A study of the cavity design in restoration with adhesive composite resin in primary molars

目得：在我们1998年至1999年的研究中，尝试建立空腔的轮廓形状，最大限度地减少边缘的微渗漏，不留下未聚合的树脂，将切割量保持在最低限度，并决定适合制备这种空腔的棒的种类。在有关的一年中，由于上述试棒已经制成，我们在幼年狗中进行了洞制备，并比较了用传统棒和试棒制备的洞对牙髓组织的影响。材料与方法：9只2月龄杂种犬。在戊巴比妥腹腔内麻醉下，使用试棒在右下第三磨牙中制备约0.5 mm深的牙洞，而在左牙中，用FG 301钻石吧形成牙洞。接下来，在这些空腔的底部放置塞子，并填充高粘结碳水泥<TM>以覆盖它。 ...更多信息 制备窝洞后，拔除下颌骨，固定后用Plank-Rychlo溶液脱钙。然后，将标本脱水，石蜡包埋，切成30 μ m厚的切片，并用苏木精和伊红染色。观察牙髓组织的变化。结果和讨论：在洞制备后3天，在对照组和实验组中均观察到毛细血管扩张和洞附近成牙本质细胞的消失或空泡变性。这些变化在对照组中更为显著。第14天，虽然成牙本质细胞的空泡变性不再观察到，显着的炎性细胞浸润和毛细血管扩张显示在邻近的洞底牙髓组织。这些变化在对照组中也表达得更强烈。在第28天，这些炎症体征仅在对照组中持续存在。根据目前的结果，可以得出结论，这种实验测试的粘合剂复合树脂棒适用于临床使用。少

PURPOSE : In our studies from 1998 to 1999, an attempt to establish the outline form of the cavity was made minimizing microleakage from the margin, without unpolymerized resin leaving behind, keeping the cutting to a minimum amount, and to decide the kind of bar adequate to prepare such a cavity. During the concerned year, since the trial bar as above mentioned had already been made, we performed the cavity preparation in infantile dogs and compared the effects on the pulpal tissues between those prepared with a conventional bar and with the trial bar. MATERIAL AND METHODS : Nine 2-month-old mongrel dogswere used. Under intra-abdominal anesthesia with pentobarbital, tooth cavities of approximately 0.5 mm depth were prepared in the right lower third molars using the trial bar, whereas in the left teeth the cavities were formed with a FG301 diamond bar. Next, a stopping was placed in the floor of these cavities and High-bond Carbo-cement ^<TM> was filled to cover it. At 3, 14 and 28 day … More s after the cavity preparation, mandibles were extirpated and decalcified with Plank-Rychlo solution following fixation. Then, the specimens were dehydrated, embedded in paraffin, cut into 30 μm-thick sections and stained with hematoxylin and eosin. Observation was made on the pulpal tissue changes. RESULTS AND DISCUSSION : At 3 days after the cavity preparation, dilatation of the blood capillaries and disappearance or vacuolar degeneration of the odontoblasts in the proximity of the cavities were observed in both the control and experimental groups. These changes were more significant in the control group. At 14 days, although the vacuolar degeneration of odontoblasts was no more observed, marked inflammatory cell infiltration and capillary dilatation were revealed in the pulpal tissue adjacent to the cavity floor. These changes were also more intensely expressed in the control group. At 28 days, these inflammatory signs still persisted only in the control group. Base on the present results, it is concluded that this experimentally tested bar for the adhesive composite resin is applicable to the clinical usage. Less