无牙颌金属种植导板精度分析的病例系列

目的 通过系列病例分析金属导板引导的无牙颌种植中种植体的植入精度。方法 术前拍摄CBCT获取三维数据，在设计软件内拟合数据后进行种植导板设计，通过三维打印的方式制作钛金属导板，试戴后引导种植手术。对比5例全口或半口无牙颌种植的35颗种植体术前设计与术后实际位置的偏差，分析金属导板的精度。结果 排除5颗半程引导、1颗颧种植、4颗上颌窦底提升部位种植的种植体后，最终纳入25颗种植体。所有病例未发生导板折裂，种植体均愈合良好，未见骨灼伤等情况。精度分析结果显示：在近远中向上，种植体尖端水平位移0.91(0.28-1.35)mm，颈部水平位移0.46(0.23-0.83)mm，尖端垂直位移0.57(0.29-0.80)mm，角度偏差1.93°（1.02°-3.40°）；在颊舌向上，种植体尖端水平位移0.84(0.43-1.51)mm，颈部水平位移0.77(0.32-1.05)mm，尖端垂直位移0.52(0.30-0.88)mm，角度偏差2.77°（2.09°-4.21°）。结论 在本研究有限的无牙颌种植手术病例系列中，金属导板得到了与树脂导板相似的精度和临床效果。     

数字化导板辅助种植6颗平行种植体精确度分析

目的 通过对比3种数字化测量方法,评估静态导板辅助种植的精确度并探讨同一导板辅助种植多颗种植体的影响误差及种植体之间的平行情况。方法 随机抽取3名下颌无牙颌患者的CBCT数据,数据提取后通过Straumann P20+3D打印机仿形态各打印10个模型,共30个下颌无牙颌树脂模型。按照无牙颌固定修复在46位点、44位点、42位点、32位点、34位点、36位点常规植入6颗平行种植体,并设计手术导板。由1名种植医生从46位点开始依次顺序种植6颗种植体,共180颗种植体,术后分别用3种测量方法评估植入种植体的3D距离偏差及轴向角度偏差。结果 术后种植体合计平均角度偏差为1.89°±0.87°,平均3D距离偏差颈部为（0.46±0.19）mm、根方为（0.58±0.21）mm;扫描杆&Qualify、扫描杆&coDiagnostiX和CBCT&coDiagnostiX 3种测量方法的测量数据轴向角度偏差分别为1.96°（1.26°）、1.82°（1.15°）和1.60°（1.12°）,颈部3D距离偏差分别为0.37mm(0.23mm)、0.41mm(0.15mm)和0.6...     

CAD／CAM导板在上颌后牙种植修复中的临床应用研究

目的：评价基于临床CT数据的计算机辅助设计和制造（computer aided design／computer aided manufacture,CAD／CAM）导板在上颌后牙种植修复中的定位精度。方法：通过对16例患者上颌骨进行CT扫描,基于CT数据设计和制作黏膜支持式CAD／CAM种植导板,并在种植导板辅助下于缺牙区不翻瓣植入20枚柱状软组织水平种植体,再次行CT扫描,采用点对点配准技术实现扫描前后的CT三维重建模型配准,测量实际种植体位最与虚拟放置种植体位置问的偏离值。结果：在CAD／CAM种植导板辅助下,20枚种植体平均头部偏差量为1．19mm±0．02mm,颊舌向和近远中向以及胎龈向偏离值分别为0．53mm±0．04mm、0．42mm±0．03mm和0．30mm＋0．04mm。尾部偏差量为1．03mm±0．06mm,角度偏差量为0．73°±0．64°。经统计学检验,种植体头部偏离值在颊舌向、胎龈向的偏离值无统计学差异（P〉0．05）;而在近远中向的偏离值较其他2个方向略大,其差异有统计学意义（P〈0．05）。但是,种植体头部偏离值分别在颓舌向、近远中向、胎龈向偏离值都无统计学差异（P〉0．05）。结论：在CAD／CAM导板辅助下,上颌后牙区植入种植体精度较高;种植导板对种植体植入后的整体角度偏离影响较为明显;并且在三维方向上种植体头部在近远中方向的偏离对整体头部的偏离影响较大。     

CAD/CAM导板在后牙区种植精度的体外研究

目的 后牙区利用计算机辅助设计和制作（computer aided design and computer aided manufacture,CAD/CAM）导板种植时,比较翻瓣与不翻瓣两种术式的精度。方法 选取20名后牙种植患者的锥形束CT（cone beam CT,CBCT）资料和石膏模型,采用3D打印技术制作翻瓣与不翻瓣树脂模型,运用导板在两种模型上模拟牙种植术,分别计算术前术后种植体位置偏差进而比较两种术式的精度。结果 CAD/CAM导板在后牙区辅助种植时,翻瓣与不翻瓣术式种植体顶端偏差分别为（0.95±0.36）mm、（1.33±0.43）mm;底端偏差分别为（1.53±0.56）mm、（1.94±0.30）mm;角度偏差分别为3.45°±1.10°、3.31°±1.55°;深度偏差分别为（0.75±0.47）mm、（1.43±0.41）mm。翻瓣与不翻瓣两种术式在种植体距离偏差上有统计学差异,角度偏差上没有统计学差异。结论 CAD/CAM导板引导的种植翻瓣术式比不翻瓣术式在种植体距离偏差上更准确。     

分置式可测量种植导板在多颗前牙即刻种植即刻修复中的应用

本文报道1例应用分置式可测量种植导板引导的即刻种植即刻修复技术,修复牙外伤所致的12—22牙缺失。术前根据咬合记录,在exoCAD软件中设计上部目标修复体空间轮廓位置,再通过口内和锥形束CT图像实测获得12—22牙位点近远中向、唇腭向和𬌗龈向分别在软硬组织水平的空间数据,在Bluesky Plan 4软件中设计比选4个正确种植位点,确认后设计并通过三维打印制作基于三向位置数值的可测量种植导板。术中使用3组可测量种植导板结合测量尺实测依次完成定点、半钻预备及轴向核查、全程预备及三向位置核查和种植体植入,之后再次实测核查种植位点。术后通过转移导板即刻戴入基于目标修复体空间和原天然牙穿龈形态设计、并于术前切削完成的临时修复体。经术后对比测量,种植入口点平均线性偏差为（0.57±0.17）mm,种植止点平均线性偏差为（0.82±0.27）mm,各植体平均角度偏差为（1.86±0.89）°,实现了12—22牙位点种植体的精准植入与同期的即刻修复。     

口腔种植机器人在前牙区即刻种植中的精度分析

目的 探究自主式种植机器人辅助前牙区即刻种植手术的精度。方法 按照标准纳入前牙区需行即刻种植的病例10例，共10个种植位点。按照口腔种植机器人的规范操作流程进行种植体窝洞预备和植入，术后患者再次拍摄CBCT，利用机器人导航软件评估实际植入位点与设计位点间的偏差。结果 种植体颈部平均总偏差为（0.86±0.40）mm，横向偏差为（0.69±0.36）mm，深度偏差为（0.28±0.57）mm；种植体根尖平均总偏差为（0.98±0.49）mm，横向偏差为（0.81±0.49）mm，深度偏差为（0.29±0.58）mm，总体角度偏差为1.09°±0.61°。结论 自主式机器人辅助前牙区即刻种植精度高，能获得满意的临床效果。     

牙支持式数字化导板在牙种植中的临床应用效果

目的 :评估使用牙支持式数字化外科导板引导进行上颌、下颌、前牙、后牙区种植的精准度。方法 :术前经过锥形束CT(CBCT)获得缺牙区颌骨数据信息,扫描上下颌石膏模型获得颌骨数字化模型。采用种植设计软件完成导板的设计,通过快速成型技术完成种植手术导板的制作。在导板引导下完成种植手术。术后拍摄CBCT,将该CBCT数据导入种植设计软件,与术前种植设计数据进行整合后测量种植体位置与术后实际位置的差异。结果:上颌、下颌、前牙、后牙区1～2颗牙缺失患者共29例,植入种植体共45枚。与种植体术前设计植入位置比较,种植体实际植入位置颈部的平均差距为(0.235±0.208)mm;尖端的平均差距(0.55±0.183) mm,深度的平均差距为(0.59±0.070) mm,角度平均差距为(2.48±0.378)°。其中,前牙的植入误差大于后牙。长度超过10 mm的种植体的位置偏差显著高于长度小于10 mm的植体。即刻种植与延期种植无显著差异。结论:牙支持式数字化外科导板引导下的种植具备良好的精准度,特别适合应用于即刻种植。同时在增加种植体的长度时应特别注意控制导板的精准度。     

种植体计算机辅助设计和制造导板精度的评价

目的利用三维重建软件设计并制作基于CT数据的计算机辅助设计和制造（CAD/CAM）导板,评价导板的精度。方法选择4个下颌骨标本,制作石膏模型,设计并制作基于CT数据的CAD/CAM导板。在导板辅助下于下颌骨标本的后牙段植入14枚种植体,再次行CT扫描,采用点对点配准技术实现扫描前后CT三维重建模型的配准,测量实际种植体位置与虚拟放置的种植体位置间的偏离值,评价导板的精度。结果14枚种植体植入后头部偏差量为（0.47±0.12）mm,颊舌向和近远中向以及垂直向偏离值分别为（0.22±0.08）mm、（0.25±0.06）mm、（0.30±0.11）mm。尾部偏差量为（0.19±0.07）mm,角度偏差量为1.79°±0.68°。结论在CAD/CAM导板辅助下于下颌骨模型植入种植体具有较高的精度,对于辅助临床种植体植入具有较高的价值。     

牙支持式半程导板在种植手术中的精度研究

目的:研究数字化牙支持式半程导板的安全性,探讨影响其精确性的因素。方法:选择50例2022年1～12月于上海市口腔医院修复科,行牙支持式半程手术导板辅助口腔种植术的患者,共种植成功65枚。使用3Shape软件测量和比对患者术后种植体的实际位点与术前设计的种植体虚拟位点的偏差,评估在使用牙支持式半程手术导板引导下的种植手术的精确度。结果:65枚种植体在轴向,颊舌向,近远中向的颈部偏差分别为(0.31±1.3)mm,(0.47±1.71)mm,(0.22±1.88)mm;根尖偏差：(0.35±1.82)mm,(0.45±2.33)mm,(0.09±2.33)mm;角度偏差：(5.7±4.01)°,(4.71±3.66)°;对照组(0.079 mm偏差值)与实验组种植体在三维方向上的种植偏差值无统计学意义(P>0.05)。单颗与多颗种植体颈部和根尖部在近远中向偏差<轴向偏差<颊舌向偏差,在颊舌向整体呈现颊向偏移,在近远中向略偏向近中。前牙种植体颈部偏差在三维方向上略小于后牙,但角度偏差略大于后牙,但前牙和后牙种植体的偏差无统计学意义(P>0.05)。结论:数字化牙支持...     

国产六维导板辅助无牙颌种植手术的精度分析

目的：评估国产六维数字化种植导板的精度,为临床应用提供减小偏差的方法和依据。方法：采用3D打印制作种植导板,应用于无牙颌患者,辅助外科植入,测量种植体术前设计和术后实际位置之间的偏差。选择16例无牙颌患者,测量172个植入位点。其中,10例患者上颌骨植入6颗植体,下颌骨植入4颗植体;6例患者上、下颌骨各均植入6颗植体;14例患者、28颗植体为倾斜植入。将术前锥形束CT（CBCT）数据导入国产六维齿科牙种植设计软件,设计和制作导板;应用数字化导板辅助植入手术;术后拍摄CBCT并导入六维软件进行三维重建,并与术前设计进行配准;将配准模型导出到Geomagic Studio软件进行分析,得出术前设计和植入后种植体的位置偏差,分析导板辅助下种植手术精度。采用SPSS 25.0软件包对样本进行配对t检验及单因素方差分析。结果：种植体顶部中心点距离偏差为（0.83±0.27） mm,水平向偏差为（0.60±0.21） mm;种植体底部中心点距离偏差为 （1.11±0.35） mm,垂直向偏差为（0.45±0.19） mm;角度偏差为（3.16±1.73）°。结论：六维数字化导板能够显著提高无牙颌患者种植手术精度和效率,并获得较好的远期临床效果。临床设计时须考虑偏差,规避风险和并发症。     

Accuracy of a chairside fused deposition modeling 3D-printed single-tooth surgical template for implant placement: An in vitro comparison with a light cured template

PurposeTo compare the accuracy of a chairside fused deposition modeling (FDM) 3D-printed surgical template with that of a light-cured template for implant placement.Materials and methodsTwenty standard mandibular resin models with missing teeth 36 and 46 were selected. Surgical templates were fabricated using a chairside FDM 3D-printer (test group) or a light-curing 3D printer (control group) (n = 20/group). Forty implants were placed by a clinician blinded to group allocation. The angular, 3D, mesiodistal, buccolingual, and apicocoronal deviations at the implant base and tip between preoperative design and postoperative implant position were recorded.ResultsThe mean angular (test vs control groups: 3.22° ± 1.55° vs 2.74° ± 1.24°, p = 0.343) and 3D deviations at the implant base (test vs control groups: 0.41 ± 0.13 mm vs 0.35 ± 0.11 mm, p = 0.127) and tip (test vs control groups: 0.91 ± 0.34 mm vs 0.75 ± 0.28 mm, p = 0.150) were similar. The mesiodistal, buccolingual, and apicocoronal deviations at the implant base and tip also did not differ significantly between groups (p > 0.05).ConclusionsFor single tooth gap indications, implant placement with an FDM 3D-printed surgical template was as accurate as that with a light-cured template, and more efficient.     

Influence of Metal Guide Sleeves on the Accuracy and Precision of Dental Implant Placement Using Guided Implant Surgery: An In Vitro Study

Purpose

Metal sleeves are commonly used in implant guides for guided surgery. Cost and sleeve specification limit the applications. This in vitro study examined the differences in the implant position deviations produced by a digitally designed surgical guide with no metal sleeve in comparison to a conventional one with a metal sleeve.

Materials and Methods

The experiment was conducted in two steps for each step: n = 20 casts total, 10 casts each group; Step 1 to examine one guide from each group with ten implant placements in a dental cast, and Step 2 to examine one guide to one cast. Implant placement was performed using a guided surgical protocol. Postoperative cone-beam computed tomography images were made and were superimposed onto the treatment-planning images. The implant horizontal and angulation deviations from the planned position were measured and analyzed using t-test and F-test (p = 0.05).

Results

For Step 1 and 2, respectively, implant deviations for the surgical guide with sleeve were –0.3 ±0.17 mm and 0.15 ±0.23 mm mesially, 0.60 ±1.69 mm, and –1.50 ±0.99 mm buccolingual at the apex, 0.20 ±0.47 mm and –0.60 ±0.27 mm buccolingual at the cervical, and 2.73° ±4.80° and –1.49° ±2.91° in the buccolingual angulation. For Step 1 and 2, respectively, the implant deviations for the surgical guide without sleeve were –0.17 ±0.14 mm and –0.06 ±0.07 mm mesially, 0.35 ±1.04 mm and –1.619 ±1.03 mm buccolingual at the apex, 0.10 ±0.27 mm and –0.62 ±0.27 mm buccolingual at the cervical, and 1.73° ±3.66° and –1.64° ±2.26° in the buccolingual angulation. No statistically significant differences were found in any group except for mesial deviation of the Step 2 group (F-test, p < 0.001).

Conclusions

A digitally designed surgical guide with no metal sleeve demonstrates similar accuracy but higher precision compared to a surgical guide with a metal sleeve. Metal sleeves may not be required for guided surgery.     

Fabrication of a cast-based implant surgical guide using guide sleeves

A unique method for fabricating cast-based surgical guides is presented. A proposed position and mesiodistal angulation of the implant are verified with periapical radiography and registered with a commercially available guide sleeve. The sleeve is attached to a surgical guide made of light-polymerized acrylic resin. The surgical guide can be used in a broad range of situations and allows for accurate implant placement in a prosthetically driven position with surgical access and visibility, simplicity, and cost efficiency.     

基于CAD/CAM技术的改良式金属牙种植导板的应用研究

目的 对Simplant牙种植导板进行改良设计,评价其临床应用效果。方法 利用Simplant软件设计种植导板,3Shape软件进行三维镂空改良设计,并铸造转化为改良金属导板。应用改良导板实施20例种植手术,植入31颗种植体,并评价种植体术后与术前三维设计的位置偏差：颈部偏移量、尖部偏移量与偏移角度,评估导板的固位、视野及散热性。结果 31颗种植体平均颈部、尖部偏移量分别为（1.5±1.1）mm和（2.1±0.8）mm,平均偏移角度（4±1.5）°,经t检验,差异无统计学意义（P>0.05）。改良导板临床应用固位稳定、视野清晰、散热良好。结论 改良式种植导板精度较高、利于散热、应用方便,具有辅助临床手术的价值。     

Accuracy of CAD-CAM Surgically Guided Tooth Autotransplantation Using Guided Templates and Custom-designed Osteotomes in Human Cadaver Mandibles

IntroductionA major challenge in dentistry is the replacement of teeth lost prematurely due to trauma, caries, or malformations; especially in growing patients. The aim of this study was to assess the accuracy of CAD-CAM surgically guided tooth autotransplantation in cryopreserved cadaver mandibles using guided templates and custom-designed osteotomes.MethodsCryopreserved human cadaver heads were digitized and scanned using an intraoral optical scanner and a large-volume cone beam computed tomography device. First, virtual surgical planning was performed to create a 3D tooth replica, 2 surgical guides, and a custom-made osteotome for each single-rooted tooth autotransplantation procedure/case. Surgical sockets were created in the selected mandibles using guided tooling consisting of an initial guided osteotomy with implant burs and a final guided osteotomy using custom osteotomes. After tooth autotransplantation, second large-volume cone beam computed tomography images of the 5 cadaver mandibles were obtained. The discrepancy in mm within the 3D space (apical and mesiodistal deviations) between the final position of the autotransplanted teeth and their digitally planned 3D initial position was calculated and analyzed statistically (P < .05).ResultsAll donor teeth were placed without incident within their newly created sockets in the real mandibles. The mean difference between the digitally planned root apex position and the final tooth position was 2.46 ± 1.25 mm. The mesiodistal deviation of the autotransplanted teeth was 1.63 ± 0.96 mm.ConclusionsThe autotransplantation of single-rooted teeth with custom-designed and 3D-printed surgical tooling provided promising results. The technique was able to create surgically prepared sockets that could accommodate transplanted teeth in mandibles.     

Stereoscopic Technique for Conversion of Radiographic Guide into Implant Surgical Guide

Purpose: The aim of this study was to develop and evaluate a new stereoscopic technique for conversion of radiographic guide into surgical guide for dental implant placement. Materials and Methods: Ten partially dentate patients requiring 18 implants for tooth replacement were recruited. Radiographic guides were modified with the addition of index rods for double computed tomography scanning. Implant positions were planned with implant planning software, and the stereoscopic angulations were measured. The radiographic guides were converted into surgical guides using either a generic bench drill (Group A, n = 9) or a milling machine (Group B, n = 9). Stereolithographic surgical guides were also made for three patients (Group S, n = 5). Differences between the planned and actual angulations were tested by pair‐sample t‐test. Difference of mean angle deviation among groups was tested by Brown–Forsythe test. Differences were considered significant if p < .05. Results: Eighteen implant sites were successfully treated with the converted surgical guides. The mean angle deviation of Group A (1.3 ± 0.6°) was significantly greater than Group S (0.4 ± 0.6°), while no differences were found between Group B (0.9 ± 0.3°) and Group S. The linear error was greatest in Group A with 1.5 mm at the head and 1.8 mm at the apex of the implant. Conclusions: The use of this new stereoscopic technique appears to be an acceptable alternative method for converting radiographic guide into surgical guide.     

计算机辅助设计和自制牙支持式导板用于下颌后牙区种植研究

目的 评价计算机辅助设计和自制牙支持式导板应用于下颌后牙区种植的临床疗效。方法 选择2012年4-9月山西医科大学口腔医院口腔外科收治的下颌后牙区单颗缺失患者10例,制取缺牙区牙列模型,选取植入点,制作初导板。采集CT数据,利用Simplant软件对数据分析,使用研磨仪在模型上确定最后植入方向并制作最终导板。口内戴入导板,植入种植体,拍摄CT,测量术前术后角度及深度偏差。结果 种植体在颊舌向与模拟植入体方向存在偏差,但偏差角度在10°以内,可以通过角度基台调整以适应咬合关系。种植深度及近远中向角度术前、术后偏差较小。结论 该系统可指导临床医生在下颌骨高度不足条件下植入种植体,对于提高种植手术质量与精度具有重要意义。     

Accuracy of implant position when placed using static computer-assisted implant surgical guides manufactured with two different optical scanning techniques: a randomized clinical trial

Data from cone beam computed tomography (CBCT) and optical scans (intraoral or model scanner) are required for computer-assisted implant surgery (CAIS). This study compared the accuracy of implant position when placed with CAIS guides produced by intraoral and extraoral (model) scanning. Forty-seven patients received 60 single implants by means of CAIS. Each implant was randomly assigned to either the intraoral group (n = 30) (Trios Scanner, 3Shape) or extraoral group (n = 30), in which stereolithographic surgical guides were manufactured after conventional impression and extraoral scanning of the stone model (D900L Lab Scanner, 3Shape). CBCT and surface scan data were imported into coDiagnostiX software for virtual implant position planning and surgical guide design. Postoperative CBCT scans were obtained. Software was used to compare the deviation between the planned and final positions. Average deviation for the intraoral vs. model scan groups was 2.42° ± 1.47° vs. 3.23° ± 2.09° for implant angle, 0.87 ± 0.49 mm vs. 1.01 ± 0.56 mm for implant platform, and 1.10 ± 0.53 mm vs. 1.38 ± 0.68 mm for implant apex; there was no statistically significant difference between the groups (P > 0.05). CAIS conducted with stereolithographic guides manufactured by means of intraoral or extraoral scans appears to result in equal accuracy of implant positioning.     

A dual-purpose guide for optimum placement of dental implants

Correct placement of implants is a requirement for implant treatment. The use of computed tomography and precise surgical guides is required when inadequate bone support is anticipated. This article describes the fabrication and use of an acrylic resin dual-purpose guide for radiographic evaluation of recipient sites and implant placement, which uses internally stacked stainless steel surgical guide channels. The drill guides are machined to allow consecutive surgical drills to be used without changing the implant angulation during surgery.     

Transfer accuracy of 3D-printed trays for indirect bonding of orthodontic brackets:: A clinical study

ObjectivesTo evaluate the transfer accuracy of 3D-printed indirect bonding trays constructed using a fully digital workflow in vivo.Materials and MethodsTwenty-three consecutive patients had their incisors, canines, and premolars bonded using fully digitally designed and 3D-printed transfer trays. Intraoral scans were taken to capture final bracket positioning on teeth after bonding. Digital models of postbonding scans were superimposed on those of corresponding virtual bracket setups, and bracket positioning differences were quantified. A total of 363 brackets were evaluated. One-tailed t-tests were used to determine whether bracket positioning differences were within the limit of 0.5 mm in mesiodistal, buccolingual, and occlusogingival dimensions, and within 2° for torque, tip, and rotation.ResultsMean bracket positioning differences were 0.10 mm, 0.10 mm, and 0.18 mm for mesiodistal, buccolingual, and occlusogingival measurements, respectively, with frequencies of bracket positioning within the 0.5-mm limit ranging from 96.4% to 100%. Mean differences were significantly within the acceptable limit for all linear dimensions. Mean differences were 2.55°, 2.01°, and 2.47° for torque, tip, and rotation, respectively, with frequencies within the 2°-limit ranging from 46.0% to 57.0%. Mean differences for all angular dimensions were outside the acceptable limit; however, this may have been due to limitations of scan data.ConclusionsIndirect bonding using 3D-printed trays transfers planned bracket position from the digital setup to the patient''s dentition with a high positional accuracy in mesiodistal, buccolingual, and occlusogingival dimensions. Questions remain regarding the transfer accuracy for torque, tip, and rotation.