• Journal of Technologic Dentistry
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• v.18 no.1
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• pp.117-127
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• 1996

This study was aimed to help the construction of esthetic dental prosthesis by investigation of the factors affecting on the atterition position and attrition angle of maxillary lateral incisors. Therefore 197 complete cast of maxillary and mandibualar extracted form the student of K. college were subjected for this study, and result throught the study are as follows. 1. None attrite rate of the maxiilary right lateral incisors was about 16.2% and that of the maxillary left lateral incisors was about 32.4% of examined teeth. 2. Throught mesiodistal attrition area 1) It showed that right lateral incisors was the most frequence in attrition of mesial area of incisal edge, and left lateral incisors was the most frequence in attrition of mesial and mid area of incisal edge. 2) It showed that square type arch was more frequence in attrition of all incisal edge, and ovoid type arch was more frequence in the attrition of mid area of incisal edge, and ovoid type arch was more frequence in the attrition of mid area of incisal edge, and taper type arch was more frequence in the attrition of mesial area of incisal edge than it of average frequence of right lateral incisors, by dental arch type. 3) It showed that square type arch was more frequence in the attrition of all area and mid area of incisal edge, and ovoid type arch was more frequence in the attrition of mid area of incisal edge, and taper type arch was more frequence in the attrition of mesial and distal area of incisal edge than it of average frequence of left lateral incisal, by dental arch type. 4) Sex, vertical overlap, horizontal overlap, incisal guide angle, did not affect significantly to throughout mesiodistal attrition, statistically 3. Throughout labiolingual attrition quantity. 1) It showed that throughout labiolingual attrition quantity was more attrition in order of taper type arch < ovoid type arch < square type arch, by dental arch type. 2) It showed that throughout labiolingual attrition qauntity was more attrition when the length of horizontal overlap is shorter than it of other, by horizontal overlap. 3) Throughout labiolingual attrition quantity of right lateral incisors showed that male was more attrition than it of female. 4) Vertical overlap, incisal guide angle, sex on left lateral incisors did not affect significantly to throughout labiolingual attrition, statistically. 4. Attrition angle 1) It showed that average attrition anlge of right lateral incisors were $30{\pm}13.02$ degree, and it of left lateral incisors were $26{\pm}13.37$ degree. 2) It showed that taper type arch have a bigger attrition angle than it of average of lateral incisors, and square tape arch have a smaller attrition angle than it of average of lateral incisors, by dental arch type. 3) It showed that horizontal overlap of 2.1mm above have a bigger attrition angle than it of average, by horizontal overlap. 4) It showed that female have a bigger attrition angle it of male, by sex.

• Journal of Technologic Dentistry
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• v.19 no.1
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• pp.121-130
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• 1997

This study was aimed to help the construction of naturally dental prosthesis by investigation of the factors affecting on the attrition position and attrition angle of maxillary canines. Therefore 163 complete cast of maxillary and mandibular extracted from the student of K. college were subjected for this study, and result through the study are as follows. 1. None attrite rate of the maxillary canine was 7%, of examined teeth. 2. Throughout mesiodistal attrition of 1) Throughout mesiodistal attrition area of the maxillary canines showed that mesial area and mid area of cusp was more frequence in attrition than distal area of it. 2) Sex, dental arch type, vertical overlap, horizontal overlap, did not affect significantly to throughtout mesiodistal attrition statistically 3. Througout labiolingual attrition area 1) Throughout labiolingual attrition area of the maxillary canines showed that attrition of the from lingual to labioncisal edge was more frequence than it of linguoincisal edge 2) It showed that attrition of the from lingual to labioincisal edge was more frequence when the length of horizontal overlap is shorter, by horizontal overlap 3) The attrition of the from lingual to labioincisal edge in maxillary left canines showed that male was more frequence in attrition than female. 4) Dental arch type, vertical overlap, did not affect signioficantly to labiolingual attrition, statistically. 4. Attrition angle 1) It showed that average attrition angle of the maxillary right canines were $19{\pm}11.02$ dagree, and it of left canines were $18{\pm}11.83$ degree. 2) It showed that famale have a bigger attrition angle than male, by sex. 3) It showed that attrition angle was bigger when the length of horizontal ovelap is bigger, by horizontal overlap.

• Journal of Technologic Dentistry
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• v.42 no.4
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• pp.313-320
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• 2020

Purpose: The purpose of this study is to compare and analyze the accuracy of single crowns based on the type of occlusal surface. Methods: A single crown wax pattern was fabricated in three types of occlusal surface. The prepared wax pattern was replicated with silicone, and stone was injected to create a stone model. The prepared specimens were scanned using a model scanner. Scans were classified into three groups, and each scan was performed six times to analyze the trueness and precision of a single crown. In addition, only the occlusal surface area was analyzed for trueness and precision. Data were analyzed using the Kruskal-Wallis H test, a nonparametric test (α=0.05). Results: With regard to the trueness value of the occlusal scan area, the no occlusal tooth attrition (NA) group showed the largest error of 3.5 ㎛, and the complete occlusal tooth attrition (CA) group showed the lowest value of 3.1 ㎛. The NA group had the greatest precision, and the medium occlusal tooth attrition (MA) group and CA group showed a low precision value of 3.2 ㎛; the difference between the groups was statistically significant (α=0.05). In the color difference map, the CA group showed a lower error than the NA group. Conclusion: The occlusal surface with severe attrition had excellent accuracy, but the accuracy of the group without attrition was low. There were significant differences between groups, but clinically acceptable values were shown.

• The Journal of the Korean dental association
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• v.10 no.7
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• pp.445-450
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• 1972

The author collected 93 male stone model and 93 female stone model of upper and lower jaw of the koreans as samples and studied the degree of attrition with age increase. Determining the degree of attrition, each normal cusp were given 40 points and calibrated into percentage. The percentage score were examined and analized, and came to the following conclusions. 1) Increased age were found graudually higher the degree of attrition at 10 to 20 age,. The degree of attrition presented localized disappearance of marginal-ridges and marginal grooves. At 30 up to 40 age, about 40 to 50% of the degree of attrition were found gradually on cusp ridges and grooves At 50 to 60 age, it was found about 70 to 80% of attrition. 2) Male score was slightly higher than female. 3) There was no significant difference between male and female score.

• Journal of Oral Medicine and Pain
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• v.32 no.4
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• pp.431-439
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• 2007

This study was performed to investigate the dental ages of the patients with temporomandibular disorders(TMD), using a method of age estimation by dental attrition, and to compare the differences of dental ages between control and experimental groups. In addition, they were compared according to oral habit. Clinical evaluations for the tooth attrition were to examine the study models of 65 TMD patients (mean age of 26.6 years, aged 18 to 40) had visited to the Department of Oral Medicine and Orofacial Pain Clinic, Dental Hospital, Dankook University as a experimental group and 22 volunteers (mean age of 25.4 years, aged 23 to 36) without TMD as a control group. Age differences were calculated subtracting real age from estimated age. Age differences between experimental and control groups were compared statistically between groups classified according to oral habit. As a results, dental age was increased significantly in TMD patients compared with normal subjects. Oral parafunctions which increased dental age were bruxism, clenching and heavy chewing in order. Conclusively, it should be consider that there can be much discrepancy between real age and age estimated by dental attrition in patients with TMD. In addition, it is suggested that dentists should try to protect the tooth from attrition by various parafunction on treating the patients with TMD.

• The Journal of the Korean dental association
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• v.15 no.12
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• pp.983-986
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• 1977

• Journal of Technologic Dentistry
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• v.23 no.1
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• pp.9-19
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• 2001

Microstructure and phase transformation of Ti-Ni-Cu alloy powders produced by using attrition milling method were studied. Mixed powders of Ti-(50-X)Ni-XCu ($X=0{\sim}20$ at%) in composition range were mechanically alloyed for maximum 20 hours by using SUS 1/4" ball in argon atmosphere. Ball to powder ratio was 50: 1 and impeller speed was 350rpm. Mechanically alloyed with attrition millimg method. powder was heat treated at the temperature up to $850^{\circ}C$ for 1 hour in the $10^{-6}$ torr vacuum. Ti-Ni-Cu alloy powders have been fabricated by attrition milling method. and then phase transformation behaviours and microstructual properties of the alloy powders were investigated to assist in improving the the high damping capacity of Ti-Ni-Cu shape memory alloy powders. The results obtained are as follows: 1. After heat treating of fully mechanically alloyed powder at $850^{\circ}C$ for 1hour. most of the B2 and B 19' phases was formed and $TiNi_3$ were coexisted. 2. The B 19' martensite were formed in Ti-Ni-Cu alloy powders whose Cu-content is less than 5a/o. where as the B19 martensite in those whose Cu-content is more than 10at%. 3. The powders of as-milled Ti-Ni-Cu alloys whose Cu-contents is less than 5at% are amorphous. whereas those of as-milled Ti-Ni-Cu alloys whose Cu-content is more than 10at% are crystalline. This means that Cu addition tends to suppress amorphization of Ti-Ni alloy powders.

• The Journal of the Korean dental association
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• v.41 no.1 s.404
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• pp.48-53
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• 2003

The purpose of this study is to report a clinical case of a patient whose vertical dimension of occlusion was lost. There are many reasons for the loss of vertical dimension and one of those can be a tooth wear problem. Thus in this article we will review shortly types of tooth wear: attrition, abrasion, and erosior. And layour the basic philosophy and principles in regaining the esthetics and function of a patient's oral condition with a history of psychological wear, through full mouth restorations.

• Journal of Dental Rehabilitation and Applied Science
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• v.32 no.3
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• pp.224-231
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• 2016

Severe dental attrition causes pathological changes of the tooth, imbalanced occlusion, and functional and aesthetic complications and can also result in a decrease in occlusal vertical dimension that can incur temporomandibular joint and muscular complications. Before restoring the vertical dimension with full-mouth prosthetic restorations, it is important to determine the amount of vertical lifting through complete diagnosis. In this study, a 59 year-old male patient with generalized attrition and fracture of teeth was treated with full-mouth zirconia prosthetic restoration in order to recover vertical dimension and aesthetics. Through the analysis of physiologic rest position and inter-canine distance, the treatment was planned for lifting 3 mm in vertical dimension. Interim crown were fabricated after full-mouth wax up, having the patient use for 6 months. The final monolithic and bilayered zirconia restorations were completed. The patient showed satisfaction in function and aesthetics for 18 months of follow-up since delivering the final restorations.

• Journal of Korean society of Dental Hygiene
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• v.22 no.4
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• pp.225-230
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• 2022

Objectives: Patients with excessive tooth wear should first be diagnosed for the etiology of the tooth wear. Causes of tooth wear include bruxism, clenching, and taking medications for systemic diseases. After identifying the cause of tooth attrition, the final prosthesis should be restored with an appropriate vertical dimension. Methods: A 79-year-old man with worn out teeth desired a whole dental treatment. He was on medications for high blood pressure and asthma. The treatment proceeded with a consultation with a medical doctor. The medications for asthma evoked multiple teeth wear and a loss of the vertical dimension. After recovery of 3 mm of vertical dimension, 2 months of evaluation was followed by an interim prosthesis. Results: The increased vertical dimension caused no problem in function and esthetics, and the final restoration was performed with a full monolithic zirconia crown. Group function, adequate anterior guidance, and the occlusal plane were determined. Conclusions: After the final restoration, the patient was both esthetically and functionally satisfied, and a night guard splint was delivered to prevent prosthesis fracture. The patient was informed about the potential tooth wear associated with asthma drugs and educated to visit the clinic regularly.