A prediction model for periodontal disease: modelling and validation from a National Survey of 4061 Taiwanese adults

Microbiome of periodontitis and peri-implantitis before and after therapy: Long-read 16S rRNA gene amplicon sequencing

AIMS

The microbial profiles of peri-implantitis and periodontitis (PT) are inconclusive. The controversies mainly arise from the differences in sampling sites, targeted gene fragment, and microbiome analysis techniques. The objective of this study was to explore the microbiomes of peri-implantitis (PI), control implants (CI), PT and control teeth (CT), and the microbial change of PI after nonsurgical treatment (PIAT).

METHODS

Twenty-two patients diagnosed with both PT and peri-implantitis were recruited. Clinical periodontal parameters and radiographic bone levels were recorded. In each patient, the subgingival and submucosal plaque samples were collected from sites with PI, CI, PT, CT, and PIAT. Microbiome diversity was analyzed by high-throughput amplicon sequencing using full-length of 16S rRNA gene by next generation sequencing.

RESULTS

The 16S rRNA gene sequencing analysis revealed 512 OTUs in oral microbiome and 377 OTUs reached strain levels. The PI and PT groups possessed their own unique core microbiome. Treponema denticola was predominant in PI with probing depth of 8-10 mm. Interestingly, Thermovirga lienii DSM 17291 and Dialister invisus DSM 15470 were found to associate with PI. Nonsurgical treatment for peri-implantitis did not significantly alter the microbiome, except Rothia aeria.

CONCLUSION

Our study suggests Treponemas species may play a pivotal role in peri-implantitis. Nonsurgical treatment did not exert a major influence on the peri-implantitis microbiome in short-term follow-up. PT and peri-implantitis possess the unique microbiome profiles, and different therapeutic strategies may be suggested in the future.

Data-driven prediction model for periodontal disease based on correlational feature analysis and clinical validation

Objectives

This study aimed to investigate the performance and reliability of data-driven models employing correlational feature analysis and clinical validation for predicting periodontal disease.

Methods

The 7th Korea National Health and Nutrition Examination Survey (n = 10,654) was used for correlation analysis to identify significant risk factors for periodontitis. Periodontal prediction models were developed with the selected factors and database, followed by internal validation with 5-fold cross-validation and 1000 bootstrap resampling. External validation was conducted with clinical data (n = 120) collected through self-reported questionnaires, clinical periodontal parameters, and radiographic image analysis. Predictive performance was assessed for logistics regression, support vector machine, random forest, XGBoost, and neural network algorithms using the area under the receiver operating characteristic curves (AUC) and other performance metrics.

Results

Correlation analysis identified 16 features from over 1000 potential risk factors for periodontitis. The best data-driven model (XGBoost) showed AUC values of 0.823 and 0.796 for internal and external validations, respectively. Modeling with clinical data revealed those same measures to be 0.836 and 0.649, respectively. In addition, the data-driven model could predict other clinical periodontal parameters including severe bone loss (AUC = 0.813), gingival bleeding (AUC = 0.694), and tooth loss (AUC = 0.734). A patient case study about prognostic predictions revealed that the probability of periodontitis can be reduced by 6.0 % (stop smoking) and 0.6 % (stop drinking) on average.

Conclusions

Data-driven models for predicting periodontitis and other periodontal parameters were developed from 16 risk factors, demonstrating enhanced prediction performance and reproducibility in internal-external validations.

Development of Risk Prediction Models for Severe Periodontitis in a Thai Population: Statistical and Machine Learning Approaches

BACKGROUND

Severe periodontitis affects 26% of Thai adults and 11.2% of adults globally and is characterized by the loss of alveolar bone height. Full-mouth examination by periodontal probing is the gold standard for diagnosis but is time- and resource-intensive. A screening model to identify those at high risk of severe periodontitis would offer a targeted approach and aid in reducing the workload for dentists. While statistical modelling by a logistic regression is commonly applied, optimal performance depends on feature selections and engineering. Machine learning has been recently gaining favor given its potential discriminatory power and ability to deal with multiway interactions without the requirements of linear assumptions.

OBJECTIVE

We aim to compare the performance of screening models developed using statistical and machine learning approaches for the risk prediction of severe periodontitis.

METHODS

This study used data from the prospective Electricity Generating Authority of Thailand cohort. Dental examinations were performed for the 2008 and 2013 surveys. Oral examinations (ie, number of teeth and oral hygiene index and plaque scores), periodontal pocket depth, and gingival recession were performed by dentists. The outcome of interest was severe periodontitis diagnosed by the Centre for Disease Control-American Academy of Periodontology, defined as 2 or more interproximal sites with a clinical attachment level ≥6 mm (on different teeth) and 1 or more interproximal sites with a periodontal pocket depth ≥5 mm. Risk prediction models were developed using mixed-effects logistic regression (MELR), recurrent neural network, mixed-effects support vector machine, and mixed-effects decision tree models. A total of 21 features were considered as predictive features, including 4 demographic characteristics, 2 physical examinations, 4 underlying diseases, 1 medication, 2 risk behaviors, 2 oral features, and 6 laboratory features.

RESULTS

A total of 3883 observations from 2086 participants were split into development (n=3112, 80.1%) and validation (n=771, 19.9%) sets with prevalences of periodontitis of 34.4% (n=1070) and 34.1% (n=263), respectively. The final MELR model contained 6 features (gender, education, smoking, diabetes mellitus, number of teeth, and plaque score) with an area under the curve (AUC) of 0.983 (95% CI 0.977-0.989) and positive likelihood ratio (LR+) of 11.9 (95% CI 8.8-16.3). Machine learning yielded lower performance than the MELR model, with AUC (95% CI) and LR+ (95% CI) values of 0.712 (0.669-0.754) and 2.1 (1.8-2.6), respectively, for the recurrent neural network model; 0.698 (0.681-0.734) and 2.1 (1.7-2.6), respectively, for the mixed-effects support vector machine model; and 0.662 (0.621-0.702) and 2.4 (1.9-3.0), respectively, for the mixed-effects decision tree model.

CONCLUSIONS

The MELR model might be more useful than machine learning for large-scale screening to identify those at high risk of severe periodontitis for periodontal evaluation. External validation using data from other centers is required to evaluate the generalizability of the model.

Systematic comparison of machine learning algorithms to develop and validate predictive models for periodontitis

AIM

The aim of this study was to compare the validity of different machine learning algorithms to develop and validate predictive models for periodontitis.

MATERIALS AND METHODS

Using national survey data from Taiwan (n = 3453) and the United States (n = 3685), predictors of periodontitis were extracted from the datasets and pre-processed, and then 10 machine learning algorithms were trained to develop predictive models. The models were validated both internally (bootstrap sampling) and externally (alternative country's dataset). The algorithms were compared across six performance metrics ([i] area under the curve for the receiver operating characteristic [AUC], [ii] accuracy, [iii] sensitivity, [iv] specificity, [v] positive predictive value, and [vi] negative predictive value) and two methods of data pre-processing ([i] machine-learning-based feature selection and [ii] dimensionality reduction into principal components).

RESULTS

Many algorithms showed extremely strong performance during internal validation (AUC > 0.95, accuracy > 95%). However, this was not replicated in external validation, where predictive performance of all algorithms dropped off drastically. Furthermore, predictive performance differed according to data pre-processing methodology and the cohort on which they were trained.

CONCLUSIONS

Larger sample sizes and more complex predictors of periodontitis are required before machine learning can be leveraged to its full potential.

Community-based multiple screening for metabolic syndrome by innovative theory: A longitudinal study

The purpose of this research is to elucidate whether metabolic syndrome affects the rate of adoption of a new multiple cancer screening programme, based on the Diffusion of Innovation theory. The time to attend the screening programme, conducted in Keelung, Taiwan, within 10 years was assessed by innovativeness (innovators, early adaptors, early majority, late majority and laggard) using data from 79,303 residents, with the information on metabolic syndrome accrued from routine adult health check-ups. The median time of adopting the programme and the relative rates of early adoption by metabolic syndrome and its severity score were estimated. The results show that the estimated times to adopt the programme ranged from 3 months for innovators to 10 years for the laggard. The rate of early adoption was 34% higher for participants without metabolic syndrome than for those with the disease, and the gradient relationship of disease severity was noted. The adjusted median time to adopt innovativeness was 0.82 years earlier for participants who were disease-free than those with the disease. Meanwhile, the adjusted median time was wider by up to 2.25 years for those with severe disease. The study suggests that innovation should prioritise the potential risk of the metabolic syndrome population.

Recommendations for treating stage I-III periodontitis in the Taiwanese population: A consensus report from the Taiwan Academy of Periodontology

BACKGROUND/PURPOSE

Based on the fundamental of the S3-level clinical practice guideline (CPG) for treating stage I-III periodontitis developed by the European Federation of Periodontology (EFP), this consensus report aimed to develop treatment recommendations for treating periodontitis in the Taiwanese population.

METHODS

The report was constructed by experts from the Taiwan Academy of Periodontology. The following topics were reviewed: (a) the prevalence of periodontitis in Asia and current status of treatment in Taiwan; (b) specific anatomical considerations for treating periodontitis in Asians; (d) educational and preventive interventions and supragingival plaque control; (d) subgingival instrumentation and adjunctive treatment; (e) surgical periodontal therapy; and (f) maintenance and supportive periodontal care. Recommendations were made according to the evidences from the EFP CPG, the published literature and clinical studies in Asians, and the expert opinions.

RESULTS

The treatment recommendations for the Taiwanese population were generally in parallel with the EFP CPG, and extra cautions during treatment and maintenance phases were advised due to the anatomical variations, such as shorter root trunk, higher prevalence of supernumerary distolingual root and lingual bony concavity in mandibular posteriors, and thinner anterior labial plate, of the Asian population.

CONCLUSION

The EFP CPG could be adopted for treating periodontitis and maintaining periodontal health of the Taiwanese population, and anatomical variations should be cautious when the treatment is delivered.

Greater inequalities in dental caries treatment than in caries experience: a concentration index decomposition approach

Background

The aim of the current study was to (a) measure the socioeconomic inequalities in oral health and examine whether the inequalities are greater in disease experience or in its treatment and to (b) decompose the factors that influence oral health inequalities among the adults of Guangdong Province.

Methods

A cross-sectional study was conducted among 35- to 44-year-old and 65- to 74-year-old adults in Guangdong Province. All participants underwent oral health examinations and answered questionnaires about their oral health. We measured the concentration indices of the DMFT and its separate components, namely, decayed teeth (DT), missing teeth (MT), and filled teeth (FT), to explore the inequalities in oral health status; then, we analysed its decomposition to interpret the factors that influence the inequalities.

Results

The results showed that significant inequality was concentrated on FT (CI =  0.24, 95% CI = 0.14/0.33, SE = 0.05). The concentration indices for the DMFT (CI =  0.02, 95% CI =  0.02/0.06, SE = 0.02) and MT (CI =  0.02, 95% CI 0.03/0.08, SE = 0.03) were small and close to zero, while the concentration for DT (CI =  − 0.04, 95% CI =  − 0.01/0.02, SE = 0.03) was not statistically significant. The results from the decomposition analysis suggested that a substantial proportion of the inequality was explained by household income, high education level, regular oral examination and type of insurance (5.1%, 12.4%, 43.2%, − 39.6% (Urban Employee Basic Medical Insurance System) and 34.5% (New-Type Rural Medical Collaboration System), respectively).

Conclusions

The results indicated greater inequalities in dental caries than in caries experience. Among the included factors, household income, high education level, and regular oral health examinations had the greatest impact on the inequalities in the number of FT. In addition, the current medical insurance systems, including the Urban Employee Basic Medical Insurance System, Urban Resident Basic Medical Insurance System, and the New-Type Rural Medical Collaboration System, have not been effectively used in oral treatment. Policy-making and the implementation of interventions for tackling socioeconomic oral health inequalities should focus on reducing the burden of treatment and providing greater access to dental care for low-income groups. Welfare policies are skewed towards rural areas and low-income people.

Prevalence of Dental Caries and Periodontal Disease of High School Students Aged 15 to 18 Years in Taiwan

The purpose of this study was to assess the prevalence and distribution of dental caries and periodontal disease in Taiwanese high school students aged 15–18. A total of 1069 Taiwanese students participated in a cross-sectional nationwide dental survey. By using a stratified method based on the National Health Insurance administration regions, 24 high schools were randomly sampled in different areas of Taiwan. The participants were examined with dental mirrors and community periodontal index (CPI) probes without using radiographs, to measure dental caries and periodontal status. Demographic information and other relevant risk indicators for the two diseases were gathered via a self-report questionnaire. In this study population, the weighted mean decayed, missing and filled teeth (DMFT) scores for ages 15 to 18 were 5.2, 6.1, 6.1, and 5.7. The weighted mean decayed, missing and filled surfaces (DMFS) scores were 9.0, 12.0, 13.1, and 11.2 at ages 15, 16, 17, and 18, respectively. Additionally, 88.2% of the subjects had periodontal disease, with calculus as the most prevalent type. Moreover, 5.2% of these students showed loss of attachment. There was no significant association between dental caries and periodontal disease. Dental caries and periodontal disease were prevalent among Taiwanese high school students in this national dental survey.

Effectiveness of a 30-year periodontist's primary care for 1946 patients during five-year follow-up

OBJECTIVE

To evaluate the effect of the periodontal primary care (PPC) on the improvement of periodontal probing depth based on a periodontist's 30-year practice.

MATERIALS AND METHODS

We enrolled a total of 2,894 patients who underwent periodontal basic treatment between 1987 and 2017 with 84.5% retention rate. The study population was composed of 80% (n = 1,946) of retained patients with complete re-evaluation up to five-year follow-up. The outcome was measured by the improvement of probing depths (graded as 1:1-3 mm; 2:4-6 mm; 3: ≥7 mm) before and after PPC on both sextant and patient levels. Whether a better improvement was seen in the surgical group and the non-smoker group opposed to their comparators was assessed with various multi-variable regression models.

RESULTS

On patient (sextant) level, 82% (38%) improved, 13% (59%) unchanged, and 5% (3%) deteriorated. Adjusted better improvement of probing depth was noted for the surgical group by 63% and non-smoker by 31% compared with their counterparts. The similar findings were found for the outcomes based on continuous probing depth scores.

CONCLUSIONS

We demonstrate the improvement of probing depth scores with a periodontal primary care offered for the retained patients and larger effect for the surgical group and non-smoker patients.

Association between periodontitis and all-cause and cancer mortality: retrospective elderly community cohort study

BACKGROUND

Periodontal infection induces inflammation, which may increase the risk of tumor-promoting effects. The aim of this study was to assess the association between periodontitis and all-cause mortality, and all-cancer and specific cancers' mortality in a health examination cohort of the elderly in the communities.

METHODS

A dataset of health examinations for the elderly with cause of death from 2005 to 2012 was obtained from the Department of Health, Taipei City Government. We enrolled 82,548 study participants with 262,035 visits. A Cox proportional hazards model and Cox frailty model were used for calculating the hazard ratios under different periodontal status by using SAS and Rstudio.

RESULTS

Being male, elderly, having a low education level, and smoking were risk factors for mortality in this retrospective elderly community cohort study. Participants with periodontitis followed across time had significantly higher hazard ratios (HRs) for all-cause mortality and all-cancer mortality (HR = 1.092, 95% confidence interval (CI):1.038 to 1.149, HR = 1.114, 95% CI:1.032 to 1.203, respectively) in the Cox frailty models after adjusting for age, marital status, education level, sex, and smoking status. After adjusting for age and sex, the hazard ratio was 1.185 (95% CI: 1.027 to 1.368) for lung cancer mortality, and 1.340 (95% CI: 1.019 to 1.762) for prostate cancer mortality in the periodontitis group with each visit.

CONCLUSIONS

The findings indicated that being male, having a low education level, and daily smoking were risk factors for mortality, and showed mixed evidence that periodontal disease is associated with all-cause, all-cancer and specific-cancer mortality including lung and prostate cancer. We suggest the importance of regular health screening in order to achieve early disease detection and lower mortality risk.

Gingival bleeding and calculus among 12-year-old Chinese adolescents: a multilevel analysis

BACKGROUND

Gingivitis is a common oral health problem, and untreated gingivitis can progress to periodontitis. The objectives of this study were to (1) explore associated factors of gingival bleeding and calculus among 12-year-old adolescents; (2) find predictive models for gingivitis management.

METHODS

Four thousand five hundred twenty-five subjects aged 12 in Sichuan Province were investigated. The questionnaire and clinical examination were applied in schools, and two-level logistic regression models were constructed to interpret the effect of individual and contextual factors on Chinese adolescents' gingival bleeding and calculus.

RESULTS

46.63% (95%CI: 40.71, 51.60) and 66.94% (95%CI: 56.85, 67.45) of the subjects presented gingival bleeding and calculus, respectively. For the gingival bleeding cases, the model showed the significant associated indicators were hukou (OR = 0.61, 95% CI: 0.52-0.72), family size (OR = 1.41, 95% CI: 1.19-1.68), parental educational level (father: OR = 0.53, 95% CI: 0.45-0.63; mother: OR = 0.71, 95% CI: 0.59-0.86), tooth-brushing frequency (OR = 0.35, 95% CI: 0.26-0.48), dental floss use (OR = 0.58, 95% CI: 0.41-0.83), sugar-containing drink consumption (OR = 2.11, 95% CI: 1.80-2.49), and dental visit (OR = 1.44, 95% CI: 1.19-1.74). It also confirmed that gender (OR = 1.32, 95% CI: 1.13-1.54), hukou (OR = 0.69, 95% CI: 0.59-0.82), family size (OR = 1.34, 95% CI: 1.12-1.59), parental educational level (father: OR = 0.46, 95% CI: 0.39-0.54; mother: OR = 0.65, 95% CI: 0.59-0.82), tooth-brushing frequency (OR = 0.57, 95% CI: 0.42-0.78), dental floss use (OR = 0.66, 95% CI: 0.48-0.90) and sugar-containing drink consumption (OR = 1.30, 95% CI: 1.11-1.53) were associated factors for dental calculus.

CONCLUSIONS

Gingival bleeding and calculus were common in western Chinese adolescents. Socio-demographic factors including gender, hukou and family factors are strong determinants of gingival health in Chinese adolescents. In addition, health-related lifestyle behaviors such as healthy diet, good hygiene care and more dental visits are good predictors of better gingival status.

Prevalence and associated factors of periodontal conditions among 55- to 74-year-old adults in China: results from the 4th National Oral Health Survey

OBJECTIVE

The purpose of this study was to assess periodontal health conditions among 55- to 74-year-old Chinese people and to analyze the factors associated with periodontal diseases.

MATERIALS AND METHODS

In total, 9054 subjects aged 55-74 years were enrolled from all 31 provinces using a stratified multistage probability sampling method, autonomous regions and municipalities of the Chinese mainland, the response rate was 86.9%. All subjects underwent clinical examinations on the severest site for every tooth and completed a questionnaire that collected information on their sociodemographic characteristics and oral habits. T tests, chi-square tests and binary logistic regression analysis were performed to analyze the data.

RESULTS

The percentage of people without bleeding on probing, probing depth ≥ 4 mm and attachment loss > 3 mm was 5.0 and 9.3% in the 55- to 64-year-old and the 65- to 74-year-old age group. The prevalence of bleeding on probing was 88.4% among 55 to 64 years old and 82.6% among 65 to 74 years old. Mean number of teeth with bleeding on probing were 13.87 among 55 to 64 years old and 11.25 among 65 to 74 years old. The prevalence of probing depth ≥ 4 mm and attachment loss > 3 mm were 69.3 and 69.9% in people aged 55-64 years and were 64.6 and 74.2% in people aged 65-74 years. Mean number of teeth with probing depth = 4-5 mm and probing depth ≥ 6 mm were 4.48 and 0.36 in 55-64 age group and 3.70 and 0.33 in 65-74 age group. And mean number of teeth with attachment loss > 3 mm were 5.17 among 55 to 64 years old and 5.63 among 65 to 74 years old. Besides, attachment loss > 3 mm was associated with age, gender, smoking, toothbrushing frequency and toothpick use.

CONCLUSIONS

Periodontitis was not highly prevalent among 55- to 74-year-old Chinese adults. Age, gender, smoking, toothbrushing frequency and toothpick use could be risk factors.

CLINICAL RELEVANCE

Scientific rationale for the study: The periodontal conditions among 55 to 64 and 65 to 74 years old Chinese population were not highly serious, but prevalence of bleeding on probing, periodontal pockets and attachment loss should be drawn enough attention by relevant public health administrations.

PRINCIPAL FINDINGS

The prevalence of periodontal diseases was evaluated in 55- to 64-year-old and 65- to 74-year-old subjects in a nationally representative Chinese sample population. The prevalence of probing depth ≥ 4 mm and AL > 3 mm were high; these values were 69.3% and 69.9%, respectively, in the 55-64 age group and 64.6% and 74.2%, respectively, in the 65-74 age group. In addition, case percentage of AL = 4-5 mm combined with PD < 6 mm were 23.1 and 19.4% among 55- to 64-year-old and 65- to 74-year-old people. And case percentage of AL> 5 mm combined with PD ≥ 6 mm were 11.1% and 12.1% among 55- to 64-year-old and 65- to 74-year-old people, respectively.

PRACTICAL IMPLICATIONS

The present study provides a reference for the epidemiological analysis of periodontal diseases. To reduce widespread inadequate treatment of periodontal diseases, clinical management should be performed in dental practices. Furthermore, oral health recommendations should be made at multiple levels.

Influence of Adjacent Teeth Absence or Extraction on the Outcome of Non-Surgical Periodontal Therapy

Background: Extraction of periodontally compromised or strategically non-important teeth is often an integral part of non-surgical periodontal treatment (NSPT). This study evaluated the association between the status of adjacent teeth and the outcome of NSPT on molars. Methods: Charting data of patients with generalized chronic periodontitis receiving NSPT in 2012–2014 were included. The association between initial clinical parameters and significant clinical improvement, including the reductions of probing pocket depth (PPD) and clinical attachment loss (CAL), in molar teeth with severe periodontitis after NSPT was assessed by a generalized linear model and logistic regression. Results: ≥7 mm PPD and <2 mm gingival recession (REC) at the tooth level, and ≥7 mm PPD, ≥7 mm CAL and <2 mm REC at the site level, were associated with significant clinical improvement. Absence or extraction of an adjacent tooth achieved an additional 0.22–0.23 mm and 0.60–0.83 mm clinical improvement. Among the interproximal sites, ≥7 mm PPD, <2 mm REC, ≥7 mm CAL, <Degree II furcation involvement, and absence of an adjacent tooth were associated with significant clinical improvement. Conclusion: Absence or extraction of teeth during NSPT significantly improves the PPD and CAL of the adjacent periodontal sites of molars.

Trends in the prevalence of periodontitis in Taiwan from 1997 to 2013: A nationwide population-based retrospective study

Periodontitis is one of the most prevalent oral diseases. In this study, we probed the nationwide registered database to assess the time trends of prevalence of periodontitis in Taiwan.A retrospective study was conducted to analyze the registered database compiled by the National Health Insurance provided by the Department of Health, Taiwan, from 1997 to December 2013.We found that the prevalence of periodontitis significantly increased from 11.5% in 1997 to 19.59% in 2013 (P for trend < .0001). The mean age ± standard deviation with periodontitis from 1997 to 2013 was 54.46 ± 14.47 and 45.51 ± 16.58 years old, respectively. The proportion of individuals with periodontitis in age group >65 years old decreased markedly. The proportion of individuals with periodontitis in age groups <25 and 26 to 35 years old demonstrated an increased pattern. Compared to the reference cohort of 1953 to 1957, the recent birth cohort of 1993 to 1997 revealed the highest relative risk (RR) of periodontitis (male: RR, 67.42, 95% confidence interval [CI], 17.04-266.76; female: RR, 65.85, 95% CI, 16.70-259.70). Both male and female groups showed the similar age-effect pattern in the cross-sectional age curve from age-period-cohort model. There was an upturn with advancing age up to 40 to 50 years old and then a downward trend in both genders. Population dwelling in suburban area (RR, 0.95; 95% CI, 0.94-0.97) and rural area (RR, 0.97; 95% CI, 0.95-0.99) had the lower risk of periodontitis than those who lived in urban area. The higher income group revealed the higher risk of periodontitis compared with lower income group (RR, 1.20; 95% CI, 1.18-1.23).The prevalence of periodontitis significantly increased in Taiwan over past 17 years. The mean age with periodontitis was shown in a decreased pattern. The use of a nationwide population-based database could provide sufficient sample size, generalizability, and statistical power to assess the periodontal status in Taiwan.

Development and validation of a risk prediction model for end-stage renal disease in patients with type 2 diabetes

The aim of this study is to develop a prediction model for ESRD in patients with type 2 diabetes. A retrospective cohort study was conducted, consisting of 24,104 Chinese patients with type 2 diabetes. We adopted the procedures proposed by the Framingham Heart Study to develop a prediction model for ESRD. Participants were randomly assigned to the derivation and validation sets at a 2:1 ratio. The Cox proportional hazard regression model was used for model development. A total of 813 and 402 subjects (5.06% and 5.00%, respectively) developed ESRD in the derivation and validation sets over a mean follow-up period of 8.3 years. The risk-scoring systems included age, gender, age of diabetes onset, combined statuses of blood pressure and anti-hypertensive medication use, creatinine, variation in HbA1c, variation in systolic blood pressure, diabetes retinopathy, albuminuria, anti-diabetes medications, and combined statuses of hyperlipidemia and anti-hyperlipidemia medication use. The area under curves of 3-year, 5-year, and 8-year ESRD risks were 0.90, 0.86, and 0.81 in the derivation set, respectively. This risk score model can be used as screening for early prevention. The risk prediction for 3-year, 5-year, and 8-year period demonstrated good predictive accuracy and discriminatory ability.

Modulation of periodontitis progression using pH-responsive nanosphere encapsulating metronidazole or N-phenacylthialzolium bromide

BACKGROUND AND OBJECTIVE

This study aimed to develop pH-responsive polylactide-glycolic acid co-polymer and chitosan (PLGA/chitosan) nanosphere as an inflammation-responsive vehicle and evaluate the potential of the nanosphere encapsulating metronidazole, an antibiotic, and N-phenacylthiazolium bromide (PTB), a host modulator, for treating periodontitis.

MATERIAL AND METHODS

PLGA/chitosan nanospheres were fabricated using oil-in-water emulsion method. Experimental periodontitis was induced on the rat maxillae, and the sites were randomly allocated to four treatment categories, including periodontitis alone (PR), periodontitis with nanospheres alone, nanospheres encapsulating metronidazole (MT) and nanospheres encapsulating PTB (PB). The ligature was retained until the animals were killed, and the treatment outcome was evaluated by the progression of periodontal bone loss (PPBL), inflammatory cell infiltration and collagen deposition.

RESULTS

The encapsulated drug was released rapidly from the nanospheres without significant initial burst release at pH 5.5. Compared with group PR, PPBL was significantly reduced in groups MT and PB on day 4 (P<.05). On day 21, PPBL was significantly lower in group PB (P<.05). In groups MT and PB, inflammation was significantly reduced in groups MT and PB relative to groups PR and periodontitis with nanospheres alone (P<.05), and collagen deposition was significantly greater relative to group PR (P<.05).

CONCLUSION

PLGA/chitosan nanospheres encapsulating metronidazole or PTB showed potential for modulating periodontitis progression.

PDGF-metronidazole-encapsulated nanofibrous functional layers on collagen membrane promote alveolar ridge regeneration

This study aimed to develop a functionally graded membrane (FGM) to prevent infection and promote tissue regeneration. Poly(l-lactide-co-d,l-lactide) encapsulating platelet-derived growth factor (PDLLA-PDGF) or metronidazole (PDLLA-MTZ) was electrospun to form a nanofibrous layer on the inner or outer surface of a clinically available collagen membrane, respectively. The membrane was characterized for the morphology, molecule release profile, in vitro and in vivo biocompatibility, and preclinical efficiency for alveolar ridge regeneration. The PDLLA-MTZ and PDLLA-PDGF nanofibers were 800–900 nm in diameter, and the thicknesses of the functional layers were 20–30 μm, with sustained molecule release over 28 days. All of the membranes tested were compatible with cell survival in vitro and showed good tissue integration with minimal fibrous capsule formation or inflammation. Cell proliferation was especially prominent on the PDLLA-PDGF layer in vivo. On the alveolar ridge, all FGMs reduced wound dehiscence compared with the control collagen membrane, and the FGM with PDLLA-PDGF promoted osteogenesis significantly. In conclusion, the FGMs with PDLLA-PDGF and PDLLA-MTZ showed high biocompatibility and facilitated wound healing compared with conventional membrane, and the FGM with PDLLA-PDGF enhanced alveolar ridge regeneration in vivo. The design represents a beneficial modification, which may be easily adapted for future clinical use.

Effects of risk factors on periodontal disease defined by calibrated community periodontal index and loss of attachment scores

OBJECTIVES

We evaluated whether and how the effects of risk factors on periodontal disease (PD) were modified by measurement errors using community periodontal index (CPI) and loss attachment (LA) in the community-based survey.

METHODS

A pilot validation study was performed to estimate the rates of false negative and false positive for both CPI and LA in 31 subjects from different regions using measurements from 12 well-trained dentists and a senior periodontist as a gold standard. Afterward, a Taiwanese nationwide survey was conducted by enrolling 3,860 participants to estimate the effect of each risk factor on PD calibrated with both sensitivity and specificity of two indices.

RESULTS

The values obtained for the sensitivity to false-positive ratio for CPI ranged widely from 1.12 to 7.71, indicating regional variation in both errors. The calibrated adjusted odds ratio for smoking vs non-smoking was higher than the uncalibrated odds ratio for PD defined by CPI (2.75 (2.01, 3.77) vs 2.02 (1.63, 2.52)) and LA (3.85 (2.44, 6.13) vs 1.93 (1.47, 2.54)) scores. Similar underestimation was noted for other risk factors.

CONCLUSION

The effects of risk factors on PD measured using CPI and LA in a large population-based survey were underestimated without correcting for measurement errors.

Oral health status in Sichuan Province: findings from the oral health survey of Sichuan, 2015-2016

To investigate oral health status in the residents of Sichuan Province, southwest China, a cross-sectional study was performed using the latest Oral Health Survey Basic Methods recommended by the World Health Organization. A multistage stratified random cluster-sampling method was used to enroll participants from the following three groups: children aged 3-5 years, adolescents aged 12 years, and people aged 65-74 years. In these three groups, the mean numbers of teeth that were affected by caries were 3.28, 0.86 and 5.13, respectively, resulting in a prevalence of 63.47%, 37.20% and 83.20%, respectively. Relative to the high rate of decayed teeth, the prevalence of fillings was very low in all age groups (0.97%, 7.24% and 5.43%, respectively). In the 12-year-old adolescent group, only 3.61% had good pit and fissure sealing. In addition, the rate of dental fluorosis was 24.80%, and the Community Fluorosis Index value was 0.39. In the elder group, the community periodontal index was 2.92. The prevalence in the elderly of having lost at least one tooth was 75.54%. Additionally, 4.44% of these participants were edentulous. The incidence of dental prosthesis was 51.75%, the proportion with a removable partial denture, a fixed denture, full dentures, dental implants and an informal fixed bridge was 21.59%, 11.45%, 4.64%, 0 and 16.67%, respectively. In this study, 8.2% of the elderly participants were affected by different types of oral mucosal lesions. Among such lesions, recurrent aphthous ulcers were most prevalent (2.69%) and oral lichen planuses were second (1.6%). The conclusion presented in this survey is that oral diseases, especially dental caries and periodontal disease, are frequent and common in Sichuan province, China. Moreover, the treatment rate is very low, and primary prevention and treatment options are therefore urgently needed in this population.

Chronic Periodontitis Is Associated With Spinal Dysmobility in Patients With Ankylosing Spondylitis

BACKGROUND

Although microbes have been suggested to play a role in the pathogenesis of ankylosing spondylitis (AS), several studies present contradictory results regarding the association between AS and chronic periodontitis (CP).

METHODS

Clinical, laboratory, and medication data were collected from 84 patients with AS and 84 age- and sex-matched controls. Periodontal measurements, including probing depths (PDs), clinical attachment loss (AL), serum anti-Porphyromonas gingivalis titers, and the detection of P. gingivalis DNA in gingival crevicular fluid, were recorded. All participants with periodontitis with PD ≥4 to <7 mm received scaling and root planing and were re-evaluated at 12 weeks; those still exhibiting periodontitis with PD of ≥4 to <7 mm at 12 weeks were followed at 24 weeks.

RESULTS

The prevalence of moderate-to-severe CP was not different between patients with AS and controls (70.2% versus 66.6%). The P. gingivalis detection rate was not different between patients with AS and controls or between patients with AS receiving and not receiving anti-tumor necrosis factor (TNF)-α agents. However, CP was positively associated with impaired spinal mobility of patients with AS in multivariate analyses. After periodontal treatment, PD and AL levels were improved in both groups, but the change was significantly greater in patients with AS than in controls. Patients with AS receiving anti-TNF-α agents exhibited a greater improvement in PD and AL than those who did not.

CONCLUSIONS

Although AS was not associated with the presence of CP, CP was associated positively with the severity of spinal dysmobility in Korean patients with AS. These results suggest that periodontitis can have a negative effect on axial movement in AS.