No abstract available.
Methods* ; Resin Cements*

The purpose of this study was to evaluate the effect of multiple application of all-in-one dentin adhesive system on microtensile bond strength using confocal laser scanning microscope and microtensile bond strength test. Flat occlusal dentin surfaces were prepared using low-speed diamond saw. In group I, Scotchbond Multipurpose (SM) was applied by manufacturer's recommendation. In group II, after Adper Prompt L-Pop was applied for 15s and light cured for 10s, the second coat was re-applied and light-cured. In group III, after light-curing the second layer, the third coat was re-applied and light-cured. Specimens bonded with a resin-composite were sectioned into resin-dentin stick for measuring the adhesive layer thickness by confocal laser scanning microscope and evaluating micro-tensile bond strength. The adhesive layers of three-step dentin adhesive system, 3 coats of Adper Prompt L-Pop had significantly thicker than SM, 2 coats of Adper Prompt L-Pop (p < 0.05). However, there was no significant differences in bond strengths between SM and 3 coats of Adper Prompt L-Pop (p > 0.05). And SM, 3 coats of Adper Prompt L-Pop had significantly higher than 2 coats of Adper Prompt L-Pop in bond strengths (p < 0.05).
Adhesives* ; Dentin* ; Diamond

We evaluated the efficacy of the optical and non-optical low vision aids on the basis of our 31 low vision patients, whose visual acuities were not corrected with the conventional glasses nor operations. Out results were following that the improved visual acuities by the low vision aids were stastically significant(p<0.01, paired t-test), and meet their needs. We think the optical and non-optical low vision aids are required to rehabilitate the visually impaired patients.
Eyeglasses ; Glass ; Humans ; Rehabilitation* ; Vision, Low* ; Visual Acuity

It was reported that the refractive power in the premature infants was more frequently myopic than in the normal, but there was little known about the onset and pathogenesis. The 106 premature infants, less than 37 weeks's gestational age, were comparatively examined at the age of 4 weeks to determine that there was myopic shift before cicatrical ROP state and the correlation of corneal diameter, axial length with refractive errors. The No-ROP group was 70 infants(140 eyes), and ROP group was 36 infants(72 eyes), and it was possible to analysis statistically only within the 33-36 post-conceptional age because the two groups were not normally distributed. The mean spherical equivalents at the 33-34 weeks were +1.91 Diopter, +1.48 Diopter in the No-ROP group and -0.21 Diopter, 0.00 Diopter in the ROP group, and this was statistically different(p<0.05), but corneal diameter and axial length were not different in both groups(p>0.05). This study revealed that the refractive errors in the ROP group were more myopic shift than in the No-ROP group in regard to early active state of ROP.
Gestational Age ; Humans ; Infant, Newborn ; Infant, Premature ; Refractive Errors* ; Retinopathy of Prematurity

Universal adhesives that simplify bonding procedures and be used in multi-etch mode have been developed. In this study, the effects of agitation and solvent evaporation time of a universal adhesive on microtensile bond strength (µTBS) were evaluated by varying the times of these two procedures. Eighteen human molars were used to fabricate specimens, and the teeth were randomly divided into six experimental groups. Each group had different agitation time (5 s, 10 s, 20 s) and evaporation time (10 s, 20 s). The specimens were cut into a rod-shape with a cross-sectional area of 1 mm2 , and their µTBS was measured. The data were analyzed using an ANOVA and Tukey’s post hoc test. After this, the debonded surface was observed using scanning electron microscopy (SEM). In the groups with a solvent evaporation time of 20 s, µTBS was statistically higher, even with a short agitation time (p<0.05). Furthermore, for the groups with the shorter evaporation time, bonding strength decreased statistically as the agitation time shortened (p<0.05). The results of this experiment suggest that if the solvent was adequately evaporated, sufficient bonding strength could be obtained even when the adhesive was agitated for a short time. This is supported by the results of SEM image analysis, which revealed a uniform adhesive layer with well-infiltrated tags in the groups with the prolonged evaporation time. It may be crucial to secure an adequate evaporation time in order to obtain optimal bonding strength.

The purpose of this study was to evaluate the effects of deproteinization and an additional primer treatment on the microtensile bond strength of a newly developed self-adhesive resin cement to dentin. The occlusal dentin of extracted human third molars was randomly divided into four groups according to the surface treatment: a control (CON) with no treatment; applying a deproteinizing agent (DPT) (5% sodium hypochlorite); using a primer (PRI) (G-CEM ONE Adhesive enhancing primer, GC); and applying a deproteinizing agent and a primer (DPT-PRI). Composite resin blocks with a disk shape (diameter, 10 mm; height, 4 mm) were bonded to the treated dentin using a self-adhesive resin cement (G-CEM ONE, GC). The specimens were sectioned into sticks with a cross-section of 1 mm² and tested to failure in tension mode at a crosshead speed of 1 mm/min. All groups showed a significantly higher microtensile bond strength compared to CON (p<0.05). PRI showed the highest microtensile bond strength followed by DPT and DPT-PRI (p<0.05). No significant differences were observed between DPT and DPT-PRI (p>0.05). Within the limitations of this study, a deproteinizing agent or specific primer can enhance the microtensile bond strength of the self-adhesive resin cement to dentin. However, it is not recommended to use a primer in combination with the deproteinizing agents.
Adhesives ; Dentin ; Humans ; Molar, Third ; Resin Cements ; Sodium ; Sodium Hypochlorite

Universal adhesives that simplify bonding procedures and be used in multi-etch mode have been developed. In this study, the effects of agitation and solvent evaporation time of a universal adhesive on microtensile bond strength (µTBS) were evaluated by varying the times of these two procedures. Eighteen human molars were used to fabricate specimens, and the teeth were randomly divided into six experimental groups. Each group had different agitation time (5 s, 10 s, 20 s) and evaporation time (10 s, 20 s). The specimens were cut into a rod-shape with a cross-sectional area of 1 mm2 , and their µTBS was measured. The data were analyzed using an ANOVA and Tukey’s post hoc test. After this, the debonded surface was observed using scanning electron microscopy (SEM). In the groups with a solvent evaporation time of 20 s, µTBS was statistically higher, even with a short agitation time (p<0.05). Furthermore, for the groups with the shorter evaporation time, bonding strength decreased statistically as the agitation time shortened (p<0.05). The results of this experiment suggest that if the solvent was adequately evaporated, sufficient bonding strength could be obtained even when the adhesive was agitated for a short time. This is supported by the results of SEM image analysis, which revealed a uniform adhesive layer with well-infiltrated tags in the groups with the prolonged evaporation time. It may be crucial to secure an adequate evaporation time in order to obtain optimal bonding strength.

Complicated crown fractures of maxillary anterior teeth caused by trauma in adolescence can cause functional and aesthetic problems. For crown fractures with pulp exposure, various restorative methods can be considered depending on the amount of remaining tooth structure. Direct resin restorations are the most traditional and effective method, but they are likely to discolor and break over time. Fixed prosthesis have a high possibility of re-restoration due to marginal disharmony due to tooth movement during the growth period, and restorations using post which are mainly performed for extensive crown fractures increase the risk of root perforation and root fracture. However, endocrown is an integrated structure that gains retention force from the pulp space, enabling effective reconstruction from a biomechanical perspective and providing advantages in restoring function and aesthetics.Therefore, endocrown can be considered as a restoration method for complicated crown fractures caused by trauma in adolescence.

PURPOSE: In the WHO classification of breast carcinoma, invasive ductal carcinoma with predominant intraductal component (IDC with PIC) has been defined as carcinomas in which the component of ductal carcinoma in situ amounts to four times more than the invasive element in area. This study was designed to evaluate the clinicopathological significance of IDC with PIC. METHODS: Five hundred and seventy nine patients with breast cancer (154 IDC with PIC and 425 with T1 invasive ductal carcinomas) treated with mastectomy or breast conserving surgery between 1989 and 1998 at the Asan Medical Center were divided into two study groups (IDC with PIC and T1 IDC) and compared the clinicopathological characteristics and survival of both groups. RESULTS: By comparison with the T1 IDC, the IDC with PIC has several distinct features including younger mean age of occurrence (45.3 years vs 48.3 years, p=0.002), larger mean tumor size (3.5 cm vs 1.6 cm, p<0.001), lower incidence of axillary lymph node metastasis (15.7% vs 31.3%, p<0.001) and estrogen receptor positivity (45.7% vs 59.2%, p=0.03), higher incidence of low histologic grade (78.7% vs 61.7%, p=0.002) and cancer detection rate by screening without symptom (21.6% vs 11.5%, p=0.003) or clinical manifestation of nipple discharge (17.3% vs 4.3%, p<0.001) and microcalcification with or without mass on mammography (58.7% vs 30.2%, p<0.001). There were no significant difference in the cumulative 5-year overall and disease-freesurvival rates (93.1% vs 90.1%, p=0.78; 89.5% vs 86%, p=0.23). In the IDC with PIC group, tumors larger than 2 cm in size were more frequently metastasized to axillary lymph nodes than tumors smaller than 2 cm, but this finding was not significant (p=0.07). CONCLUSION: Invasive ductal carcinoma with predominant intraductal component showed less invasive and more low-grade malignant characteristics than T1 invasive ductal carcinoma. Survival was not statistically different.
Breast Neoplasms* ; Breast* ; Carcinoma, Ductal* ; Carcinoma, Intraductal, Noninfiltrating ; Chungcheongnam-do ; Classification ; Estrogens ; Humans ; Incidence ; Lymph Nodes ; Mammography ; Mass Screening ; Mastectomy ; Mastectomy, Segmental ; Neoplasm Metastasis ; Nipples

PURPOSE: In the WHO classification of breast carcinoma, invasive ductal carcinoma with predominant intraductal component (IDC with PIC) has been defined as carcinomas in which the component of ductal carcinoma in situ amounts to four times more than the invasive element in area. This study was designed to evaluate the clinicopathological significance of IDC with PIC. METHODS: Five hundred and seventy nine patients with breast cancer (154 IDC with PIC and 425 with T1 invasive ductal carcinomas) treated with mastectomy or breast conserving surgery between 1989 and 1998 at the Asan Medical Center were divided into two study groups (IDC with PIC and T1 IDC) and compared the clinicopathological characteristics and survival of both groups. RESULTS: By comparison with the T1 IDC, the IDC with PIC has several distinct features including younger mean age of occurrence (45.3 years vs 48.3 years, P=0.002), larger mean tumor size (3.5 cm vs 1.6 cm, P<0.001), lower incidence of axillary lymph node metastasis (15.7% vs 31.3%, P<0.001) and estrogen receptor positivity (45.7% vs 59.2%, P=0.03), higher incidence of low histologic grade (78.7% vs 61.7%, P=0.002) and cancer detection rate by screening without symptom (21.6% vs 11.5%, P=0.003) or clinical manifestation of nipple discharge (17.3% vs 4.3%, P<0.001) and microcalcification with or without mass on mammography (58.7% vs 30.2%, P<0.001). There were no significant difference in the cumulative 5-year overall and disease-free survival rates (93.1% vs 90.1%, P=0.78; 89.5% vs 86%, P=0.23). In the IDC with PIC group, tumors larger than 2 cm in size were more frequently metastasized to axillary lymph nodes than tumors smaller than 2 cm, but this finding was not significant (P=0.07). CONCLUSION: Invasive ductal carcinoma with predominant intraductal component showed less invasive and more low-grade malignant characteristics than T1 invasive ductal carcinoma. Survival was not statistically different.
Breast Neoplasms* ; Breast* ; Carcinoma, Ductal* ; Carcinoma, Intraductal, Noninfiltrating ; Chungcheongnam-do ; Classification ; Disease-Free Survival ; Estrogens ; Humans ; Incidence ; Lymph Nodes ; Mammography ; Mass Screening ; Mastectomy ; Mastectomy, Segmental ; Neoplasm Metastasis ; Nipples