Antibacterial Activity and Shear Bond Strength of Orthodontic Adhesive Containing Various Sizes of Chitosan Nanoparticles: An In Vitro Study.

INTRODUCTION: White spot lesions are common after orthodontic treatment. Chitosan nanoparticles (CS-NPs) have emerged as promising antibacterial agents that inhibit the growth of Streptococcus mutans. The aim of the study was to investigate the nano-effect of adhesives containing CS-NPs on S. mutans and their effects on shear bond strength. MATERIALS AND METHODS: The inhibitory effects of two sizes of CS-NPs were assessed using the disc agar diffusion method. Four wells were created in the petri dishes, and each was inoculated with broth (negative control), chlorhexidine (positive control), CS-NPs (20 nm), or CS-NPs (131 nm). An Instron machine was used to evaluate shear bond strength by allocating 24 teeth into three groups, and all measurements were recorded in megapascals. Caries progression was assessed using the International Caries Detection and Assessment System and surface profilometry. Statistical analysis was performed using IBM SPSS Statistics for Windows, Version 27.0 (Released 2020; IBM Corp., Armonk, New York, United States) for a one-way ANOVA followed by Tukey's multiple comparison test. RESULTS: Disc agar diffusion showed a reduction in S. mutans in the CS-NP group compared to the control (p < 0.001), with no statistical significance between the sizes of 20 and 131 nm (p = 0.95). Regarding shear bond strength, no differences were recorded when adhesive-containing CS-NPs and the control were compared (p = 0.44). Additionally, no differences were found within the CS-NP groups (p = 0.91). Caries assessments showed excellent agreement, as indicated by a weighted kappa. Profilometry readings showed higher surface roughness in the control than in the CS-NP groups (p < 0.001), with no statistically significant difference between the CS-NP groups (p = 0.72). CONCLUSION: CS-NPs of both sizes tested had similar antibacterial effects. In addition, the incorporation of CS-NPs did not affect shear bond strength.

Identification of Salivary Metabolic Signatures Associated with Primary Sjögren's Disease.

Sjögren's disease (SjD) is the second most prevalent autoimmune disorder that involves chronic inflammation of exocrine glands. Correct diagnosis of primary SjD (pSjD) can span over many years since disease symptoms manifest only in advanced stages of salivary and lachrymal glandular destruction, and consensus diagnostic methods have critical sensitivity and selectivity limitations. Using nuclear magnetic resonance (NMR) spectroscopy, we determined the composition of metabolites in unstimulated saliva samples from 30 pSjD subjects and 30 participants who do not have Sjögren's disease (non-Sjögren's control group, NS-C). Thirty-four metabolites were quantified in each sample, and analysis was conducted on both non-normalized (concentration) and normalized metabolomics data from all study participants (ages 23-78) and on an age-restricted subset of the data (ages 30-70) while applying false discovery rate correction in determining data significance. The normalized data of saliva samples from all study participants, and of the age-restricted subset, indicated significant increases in the levels of glucose, glycerol, taurine, and lactate, as well as significant decreases in the levels of 5-aminopentanoate, acetate, butyrate and propionate, in subjects with pSjD compared to subjects in the NS-C group. Additionally, a significant increase in choline was found only in the age-restricted subset, and a significant decrease in fucose was found only in the whole study population in normalized data of saliva samples from the pSjD group compared to the NS-C group. Metabolite concentration data of saliva samples from all study participants, but not from the age-restricted subset, indicated significant increases in the levels of glucose, glycerol, taurine, and lactate in subjects with pSjD compared to controls. The study showed that NMR metabolomics can be implemented in defining salivary metabolic signatures that are associated with disease status, and can contribute to differential analysis between subjects with pSjD and those who are not affected with this disease, in the clinic.

External Cervical Resorption: Relationships between Classification, Treatment, and 1-Year Outcome with Evaluation of the Heithersay and Patel Classification Systems.

INTRODUCTION: The purpose of this study was to identify possible associations between classification, treatment, and 1-year outcome of external cervical resorption (ECR) lesions using the Heithersay and Patel systems. Performance of the Patel 3-dimensional classification system was also evaluated. METHODS: A chart review identified 142 cases of ECR over a 12-year period. Information regarding demographics, predisposing factors, lesion classification, treatment, and outcomes were collected and analyzed. Inter- and intraobserver reliability analyses were conducted for both classification systems. RESULTS: There were 72 cases with at least 1 year of follow up; 70% of these cases survived. Treatment recommendations were correlated with both Heithersay and Patel classification. There were no correlations found between 1-year outcome and either classification or treatment done. The weighted reliability analysis showed substantial agreement in both classification systems for both inter- and intraobserver agreement. There was a significant association between the 2 systems; however, the Heithersay system tended to underestimate the apical extent of the lesion. CONCLUSIONS: Periodic review of ECR lesions presents as a viable treatment option, at least for 1 year after diagnosis. The Patel 3-dimensional classification system is at least as effective as the Heithersay system and should be used in future ECR prognosis studies. Further long-term outcome assessments are still needed.

Effects of proinflammatory cytokines on lacrimal gland myoepithelial cells contraction.

In the lacrimal gland, myoepithelial cells (MEC) express muscle contractile proteins such as alpha smooth muscle actin (SMA) and calponin and therefore can contract to help expel lacrimal fluid. In a previous study, we demonstrated that lacrimal gland MEC express the oxytocin receptor (OXTR) and they contract under oxytocin (OXT) stimulation. Using NOD and MRL/lpr mice (animal models of Sjogren's syndrome), we reported a decrease in SMA and calponin protein levels plus a decline in acini contraction after stimulation with OXT. It is known that proinflammatory cytokines, such as interleukin-1ß (IL-1ß), tumor necrosis factor alpha (TNF-α) or interferon gamma (IFN-γ), can affect OXTR expression and signaling capacity and inhibit MEC contraction. The aim of the current study was to investigate if proinflammatory cytokines are implicated in the loss of MEC contractile ability. Thus, lacrimal gland MEC from a SMA-GFP transgenic mouse were treated with IL-1ß (10 ng/ml) for a total of 7 days. At days 0, 2, 4 and 7, GFP intensity, cell size/area, contractile proteins amounts and MEC contraction were assessed. At day 0, control and treated cells showed no differences in GFP intensity and cell size. GFP intensity started to decrease in treated MEC at day 2 (20%; p=0.02), continuing after day 4 (25%; p=0.007) and 7 (30%; p=0.0001). Mean cell area was also reduced at day 2 (34%; p=0.0005), and after 4 (51%; p<0.0001) and 7 days (30%; p=0.0015). The contraction assay at day 2 showed a 70% decrease of contraction in treated MEC (p<0.0001), 73% (p<0.0001) at day 4 and 82% (p=0.0015) at day 7 when compared to control. Levels of contractile proteins were measured on day 7 showing a decrease in SMA and calponin amount in treated MEC compared with the control group (around 30%; p=0.0016 and p=0.0206; respectively). Similar results were observed when TNF-α and IFN-γ were added along with IL-1ß. Taken together the present data and those from our previous studies with Sjogren's syndrome mouse models, they strongly suggest that proinflammatory cytokines affect lacrimal gland MEC contractile ability that may account for the reduced tear secretion associated with Sjogren's syndrome dry eye disease.

Oral health conditions and correlates: a National Oral Health Survey of Rwanda.

Background: Dental diseases are chronic, lifelong and preventable yet affect over half the world's population. Personal oral hygiene practices and socio-economic factors contribute to oral health outcomes affecting oral health quality of life. Integrating basic oral care within community level health systems increases accessibility and availability of oral health resources.Objective: National Oral Health Survey of Rwanda (NOHSR) data were investigated for associations of socio-demographic characteristics, personal oral hygiene practices, oral health outcomes, and oral health quality of life indicators.Methods: Data were analyzed and descriptive statistics calculated. Multivariable logistic regression models were developed to assess associations between untreated caries, calculus, and pain with various independent variables (demographics and personal oral hygiene practices). Additional logistic regression models examined associations between quality of life indicators and the aforementioned independent variables as well as untreated caries and pain.Results: Those who did not use a toothbrush (62.7%), or toothpaste (70.0%), and cleaned their teeth less than once per day (55.3%) had a higher prevalence of untreated caries. Approximately one-third of those in rural areas cleaned their teeth once per day or more compared to two-thirds of those in urban areas (35.4% vs. 71.2%). Those cleaning their teeth less than once daily were estimated to have 56.0% higher odds of caries than those who cleaned their teeth once a day or more (OR = 1.56, [95% CI 1.25-1.95]). Those with secondary education or higher and those with skilled jobs demonstrated more frequent teeth cleaning and higher toothbrush and toothpaste use. Quality-of-life indicators varied significantly with untreated caries and pain.Conclusion: Socio-economic, individual, and workforce characteristics are important considerations when assessing oral health outcomes. This study investigated social demographic disparities in relation to oral health related behaviors and outcomes. This information can help guide oral health care programming in Rwanda.

Conducting Surveys in Dental Education Research: Guidelines and Reminders.

The use of surveys is popular in dental education research. However, designing and conducting a survey can have many pitfalls. This article aims to prepare a new researcher or one with little experience to undertake survey research. It covers points such as survey design (including question construction), pilot testing for validity and reliability, sampling strategy, methods to increase response rates, logistical considerations, and items to include when writing the manuscript. Careful consideration of a survey from beginning to end can help one design and conduct a successful study that meets its research aims and adds valuable evidence to the literature.

The effectiveness of acupuncture in the management of persistent regional myofascial head and neck pain: A systematic review and meta-analysis.

Persistent head and neck myofascial pain is among the most frequently reported pain complaints featuring major variability in treatment approaches and perception of improvement. Acupuncture is one of the least invasive complimentary modalities that can optimize conventional treatment. The aim of this review was to determine the evidence for the effectiveness of acupuncture in the management of localized persistent myofascial head and neck pain. Only randomized controlled clinical trials (RCTs) were included. The search was conducted in PubMed, Ovid Medline, Embase, Google Scholar, and Cochrane Library in addition to manual search. The main outcome measure was the comparison of the mean pain intensity score on VAS between acupuncture and sham-needling/no intervention groups. Safety data and adherence rate were also investigated. Six RCTs were identified with variable risk of bias. All included studies reported reduction in VAS pain intensity scores in the groups receiving acupuncture when compared to sham needling/no intervention. Meta-analysis, using a weighted mean difference as the effect estimate, included only 4 RCTs, revealed a 19.04 point difference in pain intensity between acupuncture and sham-needling/no intervention (95 %CI: -29.13 to -8.95). High levels of safety were demonstrated by the low rates of side effects/withdrawal. Inconsistency in reporting of outcomes was a major limitation. In conclusion, moderate-quality evidence suggests that acupuncture may be an effective and safe method in relieving persistent head and neck myofascial pain. Optimizing study designs and standardizing outcome measures are needed for future RCTs.

Early Clinical Exposure in U.S. Dental Schools and Correlation with Earlier Competencies Evaluation.

Early clinical exposure (ECE), defined as any interaction with patients prior to the portion of the curriculum when den- tal students spend most of their time at school as a primary provider, is a growing trend in curriculum reform across U.S. dental schools in the 21st century. The aims of this study were to characterize the types of ECE implementation in U.S. dental schools and determine if ECE correlated with earlier clinical competency assessments. In September 2018, the academic deans of all 66 U.S. dental schools were invited to respond to an eight-item electronic survey about ECE at their schools. Representatives of 40 schools submitted complete responses, for a response rate of 60.6%. Among the respondents, 85% reported their schools started their principal clinical experience (PCE), the portion of the curriculum when students spend most of their time as the primary provider for patients, during the last quarter of Year 2 or the first quarter of Year 3. Respondents at all 40 schools reported offering some form of ECE as part of the formal curriculum, with shadowing and performing dental prophylaxis the most commonly of- fered types. No statistically significant associations were found between specific types of ECE and related Commission on Dental Accreditation (CODA) clinical standards for both formative and summative assessments. Although U.S. dental schools have been incorporating more ECE into their curricula over the past decade, these findings suggest that it has not led to earlier clinical competency assessments.

Renal outcomes of neonates with early presentation of posterior urethral valves: a 10-year single center experience.

OBJECTIVE: Evaluate renal outcomes and early predictive factors in infants with congenital posterior urethral valves who required catheter or surgical urinary tract decompression within the first 7 days of life. STUDY DESIGN: A 10-year retrospective study at a single hospital. Primary outcomes were estimated glomerular filtration rate (eGFR) and development of end stage renal disease (ESRD). RESULTS: Of 35 infants, 50% developed eGFR <90 mL/min/1.73 m2 and 15% progressed to ESRD. Nadir creatinine, need for invasive ventilation in the newborn period, and need for surgical diversion after catheter diversion were associated with worse outcomes. 50% of infants requiring invasive ventilation as neonates developed eGFR <60 mL/min/1.73 m2 in childhood. CONCLUSIONS: Half of infants with early presentation and intervention developed significant renal insufficiency in childhood, similar to children with later presentation or who had fetal intervention. Invasive ventilation in the newborn period and need for surgical urinary diversion are associated with worse outcomes.

Effect of time in function on the predictability of short dental implants (≤6 mm): A meta-analysis.

PURPOSE: To analyse randomised controlled clinical trials (RCTs) and prospective cohort studies reporting on the survival and failure rates of functionally loaded short implants (SI) based on the actual length of time in function. MATERIALS AND METHODS: This meta-analysis was conducted according to PRISMA guidelines for systematic reviews. Electronic and manual searches were conducted to identify RCTs and prospective cohort studies reporting survival and complication rates of short dental implants (≤6 mm) based on the time in function. Secondary outcomes included the location (maxilla or mandible), type of restoration (single crown [SC] versus fixed dental prosthesis [FDP]) and marginal bone loss (MBL). RESULTS: A total of 20 studies (11 RCTs and 9 prospective) fulfilled the inclusion criteria and featured a total of 1238 SI placed in 747 patients. The overall (early and late) mean percentage of short implant failure was 4%. SI with up to 1-year follow-up presented failure rate of 2%, while SI followed up for >3 years showed a failure rate of 10%. SI restored with SC presented a late failure rate of 4% while SI restored with FPD 2%. The late failure rate did not differ in terms of location (maxilla or mandible) both with 3%. CONCLUSION: Short implants in function for more than 3 years presented higher failure rates compared to SI in function for <3 years. Splinting crowns supported by SIs in the posterior area should be considered. However, SI is a valid option for selected cases given their relatively high long-term survival rates.

Technical Complications and Prosthesis Survival Rates with Implant-Supported Fixed Complete Dental Prostheses: A Retrospective Study with 1- to 12-Year Follow-Up.

PURPOSE: To report the rate of technical complications and prosthesis survival in a cohort of edentulous patients treated with implant-supported fixed complete dental prostheses (IFCDPs) after a mean observation period of at least 1 year. MATERIALS AND METHODS: The single-visit examination included clinical and radiographic assessment, occlusal analysis, photographs and questionnaire assessing patient satisfaction in a cohort of 52 patients rehabilitated with 71 IFCDPs (supported by 457 implants). The IFCDPs were assessed for technical complications, number of implants and cantilever extension, retention type and prosthetic material type. Comparison was made between ceramic IFCDPs (Group 1) and metal-resin IFCDPs (Group 2). Kaplan-Meier survival curve analysis was carried out for assessment of prosthesis survival and was done for both Groups 1 and 2 separately. The Cox proportional hazard model was used for survival analysis, adjusting for a number of potential confounders, to evaluate the association between prosthesis survival and several risk factors such as type of opposing occlusion, nightguard use, and presence of bruxism. Responses to patient satisfaction questions were compared with Fisher's exact test. RESULTS: Out of 71 edentulous arches (52 patients) restored with IFCDPs, 6 IFCDPs had failed, yielding a cumulative prosthesis survival rate of 91.6 % after a mean observation period of 5.2 years (range: 1-12 years) after definitive prosthesis insertion. Three IFCDPs were lost due to implant failures after 5.8 to 11 years of functional loading. Additionally, 3 metal-resin IFCDPs failed due to technical complications. Minor complications were the most frequent complications observed, namely wear of the prosthetic material (9.8% annual rate) being the most common, followed by decementation of cement-retained IFCDPs (2.9%), and loss of the screw access filing material of the screw-retained IFCDPs (2.7%). The most frequently observed major complication was fracture of the prosthetic material (1.9% annual rate), followed by fracture of occlusal screw (0.3%), and fracture of framework (0.3%). The annual rate of wear of prosthetic material was 7.3% for porcelain IFCDPs (n = 19/55) and 19.4% for metal-resin IFCDPs (n = 13/16), yielding a statistically significant difference between the 2 groups (p = 0.01). CONCLUSIONS: After a mean exposure time of 5.2 years, 91.6% prosthesis survival rates were achieved (65 out of 71 IFCDPs). The most frequent minor technical complication was wear of the prosthetic material with estimated 5-year rate of 49.0%, while the most frequent major complication was fracture of the prosthetic material with estimated 5-year dental unit-based rate of 9.5%. The cumulative rates for "prosthesis free of minor complications" at 5- and 10-years were 60.5% (95% CI: 47.2-71.3%) and 8.9% (95% CI: 2.9-18.0%), respectively. The cumulative rates for "prosthesis free of major technical complications" at 5- and 10-years were 85.5% (95% CI: 73.0-92.5%) and 30.1% (95% CI: 12.0-50.6%), respectively. Presence of bruxism, and absence of a nightguard were associated with increased risk for chipping of the prosthetic material of the IFCDPs.

Complications and survival rates of 55 metal-ceramic implant-supported fixed complete-arch prostheses: A cohort study with mean 5-year follow-up.

STATEMENT OF PROBLEM: Long-term outcomes with metal-ceramic (MC) implant-supported fixed complete dental prostheses (IFCDPs) are scarce. PURPOSE: The purpose of this retrospective study was to assess the rate of biologic and technical complications in a cohort of edentulous patients treated with MC IFCDPs by residents after a mean clinical follow-up of 5 years (range: 1 to 12 years). MATERIAL AND METHODS: Forty-one participants with 55 MC IFCDPs underwent a single-visit comprehensive examination that included a medical and dental history review and clinical and radiographic examinations. All supporting implants and prostheses were examined for biologic and technical complications. Life table analysis and Kaplan-Meier survival curves were calculated. RESULTS: Of 359 moderately rough surface dental implants, 2 had failed in 1 patient after 11 years of functional loading, yielding a cumulative implant survival rate of 99.4%. Owing to the implant failure, 1 of 55 edentulous arches restored with IFCDPs failed, yielding a cumulative prosthesis survival rate of 98.2% after mean observation period of 5.0 years. Soft tissue recession was the most frequent minor biologic complication (annual rate 7.8% at the prosthesis level) for both cement and screw-retained IFCDPs (group C and S), and peri-implantitis (annual rate 1.6% at the implant level) the most frequent major biologic complication. Wear of porcelain (annual rate 8.0% at the prosthesis level) was the most frequent minor technical complication for both groups, and fracture of porcelain (annual rate 0.8% at the dental-unit level) was the most frequent major technical complication. Minor complications were the most frequent in both the groups (cement and screw retained). CONCLUSIONS: High implant and prosthesis survival rates (above 98%) were achieved, yet substantial complication rates were encountered. The most frequent major biologic complication was peri-implantitis, with a 5-year implant-based rate of 8% (95% confidence interval [CI]: 5.8-11.1), whereas the most frequent major complication was fracture of porcelain with a 5-year dental unit-based rate of 4%. The estimated cumulative rates for "prosthesis free of biologic complications" were 50.4% (95% CI: 36.4% to 63.0%) at 5 years and 10.1% (95% CI: 3.5% to 20.8%) at 10 years, whereas for "prosthesis free of technical complications," they were 56.4% (95% CI: 41.7% to 68.8%) at 5 years and 9.8% (95% CI: 3.2% to 21.0%) at 10 years.

Survival rates of short dental implants (≤6 mm) compared with implants longer than 6 mm in posterior jaw areas: A meta-analysis.

PURPOSE: To systematically review randomized controlled clinical trials (RCTs) reporting on the long-term survival and failure rates, as well as the complications of short implants (≤6 mm) versus longer implants (>6 mm) in posterior jaw areas. MATERIALS AND METHODS: Electronic and manual searches were conducted to identify studies, specifically RCTs, reporting on short dental implants (≤6 mm) and their survival and complication rates compared with implants longer than 6 mm. Secondary outcomes analyzed were marginal bone loss and prosthesis survival rates. RESULTS: Ten RCTs fulfilled the inclusion criteria and featured a total of 637 short (≤6 mm) implants placed in 392 patients, while 653 standard implants (>6 mm) were inserted in 383 patients. The short implant survival rate ranged from 86.7% to 100%, whereas standard implant survival rate ranged from 95% to 100% with a follow-up from 1 to 5 years. The risk ratio (RR) for short implant failure compared to standard implants was 1.29 (95% CI: 0.67, 2.50, p = 0.45), demonstrating that overall, short implants presented higher risk of failure compared to longer implants. The heterogeneity test did not reach statistical significance (p = 0.67), suggesting low between-study heterogeneity. The prosthesis survival rates from the short implant groups ranged from 90% to 100% and from 95% to 100% for longer implant groups, respectively. CONCLUSION: Short implants (≤6 mm) were found to have higher variability and lower predictability in survival rates compared to longer implants (>6 mm) after periods of 1-5 years in function. The mean survival rate was 96% (range: 86.7%-100%) for short implants, and 98% (range 95%-100%) for longer implants. Based on the quantity and quality of the evidence provided by 10 RCTs, short implants with ≤6 mm length should be carefully selected because they may present a greater risk for failure compared to implants longer than 6 mm.

Implant survival rates and biologic complications with implant-supported fixed complete dental prostheses: A retrospective study with up to 12-year follow-up.

OBJECTIVES: To assess the rate of biologic complications and implant survival in edentulous patients treated with implant-supported fixed complete dental prostheses (IFCDPs) after a mean observation period of 5.2 years (range: 1-12 years). MATERIALS AND METHODS: A single-visit clinical and radiographic examination was performed to assess types and rates of biologic complications with ceramic IFCDPs (Group 1) and metal-resin IFCDPs (Group 2). RESULTS: Of 457 rough surface dental implants supporting 71 IFCDPs (52 patients), six had failed, yielding an implant survival rate of 98.7% after a mean observation period of 5.2 years after definitive prosthesis insertion. The most frequent minor biologic complication was soft tissue recession (7.7% annual rate), inflammation under the IFCDP (7.4% annual rate), and peri-implant mucositis (6.3% annual rate). The most frequent major biologic complication was peri-implantitis (2.0% annual rate), in 46/457 implants (10.1%) supporting 19 IFCDPs and late implant failure (0.3% annual rate). The frequency of biologic complications was not statistically different between Group 1 and Group 2. The presence of high plaque index had significant effect on bone loss. CONCLUSIONS: After a mean exposure time of 5.2 years postdefinitive prosthesis insertion (range: 1-12 years), implant survival rate of 98.7% was achieved. The six implant failures in three patients occurred after 5 years and affected the prosthesis survival. Soft tissue recession was the most frequent minor biologic complication, whereas peri-implantitis was the most frequent major biologic complication. A 10-year implant-based mucosal recession rate of 77% (95% CI: 68.2-87.9) and a 10-year implant-based peri-implantitis rate of 20% (95% CI: 16.9-24.9) were found.

Building oral health research infrastructure: the first national oral health survey of Rwanda.

BACKGROUND: Oral health affects quality of life and is linked to overall health. Enhanced oral health research is needed in low- and middle-income countries to develop strategies that reduce the burden of oral disease, improve oral health and inform oral health workforce and infrastructure development decisions. OBJECTIVE: To implement the first National Oral Health Survey of Rwanda to assess the oral disease burden and inform oral health promotion strategies. METHODS: In this cross-sectional study, sample size and site selection were based on the World Health Organization (WHO) Oral Health Surveys Pathfinder stratified cluster methodologies. Randomly selected 15 sites included 2 in the capital city, 2 other urban centers and 11 rural locations representing all provinces and rural/urban population distribution. A minimum of 125 individuals from each of 5 age groups were included at each site. A Computer Assisted Personal Instrument (CAPI) was developed to administer the study instrument. RESULTS: Nearly two-thirds (64.9%) of the 2097 participants had caries experience and 54.3% had untreated caries. Among adults 20 years of age and older, 32.4% had substantial oral debris and 60.0% had calculus. A majority (70.6%) had never visited an oral health provider. Quality-of-life challenges due to oral diseases/conditions including pain, difficulty chewing, self-consciousness, and difficulty participating in usual activities was reported at 63.9%, 42.2% 36.2%, 35.4% respectively. CONCLUSION: The first National Oral Health Survey of Rwanda was a collaboration of the Ministry of Health of Rwanda, the University of Rwanda Schools of Dentistry and Public Health, the Rwanda Dental Surgeons and Dental (Therapists) Associations, and Tufts University and Harvard University Schools of Dental Medicine. The international effort contributed to building oral health research capacity and resulted in a national oral health database of oral disease burden. This information is essential for developing oral disease prevention and management strategies as well as oral health workforce and infrastructure.

Factors Associated with Evidence-Based Clinical Questions Presented in a Vertically Integrated Seminar Series at a U.S. Dental School.

The Basic Science/Clinical Science Spiral Seminar Series (BaSiCSsss) was implemented at Tufts University School of Dental Medicine in 2013. In the series, teams of dental students from all four years presented components of a clinical case, supported by evidence-based dentistry concepts. The role of the third-year student on each team was to present questions based on the PICO (Population, Intervention, Comparison, Outcome) method to support the treatment plan for the selected case. The primary aim of this study was to identify the dental discipline from which the PICO question was chosen, and the secondary aim was to review the level of evidence (journal impact factor, study design, and year of publication) of sources used to support the PICO questions. Presentations compiled during the 2014-15 and 2015-16 academic years were reviewed. The PICO questions and additional details from the publications used as reference (choice of journal, year of publication, study design) were reviewed. A total of 224 presentations were reviewed. The results showed that most topics were from the subjects of periodontology and prosthodontics. Systematic reviews and cohort studies were the most often used types of study design. The majority of the articles cited were recently published. The students used supporting references for the clinical questions published recently with a high level of evidence.

Integrating student feedback during "Dental Curriculum Hack-A-thon".

BACKGROUND: The future of dental education is at crossroads. This study used the parameter of the 2016 Dental Curriculum Hack-a-Thon to assess intra- and inter-institutional agreement between student and faculty views regarding dental curriculums to determine if there is an impact in student perceptions towards dental education from before and after the event. METHODS: This exploratory, cross-sectional study involved two surveys, with Survey 1 being distributed among four faculty-student pairs of the four participating dental schools answering 14 questions. Survey 2 assessed the views of 20 participating dental students through 26 questions in a pre- and post- event survey design. Descriptive statistics were used to explore differences in perceptions towards dental education across both instrument surveys. RESULTS: The results revealed valuable student insights regarding intra- and inter-institutional agreement relevant for the change in dental curriculum that needs to occur. Survey 2 revealed that mandatory attendance in didactic courses, electronic based examination preferences, and the preference of preclinical courses being held in the first and second years of a four-year dental curriculum were of particular importance to student participants. CONCLUSIONS: The results of this study indicate that exposure and participation in subjects pertaining to dental education can be influential on student preferences and opinions on how dental education should be delivered in a four-year curriculum.

Association Between Sinus Membrane Thickness and Membrane Perforation in Lateral Window Sinus Augmentation: A Retrospective Study.

BACKGROUND: Association between Schneiderian membrane thickness and membrane perforation is examined in lateral window sinus augmentation. METHODS: This retrospective study reviewed records of 551 patients who underwent lateral sinus augmentation at Tufts University School of Dental Medicine, Boston, Massachusetts, from June 1, 2006 to May 31, 2015. Preoperative cone-beam computed tomography images were analyzed to evaluate possible association among membrane thickness, residual bone height, and membrane perforation. Data were evaluated using Mann-Whitney U test at P <0.05. RESULTS: Total 167 patients (95 males and 72 females) met the eligibility criteria and were included in the study. Among them, 47 patients had Schneiderian membrane perforation (perforation group). Mean membrane thickness was 0.84 ± 0.67 mm in the perforation group and 2.65 ± 4.02 mm in the non-perforation group. There was a statistically significant difference in membrane thickness between groups (P <0.001). Mean residual ridge thickness was 2.78 ± 1.37 mm in the perforation group and 4.21 ± 2.09 mm in the non-perforation group. There was a statistically significant difference in residual alveolar bone height (P <0.001). CONCLUSIONS: Patients who experienced membrane perforation had a thinner membrane compared with patients without membrane perforation. Schneiderian membrane perforation was associated with decreased residual bone height.

The Benefit of a Switch: Answer-Changing on Multiple-Choice Exams by First-Year Dental Students.

The aim of this study was to determine if dental students would benefit from changing their initial responses to what they have deemed to be more suitable answers during high-stakes multiple-choice examinations. Students are often advised to stay with their first answers despite evidence from other fields suggesting this is not the best course for obtaining optimal final exam scores. Data were collected for 160 first-year DMD students in fall 2013 for three operative dentistry and four biochemistry exams at Tufts University School of Dental Medicine. As students take all of their exams through ExamSoft, a test-taking software application that tracks and records all changes students make during the exam period, the subjective nature of previous studies on answer changing was eliminated. The results showed that all students changed their answers on a minimum of nine questions over the seven exams, with an average of 26.55 (SD=8.8) questions changed per student. Answers changed from an incorrect to a correct response comprised nearly 65% of total answer changes, while changes from a correct to an incorrect answer encompassed slightly above 10% of answer changes. Nearly all students (99.4%) benefitted from answer-changing with a net gain of at least two correct questions, with only one student not increasing the final score. Overall, the students greatly benefitted from changing their answer choice, suggesting that dental students could be advised to change their answers from their first choice if they identify a better option when taking multiple-choice exams.

The accuracy of linear measurements of maxillary and mandibular edentulous sites in cone-beam computed tomography images with different fields of view and voxel sizes under simulated clinical conditions.

PURPOSE: The objective of this study was to investigate the effect of varying resolutions of cone-beam computed tomography images on the accuracy of linear measurements of edentulous areas in human cadaver heads. Intact cadaver heads were used to simulate a clinical situation. MATERIALS AND METHODS: Fiduciary markers were placed in the edentulous areas of 4 intact embalmed cadaver heads. The heads were scanned with two different CBCT units using a large field of view (13 cm×16 cm) and small field of view (5 cm×8 cm) at varying voxel sizes (0.3 mm, 0.2 mm, and 0.16 mm). The ground truth was established with digital caliper measurements. The imaging measurements were then compared with caliper measurements to determine accuracy. RESULTS: The Wilcoxon signed rank test revealed no statistically significant difference between the medians of the physical measurements obtained with calipers and the medians of the CBCT measurements. A comparison of accuracy among the different imaging protocols revealed no significant differences as determined by the Friedman test. The intraclass correlation coefficient was 0.961, indicating excellent reproducibility. Inter-observer variability was determined graphically with a Bland-Altman plot and by calculating the intraclass correlation coefficient. The Bland-Altman plot indicated very good reproducibility for smaller measurements but larger discrepancies with larger measurements. CONCLUSION: The CBCT-based linear measurements in the edentulous sites using different voxel sizes and FOVs are accurate compared with the direct caliper measurements of these sites. Higher resolution CBCT images with smaller voxel size did not result in greater accuracy of the linear measurements.