• Journal of Oral Medicine and Pain
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• v.6 no.1
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• pp.101-110
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• 1981

For the purpose of an estimation of age based on the changes in the human dental cavity caused by increase in age, 1,208 extracted teeth in the parts from central incisors and lateral incisors and lateral incisors to second premolars of upper and lower, right and left side were evaluated and analized all of surface index of pulp cavity. The results are as follows : 1. The surface index of pulp caxities of upper and lower, central and lateral incisors, and tend to decrease regularly as the age increase. So above teeth are more applicable to age estimation than canine and premolars. 2 For the purpose of age estimation by surface index of pulp cavity of central and lateral incisor, linear equations are as follows. Upper central incisor: X=(16.301-Y)/0.12 Upper lateral incisor: X=(16.620-Y)/0.11 Lower central incisor: X=(20.963-Y)/0.16 X=Age Y=Surface index of pulp cavity Correlation coefficient between chronologic age and estimated age is 0.699 3.The least error(3.3 yrs of age)reveals in 41-45 age group, which shows the highest possibility of estimation of age. The highest error(4.1 yrs of age)reveals in 61-65 age group and 56-60 age group.

• Journal of Oral Medicine and Pain
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• v.18 no.1
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• pp.107-117
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• 1993

The author has taken intraoral standard films by the paralleling technique of 6414 teeth in 838 patients ranged from early twenties to early sixties and analysed the change of pulp cavity in the mandibular posterior teeth by ageing. The obtined results were as follows : 1. There was no significant difference between the right and left teeth. 2. The degree of change of pulp cavity in female was higher than that in male. 3. The change of pulp cavity was increased by ageing. 4. The correlation between the degree of change of pulp cavity inmandibular posterior teeth (X) and age (Y) were : Male 1st premolar Y=13.22X3.37+ r=0.79 2nd premolar Y=12.09X+3.65 r=0.79 1st molar Y=11.90X+1.25 r=0.78 2nd molar Y=10.51X+10.43 r=0.83 Female 1st premolar Y=13.66X-2.49 r=0.86 2nd premolar Y=13.63X-2.42 r=0.86 1st molar Y=12.42X-1.44 r=0.79 2nd molar Y=11.42X+5.91 r=0.84

• The Journal of the Korean dental association
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• v.56 no.10
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• pp.572-580
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• 2018

Adequate access cavity is the key to achieving endodontic success. The aims of the access cavity can be considered as follows: 1) Creation of a smooth unimpeded pathway for instruments to canal orifices 2) Removal of the entire roof of the pulp chamber in order to inspect the pulp floor, 3) Preservation of natural tooth substance consistent with the above. Recently, contracted endodontic cavities based on minimally invasive endodontics has introduced. This has the benefit of preserving the pericervical dentin more than traditional access cavity with achieving long-term success. However, some studies reported controversial results regarding root canal detection, instrumentation efficacy (noninstrumented canal area, hard tissue debris accumulation, canal transportation, and centering ratio) as well as fracture resistance. Therefore, further studies are required for accepting contracted access cavity, and modified form of traditional and contracted access cavity could be considered.

• The Journal of the Korean dental association
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• v.12 no.3
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• pp.195-198
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• 1974

The purpose of this study is to obtain the histopathological change of dentin and pulp when the prepared cavity is exposed to oral fluid without protection. The results were as follows: 1. Hyperemia of pulp blood vessel and round cell infiltration in odontoblast layer observed on the one week experimental dogs. 2. Marked edematous change, round cell infiltration, fibrotic change and prolif eration of collagenous fiber showed on the 8 week experimental dogs. 3. Prepared cavity should be protected by the biologically accepted lining mater ials regardless of cavity depth.

• Restorative Dentistry and Endodontics
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• v.12 no.2
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• pp.27-32
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• 1987

After a vital pulpotomy in human permanent teeth, the responses of the remaining pulp tissue under formocresol was studied histologically. The class I cavity was prepared on the teeth and the pulp was amputated. Formocresol was placed over the amputated tissue and the cavity was sealed with zinc phosphate cement and amalgam. The teeth were extracted after 1, and 3 weeks following the operation and were decalcified, sectioned and stained with hematoxylin and losin. Microscopic examination reveals as follows; I. Healing of the pulp at the amputated site did not occur in the pulps treated with formocresol. 2. At one week the pulps were normal except only slight inflammatory reaction. 3. At three weeks, the pulps showed the most serious inflammation, bleeding and necrotic state.

• Restorative Dentistry and Endodontics
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• v.26 no.5
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• pp.387-392
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• 2001

When cavity floor is near the pulp, polymerization of light-activated restorations results in temperature increase. This temperature increase cause by both the exothermic reaction process and the energy absorbed during irradiation. Therefore instating base is required. Most frequently used insulating base is glass ionmer. The purpose of this study was to evaluate intrapulpal temperature changes of glass ionomer according to various curing intensity and curing time. Caries and restoration-free mandibular molars extracted within three months were prepared Class I cavity of 3$\times$6mm with high speed handpiece. 1mm depth of dentin was evaluated with micrometer in mesial and distal pulp horns. Pulp chambers were filled with 37.0$\pm$0.1$^{\circ}C$ water to CEJ. Chromium-alumina thermocouple was placed in pulp horn for evaluating of temperature changes. glass ionomer material was placed in 2mm. total curing time was 40s: continuous 40s, intermittent 20s, intermittent 10s. Glass ionomer material was cured with 300mW/$\textrm{cm}^2$, 550mW/$\textrm{cm}^2$ light curing unit. The results were as follows : 1. Temperature in pulp increased as curing unit power is increased. 2. Temperature in pulp more increased continuous emission than intermittent emission.

• Journal of the korean academy of Pediatric Dentistry
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• v.25 no.3
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• pp.583-597
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• 1998

The purpose of this study was to evaluate temperature change occurred in enamel, dentin and pulp due to the heat from cavity prepration with laser. We made three models had different cavity depth: cavity depth of model A was 3.52mm, model B was 2.32mm, model C was 1.16mm. We irradiated cavity base with thermal capacity of $30J,100J,300J/cm^2s$ during few seconds and studied the change of temperature in tooth during 10 seconds, and estimated change of thermal capacity by different irradiated site and exposure time. At $300J/cm^2$ irradiation for 2 seconds, the temperature of irradiated surface was elevated fast according to irradiated thermal energy during 1 second. In proportion to continuous exposure time, temperature elevated slowly. The surface temperature was $1370^{\circ}C$. After discontinue of thermal irradiation, the heat of irradiated surface was diffused in dentin and pulp and the greatest temperature was made. The greatest temperature was disappeared within 10 seconds The greatest temperature of the inner part of model brought about very severe change by different depth. Temperature in pulp was raised by the greater irradiated energy density and exposure time.

• Journal of Oral Medicine and Pain
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• v.34 no.2
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• pp.179-188
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• 2009

Aim of this study is to examine correlation between size of the coronal pulp cavity and chronological age in adult. Total 716 teeth (218 mandibular canines, 230 first premolars, 268 second premolars) free from pathologies and dental restorations were selected from 276 patients (111 males, 165 females), ranging from 20-69 years. Using periapical X-ray, the height (mm) of the crown (CH=coronal height) and the height (mm) of the coronal pulp cavity (CPCH=coronal pulp cavity height) of the teeth were measured. The tooth-coronal index (TCI) after Ikeda et al (Jpn. J. For. Med. 1985;39:244-250) was computed for each tooth and regressed on real age. With increasing age, the TCI was relatively decreased, indicating the reduction of length of the pulp chamber. Even reduction of the TCI with aging was found in combined group rather than in each sex and type of tooth separately. The most definite reduction was in canine of combined group. The correlation coefficient was strongest when measurement from canines of females (r2=0.247).

• The Journal of the Korean dental association
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• v.11 no.3
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• pp.185-189
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• 1973

Dental amalgam in the clinic practice of dentistry is one of the most important materials. Mercury, one of the component of this alloy, is emitted in the form of vapor after filling as long as 5 days Silver particles penetrate into the dentine deeply along the tubles underneath cavity floor. To determine the permeability of mercury in the teeth following experiments were performed. Class 5 cavities total 40 from 10 dogs were prepared on upper and lower canines and amalgam alloys which contain about 10uCi of radioactive mercury were inserted. The animals were sacrificed 7 days after the experiments and the teeth were decalcified, sectioned and autoradiographed by means of emulsion and stained by H & E. Following are the results obtained from this experiments. 1. Blackened silver grains were found along the dentinal tubules underneath the cavity floor. Beyond the border of dentine and pulp chamber grains were seen in odontoblastic layer (Fig. 1, 2, 3, 4) 2. Underneath the odontoblastic layer, the pulp tissue showed almost normal appearance except slight dilatation of blood vessel.

• Restorative Dentistry and Endodontics
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• v.21 no.2
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• pp.451-469
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• 1996

The purpose of this study was to investigate the effect of calcium hydroxide and glass ionomer cement fillings on the levels of $LTB_4$ and $LTC_4$ in experimentally inflamed rat dental pulp. The dental pulp in the mandibular incisor of wistar rat was irritated by cutting a 5mm deep hole in the dentin with a twist drill bur of 0.5mm diameter, without cooling. The cavities were filled with calcium hydroxide(light-cured) and glass ionomer cement(light cured). The untreated pulp served as control tissue specimen. After cavity preparations, the rat with or without various treatment were sacrificed in various time by decapitation. The dental pulp tissue were carefully removed and the concentrations of $LTB_4$ and $LTC_4$ were determined by radioimmunoassay. And pulps were examined histologically to observe inflammatory feature. The result were obtained as follows : 1. The inflammatory features of pulps were observed microscopically in all experimental groups. And degree of inflammation was decreased with time. 2. The concentrations of $LTB_4$ and $LTC_4$ for all experimental groups were significantly higher than those for control group 6 hours after cavity preparation(p<0.05). 3. The group filled with calcium hydroxide was the lowest, and the group filled with glass ionomer cement, the group of irritation in that order showed increased concentrations of $LTB_4$ and $LTC_4$ 6 hours after cavity preparation. In the concentrations of $LTB_4$, significant differences among 3 groups were noted(p<0.05). 4. The group filled with calcium hydroxide was the lowest, and the group filled with glass ionomer cement, the group of irritation in that order showed increased concentrations of $LTB_4$ and $LTC_4$ 24 hours after cavity preparation. And there were statistically significant difference in concentrations of $LTB_4$ between the group of irritation and the group filled with calcium hydroxide(p<0.05). 5. The group filled with calcium hydroxide was the lowest, and the group filled with glass ionomer cement, the group of irritation in that order showed increased concentrations of $LTB_4$ and $LTC_4$ 48 hours after cavity preparation. But no statistically difference was found (p>0.05). 6. The concentrations of $LTB_4$ and $LTC_4$ in all experimental groups were highest level at 6 hour after experiment and decreased as time progresses(correlation coefficient>0.8).