Young-Ku Kim

Oral manifestations and salivary flow rate, pH, and buffer capacity in patients with end-stage renal disease undergoing hemodialysis

OBJECTIVE The aim of this study was to investigate oral manifestations and salivary changes in patients with end-stage renal disease undergoing hemodialysis. STUDY DESIGN Eighty-two patients undergoing hemodialysis for renal insufficiency were examined; 22 of these patients were randomly selected for salivary tests. Unstimulated whole saliva and stimulated parotid saliva were collected, and flow rate, pH, and buffer capacity were examined. Twenty-two healthy volunteers were included as controls. RESULTS Uremic odor, dry mouth, and taste change were common symptoms. Petechia and/or ecchymosis and increase of tongue coating were major signs. The flow rates of unstimulated whole and stimulated parotid saliva were decreased in the patient group. The pH and buffer capacity of unstimulated whole saliva were increased in the patient group, but stimulated parotid saliva did not show any significant differences. CONCLUSIONS Patients with end-stage renal disease undergoing hemodialysis showed apparent oral and salivary changes. The results help us understand the relationship between oral changes and renal insufficiency.

Relationships between disk displacement, joint effusion, and degenerative changes of the TMJ in TMD patients based on MRI findings

This study was performed to investigate the relationships between disk displacement, joint effusion, and degenerative changes in patients with temporomandibular disorders using MRI. Randomly selected MRIs of 508 temporomandibular joints of 254 patients (92 males and 162 females, mean age was 30.5±12.0 years) were reviewed retrospectively. Seventy-eight percent (198 out of 254) of the patients complained of joint pain. Compared with joints with a normal disk position, the joints with anterior disk displacement with reduction showed a 2.01 odds ratio (P<0.01) of degenerative changes and a 2.85 odds ratio (P<0.001) of joint effusions. The joints with anterior disk displacement without reduction showed a 4.43 odds ratio (P<0.001) of degenerative changes and a 4.61 odds ratio (P<0.001) of joint effusions. These results clearly show that the risk of degenerative changes and joint effusions increase with displacement of the disk position in patients with temporomandibular disorders. Although all disk displacement situations do not progress to painful joints and/or degenerative joint diseases, the possibility of an increased risk of progression by a breakdown in the balance between a patients adaptive capacity and functional loading of the TMJ should be assessed in each and every patient through comprehensive evaluation of various contributing factors.

Age estimation by occlusal tooth wear

The purpose of the present investigation was to test the accuracy of a new scoring system in recording tooth wear for age estimation. The material consisted of dental stone casts of 383 volunteers who had sound premolars and molars with normal occlusion. The degree of occlusal wear for all premolar and molar teeth was scored with the new system. The high intra- and inter-examiner concordances showed that the new score system was very reliable. The degree of tooth wear showed a significant positive correlation with age in each and every examined tooth of both males and females. Tooth wear scores of males were higher than those of females. Calculating tables for age estimation were designed and the accuracy of age estimation was obtained with the General Linear Models procedures. Our system could provide estimation of an individuals age within +/-3 years in 42.4% of males and 49.4% of females, within +/-5 years in 61.8% of males and 63.3% of females. When the subjects were divided into two age groups and data were re-treated, the accuracy of age estimation was increased. Collectively, it was shown that our new system for scoring tooth wear is a reliable and accurate method for age estimation.

Human dental age estimation using third molar developmental stages: Accuracy of age predictions not using country specific information.

Unquestionable forensic age investigations are based on statistical models constructed on a sample containing subjects of identical origin as the examined individual. In cases where corresponding models are unavailable, the established report has to describe the possible effects of this unrelated information on the predicted age outcome. The aim of this study is to collect country specific databases of third molar development and to verify how the related dental age estimations are influenced if we were to use dental developmental information only from Belgium or from all collected countries together. Data containing third molar developmental stages scored following Gleiser and Hunt (modified by Köhler) were collected from 9 country specific populations (Belgium, China, Japan, Korea, Poland, Thailand, Turkey, Saudi-Arabia and South-India). Age predictions were obtained from a training dataset and validated on a test dataset. Bayes rule using the repeated third molar scores is applied to get age predictions and prediction intervals. Three age predictions were compared for males and females separately. For the first prediction, the training dataset contains only Belgian subjects. For the second prediction, the training dataset for each country consists only of subjects of the country itself. For the final prediction, subjects from all countries are pooled into one common training dataset. Besides the (absolute) difference between the chronological age and the predicted age, specific interest lies in the juvenile-adult distinction. In the age range from 16 to 22 years 6982 subjects (3189 male and 3793 female) were analyzed. Using information on third molar development from Belgium compared to information from the country specific databases hardly increased the mean absolute differences (MAD) and mean squared errors (MSE): the MAD and MSE increased on average with 0.5 and 2.5 months with maximal increases of, respectively 1.6 and 7.3 months. Using information from all countries pooled compared to country specific information provided even on average negligible increases (0.05 and 0.2 months for MAD and MSE, respectively). For the juvenile-adult discrimination, using information from all countries instead of country specific information yielded comparable performances. Using Belgium instead of country specific information increased the percentage of correctly identified juveniles, but decreased the percentage of correctly identified adults. The adult-juvenile discrimination based on information used from Belgium provides judicially the best applied reference.

Age estimation of Korean children based on dental maturity

The aim of this study was to evaluate the relationship between age and dental maturity and to establish the standard database of dental maturity based on the Demirjians stages, which can be used for the age estimation of Korean children. For this purpose, dental maturity was measured by the Demirjians stages on a randomly selected sample of panoramic radiographs taken from 2706 patients between 1 and 20 years of age and analyzed by multiple linear regression analysis based on the method of least squares. The results showed that, except for the third molars, the development of permanent teeth in Korean children was more advanced in females. The Demirjians stage G of the second molar appeared last in both male and female subjects by age 18, showing 95th percentile at age in the male and female subjects between 16.7-17.4 years and 17.1-17.3 years, respectively. Coefficients of determination (r(2)) of the Demirjians stages relative to age in regression analysis were 0.9721 in male and 0.9740 in female subjects. The standard error was 0.63 years in male and 0.62 years in female subjects. The estimated age according to regression analysis was within +/-1.0 year of the actual age in 92.0% of male and 92.5% of female subjects. Collectively, the data of the present study can be used as a reference for dental maturity and a standard for age estimation of Korean children.

Analysis of residual saliva and minor salivary gland secretions in patients with dry mouth

The importance of oral mucosal wetness in the condition of dry mouth and the role of salivary proteins in proper oral function are acknowledged. A negative correlation between mucosal wetness and the protein concentration of residual saliva has been reported in normosalivators. Here, to examine the suggestion that a reduction in residual salivary volume leads to a concomitant elevation of its protein concentration, the amount of residual saliva and minor salivary gland secretions, and their protein concentrations, were measured in hyposalivators and normosalivator controls. A Periotron 8000 micro-moisture meter was used to measure the thickness of the mucosal film at six selected mucosal surfaces and the minor salivary gland secretion rate at two mucosal surfaces. The unstimulated whole salivary flow rate was measured by the spitting method. The total protein concentration of all salivary samples was measured by bicinchoninic acid assay. The hyposalivators had significantly lower amounts of residual saliva and minor salivary gland secretions than the normosalivators at all selected mucosal sites except the soft palate. In both groups, the site with the thinnest coat of residual saliva was the anterior hard palate and the wettest site was the anterior dorsal mucosa of the tongue. The protein concentration of residual saliva was significantly higher in hyposalivators than normosalivators. In the minor salivary gland secretions there was no significant difference in protein concentration between the normo- and hyposalivators. When the hyposalivators were divided into two subgroups according to their severity of dryness, the reduction of residual salivary volume and the elevation of protein concentration were more apparent in the group with the more severe dry mouth. Collectively, these results indicate that oral mucosal wetness is associated with the flow rate of unstimulated whole saliva. The function of the minor salivary glands was less affected and relatively well preserved in patients with dry mouth. The increased protein concentration of residual saliva in the hyposalivators appeared to be the result of decreased salivary volume.

Development of third molars in Korean juveniles and adolescents

The aim of the present study was to provide reference data of the Korean population which is adequate to compare with other mongoloid populations and can be applied to the age estimation of Korean juveniles and adolescents. A cross-sectional study was performed on a randomly selected sample of 3301 orthopantomographs taken of patients aged from 4 to 26 years, and the developmental stages of the third molars were evaluated based on Demirjians stages. The results showed that the development of third molars in the Korean population was likely to begin at age 7 in both males and females and be completed by age 22 in males and 24 in females at the latest, and the level of development of all four third molars correlated significantly with age in both genders. There were significantly more subjects without third molars in females than in males, however, subjects with all four third molars were significantly more common in males than in females. The Demirjians stages C, F and G could be used as a reference stage to determine dichotomously whether a Korean is more likely to be under or above age 14, 18, or 20, respectively. These results will provide a reference for age estimation of Korean juveniles and adolescents and enable comparison with results from other ethnic populations.

Analysis of residual saliva and minor salivary gland secretions

Residual saliva and minor salivary gland secretions are important for the maintenance of oral mucosal wetness. Salivary proteins and glycoproteins are the major components of the oral mucosal film, which functions as a moisture retainer and a protective barrier. Here, the correlations between the amounts of residual saliva and minor salivary gland secretions and their protein concentrations were investigated in 30 normal healthy individuals. The thickness of the mucosal film was measured at six mucosal surfaces and minor salivary gland secretion rate was measured at two mucosal surfaces. The thickness of residual saliva was determined by placing filter-paper strips against the mucosa at each site for 5 s and then measuring the volume electronically with a Periotron 8000 micro-moisture meter. The unstimulated rate of minor salivary gland secretion was measured for 30 s by the same method. Unstimulated whole salivary flow rate was measured with the spitting method. The total protein concentration of all salivary samples was measured by bicinchoninic acid assay. Before the experiment, the intra-/inter-examiner reliability of the method using the Periotron and the filter-paper strips was investigated. With a range of 0.4256-0.8846, the intraclass correlation coefficient, measured within and between examiners, was indicative of good reliability. The oral mucosal site with the thinnest coat of residual saliva was the anterior hard palate. Mucosal wetness on the hard palate and buccal mucosa showed significant positive correlations with the unstimulated whole salivary flow rate and significant negative correlations with the total protein concentration of residual saliva. Mucosal wetness on the upper and lower labial mucosa also showed significant negative correlations with the total protein concentration of residual saliva. Mucosal wetness on the soft palate was correlated with the minor salivary gland secretion rate (r=0.477, P<0.01). Among the minor salivary glands, the secretion rate of soft palate glands in females showed a significant correlation with the unstimulated whole salivary flow rate (r=0.563, P<0.05) and a significant negative correlation with its total protein concentration (r=-0.525, P<0.05). These data suggested that oral mucosal wetness and minor salivary gland secretions could be influenced by various factors differently according to mucosal sites.

Salivary levels of IL-1β, IL-6, IL-8, and TNF-α in patients with burning mouth syndrome

OBJECTIVE To compare salivary IL-1beta, IL-6, IL-8, and TNF-alpha levels between patients with burning mouth syndrome (BMS) and controls. DESIGN Forty female patients with BMS (mean age: 61.6+/-10.1 years) and 20 female control subjects (mean age: 65.1+/-9.0 years) were included in the study. Unstimulated (UWS) and stimulated whole saliva samples (SWS) were collected and their flow rates were determined. Salivary IL-1beta, IL-6, IL-8, and TNF-alpha levels and total protein concentration were also determined. Salivary transferrin level was determined to investigate the level of blood contamination in saliva samples. Gingival index of the subjects was also examined. Students t-test, Pearsons correlation analysis, and analysis of covariance were used. RESULTS No significant differences were found in the salivary levels of IL-1beta, IL-6, IL-8, and TNF-alpha in BMS patients compared with controls. Salivary flow rates and their total protein concentrations did not differ significantly between the groups. The levels of salivary cytokines and total protein concentration correlated significantly with the level of blood contamination in both UWS and SWS. CONCLUSION There were no differences in the salivary levels of IL-1beta, IL-6, IL-8, and TNF-alpha in BMS patients compared with controls. Cytokine levels in whole saliva were affected mainly by the amount of blood contamination.

Volatile sulfur compounds produced by Helicobacter pylori.

Goals To assess the volatile sulfur compounds produced by three strains of Helicobacter pylori in broth cultures mixed with sulfur-containing amino acids. Background Halitosis has been reported in H. pylori–positive patients, and volatile sulfur compounds such as hydrogen sulfide and methyl mercaptan are known to be responsible for inducing oral malodor. Whether H. pylori produces these volatile sulfur compounds has yet to be established. Study Three strains of H. pylori (ATCC 43504, SS 1, DSM 4867) were cultured with 5 mM cysteine and methionine. After 72 hours of incubation, the headspace air was aspirated and injected directly into a gas chromatograph. The concentrations of hydrogen sulfide and methyl mercaptan were analyzed and compared between experimental and control cultures Results In broth containing 5 mM cysteine, hydrogen sulfide was increased by ATCC 43504 (P<0.01) and SS 1 (P<0.05), while methyl mercaptan was elevated only by SS 1 (P<0.05). In broth containing 5 mM methionine, methyl mercaptan increases were significant for SS 1 (P<0.05) and DSM 4867 (P<0.05). In broth containing 5 mM cysteine and 5 mM methionine, the concentration of hydrogen sulfide was higher than in controls for all three strains (P<0.01); that of methyl mercaptan was higher only for SS 1 (P<0.01). Cysteine addition to cultures containing methionine increased hydrogen sulfide and methyl mercaptan for ATCC 43504 (P<0.05) and SS 1 (P<0.05). Conversely, addition of methionine to cultures containing cysteine increased methyl mercaptan only for DSM 4867 (P<0.01). Conclusions The production of volatile sulfur compounds by H. pylori is not only very complicated but also strain-specific. Nevertheless, H. pylori was shown to produce hydrogen sulfide and methyl mercaptan, which suggests that this microorganism can contribute to the development of halitosis.