PURPOSE: The effects of magnetostrictive and piezoelectric devices on tooth surfaces seem to differ with regard to the root surface roughness they produce. This study aimed to compare the results of scaling using magnetostrictive and piezoelectric devices on extracted teeth. METHODS: Forty-four human extracted teeth were assigned to four study groups (n=11). In two groups (C100 and C200), the teeth were scaled using a magnetostrictive device and two different lateral forces: 100 g and 200 g, respectively. In the other two groups (P100 and P200), the teeth were scaled with a piezoelectric device with 100 g and 200 g of lateral force, respectively. he teeth were scaled and the data on the duration of scaling and the amount of surface were collected and analyzed using the t-test. RESULTS: The mean time needed for instrumentation for the piezoelectric and magnetostrictive devices was 50:54 and 41:10, respectively, but their difference was not statistically significant (P=0.171). For root surface roughness, we only found a statistically significantly poorer result for the C200 group in comparison to the P200 group (P=0.033). CONCLUSIONS: This study revealed that applying a piezoelectric scaler with 200 g of lateral force leaves smoother surfaces than a magnetostrictive device with the same lateral force.
Dental Calculus ; Dental Scaling ; Humans ; Tooth ; Tooth Extraction ; Ultrasonics

This study is based on the result of oral examination of 'A' airliner employees in the period of June 1997 and December 1997. The purpose of this study is to analyze the distribution of dental diseases among workers and the relationship between income level and dental healthiness. Based on the above analysis, this study further tries to indirectly evaluate the method of prophylaxis. Following is the list of basic findings of this study: Firstly, it was found that male workers tend to have inferior dental condition compared with female workers. Also, dental condition of technicians was found to be worse than that of office workers. Secondly, it was found that dental caries decreased with the age. However, periodontal disease was increasing with the age. Therefore, this result leads us to convince that the education should be focused on 'how to brush your teeth' in order to prevent periodontal diseases. Thirdly, more than 40% of the examined were found to be carrying dental calculus related diseases (67.2%) and cervical abrasion (40.5%), respectively. In conclusion, we became to know that the treatment of cervical abrasion and dental calculus at the Dental Clinic is effective in helping 'A' Airliner employees to have better dental status.
Calculi ; Dental Calculus ; Dental Caries ; Dental Clinics ; Diagnosis, Oral* ; Education ; Female ; Humans ; Male ; Periodontal Diseases ; Stomatognathic Diseases

For the purpose of ascertaining the status of physical growth and health status of the University students, a intensive survey was conducted by the authors towards a total of 2,638(male; 2,228, female;410) who passed the written entrance examination at the Seoul National University. The items included the measurements on physical growth, various physical indexes, visual acuity, tuberculosis and dental status. The findings and results can be summarized as follows : 1. Physical Growth. No signigicant difference was found in the physical growth between classes(literature and science) and by ages. In males, the means of body height, body weight, chest-girth and sitting height were 168.0+/-5.07cm, 55.7+/-5.71kg, 85.8+/-4.4cm and 91.5+/-2.21cm, respectively. In females, these were 157.4+/-4.57cm, 00.4+/-5.75kg, 80.3+/-4.51cm and 86.1+/-3.30cm, respectively. Basing on the above measurements several physical indexes were calculated as follows ; Relative body weigh 33.15 in males and 32.02 in females. Relative chest-girth 51.07 and 51.01, relative sitting-height 54.46 and 54.70 Rohrer index 1.00 and 1.02, Kaup index 1.97 and 2.04, Vervaeck index 83.63 and 83.03, and Pelidisi index 89.94 and 92.45. 2. Visual Acuity. Among the students of science classes those of 0.8 and below in vision on left and right occupied 46.4% and 45.0%, those of 0.6 and below 39.1% and 41.2%, respectively. Among the students of literature classes those of 0.8 and below occupied 46.3% and 42.9%, and those of 0.6 and below occupied 41.4% and 39.0, respectively. In males those of 0.8 and below occupied 46.8% and 44.5% and 0.6 and below occupied 41.9% and 39.7%, while in females 0.8 and below occupied 43.9%, and 42.4%, and 0.6 and below occupied 38.3%% and 37.3%, respectively. In males those of 0.8 and below in corrected vision occupied 12.1% and 10.3%, while in females 12.9% and 12.2%, respectively. More students of abnormal vision were found among science classes and the proportions of corrected vision were 38.9% and 37.4% in males, and 33.9% and 33.2% in females, respectively. 3. Tuberculosis. Among the total, 55 students were diagnosed as tuberculosis, of whom 50 were minimal cases, 2 were moderately advanced cases and 3 were far advanced cases. 4. Dental Status. Among the total, 81.2% were of decayed teeth, 20.8% filled, 9.5% missed, 5.0% extraction needed, 9.1% sunplatinum bridges, 3.3% golden bridges and 5.5% golden inaly. Regarding tartar on teeth moderate, heavy and light grades occupied 49.5%, 29.7% and 20.3%, respectively and 0.8% had none. 5. Comprehensive evaluation. According to the criteria 4 grades were applied to comprehensive evaluation as follows : A---excellent in physical status B---with some physical defects but no difficulties in study C---need treatment D---need treatment and rest. Out of the total, A grade occupied 21.6%, B 76.2% and C. and D 2. 2.
Body Height ; Body Weight ; Dental Calculus ; Female ; Humans ; Male ; Seoul ; Tooth ; Tuberculosis ; Visual Acuity

This study was attempted to investigate changes in physiochemical properties of the preparation of saccharification kochujang with retrogradated cooked rice, bread, rice cake and sensory evaluation during 60days aging. 1. Moisture content in 4 samples were slowly increased and pH of kochujang was slowly decreased during aging. 2. Reducing sugar content were about 1.4~2 times higer than T3 and T2 at 50days of aging. 3. In no significant difference 4 samples, the level of adipic acid, citric acid, malic acid was the most and that of acetic acid, iso-butyric acid, fumaric acid, lactic acid, tartaric acid was smaller. 4. Sensory evaluation conducted by fifteen university students as panelist showed that their were more significant difference among four samples and notable preferance for T3 over T0, T1, T2.
Acetic Acid ; Aging* ; Bread ; Citric Acid ; Dental Calculus ; Humans ; Hydrogen-Ion Concentration ; Lactic Acid ; Starch*

PURPOSE: 99mTc-HMPAO is a radiopharmaceutical for imaging cerebral blood flow. HMPAO (RR, SS)-4,8- diaza-3,6,6,9-tetramethylundecan-2,10- dione bisoxime) has three stereoismers such as, meso-, d-, and l-HMPAO. Techentium complexes of meso-HMPAO and d,l-HMPAO are known to have different in vivo brain uptakes. In this study, enantiomers of HMPAO (d-HMPAO and l-HMPAO) were separated from d,l-HMPAO. These enantiomers were labeled with 99mTc and the biodistribution studies were performed in mice. MATERIALS AND METHODS: An intermediate imine product was produced from 2,3-butanedione monooxime and 2,2-dimethyl- 1,3-propanediamine (54% yield) and was reduced into a mixture of three isomers (35% yield). The meso-isomer was separated from d,l-mixture by repeated fractional crystallization (11% yield). The d- and l-enantiomers were subsequently separated by co-crystallization with optical isomers of tartaric acid (25% and 5% yield, respectively). Each enantiomeric HMPAO was labeled with 99mTc by reacting with SnCl2 2H2O and 99mTc-pertechnetate. Biodistribution study was performed 1 hr after tail vein injection to ICR mice. RESULTS: Radiochemical purities of each compound were over 80%. In biodistribution study, the brain uptakes of d,l- d- and l-form were 1.34, 1.12 and 1.67% ID/g, respectively. In case of l-Isomer the brain uptake was higher (1.5 fold) than d-isomer. CONCLUSION: We successfully purified each enantiomeric HMPAO. In biodistribution study of stereoismers of 99mTc-HMPAO in mice, l-HMPAO may show better brain image than d,l-HMPAO which was supplied in a commercial kit.
Animals ; Brain* ; Crystallization ; Dental Calculus ; Diacetyl ; Mice ; Mice, Inbred ICR ; Stereoisomerism ; Technetium Tc 99m Exametazime* ; Veins

Fresh dental calculus were scratched and rinsed with distilled water, and then dissolved by HNO3. Simulated body fluid was used as control. Aqueous ammonia was added to step up the pH. FSEM and FI-IR were used to analyze the crystal character of deposition. Turbid occurred when pH = 5.4 and deposition occurred when pH = 5.6. Ribbon-like crystal, which was the same as the crystal in natural dental calculus was observed in experimental group and was evidenced to be hydroxyapatite (HAP) by FT-IR. HAP formation through homogeneous phase redeposition of dissolved dental subgingival calculus may be related with the existing template molecules in dental subgingival calculus resolution, which induce the biomineralization of HAP formation.
Calcinosis ; pathology ; Calcium Phosphates ; chemistry ; Crystallography ; Dental Calculus ; chemistry ; Dental Plaque ; chemistry ; Gingival Diseases ; etiology ; Humans ; Hydroxyapatites ; chemistry

The purpose of this study was to develop effective dental hygiene chews for cats based on the anatomical features of the dentition and patterns of chewing motion. All cats were volunteered for dental prophylaxis followed by dental impressions using yellow stone and alginate under general anesthesia. Twenty parameters related to dentition were defined in order to compare dental impressions using digital caliper. For the chewing motion study, patterns of chewing motion were identified based on recordings made with a digital camera. Ten cats (4 domestic shorthairs, 2 Russian blues, 1 American shorthair, 1 Persian, 1 Turkish Angora, and 1 Devon Rex) were recruited for the study. The parameters related to teeth and oral size were similar among the studied cats. Chewing motion can be described as more of a guillotine-like motion rather than a crushing motion, with cats chewing 3–7 times before swallowing. The chewing pattern of cats involves shearing for a short period of time followed by immediate swallowing. Therefore, the overall size of the dental hygiene chew could be determined based on the measurement of the oral size for inducing chewing. The surface details of the dental hygiene chew could be designed for prevention and removal of dental calculus and plaque in cats considering the anatomical teeth parameters. Dental hygiene chews customized for cats considering the different anatomical features of their teeth might be effective for oral care.
Anesthesia, General ; Animals ; Cats ; Deglutition ; Dental Calculus ; Dental Prophylaxis ; Dentition ; Gingiva ; Mastication ; Oral Hygiene ; Periodontal Diseases ; Tooth

OBJECTIVES: This study aimed to investigate factors related to the periodontal health of 12-year-old children.METHODS: In 2015, the Korean Children's Oral Health Survey from the Ministry of Health & Social Welfare conducted a nationwide representative sample comprised of 23,702 12-year-old children. The calibration-trained dentists examined the gingivitis and dental calculus of the children taking into consideration of the Löe and Silness gingival index to diagnose gingivitis with a modified gingivitis scale. We used questionnaires to collect data from the children on dental treatments, the experience of dental pain and gingival bleeding, self-perceived oral health, and oral health behaviors. Data were analyzed using a complex samples Chi-square test, general linear model, and logistic regression. Significance was determined at P < 0.05.RESULTS: The prevalence of gingivitis was higher among males (OR 1.57), among children with poor perception (OR 1.19), dental calculus (OR 3.68), or gingival bleeding experience (OR 2.00), and among children not using dental floss (OR 1.69) or tongue cleaner (OR 1.90). The prevalence of dental calculus was higher among children with gingivitis (OR 3.82) and among children who had not visited a dental clinic in the preceding year (OR 1.31). However, dental calculus was lower among children with a higher frequency of daily toothbrushing (OR 0.75), intake of cariogenic foods (OR 0.90), or a higher DMFT index (OR 0.91).CONCLUSIONS: Children with dental calculus and gingival bleeding who did not visit a dental clinic in the preceding year also had a higher prevalence of gingivitis and dental calculus. The prevalence of children's dental calculus was lower among children with a high frequency of daily toothbrushing.
Child ; Dental Calculus ; Dental Clinics ; Dental Devices, Home Care ; Dentists ; Gingivitis ; Hemorrhage ; Humans ; Linear Models ; Logistic Models ; Male ; Oral Health ; Periodontal Index ; Prevalence ; Social Welfare ; Tongue ; Toothbrushing

OBJECTIVETo describe the periodontal condition of population in Qinghai province and provide basic data for the diseases prevention.

METHODSReferring to the guideline for the third national oral health survey, the method of multistage, stratified, equal capacity, simple random sampling was carried out in population of 12, 35-44, and 65-74 years old in Qinghai province. Gingival bleeding, calculus, periodontal pocket and loss of attachment of population were investigated.

RESULTS1) In 12, 35-44, 65-74 age groups, the prevalence of gingival bleeding was 98.74%, 97.84%, 92.23%, the prevalence of calculus was 89.76%, 99.87%, 92.87%. 2) In 35-44 age group, the prevalence of shallow periodontal pocket was 34.64%, the prevalence of deep periodontal pocket was 5.58%. In 65-74 age group, the prevalence of shallow periodontal pocket was 50.45%, the prevalence of deep periodontal pocket was 13.12%. 3) In 35-44 age group, the prevalence of 4-5, 6-8, 9-11, 12 mm or more loss of attachment was 40.74%, 18.78%, 4.82%, 1.78%. In 65-74 age group, the prevalence of 4-5, 6-8, 9-11, 12 mm or more loss of attachment was 71.21%, 51.34%, 20.51%, 7.01%.

CONCLUSIONThe oral health condition of population in Qinghai province is very poor. The periodontal pocket and loss of attachment was severely. The disease prevention should be strengthen in Qinghai province.

Adult ; Dental Calculus ; Dental Health Surveys ; Female ; Gingival Hemorrhage ; Humans ; Middle Aged ; Periodontal Attachment Loss ; Periodontal Diseases ; Periodontal Index ; Periodontal Pocket ; Prevalence

OBJECTIVETo provide basic data for the prevention of oral diseases in minorities by investigating the oral health status and behavior related to oral health knowledge of individuals aged 35 to 44 years in Dongxiang, Bonan, and Yugur.

METHODSThe caries and periodontal health of 445 individuals aged 35 to 44 years were examined according to the method and criterion prescribed by the World Health Organization and the Third National Oral Health Epidemiologic Investigation. A questionnaire survey on related oral health knowledge and behavior was conducted.

RESULTSThe crown caries prevalence rate in Dongxiang, Baoan, and Yugur were 48.28%, 79.47%, and 67.11%, respectively; the root caries prevalence rates were 38.62%, 69.54%, and 42.95%, respectively. The rates of gum bleeding in Dongxiang, Bonan, and Yugur were 86.90%, 90.07%, and 65.77%, respectively. The rates of dental calculus in Dongxiang, Bonan, and Yugur were 99.31%, 100.00%, 99.33%, respectively, and the rates of periodontal bags were 68.97%, 67.55%, and 43.62%, respectively. Only 69.84% of the respondents brush their teeth every day; 94.90% of the respondents do not floss. Only 20.19% of the respondents contact a doctor for a toothache, and 42.23% of the respondents have never seen a dentist.

CONCLUSIONCaries morbidity is high among the respondents aged 35 to 44 years from Dongxiang, Bonan, and Yugur. The periodontal health status and oral hygiene of the respondents are poor, and behavior related to oral health knowledge is insufficient. Thus, more attention must be provided to the prevention and control of caries and periodontal diseases among middle-aged people in the area.

Adult ; DMF Index ; Dental Calculus ; Dental Caries ; Female ; Health Knowledge, Attitudes, Practice ; Health Status ; Humans ; Male ; Oral Health ; Oral Hygiene ; Periodontal Diseases ; Prevalence