目的:评估使用结缔组织移植物(CTG)进行种植体周围软组织增强后,牙齿和种植体部位的超声组织弹性及其变化。
方法:28名患者,每个都有一个临床健康的牙科植入物表现出软组织裂开(PSTD),包括在内。植入部位用CTG扩增并监测超过12个月。超声应变弹性成像,表示为应变比(分别为SR1,SR2和SR3)在基线评估,6-,12个月,并与相应的对侧同源天然牙进行比较。与天然牙冠/植入物支撑的牙冠相比,SR1评估了软组织中面冠部的应变/弹性。SR2评估了中面冠状软组织相对于肺泡粘膜的应变,而SR3在横向超声扫描中描绘了中面软组织相对于邻间软组织的应变。
结果:天然牙列和植入部位的SR1分别为0.20±0.08和0.30±0.14(p=.002),表明牙齿周围软组织的冠状部分通常比牙种植体周围的对应部分更有弹性。在12个月内,用CTG增强软组织的中面冠状部分的硬度增加(SR1,SR2和SR3的p<0.001)。在12个月时间点的应变比率显著高于在6个月时观察到的值(p<.001)。回归分析表明,自然牙列中的应变弹性成像比率与角化牙龈宽度显着相关,和牙龈厚度。在植入部位,SR1与角化粘膜宽度和粘膜厚度显著相关(p<0.001),SR2与角化粘膜宽度显著相关(p=0.013),SR3与联合CTG进行的手术技术显着相关(p=0.022)。
结论:超声应变弹性成像可捕获并量化软组织增强后的组织弹性及其变化。在软组织的最冠状方面,在牙齿和牙植入物之间观察到不同的基线组织弹性。影响组织弹性相关结局的主要因素是角化组织宽度,和粘膜厚度。
OBJECTIVE: To assess ultrasonographic tissue elasticity at teeth and implant sites and its variation after peri-implant soft tissue augmentation with a connective tissue graft (CTG).
METHODS: Twenty-eight patients, each contributing with one clinically healthy dental implant exhibiting a soft tissue dehiscence (PSTD), were included. Implant sites were augmented with CTG and monitored over 12 months. Ultrasonographic strain elastography, expressed as strain ratios (SR1, SR2, and SR3, respectively) was assessed at baseline, 6-, and 12-month, and compared with the corresponding contralateral homologous natural tooth. SR1 assessed the strain/elasticity of the midfacial coronal portion of the soft tissue in comparison to the natural tooth crown/implant-supported crown, SR2 evaluated the strain of the midfacial coronal soft tissue in relation to the one of the alveolar mucosa, while SR3 depicted the strain of the midfacial soft tissue in relation to the interproximal soft tissue on the transverse ultrasound scan.
RESULTS: SR1 in natural dentition and at implant sites was 0.20 ± 0.08 and 0.30 ± 0.14, respectively (p = .002), indicating that the coronal portion of the soft tissue around teeth is generally more elastic than its counterpart around dental implants. Soft tissue augmentation with CTG promoted an increased stiffness of the midfacial coronal portion of the soft tissue over 12 months (p < .001 for SR1, SR2, and SR3). Strain ratios at the 12-month time points were significantly higher than the values observed at 6 months (p < .001). Regression analysis demonstrated that strain elastography ratios in natural dentition were significantly associated with keratinized gingiva width, and gingival thickness. At implant sites, SR1 was significantly associated with keratinized mucosa width and mucosal thickness (p < .001 for both correlations), SR2 was significantly associated with keratinized mucosa width (p = .013), and SR3 was significantly associated with the surgical technique performed in combination with CTG (p = .022).
CONCLUSIONS: Ultrasound strain elastography captures and quantifies tissue elasticity and its changes after soft tissue augmentation. A different baseline tissue elasticity was observed between teeth and dental implants in the most coronal aspect of the soft tissue. The main factors affecting tissue elasticity-related outcomes were the keratinized tissue width, and mucosal thickness.