OBJECTIVETo study the dental caries status of the 65-74 years old people in northeast of China, analyze the distribution of caries in the group of people, and provide scientific basis for establishing the oral health care policies.

METHODSThe representative samples were selected by multi-stage, stratified and random sampling from the three province of northeast of China. Dental caries of 2 364 people aged 65-74 were recorded according to WHO criteria. SPSS 12.0 software was used to analyze the data.

RESULTS1) Among 2,364 elderly people in northeast of China, the prevalence of dental caries was 67.5% and DFT was 2.68, the composition of filling was 10.82%. 2) The prevalence of coronal caries was 66.4% and DFT was 2.55. The composition of filling was 11.37%. 3) The prevalence of root surface caries was 48.4% and DFT was 1.64. The composition of filling was only 1.8%.

CONCLUSIONThe prevalence of dental caries among elderly people in northeast of China is still very high, and the filling rate is low. The community based oral health promotion should be strengthened and preventive-oriented oral health care systems are needed in northeast of China.

Aged ; China ; Dental Caries ; Humans ; Prevalence ; Risk Factors ; Root Caries

OBJECTIVETo investigate the genotypic diversity of Actinomyces naeslundii in aged people and the relationship between the genotypes of Actinomyces naeslundii and root caries.

METHODSAccording to the inclusion criteria, 20 aged people with root caries and 20 without root caries were chosen into two groups for this study. Two sites were chosen in subjects with root caries: One site was the exposed sound root surface, and the other site was the root caries. In subjects without root caries the sampling site of root surface was exposed. Bacteria were cultured and then identified. Repetitive extragenic palindromic sequence-based polymerase chain reaction (REP-PCR) was used to analyze the genotypic diversity of the Actinomyces naeslundii clinic isolates.

RESULTS299 strains were isolated from the groups, 156 strains were chosen to analyze, belonged to 61 different genotypes. At the site of sound root surface in the subjects with root caries, there were 57 strains with 25 different patterns. At the site of root caries and of sound root surface in subjects without caries, there were 34 strains with 25 different patterns and 65 strains with 26 different patterns respectively. There was the genotypic diversity within Actinomyces naeslundii. There was significant difference in the genotypes in every individual site.

CONCLUSIONMany different genotypes of Actinomyces naeslundii concerned with occurrence of root caries.

Actinomyces ; Aged, 80 and over ; Dental Caries ; Genotype ; Humans ; Polymerase Chain Reaction ; Root Caries ; Tooth Root

OBJECTIVETo survey the tooth decay of the first molars among the people in area of northeast China in order to provide the foundation for prevention and treatment strategies of caries.

METHODSAccording to the third national oral health investigation of epidemiology, the dental caries of first permanent molars were examined among 9394 people aged 5, 12, 35-44 and 65-74 in northeast China. The data were analyzed by SPSS 13.0 statistical software. Dental caries prevalence rate and DMFT (dmft) of first permanent molar were calculated.

RESULTSThe prevalence of crown and root dental caries in northeast China were 26.86% and 3.81% respectively, mean DMFT (dmft) of crown and root dental caries were 0.41 and 0.04 respectively. There were significant differences of dental caries among provinces in northeast China. Mandibular first molar suffered from dental caries easily. The prevalence of caries of female was higher than that of male (P<0.01), but there was not significant difference of prevalence of root caries between two sexes (P>0.05). Except Jilin province, there were significant differences of prevalence of crown caries between city and rural area in Liaoning and Heilongjiang provinces (P<0.01). It was no significant difference of prevalence and mean DMFT (dmft) of root caries between city and rural area in each province (P>0.05).

CONCLUSIONThe prevalence of dental caries of the first molar among the people in northeast China is high. The dental caries prevention and cure of first permanent molar should be emphasized in oral health field.

China ; Dental Caries ; Female ; Humans ; Male ; Molar ; Oral Health ; Prevalence ; Root Caries

OBJECTIVEActinomyces are members of the indigenous oral microbiota which have been implicated in root caries, but their role in childhood caries initiation and progression is not well-understood. The distribution of Actinomyces in supragingival plaque on the primary teeth and the relationship between oral Actinomyces spp. and childhood caries primarily were investigated.

METHODSForty children aged from three to five years old were divided into two groups. Twenty children were caries-free and twenty were caries-susceptible. Dental plaque samples from different places of the teeth were collected with sterile toothpick and polymerase chain reaction was performed with specific primers which were designed for this research.

RESULTSActinomyces spp. were detected 100% in the caries-free group, while 95% in the caries-susceptible group. There was no significant differences between the two groups (P > 0.05). Actinomyces naeslundii, Actinomyces odontolyticus, Actinomyces gerencseriae, Actinomyces israelii and Actinomyces viscosus all could be detected in both groups. The prevalence of Actinomyces naeslundii, Actinomyces gerencseriae and Actinomyces odontolyticus were higher in caries-free group than those in caries-susceptible group (P < 0.05), while the prevalence of Actinomyces israelii and Actinomyces viscosus had no significant difference between the two groups (P > 0.05).

CONCLUSIONActinomyces is the main colonized bacteria in the supragingival plaque of children. The prevalence of the Actinomyces spp. may have a negative relationship with the childhood caries, and has nothing to do with different places of the teeth.

Actinomyces ; Bacteria ; DNA, Bacterial ; Dental Caries ; Dental Plaque ; Humans ; Polymerase Chain Reaction ; Root Caries ; Tooth ; Tooth, Deciduous

PURPOSE: We investigated correlations between the findings of oral examinations and panoramic radiography in order to determine the efficacy of using panoramic radiographs in screening examinations. METHODS: This study included patients who visited dental clinics at National Health Insurance Service (NHIS) Ilsan Hospital for checkups during 2009–2015 and underwent panoramic radiographic examinations within 1 year prior to the oral examinations. Among the 48,006 patients who received checkups, 1,091 were included in this study. The data were evaluated using the Cohen kappa and interrater agreement coefficients. Accuracy, sensitivity, and specificity were calculated using data from the panoramic radiographs as true positive diagnoses. RESULTS: The interrater agreement coefficient for occlusal caries was 28.8%, and the Cohen kappa coefficient was 0.043 between the oral and panoramic radiographic examinations. Root caries and subgingival calculus were only found on the radiographs, while gingival inflammation was found only by the oral examinations. The oral examinations had a specificity for detecting occlusal dental caries of 100%, while their sensitivity for proximal dental caries and supragingival calculus was extremely low (14.0% and 18.3%, respectively) compared to the panoramic radiographic examinations. The oral examinations showed a relatively low sensitivity of 66.2% and a specificity of 43.7% in detecting tooth loss compared with panoramic radiography. CONCLUSIONS: Panoramic radiography can provide information that is difficult to obtain in oral examinations, such as root caries, furcation involvement, and subgingival calculus, which are factors that can directly affect the survival rate of teeth. It therefore seems reasonable and necessary to add panoramic radiography to large-scale health checkup programs such as that provided by the NHIS.
Calculi ; Dental Caries ; Dental Clinics ; Diagnosis ; Diagnosis, Oral ; Humans ; Inflammation ; Mass Screening ; National Health Programs ; Radiography, Dental ; Radiography, Panoramic ; Root Caries ; Sensitivity and Specificity ; Survival Rate ; Tooth ; Tooth Loss

PURPOSE : The purpose of this study was to develop the radiographic technique for detecting the demineralization which is known as indication of dental caries MATERIALS AND METHODS : This technique was based on the comparing of multiple radiographs which was irradiated by multiple X-ray spectra. For the meaningful comparing, the multiple radiographs were reconstructed to the dosimetrically consistent images using a standard material. The difference of resulting images of same target with multiple spectra represents the difference of response of material as regards the spectra. RESULTS : We have found about 10% of demineralization of dental hard tissues particularly in the proximal region through the analyzing of differences. CONCLUSION : Most intriguing thing in this investigation was that the method to analyze difference shows us to an anatomic structure of dental hard tissues even if absolute values of optical density were excluded during the procedures.
Dental Caries

Dental caries is the main oral health problem in hearing-impaired (HI) children and remains the most neglected need. The present study aimed to determine caries prevalence and treatment needs in HI children and the association with salivary parameters. A cross-sectional study was conducted on 63 HI children aged between 7-14 years who attended a special school for the deaf. Clinical oral examination was done and salivary parameters (resting flow rate and resting pH) were measured. Caries experience was charted using the index of decay-filled teeth (dft) and Decay-Missing-Filled Teeth (DMFT) for primary and permanent dentition respectively. Data were analysed using SPSS version 12.0. The mean age was 11.5 (SD 2.39) years and 53.8% were female. Dental caries prevalence was 88.0% (95% Cl: 73.0, 100.0) in primary dentition and 85.0% (95% Cl: 73.0, 96.0) in permanent dentition. The mean dft was 6.1 (SD 4.14) and the mean DMFT was 4.9 (SD 3.28). The mean resting flow rate was 0.14 (SD 0.08) ml/min while mean pH was 6.8 (SD 0.79). Both pit and fissure sealants and restorations were the highest (83.1%) treatment needs. Only 3.1% of the children did not require any treatment. There were no significant association between both salivary flow rate and salivary pH with caries experience in the primary (p=0.342, p=0.610 respectively) and permanent (p= 0.99, p=0.70 respectively) teeth. In conclusion, children with HI have high caries prevalence and unmet need for dental treatments. Salivary pH and resting flow rate of the children were not associated with their caries experience.
Dental caries

This study aimed to assess the nutritional status (BMI), oral health behaviour, sugar consumption and the associated factors with dental caries among a group of 7 to 11 years old children in Kuala Lumpur, Malaysia. Three hundred and twelve students were recruited from February to July 2013. Information gathered were their socio-demographic characteristics, body mass index, sugar consumption, oral-health behaviour, oral hygiene index and decay-missing-filled teeth (dmft) index. Anthropometry measurements and sugar intake was measured using verified tools. Meanwhile, dmft was examined using the World Health Organization (WHO) criteria. 53.7% of the children were of the normal body weight with mean sugar consumption of 31.81±4.24 g/day. Prevalence of dental caries was reported at 44.6% (95% CI: 42.2, 53.3) with a mean (SD) dmft of 1.27(1.84). No association was found between dental caries and weight status distribution. Most children tend to brush their teeth 2 times or more in a day (75%), however, they spent lesser time in tooth brushing (5.4%) and do not practice flossing (78%). Regression analysis showed that age (p<0.001), duration of teeth brushing (p=0.023) and the oral hygiene index (p=0.002) were significant predictors of dental caries among this group of children. Present findings suggest that younger children, longer time taken to brush teeth and poorer oral hygiene index were predisposing factors in dental caries, especially for young children. Hence, education on dental health is important to improve oral health behaviour and oral hygiene practices to further reduce dental caries incidences among young children.
Dental Caries

OBJECTIVETo observe the effect of matrix metalloproteinase-1 (MMP-1) from human host on degradation of dentin organic matrix of root dentin.

METHODSThe freshly extracted caries-free impacted teeth were selected. Teeth were cut transversely under the enamel-cementum junction into dentin sections with a thickness of about 5 mm. Then all sections with removal of cementum, pulp and predentin were randomly divided into four groups. In the first group, dentin sections were demineralized with acid solution for 21 days, and then incubated with MMP-1 solution for 7 days; the second group were only treated with acid solution for 21 days; the third group were only attacked by MMP-1 solution for 7 days; and the fourth group were untreated as a control. Then all sections were dehydrated in ascending strength of alcohol, critically dried, coated with platinum, and then observed under scanning electron microscope(SEM).

RESULTSThe dentin sections of root surface attacked by acid and MMP-1 showed that demineralization of dentin mineral and degradation of dentin matrix fibrae synchronously happened. The dentin matrix fibrae wasn't degradated in the groups treated with acid or MMP-1.

CONCLUSIONThe proteinases from human host may play an important role in the development of root surface caries. MMP-1 may distinctly degradate the organic matrix of demineralized dentin.

Dental Cementum ; Dental Enamel ; Dentin ; enzymology ; Humans ; Matrix Metalloproteinase 1 ; physiology ; Microscopy, Electrochemical, Scanning ; Root Caries ; enzymology ; Tooth Root ; enzymology

PURPOSE: Many clinical studies have reported that higher success rates are achieved with teeth that have immature roots than other autotransplanted teeth that have more immature root. However, based on date published recently, the success rate of autotransplantation of teeth with complete root formation was higher. The purpose of this study was to examine the long term(2 to 6 years follow-up) success rate of autotransplantation of third molar with complete root formation and to discuss some conditions and prerequisites for success. MATERIALS AND METHODS: 26 sites of 24 patients aged 26 to 55 (mean age 40.8) were autotransplanted with third molars with complete root formation. These cases were followed for 2 to 6 years after surgery. The success criteria included (1) no discomfort during functioning (2) absence of progressive root resorption and alveolar bone resorption. RESULT: Of 26 teeth 5 teeth were failed, therefore success rate is 81%(21/26 teeth). The results suggested that higher success rate is acquired from (1) extraction socket due to dental caries (2) mandibular recipient site (3) patient younger than 40 years old. Autotransplantation of third molar to replace molars with advanced periodontal disease also showed considerably high success rate(84%). CONCLUSION: With appropriate case selection, autotransplantation of third molar with complete root formation remains a viable alternative for replacing a missing molar tooth.
Aged ; Dental Caries ; Humans ; Molar ; Molar, Third ; Periodontal Diseases ; Root Resorption ; Tooth