The aim of this study is to evaluate the povidone-iodine for the suppression of oral cariogenic bacteria and compare its effects to that of fluoride in children. We carried out a randomized controlled trial to compare the effects of povidone-iodine to those for sodium fluoride. Pre-school children (n = 210) with more than 105 cfu/ml mutans streptococci in their stimulated saliva were randomly sampled and randomly allocated into three groups. We planned the preventive program by 3DS (Dental Drag Delivery System). The groups that provided preventive programs were the povidone-iodine group (n = 70) and the sodium fluoride group (n = 70). A control group (n = 70) received no intervention. Povidone-iodine or sodium fluoride was applied to the tooth surface using custom made trays. Subsequent home care was obligatory for one month. After one month, the salivary levels of mutans streptococci were low level when compared to the based data. However the difference in salivary levels of mutans streptococci among groups was not statistically significant when comparing the povidone-iodine group with the sodium fluoride group (P = 0.625). After 2.5 years follow up, differences in incidence of new dental caries among the three groups were not statistically significant (P = 0.583). Clinical application of anti-microbial drugs may be effective, but only a single intervention is not sufficient to reduce the incidence of new dental caries.
The objective of this study was to evaluate the perceptions of some Nigerian children regarding consenting to their dental treatment. The sample consisted of 100 child patients with an age range of 8-13 years. Children requiring emergency treatment were excluded from the study. A semi-structured questionnaire was administered and the dentists carried out interviews following dental treatment. The outcome of the study revealed that 64% of the respondents were of the opinion that children generally should be involved in deciding about their dental treatment. Results showed that 37% of these children were actually involved in the decision about the dental treatment they had received whereas 66% believed that they should have been part of the process. Responses from the children revealed that 49% wanted the dentist to talk to them about their dental treatment while 41% felt it was the responsibility of both their parents and the dentist. The results of this study have suggested that children want to be more involved in consenting to their dental treatment.
We sent questionnaires to all the members (4,298 people) about the specialist pediatric dentistry system in Japan (Hereafter, termed specialists). The survey (1,129 dentists answered the questionnaire) revealed the following: 1. About 29% of the members who have qualifications for pediatric dentists, authorized by Japanese Society of Pediatric Dentistry (JSPD), hoped for a specialist qualification immediately. 2. Eighty point six percent of the members who do not have qualifications authorizing them as pediatric dentists answered that they wanted to take an examination to become a specialist as soon as they were qualified to take it. 3. Many members hoped that the examination to become a specialist would be strictly carried out. 4. Twenty-two point eight percent members thought that the qualifications for pediatric dentists authorized by Japanese Society of Pediatric Dentistry should be abolished after putting the specialist system into effect. 5. Fourteen percent of those that have the qualification of pediatric dentists, authorized by Japanese Society of Pediatric Dentistry, did not want to acquire the specialist title but they wanted to renew their current qualifications. 6. As dentists got older, the ratio of children patients (under 18 years old) tended to decrease. 7. However, about one-quarter, 112 members (about 10% of all) of dentists who are 50-69 years old (347 members) it occupied 34.7% of all treated exceeded 90% children patients.
Periodontitis is a widespread and serious dental disease that results from multifactorial and lifestyle-related causes. Patients with Down syndrome have a high risk of periodontal disease from an early age, but little is known about the genetic factors that may cause or exacerbate it. With this regard, we isolated DNAs from lingual mucosal cells and examined the frequency of specific single nucleotide polymorphisms (SNPs) by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The SNPs on which we focused were of the pro-inflammatory cytokine genes Interleukin (IL)-1A(-889) and IL-1B(+3953), and of the Toll-like receptor genes (TLR)2(Arg677Trp) and TLR4(Asp299Gly). The subjects of the study, all of Japanese extraction, were: (i) 18 individuals with Down syndrome and periodontitis; (ii) 10 individuals with Down syndrome and no periodontitis; (iii) 20 control individuals without Down syndrome but with periodontitis; and (iv) 10 control individuals without periodontitis. The patterns of occurrence of SNPs of the IL-1A, IL-1B, TLR2 and TLR4 were similar in all groups.
The purpose of the present study was to examine age-related change of the pulpal blood flow (PBF) in human primary teeth. PBF of 21 healthy upper primary central incisors in 12 children (age: 3 years 11 months-7 years 3 months) was measured by laser Doppler flowmetry (LDF). Recordings were made with and without opaque black rubber dam application. On 10 of the examined teeth, repeated measurements were made on different occasions: twice on 4 teeth (3 subjects) and 3 times on 6 teeth (3 subjects). The results obtained were as follows: 1) PBF with dam application was significantly decreased with increasing age of the subjects (P < 0.05, Spearman ranks order correlation, n = 21). 2) In the repeated measurements, PBF showed a tendency of decrease with age. These results indicate that PBF in human primary incisors is reduced with age.
In general, pulpotomy is evaluated by pathological examination of sacrificed animals at each observing stage. Not only lots of small animals have to devote itself to experimentation, but also the result of research is lacking about the serial observation of an individual experimental animal. The aim of this study was to compare the relative effectiveness of the calcium hydroxide, formocresol and CO2 laser using the R_mCT®. Twenty male Wistar rats, 8 weeks of age, were used and imaged in present study. They were serially observed using the R_mCT® on days 0, 3, 10, 30, 50 after pulpotomy, followed pathohistological examination. The R_mCT® images revealed that the pulp capping agents were partly absorbed and a hard tissue-like was observed immediately beneath it, especially in the CO2 laser group. Pathohistological examination showed a hard tissue-like appearance and inflammatory cell infiltration. The R_mCT® images agreed with pathohistological finding on the days 50 after pulpotomy. Our research suggested that the R_mCT® has made it possible to scan serial imaging of small animals such as experimental rats under anesthesia. Since its higher resolution enables clear observation of the entire hand of the rat, it is possible not only to compare the effectiveness of each pulpotomy method, but also to serially observe a single experimental animal during the process post-pulpotomy healing, growth, and aging. This study answered well for the animal protective law that to use the least of animal to got the best result.
Macrophages are essential for controlling the majority of infections, and are mediators of natural immunity. Namely, macrophages are the main cells that secrete anti-inflammatory cytokines, such as IL-10. IL-10 is an important suppressive cytokine, produced by many kinds of immune cells, which plays a key role in the anti-inflammatory immune responses. Adenosine mediates many of its effects through one or more of four receptors, the adenosine A1, A2A, A2B, and A3 receptors, and it has been shown that A2A adenosine receptor (A2AR) is a critical part of the physiological negative feedback mechanism for limitation and termination of tissue-specific and systemic inflammatory responses. Mac-1 is an adhesion molecule required for apoptosis induced by other cell surface receptors, and is expressed on the surface of macrophages. Mac-1 expression is also necessary for the termination of an inflammatory reaction. To demonstrate how adenosine has its affects on macrophages to control inflammation, we evaluated the effects of adenosine in the RAW264 and THP-1 macrophage cell lines. Adenosine did not affect the proliferation in RAW264 cells regardless of the concentration. On the other hand, adenosine increased IL-10 production in RAW264 cells. Moreover, adenosine markedly increased the expression of CD11b, which is a Mac-1 alpha integrin. These results indicate that adenosine may affect the anti-inflammatory reactions in macrophages by enhancing the production of IL-10, and influence apoptosis by expression of CD11b.
This study examined the effect of tube feeding on hippocampal Fos induction and spatial performance in a water maze task in senescence-accelerated mice (SAMP1). Tube feeding accelerated the age-related decline in spatial memory and decreased Fos induction in the hippocampal CA1 region in aged SAMP1 mice. The results suggest that tube feeding in aged SAMP1 mice reduces input activity in the hippocampus, thereby leading to senile memory deficits.
Mutans streptococci considered causative agents of dental caries are indigenous to the oral cavity. Modified mitis-salivarius-bacitracin (MSB) agar medium was supplied by BML. This media has characters to grow mutans streptococci very well and to inhibit of non-mutans streptococci. However, little is known about studies using this medium. In this study, we assessed the utility of modified MSB medium and discuss the relation between mutans streptococci and dental caries in primary dentition period. Modified MSB medium was found to be a suitable medium to isolate and quantify mutans streptococci since it could permit selective growth of mutans streptococci. Moreover, this medium inhibited to non-mutans streptococci (S.anginosus and S.intermedius), completely. The detection rate of Streptococcus mutans and Streptococcus sobrinus increased in proportion to the severity of dental caries in the nursery children. From these results, modified MSB agar medium is useful in the judgment to detect the mutans streptococci.
Scutellaria baicalensis Georgi has been used for thousands of years in traditional Chinese medicine practice for several purposes. It possesses several biological activities such as anti-oxidative, anti-inflammatory, antibacterial and antiviral activities. Although the antibacterial activity of Scutellaria baicalensis Georgi has already been demonstrated, little is known about its antibacterial activity against oral pathogens in vitro. Therefore, the aim of this study is to evaluate the antibacterial activity by six different kinds of Scutellaria baicalensis Georgi extracts in vitro. The three kinds of bacterial strains were used as follows: Streptococcus mutans ATCC 25175, Streptococcus sobrinus ATCC 33478 and Streptococcus salivarius ATCC 7073. The antibacterial activity was determined by the agar diffusion method, and the zones of growth inhibition were measured. The MIC’s and MBC’s were determined by the broth dilution and agar dilution methods. The bactericidal activity was determined by time-kill assay. In all the Scutellaria baicalensis Georgi solvent extracts, except for water and ethyl acetate, a significant inhibitory activity was observed. The acetone and 80% ethanol, and the ethanolic extracts showed higher activity than the methanol extracts and produced inhibition zones ranging from 7.11±0.18 to 14.79±1.02 mm in diameter at a concentration of 750 μg/disk. The MIC value of the Scutellaria baicalensis Georgi extracts ranged from 125 to 1,000 μg/ml. The MBC values for different strains and extracts ranged from 250 to 2,000 μg/ml. Thus, Scutellaria baicalensis Georgi would be useful for the suppression of oral pathogens, and has the potential for use in the prevention of dental caries.
The present study was carried out to investigate the oral status of 234 Japanese infants, who had registered at the Pediatric Dentistry Clinic of Niigata University Medical and Dental Hospital over a period of 26 years, from 1979 to 2005. The 234 infants consisted of 125 males and 109 females and the youngest patient was 2 days old. We divided them into 11 groups based on the diagnosis. The groups consisted of 46 oral mucosal lesions (8 patients were counted again with natal teeth), 45 cleft lip and/or palate infants, 28 with normal oral condition, 26 high maxillary frena, 21 natal or neonatal teeth, 21 traumatic injuries, 15 teeth anomalies, 14 ankyloglossia, 11 eruption problems, 8 occlusal problems, and 7 with other conditions. Among the 234 cases, some very rare conditions were noted, including a prematurely exfoliated supernumerary deciduous tooth in a 2-month-old infant, 3 cases of palatal polyps, and 2 cases of epulides. It was shown that infants exhibit many kinds of oral conditions that require professional attention from pediatric dentists.
Although there are numerous reports on detection of bacteria causing periodontal diseases within the oral cavity, most of these treat the oral cavity as a single entity. The objective of this study was to determine whether there was site-specificity in the detection of certain bacteria in supragingival plaque from different regions of the oral cavity. The subjects were six adults with no recognized oral problems. We examined eight regions; the labial and lingual surfaces of the upper and lower anterior teeth and the upper and lower first molars. The target bacteria included five species of bacteria that cause periodontal diseases. After professional medical tooth cleaning (PMTC), the volunteers performed no oral prophylaxis for three days. Then we collected about 1 μl of plaque from each of the regions by excavators. We searched for the five species of bacteria by immunoslot-blot assay and compared the results from the respective regions. We discovered that the detection rate was very small for all five bacterial species on the lingual surface of the lower anterior teeth, which is known to have good salivary clearance. On the labial surface of the upper anterior teeth, which is commonly believed to have poor salivary clearance, the detection rate was higher but there was no specificity with respect to detection rate. The regions with the highest detection rates were the buccal surface of the upper and lower molars. On the lower molars, larger populations of Porphyromonas gingivalis and Prevotella nigrescens were detected. On the upper molars, Prevotella intermedia and Prevotella melaninogenica were detected. These results suggest that there is regional specificity in the presence of periodontopathic bacteria in the mouth.
OBJECTIVES: The concentration of the substances eluted from the gum into saliva before and after swallowing has not almost carried out. The purpose of this study was to measure the volume of saliva before (VMAX) and after (RESID) swallowing in the mouth and was also to measure the concentration of the component (sugar) eluted from the gum chewing. METHODS: The RESID was measured by a dilution method (Lagerlof and Dawes, 1984). It was computed by measuring the potassium concentration in saliva and in the expectorated after a five-second rinse with 10 ml of water immediately following a swallow. The volume swallowed was calculated as salivary flow rate divided by the swallowing frequency, and the VMAX was estimated as the sum of RESID and the volume of saliva swallowed. Swallows were registered by placing over the larynx an electrode which was connected to an EMG. The volume of sugar contained in the gum was 74.8% as a total weight of the gum. Subjects were seven males and 13 females who were all in good health for measuring the RESID and VMAX. For each of the six participants of them, the concentration of sugar in saliva expectorated was measured by frame photometer. RESULTS: VMAX, swallowing frequency and the volume of fluid swallowed increased as comparing with the values when the salivary flow rate was unstimulated. The mean volume of sugar in expectorated saliva as a percentage of the initial weight of sugar contained during gum chewing at the first swallowing was 16.5±5.38% and at the 10th swallowing was 0.76±0.06%. These were 3.6 times and 1.8 times of those of unstimulated saliva, respectively.
Four patients with hypophosphatasia, including twin brothers and younger and older sisters, were analyzed longitudinally. Ten periodontitis-related bacterial species in dental plaque were detected using a Polymerase chain reaction (PCR) method with species-specific sets of primers. Further, clinical parameters related to periodontal conditions were recorded at each visit. One of the twins, who had experienced early exfoliation of the primary teeth, had a greater number of bacterial species than his brother, who had no alveolar bone loss. Both of the sisters experienced early exfoliation of their primary teeth, and the average numbers of tested bacterial species were higher in other subjects of the same age. Our results indicate that impaired cementum tissue caused by hypophosphatasia may produce favorable sites for colonization of periodontitis-related bacteria.
We present a case of radicular-gingival groove identified in the mandibular left lateral incisor. A female visited our clinic at the age of 11Y5M complaining of repeated gingival inflammation. An intraoral examination found severe gingival swelling in the affected region, while clinical examinations revealed a groove from the cingulum to the apex of the mandibular left lateral incisor. A gingivectomy and professional brushing instruction were performed, with follow-up examinations given periodically. After a long interval, the patient returned at the age of 18Y4M and reported that gingival inflammation had repeatedly occurred. Subgingival dental plaque samples were collected from the affected area as well as areas around 3 normal teeth with a periodontal healthy condition, along with a saliva sample. Using bacterial DNA extracted from each sample, detection of 10 putative periodontopathic bacterial species was done by PCR, which identified Tannerella forsythensis, Campylobacter rectus, Eikenella corrodens, Actinobacillus actinomycetemcomitans, and Capnocytophaga sputigena in the sample from the affected region. Further, broad-range PCR targeting 16S rRNA with direct sequencing of the samples showed a variety of bacterial species, including Neisseria, Corynebacterium, and Fusobacterium. Streptococcus species occurred at a high rate in the plaque samples from the control teeth, whereas there were none in the affected region. Our findings indicate that the bacterial profile in the area of a radicular-gingival groove may be different from other periodontal healthy sites, which might be related to the occurrence of repeated inflammation in the groove area.
We report a rare case of eruption disturbance of the bilateral second molars caused by supernumerary teeth in a 7-year-old Japanese boy. The supernumerary teeth were detected by radiographic examination. Computed tomography (CT) was used to examine the positional relationship of the supernumerary teeth and neighboring second molars. CT images showed conical-shaped supernumerary teeth on the upper buccal side of the unerupted mandibular second molars. The cusps of the supernumerary teeth pointed toward the lingual side. Because the two supernumerary teeth threatened to disturb the eruption of the second molars, they were surgically removed at 2 years and 4 months after diagnosis. After removal of the supernumerary teeth, the mandibular second molars erupted at a normal age and aligned normally within the dentition. To the best of our knowledge, this is only one case report of eruption guidance for eruption disturbances of the bilateral second molars caused by supernumerary teeth.