Lenzi Tathiane Larissa, Bonifácio Clarissa Calil, Bönecker Marcelo, Amerongen W Evert van, Nogueira Fernando Neves, Raggio Daniela Prócida
Department of Orthodontics and Pediatric Dentistry, School of Dentistry, University of São Paulo, Brazil.
J Dent Child (Chic). 2013 Jan-Apr;80(1):20-4.
The purpose of this study was to evaluate the effect of a flowable glass ionomer cement (GIC) layer application on bond strength to sound (SD) and carious primary dentin (CD).
Flat dentin surfaces from primary molars were randomly assigned to 4 groups (N=5) according to substrate (SD or CD; pH-cycling for 14 days); and layers of GIC (1 layer/control [regular powder/liquid ratio] or 2 layers [first a flowable GIC layer and second a regular powder/liquid ratio layer of GIC]). After 24 hours of water storage, specimens were prepared to be evaluated with the microtensile test (1 mm/min). The fracture pattern was evaluated at 400X magnification (stereomicroscope).
The bond strength to SD was higher than to CD when GIC was inserted in 2 layers (P=.02). No significant difference was observed between 1 or 2 layers of GIC insertion (P>.05). For all groups, adhesive/mixed fracture prevailed.
The effect of applying the flowable GIC layer on bond strength to dentin is dependent on substrate and results in an increase in adhesion for sound primary dentin.
本研究旨在评估可流动玻璃离子水门汀（GIC）层的应用对与健康（SD）和龋坏乳牙本质（CD）的粘结强度的影响。
根据底物（SD或CD；pH循环14天），将乳牙的平坦牙本质表面随机分为4组（N = 5）；以及GIC层（1层/对照组[常规粉液比]或2层[第一层为可流动GIC层，第二层为常规粉液比的GIC层]）。储水24小时后，制备标本以用微拉伸试验（1毫米/分钟）进行评估。在400倍放大倍数下（体视显微镜）评估断裂模式。
当插入2层GIC时，与SD的粘结强度高于与CD的粘结强度（P = 0.02）。在插入1层或2层GIC之间未观察到显著差异（P>0.05）。对于所有组，粘结剂/混合断裂占主导。
可流动GIC层对牙本质粘结强度的影响取决于底物，并导致健康乳牙本质的粘结力增加。
