우(牛)하악골의 천공시 발생하는 마찰열에 관한 실험적 연구

Abstract

[한글]

구강 및 악안면 외과 영역에서 bur를 사용하여 피질골, 망상골 천공과 제거를 많이 시행한다. bur를 사용할 때는 마찰열이 발생하는데 56℃ 이상이 되면 비가역적 골 괴사 증상이 일어난다고 알려져 있다.

이러한 골의 삭제, 천공 때에 발생하는 마찰열을 감소시키기 위하여 저회전 속도, 간헐적 삭제, 예리한 삭제기구, 물이나 생리 식염수로의 배부냉각이나 외부냉각 등의 방법을 사용하고 있다.

이에 저자는 소 하악골 우각부에서 5㎜ 깊이로 천공시, 천공때 사용하는 bur의 형태(No. 6 Round bur, No. 702 fissure bur), 가하는 하중(1㎏, 2㎏ 혹은 3㎏) 냉각 여부(18℃ 0.9% 생리 식염수로의 외부냉각, 비냉각)에 따라 발생하는 마찰열의 정도를 천공 위치에

서 1㎜ 떨어진 곳에서 측정하여 비교 실험한 결과 다음과 같은 결론을 얻었다.

1. No. 6 Round bur를 사용하여 냉각하면서 1㎏하중으로 천공하였을 때, 마찰열 발생이 가장 낮았다.

2. No. 6 Round bur를 사용하여 냉각하면서 1㎏ 또는 3㎏의 하중으로 천공하였을 때, 마찰열 발생에 대한 냉각의 효과가 뚜렷하였지만 2㎏하중으로 천공한 경우는 냉각의 효과가 뚜렷하게 나타나지 않았다.

3. No. 702 Fissure bur를 사용하여 냉각하면서 1㎏ 또는 2㎏ 하중으로 천공하였을 때, 마찰열 발생이 천공 때 가하는 하중과 별 관련이 없었다.

4. 냉각하면서 2㎏하중으로 천공하였을 때, No. 6 Round bur와 No. 702 Fissure bur사이에는 마찰열 발생에 큰 차이가 없었다.

AN EXPERIMENTAL STUDY ON THE FRICTIONAL HEAT GENERATED FROM BOVINE MANDIBLES

DRILLING

Hou Yon Hwang, D.D.S.

Department of Dental Science, The Graduate School, Yonsei University

(Directed by Prof. Jung Ho Yoon, D.D.S., Ph.D.)

The removal of cancellous and cortical bone in oral and maxillofacial surgery is

frequently accomplished with burns

Heat generated from drilling is due to the friction and the fragmentation of

particles of bone at the cutting edge of the drill. The frictional heat has serious

consequences leading to hyperemia, fibrosis, osteocytic degeneration and increased

osteoclastic-osteoblastic activity, dehydration, dessication, shrinkage,

carbonization, and nercrosis.

Various techniques applied to reduce or limit frictional heat arising from

drilling included slow rotational speeds, intermittent drilling, sharp drilling

instruments, external irrigation, internal irrigation with water or saline

solution.

This study was undertaken to compare frictional heat of the No.6 round bur to the

No.702 fissure bur under the controlled condition, that is, 4800rpm, drilling force

of 1, 2, or 3kg, external irrigation with 18℃ 0.9% saline solution, no irrigation,

preparation of 5mm cavity in depth, temperature measurements at 1mm distance from

the experimental cavity, using the bovine mandibles in vitro.

The obtained results were as follows.

1. The lowest frictional heat was generated, when the No.6 round bur was used

with irrigation, with drilling force of 1kg.

2. The effect of irrigation was evident, when the No.6 round bur was used with

irrigation, with drilling force of 1kg or 3kg. but, unevident in drilling force of

2kg.

3. The frictional heat was independent of the drilling force of 1kg or 2kg, when

the No.702 fissure bur was used with irrigation.

4. There was no temperature variation between the No.6 round bur and the No.702

fissure bur, when cavity preparation was done with irrigation, drilling force of

2kg.

[영문]

The removal of cancellous and cortical bone in oral and maxillofacial surgery is frequently accomplished with burns

Heat generated from drilling is due to the friction and the fragmentation of particles of bone at the cutting edge of the drill. The frictional heat has serious consequences leading to hyperemia, fibrosis, osteocytic degeneration and increased

osteoclastic-osteoblastic activity, dehydration, dessication, shrinkage, carbonization, and nercrosis.

Various techniques applied to reduce or limit frictional heat arising from drilling included slow rotational speeds, intermittent drilling, sharp drilling instruments, external irrigation, internal irrigation with water or saline

solution.

This study was undertaken to compare frictional heat of the No.6 round bur to the No.702 fissure bur under the controlled condition, that is, 4800rpm, drilling force of 1, 2, or 3kg, external irrigation with 18℃ 0.9% saline solution, no irrigation, preparation of 5mm cavity in depth, temperature measurements at 1mm distance from the experimental cavity, using the bovine mandibles in vitro.

The obtained results were as follows.

1. The lowest frictional heat was generated, when the No.6 round bur was used with irrigation, with drilling force of 1kg.

2. The effect of irrigation was evident, when the No.6 round bur was used with irrigation, with drilling force of 1kg or 3kg. but, unevident in drilling force of 2kg.

3. The frictional heat was independent of the drilling force of 1kg or 2kg, when the No.702 fissure bur was used with irrigation.

4. There was no temperature variation between the No.6 round bur and the No.702 fissure bur, when cavity preparation was done with irrigation, drilling force of 2kg.