目的评价浓缩生长因子(concentrated growth factor,CGF)应用于上颌前牙区唇侧骨缺损引导骨再生(guided bone regeneration,GBR)的效果。方法选取上颌前牙区单牙缺失伴唇侧水平向骨缺损40例,随机分为观察组和对照组各20例。观察组使用...目的评价浓缩生长因子(concentrated growth factor,CGF)应用于上颌前牙区唇侧骨缺损引导骨再生(guided bone regeneration,GBR)的效果。方法选取上颌前牙区单牙缺失伴唇侧水平向骨缺损40例,随机分为观察组和对照组各20例。观察组使用浓缩生长因子+骨粉+胶原膜行引导骨再生术;对照组使用骨粉+胶原膜行常规引导骨再生术。术后行软组织愈合评估,术后半年评价骨增量的效果。结果观察组软组织伤口一期愈合率为100%,对照组为75%,观察组高于对照组,差异具有统计学意义(P=0.017)。观察组术后半年骨宽度增加量为(3.70±0.28)mm,对照组为(2.96±0.16)mm,观察组骨增量大于对照组,差异具有统计学意义(P=0.000)。结论 CGF能促进上颌前牙区骨缺损引导骨再生术的成骨量。展开更多
目的:探讨分析上颌前牙美学区种植修复使用角度基台的影响因素。方法:建立仿真模型,运用三维有限元法(Finite Element Method,FEM)分析4.0mm直径、10mm和13mm长度(Length,L)的种植体连接不同角度基台(0°、10°、20°、30&#...目的:探讨分析上颌前牙美学区种植修复使用角度基台的影响因素。方法:建立仿真模型,运用三维有限元法(Finite Element Method,FEM)分析4.0mm直径、10mm和13mm长度(Length,L)的种植体连接不同角度基台(0°、10°、20°、30°)的生物力学性能。结果:随着基台角度增大,种植修复系统、皮质骨、松质骨各部位应力及应变递增,分布更集中;与0°角度基台对比,使用30°角度基台可增加34.8%(L13mm)、39.5%(L10mm)的皮质骨区最大应力,增加18.1%(L13mm)、39.6%(L10mm)的松质骨区最大应力;同时,皮质骨区最大应变增加64.0%(L13mm)、64.4%(L10mm),松质骨区最大应变增加23.9%(L13mm)、57.2%(L10mm);种植体长度增加3mm,皮质骨和松质骨周围最大应力能减少10.6%～18.2%,皮质骨区的最大弹性形变减少2.1%～2.2%,松质骨区的最大弹性形变减少17.9%～25.4%;负载下,各组模型在连接接近20°角度基台时,皮质骨应变已接近骨弹性阈值。结论:基台角度越大,种植系统及牙槽骨所受应力、应变越大越集中;上前牙区4mm直径种植体建议连接小于20°的角度基台,以减少局部皮质骨应力应变;增加种植体长度一定程度上可减小应力和分散应变。展开更多
Although short implants are seen as alternative treatments that require additional surgical techniques in posterior region, they can be applied to anterior maxilla and various studies are required on this subject. The...Although short implants are seen as alternative treatments that require additional surgical techniques in posterior region, they can be applied to anterior maxilla and various studies are required on this subject. The purpose of this study was to examine and compare the peak von Mises stress distributions in the crown, implant and abutment by using finite element analysis (FEA). Besides, a comparison of the implant-abutment connection types in the short implant with the FEA method was established. A short implant (4 × 5 mm) with a taper-lock connection and a regular implant (4 × 9 mm) with a screw connection were used in maxillary central incisor tooth area. Three different titanium abutments with 0?, 15? and 25? angles were used for abutments. In addition, in order to determine whether the stress change in short implants is due to the length of the implant-abutment connection, a screw was designed for a short implant and it was also evaluated in the same three angles. A total of three groups and nine models were generated. 114.6N load was applied to the cingulum area of the crown at an angle of 135? to the long axis of the crowns. A torque load of 25 Ncm was applied to the regular and short implant screw. Von Mises stress distributions of implants, abutments and crowns were evaluated by using FEA. Increased angle in implants increased von Mises stress values of implant, abutment and crown. Screw connection was found higher at all angles in short implants. Close values were found at different angles in taper-lock short implant crowns. The length and the angle in the bone of implant with the type of implant-abutment connection results in the accumulated stress values. Clinical Implications Taper implant-abutment connection system was found to be more promising in terms of stress accumulation in crowns. Although the amount of stress on the abutment increased due to the length of the implant in short implants, taper implant-abutment connection system slightly reduced related to this increase.展开更多
The aim of this study was to compare the bone resorption differences between implant placement sites (IPS) and non-implant placement sites (NIPS) after autogenous block bone grafts in the anterior maxilla. Fourteen pa...The aim of this study was to compare the bone resorption differences between implant placement sites (IPS) and non-implant placement sites (NIPS) after autogenous block bone grafts in the anterior maxilla. Fourteen patients (58 edentulous sites) with alveolar atrophy in the anterior maxilla were treated with autogenous block bone grafts. CBCT examinations were performed at 1 month before surgery (T0), immediately after surgery (T1), 3 to 4 months after surgery (T2), 6 to 7 months after surgery before implant placement (T3), 12 to 13 months after surgery (T4), and the longest follow-up point (T5). Alveolar crestal and basal bone width (ACBW, ABBW), and alveolar bone height (ABH) were measured and divided into IPS (30 sites) and NIPS (28 sites). All results were compared by the Wilcoxon Signed Rank test. The bone resorption changes for both groups were the same. For these three parameters, ACBW didn’t change significantly from T2 to T3 and T4 to T5, ABBW didn’t change at every period from T2 to T5, and ABH didn’t change from T4 to T5. The bone resorption volume of ACBW and ABH in NIPS were more than in IPS after implant placement surgery, while the volume of ABBW was similar in both groups. At T5, the bone resorption percentages of ACBW, ABBW, and ABH were 25.57%, 16.85% and 43.84% in IPS, and 33.55%, 15.92% and 46.44% in NIPS. A more rapid loss of alveolar crest in NIPS resulted from implant placement surgery, and this reminded us of the importance of immediate implant placement.展开更多
文摘目的:探讨分析上颌前牙美学区种植修复使用角度基台的影响因素。方法:建立仿真模型,运用三维有限元法(Finite Element Method,FEM)分析4.0mm直径、10mm和13mm长度(Length,L)的种植体连接不同角度基台(0°、10°、20°、30°)的生物力学性能。结果:随着基台角度增大,种植修复系统、皮质骨、松质骨各部位应力及应变递增,分布更集中;与0°角度基台对比,使用30°角度基台可增加34.8%(L13mm)、39.5%(L10mm)的皮质骨区最大应力,增加18.1%(L13mm)、39.6%(L10mm)的松质骨区最大应力;同时,皮质骨区最大应变增加64.0%(L13mm)、64.4%(L10mm),松质骨区最大应变增加23.9%(L13mm)、57.2%(L10mm);种植体长度增加3mm,皮质骨和松质骨周围最大应力能减少10.6%～18.2%,皮质骨区的最大弹性形变减少2.1%～2.2%,松质骨区的最大弹性形变减少17.9%～25.4%;负载下,各组模型在连接接近20°角度基台时,皮质骨应变已接近骨弹性阈值。结论:基台角度越大,种植系统及牙槽骨所受应力、应变越大越集中;上前牙区4mm直径种植体建议连接小于20°的角度基台,以减少局部皮质骨应力应变;增加种植体长度一定程度上可减小应力和分散应变。
文摘Although short implants are seen as alternative treatments that require additional surgical techniques in posterior region, they can be applied to anterior maxilla and various studies are required on this subject. The purpose of this study was to examine and compare the peak von Mises stress distributions in the crown, implant and abutment by using finite element analysis (FEA). Besides, a comparison of the implant-abutment connection types in the short implant with the FEA method was established. A short implant (4 × 5 mm) with a taper-lock connection and a regular implant (4 × 9 mm) with a screw connection were used in maxillary central incisor tooth area. Three different titanium abutments with 0?, 15? and 25? angles were used for abutments. In addition, in order to determine whether the stress change in short implants is due to the length of the implant-abutment connection, a screw was designed for a short implant and it was also evaluated in the same three angles. A total of three groups and nine models were generated. 114.6N load was applied to the cingulum area of the crown at an angle of 135? to the long axis of the crowns. A torque load of 25 Ncm was applied to the regular and short implant screw. Von Mises stress distributions of implants, abutments and crowns were evaluated by using FEA. Increased angle in implants increased von Mises stress values of implant, abutment and crown. Screw connection was found higher at all angles in short implants. Close values were found at different angles in taper-lock short implant crowns. The length and the angle in the bone of implant with the type of implant-abutment connection results in the accumulated stress values. Clinical Implications Taper implant-abutment connection system was found to be more promising in terms of stress accumulation in crowns. Although the amount of stress on the abutment increased due to the length of the implant in short implants, taper implant-abutment connection system slightly reduced related to this increase.
文摘The aim of this study was to compare the bone resorption differences between implant placement sites (IPS) and non-implant placement sites (NIPS) after autogenous block bone grafts in the anterior maxilla. Fourteen patients (58 edentulous sites) with alveolar atrophy in the anterior maxilla were treated with autogenous block bone grafts. CBCT examinations were performed at 1 month before surgery (T0), immediately after surgery (T1), 3 to 4 months after surgery (T2), 6 to 7 months after surgery before implant placement (T3), 12 to 13 months after surgery (T4), and the longest follow-up point (T5). Alveolar crestal and basal bone width (ACBW, ABBW), and alveolar bone height (ABH) were measured and divided into IPS (30 sites) and NIPS (28 sites). All results were compared by the Wilcoxon Signed Rank test. The bone resorption changes for both groups were the same. For these three parameters, ACBW didn’t change significantly from T2 to T3 and T4 to T5, ABBW didn’t change at every period from T2 to T5, and ABH didn’t change from T4 to T5. The bone resorption volume of ACBW and ABH in NIPS were more than in IPS after implant placement surgery, while the volume of ABBW was similar in both groups. At T5, the bone resorption percentages of ACBW, ABBW, and ABH were 25.57%, 16.85% and 43.84% in IPS, and 33.55%, 15.92% and 46.44% in NIPS. A more rapid loss of alveolar crest in NIPS resulted from implant placement surgery, and this reminded us of the importance of immediate implant placement.
