Eliasson Alf
Department of Prosthetic Dentistry, Institute of Odontology, Sahlgrenska Academy, University of Gothenburg.
Swed Dent J Suppl. 2008(197):3-95.
The aims of this thesis were to analyze reduced number of implants supporting full arch fixed mandibular prostheses and fixed partial dentures (FPDs), non-submerged healing and early loading in the edentulous mandible. A further aim was to evaluate fit of Computer Numerical Controlled (CNC) milled I-Bridge frameworks.
MATERIAL & METHODS: Paper I. One hundred and nineteen patients rehabilitated with full arch mandibular prostheses supported by four implants were evaluated after a mean follow-up of 4.4 years. Paper II. A total of 178 patients provided with FPDs supported by two (n=92) or three implants (n=122) of whom 123 were evaluated after a mean follow-up of 9.4 years. Paper III. Early and delayed loading of full arch mandibular prostheses were evaluated in 109 patients, 54 with delayed loading and 55 with early loading, with a mean follow-up of 3.6 years. Paper IV. Submerged and non-submerged implant placement for supporting fixed prostheses in the edentulous mandible were evaluated after five years in 29 patients. Paper V. The precision of fit of CNC-milled I-Bridge frameworks was evaluated using two different implant systems.
Paper I. The five-year cumulative survival rate (CSR) for implants was 99.1% and for prostheses 100%. Mean bone loss from baseline to five-year follow-up was 0.5 mm. No indication could be found that the number of supporting implants influenced the prosthetic complications. Paper II. The five-year implant and prosthesis CSR was 97.7% for two-implant supported FPDs and 97.3% for three-implant supported FPDs. Mean bone loss at five years was 0.4 mm. Significantly more prosthetic and abutment screw loosening were seen in two-implant supported FPDs. Paper III. Five-year CSR for implants was 94.4% and 92.5% for prostheses in early loading, and 97.9% and 98.0% in the delayed loading group. More prostheses needed adjustment or replacement in the early group, but patients treated with early loading were more pleased with the treatment procedure. Paper IV. Five-year CSR survival rate was 99.4%. Three implants fractured in one patient. Mean bone loss at five years was 0.7 mm in submerged implants and 0.5 mm in non-submerged implants. Paper V. All frameworks demonstrated clinically acceptable fit with mean distortion values within 23 microm (x-axis), 26 microm (y), 4 microm (z- axis) and 34 microm (3-D) for all frameworks. Control frameworks displayed greater levels of distortion than frameworks produced in a strict test situation.
A reduction of the number of supporting implants to four implants in full arch mandibular prostheses and two implants in three unit FPDs in partial edentulous jaws resulted in the same clinical outcome as when more implants are used. Non-submerged implant placement in the edentulous mandible was as predictable as submerged, but early loading of implant-supported mandibular prostheses incurred more prosthetic complications. Computer numerical controlled milled frameworks presented levels of precision of fit within limits considered to be clinically acceptable and superior to earlier published results on cast frameworks.
本论文的目的是分析用于支持全牙弓固定下颌修复体和固定局部义齿（FPD）的种植体数量减少、无牙下颌的非潜入式愈合和早期负载情况。另一个目的是评估计算机数控（CNC）铣削的I型桥支架的适配性。
论文一。对119例采用4枚种植体支持全牙弓下颌修复体的患者进行了评估，平均随访4.4年。论文二。共有178例患者接受了由2枚（n = 92）或3枚种植体（n = 122）支持的FPD，其中123例在平均随访9.4年后进行了评估。论文三。对109例患者的全牙弓下颌修复体进行了早期和延迟负载评估，54例为延迟负载，55例为早期负载，平均随访3.6年。论文四。对29例患者在5年后评估了用于支持无牙下颌固定修复体的潜入式和非潜入式种植体植入情况。论文五。使用两种不同的种植体系统评估了CNC铣削的I型桥支架的适配精度。
论文一。种植体的5年累积生存率（CSR）为99.1%，修复体为100%。从基线到5年随访的平均骨吸收为0.5mm。未发现支持种植体的数量对修复并发症有影响。论文二。2枚种植体支持的FPD的5年种植体和修复体CSR为97.7%，3枚种植体支持的FPD为97.3%。5年时的平均骨吸收为0.4mm。2枚种植体支持的FPD中，修复体和基台螺钉松动明显更多。论文三。早期负载组种植体的5年CSR为94.4%，修复体为92.5%；延迟负载组分别为97.9%和98.0%。早期组需要更多修复体调整或更换，但早期负载治疗的患者对治疗过程更满意。论文四。5年CSR生存率为99.4%。1例患者的3枚种植体发生骨折。潜入式种植体5年时的平均骨吸收为0.7mm，非潜入式种植体为0.5mm。论文五。所有支架均显示出临床可接受的适配性，所有支架的平均变形值在x轴23微米、y轴26微米、z轴4微米和三维3毫米范围内。对照支架的变形程度高于在严格测试情况下生产的支架。
在部分无牙颌中，全牙弓下颌修复体的支持种植体数量减少至4枚，三单位FPD的支持种植体数量减少至2枚，与使用更多种植体的临床效果相同。无牙下颌的非潜入式种植体植入与潜入式一样可预测，但种植体支持的下颌修复体早期负载会导致更多修复并发症。计算机数控铣削的支架呈现出在临床可接受范围内的适配精度水平，优于早期发表的铸造支架结果。
