上颌前牙倾斜角度对种植治疗设计的影响

目的 利用锥形束CT（CBCT）研究上颌前牙与牙槽骨的相对位置关系。方法 选取上颌恒牙牙列完整的患者150例（年龄19~48岁,男性和女性各75例）,按性别和牙位分为6个组。以牙槽骨长轴为基准,在CBCT影像上测量上颌前牙牙体长轴的相对倾斜角度（偏向腭侧为正,偏向唇侧为负）。使用SPSS 19.0软件对数据进行统计分析。结果 所有研究对象的上颌前牙的牙体长轴均偏向牙槽骨长轴的腭侧。男性上颌中切牙、侧切牙、尖牙的牙体长轴与牙槽骨长轴所成角度α的平均值分别为16.22°（2.50°~28.80°）、17.50°（3.80°~29.50°）、16.27°（1.00°~31.50°）,而女性的相应测量结果平均值分别为15.20°（2.20°~27.20°）、15.99°（4.10°~33.30°）、15.01°（3.50°~27.40°）。结论上颌前牙与牙槽骨的倾斜方向不一致,所有上颌前牙牙体长轴均偏向于牙槽骨长轴腭侧。通过CBCT观察上颌前牙与牙槽骨的位置关系,可以指导种植时机,种植体植入位置以及骨增量方案的选择。     

上颌中切牙间微种植体植入可靠性的CBCT测量研究

目的：通过锥形束CT（CBCT）测量分析，研究上颌中切牙间微种植体植入区的唇舌向牙槽骨量，探讨合适的植入高度与角度。材料与方法：选取80例年龄12~25岁正常人的CBCT影像资料进行三维重建，矢状面测量上颌中切牙间在距离参考平面14.0mm、16.0mm、18.0mm、20.0mm的四个植入高度上，分别以与骨皮质表面成60°、75°、90°的三个方向共12个植入路径的唇舌向骨质厚度。结果：微种植体不同植入部位唇舌向骨质厚度均大于7.0mm。相同高度水平，唇舌向骨量均为60°时最大，差异有统计学意义。大部分测量部位骨量男性大于女性。结论：上颌中切牙间可植入骨内长度为6mm的微种植体，微种植体与牙槽骨表面呈60°斜行植入可获得更多的骨量，高度的选择则建议按临床需要及患者的软组织状况而定。     

角度螺丝通道基台在上颌切牙种植修复的临床应用

目的:评估应用角度螺丝通道基台种植修复上颌切牙的临床效果。方法:临床选择2015年12月前使用角度螺丝通道基台行上颌切牙种植修复15例。随访6个月,观察方法为X线片、临床检查及患者满意度调查,分析其存留率、骨吸收情况、软组织及美学效果。结果:使用角度螺丝通道基台的上颌切牙种植义齿存留率为100%;种植体近远中牙槽骨吸收量为(0.447±0.121)、(0.355±0.127) mm,软组织状况良好; 93.3%患者对种植修复表示满意。结论:使用角度螺丝通道基台行上颌切牙种植修复是一种微创、简洁的种植治疗方案设计,有一定的临床推广价值。     

前牙美学区种植ASC螺丝固位修复的三维有限元分析

目的 通过有限元软件研究ASC角度螺丝通道螺丝固位修复种植牙在负载时各部位应力峰值及分布情况.方法 通过软件建立三组不同植入角度以及螺丝通道角度的模型.使用有限元软件对三组模型加载,对比模型各配件的应力峰值及分布情况.结果 使用25°螺丝通道的B组与直通道的A组比较,牙槽骨、适配器底座及牙冠应力峰值大,而修复螺丝和种植...     

微种植体颌骨植入区的CBCT测量分析

目的 利用锥体束CT（cone beam computed tomography,CBCT）分析上颌第二前磨牙与第一磨牙以及下颌第二磨牙近中颊根侧植入的微种植体周围组织结构。方法 收集34名患者的CBCT数据。上颌测量不同植入角度的颧牙槽嵴厚度及种植体与上颌平面间的距离;下颌测量不同植入高度牙槽骨各部位的最小植入角度以及颊侧骨厚度。结果 ①上颌距离平面13～17 mm植入微种植体,植入角度为40°～75°,上颌颧牙槽嵴厚度为（4.7±0.3）mm～（8.1±0.1）mm。②在下颌不同的植入点中,距离平面11 mm时植入角度应大于82°,距离平面16 mm时,植入角度应大于51°;距离平面11 mm第二磨牙颊侧牙槽骨厚度最小,距离平面16 mm时最大。③不同植入点中,以距离平面16 mm植入时至下颌神经管上缘的平均距离最小,为（9.0±1.6）mm。结纶 ①为保证上颌颧牙槽嵴骨厚度至少6 mm且不触及上颌窦底壁,理想的植入位置为距离上颌平面13～16 mm,植入角度55°～75°。②在第二磨牙近中根颊侧植入微种植体时,建议植入点与平面距离大于12 mm,植入最小角度依不同植入点而异     

螺丝固位个性化烤瓷基台结合Ⅲ型瓷贴面修复单颗缺失牙

一名24岁白人男性患者两年多前右下颌侧切牙因车祸致脱位，复位处理失败后拔除，邻近的中切牙因牙髓坏死行根管治疗术。检查：缺牙区颊舌侧牙槽骨凹陷，缺牙间隙减小。为解决本病例修复间隙小、固位螺丝通道与切缘成角度和种植体龈下肩台等美学修复难题，特采用螺丝固位的个别制作的金一瓷基台一金瓷贴面粘接技术等方法修复缺失牙。     

上切牙区双端悬臂梁种植固定桥的应力分析

目的：通过分析双端悬臂梁种植义齿修复上颌切牙区牙列缺损的种植体在不同加载条件下的周围骨应力分布及位移量,进而探讨临床修复的可行性。方法：应用CT断层扫描技术对上颌骨及上颌牙列的大致轮廓进行三维重建,后于上中切牙区植入种植体,完成牙冠修复并建立模型。通过三维有限元技术模拟载荷,比较不同加载条件下种植体的周围骨组织应力分布及位移量。结果：经统计学分析,种植体-骨界面的皮质骨唇侧、舌侧、近中、远中、根尖部五个部位应力值的差异有统计学意义（P〈0.001）,五个部位的位移量的差异也有统计学意义（P〈0.001）。模型在各种加载条件下的应力分布及位移量的特征大致相同,且变化趋势相似,种植体颈部及周围骨皮质为应力集中区。在各种不同的加载条件中,30°加载角度时种植体周围骨应力分布更为科学。结论：在适当的负重条件下,双端悬臂梁种植义齿是临床修复切牙区缺失可供选择的一种设计方案。     

植入位点及轴向对不同牙槽窝形态上中切牙即刻种植即刻负重应力影响的三维有限元分析

目的 基于三维有限元法,分析并探讨不同牙槽窝形态下,上颌中切行牙即刻种植即刻负重时,植入位点及轴向对种植体、基台、中央螺丝、牙冠应力分布的影响。方法 参照1名健康成年人的口腔CBCT影像资料;建立偏唇型、中间型、偏腭型三种牙槽窝形态的上颌中切牙即刻种植即刻负重的三维有限元模型;模拟不同植入位点(根尖位点、偏腭/唇侧位点)及轴向(牙长轴、牙槽骨长轴);对已建立的模型以100 N的力进行应力加载;应用ANSYS软件分析种植体、基台、中央螺丝、牙冠的应力值。结果 成功建立12个不同牙槽窝形态的上颌中切牙即刻种植即刻负重三维有限元模型;牙槽窝偏唇型及偏腭型的上颌中切牙行即刻种植即刻负重时,沿牙槽骨长轴偏腭/唇位点进行植入,种植体及其上部结构所受应力最小;中央型上颌中切牙行即刻种植即刻负重时,沿牙长轴偏腭位点进行植入,种植体及其上部结构所受应力最小。结论 不同牙槽窝形态、植入位点及轴向,都会对上颌中切牙即刻种植即刻负重种植体及其上部结构生物力学特点产生影响。医生应针对不同牙槽窝形态制定不同植入轴向及植入位点的手术方案。     

中国人上颌前牙区骨质形态的CBCT测量分析

目的:通过锥形术射线计算机控制断层扫描(cone beam computed tomography,CBCT)测量分析,研究中国人上颌前牙区的骨质形态,了解上颌前牙区种植修复相关参数。为中国人上颌前牙区种植修复提供相应的参考。方法:选取112例浙江大学医学院附属口腔医学院就诊的中国人患者的CBCT资料,测量上颌前牙区各受测牙在釉牙骨质界处的唇侧骨壁的厚度,牙冠与牙根长轴的角度以及若采取理想种植方案,种植体根方的骨质情况。结果:中切牙、侧切牙和尖牙在釉牙骨质界处的唇侧骨壁厚度不足1.0 mm的比率均超过50%,牙冠与牙根长轴均有一定的角度,若采用理想修复效果指导种植,种植体根方骨质不足。结论:中国人群上颌前牙区多为凸面型,较难获得与修复牙冠方向及位点均合适的种植骨支持。在上颌前牙区种植患者中建议使用CBCT等技术手段进行的术前评估,对于不能获得与修复牙冠方向及位点均合适的骨支持的病例可以通过角度基台修复或引导骨组织再生等技术获得理想的功能及美学效果。     

中重度慢性牙周炎上颌中切牙区解剖形态的锥形束CT测量分析

目的应用锥形束CT（CBCT）测量分析中重度慢性牙周上颌中切牙区牙槽骨的骨量和牙齿偏移度,为上颌中切牙区的种植治疗和方案制定提供解剖学依据。 方法选取2015年1月至2017年12月深圳爱康健口腔医院内150例中重度牙周炎患者的CBCT影像资料,测量共290颗上颌中切牙唇/腭侧骨壁厚度、牙槽骨骨宽/高度、骨内根长、牙体长轴和牙槽骨走行方向的夹角共7个项目,采用SPSS 19.0统计软件包对测量结果进行相关统计分析。 结果中重度慢性牙周炎上颌中切牙牙槽嵴顶处和根尖处的唇腭向骨厚度分别为（7.68 ± 0.78）mm和（8.52 ± 1.55）mm,牙槽骨高度平均为（18.35 ± 3.45）mm,骨内根长1/2处的唇侧和腭侧的骨壁厚度分别为（0.62 ± 0.45）mm和（3.18 ± 1.00）mm,牙体长轴与牙槽骨走行方向夹角的平均值为18.80° ± 5.46°。不同性别间对比测量结果,在牙槽嵴顶骨宽度和根尖区骨宽度处差异均有统计学意义（P<0.05）,男性优于女性。 结论中重度慢性牙周炎上颌中切牙的唇侧骨壁菲薄甚至缺如,骨量条件不理想,牙体长轴与牙槽骨偏移度明显,在制定种植方案时有必要充分利用CBCT了解骨量情况并评估解剖形态,为达到上颌中切牙种植效果长期美观、稳定的需求应有更多的考量。     

Frequency of screw-retained angulated screw channel single crown following immediate implant placement and provisionalization in the esthetic zone: A cone beam computed tomography study

Objective

The purpose of this cone beam computed tomography (CBCT) study was to determine the frequency percentage of screw-retained crown using angulated screw channel (ASC) abutment for single immediate implant placement and provisionalization (IIPP) in the esthetic zone.

Methods

The CBCT images of 200 patients without disease and without metal restorations in maxillary anterior teeth were evaluated. The mid-sagittal-sectional CBCT images of maxillary anterior teeth (#6–#11) were created in an implant planning software, screen-captured, and transferred to a presentation program. Template of tapered implants with diameter of 3.5 mm (for central and lateral incisors) and 4.3 mm (for central incisors and canines) and lengths of 13, 15, and 18 mm were applied to the sagittal images to identify the IIPP cases. To qualify for IIPP, the implant must engage >35% bone with at least 1 mm of surrounding bone and no perforations. The IIPP cases were further divided into straight screw channel (IIPPSSC) abutment or 25-degree angulated screw channel abutment (IIPPASC), based upon its restorability. The frequency percentages of possible IIPP, IIPPSSC, and IIPPASC were reported and compared among all maxillary anterior teeth.

Results

A total of 1200 maxillary anterior teeth sagittal images from 200 patients (88 male and 112 female) with a mean age of 51.3 years (range 20–83 years) were evaluated in this study. The overall frequency percentages of IIPP, IIPPSSC, and IIPPASC possibility were 84% (74%–92%), 14% (10%–24%), and 75% (66%–87%), respectively.

Conclusion

Within the limitations of this CBCT study, 90% of single IIPP in the esthetic zone can be restored with screw-retained crown when utilizing ASC. In addition, the possibility of using a screw-retained restoration following IIPP increases about five times with ASC abutment compared to the SSC abutment.     

An esthetic solution to the screw-retained implant restoration: introduction to the implant crown adhesive plug: clinical report

Screw-retained implant crowns may be clinically demanding, especially managing the esthetic and occlusal challenges of screw access channel closure. Many clinicians have moved away from using screw retention as a means of fixing a crown to an implant in favor of cementation to an underlying abutment. A link has been established between peri-implant disease and excess cement extrusion in cement-retained implant restorations. This article describes a novel technique of bonding a pressed porcelain plug into the screw access channel of an implant restoration that allows for control of occlusion, matches the esthetics of a cement-retained crown, and eliminates the issues of excess cement. CLINICAL SIGNIFICANCE: Overcoming the restorative challenges (esthetic, occlusal) of the screw access channel in a screw-retained implant restoration is difficult. By fabricating a pressed ceramic over metal crown and esthetic plug these challenges can be dealt with in a predictable manner.     

Management of a prosthetic complication on an implant restoration placed when the patient was 10 years old: A case report

The use of dental implants in pediatric patients may create unique complications. A 38-year-old patient presented with a mobile, cement-retained implant crown due to an abutment screw loosening. The maxillary right central incisor implant was placed when the patient was 10 years old. Pus discharge from the peri-implant sulcus was observed. The mucosal margin of the implant was at the level of the mucogingival junction of neighboring teeth. Radiographically, the platform of the implant appeared to be at the level of the apical third of the adjacent roots. After removing the existing implant-retained crown, the inflamed peri-implant tissue covering the implant platform was removed and the stability of the implant was confirmed. A new screw-retained implant crown was made using an angulated screw channel to correct the labiopalatal angulation of the implant and allow for retrievability. Pink porcelain was used to match the mucosal margin of the implant crown to that of the maxillary left central incisor. This case report highlights the risk of implant placement in pediatric patients and agrees with previous reports that implants should be delayed until growth is complete.     

Esthetic abutment design for angulated screw channels: A technical report

Angulated screw channel system abutments (ASCs) have recently been introduced to address the problem with visible screw access that may compromise esthetics. ASCs allow the screw access to be modified up to 25 degrees relative to the implant axis. However, a widened channel, which may cause thinning of the facial ceramic, is needed at the implant screw head to allow for proper engagement of the screwdriver. This technical report introduces a custom titanium insert design, the Satoshi Sakamoto (SS) abutment. The SS abutment consists of a custom titanium metal insert and zirconia coping in which the access hole is located in an esthetic position with an ASC system. The SS abutment results in a crown with more normal crown dimensions that also provides more space for the soft tissues. This SS abutment design allows clinicians to obtain screw-retained restorations with optimal esthetics and mechanical strength.     

不同牙本质肩领高度的上颌中切牙用不同材料桩核冠修复的有限元分析

目的 应用三维有限元法分析具有不同牙本质肩领高度的上颌中切牙,在选用不同材料桩核冠修复后的应力分布。方法 通过螺旋CT扫描、Mimics和Geomagics等软件建立桩核冠修复的上颌中切牙有限元模型,模拟玻璃纤维、氧化铝陶瓷两种材料在0 mm、1 mm、2 mm、3 mm 4种牙本质肩领高度,在上颌中切牙舌侧切1/3与中1/3交界处,与牙体长轴成45°切龈向加载,载荷量为100 N,加载方式为静态加载,分析牙本质内的Von Mises应力和位移。结果 纤维桩和陶瓷桩对上颌中切牙修复后的应力集中区均位于桩尖牙本质中,随着材料弹性模量的升高应力峰值明显增加,陶瓷桩修复的上颌中切牙应力峰值（11.263 0 MPa）明显高于纤维桩修复的应力峰值（9.745 9 MPa）。陶瓷桩材料修复上颌中切牙的Von Mises应力值和位移受牙本质肩领高度的影响较小,随着牙本质肩领高度的降低,Von Mises应力值逐渐下降,最大主应力和最小主应力均逐渐增加,修复后的位移也随牙本质肩领高度的降低而下降。结论 通过建立不同牙本质肩领高度上颌中切牙的桩核冠修复的有限元模型和应力分析,能够预测不同材料对不同牙本质肩领高度的上颌中切牙应力分布的影响,应根据不同牙本质肩领高度选择不同的桩核材料。此外,适当保留牙本质肩领结构对提高修复效果具有重要意义。     

Immediate maxillary lateral incisor implants with nonocclusal loading provisional crowns.

This clinical report series describes a treatment modality involving immediately placed dental implants in maxillary lateral incisor sites using noncemented immediate provisional crowns retained with calcinable copings (prosthetic complement used in preparing the metal for the definitive prosthesis). Ten implants were placed in eight patients for the replacement of maxillary lateral incisors: two immediate and eight corresponding to cases of agenesis. All were subjected to immediate rehabilitation with provisional acrylic resin crowns in nonocclusal loading. One implant failed 3 weeks after placement due to acute local trauma. The other nine remained functional within the mouth, with normal clinical and radiological characteristics after a minimum of 12-month follow-up. Immediate placement of implant fixed provisional restorations retained by friction in maxillary lateral incisors offers an esthetic solution, eliminates the need for a removable provisional restoration, and avoids implant failures associated with excess cement or screw loosening. Moreover, in the case of extractions, immediate placement and provisionalization of implants in maxillary lateral incisors can effectively optimize the peri-implant esthetic results by maintaining the existing hard and soft tissue architecture of the replaced tooth. As no cement or screws are required, and the provisional crowns are placed in nonocclusal loading, the risk of complications is minimized.     

后牙种植义齿一体化冠修复及软组织整复效果的评价

目的:局部种植义齿冠修复方式可分为粘接固位修复和螺栓固位修复两种。粘接固位较螺栓固位在受力,美观和被动就位上有较大的优越性,但对于冠破损需要修改时,螺栓固位有着粘接固位所不及的优势,同时也避免了粘结剂的遗留对牙龈健康的影响。常规的螺栓固位方式,是先将固位基台与种植体连接后,用螺丝将冠固定在基台上,由于固位力小易出现松动,但对于后牙颌间距离低且咬合紧或植体植入位置不佳时,效果并不理想。而且,后牙种植义齿冠修复容易出现牙龈乳头无法良好塑形充满楔状隙,从而影响美观并容易引起水平性食物嵌塞。基台冠一体化修复的方式是基台与冠为一整体通过牙合面开孔螺栓固位方式进行修复。本研究评价后牙种植体冠修复方式中选择行一体化冠修复并观察其对软组织同期整复的临床效果。材料与方法:使用两种方法进行一体化冠修复:一为基台与冠整体铸造后牙合面开孔螺栓固位修复;二为采取冠分体铸造后预留冠牙合面螺丝孔,将基台与冠粘结成一体,取下基台一体化冠于口外去除多余粘结剂后放置口内再通过螺栓固位。对软组织整复也分两种,一种为先用暂冠逐步整复软组织后行冠修复;二为在试戴一体化冠时同时将其作为对软组织进行整复的方式,并评价两种操作对软组织整复的效果。冠修复材料选用金属烤瓷或聚合瓷。29例患者植入种植体共48枚,其中14例患者应用ITI种植体系统植入19枚植体,15例患者使用OsstemGS种植体系统植入植体29枚。上部结构修复均使用基台一体化冠修复方式,ITI系统均为单冠修复,OsstemGS系统采用单冠或联冠修复。其中ITI系统2例患者2枚植体,OsstemGS系统3例患者3枚植体进行种植植入术后使用种植体临时义齿通过数次复诊,逐步整复软组织后依整复后的软组织外形取模,一体化冠修复。余病例均采用一体化冠修复戴用时同期对软组织整复。修复过程中均拍摄X-RAY片检查基台是否完全就位。完成修复后随访6个月-1年,复诊时行X-RAY检查并评估种植体一体化冠的松动度和软组织整复效果及健康。结果:种植体冠使用期间未出现松动脱落现象,种植体也未出现松动及暴露;直接行基台冠一体化修复方式对龈缘位置及龈乳头高度均有较好的塑形效果,游离龈位置佳且龈乳头高度丰满充满楔状隙。未观察到种植义齿后牙冠修复长期以来的水平性食物嵌塞问题;无论戴用一体化冠同期观察软组织整复情况或临时义齿整复牙龈后再行一体化冠修复,均可达到较好的软组织塑形及整复效果,无龈炎、龈乳头退缩导致食物嵌塞;其中一例患者在种植体植入位置不佳偏向远中时通过一体化冠修复方式获得了满意的修复效果。牙合面开孔螺丝影响美观问题也通过聚合瓷修复得到了很好的解决。结论:1)后牙种植义齿冠修复时采用一体化冠修复方式对软组织能达到较好的的整复效果,解决种植义齿后牙冠修复长期以来的水平性食物嵌塞问题;2)在植体位置不佳时及咬合过紧时也能获得较好的修复效果;3)基台一体化冠修复同期对软组织整复,操作简单,避免了先期软组织整复过程中多次复诊调改,节约了患者的时间和费用;4)基台一体化冠减少了龈炎、水平性食物嵌塞的发生,有利于软组织健康和冠的维护,不失为种植义齿后牙冠修复时选择的一种好方法。     

Selecting treatment options and sequencing treatment in the replacement of 2 maxillary central incisors with implants: a case report

This article describes treatment provided to replace 2 maxillary central incisors with implant-supported restorations. The site of a missing maxillary central incisor was treated utilizing a bone expansion technique to augment the labial hard and soft-tissue profiles at the time of implant placement. The adjacent central incisor tooth, although destined to be extracted, was retained to serve as an abutment for a fixed provisional restoration until the first implant was deemed to have successfully integrated. At the appointment to uncover this implant, the fractured tooth was extracted and an implant was immediately placed into the socket. The first implant was then used to support the provisional restoration during the healing phase of the second implant. The techniques utilized resulted in optimum soft-tissue contours, allowed the patient to have a comfortable and esthetic provisional restoration, and minimized the number of surgical procedures.     

Fabrication of a cement- and screw-retained multiunit implant restoration

Retrieval of cemented implant restorations can be difficult for both the patient and the dentist. The method described in this article combines the advantages of cement- and screw-retained restorations. Abutment screws can be easily reached by the screw access channel prepared in the waxing phase; the restoration can be retrieved without destroying the implants and prosthesis. This article describes a simple and reliable method to fabricate a retrievable cemented prosthesis.