Iwamoto Claudio E, Adachi Erika, Pameijer Cornelis H, Barnes Douglas, Romberg Elaine E, Jefferies Steven
Department of Advanced Education in General Dentistry, Baltimore College of Dental Surgery, University of Maryland, USA.
Am J Dent. 2006 Apr;19(2):85-90.
To evaluate the clinical, radiographical and histological findings in human third molars in which mechanical pulp exposures were capped with white ProRoot mineral trioxide aggregate (WMTA).
Forty-eight human third molars, caries-free or with incipient caries, scheduled to be extracted, were used and randomly divided into two groups: Group A: (n= 24) received WMTA and control Group B: (n= 24) received chemical set calcium hydroxide (Dycal). The teeth were isolated with rubber dam and Class I cavities prepared. Pulp exposure was performed using a sterile diamond bur and confirmed by frank bleeding. A sterile cotton pellet dipped in saline solution was placed over the exposure for 60 seconds. The preparation was then lightly rinsed with water and gently air-dried. WMTA or CH was placed over the exposure site followed by a small amount of a light-cured compomer. After etching with 35% phosphoric acid gel for 15 seconds, rinsing and blot drying, Prime and Bond NT adhesive was applied and light-cured. The cavity was then restored with a resin composite and light-cured. Evaluations were performed by phone after 7 days and clinically at 30 +/- 5 and 136 +/- 24 days, using standardized tests and radiographs. The teeth were extracted after 136 +/- 24 days; the roots were cut +/- 4-5 mm from the apex to allow for rapid fixation in 10% neutral buffered formalin. They were then processed for routine histological evaluation, embedded in paraffin, sectioned and stained with hematoxylin and eosin and Brown and Brenn for recognition of bacteria. Statistical analyses were performed using a Mann-Whitney U-test, a Chi-square test, a Fisher's exact test and an ANOVA.
No significant differences in post-operative sensitivity were reported after 7 days between the two materials (P> 0.05). Clinical examination demonstrated no significant differences at 30 +/- 5 days (P> 0.05) and at 136 +/- 24 days (P> 0.05). Histological findings: 45 of 48 teeth were suitable for microscopic evaluation (22 with WMTA and 23 with CH). Twenty from the WMTA and 18 from the CH group had developed a bridge. No statistically significant differences were found for superficial and deep inflammatory cell response (P> 0.05), presence of a dentin bridge (P> 0.01), and pulp vitality (P> 0.01), between WMTA and calcium hydroxide. A statistically significant difference was found for the diameter of exposure (P< or = 0.05) between WMTA (x= 0.35 +/- 0.19 mm) and CH (x= 0.25 +/- 0.09 mm). Only a minimal association between clinical and histological findings could be established for either material.
评估采用白色ProRoot三氧化矿物凝聚体（WMTA）覆盖机械性露髓的人类第三磨牙的临床、影像学和组织学表现。
选取48颗计划拔除的无龋或有早期龋的人类第三磨牙，随机分为两组：A组（n = 24）采用WMTA，对照组B组（n = 24）采用化学固化氢氧化钙（Dycal）。用橡皮障隔离患牙并制备I类洞。使用无菌金刚砂车针进行露髓操作，并通过明显出血确认。将浸有盐溶液的无菌棉球置于露髓处60秒。然后用清水轻轻冲洗并轻轻吹干制备洞型。将WMTA或CH置于露髓部位，随后放置少量光固化复合树脂。用35%磷酸凝胶酸蚀15秒，冲洗并吸干，涂布Prime and Bond NT粘结剂并光固化。然后用树脂复合材料修复窝洞并光固化。在7天后通过电话进行评估，并在30±5天和136±24天进行临床评估，采用标准化测试和X线片。在136±24天后拔除牙齿；从根尖处切断牙根±4 - 5毫米，以便快速固定于10%中性缓冲福尔马林中。然后进行常规组织学评估，石蜡包埋，切片，并用苏木精和伊红以及Brown和Brenn染色以识别细菌。采用Mann - Whitney U检验、卡方检验、Fisher精确检验和方差分析进行统计分析。
两种材料在7天后报告的术后敏感性无显著差异（P>0.05）。临床检查显示在30±5天（P>0.05）和136±24天（P>0.05）均无显著差异。组织学结果：48颗牙齿中有45颗适合显微镜评估（22颗采用WMTA，23颗采用CH）。WMTA组20颗和CH组18颗形成了牙本质桥。在WMTA和氢氧化钙之间，浅表和深部炎症细胞反应（P>0.05）、牙本质桥的存在（P>0.01）以及牙髓活力（P>0.01）均未发现统计学显著差异。在WMTA（x = 0.35±0.19毫米）和CH（x = 0.25±0.09毫米）之间发现露髓直径存在统计学显著差异（P≤0.05）。两种材料的临床和组织学表现之间仅建立了最小的关联。
