• The Journal of the Korean dental association
• /
• v.26 no.5 s.228
• /
• pp.384-388
• /
• 1988

• Journal of the korean academy of Pediatric Dentistry
• /
• v.27 no.1
• /
• pp.85-89
• /
• 2000

There has recently been some trials to add the fluoride-releasing property to existing fissure sealants and some of them are already commercially available. But, some questions mat naturally be arisen regarding the potential decrease of physical properties by adding the fluoride despite its new caries-inhibiting abilities. This study was performed for the purpose of comparing the shear bond strengths of conventional composite sealant, Fluoride-releasing sealant and glass ionomer sealant, and obtained the results as fellows. 1. Two kinds of composite sealants (Helioseal and Teethmate-A) showed slightly higher bond strength than Fluoride-releasing sealant(Teethmate-F) without any significance(p>0.05). 2. Class ionomer sealant (Fuji III) was much lower than composite sealant in shear bond strength(p<0.05). 3. With the result of this study, it was found that there is little effect on retentive properties of sealants by adding fluoride to amplify the caries-inhibiting properties.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.23 no.4
• /
• pp.906-914
• /
• 1996

Due to the various reason, sealing of pit & fissure might be imperfect. One of these reason can be the fracture of sealant material because of the low hardness value of sealing material. The purpose of this in vitro study was to evaluate the microhardness of two different curing type pit and fissure sealants: Dual-cure and Light-cure. The result from the present study can be summarized as follows: 1. All pit and fissure sealants that used in this study showed statistically significant difference in their microhardness of upper and lower surface. (P <0.05) 2. Except of lower surface of teethmate, microhardness of 40-second curing sealant was statistically higher than that of 20-second curing sealant. (P <0.05) 3. In comparison of sealants, microhardness of dual-cure sealant was statistically higher than that of light-cure sealant. Above results suggest that the use of dual-cure sealant and longer curing time are recommended.

• The Journal of the Korean dental association
• /
• v.47 no.5
• /
• pp.252-259
• /
• 2009

치면세균막관리는 치주병과 치아우식증을 예방하는 데 필수적이다. 이러한 치면세균막관리는 자가관리와 전문가관리로 구분할 수 있는데, 이 두가지를 병행하였을 때 특히 건강한 치주를 유지하는데 도움을 준다. 자가관리는 1회성 교육으로는 불충분하며 체계적인 반복교육이 필요하다. 전문가관리는 대상자의 구강상태에 따라 일정한 주기로 계속 시행되어야 하며 $3{\sim}6$개월 주기가 바람직하다. 반복교육과 계속관리과정으로 진행되는 자가 및 전문가 치면세균막 관리 중에 대상자의 구강병 위험요소에 따라 불소도포와 치면열구 전색 등이 제공될 수 있다.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.29 no.2
• /
• pp.255-261
• /
• 2002

The purpose of this study was to compare the microleakage pattern of flowable composite resin to sealant, composite resin used in preventive resin restoration and glass ionomer cement used as liner. 120 extracted sound human molars were divided into 6 groups : group 1 and 2:sealant ; group 3 and 4:preventive resin restoration ; group 5 and 6:sandwich technique restoration. For the experimental groups(group 2, 4 and 6), flowable composite resin(Tetric flow) was used. For the control group, Concise was used as sealant material(group 1), Z-100 with Concise were used as preventive resin restoration(group 3), and Vitrebond was used as cavity liner(group 5). All the restorations were thermocycled and the degree of dye penetration was evaluated with stereomicroscope. The microleakage of each group was measured and statistically analyzed. The results of the present study were as follows : 1. In group 1 and 2, there was no statistically significant difference in microleakage between Concise and Tetric flow(p>0.05). 2. In groups of preventive resin restorations, there was no statistically significant difference in microleakage between Z-100 with Concise and Tetric flow(p>0.05). 3. The microleakage of Vitrebond and Tetric flow used as liner showed no statistically significant difference(p>0.05).

• Journal of Oral Medicine and Pain
• /
• v.30 no.2
• /
• pp.277-285
• /
• 2005

The purpose of this study was to evaluate photothermal effect of laser, which eliminates and reduces bacteria causing periodontal disease, on treatment of periodontal disease. This study included subjects with moderate periodontitis who visited the Department of Oral Medicine, College of dentistry, Yonsei University. The subjects were divided into experimental group, where Argon laser treatment was used, and control group, where conventional subgingival curettage was used. Gingival fluids from each subject were collected prior and after 1 week of the treatment, and changes in number of bacterial colonies cultured from aerobic as well as anaerobic bacteria responsible for the periodontal disease, and changes in clinical indices related to the periodontal disease, such as plaque index, gingival index, sulcus bleeding index, were analysed. As a result, the number of bacterial colonies of aerobic and anaerobic bacteria reduced after 1 week of the treatment in both groups, especially the bacterial colonies of anaerobic bacteria which showed statistically significant reduction(p<0.1). However, there was no significant difference between the experimental group and the control group. Clinical indices including plaque index, gingival index, sulcus bleeding index were reduced after 1 week of the treatment in both groups. In the experimental group, gingival index(p<0.1) and sulcus bleeding index(p<0.01) showed significant reduction, and, in the control group, sulcus bleeding index(p<0.01) showed significant reduction. However, there were no significant differences in each indices between the two groups. The above results suggest that Argon laser could be used as a substitute of conventional subgingival curettage, or in combination with subgingival curettage which would increase the effect of the treatment. Although the possibility of clinical application of Argon laser was observed in this study, more randomized-controlled research, including acquirement of sufficient samples as well as long-termed follow up, would be necessary before clinically effective application of Argon laser.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.10 no.1
• /
• pp.77-83
• /
• 1983

The purpose of this study was to observe the microleakage of a pit and fissure sealant at the tooth-restoration interface. One hundred and sixty-seven extracted permanent and deciduous teeth were used and some simple mechanical pretreatment were done before etching. The degree of microleakage was assessed by $Ca^{45}$ after 24 hours, and 2 months. The results were as follows: 1. Among total 167 teeth, 53 teeth (32%) were demonstrated the microleakage. 2. After 2 months the leakage was increased from 22 percent to 35 percent in permanent teeth, and from 32 percent to 43 percent in primary teeth. 3. The group treated by fluoride paste was demonstrated the largest leakage, 50 percent in primary teeth and 33 percent in permanent teeth. There are more leakage in primary teeth (38%) than permanent teeth (28%).

• Journal of the korean academy of Pediatric Dentistry
• /
• v.32 no.2
• /
• pp.321-331
• /
• 2005

The purpose of this study was to compare the effectiveness of mechanical and acid treatment on enamel surfaces for the retention of pit and fissure sealants and evaluate the presence of a prismless layer. The etch pattern produced on enamel from immature and mature premolar teeth extracted with varying period of acid etching using 37% phosphoric acid was examined using a scanning electron microscope(SEM). The composition of each groups was evaluated using an energy dispersive x-ray(EDX) spectroscopy. The result of present study can be summarized as follows: 1. Prismless layer was commonly observed on the fissure enamel in young and mature premolar. 2. There were no differences in micro-structure and etching pattern on fissure enamel between the young and the mature premolar. 3. The most effective etching pattern for retention of pit and fissure sealant was observed in 60 seconds of etching time and no apparent difference of etching pattern was found among 15, 30, and 45 seconds of etching time which showed non-retentive etching patterns. 4. The etching pattern obtained by grinding enamel surface with bur followed by 60 seconds of etching was similar to that of 60 seconds of etching without any pretreatment of fissure surface. 5. Type 2 etching pattern was commonly found on fissure enamel in both young and mature premolar. 6. The calcium content and P/Ca ratio in fissure enamel between the young and the mature premolar were significantly different(P<0.05). But content of calcium, phosphate and P/Ca ratio on various regions of fissure enamel in both young and mature premolar did not showed any difference. Based on these results, prismless layer may negatively influence the retention of pit and fissure sealants. Therefore, the mechanical removal of the prismless layer by grinding prior to etching or by prolonged etching time of enamel within the fissure system should result in an improved bonding of a pit and fissure sealant.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.33 no.2
• /
• pp.336-347
• /
• 2006

Pit and fissure sealants has been proven as safe and effective method of caries prevention. But improper application of pit and fissure sealant may masking the caries process in occlusal fissure. Dentists have to understand the correct and exact application method of pit and fissure sealant for he good result of caries prevention. A key factor to enhanced the effectiveness of caries prevention is retention of pit and fissure sealant. Deep penetration of material into fissure and least marginal leakage around the fissure orifice are the major concerns for dentists to achieve the successive application of pit and fissure sealants. This paper reviewed the literature on the pit and fissure sealants under the following subtitles for enhanced retention : (1) application timing, (2) Indication, (3) Occlusal prophylaxis, (4) Materials, (5) Penetration, (5) Recall check Dental profession must perform the exact application of pit and fissure sealant because this procedure is one of the most technique-sensitive one in dental field.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.25 no.4
• /
• pp.761-771
• /
• 1998

In this study, attempt has been made to evaluate the effect of $CO_2$ laser irradiation on enamel surface structure and the bond strength of sealant material. Conventional acid etching was used as a control technic for comparison. The results obtained from this experiment were as follows; 1. The highest mean shear bond strength value was observed in samples of Group I (acid-etching) with the statistical significance(p<.05) between all the other groups. 2. The shear bond strength in Group IV was the lowest among laser etching groups. but there were no significant difference between them(p>.05). 3. Scanning electron microscopic observation showed that the rough and irregular surface was created by $CO_2$ laser treatment with the formation of numerous pores, micro-cracks, and small bubble-like inclusion. Increasing the energy density induced localized surface melt with a thin smooth glaze-like appearance. 4. In acid-etched control specimen cohesive failure predominated, whereas adhesive failure was the main mode in laser-treated group. Based upon the above-mentioned results, it can be assumed that the $CO_2$ laser is not an adequate substitute for the acid-etch technique in enamel preconditioning. More studies are required to explore the effective condition of laser irradiation which could attain the better bond strength of restorative materials.