Soltani Parisa, Moaddabi Amirhossein, Mehdizadeh Mojdeh, Bateni Mohammad Rez, Naghdi Sepehr, Cernera Mariangela, Mirrashidi Farnaz, Azimipour Mohammad Matin, Spagnuolo Gianrico, Valletta Alessandra
Department of Oral and Maxillofacial Radiology, Dental Implants Research Center, Dental Research Institute, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran.
Department of Neurosciences, Reproductive and Odontostomatological Sciences, University of Naples Federico II, Naples, Italy.
Imaging Sci Dent. 2024 Dec;54(4):313-318. doi: 10.5624/isd.20240029. Epub 2024 Aug 25.
This study aimed to evaluate the impact of a metal artifact reduction (MAR) algorithm on cone-beam computed tomography (CBCT) scans of titanium and zirconia implants, both within and outside the field of view (FOV).
In this study, a dry human mandible was positioned in a CBCT scanner with only its left quadrant included in the FOV. Each type of implant (titanium and zirconia) was placed once in the right second premolar extraction socket and once in the left second premolar extraction socket of the mandible. CBCT scans were acquired with and without MAR. Three regions of interest (ROIs) were defined in relation to a resin block, and the contrast-to-noise ratio (CNR) was calculated for each ROI. Data were analyzed using 2-way analysis of variance with an alpha level of 0.05.
Application of a MAR algorithm significantly increased the CNR within and outside the FOV for both implant types (<0.05). Relative to titanium implants, zirconia implants were associated with significantly lower CNRs in both positions (<0.05) and generated more artifacts. Implant placement outside the FOV was associated with slightly lower image quality than positioning within the FOV, although this finding was not significant (>0.05).
The results suggest that application of a MAR algorithm in CBCT significantly impacts artifact generation. Titanium implants exhibited significantly lower metal artifact generation compared to zirconia implants. Positioning either implant type outside the FOV, as opposed to inside it, slightly increased artifact generation; however, this was not statistically significant.
本研究旨在评估金属伪影减少(MAR)算法对锥束计算机断层扫描(CBCT)中钛和氧化锆种植体的影响,包括在视野(FOV)内和视野外的情况。
在本研究中,将一个干燥的人类下颌骨放置在CBCT扫描仪中,仅其左象限包含在视野内。每种类型的种植体(钛和氧化锆)分别放置在下颌骨右侧第二前磨牙拔牙窝和左侧第二前磨牙拔牙窝各一次。在有和没有MAR的情况下进行CBCT扫描。相对于一个树脂块定义了三个感兴趣区域(ROI),并计算每个ROI的对比噪声比(CNR)。使用双因素方差分析对数据进行分析,α水平设定为0.05。
对于两种种植体类型,应用MAR算法均显著提高了视野内和视野外的CNR(P<0.05)。相对于钛种植体,氧化锆种植体在两个位置的CNR均显著较低(P<0.05),并且产生更多伪影。种植体放置在视野外时的图像质量略低于放置在视野内时,尽管这一发现不具有统计学意义(P>0.05)。
结果表明,在CBCT中应用MAR算法对伪影产生有显著影响。与氧化锆种植体相比,钛种植体产生的金属伪影明显更少。将任何一种种植体类型放置在视野外而非视野内,会略微增加伪影产生;然而,这在统计学上并不显著。