• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.41 no.2
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• pp.109-115
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• 2015

Odontoma is the most common odontogenic benign tumor, and the treatment of choice is generally surgical removal. After excision, bone grafts may be necessary depending on the need for further treatment, or the size and location of the odontoma. Although the osteogenic capacity of a demineralized tooth was verified as early as 1967 by Urist and many other investigators, the cumbersome procedure, including a long demineralization time, may be less than comfortable for clinicians. A modified ultrasonic technology, with periodic negative pressure and temperature control, facilitated rapid and aseptic preparation of demineralized teeth for bone grafts. This approach reduces the demineralization time dramatically (${\leq}80$ minutes), so that the graft material can be prepared chairside on the same day as the extraction. The purpose of this article is to describe two cases of large compound odonotomas used as graft material prepared chairside for enucleation-induced bony defects. These two clinical cases showed favorable wound healing without complications, and good bony support for future dental implants or orthodontic treatment. Finally, this report will suggest the possibility of recycling the benign pathologic hard tissue as an alternative treatment option for conventional bone grafts in clinics.

• The Journal of the Korean dental association
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• v.58 no.6
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• pp.324-335
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• 2020

We investigated whether fluoride varnishes recover the hardness of bovine teeth under 20 days of demineralization/remineralization cycling. The fluoride varnish groups (two commercial fluoride varnishes [V-varnish (Vericom, Korea) and CavityShield (3M ESPE, USA)] and an experimental fluoride varnish including 5 wt.% NaF were compared with a control group without fluoride varnish. Vickers hardness was measured at baseline, 3 days after immersion in caries-inducing solution, 24 hours after application of a fluoride varnish, and after 10 and 20 days of demineralization/remineralization cycling. Afterward, tooth surfaces were observed by scanning electron microscope. After fluoride varnish application and the cycling 10 and 20 days, the experimental varnish group showed the highest hardness, while the CavityShield and the control groups demonstrated the lowest hardness. The experimental varnish group recovered the hardness of the baseline at 24 hours after application of the varnish, while it was recovered after 20 days of the cycling in case of the V-varnish. However, the CavityShield and the control groups did not recover the hardness even after 20 days of the cycling. The experimental fluoride varnish with fast recovery in the hardness of the baseline can be used as an effective fluoride varnish to resist demineralization and to facilitate remineralization.

• Restorative Dentistry and Endodontics
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• v.21 no.2
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• pp.470-488
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• 1996

The end products of the metabolism of the oral microorganism, organic acids, are an element that produces dental caries. Four organic acids in plaque fluid, lactic acid, acetic acid, succinic acid, propionic acid which take the important role in producing dental caries, were chosen to evaluate the effect of acid type and concentration. The subject, $100{\mu}m$ in thickness, were immersed in acid-buffer solution which has the different acid concentration of 10mM, 25mM, 50mM, 100mM and pH 4.3 and degree of saturation was $0.153{\pm}0.003$ kept in constant and were operated to produce artificial caries under different demineralization time (1, 2, 3 day) at x25. The results were obtained by observing under polarizing microscope at x25. 1. The subsurface lesion, specific finding of incipient enamel caries, showed positive birefringence. but surface zone and sound enamel showed negative birefringence. 2. The demineralization rate of enamel was increased as the acid concentration increased. 3. The subsurface lesion showed increasing depth in the order of lactic, acetic, propionic acid, succinic acid. 4. The concentration of organic acid in artificial caries system had an independent effect on demineralization rate in enamel under the constant pH and degree of saturation. The result of this study showed that not only pH and the acid strength but the concentration of organic acid had an independent effect on demineralization rate in early enamel caries. And through the further research on the factors influencing enamel demineralization, it will be necessary to develop an effective caries preventive therapy.

• Journal of the korean academy of Pediatric Dentistry
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• v.44 no.4
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• pp.412-418
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• 2017

During orthodontic treatment, formation of white spot lesions (WSLs) around brackets has long been recognized as a potential risk. This study performed to investigate effect of preventing enamel demineralization and remineralization by application of fluoride-containing orthodontic primer. Fifty extracted bovine incisors teeth were randomly allocated to 3 groups: (I) Non-preparation specimens, (II) Application of Light Bond$^{TM}$ as fluoride containing orthodontic primer, (III) Application of Transbond$^{TM}$ XT Primer as traditional orthodontic primer without fluoride. Each group is demineralized under artificial carious solution. The demineralization pattern was evaluated using a Q-ray view, Vickers hardness test and polarized light microscope. The remained primer was calculated as 35 - 50%. The highest surface microhardness was shown on Light Bond$^{TM}$ surface. There were statistically significant differences in Vickers microhardness number between adjacent areas of Light Bond$^{TM}$ and non-prepared area. There was almost no demineralization of the enamel surface under the Light Bond$^{TM}$. At the adjacent site of Light Bond$^{TM}$, the shallow caries pattern and remineralization appearance were also observed. These results suggest that the use of fluoride-containing primers may be useful for bracket attachment to reduce enamel demineralization during orthodontic treatment.

• The korean journal of orthodontics
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• v.40 no.4
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• pp.212-226
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• 2010

Objective: The aim of this study was to evaluate the effect of remineralization and inhibition to demineralization after fluoride gel (acidulated phosphate fluoride, APF) or hydroxyapatite (HAp) paste application on interdentally stripped teeth. Methods: After interdental stripping, 1.23% APF or 5%, 10% HAp paste were applied for 7 days for remineralization. Afterwards, teeth were exposed to lactate carbopol buffer solution for demineralization. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) were used to compare change in surface contents and crystal structures after remineralization, and then after demineralization. Results: EDS analysis indicated that calcium (p < 0.001) and phosphate (p < 0.01) contents were increased after 10% HAp paste application on stripped enamel, calcium (p < 0.05) and phosphate (p < 0.01) contents were increased after 5% HAp paste application, and fluoride (p < 0.01) contents were increased after 1.23% APF application. SEM image showed that enamel surfaces became smoother and crystal structures became small and compact after APF or HAp application. After demineralization, calcium (p < 0.05) and phosphate (p < 0.05) contents remained increased on the enamel remineralized with 10% HAp paste, and phosphate (p < 0.05) contents remained increased on the enamel remineralized with 5% HAp paste. After demineralization, surfaces looked less destroyed in the enamel remineralized beforehand than those of the control, and small pores between crystal structures, formed by remineralization were remained. Conclusions: Hydroxyapatite paste and fluoride gel were helpful to remineralize and inhibit deminerlization on stripped enamel.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.1
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• pp.153-160
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• 2003

The purpose of study was to evaluate the effects of the $CO_2$ laser irradiation on demineralization inhibition and rehardening of human primary tooth enamel by laser fluoresecence measurement. Enamel specimens were made from the human primary teeth. The center spots of the specimens about 2 mm diameter were irradiated by $CO_2$ laser at the conditions of focused continuous or defocused pulsed, 3 or 6 W, for 4 seconds, before or after the demineralization by Coca-Cola for 24 hours at $37^{\circ}C$. The Diagnodent was used to measure the degree of demineralization and rehardening. There was no significant difference between focused continuous and defocused pulsed irradiation. 6W irradiation inhibited the demineralization but 3W did not. 6W irradiation rehardened the demineralized enamel but 3W did partially. The color of enamel was changed to brown to black after 6W irradiation but 3W caused no color change. $CO_2$ laser irradiation showed the effects on demineralization inhibition and rehardening of human priamary tooth enamel, and the laser fluoresecence measurement technique seemed to be a valid evaluation method.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.2
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• pp.320-325
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• 2003

The purpose of study was to investigate the effect of carbon dioxide laser on demineralization inhibition and rehardening of primary tooth enamel according to its power and irradiation time. 2mm diameter circle on the primary enamel surface was irradiated by defocused $10.6{\mu}m$ superpulse carbon dioxide laser at 6 Watt 2 seconds or at 3 Watt 8 seconds, before or after demineralization by Coca-Cola for 24 hours. Enamel surface change was measured by the Diagnodent. The results were analyzed with the former study results of 3 Watt 4 seconds and 6 Watt and 4 seconds. Diagnodent scores increased significantly after demineralization of irradiated enamel at 6W 2s or 3W 8s (P<0.05). Among the four groups, only 6W 4s group showed obvious demineralization inhibition effect. Diagnodent scores reduced significantly after 6W 2s or 3W 8s irradiation of demineralized enamel(P<0.05). Among the four groups, 6W 4s showed nearly complete rehardening effect, and the other groups showed partial effect. Tooth discoloration only occurred at 6W 4s. It seemed that caries inhibition and tooth discoloration depend on laser power more than total irradiation energy.

• Journal of the korean academy of Pediatric Dentistry
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• v.25 no.4
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• pp.825-836
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• 1998

The intention of this study was to investigate the preventive effect of chlorhexidine varnish on enamel demineralization. The sample consisted of 57 first premolars scheduled to be extracted for orthodontic purposes. The control group (N=10) was left untreated and the experimental groups were worn with specially designed stainless steel orthodontic bands on premolar for plaque accumulation. The group 1 (N=9) was worn band only, the group 2 (N=19) was applied with chlorhexidine varnish for one time, and the group 3 (N=19) was applied with chlorhexidine varnish for 3 times once a week. After 4 weeks of experimental periods, every specimen were examined by SEM and Vickers hardness test to evaluate and compare the degree of enamel decalcification. The results were as follows: 1. Although SEM revealed various degree of enamel demineralization in every experimental groups, the group 1 showed more severe demineralizations than the group 2 and 3. 2. The mean Vickers Hardness Numbers measured in this study seemed to reveal that there was a statistically significant difference between the control goup and the group 1 (P<0.05), and also a significant difference between the group 1 and the group 2, 3 (P<0.05). And there was no significant difference between the group 2 and the group 3 (p>0.05). 3. The results of VHN did not deemed to show a statistically significant difference between maxillary premolar and mandibular premolar in both group 2 and group 3 (P>0.05).

• Applied Chemistry for Engineering
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• v.7 no.6
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• pp.1115-1124
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• 1996

An MCL(Molten Caustic Leaching) treatment is a chemical refinery process which is used for the desulfurization and demineralization by alkali treatment. The MCL treatment removes ash by converting mineral like Si, Fe, V, Ni etc. in petroleum cokes into soluble salts. The MCL has an advantage minimizing carbon loss in comparison to other desulfurization process. Reaction variables for the desulfurization and demineralization in the study were leaching temperature, leaching time, ratio of caustic to cokes, acid concentration and time for washing, and particle size. At the optimum condition, above 99% of desulfurization and about 90% of demineralization was obtained. FT-IR and SEM analysis showed that the structure and surface of the particle was closely related with the degree of sulfur and ash removal, and leaching temperature as well.

• Restorative Dentistry and Endodontics
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• v.26 no.4
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• pp.341-349
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• 2001

Dental caries is the most common oral disease. There are many factors contributing to its development, but complete understanding and prevention are not fully known. However, it is possible to remineralize the early enamel curious lesion by fluoride containing remineralization solution. Recently the pH-cycling model has been used to examine the effect of fluoride solution on remineralization of artificial caries in vitro as it can closely simulate the conditions encountered in vivo within a carefully controlled environment. The aim of this study was to evaluate the remineralizing effects of supersaturated buffer solutions under pH-cycling model. The specimen with 3mm-diameter was made using mature bovine incisors which has no caries and has sound enamel surface. Early curious lesions were produced by suspending each specimens into demineralization solution at pH 5.0 for 33 hours and the specimen whose surface hardness value ranged from 25 to 45 VHN were used. The pH cycling treatment regimen consisted of 5 min soaks of three treatment solutions four times per days for 15 days and the continuous cycling of demineralization and remineralization were carried out for 15 days. Following the pH-cycling treatment regimen, the specimens' surface microhardness were measured by the Vickers hardness test (VHN) and analyzed by ANOVA and Duncan's multiple-range test. 1. The surface microhardness value of supersaturated solution, Senstime, and Gagline groups were increased after pH cycling, and that of supersaturated solution was significantly Increased compared to saline group(P<0.05). 2. The surface remineralization effect of fluoride containing solutions was accelerated by saliva under pH-cycling mode 3. The pH cycling model was considered appropriate to mimic the intra-oral pH changes when evaluating demineralization and remineralization in vitro. Under the results of above study, salivary remineralization effect can be improved by fluoride containing remineralization solution. The pH-cycling model was considered appropriate to mimic the intra-oral pH changes when evaluating demineralization and remineralization in vitro.