IN VITRO STUDY ON THE EFFECTS OF THE FLOURIDE ON THE REMINERALIZATION OF ACID ETCHED ENAMEL

불소가 산부식된 법랑질의 재석회화에 미치는 영향에 관한 연구

Remineralization of acid-etched enamel across the time has been one of the curiosities in the context of the orthodontic biomechanics(Arends J. et al., IRL Press, 1, 1985), nevertheless, is so far controversial. It was the aim of this study to observe the remineralization patterns of acid-etched enamel across the time and whether the existence of fluoride might carry out any modifications. The intact buccal surfaces of the first bicuspids which was extracted for orthodontic treatment were ground smooth, and etched with a 38w/w% phosphoric acid for 60 seconds, The surface was observed by the scanning electron microscope and surface microhardness was measured after immersion in the fluoride or non-fluoride containing remineralizing solution for 0 hour, 12 hours, 1 day, 3 days, 7 days, 14 days, 28 days, and 42 days. The following results and conclusions were drawn; 1. Surface microhardness increased in both fluoride containing and non-fluoride containing solution group with time lapse. 2. In fluoride containing solution group, the surface microhardness sharply increased at the 12 hours group, on the other hand, surface microhardness increased at 3 days in non-fluoride containing solution group. 3. The difference in microhardness value between two groups manifested gradual decrease. 4. Scanning electron microphotographs disclosed that the fluoride containing solution group generated spiculate sub-stances in the 12 hours group, which was increased in number and size with time lapse. 7 days later, spherical composure was began to be produced, The spiculate substances so much increased in number that the etched enamel surface looked like flat in 42 days. 5. In non fluoride-containing solution group, there was no surface change at 42 days, perceivable in scanning electron microphotographs which could be defined as remineralization though the surface was a little rougher than the incipient etched surface. These results demonstrate that the action of the fluoride is exceedingly pertinent in the remineralization of acid-etched enamel and the remineralization process goes uninterruptedly with time lapse.

치과교정장치의 장착을 위하여 치아법랑질표면을 산부식하는 것은 일반화된 술식이며, 산부식된 법랑질표면은 재석회화되어 자연적으로 정상상태를 회복하는 연구보고되어 왔다. 이 연구의 목적은 산부식된 법랑질표면의 재석회화에 불소가 미치는 영향을 실험적으로 관찰하여 재석희화의 일면을 구명하는데 있다. 교정치료목적으로 발거한 사람 제1소구치 치관을, 불소함유 석회화용액과 불소무함유 석회화용액에 12시간, 1일, 3일, 7일, 14일, 28일, 42일간 담구어 보관한후, 법랑질표면의 미세경도측정과 주사전자현미경관찰을 통하여 법랑질 표면의 변화들을 경시적으로 관찰하여 다음의 결과를 얻었다. 1) 표면미세경도는 불소함유 여부에 관계없이 시간경과에 따라 증가하였으며, 불소함유군 은 12시간부터, 불소무 함유군은 3일경과후부터 현저히 증가하였으나, 시간경과에 따라 그 차이는 감소하였다. 2) 주사전자현미경 관찰에서 불소함유용군은 12시간후부터 법랑질표면에 침상물질이 침착되기 시작하여 42일 후에는 편평한 표면으로 되었으나, 불소무함유용군은 전실험기간동안 산부식직후보다 약간 더 거칠어졌으나, 산부식 된 법랑질표면이 그대로 관찰되었다. 이상의 결과로부처 불소는 산부식된 법랑질표면의 재석회화 시기를 앞당기는 효과가 있으며, 재석회화의 소요시간도 단축하는 효과가 있음이 확인하였다.