Evaluating video-based lectures on YouTube for dental education.

PURPOSE/OBJECTIVES: Multimedia presentations and online platforms are used in dental education. Though studies indicate the benefits of video-based lectures (VBLs), data regarding user reception and optimal video features in dental education are limited, particularly on Web 2.0 platforms like YouTube. Given increasing technology integration and remote learning, dental educators need evidence to guide implementation of YouTube videos as a freely available resource. The purpose of this study is to determine video metrics, viewership and format efficacy for dental education videos. METHODS: First, a cross-sectional survey was conducted of viewers (N = 683) of the Mental Dental educational videos on YouTube. Analytics were evaluated for 677 200 viewers to assess audience demographics, retention and optimal video length. Second, a randomized crossover study was conducted of dental students (N = 101) who watched VBLs in either slideshow or pencast formats and were tested on content learning to compare format efficacy. RESULTS: Most viewers of Mental Dental videos were dental students (44.2%) and professionals (37.8%) who would likely recommend the platform to a friend or colleague (Net Promoter Score = 82.1). Audience retention declined steadily at 1.34% per minute, independent of video length. Quiz performance did not differ between slideshow and pencast videos, with students having a slight preference for slideshows (P = 0.049). CONCLUSIONS: Dental students and professionals use VBLs and are likely to recommend them to friends and colleagues. There is no optimal video length to maximize audience retention and lecture format (slideshow vs. pencast) does not significantly impact content learning. Results can guide implementation of VBLs in dental curricula.

Patient and Caregiver Perceptions of Animal Assisted Activity in Orthodontics.

Dental anxiety affects up to 21% of children and 80% of adults and is associated with lifelong dental avoidance. Animal assisted activity (AAA) is widely used to reduce anxiety and pain in medical settings and has promise in dentistry. The primary objective of this study was to evaluate caregiver and patient perceptions of canine AAA in orthodontics. A cross-sectional survey consisting of pre-tested and validated questions was conducted (n = 800) including orthodontic patients (n = 352 minors, n = 204 adults) and parents/caregivers (n = 244) attending university orthodontic clinics. In this study, AAA and dog therapy were not used or tested for dental anxiety management. More than a third of orthodontic patients (37%) had moderate or greater anxiety related to care. Participants believed that therapy animals would make dental experiences more enjoyable (75%) and reduce anxiety (82%). There was little to no concern expressed regarding cleanliness (83%), allergies (81%), and safety (89%) with a therapy animal in dental settings. Almost half of the participants would preferentially select an orthodontic office offering AAA. In light of the COVID-19 pandemic, we assessed whether perceptions of AAA changed before and after the shutdown of dental offices, with no significant differences. Across patients and caregivers, the responses support the use of AAA in orthodontic settings with minimal concerns.

Effects of the COVID-19 pandemic on dentists' workforce confidence and workflow.

BACKGROUND: The COVID-19 pandemic has affected the US economy and workforce, including marked effects on small businesses. Researchers have evaluated workers' views of financial confidence and advancement, but there has been limited focus on the dental industry. METHODS: To extend investigations to dentistry, the authors used published scales and pretested questions to determine workforce confidence and workflow changes among dentists. Data were evaluated using descriptive and bivariate statistics. In the wake of the pandemic, surveys were distributed to the memberships of the American Dental Association and American Association of Orthodontists (n = 656). RESULTS: Dentists' top concern was increased cost of providing treatment (57.4%; 95% CI, 53.5% to 61.3%), associated with widely adopted workflow changes including reduced patient volumes (66.0%; 95% CI, 62.4% to 69.6%) and increased safety protocols and equipment (health screening: 75.5%; 95% CI, 72.2% to 78.8%; KN/N95 respirators: 76.7%; 95% CI, 73.5% to 80.0%). However, most respondents did not expect their personal or practice finances to be negatively affected after the pandemic, as only 18.5% (95% CI, 15.4% to 21.7%) predicted their practice's gross revenue would decrease. CONCLUSIONS: Dentists were optimistic in the wake of vaccinations and lifting restrictions. Most expected their finances and practice performance to remain the same or grow in the short term and expected long-term improvements postpandemic. PRACTICAL IMPLICATIONS: Results suggest that despite shutdowns and workflow changes, dentists have rebounded financially and anticipate future growth.

Optical properties of a novel glass-ceramic restorative material.

OBJECTIVE: To examine the optical properties of a dental restorative material manufactured from lithium aluminosilicate ceramic and reinforced with lithium disilicate. Translucency and the optical effects of various supporting materials on color were the primary focus. METHODS: Five 10 × 10 mm samples were prepared in thicknesses of 0.5, 1.0, 1.5, and 2.0 mm of both high translucency (HT) and low translucency (LT) versions of the material in shade A3. A spectrophotometer was used to measure the illuminance of the samples with black and white backings in order to calculate contrast ratio (CR) and relative translucency parameter (RTP). A baseline relationship between translucency and material thickness was examined and the effects of composite, titanium, and zirconia abutments on color change were studied. RESULTS: No significant findings were identified for RTP or CR between the HT and LT material, regardless of the material thickness (p = 0.39, p = 0.14, respectively). Regardless of material thickness (HT vs. LT), translucencies (RTP and CR) were significantly different with composite, titanium, and zirconia backings compared to baseline values (p < 0.0001). Titanium had the most significant decrease in translucency compared to composite and zirconia. There was no difference in ΔE00 between the HT and LT materials (p > 0.05) regardless of the backing. Titanium had the most significant effect on color of both materials followed by composite then zirconia (p < 0.0001). CONCLUSIONS: There is not a clinically significant difference in translucency between the high translucency and low translucency materials. Only zirconia supporting structures produced changes in color that are clinically acceptable. CLINICAL SIGNIFICANCE: Understanding the optical properties of glass-ceramic restorative materials aids providers in selecting appropriate materials for optimum esthetic outcomes. The lithium-aluminosilicate reinforced with lithium disilicate material does a poor job masking supporting structures and resisting color change.

Influence of BMI percentile on craniofacial morphology and development in children and adolescents.

BACKGROUND: The prevalence of childhood and adolescent obesity is increasing worldwide. Reports suggest that elevated body mass index (BMI) is associated with larger craniofacial dimensions and advanced dental and skeletal development. Such an association is important for timing orthodontic treatment relative to pubertal growth and dental eruption. MATERIALS AND METHODS: To evaluate associations between BMI, craniofacial morphology, dental age, and cervical vertebrae maturation staging (CVMS), 400 participants were consecutively selected (8-15 years, n = 200 overweight and obese BMI >85%, 200 normal weight) from the University of North Carolina database. Records were analysed for cephalometric measures, Demirjian index values, and CVMS. Bivariate statistics and linear regression analysis evaluated whether CVMS, dental age, and cephalometric dimensions varied with BMI. RESULTS: Overweight/obese children and adolescents had a proportionally larger bimaxillary prognathic skeletal pattern compared to those of normal weight. These cephalometric measurements [articulare-gnathion (Ar-Gn), condylion-anterior nasal spine (Co-ANS), sella-gonion (S-Go), nasion-menton (N-Me), anterior nasal spine-menton (ANS-Me), sella-nasion-A point (SNA), sella-nasion-B point (SNB), and sella-nasion-pogonion (SNPg)] were significantly different [statistically (P < 0.05) and clinically (>2 mm or >2 degrees)] between the two study groups, with a linear relationship between BMI percentile and craniofacial dimension. The overweight/obese BMI group had a mean dental age 1.4 years advanced relative to the normal weight group (P < 0.05), with an advancement of nearly one CVM stage between the ages of 12 and 14 (P < 0.05). LIMITATIONS: The study is retrospective. CONCLUSIONS: Obese/overweight children and adolescents have proportionally larger antero-posterior and vertical dimensions and are more likely to experience advanced dental and skeletal maturation. Obese/overweight subjects may enter their growth spurt at a younger age and have earlier eruption of teeth, affecting treatment timing. BMI percentile should be a consideration for orthodontic treatment in growing patients.

"I don't think the problem's the student I think it's us": Engaging faculty in curriculum innovation.

PURPOSE: The need to innovate predoctoral dental education is well established; however, there are few recent reports to guide substantial curriculum transformation. The purpose of this study was to describe faculty perspectives on their vision of future graduates, curriculum needs, and potential barriers to a successful redesign. This information would be used to inform strategic planning for the predoctoral curriculum transformation. METHODS: Eighty full-time faculty from the University of North Carolina Adams School of Dentistry participated in 60-minute focus groups in March 2018. Focus group questions were developed to elicit perceptions about the current curriculum, what the dental graduate should know in 2040, and what is needed to engage faculty in curriculum change. Transcripts of the focus group sessions were analyzed by a third-party research group using qualitative thematic analysis to identify pertinent themes shared by participants. RESULTS: Faculty identified that developing clinical skill that engages multiple specialties, student time to engage in advocacy activities, and opportunities to integrate biomedical, clinical, and behavioral sciences as critical features of the curriculum. They believed the 2040 graduate should be able to critically evaluate literature, exhibit strong leadership skills, and adapt to the changing healthcare environment. To better engage faculty in curriculum change, there needs to be dedicated time, sufficient resources, a clear plan, and greater collaboration across the school. CONCLUSION: When embarking on curriculum transformation, engagement with faculty is a critical component of the change process. Focus groups can be used as a technique to better understand faculty perspectives about curricular needs and the overall vision.

Developing a curriculum blueprint and taxonomy: Process, progress, and pivots.

Curriculum transformations represent opportunities to innovate; however, there are few examples to inform this process. In 2018, the University of North Carolina at Chapel Hill (UNC) Adams School of Dentistry began to transform the predoctoral curriculum to improve content integration, enhance team-based experiences, and develop leaders. Part of this experience has been crafting a conceptual curriculum guide or "blueprint" that outlines a vision for the design process and ensures the transformation achieves its goals. We describe how we created the UNC Blueprint for our revised curriculum, which defines who our graduates are, what they know, and what they can do. This approach has led us to develop a mapping taxonomy to ensure the student outcomes are appropriately aligned with content, instruction, and assessment throughout the curriculum. Last, we encourage others to be agile in their approach, create a common language among their teams, and frequently engage faculty to facilitate the process.

Nonsurgical treatment of an adult with a skeletal Class III malocclusion combined with a functional anterior shift, severely overclosed vertical dimension, and a reverse smile.

This case report illustrates the successful nonsurgical treatment of an adult with a skeletal Class III malocclusion exacerbated by a functional anterior shift that resulted in a severe overclosure of the mandible and a reverse smile line. To maximize the soft tissue and smile esthetics while idealizing the occlusion, active clockwise rotation of the mandible was induced along with mandibular molar uprighting and sequential leveling. In the maxilla, full arch distalization was achieved after second molar extraction. The treatment provided a satisfying esthetic and functional outcome and has remained stable.

Traumatic dental injuries in preschool-age children: Prevalence and risk factors.

This study examined the prevalence, socio-demographic correlates, and clinical predictors of traumatic dental injuries (TDIs) in the primary dentition among a community-based sample of preschool-age children. The sample comprised 1,546 preschool-age children (mean age 49 [range: 24-71] months) in North Carolina public preschools, enrolled in a population-based investigation among young children and their parents in North Carolina. Information on socio-demographic, extraoral, and intraoral characteristics was collected and analyzed with bivariate and multivariate methods, including logistic regression modeling and marginal effects estimation. The prevalence of dental trauma was 47% and 8% of TDI cases were "severe" (pulp exposure, tooth displacement, discolored or necrotic tooth, or tooth loss). In bivariate analyses, overjet and lip incompetence were significantly associated with TDI. Overjet remained positively associated with severe trauma in multivariate analysis, OR = 1.4, 95% confidence interval (CI) [1.2, 1.6], corresponding to an absolute 1.3%, 95% CI [0.7, 1.8], increase in the likelihood of severe trauma, per millimeter of overjet. Children with increased overjet (>3 mm) were 3.8, 95% CI [2.0, 7.4], times as likely to have experienced severe TDI compared with those with ≤3 mm. Overjet is a strong risk factor for TDIs in the primary dentition. Incorporating and operationalizing this information may help TDI prevention and related anticipatory guidance for families of preschool-age children.

Comparison of condylar position in orthognathic surgery cases treated with virtual surgical planning vs. conventional model planning.

OBJECTIVES: To assess the effect of virtual surgical planning (VSP) on the accuracy of condylar seating in surgical cases involving Bilateral Sagittal Split Osteotomy (BSSO). An additional aim was to quantify differences between actual surgical outcome and planned virtual outcome. SETTING AND SAMPLE POPULATION: A private practice in Charlotte North Carolina. Twenty-five consecutively operated subjects prepared with VSP and twenty consecutively subjects operated with conventional surgery planning were enrolled. MATERIAL AND METHODS: Cone beam computed tomography (CBCT) scans were obtained before surgery (T1) and post-surgery after splint removal (T2). The T1 and T2 CBCTs were superimposed on the anterior cranial base using voxel-based registration. Three dimensional (3D) models were built and oriented to a 3D Frankfurt horizontal. Displacement of corresponding condylar landmarks was measured. RESULTS: No significant difference was found between the VSP and conventional group in the magnitude of translation or rotation of the condyles following surgery. VSP surgical outcomes differed significantly from predicted positions at all landmarks. Virtual surgical planning does not prevent changes to condylar position as a result of surgery. Actual surgical results differed significantly from VSP-predicted outcomes. CONCLUSIONS: Virtual surgical planning did not reduce the changes to condylar position and angulation that resulted from conventionally planned orthognathic surgery.

Call for ACTion: Transforming Dental Education at the University of North Carolina at Chapel Hill.

The University of North Carolina at Chapel Hill Adams School of Dentistry is developing a transformative curriculum that prepares students to enter contemporary practice. The Advocate, Clinician, and Thinker (ACT) framework will provide the basis for developing a resilient workforce capable of meeting emerging health care needs over the next 40 years.

Diagnostic accuracy of intraoral photographic orthodontic records.

OBJECTIVE: The aims of this study were (1) to investigate how relevant intraoral photographs are to contemporary orthodontic diagnosis and (2) to assess orthodontists' ability to accurately diagnose angle classification and dental midlines using standardized intraoral photographs. METHODS: Study participants were orthodontists who completed a survey regarding photography protocols and their use of intraoral photographs for diagnosis. Each participant was randomized to complete 1 visual diagnostic task regarding either angle classification or midlines. Accuracy was compared across groups and camera angulations. RESULTS: In all, 80% of 192 respondents reported using photographs and clinic notes to plan orthodontic treatment; 50% also included dental casts. For the angle task, accuracy judging molar and canine classification was 79.9% and 51.3%, respectively with ideal standardized photographs. As camera angulation deviated, accuracy decreased significantly (P < 0.0001). For the midline task, accuracy judging the direction of deviation decreased with a small camera angulation change yet increased with a large change (P < 0.001). CONCLUSIONS: When using ideal intraoral photographs alone to diagnose angle classification and midline relationships, accuracy is not likely to be greater than 80%. As camera angulation becomes less ideal, by 15 degrees when judging angle classification or 4 degrees when judging midlines, accuracy is likely to significantly decrease. CLINICAL SIGNIFICANCE: For the clinician who wants to have the most accurate and complete records, our results suggest that intra-oral photos alone may not be adequate when it comes to judging occlusal relationships such as angle classification and esthetic parameters like midlines. When using ideal intraoral photographs to diagnose angle classification and midline relationships, accuracy is not likely to be greater than 80%. As camera angulation becomes less ideal, by as little as 15 degrees when judging angle classification or 4 degrees when judging midlines, accuracy is likely to decrease significantly. Understanding these limitations will allow clinicians to improve both their clinical photography technique and their diagnostic skills.

Three-dimensional mandibular regional superimposition in growing patients.

INTRODUCTION: The aims of this study were to identify stable mandibular structures in 3 dimensions in growing patients using a regional implant technique and to test the reproducibility of mandibular regional superimposition in 3 dimensions using the regions identified. METHODS: Three-dimensional voxel-based regional mandibular registrations were performed on bone plates, and screws were placed in the anterior chin and symphysis regions of 20 growing patients (mean age, 12.1 ± 1.3 years). Three-dimensional models of the resulting superimpositions were built for the chin, symphysis, and third molar crypts. Absolute mean errors were calculated for each region to evaluate stability. Longitudinal cone-beam computed tomography scans were obtained of 25 patients (mean age, 12.7 ± 1.4 years) with different skeletal malocclusions (20 Class II, 5 Class III). To evaluate reliability of mandibular registrations using the chin and symphysis regions, voxel-based superimpositions were performed independently by 2 observers. The resulting superimpositions between the 2 examiners were overlaid, and the mean difference along the entire surface of the mandible was calculated. RESULTS: The chin and symphysis regions showed high levels of precision (chin absolute mean error, 0.37 ± 0.16 mm; symphysis absolute mean error, 0.4 ± 0.15 mm). The third molar region had a high registration error (absolute mean error, 1.94 ± 0.06 mm). The voxel-based registrations using the chin and symphysis were reliable and reproducible between examiners (absolute mean error, 0.12 ± 1.1 mm). Intraclass correlation coefficient results showed a high degree of agreement between examiners. CONCLUSIONS: The chin and symphysis regions are stable areas for 3-dimensional mandibular regional superimpositions.

Self-Directed Digital Learning: When Do Dental Students Study?

The Growth and Development (G&D) curriculum at the University of North Carolina at Chapel Hill School of Dentistry uses self-directed web-based learning modules in the place of lectures and includes scheduled self-study times during the 8 am-5 pm school hours. The aim of this study was to use direct observation to evaluate dental students' access patterns with the self-directed, web-based learning modules in relation to planned self-study time allocated across the curriculum, proximity to course examinations, and course performance. Module access for all 80 students in the DDS Class of 2014 was recorded for date and time across the four G&D courses. Module access data were used to determine likelihood of usage during scheduled time and frequency of usage in three timeframes: >7, 3 to 7, and 0 to 2 days before the final exam. The results showed a statistically significant difference in the likelihood of module access during scheduled time across the curriculum (p<0.0001). Among the students, 64% accessed modules at least once during scheduled time in G&D1, but only 10%, 19%, and 18% in G&D2, G&D3, and G&D4, respectively. For all courses, the proportion of module accesses was significantly higher 0-2 days before an exam compared to the other two timeframes. Module access also differed significantly within each timeframe across all four courses (p<0.001). There was no association between module access and course performance. In this non-traditional, non-lecture, self-directed curriculum, students rarely accessed learning modules during syllabus-budgeted self-study time and accessed modules more frequently as course exams approached.

Extraction frequencies at a university orthodontic clinic in the 21st century: Demographic and diagnostic factors affecting the likelihood of extraction.

INTRODUCTION: The aims of this study were to report contemporary orthodontic extraction frequencies at a university center and to investigate what patient-related factors might influence the likelihood of extraction. METHODS: The records of 2184 consecutive patients treated at the University of North Carolina from 2000 to 2011 were analyzed. Year-by-year rates for overall orthodontic extractions and for extraction of 4 first premolars were calculated. Logistic regression, adjusting for all recorded patient risk factors for extraction, was used to examine both the changes in extraction frequencies over time and the influence of individual patient factors on the odds of extraction. RESULTS: Small linear decreases in orthodontic extraction frequency overall (OR, 0.91; 95% CI, 0.88-0.95) and in extraction of 4 first premolars (OR, 0.95; 95% CI, 0.90-0.99) were seen. The overall extraction rate was 37.4% in 2000, and it fell just below 25% from 2006 onward. Four first premolar extraction rates ranged from 8.9% to 16.5%. Extractions were significantly more likely as crowding and overjet increased (OR, 1.2; 95% CI, 1.14-1.25; OR, 1.1; 95% CI. 1.07-1.19), as overbite decreased (OR, 0.8; 95% CI, 0.77-0.89), with Class II dental or skeletal relationships (OR, 1.5; 95% CI, 1.12- 2.05; OR, 1.4; 95% CI, 1.04-1.85), and for nonwhite patients (OR, 3.0; 95% CI, 2.2-4.06 for other races; OR, 4.1; 95% CI, 3.03-5.66 for African Americans). CONCLUSIONS: Extractions were just as likely to be associated with Class II dental and skeletal problems and with open-bite problems as with crowding alone.

Enhanced Facial Symmetry Assessment in Orthodontists.

Assessing facial symmetry is an evolutionarily important process, which suggests that individual differences in this ability should exist. As existing data are inconclusive, the current study explored whether a group trained in facial symmetry assessment, orthodontists, possessed enhanced abilities. Symmetry assessment was measured using face and non-face stimuli among orthodontic residents and two control groups: university participants with no symmetry training and airport security luggage screeners, a group previously shown to possess expert visual search skills unrelated to facial symmetry. Orthodontic residents were more accurate at assessing symmetry in both upright and inverted faces compared to both control groups, but not for non-face stimuli. These differences are not likely due to motivational biases or a speed-accuracy tradeoff-orthodontic residents were slower than the university participants but not the security screeners. Understanding such individual differences in facial symmetry assessment may inform the perception of facial attractiveness.

Face symmetry assessment abilities: Clinical implications for diagnosing asymmetry.

INTRODUCTION: An accurate assessment of face symmetry is necessary for the development of a dentofacial diagnosis in orthodontics, and an understanding of individual differences in perception of face symmetry between patients and providers is needed to facilitate successful treatment. METHODS: Orthodontists, general dentists, and control participants completed a series of tasks to assess symmetry. Judgments were made on pairs of upright faces (similar to the longitudinal assessment of photographic patient records), inverted faces, and dot patterns. Participants completed questionnaires regarding clinical practice, education level, and self-confidence ratings for symmetry assessment abilities. RESULTS: Orthodontists showed expertise compared with controls (P <0.001), whereas dentists showed no advantage over controls. Orthodontists performed better than dentists, however, in only the most difficult face symmetry judgments (P = 0.006). For both orthodontists and dentists, accuracy increased significantly when assessing symmetry in upright vs inverted faces (t = 3.7, P = 0.001; t = 2.7, P = 0.02, respectively). CONCLUSIONS: Orthodontists showed expertise in assessing face symmetry compared with both laypersons and general dentists, and they were more accurate when judging upright than inverted faces. When using accurate longitudinal photographic records to assess changing face symmetry, orthodontists are likely to be incorrect in less than 15% of cases, suggesting that assistance from some additional technology is infrequently needed for diagnosis.

Changes in the pattern of patients receiving surgical-orthodontic treatment.

INTRODUCTION: The characteristics of patients who seek and accept orthognathic surgery appear to be changing over time but have not been well documented in the 21st century. METHODS: Records for patients who had orthognathic surgery at the University of North Carolina from 1996 to 2000 and from 2006 to 2010 were reviewed to collect data for changes in the prevalence of patients with mandibular deficiency (Class II), maxillary deficiency or mandibular prognathism (Class III), long face, and asymmetry problems. The changes were compared with those in previous time periods and at other locations. RESULTS: Between 1996 and 2000 and between 2006 and 2010, the percentage of Class III patients increased from 35% to 54%, and the percentage of Class II patients decreased from 59% to 41%, while the percentages for long face and asymmetry showed little change. The decrease in Class II patients was accentuation of a long-term trend; the increase in Class III patients occurred only after the turn of the century. CONCLUSIONS: A similar but less-marked change has been noted at some but not all other locations in the United States. It appears to be related primarily to an increase in the numbers of African Americans, Native Americans, Hispanics, and Asians who now are seeking surgical treatment, but it also has been affected by changes in where orthognathic surgery is performed, decisions by third-party payers (insurance and Medicaid) about coverage for treatment, and the availability of nonsurgical orthodontic treatment options for Class II patients.

Effectiveness of web-based teaching modules: test-enhanced learning in dental education.

The purpose of our study was to evaluate the effectiveness of self-tests as a component of web-based self-instruction in predoctoral orthodontics and pediatric dentistry. To this end, the usage patterns of online teaching modules and self-tests by students enrolled in three courses at the University of North Carolina at Chapel Hill School of Dentistry were monitored and correlated to final exam grade and course average. We recorded the frequency of access to thirty relevant teaching modules and twenty-nine relevant self-tests for 157 second- and third-year D.D.S. students during the course of our data collection. There was a statistically significant positive correlation between frequency of accessing self-tests and course performance in one course that was totally based on self-instruction with seminars and multiple-choice examination (Level IV): Spearman correlation between frequency of self-test access and final exam grade, rho=0.23, p=0.044; correlation between frequency of self-test access and course average: rho=0.39, p=0.0004. In the other two courses we monitored, which included content beyond self-instruction with self-tests, the correlations were positive but not statistically significant. The students' use of online learning resources varied significantly from one course (Level I) to the next (Level II): Wilcoxon matched pairs signed-rank tests, S=-515.5, p=.0057 and S=1086, p<0.0001. The data from this study suggest that increased use of web-based self-tests may be correlated with more effective learning in predoctoral dental education by virtue of the testing effect and that dental students' usage of resources for learning changes significantly over the course of their education.