Background: The accuracy of the final prosthesis is affected by the final impression technique and master cast production. The aim of the present study was to evaluate the effect of the functional impression technique...Background: The accuracy of the final prosthesis is affected by the final impression technique and master cast production. The aim of the present study was to evaluate the effect of the functional impression technique with various impression materials on the surface characteristic of dental stone casts and their clinical effect on the retention of complete dentures. Method: Specimens of three impression materials/stone casts were fabricated. The specimens of the impression materials/stone casts were divided into three equal groups (I, II, and III). The impression materials used were as follows: tissue conditioner group (I), zinc oxide (ZEO) (group II) and poly (vinyl siloxane) (PVS) (group III). Cylindrical split aluminium moulds were designed to receive the impression materials and the stone mixture. The surface roughness of the stone cast specimens of the three groups (I, II, and III) was measured with a surface profilometer and analyzed by a scanning electron microscope. A clinical study included five severely resorbed mandibular edentulous alveolar ridges and edentulous maxillary arches. Each subject received three heat-cured acrylic resin dentures, fabricated using the functional impression technique. The three dentures were identical except for the different impression materials used from Groups I, II and III. The retentive force of each denture for each subject was measured. Result: The results of this study revealed that the mean value of surface roughness of the stone cast surface of group I was higher than group II and group III. A statistically significant difference was observed in surface roughness and the retentive dislodging force between the three studied groups. Although using a tissue conditioner as a functional impression material led to a high level of surface roughness and good retention, it could not produce the same smooth surface quality of PVS or ZEO. These data were supported by SEM analysis. The complete dentures for these patients require important oral and denture hygiene care. Conclusion: Complete dentures made using functional impression technique with PVC as a final impression material are more comfortable, retentive and stable.展开更多
目的探讨修正模型印模技术对肯氏Ⅰ、Ⅱ类牙列缺损模型游离端牙槽嵴形态及可摘局部义齿(RPD)修复效果的影响。方法选择54例下颌肯氏Ⅰ、Ⅱ类牙列缺损患者。采用修正模型印模法及常规印模法分别为同一患者取模;将模型游离端由远中至近中...目的探讨修正模型印模技术对肯氏Ⅰ、Ⅱ类牙列缺损模型游离端牙槽嵴形态及可摘局部义齿(RPD)修复效果的影响。方法选择54例下颌肯氏Ⅰ、Ⅱ类牙列缺损患者。采用修正模型印模法及常规印模法分别为同一患者取模;将模型游离端由远中至近中逐层进行冠状横截面扫描;比较图像形态差异,并分析该差异与横截面位置之间的关系。将患者按配对设计均分为2组,分别采用修正模型印模技术和常规印模技术取模制作RPD;比较2组患者适应期的调改次数、适应期结束后义齿咀嚼是否有力、咀嚼时游离端基托是否存在肉眼可见动度。结果修正模型印模法及常规印模法所获模型同一横截面图像像素数差异有统计学意义(P<0.01),前者小于后者;像素数差值D与切磨次数N(横截面位置)之间呈负相关;修正模型组适应期调改次数(次:1.12±0.77 vs 3.41±0.82)、游离端基托存在肉眼可见动度阳性率低于常规模型组(0 vs 18.5%),调改后义齿咀嚼有力阳性率高于常规模型组(96.3%vs74.1%)。结论采用修正模型印模技术所获模型的游离端牙槽嵴形态与常规印模法所获模型有明显差异,距末端基牙远中面越远差异越大;采用该技术取模制作的RPD修复效果优于采用常规印模技术制作者。展开更多
目的:探讨改良式硅橡胶印模定位平行投照技术的临床运用。方法:选取24例牙周炎牙周治疗患者及 24例牙体牙髓科根管治疗的患者,分别进行硅橡胶印模定位平行投照和分角线投照,分别测量数字式根尖片上沿牙长轴方向的牙体长度(L)及釉牙骨质...目的:探讨改良式硅橡胶印模定位平行投照技术的临床运用。方法:选取24例牙周炎牙周治疗患者及 24例牙体牙髓科根管治疗的患者,分别进行硅橡胶印模定位平行投照和分角线投照,分别测量数字式根尖片上沿牙长轴方向的牙体长度(L)及釉牙骨质界牙体宽度(W),按照牙位分为前牙+上颌磨牙组和下颌磨牙组,使用SPSS 22.0软件进行配对 t 检验及相关性分析比较2种投照技术2次投照的差异。结果:虽然两种投照技术前后2次投照的牙体长度及宽度的配对 t 检验均不具有显著性差异( P >0.05),但是与分角线投照技术相比,改良式硅橡胶印模定位平行投照技术所得到的前后两次根尖片上的牙体长度和宽度的组内相关系数更高。结论:改良式硅橡胶印模定位投照技术是一种稳定可靠、可操作性强的根尖片投照技术,适用于需要进行纵向定量对比的各类口腔科疾病诊断和分析。展开更多
文摘Background: The accuracy of the final prosthesis is affected by the final impression technique and master cast production. The aim of the present study was to evaluate the effect of the functional impression technique with various impression materials on the surface characteristic of dental stone casts and their clinical effect on the retention of complete dentures. Method: Specimens of three impression materials/stone casts were fabricated. The specimens of the impression materials/stone casts were divided into three equal groups (I, II, and III). The impression materials used were as follows: tissue conditioner group (I), zinc oxide (ZEO) (group II) and poly (vinyl siloxane) (PVS) (group III). Cylindrical split aluminium moulds were designed to receive the impression materials and the stone mixture. The surface roughness of the stone cast specimens of the three groups (I, II, and III) was measured with a surface profilometer and analyzed by a scanning electron microscope. A clinical study included five severely resorbed mandibular edentulous alveolar ridges and edentulous maxillary arches. Each subject received three heat-cured acrylic resin dentures, fabricated using the functional impression technique. The three dentures were identical except for the different impression materials used from Groups I, II and III. The retentive force of each denture for each subject was measured. Result: The results of this study revealed that the mean value of surface roughness of the stone cast surface of group I was higher than group II and group III. A statistically significant difference was observed in surface roughness and the retentive dislodging force between the three studied groups. Although using a tissue conditioner as a functional impression material led to a high level of surface roughness and good retention, it could not produce the same smooth surface quality of PVS or ZEO. These data were supported by SEM analysis. The complete dentures for these patients require important oral and denture hygiene care. Conclusion: Complete dentures made using functional impression technique with PVC as a final impression material are more comfortable, retentive and stable.
文摘目的探讨修正模型印模技术对肯氏Ⅰ、Ⅱ类牙列缺损模型游离端牙槽嵴形态及可摘局部义齿(RPD)修复效果的影响。方法选择54例下颌肯氏Ⅰ、Ⅱ类牙列缺损患者。采用修正模型印模法及常规印模法分别为同一患者取模;将模型游离端由远中至近中逐层进行冠状横截面扫描;比较图像形态差异,并分析该差异与横截面位置之间的关系。将患者按配对设计均分为2组,分别采用修正模型印模技术和常规印模技术取模制作RPD;比较2组患者适应期的调改次数、适应期结束后义齿咀嚼是否有力、咀嚼时游离端基托是否存在肉眼可见动度。结果修正模型印模法及常规印模法所获模型同一横截面图像像素数差异有统计学意义(P<0.01),前者小于后者;像素数差值D与切磨次数N(横截面位置)之间呈负相关;修正模型组适应期调改次数(次:1.12±0.77 vs 3.41±0.82)、游离端基托存在肉眼可见动度阳性率低于常规模型组(0 vs 18.5%),调改后义齿咀嚼有力阳性率高于常规模型组(96.3%vs74.1%)。结论采用修正模型印模技术所获模型的游离端牙槽嵴形态与常规印模法所获模型有明显差异,距末端基牙远中面越远差异越大;采用该技术取模制作的RPD修复效果优于采用常规印模技术制作者。
文摘目的:探讨改良式硅橡胶印模定位平行投照技术的临床运用。方法:选取24例牙周炎牙周治疗患者及 24例牙体牙髓科根管治疗的患者,分别进行硅橡胶印模定位平行投照和分角线投照,分别测量数字式根尖片上沿牙长轴方向的牙体长度(L)及釉牙骨质界牙体宽度(W),按照牙位分为前牙+上颌磨牙组和下颌磨牙组,使用SPSS 22.0软件进行配对 t 检验及相关性分析比较2种投照技术2次投照的差异。结果:虽然两种投照技术前后2次投照的牙体长度及宽度的配对 t 检验均不具有显著性差异( P >0.05),但是与分角线投照技术相比,改良式硅橡胶印模定位平行投照技术所得到的前后两次根尖片上的牙体长度和宽度的组内相关系数更高。结论:改良式硅橡胶印模定位投照技术是一种稳定可靠、可操作性强的根尖片投照技术,适用于需要进行纵向定量对比的各类口腔科疾病诊断和分析。
