The effect of dentifrice including dental type silica, tocopherol acetate, sodium fluoride and sodium pyrophosphate on mineral density in enamel / 대한구강보건학회지

Objectives@#In this study, we aimed to investigate the preventive and protective effects of new dentifrice containing dental type silica, tocopheryl acetate, fluorides, and sodium pyrophosphate on the mineral density of teeth and demineralization of tooth surfaces. @*Methods@#A total of 119 bovine teeth pre-treated with the new dentifrice at three different concentrations for the experiment were randomly allocated into two control (DW and PW) and one experimental (EC) groups. The enamel surface of all bovine teeth were demineralized using an artificial demineralization solution. The dentifrice was diluted with distilled water (DW) at 1:1, 1:2, and 1:3 ratios. The samples were treated with the demineralization solution for 4 h after treatment with the supernatants of each diluted dentifrice for 30 min, and this procedure was repeated 3 times over a period of 24 h. The samples were examined using micro-CT to determine the amount of reduced bone mineral density (BMD) comparing the control and experimental dentifrices. The surface changes of the samples were also examined using the scanning electron microscope (SEM). @*Results@#The average BMD of the bovine enamel surface between the treated and non-treated area with the dimineralization solution was significantly different in the control, DW, PW 1:1, PW 1:2, and PW 1:3 groups. However, there was no significant difference observed in the experimental groups, including EC 1:1, EC 1:2, and EC 1:3. The average BMD of the dimineralized surfaces based on the results of the 7 groups was significantly higher in every EC group when compared to the DW and three PW groups. @*Conclusions@#The new dentifrice containing dental type silica, tocopheryl acetate, fluorides, and sodium pyrophosphate is effective in inhibiting the decrease in BMD and demineralization of enamel surface, which was observed when the new dentifrice and demineralization solution was repeatedly applied to the samples for 24 h.

The effect of dentifrice including dental type silica, tocopherol acetate, sodium fluoride and sodium pyrophosphate on mineral density in enamel / 대한구강보건학회지

Objectives@#In this study, we aimed to investigate the preventive and protective effects of new dentifrice containing dental type silica, tocopheryl acetate, fluorides, and sodium pyrophosphate on the mineral density of teeth and demineralization of tooth surfaces. @*Methods@#A total of 119 bovine teeth pre-treated with the new dentifrice at three different concentrations for the experiment were randomly allocated into two control (DW and PW) and one experimental (EC) groups. The enamel surface of all bovine teeth were demineralized using an artificial demineralization solution. The dentifrice was diluted with distilled water (DW) at 1:1, 1:2, and 1:3 ratios. The samples were treated with the demineralization solution for 4 h after treatment with the supernatants of each diluted dentifrice for 30 min, and this procedure was repeated 3 times over a period of 24 h. The samples were examined using micro-CT to determine the amount of reduced bone mineral density (BMD) comparing the control and experimental dentifrices. The surface changes of the samples were also examined using the scanning electron microscope (SEM). @*Results@#The average BMD of the bovine enamel surface between the treated and non-treated area with the dimineralization solution was significantly different in the control, DW, PW 1:1, PW 1:2, and PW 1:3 groups. However, there was no significant difference observed in the experimental groups, including EC 1:1, EC 1:2, and EC 1:3. The average BMD of the dimineralized surfaces based on the results of the 7 groups was significantly higher in every EC group when compared to the DW and three PW groups. @*Conclusions@#The new dentifrice containing dental type silica, tocopheryl acetate, fluorides, and sodium pyrophosphate is effective in inhibiting the decrease in BMD and demineralization of enamel surface, which was observed when the new dentifrice and demineralization solution was repeatedly applied to the samples for 24 h.

Association between unmet needs for dental treatment and the DMFT index among Korean adults / 대한구강보건학회지

OBJECTIVES: Unmet needs for dental treatment are one of the potential contributing factors to poor oral health because oral health problems worsen if left untreated. This study aimed to demonstrate the prevalence of and the causes for unmet dental needs, and to evaluate the association between unmet needs for dental treatment and oral health status. METHODS: Data on 3,883 subjects aged ≥18 years from the Korean National Oral Health Survey 2006 were analyzed. Information regarding unmet needs for dental treatment was obtained using standardized questionnaires. Eight trained dentists examined decayed, missing, or filled teeth (DMFT). Multiple regression models were built to assess the association between unmet needs for dental treatment and the DMFT scores. RESULTS: The prevalence of perceived unmet needs for dental treatment was 34.7% among the adult Korean population. Economic constraints were the main cause (38.6%) for unmet dental needs. The average DMFT scores were higher in the subjects with unmet needs for dental treatment than in those without. In individuals with unmet needs for dental treatment within the past 1 year, the number of decayed teeth after adjusting for confounders was likely to be greater by 0.58 and that of missing teeth by 0.27 compared to that in their counterparts with no unmet dental needs in the past 1 year. CONCLUSIONS: Perceived unmet needs for dental treatment were significantly associated with poor oral health status among the adult Korean population. Further studies are needed to clarify the direct and indirect effects of unmet needs for dental treatment on an individual's oral health status by investigating critical variables of the causal pathways among perceived dental needs, dental care utilization, and oral health status.

Magnetic Resonance Imaging of Breast Cancer Patients with BRCA Mutation

PURPOSE: To evaluate the MRI findings of breast cancer with BRCA mutation. MATERIALS AND METHODS: We collected information of the breast cancer patients who underwent the test for BRCA gene mutation as well as preoperative breast MRI from January 2007 to December 2010. A total of 185 patients were enrolled; 33 of these patients had BRCA mutations and 152 patients did not. Among them, a total of 231 breast cancers were detected. Images of the 47 breast cancers with BRCA mutation and of the 184 breast cancers without mutations were evaluated to compare the morphologic and enhancement features on MRI. RESULTS: With MR imaging, there were no significant difference in morphologic characteristic between two groups. However, enhancement pattern in the group with BRCA mutation were more likely to have persistent enhancement (p < 0.233), and LN metastasis was more common in breast cancers without BRCA mutation. Breast cancers with BRCA 2 mutation tend to show more persistent enhancement pattern than BRCA 1 mutation. CONCLUSION: In breast cancer patients with BRCA mutation, MRI didn't show significant difference in morphologic characteristics, however breast cancers with BRCA gene mutation carriers tend to have benign morphologic features on MRI, such as Type 1 kinetic curve enhancement.

Comparison between CT Colonography and Double-Contrast Barium Enema for Colonic Evaluation in Patients with Renal Insufficiency

OBJECTIVE: To compare the CT colonography (CTC) and double-contrast barium enema (DCBE) for colonic evaluation in patients with renal insufficiency. MATERIALS AND METHODS: Two sequential groups of consecutive patients with renal insufficiency who had a similar risk for colorectal cancer, were examined by DCBE (n = 182; mean +/- SD in age, 51 +/- 6.4 years) and CTC (n = 176; 50 +/- 6.7 years), respectively. CTC was performed after colon cleansing with 250-mL magnesium citrate (n = 87) or 4-L polyethylene glycol (n = 89) and fecal tagging. DCBE was performed after preparation with 250-mL magnesium citrate. Patients with colonic polyps/masses of > or = 6 mm were subsequently recommended to undergo a colonoscopy. Diagnostic yield and positive predictive value (PPV) for colonic polyps/masses, examination quality, and examination-related serum electrolyte change were retrospectively compared between the two groups. RESULTS: Both the CTC and DCBE were positive for colonic polyps/masses in 28 (16%) of 176 and 11 (6%) of 182 patients, respectively (p = 0.004). Among patients with positive findings, 17 CTC and six DCBE patients subsequently underwent a colonoscopy and yielded a PPV of 88% (15 of 17 patients) and 50% (3 of 6 patients), respectively (p = 0.089). Thirteen patients with adenomatous lesions were detected in the CTC group (adenocarcinoma [n = 1], advanced adenoma [n = 6], and non-advanced adenoma [n = 6]), as compared with two patients (each with adenocarcinoma and advanced adenoma) in the DCBE group (p = 0.003). Six (3%) of 176 CTC and 16 (9%) of 182 DCBE examinations deemed to be inadequate (p = 0.046). Electrolyte changes were similar in the two groups. CONCLUSION: In patients with renal insufficiency, CTC has a higher diagnostic yield and a marginally higher PPV for detecting colorectal neoplasia, despite a similar diagnostic yield for adenocarcinoma, and a lower rate of inadequate examinations as compared with DCBE.

Structural equation modeling for association between patient satisfaction and quality of life after implant surgery / 대한치과보철학회지

PURPOSE: This study was designed to measure patient satisfaction and oral health-related quality of life and to assess an association between patients' satisfaction and oral health-related quality of life after implant surgery by using structural equation modeling. MATERIALS AND METHODS: A total of 257 participants who visited 6 dental clinics located in Daegu city for the purpose of implant treatment participated in this study. Six months after completion of implant surgery, the patients' satisfaction and oral health-related quality of life were surveyed. The effect of factors associated with patients' satisfaction such as functions and aesthetics, maintenance and cost on oral health-related quality of life after implant surgery was analyzed using AMOS 4.0. RESULTS: Oral health-related quality of life was improved in all dimensions of OHIP-14 after implant surgery. Functions and aesthetics as well as maintenance had a significant effect on oral health-related quality of life (P<.05), while cost was not a critical factor influencing oral health-related quality of life. CONCLUSION: High satisfaction with functional aspects and maintenance aspects significantly affected good quality of life. The result of this study supported the fact that education and management for patients after implant therapy were positively related to good quality of life based on a theoretical model.

Association between Amalgam Tooth Fillings and Blood Mercury Levels in Children

The notion that dental amalgam is a potential source of mercury exposure remains a controversial issue. However, there are few epidemiological analyses that have addressed whether this occurs in children. We aimed in our current study to identify the relationship between dental amalgam filling surfaces and the blood mercury levels in a cohort of 711 South Korean children aged between 8-9 years. Oral examinations were conducted to detect the number of amalgam filling surfaces on the teeth of these individuals. Blood samples were also taken from these children to assess the levels of mercury accumulation in the body. The amalgam filling surfaces were classified into four groups based on their number: 0 (n = 368), 1-5 (n = 219), 6-10 (n = 89), and 11+ (n = 35). The blood mercury levels in the children with more than 10 amalgam surfaces was 0.47 microg/L higher on average than those with no amalgam surfaces after adjusting for the frequency of fish or seafood consumption, age, and gender (P < 0.05). We found from our data that a higher number of dental amalgam fillings correlated with a higher blood mercury level in Korean children. Further studies are needed to investigate whether these elevated mercury levels exert neurotoxic or nephrotoxic effects.

Use of Self-Expanding Stents for the Treatment of Vertebral Artery Ostial Stenosis: a Single Center Experience

OBJECTIVE: To evaluate our early experience using self-expanding stents to treat atherosclerotic vertebral artery ostial stenosis (VAOS), with respect to technical feasibility and clinical and imaging follow-up results. MATERIALS AND METHODS: A total of 20 lesions in 20 patients underwent stenting of the VAOS using a self-expanding stent (Precise RX; Cordis Neurovascular, Miami Lakes, FL). Two patients were asymptomatic. We analyzed the technical success rate, causes of technical failure, occurrence of any vascular or neurological event, and the occurrence of any neurological abnormality or in-stent restenosis (ISR) seen on follow-up. The imaging follow-up was performed with Doppler ultrasound (DUS) as a primary screening modality. RESULTS: One instance of technical failure was caused by failure of the guidewire passage. The stent diameter was 5 mm, and post-stenting balloon dilatations were necessary in all cases. Stent misplacement requiring placement of an additional stent occurred in four cases. Following a 14.8 month average clinical follow-up time, two patients showed anterior circulation ischemia, which was not attributed to the VAOS we treated. Following a 13.7 month average DUS follow-up, five patients showed a mild degree of diffuse or focal intimal thickening in the stent lumen; however, none of the stenosis showed luminal loss of more than 50% and no stent fracture was noted. CONCLUSION: The use of self-expanding stents for treating VAOS was technically feasible and helped to improve artery patency during our limited follow-up interval.

Severe Atherosclerotic Cerebral Steno-occlusion in Koreans: Factors Related to Intracranial versus Extracranial Involvement / 신경중재치료의학

PURPOSE: To evaluate the factors related to severe intracranical atherosclerotic stenosis (intracranial vs. extracranial) as diagnosed by conventional angiography in Korean patients. MATERIALS AND METHODS: We retrospectively analyzed the angiographic results and clinical data of 127 consecutive patients with an angiographically confirmed stenosis greater than 70%. Nine factors, i.e. age, gender, hypertension, diabetes mellitus, hyperlipidemia, smoking and alcohol habit, previous stroke and ischemic heart disease were included as presumed explanatory variables to discriminate different types of atherosclerotic stenosis (extracranial versus intracranial stenosis). Multiple logistic regression analysis was used to estimate independent effects of the predictive variables on cerebral occlusive disease. RESULTS: Among 127 patients, 62 patients had intracranial stenosis and 65 patients had extracranial stenosis. Compared to extracranial stenosis, mean age was lower (p < 0.001), female-to-male ratio was higher (p = 0.001) and the number of patients with diabetes mellitus was less (p = 0.019) in group of severe intracranial stenosis significantly. There were no differences in hypertension, smoke and alcohol, hyperlipidemia, ischemic heart disease and previous stroke between two groups. CONCLUSION: In Korean patients, severe atherosclerotic intracranial stenosis has younger, female and diabetes-free preference than severe atherosclerotic extracranial stenosis.

Immunohistochemical Localization of Glycine Receptor (alpha1+alpha2) in the Auditory Brain Stem of Circling Mouse / 대한해부학회지

Hearing loss in adults can stem from damage to the cochlea and the cochlear nerves inflicted by intense noise, mechanical trauma, or disease. Hearing loss is associated with degenerative changes in central auditory pathways, and hearing deficits are often accompanied by changes in the synaptic organization of the central auditory pathways. In addition to structural rearrangements, hearing loss may induce changes in the strength of synaptic transmissions. These effects may alter both transient and persistent regulation of transmitter release from glutamatergic, glycinergic, and GABAergic pathways in the auditory brain stem. The converging excitatory and inhibitory inputs are exquisitely organized topographically and are aligned perfectly with each other. The LSO and MNTB in the mammalian auditory brain stem provide and receive many glycinergic inputs. Thus, this auditory system is a useful model to study inhibitory synaptic development. However, little is known about the inhibitory synapses in the central nervous system. First, we used immunohistochemistry to compare the glycine receptor (GlyR) distribution in the LSO and MNTB, which project glycinergic inhibitory input into the auditory brainstem, in circling mice (P16), which have a spontaneous mutation in the inner ear, with wild-type mice. The relative immunoreactive density of the LSO was 86.4+/-7.2 in wild-type, 76.7+/-10.7 in heterozygous, and 61.1+/-4.1 in homozygous mice. The relative immunoreactive density of the MNTB was 97.6+/-8.7 in wild-type, 91.7+/-8.9 in heterozygous, and 74.9+/-7.8 in homozygous mice. These results reveal a decreased GlyR immunoreactivity in both the LSO and MNTB, which may be attributable to a postsynaptic decrease in GlyR number. Our model uses congenitally deaf mice, in which both spontaneous and evoked auditory nerve activity are disrupted because of dysfunctional hair cell-spiral ganglion cell transmission. This provides a naturally occurring model that may provide valuable insights into the central aspects of human congenital deafness in addition to the central consequences of a lack of auditory nerve activity. Our results are likely to be relevant to our understanding of the central changes underlying human hereditary deafness.

The Significance of Stretch Reflex Threshold Speed in Quantitative Assessment of Spasticity

OBJECTIVE: This study was designed to evaluate the usefulness of stretch reflex threshold speed (SRTS) in biomechanical assesment of spasticity of hemiplegic patients. METHOD: Thirty-eight hemiplegic patients and twenty-seven control subjects were studied. The spasticity of ankle plantar flexor muscles were assessed both clinically and biomechanically. Modified Ashworth scale (MAS) and Brunnstrom stage were used in clinical assessment. For biomechanical assessment, ankle plantar flexor muscles were stretched isokinetically while EMG signals were recorded simultaneously. SRTS was defined as a minimum angular velocity in which EMG signals evoked by stretch reflex were recorded. RESULTS: SRTSs of ankle plantar flexors were 128.1 47.1o/sec in control group, 163.7 79.7o/sec in intact legs, and 83.4 69.1o/sec in involved legs of hemiplegic group. STRS was significantly lower in involved legs of hemiplegic group than in intact legs of hemiplegic group and control group. Significant reverse correlation was observed between SRTS and MAS. There was significant difference in SRTS between MAS 0 group and other groups. The patients with Brunnstrom stage 3 and 4 groups showed decreased SRTS compared to the patients with other groups. CONCLUSION: SRTS is thought to reflect increased excitability of stretch reflex and seems to be one of useful parameters in quantitative assessment of spasticity.

Quantitative Evaluation of Dysphagia Using Scintigraphy

OBJECTIVE: To investigate the clinical usefulness of scintigraphy for the evaluation of dysphagia in patients with brain lesion and to clarify the most useful quantitative parameter for detection of aspiration using scintigraphy. METHOD: For 42 patients with dysphagia, swallowing evaluations were done by videofluoroscopy and scintigraphy. According to videofluoroscopic findings these patients were grouped into three; aspiration, laryngeal penetration and no penetration group. Quantitative parameters from scintigraphy were measured and compared among three patients groups and normal control; these parameters were oral discharge time (ODT), pharyngeal transit time (PTT), oral residue (OR), pharyngeal residue (PR), pharyngeal swallowing efficiency (PSE) and oro-pharyngeal swallowing efficiency (OPSE). Sensitivity and specificity of these parameters detecting aspiration were also evaluated according to the videofluoroscopic findings. RESULTS: In aspiration group ODT, PTT, PSE and OPSE were 1.18+/-1.14 sec, 1.80+/-1.49 sec, 86.05+/-61.42%/sec and 38.21+/- 28.65%/sec respectively, all of which were significantly different from the other groups, but OR and PR were not different statistically. According to the ROC (Relative Operating Characteristic) table, sensitivity and specificity of OPSE were 72.7 and 80.7% respectively, which were the highest among the parameters. CONCLUSION: Scintigraphy was useful to quantitative dysphagia in patients with brain lesion. Sensitivity and specificity of swallowing efficiency was higher than time and residue parameters. OPSE was considered to be the most useful quantitative parameter for detecting aspiration.