Nicole Winitsky^1,2,*; Aron Naimi-Akbar³; Robert Nedelcu⁴; Torsten Jemt^5,6; Jan-Ivan Smedberg^7,8

¹Department of Prosthetic Dentistry, Folktandvården Stockholm AB, Folktandvården Eastmaninstitutet; ²Division of Prosthetic Dentistry, Department of Dental Medicine, Karolinska Institutet, Stockholm; ³Health Technology Assessment-Odontology (HTA-O), Malmö University, Malmö; ⁴Department of Surgical Sciences, Plastic and Oral and Maxillofacial Surgery, Uppsala University, Uppsala; ⁵Department of Prosthetic Dentistry/Dental Material Science, Institute of Odontology, Sahlgrenska Academy at Gothenburg University; ⁶Brånemark Clinic, Public Dental Health Service, Region of Västra Götaland, Göteborg; ⁷Department of Prosthetic Dentistry, Folktandvården Eastmaninstitutet, Folktandvården Stockholms län AB; ⁸Department of Prosthetic Dentistry/Dental Material Science, Karolinska Institutet, Stockholm, Sweden

Background: In light of the large and increasing number of single implants inserted globally, surprisingly few studies have focused on the long-term (i.e., > 15 years) outcome of such treatment. Single anterior implants are predominantly placed in young patients with long remaining lifetime and infraposition in relationship to adjacent teeth has been observed in both younger and older patients. The treatment modality requires more knowledge regarding long-term positional changes and esthetic outcome.

Aim/Hypothesis: To report three-dimensional (3-D) movement of teeth adjacent to single implants in the anterior maxilla and to explore and estimate the potential associations with patient-related variables as well as to objective and subjective esthetic evaluation.

Material and Methods: 3-D movements of teeth adjacent to single anterior maxillary implant crowns were measured after 14 to 20 years in function. Dental casts from baseline (crown delivery) and follow-up examination from 30 patients, with a mean age of 21 years, were digitalized and aligned using a software program. The vertical (incisal) movements were related to patient and implant characteristics such as facial type, lower anterior facial height (LAFH), age at crown delivery, sex, the position of the implant, implant occlusion, cause of tooth loss, follow-up period, orthodontic treatment prior to implant placement and marginal bone level changes. The esthetic outcome was assessed using Visual Analogue Scale (VAS) and California Dental Association index (CDA). Correlation between tooth movements in 3-D (incisal, mesio-distal and bucco-palatal) as well as possible agreement between the VAS ratings of the clinicians and the patients were evaluated.

Results: The average rate of incisal tooth movement was 0.05 mm/year. 3-D movements of teeth adjacent to the implant crowns ranged from 0.2 to 2.3 mm during follow-up. Movements in an incisal and palatal direction were most pronounced and found to be correlated. Teeth adjacent to implants in the central incisor position exhibited a mean incisal movement of 0.5 ± 0.3 mm, while teeth adjacent to implants in lateral incisor or canine position each exhibited a mean incisal movement of 1.0 ± 0.5 mm. “Implants in central incisor position” and “implants in occlusion” were significantly associated with less incisal adjacent tooth movements. Incisal tooth movements of > 1 mm (30 %) were significantly associated with LAFH ≥ 70 mm. The esthetic VAS ratings associated poorly between patients (mean rating 85%) and clinicians (mean rating 67%) with Kappa index of 0.09 (“low agreement”). The CDA rating was assessed as satisfactory in 87% of the patients.

Conclusion and Clinical implications: Although infraposition occurs, patients are highly satisfied with and rates the esthetics of their implants higher than dentists. Risk assessment for infraposition may in the future focus more on individual patient related predictors than age at implant placement. It seems appropriate to always inform the patients, prior to treatment, about the possible need for replacement of implant crowns due to implant infraposition. This is yet another reason to perform screw retained implant crowns.

Disclosure of Interest: N. Winitsky Conflict with: Nobel Biocare, Conflict with: Nobel Biocare, Conflict with: Nobel Biocare, A. Naimi-Akbar: None Declared, R. Nedelcu Conflict with: Nobel Biocare, Conflict with: Nobel Biocare, Conflict with: Nobel Biocare, T. Jemt Conflict with: Nobel Biocare, Conflict with: Nobel Biocare, Conflict with: Nobel Biocare, J.-I. Smedberg: None Declared

Keywords: aesthetic zone

妮可·温尼茨基^1,2,* ; Aron Naimi-Akbar ³ ; 罗伯特·内德尔库⁴ ; Torsten Jemt ^5,6 ; 扬-伊万·斯梅德伯格^7,8

¹修复牙科系，Folktandvården Stockholm AB，Folktandvården Eastmaninstitutet；²斯德哥尔摩卡罗林斯卡医学院牙科医学系修复牙科部；³健康技术评估-牙科学 (HTA-O)，马尔默大学，马尔默；⁴乌普萨拉大学外科科学、整形和口腔颌面外科系，乌普萨拉；⁵哥德堡大学Sahlgrenska学院牙学研究所修复牙科/牙科材料科学系；⁶ Brånemark Clinic, Public Dental Health Service, Västra Götaland, Göteborg；⁷修复牙科系，Folktandvården Eastmaninstitutet，Folktandvården Stockholms län AB；⁸修复牙科/牙科材料科学系，瑞典斯德哥尔摩卡罗林斯卡医学院

背景：鉴于全球植入的单个种植体数量庞大且不断增加，令人惊讶的是，很少有研究关注此类治疗的长期（即 > 15 年）结果。单一前牙种植体主要放置在剩余寿命较长的年轻患者中，并且在年轻和年长患者中都观察到与相邻牙齿相关的下位。治疗方式需要更多关于长期体位变化和美学效果的知识。

目的/假设：报告上颌前牙单个种植体附近牙齿的三维 (3-D) 运动，探索和估计与患者相关变量以及客观和主观美学评估的潜在关联。

材料与方法：在功能 14 至 20 年后测量与单个前上颌种植体牙冠相邻的牙齿的 3-D 运动。使用软件程序对 30 名平均年龄为 21 岁的患者的基线（牙冠分娩）和后续检查的牙科模型进行数字化和对齐。垂直（切端）运动与患者和种植体特征有关，例如面部类型、前面部下高 (LAFH)、牙冠分娩年龄、性别、种植体位置、种植体咬合、牙齿脱落原因、随访期间、种植体植入前的正畸治疗和边缘骨水平变化。使用视觉模拟量表 (VAS) 和加州牙科协会指数 (CDA) 评估美学结果。3-D 中牙齿运动之间的相关性（切缘、

结果：切牙移动的平均速率为 0.05 毫米/年。在随访期间，与种植体冠相邻的牙齿的 3-D 移动范围为 0.2 至 2.3 毫米。切缘和腭方向的运动最为明显，并发现相关性。与中切牙位置的种植体相邻的牙齿的平均切向移动量为 0.5 ± 0.3 毫米，而与位于侧切牙或尖牙位置的种植体相邻的牙齿的平均切向移动量为 1.0 ± 0.5 毫米。“中切牙位置的种植体”和“咬合中的种植体”与较少的切端邻牙移动显着相关。切端牙齿移动 > 1 mm (30 %) 与 LAFH ≥ 70 mm 显着相关。Kappa 指数为 0 的患者（平均评分 85%）和临床医生（平均评分 67%）之间的美学 VAS 评分相关性较差。09（“低一致性”）。87% 的患者的 CDA 评级被评估为满意。

结论和临床意义：虽然发生了下颌角，但患者对种植体的美观度非常满意，并且对种植体的美学评价高于牙医。未来下位风险评估可能更多地关注个体患者相关的预测因素，而不是种植体植入时的年龄。在治疗前始终告知患者可能需要更换种植体牙冠似乎是合适的。这是进行螺钉固定种植体冠的另一个原因。

利益披露：N. Winitsky 与：Nobel Biocare 发生冲突，与：Nobel Biocare 发生冲突，与：Nobel Biocare，A. Naimi-Akbar：无声明，R. Nedelcu 与：Nobel Biocare 发生冲突，与：Nobel Biocare 发生冲突，发生冲突与：Nobel Biocare, T. Jemt 与：Nobel Biocare 有冲突，与：Nobel Biocare 有冲突，与：Nobel Biocare，J.-I. 有冲突。斯梅德伯格：未申报

关键词：审美区