Inflammatory Response to Wear Particles: Comparisons Between Zirconia and Titanium In Vitro.

PURPOSE: To compare the inflammatory responses of peripheral blood mononuclear cells (PBMCs) subjected to titanium (Ti) and/or zirconia (Zr) particles while growing on Ti or Zr discs. MATERIALS AND METHODS: In total, 240 discs were fabricated at a size of 2 mm in height and 5 mm in diameter. Of the 240 discs, 120 discs were made of Ti (commercially pure [CP] grade 4), and 120 discs were made of Zr (3 mol% yttria-stabilized zirconia polycrystals [3Y-TZP]). The PBMCs were cultured on the two-disc materials, and particles with a size up to 20 mm Ti (99.5% Ti) and 0.1 to 0.2 mm Zr (3Y-TZP) were added to the cultures. The concentration levels of inflammatory cytokines in culture supernatants were measured through Bio-Plex assay (Bio-Rad Laboratories), and light microscopic analysis was performed to detect cell attachment and characterize particle shape and cell-particle interaction. RESULTS: The inflammatory responses of PBMCs were generally higher when cells were cultured on a Ti surface compared to a Zr surface. In addition, higher cytokine levels were seen when cells were cultured in the presence of Ti particles compared to Zr particles when no discs were used. However, there were only significantly increased levels for three cytokines (MCP-1, IFN-γ, and TNF-α) when particles were added to Ti discs. Higher release of neutrophil extracellular traps (NETs) from neutrophils were seen in presence of Zr particles compared to Ti particles. A reduction in cell death was observed in the presence of Zr particles compared to Ti particles and unstimulated control samples. CONCLUSIONS: The type of growth material and presence of particle affects PBMCs in vitro. Cells seeded on Ti discs and together with Ti particles generated higher levels of inflammatory cytokines compared to the Zr counterparts.

Adolescents' self-reported experiences following a person-centred, theory-based educational intervention versus conventional education for improved oral hygiene: Analysis of secondary outcomes of a randomized field study.

AIM: To analyse adolescents' self-reported experiences and behavioural outcomes of a person-centred, theory-based intervention in comparison with conventional information/instruction for improved oral hygiene. MATERIALS AND METHODS: Data were derived from a prospective, multi-centred, two-arm, quasi-randomized field study focusing on the effectiveness of educational interventions for improved oral hygiene. Dental hygienists working within the Public Dental Service, Västra Götaland, Sweden, provided treatments, and adolescents with poor oral hygiene conditions were eligible for participation. The person-centred test intervention was based on social cognitive constructs, and motivational interviewing was used as an approach in communication. The control intervention included conventional information/instructions. Clinical examinations were performed, and questionnaires were distributed at baseline and at 6 months. Three-hundred and twelve patients were enrolled, and data from 276 patients, following treatment per protocol, were analysed. RESULTS: The test group was more satisfied with the education about gingivitis (very good: 61% vs. 37%) and communication during therapy (very good: 69% vs. 50%) and reported to a larger extent that they were much more careful regarding their oral hygiene after the treatment (30% vs. 15%) and had higher confidence about keeping up healthy gingival conditions, in comparison with the control group (all p < .01). CONCLUSIONS: The person-centred, theory-based intervention was superior in terms of adolescents' experiences of education and communication during therapy and self-reported oral hygiene behavioural outcomes at 6 months, in comparison with conventional information/instruction.

Impact of Medical and Surgical Obesity Treatment on Dental Caries: A 2-Year Prospective Cohort Study.

The objective was to study the long-term effects on oral health of bariatric surgery compared with medical treatment of obesity. Swedish females with morbid obesity (n = 66; 18-35 years at baseline) were followed prospectively from before obesity treatment until 2 years after treatment. The main response variable was dental caries registered according to the ICDAS-II system. Possible confounding factors, such as sociodemographic characteristics, general health, oral health habits, and oral hygiene, were controlled for. The statistical methods included χ2 tests, Student's t tests, one-way ANOVA, Wilcoxon's nonparametric tests, and linear regression models. In the surgically treated patients (n = 40), a significant increase over time in enamel caries (mean increase 4.13 tooth surfaces ICDAS1-2), dentine caries (mean increase 2.18 tooth surfaces ICDAS3-6), and total caries (mean increase 6.30 tooth surfaces ICDAS1-6) was registered (all p < 0.001), which was not seen in the medically treated patients (n = 26). However, the difference between the treatment groups (surgical or medical) was only statistically significant for enamel caries (crude ß 4.89, p = 0.003) and total caries (crude ß 6.53, p < 0.001). The relationships were stable and independent of differences in confounders as socioeconomy, general health, and oral health behaviors. In conclusion, 2 years after obesity treatment, a significant increase in dental caries was registered in the surgically treated but not in the medically treated women. The dental service should intensify its preventive efforts in individuals undergoing obesity treatment.

Hypertension treatment in the oldest-old: focus group interviews with Swedish general practitioners.

OBJECTIVE: This study explored the considerations and experiences of Swedish General Practitioners (GPs) of hypertension treatment in patients 80 years and above. DESIGN: Qualitative design with focus group interviews. Data were analysed by qualitative content analysis. SETTING: Primary health care centres (PHCCs), both rural and urban, in the Region of Västra Götaland, Sweden. SUBJECTS: GPs and GP trainees working at PHCCs in 2019 and 2020. Five focus group interviews with 24 physicians were performed. MAIN OUTCOME MEASURES: Considerations and experiences of hypertension treatment in the oldest-old. RESULTS: Eighteen GPs and six GP trainees participated in the study. The latent content was formulated in a theme: 'The physician's decision-making in the treatment of hypertension in the oldest-old implies the inclusion of both medical and humanistic considerations.' The manifest content constituted three main categories: 'The patient characteristics' included medical condition, behavioural factors and daily life. 'The physician's role' described the GP as a professional and her/his experienced support. 'The treatment decision' considered these categories and involved risk-benefit balancing and communication. For the future, the participants proposed better guidelines for the oldest-old multimorbid patients, increased teamwork, continuous cooperation with nurses and better cooperation with hospital physicians. CONCLUSION: Hypertension care for the oldest-old was experienced as complicated by GPs, due to the need of balancing medical and humanistic considerations. The GP's clinical experience and the received support were of importance when making the treatment decision based on risk-benefit balancing and communication with the patient.Key pointsGPs experienced the task of caring for the oldest-old patients with hypertension as complicated.Patient factors like multimorbidity, polypharmacy, behavioural factors and the patient's condition of daily life were identified.Clinical experience and the experienced support at the PHCC were discussed as important for the GPs' treatment decision.Treatment decisions for the oldest-old patients with hypertension were based on risk-benefit balancing and communication with the patients.

Adolescents' experiences of a theory-based behavioural intervention for improved oral hygiene: A qualitative interview study.

OBJECTIVES: Adequate oral hygiene, that is self-performed infection control, is crucial to prevent periodontal disease. Epidemiological studies reveal poor oral hygiene conditions among Swedish adolescents and indicate a need for more effective prevention programs. The aim of the current study was to analyse adolescents' experiences of a person-centred, theory-based, oral health education program for improved oral hygiene. METHODS: Data were obtained by interviewing 19 adolescents treated by dental hygienists in accord with the person-centred education program in a preceding clinical field study (ClinicalTrials.gov NCT02906098). Study participants were selected to reflect a variation of male and female adolescents, treated at clinics in areas with various socio-demographic profiles within Region Västra Götaland, Sweden. Interviews were audio-taped, transcribed verbatim and analysed with qualitative content analysis. RESULTS: A main theme was identified: 'Adolescents on a guided and challenging journey towards beneficial oral hygiene behavior'. The results elucidate the importance of a person-centred approach in therapy. The adolescents described insight on a personal level about the importance of improved oral hygiene as fundamental for behavioural change. Planning and monitoring of the behaviour, with guidance and support by the dental hygienist, was considered to facilitate change and encouraged further behavioural efforts. However, the adolescents expressed a need of reminders and support to keep up oral hygiene routines over time. CONCLUSIONS: The study brings knowledge on factors of importance in educational interventions to increase beneficial health behaviours among adolescents and emphasize areas for further improvements of such interventions.

The effect of a non-tobacco-based nicotine pouch on mucosal lesions caused by Swedish smokeless tobacco (snus).

Oral mucosal lesions are commonly found in Swedish smokeless tobacco (snus) users where the pouch is placed. These lesions are reversible, that is, clinical and histological tissue changes return to normal following cessation. However, the exact mechanisms behind these changes are unknown. The main aim of this study was to investigate how snus-like non-tobacco-based nicotine pouches affect the oral mucosa and the severity of pre-existing lesions. Sixty regular users of Swedish smokeless tobacco were encouraged to substitute their snus with non-tobacco-based nicotine pouch products during a 6-week period. Meanwhile, oral mucosal lesions were assessed using a four-degree scale. Over time, a reduction of pre-existing mucosal lesions was observed between baseline and the final visit. In a second part, the effect of exposure to regular snus on the production of 48 different cytokines in peripheral blood mononuclear cells was compared in vitro with that resulting from exposure to the non-tobacco-based nicotine products. Results showed significantly increased production of proinflammatory cytokines in cells exposed to regular snus compared to untreated or cells exposed to the non-tobacco-based nicotine products. This may be related to the improved clinical appearance of the oral mucosa in the participants that used the non-tobacco-based nicotine test pouches.

Oral health by obesity classification in young obese women - a cross-sectional study.

OBJECTIVE: To explore oral health by increasing degree of obesity and the influence of modifying factors. MATERIALS AND METHODS: A cross-sectional design was used. Swedish females (n = 118; 18-35 years) with morbid obesity were recruited from the BAriatric SUbstitution and Nutrition study (BASUN). Body mass index (BMI) was used as continuous and categorized into 35-39.9 kg/m2/40-44.9 kg/m2/≥45 kg/m2. Oral examinations assessed dental caries using the ICDAS system, periodontal status and saliva characteristics. Information on sociodemographics, oral health behaviour and symptoms was collected via a questionnaire. RESULTS: Mean BMI was 42.2 kg/m3 (SD 4.0; range 35.0-63.7). Significantly higher frequencies of dentine caries (p = .001) and total caries (p = .046) were found with higher BMI with an increase in total caries by 0.59 tooth surface (p = .025) for each increasing BMI degree. There were consistent associations between obesity and dentine caries for the group with the highest BMI (≥45), adjusted RR 2.08 (95% CI 1.20-3.61), and all stages of caries, adjusted RR 1.41 (95% CI 1.02-1.96). High scores were found for dental plaque (50.2%) and gingivitis (34.5%). CONCLUSION: Young obese women exhibited poor oral health with higher caries levels by higher BMI. Dental care should adapt the prevention efforts for obese individuals. Trial Registration: The trial was prospectively registered on March 03; 2015; NCT03152617.

Glycans as Potential Diagnostic Markers of Traumatic Brain Injury.

The diagnosis of mild traumatic brain injury (TBI) is challenging in the acute setting because the symptoms are nonspecific and often transient, or they develop with a delay. In these cases, the criteria for acute head imaging are frequently not fulfilled. This may lead to missed diagnoses in emergency care. There is a need for developing a rapid diagnostic test to verify the presence of TBI using body fluids. Blood, urine, and saliva samples from 11 adult patients (mean age 64 years, SD 24 years) with acute and clinically diagnosed TBI, and 12 healthy volunteers were collected at Turku University Hospital during a period of 5 months. The injuries necessitated hospitalization for at least one day. The TBIs were classified mild in nine cases and severe in two cases. The mean period between the trauma and the time for obtaining the samples was 27 h, SD 11 h. The samples were analyzed in an ISO-certified laboratory for the number of lectin-bound glycan molecules indicating destruction of nerve tissue. The screening was performed on several possible glycans for binding, and the measurement by degree of fluorescence. In the analysis, the group of patients with TBI was compared with healthy volunteers. The results showed a significant decrease (p < 0.05, Wilcoxon rank-sum two-sided test) in the level of two glycans in plasma, but no significant increase for any glycan; in saliva, one glycan showed a significant increase in the TBI group; in urine, three glycans were significantly different between the groups (one showed an increase, whereas two showed a decrease). The results support the idea of conducting more research on how diagnostic glycans could be detected in body fluids after TBI. As a proof-of-concept, significant changes in the concentration of five glycans were found in plasma, saliva, and urine between TBI patients and healthy controls. This may enable the development of a rapid body fluid-based point-of-care test to identify patients with TBI after a head injury.

Oral health profile of postbariatric surgery individuals: A case series.

OBJECTIVES: To describe the oral health profile of individuals who had undergone gastric bypass surgery (GBP) or sleeve gastrectomy (SG) to generate hypotheses for further studies. MATERIAL AND METHODS: Fourteen individuals treated with GBP or SG surgery ≥ 2 years ago and with observed and/or perceived oral problems were recruited to a case series. The documentation included clinical and radiographic examinations, biomedical sampling, and self-reported diet and questionnaires. The results are presented descriptively. RESULTS: The age range was 31 to 66 years and all had a BMI > 25 (range 25.4-44.7). Only four participants were fully dentate. Eleven out of 14 individuals exhibited severe decay. A majority had poor oral hygiene and high bacterial counts. The flow rates of unstimulated saliva were extremely low and hyposalivation was present in ten of the fourteen cases. Most perceived several oral health problems, such as chewing difficulty and tooth hypersensitivity. CONCLUSIONS: Individuals who had undergone GBP or SG surgery had poor clinically diagnosed oral health and perceived oral health problems. Longitudinal studies are needed to monitor the patients' oral health, from before bariatric surgery to long-term postoperatively.

Immunological response of human leucocytes after exposure to lipopolysaccharides from Porphyromonas gingivalis.

Porphyromonas gingivalis (P. gingivalis) is a gram-negative bacterium and an important etiologic agent of periodontitis. P. gingivalis releases outer membrane vesicles containing lipopolysaccharides (LPS), which can penetrate periodontal tissues. Once in the periodontal tissues and in contact with immune cells, it may participate in the destructive innate host response associated with the disease. The exact mechanism of P. gingivalis LPS in the disease process is not clear, but it is known to affect a variety of immune responses. OBJECTIVES: To investigate how LPS from P. gingivalis affect neutrophil extracellular trap (NET) formation, cell death and production of cytokines from human neutrophils and peripheral mononuclear blood mononuclear cells (PBMCs). MATERIALS AND METHODS: Isolated neutrophils and PBMCs were cultured with LPS from P. gingivalis or Escherichia coli (E. coli) (control). The NET formation was measured using Sytox green stain. Cell death of neutrophils and PBMCs was analyzed using flow cytometry or Sytox green stain. Cytokine production was measured using enzyme-linked immunosorbent assay (ELISA) kit or Bio-Plex assay. RESULTS: Exposure to LPS from P. gingivalis and E. coli caused significantly lower cell death in neutrophils. NETs were formed after exposure to the two different LPS. In PBMCs, exposure to P. gingivalis and E. coli LPS caused increased levels of IL-1ß and IL-6 compared to unstimulated controls. Increased cell death in PBMCs after exposure to LPS from E. coli in comparison to LPS from P. gingivalis and unstimulated controls was also observed. CONCLUSIONS: LPS from P. gingivalis has the ability to affect both human neutrophils and PBMCs with regard to cytokine production, cell death and production of NETs. LPS from P. gingivalis could be involved in the pathogenesis of periodontitis, and our results may contribute information regarding possible markers for diagnosis and targets for treatment of periodontal disease.

Inflammatory Response to Cobalt-Chromium Alloys Fabricated With Different Techniques.

OBJECTIVES: To explore the in vitro cytokine expression of human peripheral blood mononuclear cells exposed to cobalt-chromium alloys, manufactured with different techniques, in comparison with commercially pure titanium grade 4 and titanium alloy grade 23. MATERIAL AND METHODS: Peripheral blood mononuclear cells (PBMC) were collected from 10 healthy blood donors and exposed to machine-ground coin-shaped: (a) cobalt-chromium (Co-Cr) specimens (n = 5) manufactured by four techniques, i.e. cast, milled, laser melted and presintered milled; (b) commercially pure titanium grade 4; and (c) titanium alloy grade 23. The cells were cultured for 4, 24 and 72 hours followed by investigations of pro- and anti-inflammatory cytokine release using Bio-Plex Pro™. RESULTS: In general, the PBMC produced significantly more cytokines when exposed to the cast and presintered milled Co-Cr materials compared to laser melted, milled Co-Cr and titanium materials. CONCLUSIONS: Within the limitation of the present study, it may be suggested that cast and presintered milled cobalt-chromium alloys provoke a stronger inflammatory response compared to milled and laser melted cobalt-chromium alloys and titanium materials.

Oral Lactobacillus strains reduce cytotoxicity and cytokine release from peripheral blood mononuclear cells exposed to Aggregatibacter actinomycetemcomitans subtypes in vitro.

BACKGROUND: This study evaluated the effect of oral lactobacilli on the cytotoxicity and cytokine release from peripheral blood mononuclear cells (PBMCs) when exposed to Aggregatibacter actinomycetemcomitans subtypes in vitro. The supernatants and cell wall extracts (CWEs) of eight A. actinomycetemcomitans strains, representing different subtypes, and three Lactobacillus strains were used. The PBMCs from six blood donors were exposed to supernatants and CWEs of A. actinomycetemcomitans or Lactobacillus strains alone or combinations and untreated cells as control. The cytotoxicity was determined by trypan blue exclusion method and IL-1ß secretion by ELISA. TNF-α, IL-6, and IL-8 secretions were measured using Bioplex Multiplex Immunoassay. RESULTS: Supernatants or CWEs from all bacterial strains showed cytotoxicity and IL-1ß secretion and the subtypes of A. actinomycetemcomitans showed generally a significantly higher effect on PBMCs than that of the Lactobacillus strains. Two highly toxic A. actinomycetemcomitans strains (JP2 and JP2-like) induced a higher response than all other strains. When combined, Lactobacillus significantly reduced the toxicity and the IL-1ß secretion induced by A. acinomycetemcomitans. The effect varied between the subtypes and the reduction was highest for the JP2 and JP2-like strains. The Lactobacillus paracasei strain SD1 had a higher reducing effect than the other Lactobacillus strains. This strain had a consistent reducing effect on all subtypes of A. actinomycetemcomitans cytotoxicity, and release of IL-1ß, IL-6, IL-8, and TNF-α from PBMCs of the blood donors. A strong and significant variation in cytokine release between the six blood donors was noticed. CONCLUSIONS: Lactobacillus spp. and L. paracasei SD1 in particular, showed a limited but statistically significant reducing interaction with A. actinomycetemcomitans toxicity and release of cytokines in vitro.

Volume Change in Frontal Cholinergic Structures After Traumatic Brain Injury and Cognitive Outcome.

The cholinergic nuclei in the basal forebrain innervate frontal cortical structures regulating attention. Our aim was to investigate if cognitive test results measuring attention relate to the longitudinal volume change of cholinergically innervated structures following traumatic brain injury (TBI). During the prospective, observational TBIcare project patients with all severities of TBI (n = 114) and controls with acute orthopedic injuries (n = 17) were recruited. Head MRI was obtained in both acute (mean 2 weeks post-injury) and late (mean 8 months) time points. T1-weighted 3D MR images were analyzed with an automatic segmentation method to evaluate longitudinal, structural brain volume change. The cognitive outcome was assessed with the Cambridge Neuropsychological Test Automated Battery (CANTAB). Analyses included 16 frontal cortical structures, of which four showed a significant correlation between post-traumatic volume change and the CANTAB test results. The strongest correlation was found between the volume loss of the supplementary motor cortex and motor screening task results (R-sq 0.16, p < 0.0001), where poorer test results correlated with greater atrophy. Of the measured sum structures, greater cortical gray matter atrophy rate showed a significant correlation with the poorer CANTAB test results. TBI caused volume loss of frontal cortical structures that are heavily innervated by cholinergic neurons is associated with neuropsychological test results measuring attention.

Primary care physicians' concerned voices on sickness certification after a period of reorganization. Focus group interviews in Sweden.

Objective: This study explored the views of primary health care (PHC) physicians on sickness certification after reforms in 2005 prompted by the Swedish government to increase the quality and decrease the inequalities, and costs of sickness certification.Design: Qualitative design with focus group interviews. Data were analysed using qualitative content analysis.Setting: Urban and rural PHC centres in Region Västra Götaland, Sweden.Subjects: GPs, interns, GP trainees and locums working in PHC centres 2015. Six focus group interviews with 28 physicians were performed.Main outcome measures: Experiences and reflections about the sickness certification system.Results: The latent content was formulated in a theme: 'The physicians perceived the sickness certification process as emotive and a challenge to master with differing demands and expectations from authorities, management and patients'. Sickness certification could be easy in clear-cut situations or difficult when other factors besides the pure medical were ruling the decisions. The physicians' coping strategies for the task included both active measures (cooperation with health care staff and social insurance officers) and passive adaptation (giving in or not caring too much) to the circumstances. Proposals for the future were to transfer lengthy sickness certifications and rehabilitation to specialized teams and increase cooperation with rehabilitation coordinators and social insurance officers.Conclusions: Political decisions on laws and regulations for sickness certification impacted the primary health care making the physicians' work difficult and burdensome. Their views and suggestions should be carefully considered in future organization of primary care. KEY POINTSIn 2005 Swedish government introduced reforms to decrease the inequalities and costs of sickness certification and facilitate the physicians' work. Focus group interviews with Swedish primary care physicians revealed that sickness certification was challenging due to differing demands from authorities, management and patients.Coping strategies for the sick-listing task included both active measures and passive adaptation to the circumstances.A proposal for future better working conditions for physicians was to transfer lengthy sickness certifications and rehabilitation to specialized teams.

A longitudinal study of the impact of change in socioeconomic status on dental caries in the permanent dentition of Swedish children and adolescents.

OBJECTIVES: The overall aim was to analyse longitudinally the development of dental caries in the permanent dentition of children and adolescents in a Swedish region, in relation to possible change in socioeconomic status (SES). METHODS: A total of 259 448 individuals in western Sweden were followed over a 3-year period, through dental journal records at baseline (3-19-year-olds) and 1-3 dental check-ups during the follow-up period. Official socioeconomic register information (ethnicity, wealth, parental education and employment) was available at both baseline and follow-up. Data were used both as independent single variables and combined in an index. Gender, age and caries status at baseline and the examination years were included as covariates in the regression models. RESULTS: Associations over time were found between SES and dental caries in young people. A persistently low SES was associated with the greatest risk of both new and accumulated (decayed plus filled teeth/approximal surfaces) caries; however, any change in SES, whether improved or worsened, led to a greater risk. An increased risk of new caries events was identified for those who were older at baseline and by examination year. On average, the increase per year in decayed and/or filled teeth and in approximal surfaces was 0.23 and 0.12, respectively. CONCLUSION: SES was shown to be an important risk factor for dental caries over time in young Swedish people. Prevention programmes should pay particular attention to the needs of socioeconomically vulnerable individuals and groups.

Oral Health-Related Quality of Life After Gastric Bypass Surgery.

OBJECTIVE: The aim was to examine how individuals treated for obesity with gastric bypass (GBP) surgery perceived their oral health and oral health-related quality of life (OHRQoL). METHOD: All individuals in one Swedish region who had undergone GBP surgery (n = 1182) were sent a postal questionnaire 2 years after surgery. The questionnaire comprised items on sociodemographics, oral symptoms and the Oral Health Impact Profile-49 to assess the OHRQoL. RESULTS: The mean age was 47.6 years with 75% females, response rate 55.3%. The self-perceived oral health was rated low by 45% of the respondents. Gender differences were seen, for instance, regarding hypersensitive teeth (men 18.8%, women 30.8%, p = 0.003). Nine out of ten reported at least one oral impact experienced sometimes, fairly or very often, according to the Oral Health Impact Profile-49 (OHIP-49). The mean additive OHIP-49 score was 30.3 (SD 36.1). The associations between self-reported oral health and OHRQoL were consistent throughout. Tooth hypersensitivity generated an OR of 2.28 (95% CI 2.28-8.46) of having ≥ 2 impacts on OHRQoL. CONCLUSION: A large proportion of individuals having undergone GBP surgery reported problems with their oral health and impacts on their OHRQoL, indicating a need for medical and dental staff-surgeons and general practitioners as well as other health professionals-to offer oral health promotion and prevention measures.

Multilevel Analysis of Dental Caries in Swedish Children and Adolescents in Relation to Socioeconomic Status.

The objective was to investigate the variability in dental caries experience in Swedish children and adolescents, at two different area levels: dental clinics and SAMS (small areas for market statistics), with respect to multiple individual socioeconomic factors (SES). Records of manifest caries using the DMFT indices (decayed, missing, filled teeth, dependent variables) were collected from electronic dental records for 300,988 individuals aged 3-19 years (97.3% coverage) from the Region Västra Götaland, Sweden. SES data were obtained from official registers and covered ethnicity, wealth, parental education, and employment. The SES variables were used as an independent aggregated variable - an in dex - categorized in deciles. Age and gender were independently included in the multilevel models. Two-level logistic regression analyses explored the probability of a dental caries experience and the variability (intracluster correlation) within dental clinic areas and SAMS, respectively. The most deprived (10th decile, SAMS level) 3- to 6-year-old children had an OR of 5.00 (95% CI 4.61-5.43) for dental caries experience (deft), compared with children in the 1st to 5th deciles. For older children and adolescents (≥7 years), the corresponding OR (DFT) was 2.25 (95% CI 2.15-2.35). Small geographical areas explained more of the variance in caries experience compared with the more aggregated level dental clinics. SES was more strongly related to the risk of dental caries experience than age and gender. In conclusion, the associations between SES and dental caries experience in Swedish children and adolescents were strong in the study and strongest in young children at a low level.

Inflammatory cytokine release from human peripheral blood mononuclear cells exposed to polyetheretherketone and titanium-6 aluminum-4 vanadium in vitro.

Objective To investigate the cytokine expression profiles of blood cells exposed to polyetheretherketone and titanium-6 aluminum-4 vanadium materials in vitro. Materials and methods Coin-shaped samples composed of titanium-6 aluminum-4 vanadium, polyetheretherketone, and blasted polyetheretherketone were manufactured. The surfaces of the coins were characterized using optical interferometry, scanning electron microscopy, and contact angle measurements. Peripheral blood mononuclear cells collected from 10 blood donors were cultured for one, three, and six days in the presence or absence of the coins, and then assayed for cytokine production. Quantification of the peripheral blood mononuclear cells attached to the coins was performed using confocal microscopy after immunofluorescence staining. Results The machined titanium-6 aluminum-4 vanadium coins had a smoother surface topography compared to the machined polyetheretherketone and blasted polyetheretherketone. The highest mean contact angle was noted for the blasted polyetheretherketone, followed by the machined polyetheretherketone and titanium-6 aluminum-4 vanadium. The peripheral blood mononuclear cells produced significantly more proinflammatory cytokines when exposed to the polyetheretherketone surface compared to the titanium-6 aluminum-4 vanadium surface, while the blasted polyetheretherketone induced the highest level of proinflammatory cytokine release from the peripheral blood mononuclear cells. Significantly more cells attached to both polyetheretherketone surfaces, as compared to the titanium-6 aluminum-4 vanadium surface. Conclusion Polyetheretherketone induces a stronger inflammatory response from peripheral blood mononuclear cells than does titanium-6 aluminum-4 vanadium. Surface topography has an impact on cytokine release from peripheral blood mononuclear cells.

The Immunomodulatory Properties of 2-Hydroxyethyl Methacrylate are Mediated by the NLRP3 Inflammasome.

PURPOSE: The methacrylate monomer 2-hydroxyethyl methacrylate (HEMA), commonly used in dentistry, has multiple effects on the immune system. This study examined whether HEMA affects the immune system by inducing formation of the NLRP3 inflammasome. MATERIALS AND METHODS: Human peripheral blood mononuclear cells (PBMCs) and the human monocyte cell line THP1 were cultured with or without 1000 µM HEMA. To block NLRP3 inflammasome activation, 130 mM KCl was also added to some of the cultures. For the in vivo studies, two different experimental setups were used. In the first experimental setup, mice were injected subcutaneously at the base of the tail with 20 µmol HEMA with or without 100 mM KCl. After 3 weeks, the animals were given an identical booster injection. Two weeks after the last injection, the mice were sacrificed and splenectomized. In the second experimental setup, HEMA (20 µmol), with or without 100 mM KCl, was injected subcutaneously into the tails of BALB/c mice. The mice were given two similar injections at 3-week intervals to allow evaluation of the local inflammation induced by HEMA. After the last inoculation, the injection site was examined daily for 4 days, after which the mice were sacrificed. RESULTS: Cultures of PBMCs and THP1 cells exposed to HEMA in vitro produced more IL-1ß and IL-18 than did control cells. Increased extracellular concentration of KCl inhibited the secretion of IL-1ß. HEMA exposure did not induce cytokine production in variants of the THP1 cell line unable to form the NLRP3 inflammasome. For the first experimental setup, the level of unstimulated basic splenocyte proliferation in vitro was significantly higher in cultures from mice exposed in vivo to HEMA only than in cultures from mice injected with HEMA plus KCl. In the second experimental setup of the in vivo studies, the HEMA-treated mice developed more pronounced inflammation at the site of injection compared to the group of mice given HEMA plus KCl. CONCLUSION: HEMA affects the immune system by inducing formation of the NLRP3 inflammasome.

Sublingual administration of 2-hydroxyethyl methacrylate enhances antibody responses to co-administered ovalbumin and Streptococcus mutans.

OBJECTIVE: The oral mucosa of patients undergoing dental procedures is often exposed to residual monomers leaking from incompletely cured acrylic resins. We investigated whether 2-hydroxyethyl methacrylate (HEMA) monomers applied to the sublingual mucosa in mice modulate the antibody responses towards co-administered ovalbumin (OVA) or live oral bacteria. MATERIAL AND METHODS: OVA, live mouse oral commensal Lactobacillus murinus or live human oral commensal Streptococcus mutans were administered sublingually with or without HEMA to BALB/c mice on four weekly occasions. One week after the last administration, the experiment was terminated and serum antibody levels were analyzed using ELISA. RESULTS: Significantly increased IgG and IgE anti-OVA antibody activity was found in the sera from mice immunized with OVA together with HEMA, as compared to mice immunized with OVA alone. Likewise, S. mutans together with HEMA induced an IgG anti-S. mutans antibody response that was significantly higher than the antibody response detected after application of S. mutans alone. No IgG anti-L. murinus antibody response was detected in mice immunized with L. murinus together with HEMA, as compared to the background activity. CONCLUSIONS: We report that HEMA monomers have adjuvant properties when sublingually administered in combination with OVA or S. mutans.