Piemjai M, Nakabayashi N
Department of Prosthodontics, Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand.
J Adhes Dent. 2001 Winter;3(4):325-31.
By altering either ferric chloride concentration in 10% citric acid (1% ferric chloride = 10-1; 5% ferric chloride = 10-5; 10% ferric chloride = 10-10) or conditioning periods with an aqueous mixture of 1% citric acid and 1% ferric chloride (1-1), the influence of dentin substrate on bond strength and hybridized dentin in wet bonding of 4-META/MMA-TBB resin was examined.
Dentin surfaces of fresh bovine incisors were conditioned either with 10-1, 10-5, or 10-10 mixtures for 10 s (10-1-10s, 10-5-10s, 10-10-10s groups) or with a 1-1 mixture for 5, 10, 30 or 60 s (1-1-5s, 1-1-10s, 1-1-30s, 1-1-60s groups). Rinsed, demineralized dentin samples were kept wet, primed with 5% 4-META in acetone for 60 s, and bonded with 4-META/MMA-TBB resin. Bonded specimens were trimmed to a mini-dumbbell shape for tensile testing. The cross sections of bonded specimens were modified with HCl and NaOCl in order to assess the hybrid layer. The fractured surfaces of specimens and the hybridized dentin were investigated with SEM.
No significant difference (p > 0.01) in tensile strength was identified between 10-1-10s and 10-5-10s groups (30 MPa), 10-10-10s and 1-1-5s groups (15 MPa), and the three groups conditioned by 1-1-10s, -30s and -60s (40 MPa). The thickness of the hybrid layer increased with increasing either ferric chloride or conditioning periods.
The concentration of ferric chloride in 10% citric acid for wet bonding must be less than 5% in order to provide a reliable bond. When applied from 10 to 60 s, the 1-1 conditioner provided hybridized dentin with reliable tensile bond strength. The thickness of the hybrid layer did not influence the tensile bond strength.
通过改变10%柠檬酸中氯化铁的浓度（1%氯化铁=10⁻¹；5%氯化铁=10⁻⁵；10%氯化铁=10⁻¹⁰）或用1%柠檬酸和1%氯化铁的水性混合物（1-1）进行预处理的时间，研究牙本质基质对4-META/MMA-TBB树脂湿粘结中粘结强度和杂交牙本质的影响。
新鲜牛切牙的牙本质表面分别用10⁻¹、10⁻⁵或10⁻¹⁰混合物处理10秒（10⁻¹-10s、10⁻⁵-10s、10⁻¹⁰-10s组），或用1-1混合物处理5、10、30或60秒（1-1-5s、1-1-10s、1-1-30s、1-1-60s组）。冲洗、脱矿后的牙本质样本保持湿润，用5%的4-META丙酮溶液处理60秒，然后用4-META/MMA-TBB树脂粘结。将粘结后的标本修整成微型哑铃状进行拉伸测试。用盐酸和次氯酸钠处理粘结标本的横截面，以评估混合层。用扫描电子显微镜研究标本的断裂表面和杂交牙本质。
10⁻¹-10s组和10⁻⁵-10s组（30MPa）、10⁻¹⁰-10s组和1-1-5s组（15MPa）以及用1-1-10s、-30s和-60s处理的三组（40MPa）之间的拉伸强度无显著差异（p>0.01）。混合层的厚度随着氯化铁浓度或预处理时间的增加而增加。
为了获得可靠的粘结，10%柠檬酸中用于湿粘结的氯化铁浓度必须小于5%。当处理时间为10至60秒时，1-1处理剂能为杂交牙本质提供可靠的拉伸粘结强度。混合层的厚度不影响拉伸粘结强度。
