螺旋CT测量上颌窦体积在种植牙中的应用分析

目的：通过螺旋CT扫描,对正常人的上颌窦进行三维重建,得出体积测量的方法,为种植牙术提供解剖依据和手术指导。方法：选取57例（114侧）健康成人的付鼻窦CT影象,对上颌窦进行螺旋CT连续容积扫描,三维重建,在选取的截面测量上颌窦的有关数据,估算上颌窦的体积变化,并对所测的数据进行统计分析。结果：上颌窦的平均容积为13.83±5.70mm^3,男性和女性、左侧和右侧、以及缺牙组和无缺牙组均无显著性差异（P〉0.05）。结论：螺旋CT可以估算上颌窦的体积,所得数据对种植牙,特别是上颌窦提升术有指导意义。     

CT三维重建上颌窦底壁形态研究和在种植牙中应用分析

目的：通过螺旋CT扫描,对正常人的上颌窦进行三维重建和测量,以建立有关上颌窦底壁解剖规律的一些参考数据,为种植牙手术方案的制定提供依据。方法：选取127例（254侧）健康成人的付鼻窦CT影象,对上颌窦进行螺旋CT连续容积扫描,三维重建,在选取的截面测量上颌窦的有关数据,并对所测的数据进行统计分析。结果：上颌窦底壁的形态以平坦型多见,上颌窦底壁的最底点位于上颌第二前磨牙和第一磨牙间多见,以偏腭侧为主（P〈0.01）,距牙槽嵴的平均距离为12.4±2.4mm。结论：螺旋CT可以提示上颌窦底壁的解剖特征,测量有关数据对种植牙有重要意义。     

基于三维重建对牙种植骨移植材料的定量研究

目的 探讨基于Simplant软件三维重建对牙种植患者骨移植材料的定量评估.方法 对9例牙种植修复Ⅰ期手术同期完成引导骨再生术的患者,在术后1周、3个月、6个月分别进行种植区螺旋CT扫描,对螺旋CT图像进行三维重建和数据分析,通过测量计算骨移植材料Bio-Oss在植入人体后不同时期的体积,以术后1周剩余体积为基线体积,计算其在术后3个月、6个月的剩余量,剩余量=复诊时剩余体积/基线体积×100％.结果 通过测量、计算,得出Bio-Oss在术后3个月的剩余量为（52.49 ±7.03）％,术后6个月的剩余量为（30.00±8.35）％.结论 三维重建评估发现牙种植修复引导骨再生术中所植入的骨移植材料Bio-Oss随时间延长有明显的吸收.     

牙槽突裂植骨吸收率的测量分析

目的:应用螺旋CT三维重建比较牙槽突裂植骨术后不同时间骨量的变化及吸收率。方法:选取单侧完全性牙槽突裂患者,应用螺旋CT三维重建患者术前牙槽突裂隙,利用GE AW4.1软件感兴趣区(ROI)体积测量法对其术后1周、3个月、6个月的牙槽部植骨进行体积测量,获得体积变化数据。结果:术后3个月,植入骨量丧失35.74%;术后6个月,植入骨量丧失55.89%,且在牙槽部颊侧形成良好骨桥的前提下,植入骨在空间上仍有不同程度的吸收,在腭侧较少有骨桥形成。结论:牙槽突裂植入骨存在一定吸收,而且随着时间推移,骨量吸收相应增加。     

螺旋 CT 仿真内镜对上颌窦底的测量研究

目的:探讨螺旋CT仿真内镜(virtual endoscopy VE)对评估上颌窦内提升前后窦底形态改变的意义。方法:对15例上颌窦内提升患者术前术后采用64排螺旋CT扫描,三维重建后仿真内镜观察上颌窦底形态改变,测量内提升高度及窦底种植体表面覆盖的软硬组织的厚度。结果:15例上颌后牙缺失患者经过螺旋CT仿真内窥镜术前测量,可以清晰地看到上颌窦内呈现不规则锥形结构,影像类似于真实内镜的图像。上颌窦底形态平坦型:9例(60.0%),V形:4例(26.7%),窦底分隔:2例(13.3%),上颌窦底最低点位置:上颌第二前磨牙与上颌第一磨牙间,种植有效牙槽骨高度:5-8mm,平均6.5mm。模拟手术评估后共植入21枚种植体。术后螺旋CT仿真内镜可以清晰地看到上颌窦底内提升后局部隆起的"帐篷状"改变,21枚种植体提升上颌窦底3±1.5mm,窦底种植体表面覆盖的软硬组织的厚度2.5±0.8mm。结论:螺旋CT仿真内镜是一种无创性、可重复操作的检查手段,不仅可以对骨组织进行三维重建,还可以对软组织进行重建,能多角度、全方位地清晰显示上颌窦内提升前后窦底形态结构的改变,对基层综合性医院上颌窦内提升有着重要的临床价值。     

经牙槽嵴顶行上颌窦底提升同期植入种植体的疗效评价

目的:观察使用骨挤压器经牙槽嵴顶入路提升上颌窦底、同期植入种植体的临床效果。方法:对104例单侧或双侧上颌后牙缺失患者,经牙槽嵴顶入路行上颌窦底提升,同期植入种植体,共126颗。全部病例均行X线曲面断层片,其中30例在后期随访中行螺旋CT扫描及三维重建。结果:上颌窦剩余牙槽骨平均高度为9.16mm(5～11mm),用骨挤压器平均提升上颌窦底高度3.95mm(2～6mm),无1例上颌窦黏膜穿孔。随访16～82个月,成功率达100%,所有病例均无上颌窦并发症。CT扫描及三维重建显示,种植体顶端有一层完整骨质覆盖,种植体完全埋入骨质中。结论:应用骨挤压器,经牙槽嵴顶入路行上颌窦提升同期植入种植体,与上颌窦外提升术相比,手术创伤小、操作简便、并发症少,其近、远期效果均满意;螺旋CT扫描及三维重建可作为上颌窦提升种植体植入术后判断手术效果的有效手段。     

多排螺旋CT三维成像技术在种植牙上颌窦内提升中的应用

目的 探讨三维螺旋CT在评估上颌后牙区牙槽骨高度及指导上颌窦内提升术中的作用。方法 21例病例拍摄全景片测量牙槽嵴高度后,再拍摄三维螺旋CT测量各部位牙槽骨高度、明确上颌窦底形态。所有病例均采用上颌窦内提升术同期植入种植体。结果 全景片及CT测量得出的植区最低高度分别为（0.85±0.11） cm和（0.70±0.10） cm（P＜0.05）,有统计学差异;经CT诊断平坦、斜坡、“w”型窦底形态分别为3、12、6例。术后均未发生并发症,随访观察12~30个月,短期疗效满意。结论 三维螺旋CT可精确测量上颌骨各部位的骨高度,可明显提高种植前对颌骨质量评估的准确率。     

上颌后牙区数字化导板引导下倾斜种植精确性研究

目的 评估上颌后牙区使用数字化外科导板引导进行倾斜种植的精确性.方法 上颌后牙缺失伴垂直骨量不足病例14例,术前拍摄锥形束CT(cone beam computed tomography,CBCT)获得颌骨数据,扫描上颌石膏模型获得上颌数字化模型,将数据输入种植设计软件后完成导板的设计,再通过快速成型技术完成导板的制作.在导板的引导下完成手术,术后拍摄CBCT,将CBCT数据导入种植设计软件,与术前种植设计数据进行匹配整合后测量种植体设计位置与实际位置的差异.结果 纳入研究的14例患者在数字化外科手术导板引导下共植入26枚种植体.种植体计划植入位置尖端与种植体实际植入位置尖端的平均距离是(0.820±0.208)mm,两尖端水平向平均距离是(0.509±0.139)mm,垂直向平均距离是(0.638±0.178)mm.种植体计划植入位置的顶端与种植体实际植入位置顶端的平均距离是(0.625±0.183)mm,两顶端水平向平均距离是(0.314±0.070)mm,垂直向平均距离是(0.538±0.178)mm.结论 上颌后牙区倾斜种植技术能降低手术风险及创伤,使用数字化外科导板能降低手术难度、减少手术时间,但该技术仍存在一定误差.     

种植区牙槽骨密度的螺旋CT测量研究

目的：探讨螺旋CT对种植区牙槽骨密度测量的意义。方法：通过对30例上下颌种植区牙槽骨的螺旋CT扫描,在计算机工作站上三维重建、模拟种植,分别测量模拟种植体颈部、中部和根尖部牙槽骨的HU（hounsfield Unites）值,同时测量模拟种植体周围起支持作用的环状区域牙槽骨的HU值,并根据Lekholm和Zarb的分类法确定相对应区域的牙槽骨骨密度分类。结果：所有模拟种植体周围环状区域牙槽骨的平均骨密度为789±235HU,高于模拟种植体区牙槽骨的平均骨密度695±216HU（P〈0.01）,其中,下前牙环状区域牙槽骨平均骨密度最大,为1004±150HU,下颌后牙区为874±241HU,上颌前牙区为821±207HU,上颌后牙区为503±193HU。结论：螺旋CT扫描三维重建,测量模拟种植体周围起支持作用的环状区域牙槽骨密度,对种植前的评估和设计有着重要的指导意义。     

Sinustech上颌窦底开孔钻在种植中的应用

目的：观察上颌窦底开孔钻在种植上颌窦提升手术的临床应用效果。方法：9例种植修复上颌后牙缺失需要上颌窦提升手术患者,男7例,女2例,平均年龄51.6岁,平均牙槽骨高度7.8mm。通过CT扫描三维重建分析、模型手术分析精确测量种植区域牙槽嵴顶到上颌窦底的距离,计算出种植体与上颌窦底的接触位置,测量种植体这一位置的直径,再通过骨质分类预定好上颌窦底开孔直径,制作种植手术导板进行种植导航手术,先用先锋钻钻至距上颌窦底1mm深度,然后换上选定直径的上颌窦底开孔钻,逐级扩大种植窝洞同时收集开孔钻槽沟上的自体骨屑,最后将种植窝洞预备到术前设计的直径并将上颌窦底皮质骨钻开一定直径大小的圆孔,提升上颌窦粘膜后植入收集到的自体骨或/和人工骨后安放种植体,检查初期稳定性。术后即刻CT检查植入方向、植骨情况、粘膜穿孔情况。结果：上颌窦底开孔后粘膜完整,种植体初期稳定性好;CT检查种植体与骨组织接触紧密,种植体尖端为骨粉和粘膜覆盖包绕,粘膜完整连续无破溃。结论：通过螺旋CT三维重建分析和快速成型模型手术来获得牙槽嵴顶到上颌窦底的精确距离对于用上颌窦底开孔钻在上颌窦底钻出特定直径的孔至关重要,没有骨折的上颌窦底骨质能增强种植体初期稳定性,术中取出自体骨屑可以减少人工骨粉的使用,提升术中粘膜完整无穿孔,方法简便安全,值得推广。     

侧壁开窗上颌窦底提升术后垂直向骨增量的观察研究

目的通过观察侧壁开窗上颌窦底提升术后垂直向骨增量的变化情况,研究其相关的影响因素。方法收集上颌后牙区牙列缺损行侧壁开窗上颌窦底提升术分期种植患者资料,对纳入病例的术前剩余牙槽骨高度(residual bone height,RBH)、术后当日垂直向骨高度、术后6个月垂直向骨高度及垂直向骨增量的变化情况进行观察。结果术后6个月较术后当日垂直向骨高度有显著性降低,降低量为0.56±0.25mm;上颌窦底黏膜厚度的术后6个月较术后当日垂直向骨增量的变化量无明显差异;在不同剩余牙槽骨高度情况下,术后6个月较术后当日垂直向骨增量的变化量有统计学差异,RBH大于5mm的患者相对RBH小于5mm的患者垂直向骨增量的降低值显著增加;上颌窦宽度与术后6个月较术后当日垂直向骨增量的降低值呈正相关。结论侧壁开窗上颌窦底提升术后6个月较术后当日存在垂直向骨增量的降低现象;剩余牙槽骨高度大于5mm时垂直向骨增量的降低值显著增加;上颌窦宽度与垂直向骨增量的降低值呈正相关。     

Radiographic outcome after maxillary sinus floor augmentation with allogeneic adipose tissue-derived stem cells seeded on deproteinized bovine bone mineral. A randomized controlled experimental study

The objective was to test the hypothesis of no difference in radiographic outcome after maxillary sinus floor augmentation (MSFA) with allogeneic adipose tissue-derived stem cells (ASCs) seeded on deproteinized bovine bone mineral (DBBM) (test) compared with excipient on DBBM (control). Eighteen minipigs were assigned into three groups of six animals and euthanised after one month (T1), two months (T2), and four months (T3), respectively. Each maxillary sinus was randomly allocated to either test or control with an equal volume of graft. Computed tomography scans (CTs) after MSFA (T0) were compared with CTs after euthanasia to evaluate graft volume (GV) changes and bone density (BD) using three-dimensional measurements and Hounsfield units. GV was larger in test compared with control at T1 (P = 0.046), whereas GV was larger in control compared with test at T3 (P = 0.01). BD increased from T0 to T1-T3 (P < 0.001) with both treatments. Higher BD was observed in control compared with test at T3 (P = 0.01), while no significant difference was observed at T1 and T2. Conclusively, the present study demonstrate that allogeneic ASCs seeded on DBBM in conjunction with MSFA seemed not to improve the radiographic outcome compared with excipient on DBBM. However, radiological outcomes need to be supplemented by bone histomorphometry before definitive conclusions can be provided about the beneficial use of allogeneic ASCs seeded on DBBM in conjunction with MSFA compared with DBBM alone.     

Maxillary sinus floor elevation and grafting with deproteinized bovine bone mineral: a clinical and histomorphometric study

Objectives: This study evaluated the histomorphometric and clinical outcomes of maxillary sinus floor elevation using deproteinized bovine bone mineral (DBBM). Material and methods: Maxillary sinuses with a residual vertical height of <5 mm were augmented with DBBM alone before implant placement 9 months later. At the time of implant surgery, trephine samples were removed and histological and histomorphometric analyses were performed to examine the percentage of bone and residual graft using point counting and software‐aided analysis. Patients were recalled for clinical and radiographic examination up to 3 years later. Results: Twenty‐five patient specimens were analysed. The percentages of regenerated bone and residual graft material were 19% and 40%, respectively. Software‐aided analysis was comparable to point counting. Twelve patients attended for clinical follow‐up. Implants placed into this regenerated bone exhibited success and survival rates of 100% after an average follow‐up of 3 years. The average vertical height gained was 7.9 mm. Conclusions: The use of DBBM alone in maxillary sinus floor elevation is a predictable method to gain vertical bone height in the posterior maxilla. To cite this article :
Lee DZ, Chen ST, Darby IB. Maxillary sinus floor elevation and grafting with deproteinized bovine bone mineral: a clinical and histomorphometric study.
Clin. Oral Impl. Res. 23 , 2012; 918–924
doi: 10.1111/j.1600‐0501.2011.02239.x     

Histomorphometric analysis of newly formed bone after bilateral maxillary sinus augmentation using two different osteoconductive materials and internal collagen membrane

Deproteinized bovine bone mineral (DBBM) and human freeze-dried bone allograft (FDBA) were compared in five patients undergoing bilateral maxillary sinus floor augmentation using DBBM on one side and FDBA on the contralateral side. After 9 months, core biopsy specimens were harvested. Mean newly formed bone values were 31.8% and 27.2% at FDBA and DBBM sites, respectively (P = .451); mean residual graft particle values were 21.5% and 24.2%, respectively (P = .619); and mean connective tissue values were 46.7% and 48.6%, respectively (P = .566). Within the limits of the present study, it is suggested that both graft materials are equally suitable for sinus augmentation.     

Maxillary Sinus Augmentation Using Prehydrated Corticocancellous Porcine Bone: Hystomorphometric Evaluation after 6 Months

Background: Insufficient alveolar bone height often prevents the placement of standard dental implants in the posterior part of edentulous maxilla. In order to increase adequately the vertical dimension of the reabsorbed alveolar process, a sinus lift procedure is often necessary. The aim of this study was to evaluate histologic results of a prehydrated corticocancellous porcine bone used in maxillary sinus augmentation. Methods: Patients (age 18–70 years) with a residual bone height requiring a maxillary sinus augmentation procedure to place dental implants were eligible for this study. All patients were treated with the same surgical technique consisting of sinus floor augmentation via a lateral approach. The space obtained by elevation of the mucosa wall was grafted with prehydrated and collagenated corticocancellous porcine bone. Biopsies were harvested 6 months after the augmentation procedures. Results: Twenty‐four patients were enrolled. The mean percentage of new formed bone was 43.9 ± 18.6% (range 7.5–100%), whereas the mean percentage of residual graft material was 14.2 ± 13.6% (range 0–41.9%). The new bone/residual graft material ratio in the maxillary sinuses was 3.1. The mean soft tissues percentage was 41.8 ± 22.7% (range 0–92.5%). Conclusion: The present study suggested that porcine bone showed excellent osteoconductive properties and could be used successfully for sinus augmentation. Moreover, the porcine bone showed a high percentage of reabsorption after 6 months; this might be because of the presence of collagen and the porosity of the graft material.     

Maxillary sinus augmentation using sinus membrane elevation and peripheral venous blood for implant-supported rehabilitation of the atrophic posterior maxilla: case series

Background Dental implants need appropriate bone volume for adequate stability in the rehabilitation after tooth loss. In the severely atrophic posterior maxilla, the clinical success of implant treatment sometimes requires a vertical ridge augmentation in the maxillary sinus floor. Purpose The purpose of this investigation was to evaluate a maxillary sinus floor augmentation technique using a replaceable bone window, elevation of the membrane, placement of implants, and injection of the patient’s own venous blood to fill the voids. Materials and Methods Six patients with need of maxillary sinus floor augmentation participated in the study. After preparation of a replaceable bone window in the lateral aspect of the sinus and careful elevation of the Schneiderian membrane, a total of 14 Brånemark implants (TiUnite, MK III, Nobel Biocare AB, Göteborg, Sweden) were installed in the residual bone penetrating into the sinus cavity. The sinus cavity was then filled with peripheral venous blood and the bone window replaced and stabilized with a medical tissue glue (Aron Alpha A, Sankyo, Inc., Tokyo, Japan) to prevent blood leakage from the created compartment in the maxillary sinus. Results After a healing period of a minimum of 6 months, new bone was successfully generated in all 14 implant sites as judged from radiographs. One of the 14 implants failed, corresponding to a survival rate of 92.9% after a follow‐up period ranging 12 to 34 months. Conclusions The present case series demonstrate that the creation of a secluded space in the maxillary sinus and filling with venous blood results in bone formation at simultaneously installed dental implants over a 6‐month period.     

Effect of maxillary sinus floor augmentation on sinus membrane thickness in computed tomography

Background: Little is known about maxillary sinus compliance, i.e., the intrinsic potential of the sinus membrane to resume its homeostatic status after the surgical trauma caused by sinus floor elevation. The aim of the present study is to investigate the effect of maxillary sinus floor augmentation on sinus membrane thickness. Methods: Within‐patient comparison of computed tomographic scans before bone grafting versus 4 to 6 months after bone grafting was performed. Changes in membrane thickness were evaluated in 65 maxillary sinus floor augmentation procedures via a lateral approach in 35 patients without clinical signs of sinus pathology at any time. Results: Sinus membrane thickness differed significantly before (0.8 ± 1.2 mm) versus after (1.5 ± 1.3 mm) augmentation surgery (P <0.001), with a mean increase of 0.8 ± 1.6 mm (maximum: 4.4 mm). Only 28% of augmented sinuses did not show membrane thickening. In non‐augmented control sinuses, there was no evidence of membrane thickness increase. Conclusions: The results indicate that the maxillary sinus membrane, even in healthy clinical conditions, undergoes morphologic modifications after sinus floor elevation, yet membrane reactions demonstrate significant variability. Future research on the effect of augmentation surgery on maxillary sinus physiology is recommended.     

The use of a piezoelectric ultrasonic osteotome for internal sinus elevation: a retrospective analysis of clinical results

Purpose: To explore the possibility and evaluate the clinical outcome of accomplishing maxillary internal sinus floor augmentation through the use of a piezoelectric osteotome in conjunction with dental implant placement and to discuss this technique. Materials and Methods: Patients attending the outpatient clinic of the Department of Dental Implantology, Hospital of Stomatology, Tongji University, between July 2007 and September 2009, who had insufficient bone volume to harbor endosseous implants at least 8 mm long in the lateral/posterior maxilla because of sinus pneumatization were enrolled in the study. Sinus augmentations were accomplished with a piezoelectric osteotome, followed by implant placement, either immediately or delayed (6 months after augmentation, if the residual ridge height was less than 4 mm). Results: Thirty patients with 36 maxillary molar sites with insufficient alveolar bone height as a result of pneumatization of the sinus were included in this study. The residual vertical bone height ranged from 2 to 8 mm. Twenty-eight implants were placed into 24 patients immediately after sinus augmentation. Another eight implants were placed into 6 patients 6 months after sinus augmentation. Only one sinus membrane perforated (failure rate: 2.78%). Only one implant was lost during the observation period. No other implant mobility or rapid bone loss was seen during a follow-up period of 5 to 27 months. Conclusions: Application of a piezoelectric osteotome for internal sinus elevation simplified manipulation of the membrane and greatly reduced the chance of perforation. The pressure gradient between sinus and implant cavity was helpful in accomplishing this technique.     

Maxillary sinus augmentation with deproteinated bovine bone and platelet rich plasma with simultaneous insertion of endosseous implants.

PURPOSE: To investigate the clinical applicability of using deproteinated bovine bone mixed with autologous platelet rich plasma (PRP) in human maxillary sinus augmentations in severely resorbed posterior maxillary alveolar processes with simultaneous insertion of endosseous dental implants. MATERIALS AND METHODS: Fifteen patients with less than 5 mm of residual alveolar bone height in the posterior maxillary alveolus underwent a total of 24 maxillary sinus augmentations. Seventy endosseous implants were inserted simultaneously in the grafted sinuses. The implants were uncovered and loaded 4 months after insertion and the sinus augmentation. An osseous biopsy specimen was obtained from the augmented maxillary sinus in 1 patient. In 3 patients, computed tomography scans of the grafted maxillae were obtained and the bone density quantified and compared with native bone density using SIMPlant 7 (Columbia Scientific, Columbia, MD) software 4 months postoperatively. RESULTS: Although a total of 5 implants in 4 patients were lost, this did not result in the loss of any of the restorations, for an overall success rate of 92.9 %. Follow-up for patients in this study after insertion of the permanent restoration was between 6 and 36 months. The bone biopsy from the patients showed evidence of viable new bone formation in close approximation to the xenograft. The bone density of the grafted bone was similar or exceeded the bone density of the surrounding native maxillary bone. CONCLUSION: Based on our clinical experience, we believe that the use of platelet rich plasma in combination with deproteinated bovine bone is effective for maxillary sinus augmentation with simultaneous insertion of endosseous dental implants in severely resorbed posterior maxillae.