Background: A reduced residual dentine thickness following crown preparation has a conceivable impact on pulp degeneration by increasing the pulp’s susceptibility to injury. In crown preparations, three different fin...Background: A reduced residual dentine thickness following crown preparation has a conceivable impact on pulp degeneration by increasing the pulp’s susceptibility to injury. In crown preparations, three different finishing lines are used. These are shoulder, chamfer, and knife edge. Each with its comparative advantages and disadvantages. There is inadequate scientific evidence on which of these finishing lines will leave the most amount of residual dentine, after standard crown preparations on mandibular incisors and maxillary lateral incisors to preserve their pulpal health. Objective: To evaluate residual dentine thickness following various cervical finishing lines of anterior crown preparations for zirconia full coverage. Materials and Methods: A prospective comparative study was conducted from September 2<sup>nd</sup> to November 5<sup>th</sup>, 2022, using mandibular incisors and maxillary laterals extracted from individuals between ages 18 to 30. Each of the three groups of teeth was randomly divided into three cervical margin preparations as follows: Shoulder (n = 15), chamfer (n = 15), and knife edge (n = 15). The teeth were disinfected and stored in 10% formalin. Silicone impressions followed by crown preparations were done on teeth mounted on phantom head manikins. The teeth were sectioned 0.5 mm coronal to the cemento-enamel junction using a separating disc and the mesial, distal, buccal, and lingual thickness were measured using a digital caliper. ANOVA analysis was applied to assess the difference in mean residual dentine thickness among the finishing lines and the Tukey test used for mean comparison. Results: Knife edge finishing lines had 2.05 mm of residual dentine thickness, for upper lateral incisors lingually and had an amount of 1.55 mm and 1.47 mm for lower central teeth mesially and distally respectively. Shoulder finishing lines had an amount of 0.58 mm for lower lateral incisors mesially. Interproximal areas had the least amounts of residual dentine for shoulder and chamfer finishing lines of 0.58 mm and 0.78 mm respectively. Conclusions: There was a significant statistical difference in the thickness of residual dentine at the various cervical finishing line margins. The knife edge finishing line was protective enough for zirconia crown preparations.展开更多
Background: Knife edge, chamfer, and shoulder are the three distinct finishing lines utilized in crown preparations. Each finishing line has relative benefits and drawbacks. However, not much scientific data exists re...Background: Knife edge, chamfer, and shoulder are the three distinct finishing lines utilized in crown preparations. Each finishing line has relative benefits and drawbacks. However, not much scientific data exists regarding which of these finishing lines will leave the most amount of residual dentine coronally on maxillary lateral incisors and mandibular incisors. Objective: To assess the coronal residual dentine thickness after different cervical finishing lines for anterior crown preparations. Materials and Methods: A prospective comparative study was conducted including mandibular incisors and maxillary laterals that were taken from subjects from 18 to 30 years old. Teeth in each of the three groups were randomly separated into three cervical margin preparation groups: knife edge, chamfer and shoulder. The teeth were then prepared for single crown coverage using these finishing lines. The teeth were sectioned halfway through the crown preparation, and a digital caliper was used to determine the residual dentine thickness at the buccal, lingual, mesial and distal areas. The Tukey test was used for mean comparison, and ANOVA analysis was used to evaluate the variation in mean residual dentine thickness. Results: For upper lateral incisors, knife edge finishing lines showed the highest amount of remaining dentine thickness—1.5 mm. lingually, while the upper lateral incisors mesially had the least amount of 0.53 mm for shoulder finishing lines. The least residual dentine (0.53 mm for the shoulder and 0.70 mm for the chamfer finishing line) was found in the interproximal portions of all the teeth that were selected. Lower central incisors had the least amount of residual dentine 0.61 mm for shoulder preparations mesially whiles lower lateral incisors had the least amount of residual dentine for shoulder preparations 0.58 mm distally. There was a statistically significant difference of 0.001 across the groups. Conclusion: The thickness of residual dentine seen coronally after the three finishing line preparations showed a statistically significant difference and the knife edge finishing line provided enough coronal protection within the scope of this study.展开更多
目的:牙本质敏感症(dentin hypersensitivity,DH)作为口腔中常见的一种症状和疾病,可能对患者的生活质量产生较大影响,本研究通过体外实验比较Regesi生物活性材料、Gluma脱敏剂和可乐丽菲露Clearfil SE Bond两步法粘接剂对牙本质小管封...目的:牙本质敏感症(dentin hypersensitivity,DH)作为口腔中常见的一种症状和疾病,可能对患者的生活质量产生较大影响,本研究通过体外实验比较Regesi生物活性材料、Gluma脱敏剂和可乐丽菲露Clearfil SE Bond两步法粘接剂对牙本质小管封闭程度及耐久性的差异,为其用于牙本质敏感症的治疗提供数据支持。方法:体外实验中,用离体牙制作牙本质敏感模型,根据脱敏材料的不同进行随机分组(对照组:人工唾液组;A组:Regesi组;B组:Gluma组;C组:Clearfil SEBond组),通过SEM观察脱敏剂作用后,4组牙本质敏感模型的形貌及牙本质小管封闭效果,分析对比其脱敏效果的差异,并通过耐磨性实验,分析材料间脱敏效果持久性之间的差异及表面硬度的差异。结果:SEM观察可见A、B、C组的牙本质小管封闭效果均优于对照组,结果有统计学差异,其中A组封闭效果最好,较其他两组有统计学差异。耐磨性实验前后,A组的表面硬度均高于其他三组,结果有统计学差异。结论:Regesi生物活性材料较Gluma脱敏剂和Clearfil SE Bond两步法粘接剂对牙本质小管的封闭程度及耐久性能更佳,能更好地治疗牙本质敏感症。展开更多
目的:比较使用不同模式Er:YAG激光以及传统车针去龋后牙本质与复合树脂的粘接强度。方法:选用人类离体磨牙模拟龋坏,分别采用Er:YAG激光中短脉冲(medium short pulse,MSP)模式、Er:YAG激光超短脉冲(super short pulse,SSP)模式和传统车...目的:比较使用不同模式Er:YAG激光以及传统车针去龋后牙本质与复合树脂的粘接强度。方法:选用人类离体磨牙模拟龋坏,分别采用Er:YAG激光中短脉冲(medium short pulse,MSP)模式、Er:YAG激光超短脉冲(super short pulse,SSP)模式和传统车针去除模拟的龋坏后,采用自酸蚀粘接剂将牙体标本与复合树脂粘接制成试件。使用万能试验机对试件进行拉伸试验,测得断裂负荷和粘接强度,并采用单因素方差分析和Tukey多重比较进行统计学分析。采用扫描电子显微镜观察3种不同去龋方式处理后的牙本质表面形态,以及涂布自酸蚀粘接剂并固化后试件的横截面形态。结果:使用Er:YAG激光MSP模式处理后牙本质与复合树脂的粘接强度最高,SSP模式处理后次之,传统车针处理后最低,但差异无统计学意义(P>0.05)。扫描电子显微镜图像显示,Er:YAG激光MSP模式处理后的牙本质表面较平坦,牙本质小管内几乎没有残屑;Er:YAG激光SSP模式处理后的牙本质表面呈现鳞片状,牙本质小管内可见少量碎屑;而传统车针处理后牙本质小管大部分处于被表面牙本质部分甚至完全遮盖的状态,牙本质小管内充满残屑。结论:使用Er:YAG激光去龋相比传统车针去龋可以获得较好的牙本质粘接强度,且对牙本质小管的处理深度和洁净度明显优于传统车针去龋,其中MSP模式更佳。展开更多
目的研究渗透树脂的牙本质小管封闭能力以及牙本质粘接效果。方法选取2021年3月至2022年10月收集的由于正畸需要拔除的健康第三磨牙120颗,随机分为比较组和分析组,每组60颗。比较组选用Single bond Universal(SBU)粘接剂,分析组选取干...目的研究渗透树脂的牙本质小管封闭能力以及牙本质粘接效果。方法选取2021年3月至2022年10月收集的由于正畸需要拔除的健康第三磨牙120颗,随机分为比较组和分析组,每组60颗。比较组选用Single bond Universal(SBU)粘接剂,分析组选取干燥粘接联合渗透树脂,每组每次各选20颗用于封闭牙本质小管实验,微拉伸粘接强度实验,微渗漏实验,比较2组实验情况。结果2组间牙本质小管封闭率、微拉伸粘接强度差异无统计学意义(P>0.05);比较组龈壁微渗漏程度低于分析组,差异有统计学意义(P<0.05)。结论渗透树脂能够对牙本质小管进行有效封闭,并且对于牙本质粘接强度不会产生鲜明影响,但将其用作脱敏剂存在加重微渗漏情况,故应结合实际情况科学选取。展开更多
文摘Background: A reduced residual dentine thickness following crown preparation has a conceivable impact on pulp degeneration by increasing the pulp’s susceptibility to injury. In crown preparations, three different finishing lines are used. These are shoulder, chamfer, and knife edge. Each with its comparative advantages and disadvantages. There is inadequate scientific evidence on which of these finishing lines will leave the most amount of residual dentine, after standard crown preparations on mandibular incisors and maxillary lateral incisors to preserve their pulpal health. Objective: To evaluate residual dentine thickness following various cervical finishing lines of anterior crown preparations for zirconia full coverage. Materials and Methods: A prospective comparative study was conducted from September 2<sup>nd</sup> to November 5<sup>th</sup>, 2022, using mandibular incisors and maxillary laterals extracted from individuals between ages 18 to 30. Each of the three groups of teeth was randomly divided into three cervical margin preparations as follows: Shoulder (n = 15), chamfer (n = 15), and knife edge (n = 15). The teeth were disinfected and stored in 10% formalin. Silicone impressions followed by crown preparations were done on teeth mounted on phantom head manikins. The teeth were sectioned 0.5 mm coronal to the cemento-enamel junction using a separating disc and the mesial, distal, buccal, and lingual thickness were measured using a digital caliper. ANOVA analysis was applied to assess the difference in mean residual dentine thickness among the finishing lines and the Tukey test used for mean comparison. Results: Knife edge finishing lines had 2.05 mm of residual dentine thickness, for upper lateral incisors lingually and had an amount of 1.55 mm and 1.47 mm for lower central teeth mesially and distally respectively. Shoulder finishing lines had an amount of 0.58 mm for lower lateral incisors mesially. Interproximal areas had the least amounts of residual dentine for shoulder and chamfer finishing lines of 0.58 mm and 0.78 mm respectively. Conclusions: There was a significant statistical difference in the thickness of residual dentine at the various cervical finishing line margins. The knife edge finishing line was protective enough for zirconia crown preparations.
文摘Background: Knife edge, chamfer, and shoulder are the three distinct finishing lines utilized in crown preparations. Each finishing line has relative benefits and drawbacks. However, not much scientific data exists regarding which of these finishing lines will leave the most amount of residual dentine coronally on maxillary lateral incisors and mandibular incisors. Objective: To assess the coronal residual dentine thickness after different cervical finishing lines for anterior crown preparations. Materials and Methods: A prospective comparative study was conducted including mandibular incisors and maxillary laterals that were taken from subjects from 18 to 30 years old. Teeth in each of the three groups were randomly separated into three cervical margin preparation groups: knife edge, chamfer and shoulder. The teeth were then prepared for single crown coverage using these finishing lines. The teeth were sectioned halfway through the crown preparation, and a digital caliper was used to determine the residual dentine thickness at the buccal, lingual, mesial and distal areas. The Tukey test was used for mean comparison, and ANOVA analysis was used to evaluate the variation in mean residual dentine thickness. Results: For upper lateral incisors, knife edge finishing lines showed the highest amount of remaining dentine thickness—1.5 mm. lingually, while the upper lateral incisors mesially had the least amount of 0.53 mm for shoulder finishing lines. The least residual dentine (0.53 mm for the shoulder and 0.70 mm for the chamfer finishing line) was found in the interproximal portions of all the teeth that were selected. Lower central incisors had the least amount of residual dentine 0.61 mm for shoulder preparations mesially whiles lower lateral incisors had the least amount of residual dentine for shoulder preparations 0.58 mm distally. There was a statistically significant difference of 0.001 across the groups. Conclusion: The thickness of residual dentine seen coronally after the three finishing line preparations showed a statistically significant difference and the knife edge finishing line provided enough coronal protection within the scope of this study.
文摘目的:牙本质敏感症(dentin hypersensitivity,DH)作为口腔中常见的一种症状和疾病,可能对患者的生活质量产生较大影响,本研究通过体外实验比较Regesi生物活性材料、Gluma脱敏剂和可乐丽菲露Clearfil SE Bond两步法粘接剂对牙本质小管封闭程度及耐久性的差异,为其用于牙本质敏感症的治疗提供数据支持。方法:体外实验中,用离体牙制作牙本质敏感模型,根据脱敏材料的不同进行随机分组(对照组:人工唾液组;A组:Regesi组;B组:Gluma组;C组:Clearfil SEBond组),通过SEM观察脱敏剂作用后,4组牙本质敏感模型的形貌及牙本质小管封闭效果,分析对比其脱敏效果的差异,并通过耐磨性实验,分析材料间脱敏效果持久性之间的差异及表面硬度的差异。结果:SEM观察可见A、B、C组的牙本质小管封闭效果均优于对照组,结果有统计学差异,其中A组封闭效果最好,较其他两组有统计学差异。耐磨性实验前后,A组的表面硬度均高于其他三组,结果有统计学差异。结论:Regesi生物活性材料较Gluma脱敏剂和Clearfil SE Bond两步法粘接剂对牙本质小管的封闭程度及耐久性能更佳,能更好地治疗牙本质敏感症。
文摘目的:比较使用不同模式Er:YAG激光以及传统车针去龋后牙本质与复合树脂的粘接强度。方法:选用人类离体磨牙模拟龋坏,分别采用Er:YAG激光中短脉冲(medium short pulse,MSP)模式、Er:YAG激光超短脉冲(super short pulse,SSP)模式和传统车针去除模拟的龋坏后,采用自酸蚀粘接剂将牙体标本与复合树脂粘接制成试件。使用万能试验机对试件进行拉伸试验,测得断裂负荷和粘接强度,并采用单因素方差分析和Tukey多重比较进行统计学分析。采用扫描电子显微镜观察3种不同去龋方式处理后的牙本质表面形态,以及涂布自酸蚀粘接剂并固化后试件的横截面形态。结果:使用Er:YAG激光MSP模式处理后牙本质与复合树脂的粘接强度最高,SSP模式处理后次之,传统车针处理后最低,但差异无统计学意义(P>0.05)。扫描电子显微镜图像显示,Er:YAG激光MSP模式处理后的牙本质表面较平坦,牙本质小管内几乎没有残屑;Er:YAG激光SSP模式处理后的牙本质表面呈现鳞片状,牙本质小管内可见少量碎屑;而传统车针处理后牙本质小管大部分处于被表面牙本质部分甚至完全遮盖的状态,牙本质小管内充满残屑。结论:使用Er:YAG激光去龋相比传统车针去龋可以获得较好的牙本质粘接强度,且对牙本质小管的处理深度和洁净度明显优于传统车针去龋,其中MSP模式更佳。
文摘目的研究渗透树脂的牙本质小管封闭能力以及牙本质粘接效果。方法选取2021年3月至2022年10月收集的由于正畸需要拔除的健康第三磨牙120颗,随机分为比较组和分析组,每组60颗。比较组选用Single bond Universal(SBU)粘接剂,分析组选取干燥粘接联合渗透树脂,每组每次各选20颗用于封闭牙本质小管实验,微拉伸粘接强度实验,微渗漏实验,比较2组实验情况。结果2组间牙本质小管封闭率、微拉伸粘接强度差异无统计学意义(P>0.05);比较组龈壁微渗漏程度低于分析组,差异有统计学意义(P<0.05)。结论渗透树脂能够对牙本质小管进行有效封闭,并且对于牙本质粘接强度不会产生鲜明影响,但将其用作脱敏剂存在加重微渗漏情况,故应结合实际情况科学选取。
