• Journal of the Korea Convergence Society
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• v.12 no.12
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• pp.153-159
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• 2021

The purpose of this study is to determine the demage of tooth surface changes according to exposure time of commercially available green grape juice and pomegranate juice. Extracted healthy human premolar enamel surfaces were used. Control group immersed in phosphate-buffered saline (PBS) and 10 ml of commercially available green grape juice and pomegranate juice applied experimental group was divided into 7 groups. The pH of the experimental juice was measured, and the change and micrographics of the surface were confirmed through a Scanning Electron Microscope (SEM). It was found that the more the immersion time between the tooth surface and acid juice, such as damage to the tooth surface, has a greater effect on the surface damage. Based on the results of this study, it is necessary to reduce the number of drinking times and retention time in the oral cavity.

• Journal of Dental Rehabilitation and Applied Science
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• v.26 no.4
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• pp.455-462
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• 2010

Patients often seek rehabilitative treatment for severely worn dentition. The etiology of noncarious tooth wear due to attrition, abrasion, and erosion is multifactorial. To treat the worn dentition, it is important to identify and eliminate and/or control the factors that contribute to excessive wear. Many situations requiring complete mouth rehabilitation present with the challenge of a lack of restorative space. To establish a correct occlusal plane and space for prostheses, it is necessary to increase vertical dimension. This may require an increase in occlusal vertical dimension. Also clinicians should be able to choose the appropriate restorative materials to achieve excellence in natural esthetics as well as proper biomechanics and durability. This article presents a method for altering occlusal vertical dimension to restore dentitions with limited restorative space due to loss of tooth structure.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.4
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• pp.555-563
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• 2004

The pH of beverages is known to be low and have, therefore, been implicated in the increasing incidence of erosion. Erosion is believed to be the predominant cause of teeth wear in children and young adults, although there will always be a contribution from attrition and abrasion. The aim of the present study was to evaluate the effect of yogurt on the progression of erosive demineralization in human enamel using demineralization model in vitro. In 4 yogurts, available on the market, pH, buffering capacity and the concentrations of calcium, phosphate and fluoride were determined. The buffering effect was determined by titration with NaOH. 50 milliliters of each drink was then titrated with 1M sodium hydroxide, added in 0.5 milliliters increments, until the pH reached about 7. Human deciduous enamel(n=40) samples were divided into four groups and exposed to 80ml of the yogurt for 30,60, 90 and 120min. Enamel surface microhardness(VHN) was examined before and after each exposure. 1. The average PH of fermented milk was 3.77 and this pH value was acidic enough to cause tooth erosion. 2. All of the fermented milks were found to be erosive(p<0.05) 3. The teeth exposed to the fermented milk all showed erosion like lesions and microhardness measurements showed that enamel surface hardness decreased proportionately with increased time of immersion in all tooth specimen groups. 4. After immersion for 30 and 60 minutes, reduction rate of microhardness values was not significantly different between the groups(p>0.05). However, after 90 and 120 minutes, reduction rate of each group was significantly different(p<0.05).

• Journal of dental hygiene science
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• v.12 no.4
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• pp.320-328
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• 2012

The purpose of this study was to evaluate the tooth whitening and properties of an enamel surface after treatments with tooth bleaching agents that contained dicalcium phosphate dihydrate (DCPD) and hydrogen peroxide (HP). Thirty specimens were obtained from fifteen premolar and were randomly divided into three groups (n=10): 1, 3.5% HP + 0 g DCPD; 2, 3.5% HP + 0.1 g DCPD; 3. 3.5% HP + 1 g DCPD. All groups were bleached 8 hours per day for 14 days. With increasing DCPD concentration, the pH values in the agents increased, making it less acidic. However, there was no statistically significant difference (p>.05). As the concentration of DCPD was increased, the concentration of Ca and P was also increased. In all groups, after the tooth whitening, the tooth color was found to have a value of $L^*$ (p<.05). All groups showed significantly decreased enamel microhardness compared to their baseline (p<.05). The percentage microhardness loss (PML) of the group A1 and A2 were significantly lower than that of group A3. The obvious variation of morphology was observed on enamel surfaces in group A1. Following an analysis of the constituents of enamel surface after bleaching, as DCPD content was increased, the amount of Ca and P was increased. In this study, the experimental results suggest that DCPD/HP agent less demineralization changes such as the erosion morphology and hardness loss without compromising whitening efficiency.

• The Journal of Korean Academy of Prosthodontics
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• v.36 no.1
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• pp.133-149
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• 1998

Clinical application of composite resin recently draw great concerns in dentistry. Especially due to advantages such as esthetics, adhesiveness, simple clinical procedures, various shapes and kinds of composite resins are widely being applied to prosthodontics, conservative dentistry, and orthodontics. But, clinical problems attributable to the polymerization shrinkage of composite resin have been proposed, and we have to regard clinical problems such as secondary caries, loss of restoration, fracture of the surrounding tooth structure, marginal discoloration, and tooth sensitivity, and many portions are remained to be overcome. Therefore, this study attempts to analyze stress distribution between resin and tooth structure which is generated during polymerization shrinkage of composite resin using three dimensional finite element method. Three dimensional finite element models with conventional box-shape cavity and erosion/abrasion type V-shape lesion cavity in upper central incisor were developed. These cavities were filled with four different types of placement techniques. (bulk filling, horizontal increment filling, oblique occlusal increment filling, oblique gingival increment filling) The stresses generated by polymerization shrinkage of composite resin were calculated. The results analyzed with three dimensional finite element method were as follows : 1. The increment filling technique showed the highest maximum normal stress in both conventional box-shape and V-shape cavities and showed a tendency to decrease after complete polymerization. 2. The bulk filling technique resulted in increased stresses during the curing process in both conventional box-shape and V-shape cavities and the highest maximum normal stress occurred after complete polymerization. 3. The bulk filling resulted in the lowest maximum normal stress in both box-shape and V-shape cavities 4. Regardless of placement method, in conventional box-shape cavity, the maximum normal stress increased in dentin floor, enamel, dentin sequence and in V-shape cavity, the maximum normal stress increased in enamel, dentin sequence.

• Journal of Dental Rehabilitation and Applied Science
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• v.39 no.4
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• pp.222-228
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• 2023

Attrition is the loss of tooth hard tissue due to contact between teeth, and in severe cases, dentin is exposed, accompanied by selective corrosion and excessive wear of teeth, which is called cupping. If these lesions are left untreated, the size of the lesion gradually increases, breaking the unsupported enamel, resulting in a decrease in aesthetics and chewing function. In this case report, patients with cupping and enamel fracture due to severe attrition were directly restored using a resin with soft properties containing organic fillers. In the follow-up observation six years later, most of the filling of the occlusal surface was eliminated, but the filling on the buccal surfaces remained relatively intact, and it was confirmed that this type of resin was suitable for the area where the occlusal force was relatively weak rather than the area where the occlusal force was greatly applied.

• Korean Journal of Bronchoesophagology
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• v.13 no.1
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• pp.47-50
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• 2007

Foreign bodies of the parapharyngeal space can cause severe complications such as descending suppurative mediastinitis, jugular thrombophlebitis, cavernous sinus thrombosis and carotid erosion. Therefore, early diagnosis and surgical intervention are needed to reduce morbidity and mortality. We present a case of a toothbrush as foreign body in the parapharyngeal space in 28-year-old male patient. The tooth brush was broken and the remnant of that was left in the patient's mouth. Under general anesthesia, intraoral approach was undertaken and successfully the toothbrush was removed, and then incision and drainage was done by transcervical approach. We report this case with review of literature.

• Imaging Science in Dentistry
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• v.49 no.1
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• pp.71-77
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• 2019

Primary intraosseous squamous cell carcinoma is a rare malignant central jaw tumor derived from odontogenic epithelial remnants. Predominantly, it affects mandible, although both jaw bones may be involved. This report describes a 60-year-old man who was initially misdiagnosed with a periapical infection related to the right lower wisdom tooth. After four months, the patient presented to a private dental clinic with a massive swelling at the right side of the mandible. Panoramic radiographs and advanced imaging revealed a lesion with complete erosion of the right ramus, which extended to the orbital floor. A biopsy from the mandibular angle revealed large pleomorphic atypical squamous cells, which is the primary microscopic feature of a poorly differentiated squamous cell carcinoma.

• Journal of dental hygiene science
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• v.17 no.4
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• pp.352-357
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• 2017

Consumption of liquid digestive medicine has continually grown in recent years. This present study was designed to evaluate the capability of liquid digestive medicine to erode dental enamel, relating the pH and titratable acidity of liquid digestive medicine. Three commercially available liquid digestive medicines were chosen these were Gashwalmyeungsu, Saengrokchun and Wicheongsu. The liquid digestive medicines were evaluated in respect to pH, titratable acidity and concentrations of calcium and phosphate, respectively. This measure was carried out three times for each digestive medicine and was recorded the data as mean (standard deviation). Bovine enamel specimens measured microhardness at base line and then were randomly assigned to 4 groups of 10 each. The specimens were immersed into each liquid digestive medicine for 1, 3, 5, 10, 15, and 30 minutes and then evaluated each time by VHN. All digestive medicines had a pH of less than 3.7. Wicheongsu had the lowest pH 2.93 and Gashwalmyeungsu had highest pH 3.63. In pH 5.5, titratable acidity of Wicheongsu was 1.27 ml. Gashwalmyeungsu was 0.63 ml. Saengrokchun was 0.60 ml. All liquid digestive medicines showed low concentration of calcium and phosphate. The microhardness of specimens after immersion into liquid digestive medicines was continuously reduced in all digestive medicines. After 30-minute treatment in liquid digestive medicines, Wicheongsu containing low pH and high tiratable acidity was shown to be lowest microhardness value ($207.80{\pm}15.52$). The three liquid digestive medicines caused surface softening of enamel erosion. We conclude that drinks, commonly consumed by functional dyspepsia patient can cause erosion of enamel.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.3
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• pp.273-279
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• 2016

Severe tooth wear may lead to pathological changes of pulp, imbalance in occlusion as well as functional and esthetic problems. In this case, 34-year-old male came to the hospital because of generally worn dentition due to attrition and erosion. After evaluation, a full mouth restoration with elevation of the vertical dimension of occlusion was planned. After occlusion was stabilized by an occlusal stabilization appliance, centric relation position was recorded and subsequent provisional restorations were fabricated. After evaluation, a CAD-CAM (computer aided design-computer aided manufacturing) prosthetic restoration was carried out using monolithic zirconia. After 12 months of follow up observation, the patient was satisfied with function and esthetic appearance.