Dunne S, Millar B
Department of Conservative Dentistry, King's Dental Institute, London.
Prim Dent Care. 1998 Jan;5(1):29-31.
The Universal Dental Anchorage (UDA) System incorporates the use of pins inserted into enamel and dentine to retain a pontic. The pins are placed horizontally into teeth in the region of the contact area and so are potentially placed close to the dental pulp. This study aims to investigate and measure this relationship to assess if the pulp may be placed at risk during pin hole preparation or UDA pin placement.
Teeth were assessed radiographically and pins placed according to manufacturer's instructions. The teeth were subsequently sectioned through the pin position and measurements from the pin tip to the pulp chamber made at 4X magnification.
In the majority of the teeth the pins were in close proximity to the pulp chamber (mean +/- sd = 0.8 +/- 0.7 mm). Two pins were in direct communication with the pulp chamber. Seven pins were separated from the pulp chamber by only 0.1-0.5 mm and six pins by 0.6-1.0 mm. Three pins were more than 1.0 mm from the pulp chamber.
The results suggest that the use of 2.1 mm UDA pins would, in many cases, represent a risk to pulpal health.
通用牙支抗（UDA）系统采用插入牙釉质和牙本质的销钉来固定桥体。销钉水平放置在接触区的牙齿中，因此可能靠近牙髓。本研究旨在调查和测量这种关系，以评估在制备销钉孔或放置UDA销钉时牙髓是否会处于危险之中。
对牙齿进行影像学评估，并按照制造商的说明放置销钉。随后将牙齿沿销钉位置切开，在4倍放大率下测量从销钉尖端到牙髓腔的距离。
在大多数牙齿中，销钉靠近牙髓腔（平均值±标准差=0.8±0.7毫米）。两根销钉与牙髓腔直接相通。七根销钉与牙髓腔仅相隔0.1 - 0.5毫米，六根销钉相隔0.6 - 1.0毫米。三根销钉与牙髓腔的距离超过1.0毫米。
结果表明，在许多情况下，使用2.1毫米的UDA销钉可能会对牙髓健康构成风险。
