Early life stress is associated with earlier emergence of permanent molars.

Exposure to adversity can accelerate biological aging. However, existing biomarkers of early aging are either costly and difficult to collect, like epigenetic signatures, or cannot be detected until late childhood, like pubertal onset. We evaluated the hypothesis that early adversity is associated with earlier molar eruption, an easily assessed measure that has been used to track the length of childhood across primates. In a preregistered analysis (n = 117, ages 4 to 7 y), we demonstrate that lower family income and exposure to adverse childhood experiences (ACEs) are significantly associated with earlier eruption of the first permanent molars, as rated in T2-weighted magnetic resonance images (MRI). We replicate relationships between income and molar eruption in a population-representative dataset (National Health and Nutrition Examination Survey; n = 1,973). These findings suggest that the impact of stress on the pace of biological development is evident in early childhood, and detectable in the timing of molar eruption.

The association of food insecurity with tooth decay and periodontitis among middle-aged and older adults in the United States and Korea.

INTRODUCTION: Food insecurity is an important social determinant of health, but there is limited understanding of its relationship with adult oral health. This study examined the associations between food insecurity and dental diseases (caries and periodontitis) among middle-aged and older adults in the United States and South Korea. METHODS: This study focused on middle-aged (40-59 years) and older adults (>59 years) who participated in the 2011-2016 US National Health and Nutrition Examination Surveys (NHANES) or the 2013-2015 South Korean NHANES. The exposure was food insecurity severity (food secure/early-stage food insecurity/middle-stage or severe food insecurity) assessed using the 18-item US Household Food Security Survey Module. The two outcomes were any untreated tooth decay and periodontitis measured using the Modified Community Periodontal Index of Treatment Needs. Covariate-adjusted odds ratios (OR) with 95% confidence intervals (CI) were generated using multivariable logistic regression models. RESULTS: Middle or severe food insecurity was associated with significantly higher odds of having untreated tooth decay than no food insecurity, but only among middle-aged adults in the United States (OR: 1.4, 95% CI 1.2, 1.9; P = .037) and Korea (OR = 1.8; 95% CI:1.0, 3.2; P = .036) and older adults in the United States (OR: 2.6, 95% CI 1.7, 4.0; P < .001). The associations between food insecurity and periodontitis were inconsistent across age group and country. CONCLUSION: Differing cultural norms and access to dental services in the United States and South Korea may influence the relationship between food insecurity and oral health. Future research should explore how addressing food insecurity could help to promote the oral health of middle-aged and older adults in diverse sociocultural contexts.

Effectiveness of digital impressions in a predoctoral clinical curriculum.

AIM: The purpose of the present study was to investigate the effectiveness of digital impressions made by 3rd and 4th year dental students using a retrospective record review at one USA dental school during a 1-year period. MATERIALS AND METHODS: After reviewing patient records related to quality assurance, 125 digital impressions and the produced restorations were evaluated. Effectiveness and acceptability of digital impressions and restorations were associated with students' educational level, number of prepared teeth scanned, type of produced restoration, and restorative material used. Fisher's exact and chi-square tests were used for the statistical analysis. All dental students had previous experience of the digital curriculum in their preclinical education. RESULTS: A total of 91% of the digital impressions were acceptable, and 80% of the produced restorations had clinically acceptable margins. Impression approval and restoration acceptance were not affected by students' educational level, number of preparations or restoration type. Restoration acceptance was significantly affected by restorative material (P = 0.039), with higher rates of acceptable marginal integrity found with glass-ceramic and zirconia materials. CONCLUSIONS: Within the parameters of the present study, 3rd and 4th year dental students, after having extensive education in the preclinical curriculum, can utilize digital impressions effectively for clinical practice. The results show that with adequate educational experiences, dental students can use digital impressions effectively for clinically acceptable restorations. Dental schools can and should educate students in digital dentistry.

A survey of US dental schools on predoctoral implant curricula with emphasis on diagnosing and treating implant complications.

STATEMENT OF PROBLEM: Implant complications have been reported to occur at high rates and frequencies. Whether these high rates are observed in predoctoral implant programs and whether future dentists are educated to diagnose and treat implant complications is unknown. PURPOSE: The purpose of this study was to analyze and report the results of a survey on US predoctoral curricula related to implant treatment and with an emphasis on diagnosing and treating implant complications. MATERIAL AND METHODS: A 26-question survey was distributed to all (66) US dental schools. In addition to 3 questions regarding descriptive information about each school, 13 questions were used to calculate a curriculum composite score that was used to assess the quality of the school's implant curriculum. The remaining survey topics and number of questions included frequency of complications (2), tracking and types of complications (6), and school-reported student preparedness to identify or treat implant complications (2). A Kruskal-Wallis test was used to evaluate the relationship between the curriculum composite scores and student preparedness to diagnose and treat implant complications. RESULTS: Twenty-eight schools responded to the survey for a response rate of 42.4%, and 23 schools completed the entire survey (completion rate 34.8%). Fifteen schools (65.2%) reported methods of recording implant complications, and 8 of 23 schools (34.8%) reported methods of assessing student knowledge in recognizing implant complications. Only 2 schools reported methods of assessing student preparedness to treat implant complications. Most implant complications were mechanical (64.3%), followed by biological (28.6%) and esthetic (7.1%). The prostheses associated with the most complications were implant overdentures (39.1%), followed by single crowns (34.8%) and fixed partial dentures (4.3%). A positive relational trend was observed between reported student preparedness to recognize and treat implant complications and curriculum composite scores. CONCLUSIONS: Within the limitation of this survey-based study, implant curricula in US dental schools should consider improving the scope of teaching the diagnosis and treatment of implant complications. The implant complications observed at US dental schools showed similar trends to those reported in the literature.

Oral health behaviours and dental caries in low-income children with special healthcare needs: A prospective observational study.

BACKGROUND: Dental caries is a significant public health problem for low-income children with special healthcare needs (CSHCN). AIM: We evaluated associations between oral health behaviours (eg diet, fluoride, dental care) and dental caries for CSHCN enrolled in Medicaid, a health insurance programme for low-income populations that provides comprehensive dental coverage for children. DESIGN: We recruited 116 CSHCN ages 7-20 years from Medicaid enrolment files in Washington state, USA. Caregivers completed a 166-item questionnaire, and children received a dental screening. The outcome was dental caries, defined as total pre-cavitated, decayed, missing or filled tooth (PDMF) surfaces. We ran log-linear regression models and generated prevalence rate ratios (PRR). RESULTS: The mean age of study participants was 12.4 ± 3.1 years, 41.4% were female, and 38.8% were white. The mean PDMF surfaces were 6.4 ± 9.4 (range: 0-49). Only sugar-sweetened beverage intake was significantly associated with dental caries. CSHCN who consumed >4 sugar-sweetened beverages per week were significantly more likely to have dental caries than those who consumed no sugar-sweetened beverages (PRR: 2.58; 95% CI: 1.37, 4.85; P < .01). CONCLUSION: Sugar-sweetened beverages are an important target for future behavioural interventions aimed at preventing dental caries in low-income CSHCN.

Mortality After Discontinuation of Primary Care-Based Chronic Opioid Therapy for Pain: a Retrospective Cohort Study.

BACKGROUND: Despite known risks of using chronic opioid therapy (COT) for pain, the risks of discontinuation of COT are largely uncharacterized. OBJECTIVE: To evaluate mortality, prescription opioid use, and primary care utilization of patients discontinued from COT, compared with patients maintained on opioids. DESIGN: Retrospective cohort study of patients with chronic pain enrolled in an opioid registry as of May 2010. PARTICIPANTS: Patients with chronic pain enrolled in the opioid registry of a primary care clinic at an urban safety-net hospital in Seattle, WA. MAIN OUTCOMES AND MEASURES: Discontinuation from the opioid registry was the exposure of interest. Pre-specified main outcomes included mortality, prescription and primary care utilization data, and reasons for discontinuation. Data was collected through March 2015. KEY RESULTS: The study cohort comprised 572 patients with a mean age of 54.9 ± 10.1 years. COT was discontinued in 344 patients (60.1%); 254 (73.8%) discontinued patients subsequently filled at least one opioid prescription in Washington State, and 187 (54.4%) continued to visit the clinic. During the study period, 119 (20.8%) registry patients died, and 21 (3.7%) died of definite or possible overdose: 17 (4.9%) discontinued patients died of overdose, whereas 4 (1.75%) retained patients died of overdose. Most patients had at least one provider-initiated reason for COT discontinuation. Discontinuation of COT was associated with a hazard ratio for death of 1.35 (95% CI, 0.92 to 1.98, p = 0.122) and for overdose death of 2.94 (1.01-8.61, p = 0.049), after adjusting for age and race. CONCLUSIONS: In this cohort of patients prescribed COT for chronic pain, mortality was high. Discontinuation of COT did not reduce risk of death and was associated with increased risk of overdose death. Improved clinical strategies, including multimodal pain management and treatment of opioid use disorder, may be needed for this high-risk group.

Determination of Elastic Modulus in Mouse Bones Using a Nondestructive Micro-Indentation Technique Using Reference Point Indentation.

The determination of the elastic modulus of bone is important in studying the response of bone to loading and is determined using a destructive three-point bending method. Reference point indentation (RPI), with one cycle of indentation, offers a nondestructive alternative to determine the elastic modulus. While the elastic modulus could be determined using a nondestructive procedure for ex vivo experiments, for in vivo testing, the three-point bending technique may not be practical and hence RPI is viewed as a potential alternative and explored in this study. Using the RPI measurements, total indentation distance (TID), creep indentation distance, indentation force, and the unloading slope, we have developed a numerical analysis procedure using the Oliver-Pharr (O/P) method to estimate the indentation elastic modulus. Two methods were used to determine the area function: (1) Oliver-Pharr (O/P-based on a numerical procedure) and (2) geometric (based on the calculation of the projected area of indentation). The indentation moduli of polymethyl methacrylate (PMMA) calculated by the O/P (3.49-3.68 GPa) and geometric (3.33-3.49 GPa) methods were similar to values in literature (3.5-4 GPa). In a study using femurs from C57Bl/6 mice of different ages and genders, the three-point bending modulus was lower than the indentation modulus. In femurs from 4 to 5 months old TOPGAL mice, we found that the indentation modulus from the geometric (5.61 ± 1.25 GPa) and O/P (5.53 ± 1.27 GPa) methods was higher than the three-point bending modulus (5.28 ± 0.34 GPa). In females, the indentation modulus from the geometric (7.45 ± 0.86 GPa) and O/P (7.46 ± 0.92 GPa) methods was also higher than the three-point bending modulus (7.33 ± 1.13 GPa). We can conclude from this study that the RPI determined values are relatively close to three-point bending values.

Temperament as a Predictor of Nitrous Oxide Inhalation Sedation Success.

Little is known about implications of temperament for children who receive nitrous oxide inhalation sedation (N2O/O2) for dental care. The aim of this study was to investigate whether child temperament is associated with success in N2O/O2. Child-caregiver dyads were enrolled from patients aged 36-95 months receiving dental care with N2O/O2 at a university-based pediatric dental clinic. To assess child temperament, 48 caregivers completed the Children's Behavior Questionnaire Short Form. Patient behavior was abstracted from Frankl scores recorded in the patient's chart. The overall behavioral failure rate was 15% (n = 7/48). There was no significant difference in sedation outcome associated with sex, health, insurance status, or complexity of treatment provided. Sedation outcome was significantly associated with the broad temperament domain of Effortful Control and its subscales Attentional Focusing and Inhibitory Control. The Negative Affectivity subscales of Frustration, Sadness, and Soothability and the Extraversion/Surgency subscales Activity and Impulsivity were also significantly associated with sedation outcome. The results of this study suggest that Effortful Control is associated with behavior during dental treatment with N2O/O2. The subscales of Attention Focusing, Inhibitory Control, Frustration, Fear, Sadness, Soothability, Activity, and Impulsivity may also be important determinants of child behavior during dental treatment.

Racial disparities in orthodontic service use for Medicaid-enrolled children: An evaluation of the Washington Medicaid program.

INTRODUCTION: We assessed the relationship between race and orthodontic service use for Medicaid-enrolled children. METHODS: This cross-sectional study focused on 570,364 Medicaid-enrolled children in Washington state, ages 6 to 19 years. The main predictor variable was self-reported race (white vs nonwhite). The outcome variable was orthodontic service use, defined as children who were preauthorized for orthodontic treatment by Medicaid in 2012 and subsequently received orthodontic records and initiated treatment. Logistic regression models were used to test the hypothesis that nonwhites are less likely to use orthodontic care than are whites. RESULTS: A total of 8223 children were approved by Medicaid for orthodontic treatment, and 7313 received records and began treatment. Nonwhites were significantly more likely to use orthodontic care than were whites (odds ratio [OR] = 1.18; 95% confidence interval [CI] = 1.02, 1.36; P = 0.031). Hispanic nonwhite children were more likely to use orthodontic care than were non-Hispanic white children (OR = 1.42; 95% CI = 1.18, 1.70; P <0.001). CONCLUSIONS: In 2012, nonwhite children in the Washington Medicaid program were significantly more likely to use orthodontic care than were white children. The Washington Medicaid program demonstrates a potential model for addressing racial disparities in orthodontic service use. Future research should identify mechanisms underlying these findings and continue to monitor orthodontic service use for minority children in Medicaid.

Tooth wear and the role of salivary measures in general practice patients.

OBJECTIVES: The goal of this study was to investigate the association between tooth wear and salivary measures in a random sample of patients from practices of dentist members of a practice-based research network. MATERIALS AND METHODS: Patients completed a questionnaire on oral self-care, health, dietary habits, medications, and socio-demographic variables. Six salivary characteristics (consistency, resting salivary flow, resting salivary pH, stimulated salivary flow, stimulated salivary pH, and buffering capacity) were measured, and a dental examination included categorizing patients according to the dentist's judgment of the degree of tooth wear (i.e., none/minimal, some, or severe/extreme). Bivariate and multinomial logistic regression models were used to relate salivary characteristics and other factors to the outcome of tooth wear. RESULTS: Data are reported from 1,323 patients (age range 16-97 years) from 61 practices. Patient age, gender, number of teeth, and perception of dry mouth were associated with tooth wear, but salivary and dietary factors were either weakly or not related. CONCLUSIONS: The findings of this cross-sectional assessment suggest that using these salivary tests and dietary assessments in real-life clinical settings is unlikely to be useful in assessing tooth wear risk. Suggestions are offered about risk assessment for tooth wear. CLINICAL RELEVANCE: Assessing a dental patient's risk of tooth wear using salivary measures and dietary assessments as described is not recommended for general dental practice until stronger evidence exists indicating its utility.

Person-Centered Care in Dental Hygiene Education: Incorporation and evaluation of person-centered care in the curriculum.

Purpose Patient and person-centered care are often used interchangeably. The abbreviation PCC is used in this paper in instances where patient/person centered care reflects the definition of person-centeredness. The purpose of this study was to assess how PCC is taught and evaluated in entry-level dental hygiene education programs to prepare graduates for future collaborations with oher health care pprofessionals in a wide range of practice settings.Methods A cross-sectional study was conducted using a 10-item survey emailed to directors of 325 accredited, entry-level dental hygiene education programs in the United States in December 2021. Descriptive statistics were calculated for all variables. Associations with curriculum settings, teaching, and evaluation methods for PCC, according to program degrees granted, were tested with Chi-square and Fisher's Exact tests.Results The response rate was 23% (n=75). Seventy percent offered an associate degree (AS) and 29% offered a baccalareate degree (BS); 42% reported more than half of their curriculum is allocated to teaching PCC. Didactic lectures (100%), case presentations (97%), and clinical instruction (97%) were the most common methods used for teaching PCC. Baccalaureate programs used external rotations more than associate programs for teaching and evaluation of PCC (84.2% vs. 45.5%; p<0.01). The most common PCC terms used in Quality Assurance Plans included providing individualized care (99%) and delivering evidence-based care (91%). Ninety-three percent strongly agree-agree that teaching PCC prepares graduates for working in different settings (e.g., schools, nursing homes, etc.), and 82% strongly agree-agree that PCC prepares graduates to work with a variety of providers.Conclusion The allocation of curricula time for PCC varied widely across respondents. Conversely, the majority felt their graduates were well-prepared to work in different settings where both PCC and IPP are likely to be practiced. This study serves as a baseline for further analysis of how dental hygiene education is preparing graduates for future practice settings.

Kansas Extended Care Permit III Providers: A descriptive study.

Purpose Forty-two states to date have passed legislation to expanded the role of dental hygienists for improved access to basic oral health services for underserved populations. Recent legislative changes in the state of Kansas have created the Extended Care Permit (ECP) I, II, and III designations. The purpose of this study was to examine the experiences of registered dental hygienists in Kansas holding ECP III certificates.Methods Secondary data analysis was performed utilizing data collected from an ECP provider survey conducted in 2021. Dental hygienists in Kansas holding an Extended Care Permit III (n=88) were sent a 39-item electronic survey and informed consent was obtained prior to beginning the survey. Descriptive data analyses consisted of frequency distributions and percentages. Inferential data analysis consisted of Fisher's Exact and Chi-Square tests to evaluate associations between ECP III demographics, practice characteristics, and services provided.Results A total of 22 responses were received for a 25% response rate. The majority of the respondents (77%) were employed by a Safety Net Clinic. The practice settings reporting the highest percentage of ECP III services during the period of data collection were school-based settings, using portable equipment (68%). No associations were found between ECP III personal and practice characteristics and the provision of services specific to the ECP III permit.Conclusion Results suggest that a low percentage of ECP III permit holders are providing ECP III-specific services. Considering these findings and the outcomes of previous studies, there is speculation that barriers continue to exist that prevent permit holders from performing ECP III-specific services and providing dental hygiene services to the fullest extent of an ECP license.

Examining the mental health of university students: A quantitative and qualitative approach to identifying prevalence, associations, stressors, and interventions.

OBJECTIVE: To identify the prevalence of anxiety, depression, and suicidal ideation that would place university students at risk for mental health disorders. To explore the source of stressors and possible interventions that may benefit student mental health in a university setting. PARTICIPANTS: University students (n = 483) who had been learning remotely due to the COVID-19 pandemic. METHODS: A mixed-methods cross-sectional survey was administered in 2020. RESULTS: Students were at an increased rate of depression, anxiety and suicidal ideation as compared to the general population. Female gender, lack of social support, living alone, being a first-generation college student and COVID-19 were significantly associated with mental health disorders. Stressors were identified and categorized into themes and interventions were recognized that may improve student well-being. CONCLUSION: Students enrolled in university programs appear to experience significant amounts of anxiety, depression, and suicidal ideation. Additional mental health education, resources, and support is needed.

Comparison of Pediatric Dentistry Under General Anesthesia in a Surgery Center vs a Hospital.

OBJECTIVE: Pediatric patients who undergo general anesthesia (GA) for dentistry may be treated in different venues. This retrospective study compared patients treated in an ambulatory surgery center (ASC) to those treated in a hospital operating room (H-OR). The 2-venue model was also compared with a historical hospital-only model. METHODS: Twelve months of data were collected via records review: patient demographics, American Society of Anesthesiology (ASA) classification, and medical comorbidities. Data from patients treated at the H-OR 10 years prior were referenced for comparison. RESULTS: Between July 2017 and June 2018, 1148 patients were treated: 635 at the ASC and 513 at the H-OR. The most common age range for both venues was 3 to 8 years. Of all the ASC patients, 78% were ASA I, while 48% of H-OR patients were ASA III (P < .001). The number of patients treated with the 2-venue model represented a 240% annual increase compared with those treated historically using the hospital-only model. CONCLUSION: Because of differences in patient medical comorbidities, both the ASC and H-OR are needed to adequately address the needs of pediatric dental patients who require GA. Treating healthy patients in an ASC also creates increased capacity in the H-OR to better accommodate those with higher medical acuity.

Practice Ownership Intentions of Pediatric Dentistry Residents and the Influence of Educational Debt.

Purpose: The purpose of this study was to investigate the interest in practice ownership among pediatric dentistry residents and influencing factors, particularly educational debt. Methods: An invitation to participate in an anonymous survey was sent to 933 pediatric dentistry residents training in the United States in the spring of 2020. Results: The survey response rate was 32.9 percent. Of the respondents, 61.2 percent reported being extremely or very interested in practice ownership and 49.8 percent anticipated becoming a practice owner within five years of graduation. An inverse relationship was seen between one's level of comfort in assuming a business loan to acquire a practice and having an educational debt burden of $400,000 or greater (P=0.002). Practice management preparation was the most common concern related to future practice ownership. Those feeling completely, very, or moderately prepared to manage a dental practice were over 40 percent more likely to be extremely or very interested in practice ownership than were those who felt slightly or not at all prepared (P<0.001). Conclusions: There appears to be broad interest in practice ownership among pediatric dentistry residents. Relatively high educational debt may negatively influence future practice ownership, but it may be less influential than other factors.

Using learning management software data to compare students' actual and self-reported viewing of video lectures.

PURPOSE: Student engagement is typically measured by class attendance and questionnaires. Learning management systems (LMS) provide additional sources of objective data that can evaluate student performance. This study compared dental students' self-report of course video viewing with LMS data. METHODS: Dental students in a 2018 flipped pediatric dentistry course were given a questionnaire after course completion that captured self-reported course video viewing. Student data and time spent on videos were extracted from the LMS and matched to the questionnaire. McNemar's test evaluated differences between self-reported and matching LMS data. RESULTS: Of the 109 enrolled students, 99 (91%) completed the questionnaire. Most students self-reported that they watched more than half of the videos (71%), re-watched at least once (89%), and watched at times other than 8 a.m.-5 p.m. (80%). Of the 104 students with data from the LMS, 40% of students watched more than half of the videos, 49% re-watched at least one video, and 60% watched between 8 a.m.-5 p.m. LMS data showed 14 (13%) students did not watch any videos. Significant differences were found between self-reported video viewing and matched LMS video data in (1) percentage of videos watched, (2) number of times videos were re-watched, and (3) most frequent time for watching the videos (p < 0.001 for all). CONCLUSION: Technology is a tool that helps instructors more accurately track students' study habits compared to observation or self-report. When evaluating time spent watching videos via an LMS, students tend to overestimate the amount of viewing time.

Associations of Self-Reported Oral Health Quality of Life with Actual Oral Health Status in Children.

Purpose: Quality of life is considered a component of patient centered care. The purpose of this study was to examine the relationship between self-reported oral health related quality of life (OHRQoL) and the actual oral health status of children.Methods: This retrospective cohort study consisted of pediatric dental chart reviews from three clinics. Demographic and dental visit data along with the child's OHRQoL utilizing the Pediatric Oral health-related Quality of Life (POQL) instrument, were collected. Associations with untreated decay, treated decay, or POQL score were tested, using Chi-square, Fisher's exact test, 2-sample t-tests, or ANOVA. Linear regression was used to evaluate the effect of statistical confounders in the relationship between untreated decay and POQL scores. Significance level was set to 0.05.Results: Two hundred ninety-seven out of 336 children had both POQL and caries data. White children and children with untreated decay had significantly more negative POQL scores. Children rating their oral health as "excellent" or "very good" and children with sealants on molars had significantly more positive POQLs. Associations between POQL scores were significant with untreated decay, but not sealants, when considering both variables in the same model. After adjusting for having sealants, POQL scores were on average 7.5 points higher (more negative) in children with untreated decay, than in children without decay (p<0.001).Conclusions: Collecting OHRQoL data allows oral health providers to easily incorporate patient perceptions in their assessment and care and would ensure that all oral health needs of the patients are being met. This is important for children, who may have difficulty expressing their concerns, particularly in clinical environments.

Evaluation of a pipeline program at strengthening applications, increasing diversity, and increasing access to care.

PURPOSE: To evaluate the outcomes of a dental pipeline program at strengthening dental school applications, growing the diversity of dental students, and increasing access to care METHODS: This program evaluation used a descriptive and quasi-experimental retrospective study design. Researchers analyzed secondary data, from a dental pipeline program, for the years 2011-2018. Descriptive statistics were used to describe short-term and intermediate outcomes and impact. Associations were tested using paired t-test, 2-sample t-test, analysis of variance, and chi-squared test RESULTS: Ninety-eight scholars completed the 10-week program. The majority of scholars were female (70%), non-Hispanic or Latino (76%), non-White (72%), and pursuing baccalaureate degrees (94%). After completing the program, the mean Dental Admission Test (DAT) Academic Average Score (AAS) increased (16.0 vs. 17.5, P < 0.01). Significant associations were revealed between post-program DAT AAS and being accepted into dental school (P = 0.02). Associations remained when stratified by gender (male P = 0.01) and ethnicity (P = 0.03). The majority of scholars (71%) applied to the host school. Over half of the scholars matriculated to dental school (55%). Twenty-nine scholars (30%) graduated from the host school. Graduates report choosing careers in private practice (38%), public health (24%), corporate dentistry (17%), and the military (3%) CONCLUSION: Dental pipeline programs are effective at strengthening dental school applications, increasing DAT AAS, growing the diversity of dental students, and increasing access to care. Dental education needs to examine barriers dental pipeline programs do not typically address, such as the high cost of applying to dental school, and identify additional ways to support underrepresented minority students entering into dentistry.

Osteocyte Wnt/ß-catenin pathway activation upon mechanical loading is altered in ovariectomized mice.

Estrogen levels decline in both sexes with age, but more dramatically in females. Activation of the Wnt/ß-catenin signaling pathway is central to the regulation of bone mass accrual and maintenance and in response to mechanical loading. Using the ovariectomized mouse model we examined the effect of estrogen loss on the osteocyte's ability to activate the Wnt/ß-catenin pathway following mechanical loading. Female TOPGAL mice underwent ovariectomy (OVX) (n = 10) or sham surgery (n = 10) at 16 weeks of age. Four weeks post-surgery, a single loading session (global strain of 2200 µÎµ for 100 cycles at 2 Hz) was performed on the right forearm with the left as a non-loaded control. Mice (n = 5) were sacrificed at 1 or 24 hr post-load. Ulnae were stained for ß-catenin activation, femurs were used for µCT and 3-pt bending/biomechanical testing, and tibiae were used for histology analysis and to determine osteocyte lacunar size using SEM and high resolution micro-XCT. A 2.2-fold increase in ß-catenin signaling activation was observed 24 hr post-load in the Sham group but did not occur in the OVX group. The OVX group versus control had significant losses (p < 0.05) in trabecular BMD (-8%), BV/TV (-35%) and thickness (-23%), along with cortical thickness (-6%) and periosteal perimeter (-4%). The OVX group had significantly higher trabecular bone osteoclast numbers (63%), OCS/BS (77%) and N.OC/BPm (94%) and a significant decrease in osteoblast number (53%), OBS/BS (37%) and N.OB/BPm (40%) compared to the sham group (p < 0.05). Cortical bone lacunar number/lacunar volume and bone biomechanical properties did not change between groups. Given that the ulna is a cortical bone loading model and the lack of changes in osteocyte lacunar number/volume in cortical bone, which would alter strains experienced by osteocytes, these data suggest the absence of estrogen resulted in intrinsic changes in the ability of the osteocyte to respond to mechanical load, rather than changes in the biomechanical and architectural properties of bone.

Age and gender related differences in load-strain response in C57Bl/6 mice.

We examined the changes in mechanical strain response of male and female mouse tibia and ulna, using axial compression tests, to assess age-related changes in tibiae and ulnae by a non-contact strain measurement technique called the digital image correlation (DIC) and the standard strain gage. A unique aspect of the study was to compare bones from the same animal to study variations in behavior with aging. This study was conducted using male and female C57Bl/6 mice at 6, 12 and 22 months of age (N=6-7 per age and sex) using three load levels. The DIC technique was able to detect a greater number of statistically significant differences in comparison to the strain gaging method. Male ulna showed significantly higher DIC strains compared to strains captured from strain gage at all three levels of load at 6 months and in the lowest load at 12 months. DIC measurements revealed that the ulna becomes stiffer with aging for both males and females, which resulted in 0.4 to 0.8 times reduced strains in the 22-month group compared to the 6 month group. Male tibia showed three-fold increased strains in the 22 months group at 11.5 N load compared to 6 months group (p<.05).