计算机辅助设计和制造(CAD/CAM)的种植手术导板的应用

目的将计算机辅助设计和制造(CAD/CAM)种植手术的导板应用于种植手术,保证种植体植入在正确的位点和方向。方法按照导板制做的数据要求,用CT扫描患者的上下颌骨,在获取颌骨数据后输入种植导板设计的软件中,模拟种植体的位置和上部修复体,然后引导制造以修复为导向的准确的种植手术导板并在手术中应用。结果 16例患者采用计算机辅助设计引导制造的手术导板较好地完成了以修复为导向和最终获得良好位置的种植体的植入。结论计算机辅助设计和制造种植手术的导板能在术前了解患者颌骨的解剖结构和种植区骨量,确定术中种植的位点、控制植入的方向、缩短了手术时间,具有很好的应用前景。     

多牙缺失患者计算机导板应用下种植术后误差研究

目的评价分析计算机辅助设计和制作种植导板应用于多牙缺失患者的种植术后误差。方法选择多牙缺失患者20例,采集CT数据,利用彩立方Tooth Implant软件进行数据分析,拟定植入位点及确定手术计划并制作最终导板。口内戴入导板,植入种植体,选用相应型号的即刻修复基台,术后48 h内戴入即刻修复体。并于术后拍摄CT,测量术前、术后种植体在颌骨内的深度、近远中向及唇舌向的倾斜角度,计算术后误差,3个月后完成最终义齿修复。于修复后3个月、6个月及1年后评价种植体存留率。结果 20例多牙缺失患者共植入139枚种植体,种植体植入位置精确性好,观察期内有2枚种植体脱落,其余137枚种植体牙周软组织健康,无种植体周围炎发生。结论应用计算机辅助设计和制作的种植导板对于提高种植手术的质量与精度具有重要意义,可以指导临床医生植入种植体时避免伤及重要解剖结构,即刻修复极大地改善了患者术后生活质量,但仍需进一步跟踪观察其长期应用效果。     

多功能种植模板的制作及临床应用

介绍多功能种植模板的制作方法,模板结合放射技术,可以准确预测植入区骨量及相邻重要解总结构位置关系。方法：结合模型与导管导向技术,指导种植植入的位置和方向,作为临床性义齿,获取有关的咬合信息,指导种植上部结构的制作。结果“多功能模板为种植体的植入和修复提供了额 观依据,取得了较好的种植修复效果。结论模板制作简单,易于掌握,值得推广使用。     

热压成型模板在种植义齿修复中的应用

目的：了解热压成型模板在1～2个相邻种植体植入术中的指导效果一方法：利用热压成型机对薄塑胶板加热、真空加压，制作成带植入孔的外科模板，用该模板对1～2个相邻牙缺失的26例患者共32枚种植体的植入手术进行引导。在修复上部结构时，通过对基台及修复体的观察，了解种植体的位置及方向是否合适。结果：32枚种植体位置、方向均合适，并取得了较好的修复效果。结论：热压成型模板允许外科医生兼颐颌骨骨量，在修复要求的范围内对种植钻的方向作一定角度的调整，获得理想的种植体的位置和方向。该法制作简单，费用低。在1-2个相邻牙缺失的种植义齿修复中值得推广。     

计算机种植导板在斜向种植手术的应用

［摘要］ 目的 了解计算机种植导板在斜向种植手术的应用情况。方法 2011年2月—2014年1月之间,通过常规上下颌骨CT扫描,经计算机辅助制作软件建模,对13例上颌骨骨量不足种植病例,进行一定角度下斜向植入种植体而不需要进行上颌窦提升手术。共植入21颗种植体,均利用快速成型技术加工出个体化种植模板,并应用于该种植手术中。结果 在计算机种植导板的帮助下进行了斜向植牙,种植体植入术前设计位置实现了种植体的精确植入,能够在修复时与对颌牙形成良好的咬合关系,与术前设计方案基本一致。结论 该文利用计算机种植导板在进行上颌骨斜向植牙而非提升手术,可以很好的完成骨量不足区域的种植手术的定位及导向功能,是一种相对安全的选择性方案。     

SurgiGuide数字化黏膜支持式导板全程引导牙种植术的精确度研究

目的 探讨计算机辅助种植外科手术(computer assisted implantology,CAI)的精确度,对黏膜支持式导板全程引导的种植手术的误差进行分析.方法 选取接受CAI的无牙颌患者9例,共植入63枚种植体(27枚植入在上颌,36枚植入在下颌).9例患者术前均制作放射导板并采用双扫描技术(Dual-Scan)拍摄CBCT,即患者佩戴放射导板进行CBCT检查及放射导板单独拍摄CBCT,并将所得数据以DICOM格式导出,再将该数据导入到Simplant软件中并进行种植体术前虚拟设计,设计结果和患者口腔硬石膏模型发往Materi-alise公司(Belgium)制作SurgiGuide黏膜支持式手术导板,在导板全程引导下完成种植体的植入,术后再次获取患者颌骨及种植体的CBCT数据,应用Simplant软件对种植体术前虚拟设计位置和术后实际位置进行匹配,获取术前、术后种植体肩部、根尖部、角度以及深度4项误差距离.结果 63枚种植体术后随访6个月至10年,留存率为100%,肩部的平均误差为(0.73±0.53)mm;根部的平均误差为(1.16±0.62)mm;深度的平均误差为(0.95±0.64)mm;种植体角度的平均误差为4.10° ±3.23°.结论 SurgiGuide黏膜支持式种植导板引导的种植手术存在一定误差,术前设计时应将误差结果考虑在内,以避开重要的解剖结构来保证手术安全,术中要正确操作以减少种植体植入的误差.     

种植外科手术定向模板的制作及临床应用

目的：介绍一种种植外科手术定向模板的制作,初步评价其在1～2个相邻种植体植入术中的指导作用。方法：利用种植体把持器在研究模型上确定种植体植入方向及位置,采取空气压膜技术制作成带植人隧道的外科模板,用该模板对1～2个相邻牙缺失的20例患者共27枚种植体的植人手术进行引导。结果：32枚种植体位置、方向均合适,并取得了较好的修复效果。结论：该种植外科手术定向模板在1～2个相邻牙缺失的种植义齿修复中可获得理想的种植体的位置和方向。该法制作简单,费用低,尤其对初学者值得推广。     

计算机辅助制作外科模板在眶部种植手术中的临床应用

目的:了解计算机辅助制作的个体化外科模板在眶部种植术中定位及导向的指导效果.方法:通过常规眶部CT扫描,经计算机辅助制作软件建模,利用快速成型技术加工出个体化外科模板,应用于眶部种植术中,完成准确定位及导向功能.结果:利用个体化外科模板,完成了3例眶部缺损患者的种植手术,共植入10颗种植体,术中未出现并发症,种植体植入术前设计位置,实现了种植体的精确植入.结论:利用计算机辅助软件及快速成型技术制作的个体化外科模板可以很好的完成眶部种植术中定位及导向功能,在眶部种植手术中值得推广应用.     

计算机种植导板在重度吸收上颌窦患者进行种植提升手术的应用

目的:了解计算机种植导板在重度吸收上颌窦患者进行种植提升手术的应用情况。方法:2007年1月至2009年3月之间,通过常规上下颌骨CT扫描,经计算机辅助制作软件建模,12例上颌窦区域骨质重度吸收的患者,共19颗牙植体,利用快速成型技术加工出个体化种植模板,并按照轴向垂直载荷的力学原则进行了反咬合设计,应用于上颌窦的种植术中。结果:在计算机种植导板的辅助下,种植体植入术前设计位置实现了种植体的精确植入,能够在修复时与对颌牙形成良好的咬合关系,完全实现了手术前进行的反咬合设计方案。术中未出现并发症。结论:利用计算机种植导板技术,在进行上颌窦植牙时,尤其是在上颌窦颊侧壁重度吸收的情况下,对于非常规的反咬合设计,可以很好的完成上颌窦种植术的定位及导向功能。     

模板定向在牙种植中的应用

采用模板定向对８０例患者植入１０８枚种植体，较好解决了种植体植入位置、方向准确的问题。经１年的观察，使用模板定向种植临床成功率９５％。结果表明模板定向使植入的种体能准确达到术前的预定位置，有利于手术中综合考虑解剖条件和修复要求。     

正常人群下颌管的三维定位测量研究

目的：应用CT进行下颌管的三维定位测量研究,为牙种植术等提供临床解剖学依据。方法：对50例正常人下颌骨进行螺旋CT扫描,在预定截面上测量下颌管至颊、舌、牙槽嵴顶以及下颌骨下缘的距离,测量结果采用SPSS13.0软件进行统计学分析。结果：下颌骨左右两侧各组测量结果无显著性差异;下颌管至舌侧骨板的距离比下颌管外缘至颊侧骨板距离小,两者差异有显著性（P〈0.05）;下颌管上缘至牙槽嵴顶的距离较下颌管下缘至下颌骨下缘的距离大,两者差异有显著性（P〈0.05）。结论：下颌管在下颌骨后牙区走行中偏向舌侧骨板,而且距离下颌骨下缘较近。当下颌骨的垂直高度不足时,下颌管的颊舌向位置就十分重要,第二磨牙区种植一般伤及下牙槽神经的风险较小。     

牙种植体植入方向在修复设计与颌骨骨量间的差异

目的 测量颌骨不同区域修复设计要求的牙种植体植入方向（PPT）与颌骨骨量允许的植入方向（RBT）间的差异。方法 在30例患者的85个种植部位上，制作带有放射标识物的放射模拟，以确定修复设计要求的种植方向。通过螺旋CT的斜位多平面重建功能（obique-MPR）获取种植区放射标示物所在部位的颌骨横断面影像，测量PPT和RBT间的角度差异。结果 二者间角度差异在下颌磨牙区最大。结论 二者间角度差异的测定有助于口腔外科、修复科生协同制定最佳的种植手术方案。     

Evaluation of maxillary incisive canal characteristics related to dental implant treatment with computerized tomography: a clinical multicenter study

Background: A close anatomic relationship between the incisive canal and the roots of the central maxillary incisors should be kept in mind during dental‐implant treatment in the anterior maxilla. The aim of the present study is to analyze incisive canal characteristics on computed tomography (CT) sections and to evaluate its relation to bone anterior to the canal with regard to dental implantation. Methods: A total of 933 partially edentulous and/or edentulous patients scheduled for implant insertion in four dental clinics enrolled in the present study. The following were measured and recorded from CT sections for analysis: 1) diameter and length of the incisive canal; 2) width and length of the bone anterior to the canal; 3) palatal bone width and length; and 4) root width and length of the central incisor. Results: Mean canal length was 10.86 ± 2.67 mm, and mean diameter was 2.59 ± 0.91 mm. Canal length was shortened in edentulous anterior maxilla compared to dentate maxilla. However, canal diameter did not show any difference between dentate and edentulous groups. Males had a longer and wider incisive canal than females. Canal shape was mostly cylindrical in 40.73% of images. No correlation was found with mean canal length and mean canal diameter according to age. Conclusions: Although variations exist in every patient, the findings from this study suggest that sex and dental status are important factors that can affect incisive canal characteristics and amount of bone anterior to the canal. Clinicians should perform careful planning using CT scans before performing dental implant surgeries in premaxillary region.     

跨下颌神经管种植在萎缩下颌后牙区的应用

目的：探讨在下颌后牙缺失骨高度严重不足时,采用超声上颌窦内提升骨刀制备种植窝,进行偏颊侧跨下牙槽神经种植的可行性。方法：11例下颌后牙缺失患者,牙槽嵴顶至下颌神经管上缘距离3.2-5.5mm,按照手术导板偏颊侧倾斜角度,常规制备种植窝至下颌神经管上端1mm处,再用超声内提升骨刀头从已备种植床中央向下方跨过下牙槽神经继续备洞至植入长度,共植入种植体25颗;术中及术后当天密切观察种植床出血及下唇感觉,负载后1、3、6、9、12个月定期复查。结果：术中均未损伤下牙槽神经;观察期间种植体稳固无一脱落,种植体周围牙龈组织健康,种植体周围未见骨低密度影,负载后12月种植体边缘骨高度与刚负载时边缘骨高度差异无统计学上意义;咀嚼功能恢复满意。结论：应用超声上颌窦内提升骨刀,进行跨下颌神经管种植是一种安全、简单、可靠的修复下颌后牙缺失骨高度严重不足的方法,可避免使用传统的外置法植骨、牵张成骨术、下牙槽神经移位术。     

Spiral tomography for measuring bone width at different levels from the crest to the inferior border of the mandible in vitro

Introduction Tomography images provide sufficient detail for estimating the vertical and horizontal dimensions of alveolar bone and reducing surgical injuries. This study evaluated the role of spiral tomography in measuring mandibular alveolar bone width. Methods Cross-sectional tomography slices were taken using a Cranex Tome unit at three or four different locations on each side of three chosen mandibles, such that all the locations were distal to the mental foramen. In addition, artificial soft tissues were reconstructed using Play-Doh modeling clay. On the tomography image, a line was drawn from the crest to the inferior border of the mandible (MC), and the bone height to the mandibular canal and bone width were measured at one-third, two-thirds, and one-half MC, and the mandibular canal levels. Then, the mandibles were sectioned at the same sites, and the bone sections were measured. For statistical analysis, the sign test analysis was used. Results There was a statistically significant difference between the tomographic and real anatomical bone width at one-half and one-third MC, and the canal level (P < 0.05), while the difference between tomography and bone section measurements were not significant at two-thirds MC, or, the bone height to the mandibular canal (P > 0.05). Conclusions The bone width on tomographic images was overestimated by between 2.3 and 0.1 mm. Therefore, caution should be exercised when evaluating bone width measured from tomography images. In most locations, the measured height to the canal was underestimated by between 0.1 and 2.7 mm, which confirmed the safety of spiral tomography for estimating the distance related to the mandibular canal.     

Analysis of Occlusal Stresses Transmitted to the Inferior Alveolar Nerve by Multiple Threaded Implants

Background : Potential nerve injury or loss of sensation can occur after mandibular implant placement or loading. To avoid this type of damage, it is critical to determine the proper distance from implants to the mandibular nerve. Hence, the purpose of this study is to use biomechanical analyses to determine the safe distance from multiple implants to the inferior alveolar nerve. Methods: Using the boundary element method, a numerical mandibular model was designed to simulate a mandibular segment containing multiple threaded fixtures. This model allows assessment of the pressure, as induced by occlusal loads, on the trigeminal nerve. Such pressure distribution was evaluated against different distances from the fixtures to the mandibular canal, against the possible lack of the central fixture in a three‐abutment configuration, and against different levels of implant osseointegration. All the simulations considered a canal that is orthogonal to the implant axis. Results: Nerve pressure increased quickly when the implant–canal distance decreased in the range studied. Lack of the central implant to support the central abutment caused major increases in nerve pressure. Conclusions: This study suggests a minimal implant–canal distance of 1 mm to prevent inferior alveolar nerve damage caused by three connected implants. For clinical safety, an additional 0.5 mm is recommended as a cushion, so a 1.5‐mm minimal distance should be planned to avoid potential nerve injury.     

下颌管的走行及解剖结构的研究

目的　研究下颌管的位置及解剖结构 ,为种植牙提供解剖依据。方法　选 15具成人有牙下颌骨标本在特定截面上测量下颌管纵横径和四壁厚度 ,观察 4具动脉灌注新鲜标本的下颌管内血管神经之间的关系。结果　下颌管在下颌骨体部走行中偏舌侧 ,并近下颌骨下缘 ;管内血管位于神经之上。结论　牙种植术中按正常解剖方位钻孔 ,可避免损伤下牙槽神经。如术中下颌管内突然涌出大量新鲜血 ,则提示继续手术可能损伤下牙槽神经     

Correlation between planned prosthetic and residual bone trajectories in dental implants

STATEMENT OF PROBLEM: The success of dental implant treatment relies on a well-developed treatment plan approach. Historically, implant placement was guided mainly by residual bone height and width, at times compromising prosthetic needs. PURPOSE: This study analyzed the amount of deviation between planned prosthetic trajectory and residual bone trajectory in different areas of the maxillary and mandibular dental arches, by using a tomographic survey in conjunction with imaging/surgical guides. METHODS AND MATERIAL: Ninety-two patients with a total of 235 implant sites were selected for the study. An imaging and surgical guide with a radiopaque indicator was constructed to determine the planned prosthetic trajectory. Cross-sectional tomograms were taken through the indicator at each implant site. The outlines of the available bone, planned prosthetic trajectory, and residual bone trajectory were traced, and the difference in the trajectory between the 2 trajectories was determined. RESULTS: Discrepancies between the planned prosthetic and the residual bone trajectories were greater in the mandibular molar area. This site was statistically different from other site groups at P =.05 (Tukey method). Statistically, all other site groups were not significantly different.     

Clinical application of a new cone-beam computerized tomography system to assess multiple two-dimensional images for the preoperative treatment planning of maxillary implants: case reports.

Accurate assessment of the location of the maxillary sinuses, incisive canal, and nasal cavity, as well as the height, width, and angulation of bone is essential for implant treatment planning. The purpose of this study was to introduce the clinical application of a cone-beam computerized tomography system (Ortho-CT) to assess multiple two-dimensional (2D) images for the preoperative treatment planning of maxillary implants. To evaluate the multiple 2D images scanned using the Ortho-CT system the maxillary region placed with radiopaque template in the maxilla. Ortho-CT images provided useful information for evaluating the morphology of the maxilla, for locating the incisive canal, maxillary sinuses, nasal cavity, and for showing the relationship of the template to the bone. It is concluded that the Ortho-CT system is a useful aid for diagnosis and treatment planning for maxillary implant treatment.     

Dental implant primary stability in different regions of the Jawbone: CBCT-based 3D finite element analysis

AimThis study aimed to analyze the primary stability of dental implant in maxillary and mandibular anterior and posterior regions using a finite element analysis.Materials and methodsCBCT images of maxillary and mandibular regions were collected from patients’ radiographic data and transformed to 3D models. A Straumann Dental implant was inserted in each bone model and then pulled-out, where amount von-Mises stress was obtained and analyzed for each. A comparison between the insertion and the pull-out was evaluated.ResultsTwenty-four images were randomly selected for analysis from 122 scans. In both the insertion and the pull-out of the dental implant, von-Mises stress was high in cortical as compared to the cancellous bone (p < 0.0001). Maxillary posterior region had a low von-Mises stress (p < 0.001). Bone plastic deformation was higher in cancellous than the cortical bone in all bone regions and was the lowest in maxillary posterior region (p < 0.001). Bone displacement decreased from Type I to type IV bone.ConclusionEvaluation of von-Mises stress showed different measurements in maxillary and mandibular regions. Bone deformation was low in the maxillary posterior region.