Serum lipoprotein subfractions are associated with the periodontal status: Results from the population-based cohort SHIP-TREND

AIM

To investigate the medium-term associations of serum protein subfractions derived from proton nuclear magnetic resonance (1 H-NMR) spectroscopy with periodontitis and tooth loss.

MATERIALS AND METHODS

A total of 3031 participants of the cohort Study of Health in Pomerania (SHIP-TREND) were included. In addition to conventional serum testing, serum lipoprotein contents and subfractions were analysed by 1 H-NMR spectroscopy. Confounder-adjusted associations of lipoprotein variables with periodontitis and the number of missing teeth variables were analysed using mixed-effects models with random intercepts for time across individuals, accounting for multiple testing.

RESULTS

While only spurious associations between lipoprotein levels from conventional blood tests were found-that is, triglycerides were associated with mean clinical attachment level (CAL) and low-density lipoprotein cholesterol/high-density lipoprotein cholesterol (LDL-C/HDL-C) ratio with the number of missing teeth - several associations emerged from serum lipoprotein subfractions derived from 1 H-NMR analysis. Specifically, elevated LDL triglycerides were associated with higher levels of mean probing depth (PD), mean CALs, and increased odds of having <20 teeth. HDL-4 cholesterol levels were inversely associated with mean PD. Systemic inflammation (C-reactive protein) might mediate the effects of LDL and HDL triglyceride contents on periodontitis severity.

CONCLUSIONS

Several associations between serum lipoprotein subfractions and periodontitis were observed. As the underlying biochemical mechanisms remain unclear, further research is needed.

Interdental cleaning aids are beneficial for oral health at 7-year follow-up: Results from the Study of Health in Pomerania (SHIP-TREND)

AIM

To estimate association between the use of interdental cleaning aids (IDAs) and type on 7-year follow-up levels of interdental plaque, interdental gingival inflammation, interdental periodontitis severity, the number of interdental sound surfaces and the number of missing teeth in a population-based cohort study.

MATERIALS AND METHODS

We used 7-year follow-up data of 2224 participants from the Study of Health in Pomerania (SHIP-TREND). We applied generalized linear and ordinal logistic models, adjusting for confounding and selection bias using inverse probability treatment weighting and multiple imputation.

RESULTS

Flossers were 32% less likely to have higher interdental plaque (iPlaque) levels than non-users of IDAs (odds ratio [OR] = 0.68; 95% confidence interval [CI]: 0.50-0.94); flossing resulted in 5% lower means of iPlaque. Effects on interdental bleeding on probing (iBOP), mean interdental probing depths and mean interdental clinical attachment levels were direction-consistent but statistically non-significant. Interdental brushing was associated with lower follow-up levels for interdental plaque (OR = 0.73; 95% CI: 0.57-0.93) and iBOP (OR = 0.69; 95% CI: 0.53-0.89). IDAs were more effective in reducing iPlaque in participants with periodontitis, whereas iBOP reduction was more pronounced in participants with no or mild periodontitis. The analyses did not suggest that the use of IDAs affected caries. Finally, applying change score analyses, flossing reduced tooth loss incidence (incidence rate ratio [IRR] = 0.71) compared with non-users of IDAs.

CONCLUSIONS

Recommending flossing and interdental brushing in dental practices represents an approach to the prevention of gingivitis and consequently periodontitis.

Alternative splicing analysis benchmark with DICAST

Alternative splicing is a major contributor to transcriptome and proteome diversity in health and disease. A plethora of tools have been developed for studying alternative splicing in RNA-seq data. Previous benchmarks focused on isoform quantification and mapping. They neglected event detection tools, which arguably provide the most detailed insights into the alternative splicing process. DICAST offers a modular and extensible framework for analysing alternative splicing integrating eleven splice-aware mapping and eight event detection tools. We benchmark all tools extensively on simulated as well as whole blood RNA-seq data. STAR and HISAT2 demonstrated the best balance between performance and run time. The performance of event detection tools varies widely with no tool outperforming all others. DICAST allows researchers to employ a consensus approach to consider the most successful tools jointly for robust event detection. Furthermore, we propose the first reporting standard to unify existing formats and to guide future tool development.

Have extraction patterns in German adults with severe periodontitis changed between 2000 and 2010? Results from two cohort studies

AIM

The aim of this study was to evaluate whether extraction thresholds in persons with severe periodontitis have changed between 2000 and 2010 and whether potential shifts have contributed to the reported decrease in tooth extractions in German adults over the last decades.

MATERIALS AND METHODS

Data from two German population-based cohort studies in Northeast Germany (Studies of Health in Pomerania; SHIP-START [baseline 1997-2001; 11-year follow-up] and SHIP-TREND [baseline 2008-2012; 7-year follow-up]) were used. In SHIP-START (SHIP-TREND), 522 (478) participants with severe periodontitis according to the CDC/AAP case definition were included. Patterns of maximum probing depth (PD) and maximum clinical attachment level (CAL) for retained and extracted teeth were compared between SHIP-START and SHIP-TREND participants.

RESULTS

No major differences in patterns of baseline maximum CAL of retained or extracted teeth were detected between SHIP-START and SHIP-TREND. Extraction thresholds were identified at the baseline at maximum CAL ≥6 and ≥9 mm. Tooth-level incidence rates for extraction for baseline maximum CAL of 6 mm were comparable between SHIP-START and SHIP-TREND (17.1 vs. 15.9 events per 1000 person-years).

CONCLUSIONS

After a decade, teeth in persons with severe periodontitis were still undergoing extraction with minor or moderate attachment loss. A change in extraction pattern did not contribute to the higher tooth retention rate.