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Introduction: There are concerns that the COVID-19 pandemic exacerbated oral care inequities globally. In Sweden, declines in oral care utilization, particularly among certain regions and public clinics, suggest disproportionate impacts across population groups. Yet, the effects of the pandemic on oral care equity in Sweden remain unexplored, highlighting a critical gap in evidence to guide ongoing equity initiatives and strengthen future pandemic preparedness.

Objective: To examine changes in unmet oral care needs (UOCNs) inequities among Swedish adults before and during the pandemic, following an intersectional approach.

Methods: Data came from the 2018 and 2021 waves of a national survey, including 31,493 adults. Single-indicator and intersectional inequities were examined by intersectional analysis of individual heterogeneity and discriminatory accuracy across 48 groups defined by gender, age, education, income, and immigrant status.

Results: The prevalence of UOCNs increased during the pandemic. Notable shifts in single-indicator inequities included a decrease among immigrants but an increase among older adults. Modest increases were observed among individuals with low education and low income, while inequities decreased slightly for men and younger adults. The intersectional analysis revealed that inequities increased primarily among socially advantaged older adults, whereas decreases were more evident among immigrants and younger individuals facing other forms of social disadvantage. The discriminatory accuracy of both the single-indicator and intersectional inequities decreased during the pandemic, although intersectional models consistently showed slightly better accuracy.

Conclusions: Patterns of UOCNs inequities shifted during the pandemic, with increased intersectional inequities among socially privileged older adults and decreased inequities among immigrants. These findings may reflect Sweden’s unique pandemic context, which emphasized individual responsibility over restrictive measures and may have influenced how people approached health-related behaviors, including seeking oral care.

Background: Early gastrointestinal microbiota establishment is crucial for host metabolism and immune development, with delivery mode and breastfeeding playing key roles. Vaginal delivery promotes colonization by maternal vaginal and gut microbes, while Caesarean section delivery leads to exposures of environmental and skin-derived microbiota. Although maternal contributions have been studied, the role of paternal exposure in shaping infant microbiota remains underexplored. We hypothesized that both parents influence infant microbiota establishment and therefore investigated the contributions of maternal and paternal microbes, as well as delivery mode, on infant oral and fecal microbiota within 48 h of birth and at 1 month of age.

Methods: We analysed the gut and oral microbiota of 264 pregnant women, 261 partners, and 266 infants using 16S rRNA gene amplicon sequencing. α-diversity (Shannon Index) was compared using Wilcoxon tests, and β-diversity (Bray–Curtis dissimilarity) was assessed with PERMANOVA and PERMDISP. Principal component analysis (PCA) based on centered log-ratio (CLR)-transformed genus-level data was used for ordination and visualisation of taxonomic structure. Differentially abundant taxa across niches and delivery modes were identified using Kruskal–Wallis and Wilcoxon tests with false discovery rate (FDR) correction, followed by linear discriminant analysis (LDA). Putative amplicon sequence variant (ASV) sharing between infants and family members was explored using tree-based phylogenetic plots showing taxon presence and relative abundance across sample types. All analyses were performed in R using established packages.

Results: Adults showed significantly higher microbial α-diversity than infants in both gut and oral samples. β-diversity analyses revealed distinct microbial community structures influenced by ecological niches and delivery mode. Within the first 48 h after birth, differential abundance analyses identified Lactobacillus crispatus in meconium and Blautia_A in oral swabs enriched in vaginally delivered infants. L. crispatus also emerged as a key marker of the vaginal microbiota in our cohort-wide comparison, while Blautia, typically a gut-associated genus, was also detected in parental rectal and meconium samples. This co-occurrence may reflect transient microbial seeding during vaginal delivery. However, due to the limited resolution of 16S rRNA gene sequencing, these patterns suggest ecological overlap rather than definitive evidence of vertical transmission.

Conclusions: Our findings demonstrate that delivery mode influences early gut and oral microbiota composition, with vaginal delivery associated with taxa also found in maternal samples. While we observed microbial continuity between infant and parental niches, we could not clearly distinguish partner-specific contributions—likely due to the limited resolution of 16S rRNA gene sequencing. These results highlight the importance of delivery-associated exposures in early microbial development and underscore the need for high-resolution approaches to better resolve microbial acquisition within families.

Introduction: Infant formulas with reduced iron levels and lactoferrin (Lf) supplementation might mimic the beneficial effects of breast milk on the oral microbiome. This study aimed to investigate the impact of a bovine Lf-supplemented and iron-reduced formula on the oral microbiota in infants at 4, 6 and 12 months.

Methods: In a double-blind controlled trial, 6-week-old formula-fed infants were randomized to receive either a formula with reduced iron levels (2 mg/L) and Lf supplementation (1 g/L) (n = 72), the same formula without Lf (n = 72), or a standard formula (8 mg iron/L) (n = 36). A breast-fed reference group (n = 72) was also included. The oral microbiota was analyzed at 4 (n = 244), 6 (n = 216) and 12 (n = 229) months of age using the Oxford Nanopore Technology of the 16S rRNA gene annotation (eHOMD database).

Results: Neither the within- or between-group diversities nor overall microbiota pattern assessment revealed any statistically significant differences in microbiota composition between the formula groups. However, single species were significantly associated with specific formula-fed groups. At 6 months, breast-fed infants exhibited significantly lower species richness and distinct microbiota composition compared to the formula-fed groups.

Conclusions: The effects of reduced iron levels and lactoferrin supplementation of infant formula on the oral microbiome were inconclusive.

Background: Non-communicable diseases (NCDs) are a global health issue, posing a substantial burden on the individual, community, and public health. The risk of developing NCDs is influenced by a complex interplay between genetic, epigenetic, and environmental factors.

Methods: The NorthPop Birth Cohort Study (NorthPop) constitutes an infrastructure enabling cutting-edge research on the foundational pathways to NCDs in childhood, including allergic diseases and asthma, overweight/obesity, cognitive and neurodevelopmental dysfunction, gastrointestinal disorders, and caries. NorthPop aims at recruiting 10,000 families. Pregnant women and their partners residing in Västerbotten County, Sweden are eligible. Recruitment started in 2016 and is anticipated to end in 2025. Extensive data on parental, fetal and child health outcomes, lifestyle, diet, and environmental exposures are prospectively collected using web-based questionnaires in pregnancy and childhood until the children turn 7 years old. Urine samples are collected from the pregnant woman at gestational age 14–24 weeks. Blood samples are collected at gestational age 28 weeks. Placenta and cord blood are collected at birth. A breast milk sample is collected 1 month postpartum. Blood samples from the children are collected at 18 months and 7 years of age. Oral swabs and fecal samples are collected from the children within 48 h of birth, at 1, 9 and 18 months, 3 and 7 years of age. At age 7 years, children are invited to a follow-up visit, including measurements of weight, height, blood pressure, pulse, hand grip strength, working memory, skin prick test and saliva sampling. Additional measurements, such as sleep–wake and light exposure, and additional biological samples are collected in sub-cohorts. Permission for linkage to medical records and national registers e.g., the Swedish Pregnancy Register, the National Patient Register, the Longitudinal Integration Database for Health insurance and Labor market studies and the Swedish Prescribed Drug Register has been granted.

Discussion: Our multidisciplinary approach allows us to study how early life exposures, as well as parental health and lifestyle, influence future health in the offspring. Our results are anticipated to contribute to the understanding of disease risk and may inform future strategies aimed at risk reduction, highly significant for public health.

Trial registration: Retrospectively registered at Researchweb 11 November 2024 (project number 279272).

Eight pediatric oral nutritional supplements (ONSs) and 0.5% fat bovine milk were examined in vitro regarding their effect on the adhesion of three caries-related bacteria, Streptococcus mutans (strain CCUG 11877T), Lactobacillus gasseri (strain CCUG 31451), and Scardovia wiggsiae (strain CCUG 58090), to saliva-coated hydroxyapatite, as well as their pH and capacity to withstand pH changes. Bacteria were cultivated and radiolabeled. The adhesion assays used synthetic hydroxyapatite coated with whole or parotid saliva. Measurements of pH and titration of the products with HCl and NaOH were conducted in triplicate. Three ONSs promoted the S. mutans adhesion to saliva-coated hydroxyapatite (increase from 35% to >200%), supporting caries risk enhancement. S. wigssiae and L. gasseri adhered only to one and no ONS, respectively. Most supplements had limited buffering capacity to counteract acidification changes, suggesting their low capacity to neutralize acids, and one ONS showed a significant capacity to counteract basic changes, suggesting a high erosive potential. S. mutans adhesion was influenced by the ONS pH and volume NaOH added to reach pH 10. L. gasseri and S. wiggsiae adhesion was influenced by the ONSs' carbohydrate and fat content. Interdisciplinary efforts are needed to increase awareness and prevent the possible negative impact of ONSs on children's oral health.

Background: Oral health in Sweden is good at the population level, but seemingly with persisting or increasing inequities over the last decades. In 2008, a major Swedish reform introduced universal partial subsidies to promote preventive care and reduce the treatment cost for patients with extensive care needs. This study aimed to apply an intersectional approach to assess the impact of the 2008 subsidization reform on inequities in self-rated oral health among adults in Sweden over the period 2004–2018.

Methods: Data from 14 national surveys conducted over 2004–2018 were divided into three study periods: pre-reform (2004–2007), early post-reform (2008–2012) and late post-reform (2013–2018). The final study population was 118,650 individuals aged 24–84 years. Inequities in self-rated oral health were examined by intersectional analysis of individual heterogeneity and discriminatory accuracy across 48 intersectional strata defined by gender, age, educational level, income, and immigrant status.

Results: Overall, the prevalence of poor self-rated oral health decreased gradually after the reform. Gender-, education- and income-related inequities increased after the reform, but no discernible change was seen for age- or immigration-related inequities. The majority of intersectional strata experienced patterns of persistently or delayed increased inequities following the reform.

Conclusions: Increased inequities in self-rated oral health were found in most intersectional strata following the reform, despite the seemingly positive oral health trends at the population level. Applying an intersectional approach might be particularly relevant for welfare states with overall good oral health outcomes but unsuccessful efforts to reduce inequities.

Introduction: The main strategy to achieve equal provision of oral care in Sweden has been to offer partial subsidies for the adult population. However, their effects on unmet oral care needs (UOCNs) have not been extensively assessed.

Objective: This study used an intersectionality framework to examine 1) the overall frequency of UOCNs, 2) single-indicator inequities, and 3) intersectional inequities in total UOCNs and financial-related UOCNs (FUOCNs) in Sweden before and after implementation of a partial subsidization reform in 2008.

Methods: Data from 12 national surveys conducted over 2004 to 2018 were divided into 3 periods: prereform (2004 to 2007), early postreform (2008 to 2011), and late postreform (2012 to 2018). The analytic sample consisted of 98,177 respondents aged 24 to 84 y. Changes in the prevalence of UOCNs were estimated by inferential statistics. Single-indicator and intersectional inequities were examined by intersectional analysis of individual heterogeneity and discriminatory accuracy, across 48 strata defined by gender, age, educational level, income, and immigrant status. Results: The prevalence of total UOCNs and FUOCNs decreased significantly early after the reform, followed by a slight rebound. Relative inequities increased by education, income, and immigrant status after the reform and decreased for age. The discriminatory accuracy for both types of UOCNs was moderate and improved marginally but significantly with the inclusion of the intersectional strata. Most intersectional strata showed greater FUOCN inequities after the reform.

Conclusions: Contrary to expected, larger inequities in FUOCNs were identified in most intersectional strata after the reform. The moderate discriminatory accuracy suggested that Sweden could benefit from future strategies to foster equity that are universal but proportionately more intense among the intersectional strata with greater inequities (proportionate universalism). Knowledge Transference Statement: This analysis highlighted the benefit of adopting the principle of proportionate universalism as a strategy to reduce unmet oral care needs in Sweden. This would mean implementing universal strategies and specific support measures for the most vulnerable social groups as a future oral care policy change in Sweden.

Objectives: The goal of the Swedish oral healthcare system is to achieve good oral health and equitable access to care for the entire population. However, considerable inequities in oral health and care are evident and occur across a range of social dimensions. This study uses an intersectional approach to examine complex inequities in unmet oral care needs among adults in Sweden over the period 2004–2021.

Methods: Data were obtained from 14 Health on Equal Terms surveys conducted during 2004–2021. The final sample was 129 473 individuals aged 26–84 years. Applying intersectional analysis of individual heterogeneity and discriminatory accuracy, inequities in unmet oral care needs were estimated across 48 intersectional strata defined by gender, age, educational level, individual disposable income and immigrant status.

Results: A high risk of unmet oral care needs was found among strata consisting of immigrants and those with low income. However, being an immigrant and/or having a low income did not universally entail a high risk but varied by the social position along other axes, particularly age and education. The discriminatory accuracy was moderate.

Conclusion: Groups with certain social disadvantages are highly heterogeneous themselves. An intersectionality approach is important to prevent the risk of stigmatizing large heterogenous groups while failing to identify the most vulnerable strata. The discriminatory accuracy analysis suggested that further policy and/or interventions may be the most effective if approaching the whole population, combined with selected targeted interventions directed at the most disadvantaged social strata.

Taste perception is a well-documented driving force in food selection, with variations in, e.g., taste receptor encoding and glucose transporter genes conferring differences in taste sensitivity and food intake. We explored the impact of maternal innate driving forces on sweet taste preference and intake and assessed whether their children differed in their intake of sweet foods or traits related to sweet intake. A total of 133 single nucleotide polymorphisms (SNPs) in genes reported to associate with eating preferences were sequenced from saliva-DNA from 187 mother-and-child pairs. Preference and intake of sweet-, bitter-, sour-, and umami-tasting foods were estimated from questionnaires. A total of 32 SNP variants associated with a preference for sweet taste or intake at a p-value < 0.05 in additive, dominant major, or dominant minor allele models, with two passing corrections for multiple testing (q < 0.05). These were rs7513755 in the TAS1R2 gene and rs34162196 in the OR10G3 gene. Having the T allele of rs34162196 was associated with higher sweet intake in mothers and their children, along with a higher BMI in mothers. Having the G allele of rs7513755 was associated with a higher preference for sweets in the mothers. The rs34162196 might be a candidate for a genetic score for sweet intake to complement self-reported intakes.

Objectives: To test whether postulated subtypes of early childhood caries (ECC) are predictive of subsequent caries experience in a population-based cohort of Swedish children.

Methods: The study included children aged between 3 and 5 years at study entry with dental records available for at least 5 years of follow-up. Dental record data were retrieved from the Swedish Quality Registry for Caries and Periodontal disease (SKaPa) for the initial and follow-up visits. Participants who had ECC at study entry were assigned to one of five ECC subtypes (termed classes 1-5) using latent class modelling of tooth surface-level caries experience. Subsequent experience of caries was assessed using the decayed, missing and filled surfaces indices (dmfs/DMFS) at follow-up visits, and compared between ECC subtypes using logistic and negative binomial regression modelling.

Results: The study included 128 355 children who had 3 or more dental visits spanning at least 5 years post-baseline. Of these children, 31 919 had caries at the initial visit. Baseline ECC subtype was associated with differences in subsequent disease experience. As an example, 83% of children who had a severe form of ECC at age 5 went on to have caries in the permanent dentition by the end of the study, compared to 51% of children who were caries-free at age 5 (adjusted odds ratio of 4.9 for new disease at their third follow-up).

Conclusion: ECC subtypes assigned at a baseline visit are associated with differences in subsequent caries experience in both primary and permanent teeth. This suggests that the development and future validation of an ECC classification can be used in addition to current prediction tools to help identify children at high risk of developing new caries lesions throughout childhood and adolescence.