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Neil R Crawford - One of the best experts on this subject based on the ideXlab platform.
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biomechanical evaluation of the craniovertebral junction after anterior unilateral Condylectomy implications for endoscopic endonasal approaches to the cranial base
Neurosurgery, 2013Co-Authors: Luis Perezorribo, Andrew S Little, Richard D Lefevre, Phillip R Reyes, Anna G U S Newcomb, Daniel M Prevedello, Hector Roldan, Peter Nakaji, Curtis A Dickman, Neil R CrawfordAbstract:BACKGROUND : Endoscopic endonasal approaches to the craniovertebral junction and clivus, which are increasingly performed for ventral skull base pathology, may require disruption of the occipitocondylar joint. OBJECTIVE : To study the biomechanical implications at the craniovertebral junction of progressive unilateral Condylectomy as would be performed through an endonasal exposure. METHODS : Seven upper cervical human cadaveric specimens (C0-C2) underwent nondestructive biomechanical flexibility testing during flexion-extension, axial rotation, and lateral bending at C0-C1 and C1-C2. Each specimen was tested intact, after an inferior one-third clivectomy, and after stepwise unilateral Condylectomy with an anterior approach. Angular range of motion (ROM), lax zone, and stiff zone were determined and compared with the intact state. RESULTS : At C0-C1, mobility during flexion-extension and axial rotation increased significantly with progressive Condylectomy. ROM increased from 14.3 ± 2.7° to 20.4 ± 5.2° during flexion and from 6.7 ± 3.5° to 10.8 ± 3.0° during right axial rotation after 75% condyle resection (P 75% anterior Condylectomy.
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stability of the craniovertebral junction after unilateral occipital condyle resection a biomechanical study
Journal of Neurosurgery, 1999Co-Authors: A G Vishteh, Neil R Crawford, M S Melton, R F Spetzler, Volker K H Sonntag, Curtis A DickmanAbstract:Object. The authors sought to determine the biomechanics of the occipitoatlantal (occiput [Oc]—C1) and atlantoaxial (C1–2) motion segments after unilateral gradient Condylectomy. Methods. Six human cadaveric specimens (skull with attached upper cervical spine) underwent nondestructive biomechanical testing (physiological loads) during flexion—extension, lateral bending, and axial rotation. Axial translation from tension to compression was also studied across Oc—C2. Each specimen served as its own control and underwent baseline testing in the intact state. The specimens were then tested after progressive unilateral Condylectomy (25% resection until completion), which was performed using frameless stereotactic guidance. At Oc—C1 for all motions that were tested, mobility increased significantly compared to baseline after a 50% Condylectomy. Flexion—extension, lateral bending, and axial rotation increased 15.3%, 40.8%, and 28.1%, respectively. At C1–2, hypermobility during flexion—extension occurred after a ...
Goh Bee Tin - One of the best experts on this subject based on the ideXlab platform.
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osteochondroma of the mandibular condyle report of two surgical approaches
annals of maxillofacial surgery, 2014Co-Authors: William Lim, Lye Kok Weng, Goh Bee TinAbstract:Osteochondromas are common tumors of the long bones, but are rare in the craniofacial region. We detailed two different management of osteochondroma of the mandibular condyle treated utilizing three-dimensional (3D) imaging and computer-assisted planning. Simultaneous open temporomandibular joint and orthognathic surgeries were done to treat both the pathology and secondary facial asymmetry. An osteochondroma that presented as a bony mass at the lateral aspect of the left mandibular condyle of a 24-year-old Chinese female was treated with simultaneous orthognathic surgery and conservative excision. No recurrence was detected 7 months postsurgery. An osteochondroma that presented as a generalized enlargement of the right mandibular condyle of a 25-year-old Chinese male was treated with simultaneous orthognathic surgery and Condylectomy. There were no significant issues 3 years postsurgery. Simultaneous orthognathic and temporomandibular joint surgeries are a viable option for the management of osteochondroma of the mandibular condyle. The availability of 3D imaging enabled better presurgical examination of the lesion, which directed treatment toward Condylectomy or conservative excision.
R Farina - One of the best experts on this subject based on the ideXlab platform.
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minimally invasive intraoral proportional Condylectomy with a three dimensionally printed cutting guide
International Journal of Oral and Maxillofacial Surgery, 2020Co-Authors: O L Haas, R Farina, Federico Hernandezalfaro, R B De OliveiraAbstract:The aim of this study was to describe the steps of a minimally invasive surgical technique used to perform a proportional intraoral Condylectomy with a three-dimensionally (3D) printed cutting guide. The technique consists of two steps: virtual surgical planning and intraoral Condylectomy. During virtual surgical planning, the mandibular ramus was measured bilaterally, the height of the proportional Condylectomy was planned virtually, and a cutting guide was 3D printed. In the intraoral Condylectomy, the mandibular condyle was approached intraorally, the 3D printed cutting guide was positioned in the sigmoid notch, and the proportional Condylectomy was performed. The protocol reported in this technical note is the sum of knowledge acquired from a series of studies published previously by the authors, who have jointly developed a surgical technique that is both minimally invasive and accurate for the treatment of condylar hyperplasia.
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three dimensional skeletal changes after early proportional Condylectomy for condylar hyperplasia
International Journal of Oral and Maxillofacial Surgery, 2019Co-Authors: R Farina, E Moreno, J Lolas, F Silva, Benjamin MartinezAbstract:The purpose of this study was to evaluate volumetric and dentoskeletal changes in 21 patients with active unilateral condylar hyperplasia (AUCH) after proportional Condylectomy. A split-mouth design was used: control group healthy joints (HS, healthy side) and test group affected joints (AS, affected side) (21 per group). Cone beam tomography scans were obtained at T0 (preoperative), T1 (10days after the intervention), and T2 (approximately 12 months post-surgery). The condylar unit volume (CUV), articular cavity volume (ACV), and dentoalveolar units (DAUs) were measured. CUV showed a difference of 1.12cm3 between T0 and T1, increasing 0.4cm3 between T1 and T2 on AS. There was no difference between T0 and T2 on HS. ACV increased 0.65cm3 between T0 and T1 on AS, after which it decreased by 0.36cm3 at T2 (0.30cm3 larger than the initial articular cavity at T0). ACV showed no post-surgery differences on HS. Midline DAU showed extrusion of 0.20mm for maxilla and 0.52mm for mandible, while in the lateral area, maxilla was extruded by 0.3mm on HS and was intruded 0.12mm on AS. For the mandible, both sides showed extrusion (0.4-0.6mm). In the distal to canine and molar areas, intrusion of 0.2mm and 0.9mm, respectively, was observed on AS; there was extrusion of 0.6mm distal to the canine on HS. At the mandibular level, AS distal to the canine showed extrusion of 1mm, while intrusion of 0.2mm was observed in the molars. For HS, only extrusion at the molar level (0.2mm) was observed. In conclusion, after proportional Condylectomy, a neocondyle forms within 12 months to equal the healthy contralateral side. The articular cavity, which is reduced in the initial stage, increases in size after surgery and the volume gradually approaches that of the healthy side. Dentoalveolar changes occur at the anterior and posterior levels, causing intrusion and extrusion of the interdental crests. An early proportional Condylectomy as the sole surgical treatment for patients with AUCH allows normalization of the maxillomandibular relationship.
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high Condylectomy versus proportional Condylectomy is secondary orthognathic surgery necessary
International Journal of Oral and Maxillofacial Surgery, 2016Co-Authors: R Farina, Sergio Olate, Juan Pablo Alister, A Raposo, I Araya, Francisca UribeAbstract:The objective of this study was to assess the need for secondary orthognathic surgery in patients undergoing two different Condylectomy protocols for active unilateral condylar hyperplasia (UCH). A retrospective cohort study evaluated UCH patients treated by Condylectomy. Two groups were established: group 1 comprised those who had undergone a high Condylectomy (5 mm removed) and group 2 comprised those who had undergone a proportional Condylectomy (removing the difference observed between the measurements of the hyperplastic and the healthy side). Data analysis was done with the Levene test and t-test; a P-value of <0.05 indicated a statistically significant relationship. Forty-nine patients, with an average age of 19.83 years, were analyzed; 11 were included in group 1 and 38 in group 2. There was no statistical difference between the two groups with regard to age or sex (P=0.781). An average of 5.81 mm was removed in the high Condylectomy group, while an average of 9.28 mm was removed in the proportional Condylectomy group; this difference was statistically significant (P=0.042). Comparing the two groups, proportional Condylectomy reduced the need for secondary orthognathic surgery (P<0.001). The proportional Condylectomy can be used as the sole surgical treatment in cases of UCH, thus avoiding the need for secondary orthognathic surgery.
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low Condylectomy as the sole treatment for active condylar hyperplasia facial occlusal and skeletal changes an observational study
International Journal of Oral and Maxillofacial Surgery, 2015Co-Authors: R Farina, F Pintor, J Perez, Roberto Pantoja, D BernerAbstract:The purpose of this study was to measure the changes in facial, occlusal, and skeletal relationships in patients with active unilateral condylar hyperplasia whose sole treatment was a low Condylectomy. A retrospective observational descriptive study was conducted. All patients had undergone a low Condylectomy as the sole or initial surgical treatment. The size of the condylar segment removed was decided by matching the affected side with the healthy side, leaving them both like the healthy one. The length of the ramus was measured using panoramic X-ray (distance from the highest part of the condyle to the mandibular angle). Facial, occlusal, and skeletal changes were evaluated using clinical, photographic, and radiological records before and after surgery. Condylectomy as the sole treatment for patients with active condylar hyperplasia allowed improvements to the alterations produced by this pathology, such as chin deviation, tilted lip commissure plane, tilted occlusal plane, angle of facial convexity, unevenness of the mandibular angles, and length of the mandibular ramus. The occlusal relationship also improved with orthodontic and elastic therapy. To conclude, low Condylectomy as a sole and aetiological treatment for patients with active condylar hyperplasia allowed improvements to alterations produced by this pathology.
Rosana Martinezsmit - One of the best experts on this subject based on the ideXlab platform.
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Condylectomy and surgery first approach an expedited treatment for condylar hyperplasia in a patient with facial asymmetry
Dental Press Journal of Orthodontics, 2017Co-Authors: Diego Fernando Lopez, Juan Fernando Aristizabal, Rosana MartinezsmitAbstract:Condylar Hyperplasia (CH) is a self-limiting pathology condition that produces severe facial deformity at the expense of mandibular asymmetry. In this case report a 15-year-old female patient was diagnosed with Unilateral Condylar Hiperplasia (UCH) by mean of single-photon emission computed tomography (SPECT) and histological study. A high Condylectomy in the right condyle was performed to stop the active status of the hyperplasia. A month after Condylectomy, orthognathic jaw impaction and asymmetric mandibular setback surgery was performed with the Surgery First Approach (SFA). After 10 days, orthodontic appointments were made every two weeks during 4 months. The active phase of treatment lasted 14 months. Excellent facial and occlusal outcomes were obtained and after 24 months in retention the results remained stable.
Belmiro Cavalcanti Do Egito Vasconcelos - One of the best experts on this subject based on the ideXlab platform.
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efficacy of proportional versus high Condylectomy in active condylar hyperplasia a systematic review
Journal of Cranio-maxillofacial Surgery, 2019Co-Authors: Tania Camila Ninosandoval, Francisco Paulo Araujo Maia, Belmiro Cavalcanti Do Egito VasconcelosAbstract:Abstract Objective To perform a systematic literature review to test the efficacy of proportional Condylectomy versus high Condylectomy in patients with active condylar hyperplasia, in terms of avoiding secondary surgeries. Method Following a search of Medline (Pubmed), Embase, Scopus, Web of Science and Cochrane databases, ten studies were included for qualitative analysis, and two studies were included for meta-analysis. Quality assessment was performed using the Newcastle–Ottawa scale for cohort studies and the 18-item modified Delphi technique for case series. Results 259 patients were included in the qualitative analysis, with a weighted arithmetic mean age of 20.4 years, and a female:male ratio of 2:1. Meta-analysis was carried out for 52 patients, and it was found that proportional Condylectomy reduced the need for secondary surgery (p = 0.0003). Although this evidence had limitations, excised bone on proportional Condylectomy was superior when compared with excised bone on high Condylectomy, re-establishing the occlusal plane, resulting in fewer asymmetries, and therefore reducing the need for further surgery. Conclusions This systematic review showed a tendency for proportional condylectomies to avoid additional surgeries; however, more comparative studies are necessary.