ complexes were examined by computed tomography (CT) and histological evaluation. Results In experiment 1, only fibrous ankylosis was observed in the ankylosis-induced side both at 3 and 6 months postoperatively. In experiment 2, CT and histological evaluation showed that the outcomes of the ankylosis-induced side were fibrous-bony ankylosis, fibrous-bony ankylosis, and bony ankylosis respectively at 1, 3, and 6 months after surgery. Conclusion Through summarizing the differences of the modeling and the different outcomes in the 2 experiments, we concluded that severe damage to the glenoid fossa played an important role in the development of TMJ bony ankylosis.

Y H Gan - One of the best experts on this subject based on the ideXlab platform.

  • a pilot trial on the molecular pathophysiology of traumatic temporomandibular joint bony ankylosis in a sheep model part ii the differential gene expression among fibrous ankylosis bony ankylosis and Condylar Fracture
    Journal of Cranio-maxillofacial Surgery, 2014
    Co-Authors: Yingbin Yan, E Xiao, Y H Gan, Yi Zhang
    Abstract:

    Abstract Objective The purpose of the study was to preliminarily explore the differential expressions of a series of genes regulating bone formation in temporomandibular joint (TMJ) fibrous ankylosis, bony ankylosis and Condylar Fracture healing. Methods The cDNA from either the bony ankylosed callus or Fracture callus of the 6 sheep, as described in the part I, were both used in the study. The differences of gene expressions between bony ankylosis and Condylar Fracture at 1, 3, and 6 months postoperatively were measured by real-time PCR, with 2 samples at each time point. In addition, another 2 sheep were added to have fibrous ankylosis induced on the right TMJ, and 1 sheep was sacrificed at 3 and 6 months after surgery, respectively. The differences of gene expressions between fibrous and bony ankylosis at 3 and 6 months postoperatively were measured by real-time PCR. Results Bony ankylosis showed higher mRNA expression trends in Wnt2b, Wnt5a, β-Catenin, Lef1, CyclinD1, Runx2, Osterix, Sox9, Col10a1, Alp, Ocn, Bmp2, and Bmp7 compared to fibrous ankylosis, although no statistical analysis was performed due to the very small sample size. Whereas bony ankylosis showed a significant lower expression of Wnt5a, β-Catenin, Lef1, Runx2, Osterix, Sox9, Col10a1, Alp, Ocn and Bmp4 compared to Condylar Fracture at several time points ( P Conclusion Our data provided a preliminary molecular evidence for the hypothesis that the development of traumatic TMJ bony ankylosis was the course of delayed bone healing or hypertrophic nonunion, and deserved to be further studied.

  • a pilot trial on the molecular pathophysiology of traumatic temporomandibular joint bony ankylosis in a sheep model part i expression of wnt signaling
    Journal of Cranio-maxillofacial Surgery, 2014
    Co-Authors: Yingbin Yan, E Xiao, Y H Gan, Yi Zhang
    Abstract:

    Abstract Objective To preliminarily investigate the temporal patterns of the endogenous mRNA expression for members of the Wnt signaling and a series of genes regulating bone formation during the development of traumatic temporomandibular joint (TMJ) bony ankylosis in a sheep model. Methods Six sheep were used for the induction of bony ankylosis of TMJ. We performed a Condylar Fracture, excision of the lateral 2/3 disc and serious injury to the glenoid fossa to induce bony ankylosis on the right TMJ. An isolated Condylar Fracture was performed on the left side. Two sheep were sacrificed at 1 month, 3 months, and 6 months after surgery, respectively. The specimens from the ankylosed joint and the Condylar Fracture were harvested for RNA extraction respectively. In this report (Part I), only the bony ankylosed samples were used for analysis of gene expressions. The specimens 1 month postoperatively were taken as the control, and the changes of expression of target genes over time were examined by real-time PCR. Results mRNA expression of Wnt1, Wnt2b, Wnt3a, β-catenin, Sfrp1, Lrp6, Lef1, CyclinD1, and Runx2 was up-regulated at 3 and 6 months compared with 1 month. The expression of Wnt5a, Sox9, and Osterix was up-regulated with a peak at 3 months, and then fell back to the basal levels at 6 months. The expression of Ocn began to up-regulate until 6 month postoperatively. Conclusion Our findings suggested that Wnt signaling was involved in the formation of traumatic TMJ bony ankylosis and thus may be a potential therapeutic target for the treatment of the disease in the future.

  • surgical induction of tmj bony ankylosis in growing sheep and the role of injury severity of the glenoid fossa on the development of bony ankylosis
    Journal of Cranio-maxillofacial Surgery, 2013
    Co-Authors: Yingbin Yan, Yi Zhang, Y H Gan, E Xiao
    Abstract:

    Abstract Objective The purpose of this paper is to summarize our experiences in creating an animal model of TMJ bony ankylosis based on 2 sequential experiments. Methods Two sequential experiments were performed with the aim of creating a model of TMJ bony ankylosis. Seven growing sheep were used in the first experiment, in which 1 was served as a control animal. Condylar Fracture with disc preservation was performed on the control side. On the contralateral side, Condylar Fracture, excision of the lateral 2/3 disc and injury to the glenoid fossa were performed to induce bony ankylosis. Three animals were sacrificed respectively at 3 and 6 months after surgery. In the second experiment, 7 growing sheep were used. The only difference of modeling between the 2 experiments was that more serious injury to the glenoid fossa was made in the ankylosis-induced side in experiment 2. Three, 2, and 2 animals were sacrificed respectively at 1, 3, and 6 months postoperatively. The TMJ complexes were examined by computed tomography (CT) and histological evaluation. Results In experiment 1, only fibrous ankylosis was observed in the ankylosis-induced side both at 3 and 6 months postoperatively. In experiment 2, CT and histological evaluation showed that the outcomes of the ankylosis-induced side were fibrous-bony ankylosis, fibrous-bony ankylosis, and bony ankylosis respectively at 1, 3, and 6 months after surgery. Conclusion Through summarizing the differences of the modeling and the different outcomes in the 2 experiments, we concluded that severe damage to the glenoid fossa played an important role in the development of TMJ bony ankylosis.

Susan M. Stover - One of the best experts on this subject based on the ideXlab platform.

  • biomechanical comparison of 3 0 mm headless compression screw and 3 5 mm cortical bone screw in a canine humeral Condylar Fracture model
    Veterinary and Comparative Orthopaedics and Traumatology, 2016
    Co-Authors: Mishka N Gonsalves, Daniel A Jankovits, Michael L Huber, Adam Strom, Tanya C Garcia, Susan M. Stover
    Abstract:

    Objective: To compare the biomechanical properties of simulated humeral Condylar Fractures reduced with one of two screw fixation methods: 3.0 mm headless compression screw (HCS) or 3.5 mm cortical bone screw (CBS) placed in lag fashion. Methods: Bilateral humeri were collected from nine canine cadavers. Standardized osteotomies were stabilized with 3.0 mm HCS in one limb and 3.5 mm CBS in the contralateral limb. Condylar fragments were loaded to walk, trot, and failure loads while measuring construct properties and Condylar fragment motion. Results: The 3.5 mm CBS-stabilized constructs were 36% stiffer than 3.0 mm HCS-stabilized constructs, but differences were not apparent in quality of Fracture reduction nor in yield loads, which exceeded expected physiological loads during rehabilitation. Small residual fragment displacements were not different between CBS and HCS screws. Small fragment rotation was not significantly different between screws, but was weakly correlated with moment arm length (R² = 0.25). Clinical significance: A CBS screw placed in lag fashion provides stiffer fixation than an HCS screw, although both screws provide similar anatomical reduction and yield strength to Condylar Fracture fixation in adult canine humeri.

  • prevalence location and symmetry of noncatastrophic ligamentous suspensory apparatus lesions in california thoroughbred racehorses and association of these lesions with catastrophic injuries
    Equine Veterinary Journal, 2016
    Co-Authors: Ashley E Hill, Ian A Gardner, Tim E Carpenter, Peta L Hitchens, Susan M. Stover
    Abstract:

    Summary Reasons for performing study Knowledge of the site distribution of ligamentous injuries facilitates clinical diagnosis of suspensory apparatus conditions. Objectives To determine if lesions within the suspensory ligament (SL) and distal ligaments of the proximal sesamoid bones (DSLs) were associated with suspensory apparatus failure or metacarpal lateral Condylar Fracture in California Thoroughbred racehorses. Study design Cross-sectional study. Methods Suspensory apparatus specimens from 327 deceased Thoroughbred racehorses were sectioned within the SL body and branches, and oblique and straight DSLs. Purple lesions ≥2 mm in width were categorised as moderate and paler or smaller lesions as mild. Associations between moderate lesions and age, sex, racetrack and cause of death were evaluated using multivariable logistic regression. Results Moderate lesions were evident in 16% and milder lesions in 77% of racehorses. Moderate lesions occurred with similar frequency in SL branches and oblique DSLs. Moderate lesions were more likely to occur in horses that died as a result of suspensory apparatus failure (odds ratio [OR] = 4.60; 95% confidence interval [CI] 1.61–13.13; and P = 0.004) or metacarpal lateral Condylar Fracture (OR = 5.05; 95% CI 1.42–17.93; and P = 0.012) compared with horses that died from nonmusculoskeletal causes, and in horses aged ≥7 years horses compared with 2-year-old horses (OR = 5.33; 95% CI 1.44–19.75; and P = 0.012). Conclusions Moderate lesions are common in the SL branches and oblique DSLs of racehorses, and may be associated with risk for suspensory apparatus failure and metacarpal Condylar Fracture. Monitoring health of the suspensory apparatus ligamentous structures may be a simple means of assessing fatigue in, and preventing more extensive injuries to, the forelimb suspensory apparatus and metacarpal condyles.

  • effects of injury to the suspensory apparatus exercise and horseshoe characteristics on the risk of lateral Condylar Fracture and suspensory apparatus failure in forelimbs of thoroughbred racehorses
    American Journal of Veterinary Research, 2004
    Co-Authors: Ashley E Hill, Ian A Gardner, Tim E Carpenter, Susan M. Stover
    Abstract:

    Objective—To assess concurrently the effects of moderate ligamentous suspensory apparatus injury (MLSAI), racing-speed exercise, and horseshoe characteristics on risk of catastrophic suspensory apparatus failure (SAF) or metacarpal Condylar Fracture (CDY) in forelimbs of racehorses. Sample population—Cadavers of 301 Thoroughbred racehorses (108 with SAF, 33 with CDY, and 160 control horses). Procedure—A cross-sectional epidemiologic study was used to describe distributions and relationships between MLSAI, exercise, and horseshoe variables. Logistic regression was used to assess potential risk factors for developing SAF and CDY. Results—Exercise variables were more highly associated with age than height of a steel bar affixed to the ground surface of the front of a horseshoe (ie, toe grab) or sex. Marginal associations were detected between MLSAI and age and height of toe grab. Higher risk for developing SAF was associated with MLSAI, use of a pad on a horseshoe, longer interval since last period of ≥ 60 d...

  • Biomechanical investigation of the association between suspensory ligament injury and lateral Condylar Fracture in thoroughbred racehorses.
    Veterinary surgery : VS, 2003
    Co-Authors: Sarah S. Le Jeune, Melinda H. Macdonald, Susan M. Stover, Kenneth T. Taylor, Max Gerdes
    Abstract:

    Objective-To determine whether partial transection of the medial branch of the suspensory ligament (MBSL) alters equine third metacarpal bone (MC3) Condylar surface strains and forelimb, distal joint angles in a manner consistent with promotion of lateral Condylar Fracture. Study Design-In vitro biomechanical experiment. Sample Population-Right forelimbs from 7 Thoroughbred horse cadavers. Methods-Lateral and medial MC3 Condylar, dorsal and abaxial, bone surface strains and distal joint angles were measured both before and after partial transection of the MBSL during in vitro axial limb compression. Dorsal, principal bone strains and abaxial, uniaxial, and proximodistal strains were compared before and after MBSL partial transection at 1,400-, 3,000-, and 5,600-N loads. Results-Bone strains increased in all locations with increasing axial load. All lateral Condylar bone strains were significantly higher, and abaxial surface medial Condylar bone strain was significantly lower, after partial transection of the MBSL. Respective distal joints became more flexed or extended as axial load increased but were not significantly different after partial transection of the MBSL. Conclusions-Partial transection of the MBSL increases in vitro MC3 lateral Condylar bone surface strains. Clinical Relevance-Loss of integrity of the medial branch of the suspensory ligament could increase the risk for lateral Condylar Fracture in Thoroughbred horses by amplifying bone strain in the lateral condyle.

  • a biomechanical comparison of equine third metacarpal Condylar bone fragment compression and screw pushout strength between headless tapered variable pitch and ao cortical bone screws
    Veterinary Surgery, 2002
    Co-Authors: Larry D Galuppo, Susan M. Stover, David G Jensen
    Abstract:

    Objectives— To compare bone fragment compression and the mechanical pushout strength and stiffness of 6.5-mm Acutrak Plus (AP) and 4.5-mm AO cortical (AO) bone screws after stabilization of a simulated equine third metacarpal (MC3) bone complete lateral Condylar Fracture. Study design— In vitro biomechanical paired study of screw insertion variables, bone fragment compression, and screw pushout tests using a bone screw stabilized simulated lateral Condylar Fracture model. Sample population— Six pairs of cadaveric equine MC3s. Methods— Metacarpi were placed in a fixture and centered on a biaxial load cell in a materials testing system to measure torque, compressive force, and time for drilling, tapping, and screw insertion. Fragment compression was measured with a pressure-sensing device placed between the simulated Fracture fragments during screw insertion for fragment stabilization. Subsequently, screws were pushed out of the stabilized bone fragments in a single cycle to failure. A paired t test was used to assess differences between site preparation, screw insertion, fragment compression, and screw pushout variables, with significance set at P < .05. Results— Measured drilling variables were comparable for AO and AP specimens. However, the AP tap had significantly greater insertion torque and force. Mean maximum screw insertion torque was significantly greater for AO screws. For fragment compression, AP screws generated 65% and 44% of the compressive pressure and force, respectively, of AO screws. AP screws tended to have higher overall pushout strength. Pushout stiffness was similar between both screw types. Conclusion— The 6.5-mm tapered AP screw generated less interfragmentary compressive pressure and force but had similar pushout stiffness. Evaluation of failure patterns demonstrated that AP screws had greater pushout strength compared with 4.5-mm AO screws for fixation of a simulated complete lateral Condylar Fracture. Clinical relevance— The 6.5-mm tapered AP screw should provide ample holding strength but would provide less interfragmentary compression than 4.5-mm AO screws for repair of complete lateral Condylar Fractures in horses.