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Abstract Background Genes and culture are believed to interact, but it has been difficult to find direct evidence for the process. One candidate example that has been put forward is lactase persistence in adulthood, i.e. the ability to continue digesting the milk sugar lactose after childhood, facilitating the consumption of raw milk. This genetic trait is believed to have evolved within a short time period and to be related with the emergence of sedentary agriculture. Results Here we investigate the frequency of an allele (-13910*T) associated with lactase persistence in a Neolithic Scandinavian population. From the 14 individuals originally examined, 10 yielded reliable results. We find that the T allele frequency was very low (5%) in this Middle Neolithic hunter-gatherer population, and that the frequency is dramatically different from the extant Swedish population (74%). Conclusions We conclude that this difference in frequency could not have arisen by genetic drift and is either due to selection or, more likely, replacement of hunter-gatherer populations by sedentary agriculturalists.

Abstract Background Geographic distribution of the genetic diversity in domestic animals, particularly mitochondrial DNA, has often been used to infer centers of domestication. The underlying presumption is that phylogeographic patterns among domesticates were established during, or shortly after the domestication. Human activities are assumed not to have altered the haplogroup frequencies to any great extent. We studied this hypothesis by analyzing 24 mtDNA sequences in ancient Scandinavian dogs. Breeds originating in northern Europe are characterized by having a high frequency of mtDNA sequences belonging to a haplogroup rare in other populations (HgD). This has been suggested to indicate a possible origin of the haplogroup (perhaps even a separate domestication) in central or northern Europe. Results The sequences observed in the ancient samples do not include the haplogroup indicative for northern European breeds (HgD). Instead, several of them correspond to haplogroups that are uncommon in the region today and that are supposed to have Asian origin. Conclusion We find no evidence for local domestication. We conclude that interpretation of the processes responsible for current domestic haplogroup frequencies should be carried out with caution if based only on contemporary data. They do not only tell their own story, but also that of humans.

Objectives: The coronavirus disease 2019 (COVID-19) pandemic prompted a rapid shift from in-person to virtual learning in dental education. This study aims to assess the perceptions of virtual education learning among dental residents and faculty and employ regulatory focus theory (RFT) to understand the impact of motivational orientations on virtual learning during the COVID-19 pandemic., Methods: In total, 46 dental residents and 10 faculty members in a dental institution participated in the study (June-August 2021). Questionnaires were used to obtain data on demographics, perceptions of virtual learning, burnout, and RFT types (promotion and prevention focus). Multiple regression analyses were used to examine factors associated with perceptions of virtual learning and burnout., Results: Overall, 70% of residents and 44% of faculty found virtual learning effective. Younger residents with less experience preferred virtual learning more than their older, experienced peers. Residents trained outside the U.S. and Canada favored in-person learning more than those trained within. Furthermore, residents with a higher promotion focus score found virtual learning more interactive for didactic courses. Additionally, 52% of residents experienced burnout, with a higher incidence among females ( p = 0.044)., Conclusions: Virtual learning is well received by dental residents and faculty, with potential for continued use post-pandemic. Future efforts should focus on creating an inclusive and supportive educational environment that meets the motivational and well-being needs of dental residents and faculty.

Objectives: This systematic review compares the impact of ball and locator attachments on marginal bone loss in implant-retained overdentures in completely edentulous patients., Method and Materials: Following PRISMA guidelines, health science librarians completed literature searches from inception to 17 March 2023 in seven databases. There were 15,686 items exported to EndNote from Embase.com, CINAHL (EBSCO), Cochrane Library, Ovid MEDLINE-ALL, PubMed, Scopus, and Web of Science. Hand-searching added four more articles. After deduplication, 6,756 items were screened for eligibility. Twenty-nine studies were assessed by full text, of which ten studies, involving 424 subjects, were included in the review. Risk of bias assessment was conducted using the Cochrane risk-of-bias tool and the Newcastle-Ottawa scale. A meta-analysis was performed to synthesize and analyze the collective data from the selected studies., Results: The included studies used diverse methodologies, implant systems, and loading protocols. Most studies reported no significant difference in marginal bone loss between ball and locator attachments. The meta-analysis revealed high heterogeneity., Conclusion: The results of this systematic review suggest that ball and locator attachments exhibit similar performance in terms of marginal bone loss in implant-retained overdentures. However, the limited number, risk of bias, and heterogeneity of studies highlight the need for standardized research designs and larger sample sizes in future investigations to draw more definitive conclusions.

Background and Objectives : Tooth whitening is a relatively conservative and effective option to treat discolored teeth. However, questions remain whether in-office or at-home tooth whitening products with short treatment durations are as effective and stable as products with longer treatment durations. Materials and Methods : Forty human third molars with intact enamel surfaces were divided into four groups of ten each, subjected to discoloration challenges with coffee for 60 h, and they were treated with four professional tooth whitening systems: two for take-home use-6% hydrogen peroxide for 30 min/d for a total of 7 h in 14 days (HP6), 10% carbamide peroxide for 10 h/d for 140 h in 14 days (CP10), as well as two for in-office use-35% HP for 10 min × 3 (HP35) for a total of 30 min and 40% HP for 20 min × 3 (HP40) for a total of 60 min. Teeth colors were assessed in the CIE L*a*b* color space with a spectrophotometer immediately and six months after whitening treatments. Surface roughness (Sa) for the treated and untreated enamel surfaces of the teeth in all groups were evaluated with a three-dimensional laser scanning microscope after six months. Results : No significant differences were found between HP6 and CP10 groups immediately after whitening (∆ E 10.6 ± 1.6 vs. 11.4 ± 1.7, p > 0.05) and at six months after treatments (∆ E 9.0 ± 1.9 vs. 9.2 ± 2.5, p > 0.05), or between HP35 and HP40 groups immediately after whitening (∆ E 5.9 ± 1.2 vs. 5.3 ± 1.7, p > 0.05) and at six months after treatments (∆ E 7.2 ± 1.6 vs. 7.7 ± 1.3, p > 0.05). The two at-home whitening systems achieved significantly better whitening outcomes than the two in-office products immediately after whitening ( p < 0.05). However, at six months after treatments, the differences between at-home and in-office treatments had narrowed significantly ( p > 0.05). There were no statistically significant differences with respect to the Sa values between the treated and untreated surfaces ( p > 0.05). Conclusions : Tooth whitening products in the same product category have similar whitening efficacies, despite significant differences in treatment durations (7 vs. 140 h, and 30 min vs. 60 min, respectively). Take-home products achieved better whitening outcomes than in-office products, but they needed 14 to 280 times longer treatment durations.

Objective: To systematically review the effect of electronic cigarette (e-cigarette) use on clinical, radiographic, and immunologic peri-implant parameters in males., Study Design: A comprehensive search of indexed databases was conducted to identify studies reporting data on both e-cigarette users and nonsmokers with implant-supported prosthesis with ≥1-year in function, up to May 2022. Marginal bone loss (MBL), probing depth (PD), plaque index (PI), and bleeding on probing (BOP) were recorded. Peri-implant sulcular fluid volume (PISF), tumor necrosis factor alpha (TNF-α) and interleukin 1β (IL-β) levels were also assessed. A meta-analysis was performed using random-effect models to determine the effect of e-cigarette use in primary and secondary outcomes., Results: Four cross-sectional studies were included with a total of 327 participants (165 e-cigarette users and 162 nonsmokers). All studies showed greater MBL, PI, PD, and lower BOP in e-cigarette users compared with never smokers. The meta-analysis indicated significant heterogeneity for all outcomes except MBL for distal implant surfaces, with the mean difference between e-cigarette users and nonsmokers of 0.89 mm (95% CI: 0.67-1.11, P < .01). The PISF volume, TNF-α, and IL-1β levels were increased in e-cigarette users (P < .01) with no heterogeneity present between studies., Conclusions: E-cigarette use shows a negative effect on clinical, radiographic, and immunologic parameters of dental implants., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Objective: To assess the effect of Nystatin on Candida albicans and Streptococcus mutans duo-species biofilms using an in vitro cariogenic biofilm model., Design: Biofilms were formed on saliva-coated hydroxyapatite discs under high sugar challenge (1 % sucrose and 1 % glucose), with inoculation of 10 5 CFU/ml S. mutans and 10 3 CFU/ml C. albicans. Between 20 and 68 h, biofilms were treated with 28,000 IU Nystatin solution, 5 min/application, 4 times/day, to mimic the clinical application. Biofilm's three-dimensional structure was assessed using multi-photon confocal microscopy. The expression of C. albicans and S. mutans virulence genes was assessed via real-time PCR. Duplicate discs were used in 3 independent repeats. t-test and Mann-Whitney U test were used to compare outcomes between treatment and control group., Results: Nystatin treatment eliminated C. albicans in biofilms at 44 h. Nystatin-treated group had a significant reduction of biofilm dry-weight and reduced S. mutans abundance by 0.5 log CFU/ml at 44 and 68 h (p < 0.05). Worth noting that biomass distribution across the vertical layout was altered by Nystatin treatment, resulting in less volume on the substrate layers in Nystatin-treated biofilms compared to the control. Reduction of microcolonies size and volume was also observed in Nystatin-treated biofilms (p < 0.05). Nystatin-treated biofilms formed unique halo-shaped microcolonies with reduced core EPS coverage. Furthermore, Nystatin-treated biofilms had significant down-regulations of S. mutans gtfD and atpD genes (p < 0.05)., Conclusions: Nystatin application altered the formation and characteristics of C. albicans and S. mutans duo-species biofilms. Therefore, developing clinical regimens for preventing or treating dental caries from an antifungal perspective is warranted., Competing Interests: Conflict of interest statement The authors declared no potential conflicts of interest., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Aim: To conduct a systematic review and to evaluate the clinical parameters for periodontal diseases in individuals with cleft lip and/or palate (CL/P)., Design: The authors searched six indexed databases without any linguistic limitation through July 2021. The eligibility criteria were observational studies that compared the periodontal clinical measures of individuals with CL/P to those without CL/P. A meta-analysis was conducted using random-effects models with inverse variance weighting., Results: The literature search generated 1277 records, and 40 full-text articles were reviewed. Twenty-three studies comprising 3235 individuals from four continents fulfilled our selection criteria. The meta-analysis revealed a significant difference in mean plaque index scores (MD = 0.31, 95% CI = 0.22, 0.41), gingival index scores (MD = 0.50, 95% CI = 0.24, 0.77), and periodontal pocket depth (MD = 0.64, 95% CI = 0.12, 1.16) between individuals with and without CL/P. A slight increase in clinical attachment loss was detected among individuals with CL/P; however, such an increase may have little clinical significance., Conclusions: As age is positively related to periodontal disease progression, and individuals with CL/P are more likely to present with more plaque accumulation and gingival inflammation, clinicians should reinforce preventive dental care from an early age., (© 2022 BSPD, IAPD and John Wiley & Sons Ltd.)

Background: Everyday people die unnecessarily from opioid overdose-related addiction. Dentists are among the leading prescribers of opioid analgesics. Opioid-seeking behaviors have been linked to receipt of initial opioid prescriptions following the common dental procedure of third molar extraction. With each opioid prescription, a patient's risk for opioid misuse or abuse increases. With an estimated 56 million tablets of 5 mg hydrocodone annually prescribed after third molar extractions in the USA, 3.5 million young adults may be unnecessarily exposed to opioids by dentists who are inadvertently increasing their patient's risk for addiction., Methods: A double-blind, stratified randomized, multi-center clinical trial has been designed to evaluate whether a combination of over-the-counter non-opioid-containing analgesics is not inferior to the most prescribed opioid analgesic. The impacted 3rd molar extraction model is being used due to the predictable severity of the post-operative pain and generalizability of results. Within each site/clinic and gender type (male/female), patients are randomized to receive either OPIOID (hydrocodone/acetaminophen 5/300 mg) or NON-OPIOID (ibuprofen/acetaminophen 400/500 mg). Outcome data include pain levels, adverse events, overall patient satisfaction, ability to sleep, and ability to perform daily functions. To develop clinical guidelines and a clinical decision-making tool, pain management, extraction difficulty, and the number of tablets taken are being collected, enabling an experimental decision-making tool to be developed., Discussion: The proposed methods address the shortcomings of other analgesic studies. Although prior studies have tested short-term effects of single doses of pain medications, patients and their dentists are interested in managing pain for the entire post-operative period, not just the first 12 h. After surgery, patients expect to be able to perform normal daily functions without feeling nauseous or dizzy and they desire a restful sleep at night. Parents of young people are concerned with the risks of opioid use and misuse, related either to treatments received or to subsequent use of leftover pills. Upon successful completion of this clinical trial, dentists, patients, and their families will be better able to make informed decisions regarding post-operative pain management., Trial Registration: ClinicalTrials.gov NCT04452344 . Registered on June 20, 2020., (© 2022. The Author(s).)