• Restorative Dentistry and Endodontics
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• v.14 no.2
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• pp.38-48
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• 1989

The purpose of this study was to investigate the proper consistency of root canal sealer needed in obtaining an efficient canal obturation in injection-thermoplasticized low-temperature ($70^{\circ}C$) gutta-percha method. The sealer was made by incorporating zinc oxide powder into $0.5m{\ell}$ of eugenol and then the $0.5m{\ell}$ of mixture slurry was placed between two flat glass plates. The consistency was determined by measuring the degree of spread of the slurry at loading the 120gm of weight from the top plate. The sealer was prepared according to P/L ratio corresponding to the acquired consistency of 65.45mm, 46.80mm, 28.95mm and 22.60mm. The distal roots were obtained by cutting off from 125 extracted human lower molars and the root canals were prepared by using step-back method. The prepared canals were coated with the sealers on their walls and obturated by using the injection-thermoplasticized low-temperature ($70^{\circ}C$) gutta-percha method. All specimens were immersed in 2% methylene blue dye solution for 48 hours at $37^{\circ}C$. Calipers was used to measured the dye penetration into the root canals from apical constrictions. The results were as follows : The canals obturated without sealer showed significantly more leakage than the canals obturated with sealer. Within the consistency from 65.45mm to 22.60mm, the sealer of 65.45mm appeared significantly better than that of 28.95mm and 22.60mm in the canals obturated by injection-thermoplasticized gutta-percha method, and better than that of 46.80mm without statistical significance.

• Restorative Dentistry and Endodontics
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• v.45 no.3
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• pp.34.1-34.7
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• 2020

Objectives: This study evaluated by using micro-computed tomography (micro-CT) the filling ability and sealer apical extrusion promoted by a new Sealer Injection System (SIS; Angelus) with side openings needle, in comparison with the conventional injection system, associated with a new ready-to-use calcium silicate-based sealer (Bio-C Sealer). Materials and Methods: Acrylic resin models containing a main curved artificial canal and 3 simulated lateral canals in apical, middle and cervical thirds were used. The main root canals were prepared using a rotary system up to size 35.05. The canals were filled with Bio-C sealer by using a single cone technique and the conventional delivery system or SIS. Samples were scanned in micro-CT. The percentage of voids throughout the entire extension of the main root canal and in each third of the lateral canals, besides the apical extrusion of the sealer was calculated. Data were submitted to t-test (p < 0.05). Results: There was no difference between both systems in the main root canals filling. Although the volume percentage of voids was similar in the apical and middle thirds of lateral canals, SIS had the greatest filling ability of the cervical third lateral canal. Moreover, the conventional system showed the highest apical extrusion of the sealer. Conclusions: The conventional and SIS obturation systems had an appropriate filling ability of the main root canal. SIS had the best filling of the cervical third of the lateral canals, besides lower sealer apical extrusion, suggesting its clinical indication.

• Restorative Dentistry and Endodontics
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• v.19 no.2
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• pp.429-446
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• 1994

The purpose of this study was to evaluate the sealing effect of warm lateral condensation technique by Endotec spreader, comparing with other canal filling techniques. One hundred and forty extracted human teeth with single canal were instrumented and randomly divided into four groups according to canal filling techniques including lateral condensation with sealer, warm lateral condensation with sealer, warm lateral condensation without sealer, and injection-molded thermoplasticized gutta-percha without sealer. Obturated canals were exposed to 2 % methylene blue solution at $37^{\circ}C$ for 24 hours and measurement of the degree of microleakage was done linearly and volumetrically with stereozoom microscope and UV-spectrophotometer respectively. The results were as follows ; When sealer was used, the canals obturated by warm lateral condensation showed less leakage linearly and volumetrically than the canals obturated by standard lateral condensation with no statistically significant difference. The obturated canals by warm lateral condensation with sealer showed less leakage linearly and volumetrically than the canals obturated by warm lateral condensation without sealer and by injection-molded thermoplasticized gutta-percha without sealer with statistical significance (p<0.05). No statistical difference revealed that the group filled with the use of the Endotec had significantly less leakage than any of the other groups. There was a significant correlation between the linear measurement and volumetric measurement(r=0.4459, p<0.05).

• Restorative Dentistry and Endodontics
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• v.15 no.1
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• pp.81-87
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• 1990

The purpose of this study was to evaluate the apical seal produced by low temperature($70^{\circ}C$) injection gutta percha technique(ULTRAFIL) with & without sealer, warm latero-vertical cindensation technique (ENDOTEC) with & without sealer, and the lateral condensation technique with sealer. 100 extracted, single rooted human teeth were divided into 5 groups and root canals were enlarged & obturated according to the purpose of this study. Obturated teeth were immersed in 2.5% methylene blue for 48hrs. at $37^{\circ}C$ incubator and split. The apical sealing ability was evaluated by measuring the degree of dye penetration into the canal. The results were as follows: 1. All group showed varying depth of dye penetration. 2. There were no significant difference among Group I (lateral condensation), Group II (ULTRAFIL with sealer) & Group IV (ENDOTEC with sealer) (P>0.05). 3. There were less dye penetration when used in conjunction with sealer (P<0.001).

• Journal of the Korea Institute of Building Construction
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• v.6 no.1 s.19
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• pp.87-91
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• 2006

Since water leakage and cracks are not the source of serious problems such as long-term lowering of performance and durability of a stricture, including damages to operating facilities of a structure, damages to internal finishing materials, exhibition, and goods, and pollution of residential environment, they might have led to development of positive coping skills; however, an instant loss of lives or property due to earthquake, explosion, typhoon, or a fire was indeed neglected. In these days, repair materials for leakage cannot help but being taken in temporary way without any noticeable countermeasure. This kind of repair is socially criticized many times that is defective construction even if this costs a lot. It was not arrange the standard for construction methods of sealer of injection type for leakage maintenance, even it has been used various type of construction methods for leakage part. In conclusion, we suggest that the construction methods of sealer of injection type for leakage maintenance for leakage to establish the leakage repairing technology as increase of structure demand. Therefore, it would be possible to provide a stage-by-stage solution by developing systematic research activities among the industry, schools, and research institutes to spread maintenance management techniques globally through technical solution to water leakage and cracks, acquisition of structural safety with prolonged durability for life cycle, reduction of water leakage repair expense s, and so on.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2005.11a
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• pp.51-54
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• 2005

The concrete structure hasn't perfect waterproofing performance but if it doesn't have a joint part that could isolate a permeability. Concrete structure(communication tunnel and underground structure) has an expansion joint and construction joint. There are a lot of joint type after construction or expansion, shrinkage, vibration, over load, performance of decline etc.. they offer a water of way by variety change. In this reason, It carries in effect a waterproofing work for the concrete structure of waterproofing. but the structure has a behavior that cause a problem by waterproofing layer of damage, heaving phenomenon, temperature of shrinkage. In this study, we will estimate a field of application for Sealer of injection type for leakage maintenance of construction standard on the waterproofing performance.

• Restorative Dentistry and Endodontics
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• v.15 no.2
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• pp.104-114
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• 1990

The purpose of this study was to evaluate the adaptation of root canal filling material to the dentinal wall of root canal and to compare the sealing ability of the root canal filling materials using ultrasonic endodontic instrument with injection-molded thermoplasticized gutta-percha filling method and lateral condensation method. Fifty fresh human single root exlracted for orthodontic treatment, were randomly selected, and instrumented by step-back technique. And then, the teeth were divided into 5 groups according to each root canal filling methods. In the experimental group 1 and group 2, the root canals were filled with gutta perdia cases using ultrasonic instrument with and without sealer. In the experimental group 3 and 4, using jection-moldeed thermoplasticized gutta-percha method by obtul$^{(R)}$ canals were filled with and without sealer. In the control group, the canals were filled with sealer by lateral candensation. And then, 5 teeth of each group were immersed in black Indian ink, decalcified and cleared. The depth of dye penetration into the root canal were evaluated with stereoscope (Reichert Ltd., USA). Among the 5 teeth remaining in each group, the single longituding grooves were made on the labial and lingual root surfaces and then immersed in the liquid nitrogen to fracture the teeth spontaneously without any distortions of gutta-percha. Each specimens were examined with X-650 Scanning Electron Microscope(Hitachi ltd, Japan) to show the adaptation to the canal wall, void, homogenicity of filling material and location of gutta-percha or sealer in the dentinal tubules of the root canal. The observations were as follows : 1. The experimental group 1 showed smaller mean dye penetration than control group, and showed the penetraton of sealer in the dentinal tubules of apical third of the root canal. 2. The experimental group 2 and group 4 showed the penetration of gutta-percha in the dentinal tubules of root canals. 3. The experimental group 1 and group 3 showed less mean dye penetration than the experimental group 2 and group 4. 4. The experimental group 1 and group 2 showed better adaptation of filling materials than control group.

• Restorative Dentistry and Endodontics
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• v.17 no.2
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• pp.343-354
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• 1992

The purpose of this study was to analyze the relationship between linear and volumetric measurements of apical dye penetration in canals obturated by various kinds of methods. The canals of 108 roots without crown were conventionally prepared and randomly assigned to four group. The canals of group I a2 were obturated by lateral condensation with sealer, group II a2 by thermoplasticized low-temperature ($70^{\circ}C$) gutta-percha with sealer, group III by Thermafil endodntic obturation with sealer and group IV by injection-molded thermop-lasticized guttapercha One mm of root apex was exposed to a 2 % methylene blue solution at $7^{\circ}C$or 10 days, and the quality of apical seals was assessed by measuring the leakage linearly and volumetrically. The obtained results were as follows: In linear measurements, group II showed significanty less leakage than group III, I and group III also showed less than group N, but no statistically significant difference was demonstrated between the others. In volumetric measurements, group II showed significantly less leakage than group I and II, and no significant differnce from group III. There was a weak significant correlation between the linear measurement and the volumetric measurement(r=0.3391, P<0.001).

• Journal of Dental Rehabilitation and Applied Science
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• v.40 no.1
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• pp.1-12
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• 2024

Purpose: To histologically evaluate the effects of three calcium silicate-based sealers on rat mandible tissue. Materials and Methods: Rats were randomly divided as follows: A group that sacrificed immediately after cavity preparation, a group that sacrificed two weeks after cavity preparation, a group that sacrificed two weeks after CeraSeal (CS), AH Plus Bioceramic (AHB), or One-Fil (OF) sealer injection, respectively. After tissue processing for all groups, the bone tissue area (%) and the number of osteoclasts in and around the cavity were measured under a microscope. The results of each group were compared and statistical analysis was performed using one-way ANOVA and Tukey's test. Results: The formation of bone tissue and the presence of osteoclasts in the cavity were observed in the group that sacrificed two weeks after cavity preparation and the group sacrificed two weeks after AHB sealer injection, and these groups showed significantly higher average bone tissue area (%) than the other groups. In the other groups, no inflammation or foreign body reaction occurred in the cavity, and no osteoclasts were observed. Conclusion: All calcium silicate-based sealers used in this study showed a favorable bone tissue response when injected into the rat mandible. In particular, higher bone formation in the cavity was observed in AHB.

• The korean journal of orthodontics
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• v.20 no.3 s.32
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• pp.447-462
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• 1990

The objective of this experiment is to observe structural differences in the othodontic movement of vital (control group) and devitalized (experimental group) teeth in the mongrel dogs. The 5 utilized dogs in this experiment were approximately 1 year of age and their average weight was about 12 Kg. Endodontic therapy was performed on the 2nd premolars in upper & lower jaws of each animal under the general anesthesia by intravascular injection of 25mg/kg of pentobarbital sodium. The canals of the teeth were obturated by using gutta percha in conjunction with root canal sealer (AH26 Densply). One of the roots in the 2nd premolars was hemisected to make an extraction space for the devitalized teeth to be moved. The edgewise technique was employed for the movement of the teeth. Orthodontic models and intraoral roentgenograms were taken before and after orthodontic tooth movement. The open coil springs (.010 x .040) were used at interbraket space in order to provide equal forces (75gm) between the teeth in each arch wire. After 13 weeks of active orthodontic tooth movement, dogs were sacrified and the experimental results w ere examined through the intraoral radiography, microscopic examination and scanning electromicroscopic examination at the root sulfate. From the results of the study, the following conclusions may be drawn: The root resolution and cemental deposition were observed within the pressure and tension site in both group. 2. The root resorbed lacunae were observed in the cementum and/or into the dentin in both group. 3. The prominent osteoblastic activities were observed on the alveolar margin in the tension site in both group. 4. A few of blood vessels were observed in the pressure site, but also lots of blood vessels were observed in the tension site especially in the periphery of the alveolar bone in both group. 5. In the pressure site, resorbed lacunae were formed with deep and narrow cavity in the control group; the shallow and wide cavity in the experimental group. 6. In the pressure site, the repaired cementum or cementoid tissue was lined on cementum in the experimental group, but not in the control group. 7. There was no significant difference between external root resolution of endodontically and vital teeth when both were subjected to orthodontic forces.