Department of Prosthodontics, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing Key Laboratory of Digital Stomatology, No. 22 Zhongguancun South Avenue, Haidian District, Beijing, 100081, China.
Department of Prosthodontics, Martin-Luther-University Halle-Wittenberg, Halle, Saale, Germany.
BMC Oral Health. 2020 Oct 21;20(1):288. doi: 10.1186/s12903-020-01283-4.
To evaluate the accuracy of a computer numerical control (CNC) milled surgical guide for implant placement in edentulous jaws.
Edentulous patients seeking implants treatment were recruited in this prospective cohort study. Radiographic guides with diagnostic templates were fabricated from wax-up dentures. Patients took cone-beam computed tomography (CBCT) wearing the radiopaque radiographic guides. Implant positions were virtually designed in the planning software based on the CBCT data, and the radiographic templates were converted into surgical guides using CNC milling technique. Forty-four implants were placed into 12 edentulous jaws following guided implant surgery protocol. Post-surgery CBCT scans were made for each jaw, and the deviations between the planned and actual implant positions were measured. Deviation of implant position was compared between maxilla and mandible, and between cases with and without anchor pins using independent t-test.
Nine patients (3 males and 6 females) with 12 edentulous jaws were recruited. The mean age of patients was 59.2 ± 13.9 years old. All 44 implants was placed without complication and survived, the mean three dimensional linear deviation of implant position between virtual planning and actual placement was 1.53 ± 0.48 mm at the implant neck and 1.58 ± 0.49 mm at the apex. The angular deviation was 3.96 ± 3.05 degrees. No significant difference was found in the deviation of implant position between maxilla and mandible (P = 0.28 at neck, 0.08 at apex), nor between cases with and without anchor pins (P = 0.87 at neck, 0.06 at apex).
The guides fabricated using the CNC milling technique provided comparable accuracy as those fabricated by Stereolithography. The displacement of the guides on edentulous arch might be the main contributing factor of deviation.
Chinese Clinical Trial Registry, ChiCTR-ONC-17014159 (July 26, 2017).
评估用于无牙颌种植体植入的计算机数控（CNC）铣削手术导板的准确性。
本前瞻性队列研究招募了寻求种植体治疗的无牙颌患者。从蜡基义齿制作带有诊断模板的放射导板。患者佩戴不透射线的放射导板进行锥形束 CT（CBCT）检查。根据 CBCT 数据，在规划软件中虚拟设计种植体位置，并使用 CNC 铣削技术将放射模板转换为手术导板。根据引导种植体手术方案，将 44 枚种植体植入 12 个无牙颌中。每个颌骨术后均行 CBCT 扫描，测量计划种植体位置与实际种植体位置之间的偏差。采用独立 t 检验比较上颌和下颌、有和无定位钉病例之间的种植体位置偏差。
共纳入 9 名患者（3 名男性和 6 名女性）和 12 个无牙颌。患者的平均年龄为 59.2±13.9 岁。所有 44 枚种植体均无并发症且存活，虚拟规划与实际植入之间种植体位置的三维线性偏差在种植体颈部为 1.53±0.48mm，在根尖为 1.58±0.49mm。角度偏差为 3.96±3.05 度。上颌和下颌之间的种植体位置偏差（颈部 P=0.28，根尖 P=0.08）以及有和无定位钉病例之间的偏差（颈部 P=0.87，根尖 P=0.06）均无统计学差异。
使用 CNC 铣削技术制作的导板与立体光刻技术制作的导板具有相当的准确性。无牙颌弓上导板的移位可能是偏差的主要影响因素。
中国临床试验注册中心，ChiCTR-ONC-17014159（2017 年 7 月 26 日）。
