27例磁性附着体固位种植覆盖义齿临床体会

目的：评价磁性附着体固位种植覆盖义齿在牙槽骨严重吸收的无牙颌患者中运用的临床效果。方法：27例牙槽骨严重吸收的无牙颌患者,植入2—4枚牙种植体,3-6个月后进行种植体支持式磁性附着体固位覆盖义齿修复,定期复查,随访8—79个月。采用临床检查、x线检查和患者主观感受问卷来评价此类义齿的修复效果。结果：27例患者61枚种植体,1枚在修复前由于种植体周围炎松动被拔除,3枚在覆盖义齿修复后发生种植体周围炎松动被拔除,其余种植体均稳固无松动;27件种植覆盖义齿的固位、稳定、咀嚼功能均良好,患者满意度高。结论：运用磁性附着体固位种植覆盖义齿修复牙槽骨严重吸收的无牙颌能很好的恢复咀嚼功能,且制作方法简单,值得临床大力推广。     

无牙颌种植修复设计

牙列缺失后,常存在颌位关系异常,同时口腔黏膜组织萎缩变薄,敏感度增加,义齿难以获得良好的固位及咀嚼功能。种植修复能够降低骨吸收量,增加义齿稳定性,减少戴牙后疼痛,是恢复患者咀嚼功能的有效方法。但患者个体差异导致的咬合力大小,颌间距离,牙槽骨高度、宽度及质量,黏膜厚度等条件均有差异,不同医师提出的治疗方案各异,难以统一。本文拟就无牙颌种植修复常见问题及设计时应考虑的因素作以讨论。     

Masticatory function and bite force of mandibular single-implant overdentures and complete dentures: a randomized crossover control study

PurposeThe study aimed to compare the mixing ability (MA), comminuting ability (CA), and maximum bite force (MBF) of single-implant overdentures (IODs) and clinically acceptable complete dentures (CDs) through a randomized crossover control trial.MethodsNew CDs were fabricated for 22 patients. One implant was inserted in the middle of the symphyseal region for each patient. The patients were randomly allocated into two groups: group IC received an IOD, whereas group CI received a CD, for 2 months; the treatments were interchanged for the next 2 months. The MA, CA, and MBF were evaluated with the old CDs, new CDs (at the end of CD treatment period), and IODs (at the end of IOD treatment period).ResultsThe MA, CA, and MBF of the IODs were significantly higher than those of the old and new CDs (p < 0.01). New CDs only showed a significant improvement in MA (p < 0.05), while there were no significant differences in CA and MBF between the old and new CDs.ConclusionsCompared with the CD, IOD is more effective in restoring the MA, CA, and MBF of edentulous mandibles.     

Reconstruction of the extremely atrophied mandible with iliac crest onlay grafts followed by two endosteal implants: a retrospective study with long-term follow-up

Treatment outcomes of implant-retained lower dentures on two endosseous implants placed in severely atrophied mandibles after reconstruction with iliac crest onlay grafts were assessed in a retrospective observational study. All consecutive patients treated between 2000 and 2007 were recalled in 2012 (n = 40). Survival of the implants, the condition of hard and soft peri-implant tissues, and patient satisfaction were scored. One implant was lost after 5.5 years. The mean mandibular symphysis height was 8.9 ± 2.2, 16.4 ± 2.7, 15.7 ± 2.7, and 15.4 ± 2.5 mm at intake, after augmentation, after implantation, and at the last recall visit, respectively. Mean radiographic peri-implant bone loss was 0.6 ± 0.7 mm. Mean clinical index scores were very low. Patient satisfaction was high. Surgical complications related to the donor site were seroma (n = 1), haematoma (n = 2), and sensory disturbance of the lateral femoral cutaneous nerve (n = 1); all had resolved before placement of the implants. Eleven patients reported postsurgical sensory disturbances of the mental nerve, of whom five still experienced some sensory disturbance at the last recall visit. Augmentation of the extremely resorbed mandible with an iliac crest onlay graft followed by placement of two implants 4 months later provides a solid basis for a bar-retained overdenture with favourable clinical and radiographic results.     

Replacement of a mandibular implant-fixed prosthesis with an implant-supported overdenture to improve maintenance and care

PatientsA 69-year-old woman presented to the Osaka University Dental Hospital. She had two chief complaints, (a) food accumulation under the lower teeth and (b) poor maxillary denture retention while eating. On clinical examination the patient presented with a maxillary complete denture and fixed mandibular implant prosthesis. For preventing food accumulation under the fixed implant prosthesis and to keep the maxillary denture stable by providing posterior occlusal contact for bilaterally balanced occlusion, the use of a mandibular implant-supported overdenture with self-adjusting magnetic attachments provided a prosthetic solution for this patient. After provided the new dentures, the patient was pleased and was comfortable with the aesthetic, stability and retention of the dentures. There were no discernable clinical or radiographic changes after 1 year of use.DiscussionTo prevent food accumulation beneath the fixed implant prosthesis and maintain the stability of the maxillary denture by providing posterior occlusal contact for bilaterally balanced occlusion, a mandibular implant-retained overdenture with magnetic attachments was used to provide a prosthetic solution for this patient.ConclusionIn this clinical case, an implant-fixed prosthesis in the edentulous mandibular region was replaced into an implant-supported overdenture with considerations for (a) preventing the food accumulation beneath the lower prosthesis, (b) achieving the proper occlusion in the posterior part for maxillary denture stability and (c) ease of maintenance and care for the prostheses.     

Attachment systems for implant overdenture: influence of implant inclination on retentive and lateral forces

Objective: To evaluate the retentive force and lateral force of an implant with various types of attachments for overdentures in relation to implant inclination. Material and methods: An implant (3.75 × 13 mm) was embedded into an acrylic resin block, simulating the edentulous ridge. Four different attachment systems were used, including: (1) Locator black and blue, (2) a ball attachment, (3) a flat‐type magnetic attachment and (4) a self‐adjusting magnetic attachment, which has vertical and rotational movement. All of the attachments were under a constant dislodging force with an angle of the implant at 0°, 15°, 30° and 45°, and the experiments were repeated 10 times using a universal testing machine to measure the retentive force. The lateral force to the implant was measured by strain gauges attached on the implant surface. Statistical analysis was performed by multiple comparisons with Bonferroni's correction. P<0.05 was considered statistically significant. Results: At 0°, the significantly highest retentive force was observed in the Locator blue, followed by the Locator black, ball, flat‐type and self‐adjusting magnetic attachments. The Locator blue and ball attachment maintained the retentive force until a 30° inclination; however, the lateral force increased significantly, especially with the ball attachment. The retentive force of the magnetic attachment was significantly lower at 0°, as well as the lateral force in the self‐adjusting magnetic attachment. Conclusion: Within the limitations of this study, we conclude that the retentive force decreases with an increase in implant inclination, whereas the lateral force increases, except for in magnetic attachments. To cite this article:
Yang T‐C, Maeda Y, Gonda T, Kotecha S. Attachment systems for implant overdenture: influence of implant inclination on retentive and lateral forces.
Clin. Oral Impl. Res. 22 , 2011; 1315–1319.
doi: 10.1111/j.1600‐0501.2010.02137.x     

种植体支持球帽附着体固位下颌覆盖全口义齿的临床应用

目的:评价种植体支持球帽附着体固位的下颌覆盖全口义齿临床应用效果.方法:随机选择15例下颌无牙颌患者,每例植入2枚种植体,共植入30枚,随访观察1-12个月,从患者满意度、临床检查及种植体X线片观察修复效果.结果:种植体支持覆盖全口义齿修复下颌无牙颌,义齿固位和咀嚼功能满意率分别为100％和93.3％,义齿稳固,咀嚼功...