Review of Risk Assessment of Major Anatomical Variations in Clinical Dentistry

Most of the studies of the mandible's anatomical variations have presented the authors' speculations, and only a limited number has provided evidence that demonstrated the actual complications injury to the variant structures caused. To our knowledge, no study has evaluated the risks associated with these variant anatomical structures' injury. We reviewed articles that described clinical cases of the injury to, and anatomical studies of, three anatomical variants of the mandible—the accessory mental, lingual, and retromolar foramina—with which dentists are relatively familiar and that are mentioned often in the context of implant and third molar surgeries, to describe risk assessment methods with which to evaluate potential complications preoperatively. Only a limited number of the clinical reports of injury to the mandible's accessory foramina were available. The potential severe complication of injury of the accessory mental foramen (AMF) is sensory disturbance of the lower lip. Risk of neurosensory disturbance of lower lip can be assessed by AMF/MF ratio and positional relations to the MF. Potential severe complication of injury of the lingual foramen is bleeding and hemorrhage in the oral cavity's floor. Risk of bleeding can be assessed by diameter and positional relation between the mental spine/mylohyoid line. A risk assessment of the retromolar foramen could not be made because of inadequate data. We hope the risk assessments suggested will encourage dentists to predict intraoperative/postoperative complications caused by damaging the mandible's accessory foramina. Clin. Anat. 32:672–677, 2019. © 2019 Wiley Periodicals, Inc.     

Short implants (≤8 mm) compared to standard length implants (>8 mm) in conjunction with maxillary sinus floor augmentation: a systematic review and meta-analysis

The objective was to test the hypothesis of no difference in the treatment outcome after the installation of short implants (≤8 mm) in the posterior part of the maxilla compared to standard length implants (>8 mm) in conjunction with maxillary sinus floor augmentation (MSFA) using the lateral window technique, after an observation period of ≥3 years. A search of the MEDLINE, Embase, and Cochrane Library databases, in combination with a hand-search of relevant journals, was conducted. The search yielded 1102 titles. Finally, three studies that fulfilled the inclusion criteria were included. All were considered to have a low risk of bias. Meta-analyses revealed no significant differences in implant survival or peri-implant marginal bone loss between the two treatment modalities. However, the use of standard length implants in conjunction with MSFA was characterized by a tendency towards more peri-implant marginal bone loss. There was no statistically significant difference between the two treatment modalities with regard to overall patient satisfaction. Short implants seem to be a suitable alternative to standard length implants in conjunction with MSFA. However, further randomized controlled trials with larger patient samples and an observation period of more than 3 years are needed before one treatment modality might be considered superior to the other.     

微弧氧化技术与钛合金表面成骨细胞增殖及骨向分化能力

文题释义：微弧氧化技术：是金属材料表面处理的一种技术，将金属材料(如，镁、铝、钛等)置于特定电解液中，通过弧光放电过程中瞬时的高温和高压条件产生结合于金属表面的陶瓷膜层，该种方法制备的涂层材料具有高硬度、耐磨的特点。  种植体：是针对于人体自身牙齿缺失而植入上下颌骨内的人工牙根。性能优良的种植体需要同时具备高强度、耐降解、生物相容性好的特性。目前复合材料类如金属表面添加陶瓷涂层材料，具有上述多种材料特性而被临床选择。 背景：采用普通电化学法可在钛及其合金表面制备纳米级羟基磷灰石涂层，但该涂层吸收降解缓慢，需要8-12周的时间。而微弧氧化可在复杂表面形成均匀薄膜，有利于细胞黏附和骨组织长入。 目的：探索微弧氧化羟基磷灰石涂层钛合金对成骨细胞增殖及骨向分化能力的影响。 方法：采用电化学法与微弧氧化法分别制备羟基磷灰石涂层钛合金材料，检测两种材料表面的接触角。将成骨细胞系hFOB1.19接种于两组羟基磷灰石涂层钛合金材料表面，培养48 h时，采用扫描电镜观察细胞在材料上的形态变化；培养1，12，24，48，72 h时，采用MTT法检测细胞增殖；培养1，3，5 d时，比较两组材料表面细胞计数与碱性磷酸活性；培养第5天，采用Western Blotting检测细胞内骨形态发生蛋白2和骨形态发生蛋白4表达。 结果与结论：①微弧氧化组材料表面的接触角小于电化学组[(66.5±2.2)°，(52.8±2.1)°，P=0.001 5)]；②扫描电镜显示，电化学组成骨细胞形态不规则，胞体皱缩不饱满，与材料贴合较差；微弧氧化组细胞充分伸展，形态扁平，与材料贴合紧密；③微弧氧化组12-72 h的细胞增殖快于电化学组(P < 0.05)，培养3，5 d的细胞计数多于电化学组(P < 0.05)；④微弧氧化组培养1，3，5 d的细胞碱性磷酸酶活性高于电化学组(P < 0.05)；⑤微弧氧化组骨形态发生蛋白2和骨形态发生蛋白4表达均高于电化学组(P < 0.05)；⑥结果表明，微弧氧化羟基磷灰石涂层钛合金材料可促进成骨细胞的增殖及骨向分化能力。 ORCID: 0000-0003-2787-4667(王艳玲) 中国组织工程研究杂志出版内容重点：生物材料；骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性；组织工程     

数字化口腔种植外科导板的精确度研究

目的本研究通过分析种植体术前设计和术后的三维位置,来评估数字化口腔种植导板的精确度。方法根据修复体的生物学功能和美学要求,使用3D种植软件对种植体位置进行设计。将设计的种植导板转化为手术用种植导板,指导47颗种植体植入合适位置。通过重叠术前和术后的CT扫描图像,分析植体肩部和根部的线性误差以及植体长轴的角度误差,比较植体设计和实际植入的3D位置。结果通过比较47颗种植体发现,种植体肩部的平均误差为(0.58±0.23)mm,种植体根部的平均误差为(0.66±0.30)mm,而角度平均误差为(2.40±1.02)°。结论与传统种植手术相比,数字化无翻瓣种植技术为临床医生提供方便;然而,为确保可预测的治疗结果,精确的术前设计是必须的,如此才不会导致可能出现的术中和术后并发症。