Dietary inflammatory potential is associated with poor periodontal health: A population-based study.

AIM: To investigate the association between dietary inflammatory potential and poor periodontal health. MATERIAL AND METHODS: A cross-sectional analysis of a nationally representative sample of participants was performed. NHANES 2011-2014 (n = 7081) and NHANES 2001-2004 (n = 5098) were used as discovery and validation datasets, respectively. The energy-adjusted dietary inflammatory index (E-DII) score was calculated for each participant based on 24-h dietary recalls to assess diet-associated inflammation. Periodontitis was defined by the CDC/AAP using clinical periodontal parameters. Natural cubic spline was applied to identify any non-linear associations of the E-DII score with moderate/severe periodontitis. Furthermore, interaction analyses were performed by age, gender, and race/ethnicity to explore the moderating roles of these factors. RESULTS: In the discovery dataset, a non-linear positive relationship with periodontitis was identified for the E-DII score (pnon-linearity  < .001) after adjustment for potential confounders. Compared with those individuals in the lowest tertile of E-DII, participants in the highest tertile who consumed a pro-inflammatory diet were 53% more likely to be periodontitis (OR tertile3vs1  = 1.53, 95% CI: 1.33-1.77). The validation dataset showed similar associations. Relatively stronger associations were seen in older adults and males. CONCLUSION: Consuming a pro-inflammatory diet indicated by the E-DII score is associated with periodontal disease in the U.S. general adult population.

Trends in socioeconomic inequality of periodontal health status among Dutch adults: a repeated cross-sectional analysis over two decades.

BACKGROUND: Studies exclusively focusing on trends in socioeconomic inequality of oral health status in industrialized countries are relatively sparse. This study aimed to assess possible differences in oral hygiene and periodontal status among people of different socioeconomic status (SES) in the Netherlands over two decades. METHODS: A repeated cross-sectional analysis of 3083 participants aged 25-54 years was conducted on the Dutch National Oral Health Surveys of 1995, 2002, 2007, and 2013. Plaque-free was defined according to the Simplified Oral Hygiene Index (OHI-S = 0). Periodontal status was classified in two different ways, either periodontal health/disease (probing pocket depth index [PDI] = 0/ ≥ 1) or with/without deep pockets (PDI = 2). We used the regression-based absolute and relative effect index to measure the absolute and relative socioeconomic inequalities. Multivariable logistic regressions were used to explore temporal trends in oral hygiene and periodontal status by low- and high-SES groups. RESULTS: Age-standardized percentages of individuals with plaque-free increased in the whole population from 1995 to 2013 (12.7% [95% CI 10.5-14.9] to 28.1% [24.8-31.5]). Plaque-free showed significant socioeconomic differences in absolute and relative inequalities in 2007 and 2013. Between 1995 and 2013, age-standardized percentage of periodontal health increased (from 51.4% [48.1-54.7] to 60.6% [57.0-64.1]). The significant absolute inequalities for periodontal health were seen in 2002 and 2013. The relative scale presented a similar pattern. Regarding deep pockets, there was little difference in the age-standardized overall prevalence in 1995 versus 2013 (from 6.5% [4.9-8.2] to 5.4% [3.7-7.0]). The significant absolute and relative inequalities in deep pockets prevalence were found in 1995. Yet, all interaction terms between survey year and SES did not reach significance (plaque-free: P = .198; periodontal health: P = .490; deep pockets: P = .678). CONCLUSIONS: Socioeconomic inequalities in oral hygiene and periodontal status were present in the Netherlands in the last two decades.

Histological responses of the periodontium to MTA: a systematic review.

AIM: The purpose of this systematic review was to investigate whether a mineral trioxide aggregate (MTA) restoration of an endodontic-periodontal communication leads to regeneration of the adjacent periodontal tissues. METHODOLOGY: The databases MEDLINE-PubMed, Cochrane-CENTRAL, and EMBASE were searched, up to July 2012. In vivo studies that reported on the histological response of the periodontium to MTA were selected. RESULTS: The screening of 98 title-abstracts, full-text reading, and hand searches in literature lists yielded 24 papers. All of them involved animals. There were no studies reporting on human histology. Study protocols presented heterogeneity regarding treated lesions, intervention, and reported outcomes. The histological results of the animal studies showed minimal inflammatory reactions, bone healing, periodontal ligament presence, and consistent cementum formation. Time lapse after mixing, bacterial contamination, root canal disinfection, and inflammation influenced MTA's cementoconductive properties. CONCLUSIONS: Within the limitations of the selected papers concerning inhomogeneous study protocols and low methodological quality scores, their findings were consistent with regard to MTA's biocompatibility and cementogenic ability. Experimental animal studies show that MTA can promote healing towards regeneration. There is now a distinct need to examine the clinical performance of MTA in well-controlled prospective human cohort studies.

White Blood Cell Count Mediates the Association Between Periodontal Inflammation and Cognitive Performance Measured by Digit Symbol Substitution Test Among Older U.S. Adults.

BACKGROUND: Systemic effects of periodontal infection may increase the risk of central neuroinflammation, aggravating impaired cognition. This study aims to examine whether systemic inflammatory factors mediate the possible association between periodontal inflammation and cognitive function. METHODS: We conducted a cross-sectional analysis of 766 participants aged ≥ 60 years and who had completed periodontal and cognitive examinations in the National Health and Nutrition Examination Survey (NHANES) 2001-2002. We used multivariable linear regression to investigate the overall association between periodontal health and cognitive function as measured by the digit symbol substitution test (DSST). Bleeding on probing (BOP) and periodontal inflamed surface area (PISA) were used to assess the periodontal inflammatory activity and burden, respectively. Mediation analyses were used to test the indirect effects of the BOP/PISA on DSST via C-reactive protein, white blood cell (WBC) count, and fibrinogen. RESULTS: Participants with superior periodontal health obtained higher DSST scores than those with poorer periodontal health, adjusting for demographic factors and chronic conditions. Concerning the inflammatory activity, WBC count acted as a full mediator in the association between BOP and DSST (ß = -0.091; 95% confidence interval [CI] = -0.174 to -0.008) and mediated 27.5% of the total association. Regarding the inflammatory burden, WBC count acted as a partial mediator in the association between PISA and DSST (ß = -0.059; 95% CI = -0.087 to -0.031) and mediated 20.3% of the total association. CONCLUSION: Our study indicated the potential role of systemic inflammatory factors as a mediator of associations between periodontal inflammation and cognitive function in the U.S. geriatric population.

Periodontal breakdown inter-tooth relationships in estimating periodontitis-related tooth loss.

OBJECTIVES: The reasons for tooth extraction are rarely recorded in epidemiological datasets. It poses a diagnostic challenge to determine if tooth loss is related to periodontal disease (TLPD). The present study aimed to assess the inter-tooth relationships based on the periodontal characteristics of existing teeth. METHODS: A cross-sectional dataset of 8,978 participants with complete periodontal examination (including probing pocket depth [PPD] and clinical attachment loss [CAL]) in the NHANES 2009-2014 was used in this study. Spearman rank correlation was applied to assess the inter-tooth correlations of PPD/CAL among 28 teeth after adjustment for relevant confounders. We further verify our findings in the Java Project on Periodontal Disease with TLPD information available (the number of TLPD = 12). RESULTS: Strong PPD/CAL correlations were observed in adjacent teeth (r for PPD = 0.652, r for CAL = 0.597; false discovery rate [FDR] <0.05) rather than those on non-adjacent teeth (r for PPD = 0.515, r for CAL = 0.476; FDR <0.05). The correlations increased among severe periodontitis cases (CAL ≥5 mm or PPD ≥6 mm). In line with this, we further observed that the teeth adjacent to the TLPD tooth had the most alveolar bone loss in the Java dataset. CONCLUSION: The periodontitis parameters (PPD/CAL) of adjacent teeth could be a potential indicator to estimate TLPD when actual reasons for tooth extraction are unknown. CLINICAL SIGNIFICANCE: Periodontally compromised teeth adjacent to a lost tooth may help estimate whether the loss could be related to periodontal disease when the actual extraction reasons are unknown.

Relationship between 18F-FDG Uptake in the Oral Cavity, Recent Dental Treatments, and Oral Inflammation or Infection: A Retrospective Study of Patients with Suspected Endocarditis.

[18F]-fluorodeoxyglucose positron emission tomography ([18F]FDG PET/CT) has proven to be a useful diagnostic tool in patients with suspected infective endocarditis (IE), but is conflicting in relation to dental procedures. QUESTIONS: Is there a correlation between [18F]FDG PET/CT findings, recent dental treatment, and an affected oral cavity? (2) Is there a correlation between infective endocarditis (IE), oral health status, and (extra)cardiac findings on [18F]FDG PET/CT? METHODS: This retrospective study included 52 patients. All [18F]FDG PET/CT scans were examined visually by pattern recognition using a three-point scale and semi-quantified within the volume of interest (VOI) using SUVmax. RESULTS: 19 patients were diagnosed with IE (group 1), 14 with possible IE (group 2), and 19 without IE based on the modified Duke criteria (group 3). No correlation was found between visual PET and SUVmax and sites of oral inflammation and infection. The visual PET scores and SUVmax were not significantly different between all groups. A significant difference in the SUVmax of the valve between all groups was observed. CONCLUSIONS: This study suggests that no correlation exists between the PET findings in the oral cavity and dental treatments or inflammation/infection. No correlation between IE, actual oral health status, and extra-cardiac findings was demonstrated. Additional research is needed to conclude whether [18F]FDG PET/CT imaging is a reliable diagnostic modality for oral inflammation and infection sites.

Effect of Dentin Matrix Components on the Mineralization of Human Mesenchymal Stromal Cells.

IMPACT STATEMENT: This research has been conducted with the aim to contribute to the development of treatment modalities for the reconstruction of lost/damaged mineralized tissues. Currently, determining the most appropriate stromal cell population and signaling cues stands at the core of developing effective treatments. We provide new insights into the effect of innate inductive cues found in human dentin matrix components, on the osteogenic differentiation of various human stromal cell types. The effects of dentin extracellular matrix components on umbilical cord mesenchymal stromal cells have not been investigated before. The findings of this study could underpin translational research based on the development of techniques for mineralized tissue engineering and will be of great interest for the readership of Tissue Engineering Part A.

Secreted products of oral bacteria and biofilms impede mineralization of apical papilla stem cells in TLR-, species-, and culture-dependent fashion.

Regenerative endodontics exploits the mineralization potential of stem cells from the apical papilla (SCAPs) in order to promote root maturation of permanent immature teeth. SCAPs may encounter post-disinfection residual bacteria either in planktonic or in biofilm growth mode. Bacterial components bind to Toll-like receptors (TLRs) and trigger pro-inflammatory responses. We hypothesized that biofilm-triggered TLR activation affects the mineralization potential of human SCAPs. SCAPs were challenged with conditioned media derived from standardized dual-species biofilms and planktonic bacterial cultures and their inflammatory status and mineralization capacity were studied. Bacterial products from both growth modes (planktonic vs. biofilm) compromised cell viability, proliferation and mineralization capacity of SCAPs, but in a species- and growth mode-dependent fashion. While TLR4 expression remained unaffected, TLR2 expression was upregulated coinciding with a pro-inflammatory activation of SCAPs. Moreover, TLR and its downstream TGF-ß-associated kinase (TAK1) appeared to be blocking mineralization, as inhibition of these factors restored it. In conclusion, bacterial products promoted the pro-inflammatory status and inhibited mineralization of human SCAPs in a TLR-, species-, and culture-dependent fashion. TLR2 emerged as the pivotal mediator of these responses and further research is warranted towards the judicious manipulation of SCAPs in order to modify the untoward events of TLR-priming and signaling.

Detection of Legionella Anisa in Water from Hospital Dental Chair Units and Molecular Characterization by Whole-Genome Sequencing.

This study aims to assess contamination with Legionella spp. in water from dental chair units (DCUs) of a hospital dental ward and to perform its molecular characterization by whole-genome sequencing (WGS). We collect eight water samples (250 mL) from four DCUs (sink and water-syringe). Samples are tested for the presence of Legionella spp. (CFUs/mL) by culturing according to the Nederland Norm (NEN) 6265. Three DCUs are found positive for Legionella anisa, and four isolates are cultured (sink n = 2, water-syringe n = 1; two isolates from the same chair) with 1 × 10² CFU/mL. Whole-genome multi-locus sequence typing (wgMLST) results indicate that all strains belong to the same cluster with two to four allele differences. Classical culture combined with WGS allows the identification of a unique clone of L. anisa in several DCUs in the same hospital dental ward. This may indicate a common contamination source in the dental unit waterlines, which was fixed by replacing the chairs and main pipeline of the unit. Our results reveal tap water contamination in direct contact with patients and the usefulness of WGS to investigate bacterial molecular epidemiology.

The risk of furcal perforation in mandibular molars using Gates-Glidden drills with anticurvature pressure.

OBJECTIVE: The aim of this study was to determine whether using Gates-Glidden (GG) drills and anticurvature pressure in curved mesial root canals of mandibular molars could remove more dentin from the mesial canal wall and remove less dentin from the distal canal wall at a level 2 mm below the furcation. STUDY DESIGN: In 5 groups of mesial roots with an average curvature of 32-34 degrees, 103 canals were prepared using a size #2 or #3 GG drill in the coronal third (straight portion of the canal only) or coronal half (straight portion and part of the curved portion), with or without applying anticurvature pressure. Using a modification of the Bramante muffle mold the cross-section of the mesial root at 2 mm below bifurcation was photographed twice, before and after the use of GG; the photos were then scanned as tagged image files. The thickness of the mesial and distal canal walls wer measured using an image analysis program. The reduction of the wall thickness after the use of GG was calculated. RESULTS: Before enlargement, the average and minimal thickness of the distal wall was 0.92 and 0.43 mm respectively, thinner than that of the mesial wall (1.50 and 0.87 mm, correspondingly). After the use of GG, the reduction of the mesial wall was similar to the reduction of the distal wall (P > .05 for all groups). In 4 groups the maximal reduction of the distal wall was > or =0.72 mm. CONCLUSIONS: After using GG drills and anticurvature pressure, dentin was uniformly removed regardless of the size of the GG and the depth of placement of GG. Flaring with GG drills in mandibular molars may result in perforations; application of anticurvature pressure did not reduce the risk.

Fluid transport along gutta-percha backfills with and without sealer.

OBJECTIVE: The use of heat may influence the sealing ability of sealer. The aim of this study was to compare the fluid transport along the gutta-percha backfill portion when different sealers were used or no sealer at all. STUDY DESIGN: Four groups consisting of the roots of maxillary and mandibular canines were instrumented and obturated with vertically compacted warm gutta-percha. Down-pack was carried out using Touch 'n Heat (Analytic Technology, Redmond, Wash, USA) and prefitted pluggers. Back filling was achieved by injecting warm gutta-percha using Obtura II (Obtura Corporation, Fenton, Mo). In the first 3 groups, 1 of 3 sealers was used: RoekoSeal Automix (RSA), Pulp Canal Sealer EWT (EWT), and AH26. In the fourth group no sealer was used. The apical root filling was removed, and fluid transport along the backfill portion was measured using a fluid transport device. RESULTS: A statistically significant difference in fluid transport was found among the 4 groups (P = .038). The no-sealer group recorded the highest fluid transport. The AH26 group was the only sealer group that displayed significantly less fluid transport than the no-sealer group (P = .006). The AH26 displayed less fluid transport than the EWT group (P = .017). CONCLUSION: The backfills with AH26 as sealer provided a better seal than the backfills of injected warm gutta-percha with EWT as sealer or with no sealer at all.

The effect of using an inverted master cone in a lateral compaction technique on the density of the gutta-percha fill.

OBJECTIVE: We sought to measure and calculate the percentage of the gutta-percha-filled area in the apical root canal after the use of a standardized or inverted master cone in cold lateral compaction.Study design Two groups of extracted mandibular premolars with a single canal were instrumented with instruments of the same size; furthermore, they were obturated with laterally compacted gutta-percha cones with AH26 used as a sealer. In the first group, a standardized master cone was used with its narrow end in an apical position, whereas in the other group, an inverted master cone was used with its wide end in an apical position. The 2 master cones had the same apical diameter and fit in the apical canal. After lateral compaction, horizontal sections were cut at a level 3 and 5 mm from the apex of each filled tooth. Photographs of the sections were taken by using a microscope equipped with a digital camera; the photos were then scanned as tagged-image file format images. The cross-sectional area of the canal and the gutta-percha were measured by using an image-analysis program. The percentage of gutta-percha-filled area was calculated. RESULTS: At both levels, the inverted master cone produced a significantly higher percentage, statistically, of gutta-percha-filled area than did the standardized master cone (P =.001 at 3 mm; P =.012 at 5 mm). CONCLUSION: The use of an inverted master cone in cold lateral compaction may facilitate the apical placement of accessory cones, significantly increasing the volume of gutta-percha while reducing the volume of sealer in the apical root canal.

Oscillation characteristics of endodontic files: numerical model and its validation.

During a root canal treatment, an antimicrobial fluid is injected into the root canal to eradicate all bacteria from the root canal system. Agitation of the fluid using an ultrasonically vibrating miniature file results in a significant improvement in the cleaning efficacy over conventional syringe irrigation. Numerical analysis of the oscillation characteristics of the file, modeled as a tapered, driven rod, shows a sinusoidal wave pattern with an increase in amplitude and decrease in wavelength toward the free end of the file. Measurements of the file oscillation with a scanning laser vibrometer show good agreement with the numerical simulation. The numerical model of endodontic file oscillation has the potential for predicting the oscillation pattern and fracture likeliness of various file types and the acoustic streaming they induce during passive ultrasonic irrigation.

Localized removal of layers of metal, polymer, or biomaterial by ultrasound cavitation bubbles.

We present an ultrasonic device with the ability to locally remove deposited layers from a glass slide in a controlled and rapid manner. The cleaning takes place as the result of cavitating bubbles near the deposited layers and not due to acoustic streaming. The bubbles are ejected from air-filled cavities micromachined in a silicon surface, which, when vibrated ultrasonically at a frequency of 200 kHz, generate a stream of bubbles that travel to the layer deposited on an opposing glass slide. Depending on the pressure amplitude, the bubble clouds ejected from the micropits attain different shapes as a result of complex bubble interaction forces, leading to distinct shapes of the cleaned areas. We have determined the removal rates for several inorganic and organic materials and obtained an improved efficiency in cleaning when compared to conventional cleaning equipment. We also provide values of the force the bubbles are able to exert on an atomic force microscope tip.

A 1-year follow-up study on leakage of single-cone fillings with RoekoRSA sealer.

OBJECTIVE: The aim of this study was to measure long-term leakage along single cone (SC) fillings. STUDY DESIGN: Two groups of canines (n = 30) were prepared and a size 55 file was the apical master file. Step-back was performed using files of sizes 60, 70, and 80. The canals were filled by the single cone technique using RoekoRSA as sealer. To place sealer into each canal, a bidirectional spiral was used in 1 group, whereas a gutta-percha cone was used in the other group. Immediately after root filling, the coronal portion of root filling was removed by postspace preparation. Leakage along the 4 mm remaining apical root filling was measured after 1 week and again after 1 year using a fluid transport model. Ten additional canine roots were prepared and filled with gutta-percha cones without sealer, serving as positive controls. Occurrence of apical extrusion of materials was recorded. RESULTS: The apical root filling in all 60 canine roots did not show leakage either at 1 week or at 1 year. All 10 positive controls showed gross leakage (>20 muL/h). In no case gutta-percha extruded through the apical foramen. Sealer extruded apically in 88% of the roots where a gutta-percha cone was used to introduce sealer, whereas in 28% of the roots where a bidirectional spiral was used to introduce sealer (by chi-square test, P < .05). CONCLUSION: In wide and straight canals, SC fillings with RoekoRSA sealer prevented fluid transport for 1 year. Using bidirectional spiral to place sealer reduced sealer extrusion under the conditions of this experiment.