Effect of Various Toothpaste Tablets on Gloss and Surface Roughness of Resin-based Composite Materials

OBJECTIVES

To evaluate the effect of various toothpaste tablets on gloss and surface roughness of resin-based composite.

METHODS AND MATERIALS

Sixty-four resin-based composite specimens were divided into four groups of 16 specimens each. Gloss and roughness were measured before and after simulated brushing with three types of toothpaste tablets and one conventional toothpaste: CT: Chewtab Toothpaste Tablets; AT: Anticavity Toothpaste Tablets; HC: Charcoal Toothpaste Tablets; CP: Cavity Protection toothpaste. The Kruskal- Wallis procedure was performed to compare the differences by groups. Post-hoc comparisons were conducted with Bonferroni corrections (α=0.05).

RESULTS

There was a significant drop in gloss for all groups. CT and AT maintained the highest gloss with means of 81.6 GU and 74.1 GU, respectively. The lowest gloss of 24.5 GU was observed for HC. There was a significant increase in roughness for all groups except for CT. CT had the lowest roughness with a mean of 0.034 μm, while HC had the highest roughness with a mean of 0.074 μm. There was a significant correlation between post-brushing gloss and post-brushing roughness (p<0.001, r=-0.884).

CONCLUSION

Chewtab Toothpaste Tablets had the least effect on gloss and roughness, while Charcoal Toothpaste Tablets had the most negative effect on the surface properties of resin-based composites.

Evaluating a method of creating artificial caries in typodont teeth for teaching Class III cavity preparations

OBJECTIVES

The purpose of the study was to report a step-by-step process of creating artificial caries typodont teeth and to determine the perception and efficacy of their use in preclinical operative training.

METHODS

Artificial caries material comprised of commercially available hide glue and chocolate powder for more realistic coloring was embedded into the distolingual of #9 ModuPRO plastic typodont teeth. First-year dental students having no clinical experience in excavating Class III cavity preparations were divided into two groups. Group BA prepared conventional typodont teeth (CTT) first, then artificial caries typodont teeth. Group AB prepared the ACT first, then CTT. The preps were scored employing a rubric used in the operative dentistry course class. A feedback questionnaire was conducted to rate students' satisfaction regarding the use of ACT and CTT. The Mann-Whitney U-test was used to compare the scores between groups ACT-CTT and CTT-ACT and the Chi-Square test was used to evaluate the positive and negative questionnaire responses.

RESULTS

The two groups showed no significant difference in grades and no significant changes in their scores regardless of which order they prepped the teeth (P > 0.05). The questionnaire heavily favored the use of artificial caries typodont teeth (P < 0.05).

CONCLUSIONS

The artificial caries typodont teeth protocol described in this study was feasible when implemented at the preclinical laboratory instruction level with positive questionnaire feedback from dental students.

Prediction of In-Hospital Mortality Following Vertebral Fracture Fixation in Patients With Ankylosing Spondylitis or Diffuse Idiopathic Skeletal Hyperostosis: Machine Learning Analysis

BACKGROUND

Ankylosing spondylitis (AS) and diffuse idiopathic skeletal hyperostosis (DISH) are distinct pathological entities that similarly increase the risk of vertebral fractures. Such fractures can be clinically devastating and frequently portend significant neurological injury, thus making their prevention a critical focus. Of particular significance, spinal fractures in patients with AS or DISH carry a considerable risk of mortality, with reports on 1-year injury-related deaths ranging from 24% to 33%. As such, the purpose of this study was to conduct machine learning (ML) analysis to predict postoperative mortality in patients with AS or DISH using the Nationwide Inpatient Sample Healthcare Cost and Utilization Project (HCUP-NIS) database.

METHODS

HCUP-NIS was queried to identify adult patients carrying a diagnosis of AS or DISH who were admitted for spinal fractures and underwent subsequent fusion or corpectomy between 2016 and 2018. Predictions of in-hospital mortality in this cohort were then generated by three independent ML algorithms.

RESULTS

An in-hospital mortality rate of 5.40% was observed in our selected population, including a rate of 6.35% in patients with AS, 2.81% in patients with DISH, and 8.33% in patients with both diagnoses. Increasing age, hypertension with end-organ complications, spinal cord injury, and cervical spinal fractures each carried considerable predictive importance across the algorithms utilized in our analysis. Predictions were generated with an average area under the curve of 0.758.

CONCLUSIONS

This study's application of ML algorithms to predict in-hospital mortality among patients with AS or DISH identified a number of clinical risk factors relevant to this outcome.

CLINICAL RELEVANCE

These findings may serve to provide physicians with an awareness of risk factors for in-hospital mortality and, subsequently, guide management and shared decision-making among patients with AS or DISH.

LEVEL OF EVIDENCE: 4

The Effect of Calcium Hydroxide Pastes on Isolated Vital Nerve Fibers

INTRODUCTION

Calcium hydroxide pastes (CHPs), commonly used for disinfecting root canals during endodontic treatment, are generally considered safe. However, accidental extrusions result in minimal injuries and little to no discomfort, except when extruded pastes come into contact with nerve bundles, such as the inferior alveolar nerve. Currently, there is a lack of information about the possible role of specific paste vehicles on the extent of nerve injury. The purpose of this study was to compare the role that paste vehicles, such as water or methylcellulose, may play when nerve fibers are exposed to CHP.

METHODS

Isolated sciatic nerves of Sprague-Dawley rats were exposed to either water-based or methylcellulose-based CHP for varying durations of time (30, 60, or 90 minutes). Histopathological changes, including axonal edema, myelin alterations, and loss of cellular outlines, were assessed, and the degrees of changes were compared using chi-square intraclass correlation coefficient tests.

RESULTS

Both groups exposed to the pastes demonstrated varying degrees of histopathologic changes, including axonal edema, myelin changes, and loss of cellular outlines, at different exposure times. The water-based calcium hydroxide paste induced these changes more rapidly than the methylcellulose-based paste. Similar patterns were observed in the scanning electron microscopic findings. Exposure time emerged as an important difference in the effects of the 2 pastes. In each of these tests, all observations of water-based paste exposure were rated as moderate to severe, whereas the observed cellular changes (axonal, myelin, and intact cellular outline) were rated as mild to moderate after exposure to methylcellulose-based paste for the same exposure durations. The chi-square tests indicated a statistically significant association between the material and each of the outcomes (axonal changes: χ²15 = 81.0, P < .001; myelin changes: χ²15 = 81.0, P < .001; intact cellular outline, χ²15 = 81.0, P < .001). The intraclass correlation coefficient value was 0.93.

CONCLUSIONS

The study demonstrates that axonal and myelin damage increase with longer exposure times, with water-based CHP causing more damage than methylcellulose-based CHP at each time point.

Comparison of the Efficacy and Safety of Pulp Sensitivity Testing Results Using a New Pulp Testing Device versus Some Commonly Used Methods: A Crossover Study

INTRODUCTION

The efficacy and safety of a single novel electronic pulp sensitivity tester with a transilluminator (PSTT) capable of providing 4 different tests was compared with gold standard (GS) pulp testing methods.

METHODS

Four hundred eighty teeth, including 3 from each quadrant and their contralateral and opposing teeth, were randomly assessed using the PSTT or GS methods. Seven days later, the same teeth were assessed using the method not used earlier so that all teeth were evaluated using both methods. Sixty previously root canal-treated teeth, serving as negative controls, were assessed identically to the experimental groups. Results were analyzed using IBM SPSS software (IBM Corp, Armonk, NY) (P < .05).

RESULTS

A higher percentage of teeth responded to cold and electricity using GS methods compared with the PSTT (99.4 vs 93.1 and 99.6 vs 97.3, respectively). A lower percentage of teeth responded to heat using the GS method compared with the PSTT (50.0 vs 68.1). Chi-square tests determined differences in the proportion of sensitivity to temperature, and electric testing methods were statistically significant (P < .001 and P = .004, respectively). No difference in the proportion of sensitivity was observed for transillumination. The Wilcoxon signed rank test determined significantly shorter cold testing times using the GS method (P = .024). Shorter testing times were observed using the PSTT for heat (P < .001), electric pulp testing (P = .048), and transillumination (P = .001). The overall PSTT testing time was significantly shorter than the GS testing time (P = .03). Tissue injury was not observed.

CONCLUSIONS

The PSTT efficiently and safely provided heat and transillumination for pulpal diagnosis. Improvements are needed to enhance the cold and electric stimulus efficacy.

Impact of Dental Institutions' Values on Students' Intent to Practice in Underserved Communities: A Cross-sectional Study

AIM

To evaluate how an institution's values can impact students' intent to practice in underserved areas.

MATERIALS AND METHODS

The values of 71 accredited dental schools in the United States were searched and tabulated. The American Dental Education Association (ADEA) survey results were used to tabulate the desire to serve the underserved population before entering dental school and upon graduation. Additionally, responses on the total amount of educational debt on graduation was compiled for LLUSD and all other dental schools. Fisher's exact test was performed to compare the difference between the two cohorts and Wilcoxon test was used to assess difference within the groups. Tests were conducted at an alpha level of 0.05 with SAS v 9.1.3 (SAS Institute, Cary, NC, USA).

RESULTS

The top five values of US dental institutions based on frequency were excellence, diversity/inclusion, integrity, innovation, and respect. There was no statistically significant difference between LLUSD and all other dental schools in their desire to serve the underserved community upon graduation (p > 0.05, in all instances). Overall, there was a trend that upon graduation, the desire to serve the underserved had less impact on students' decision-making on their career choices. This drop in the desire to serve the underserved was statistically significant within both cohorts in the year 2021 (p < 0.001).

CONCLUSIONS

Dental institutions should focus on better understanding of how their values impact their students' career choices so that they can develop strategies to better align their values with the mission of addressing the dentist shortage in underserved areas.

CLINICAL SIGNIFICANCE

Dental institutions' values play a major role in impacting students' career choices upon graduation and should be assessed using metrics that are measurable.

A comparison of toothpaste tablets and a sodium fluoride dentifrice for the control of supragingival plaque and gingivitis: A 2-week randomized controlled trial

PURPOSE

To compare toothpaste tablets containing 0.243% sodium fluoride and a conventional sodium fluoride dentifrice for gingivitis and plaque control over a 2-week period.

METHODS

Forty adult participants were randomized into two groups: Toothpaste tablets (Colgate Anywhere Travel Toothpaste Tablets) and conventional dentifrice (Colgate Cavity Protection). A blinded examiner measured the gingival and plaque index at baseline and after 2 weeks. A questionnaire was distributed at the end to determine overall satisfaction of the product used. Statistical analyses were performed separately for the gingival index and plaque index scores. Comparisons of the two treatment groups with respect to baseline and 2-week gingival index and plaque index scores were performed using Mann-Whitney U-test. Within-treatment comparisons of the gingival index and plaque index scores obtained at the 2-week examinations versus baseline were performed using Wilcoxon test.

RESULTS

Both groups had statistically significant improvements in plaque control at the 2-week visit (P< 0.05). There was no statistically significant difference between groups for gingival and plaque index at the 2-week visit (P> 0.05). Overall satisfaction for both products were positive while perception on "texture/foaminess" was more negative for toothpaste tablets (P= 0.001). The results showed that toothpaste tablets' short-term performance on gingivitis and plaque control was equivalent to conventional dentifrice while the " texture/foaminess" of toothpaste tablets was found to be less appealing.

CLINICAL SIGNIFICANCE

Toothpaste tablets are a relatively new form of toothpaste that can be a viable alternative to conventional dentifrice with the added benefit of an eco-friendly way of maintaining oral hygiene.

Effect of toothpaste tablets on gloss and surface roughness of resin-based composite materials

PURPOSE

To evaluate the effects of toothpaste tablets on the gloss and surface roughness of resin-based composite materials and determine the relationship between gloss and roughness.

METHODS

Rectangular jigs were designed and printed. Wells (2 mm deep x 7 mm diameter) were filled with Filtek Supreme Ultra A2B, light-cured and polished. A small-area glossmeter was used for gloss (GU) measurements and a profilometer for roughness measurements (Ra) at baseline and after challenge with each toothpaste. An automated tooth-brushing machine was set at 120 strokes/minute for a total of 10,000 strokes to evaluate four test groups with 16 specimens in each group. NC: Brushing with distilled water; TABS: Colgate Anywhere Travel Tooth Tabs; CP: Colgate Cavity Protection Toothpaste and AW: Colgate Whitening Advanced Toothpaste. Kruskal-Wallis test was used to test the difference in gloss and surface roughness among the groups and Pearson correlation was used to compare the relationship between gloss and roughness.

RESULTS

There was no statistically significant difference in gloss and roughness among the four groups at baseline. At post-brushing, there was a statistically significant difference among the groups (P< 0.001) with increased roughness and decreased gloss for CP and AW when compared to TABS. There was a statistically significant correlation between post-brushing roughness and post-brushing gloss (P< 0.001, rho: -0.815). Thus, the higher the surface roughness the lower the gloss.

CLINICAL SIGNIFICANCE

Toothpaste tablets retain better gloss and roughness of resin-based composite materials when compared to conventional toothpastes.

Assessing Adherence to Provider's Recommendations in Caries Risk Assessment and Management: A Retrospective Data Review

AIM

To evaluate the distribution of caries risk category of patients at a dental institution and determine adherence to providers' recommendations.

MATERIALS AND METHODS

A cross-sectional retrospective review of 1,235 patients records that included data collection on demographics, the sum of the number of decayed, missing due to caries, and filled teeth in the permanent teeth (DMFT), presence of frequent snacking, stimulated salivary flow rate, stimulated saliva pH, saliva buffering capacity, biofilm activity, caries risk category, anti-caries prescription accept/decline, and change in the caries risk category. Statistical analysis was carried out through Pearson's Chi-squared test and linear model ANOVA with a significance level of 0.05.

RESULTS

Pearson's Chi-squared test showed a statistically significant difference in frequency by risk category (p < 0.001) indicating that patients were skewed toward high and extreme caries risk. Linear model ANOVA showed that higher risk categories were associated with lower salivary flow rates (p = 0.010) and higher biofilm activity (p < 0.001). About, 1 out of 3 patients were reported to have frequent snacking (N = 391, 32%). Frequent snacking patients were more likely to present with higher caries risk assessment (p < 0.001), younger age (p < 0.001), and female (p < 0.001). Despite recommendations from the dental student provider, only 27% accepted the anti-cavity prescriptions while 61% declined the recommendation.

CONCLUSION

Distribution of caries risk category is not evenly distributed, but rather skewed toward high and extreme caries risk levels. Despite the identified risks, there is low adherence to the recommendations provided by healthcare providers. The results underscore the necessity for targeted interventions and initiatives aimed at fostering behavioral changes to enhance oral health outcomes.

CLINICAL SIGNIFICANCE

There is a high need for targeted interventions and initiatives that promote behavioral changes to enhance oral health outcomes.

Dental Students’ Knowledge, Attitude, and Confidence toward Evidence-based Dentistry: A 5-year Retrospective Study

AIM

The purpose was to assess dental students' knowledge, attitude, and confidence toward evidence-based dentistry in five graduating Doctor of Dental Surgery (DDS) classes.

MATERIALS AND METHODS

All dental students (class of 2019, 2020, 2021, 2022, and 2023) enrolled in the D3 research design course were required to take a pre-Knowledge, Attitude, and Confidence in Evidence-based Dentistry (KACE) survey. On completion of the 11-week course, a post-KACE survey was distributed to compare the differences in the three domains of evidence-based dentistry (EBD). For the knowledge domain, the responses from the 10 questions were converted to either correct (1) or wrong (0) so that the compiled scores could range from 0 to 10. The attitudes and confidence domains used a five-point Likert scale. The compiled attitude score was a sum of the responses from 10 questions yielding a range from 10 to 50. For confidence, the compiled score ranged from 6 to 30.

RESULTS

The mean knowledge scores of all classes together before and after training were 2.7 and 4.4, respectively. Overall, there was a statistically significant difference between pre- and post-knowledge indicating an improvement in knowledge associated with the training (p < 0.001). The mean attitudes of all classes together before and after the training were 35.3 and 37.2, respectively. Overall, there was a statistically significant improvement in attitude (p < 0.001). The values of mean confidence of all classes together before and after the training were 15.3 and 19.5, respectively. Overall, there was a statistically significant improvement in confidence (p < 0.001).

CONCLUSIONS

A dental curriculum emphasizing Evidence-based practice (EBD) resulted in increased knowledge acquisition, improved attitude, and confidence toward EBD of dental students.

CLINICAL SIGNIFICANCE

Educational initiatives emphasizing evidence-based dentistry increase students' knowledge acquisition, improved attitude, and confidence toward EBD that may also translate to active implementation of EBD in their future practices.

Correlation of spinal epidural fat volume with body mass index: a longitudinal study

PURPOSE

Spinal epidural lipomatosis is abnormal accumulation of normal fat in the epidural space with weight loss suggested as first-line therapy in select symptomatic patients. However, moderate to large longitudinal studies establishing concordant changes between body mass index and epidural fat are lacking. The purpose of this study was to longitudinally assess this relationship.

METHODS

We performed an ancillary study of the Habitual Diet and Avocado Trial. Baseline and six-month abdominal MRIs were analyzed for 98 overweight or obese but otherwise healthy subjects. Dorsal epidural fat volumes in the lumbar spine were measured and correlated with changes in body mass index, changes in visceral fat volume, and demographic information.

RESULTS

There was a linear relationship between body mass index changes and epidural fat volume changes with a one-point change in body mass index corresponding to a 45 mm³ change in dorsal epidural fat volume (p < 0.001, 95% CI 31.87 to 76.77) as well as between visceral fat volume changes and epidural fat volume changes (regression coefficient 0.51, p < 0.001, 95% CI 0.22 to 0.47). Age was inversely related with subjects older than 45.7 years tending to lose epidural fat (regression coefficient -0.22, p = 0.025, 95% CI -10.43 to -0.72).

CONCLUSION

Changes in spinal dorsal epidural fat volume parallel changes in body mass index and visceral fat, supporting weight loss as initial treatment for uncomplicated obesity-associated spinal epidural lipomatosis.

Tooth Color Change and Erosion: Hydrogen Peroxide Versus Non-peroxide Whitening Strips

AIM

The study evaluated the efficacy and potential erosion of non-peroxide strips compared to hydrogen peroxide (HP) whitening strips (WSs).

METHODS

Color evaluation samples (N=64) were distributed into four groups and treated according to manufacturer's directions. NC: Negative control treated with water; BT: Non-peroxide Brilliant Dissolving Strips; FM: Non-peroxide Fancymay Teeth WSs; WS: Crest 3D Brilliance HP White Strips. A contact-type spectrophotometer was used to measure color at baseline (T1), 1-day posttreatment (T2), and 1-week posttreatment (T3). Teeth were cut to a rectangular block for micro-CT erosion assessment. The samples (N=30) were divided into five groups. In addition to the four groups for color assessment, a positive control (PC) treated with 0.25% citric acid was added. The samples were scanned, reconstructed, and measured for erosion depth using a micro-CT analysis program software. Kruskal-Wallis test was used to determine differences in color change and erosion depth among the groups. Tests of hypotheses were two-sided with an alpha level of 0.05.

RESULTS

The mean ΔE*ab at 1-day/1-week posttreatment were 2.4/2.5, 2.8/2.9, 2.8/3.2, and 8.6/11.0 for NC, BT, FM, and WS, respectively. There was a statistically significant difference for ΔE*ab at 1-day and 1-week posttreatment (p<0.001). Group WS had the highest color change, while the other three groups did not differ from each other (p>0.05). Mean erosion depths in microns were 0.52, 0.58, 0.42, 0.49, and 29.55 for NC, BT, FM, WS, and PC, respectively. There was a statistically significant difference among the groups (p=0.004). Group PC had the greatest erosion, while the other groups had negligible erosion that did not differ from each other (p>0.05).

CONCLUSION

Peroxide WSs had superior whitening efficacy compared to non-peroxide strips. None of the tested products compromised tooth structure integrity through enamel erosion.

The Outcome of a New Teledentistry Initiative in Response to the COVID-19 Pandemic: A Cross-sectional Study

AIM

The purpose of this study was to assess the overall satisfaction of a new learning experience and evaluate the outcome of LLUSD's educational teledentistry initiative through a survey based on Kirkpatrick's multidimensional model of training evaluation.

MATERIALS AND METHODS

An IRB application was approved (#5210385) for a cross-sectional study that included Loma Linda University School of Dentistry (LLUSD) dental students of the class of 2022 and 2023. The 9-question survey consisted of three sections. The first section included demographic questions on gender and the graduating class. The second section was related to perceived teaching effectiveness, attitude, behavior, and significance. The third section included an open-ended question. The survey was distributed by three student investigators. Descriptive statistics were calculated, and categorical variables were compared using the Chi-squared test (χ² test).

RESULTS

The perceived teaching effectiveness of the newly implemented educational initiative was high for increasing the ability to communicate with patients and for screening and identifying the need for referrals. A majority of students believed that teledentistry is an important means to improve patients' access to dental care and that the School has been providing a good educational environment in providing teledentistry sessions to patients. There were no significant differences in the frequencies of positive and negative responses to all questions (N = 6) by gender and by class (p >0.05, in all instances).

CONCLUSIONS

Teledentistry eVisits allowed the continuation of patient contact and initial assimilation of patient information. There is potential for this educational initiative to be more actively and comprehensively implemented in the future.

CLINICAL SIGNIFICANCE

New educational initiatives allow the continuation of patient contact that will ensure that students will graduate as competent oral health care providers despite challenges imposed by the pandemic.

BigMouth: development and maintenance of a successful dental data repository

Few clinical datasets exist in dentistry to conduct secondary research. Hence, a novel dental data repository called BigMouth was developed, which has grown to include 11 academic institutions contributing Electronic Health Record data on over 4.5 million patients. The primary purpose for BigMouth is to serve as a high-quality resource for rapidly conducting oral health-related research. BigMouth allows for assessing the oral health status of a diverse US patient population; provides rationale and evidence for new oral health care delivery modes; and embraces the specific oral health research education mission. A data governance framework that encouraged data sharing while controlling contributed data was initially developed. This transformed over time into a mature framework, including a fee schedule for data requests and allowing access to researchers from noncontributing institutions. Adoption of BigMouth helps to foster new collaborations between clinical, epidemiological, statistical, and informatics experts and provides an additional venue for professional development.

Impact of COVID-19 on Teaching the Tooth Morphology Course to the New Generation of Learners: A Cross-sectional Study

AIM

The purpose of the study was two-fold. First, to evaluate students' learning style and relate it to their academic performance. Second, to highlight changes implemented in the tooth morphology (TOMO) course as a response to the coronavirus disease-2019 (COVID-19) pandemic.

MATERIALS AND METHODS

The study was performed during 2021-2022 with 101 dental students. Didactic lectures were delivered online and students challenged with nine quizzes and one final examination. Didactic score was calculated by averaging the scores of quizzes and the final exam. Lab score was a combination of five lab projects and the final competency. At course completion, students received a survey on their learning style and how they would like to receive feedback. Kruskal-Wallis test was used to assess differences in didactic and lab scores among groups.

RESULTS

Many students perceived themselves as visual learners (39%) followed by kinesthetic (24%), aural (19%), and reader (18%). There was no difference among learning style groups in performance of didactic (p = 0.340) and lab scores (p = 0.845). Students preferred that the instructor talks them through the questions for feedback on quizzes (41%) while they preferred demonstrations when receiving feedback on their wax-ups (51%). Most students (75%) preferred a TOMO teacher that uses demonstrations. 2020-2021 marked the year of the pandemic where all lectures were delivered online and waxing projects were performed at-home. A postpandemic transformation occurred during 2021-2022, reverting to conventional in-person lab sessions while keeping online didactic lectures.

CONCLUSION

We conclude that TOMO should be delivered by using various teaching styles rather than focusing on a single method while providing more demonstrations.

CLINICAL SIGNIFICANCE

Teaching tooth morphology to the new generation type of learners efficiently will affect the clinical work of dental graduates.

Laboratory model to evaluate efficacy of an experimental titanium oxide nanofibers bleaching agent

Objectives

This study aimed to use a laboratory model to evaluate the efficacy of an experimental bleaching agent.

Materials and Methods

The model used human extracted molars that were treated and measured for bleaching efficacy. Teeth (n = 50) were distributed into 5 groups: Negative control (NC): immersion in water for 8 hours; Nanofibers (NFs): Experimental titanium dioxide nanofibers with stirring and light activation for 8 hours; Whitestrips (WS): Crest 3D White Glamorous White Whitestrips, 2 applications daily for 30 minutes, 14 days; 1% hydrogen peroxide (HP) standard: 1% hydrogen peroxide for 8 hours; and 30% HP standard: 30% hydrogen peroxide for 8 hours. Instrumental measurements were performed using a spectrophotometer. Results were recorded at baseline, 1-day post-bleaching, and 1-week post-bleaching. Kruskal-Wallis procedure was used to determine differences in color change. Pearson correlation was used to evaluate the relationship between visual and instrumental measurements. Tests of hypotheses were 2-sided with alpha = 0.05.

Results

There was no significant difference in color parameters (L1, a1, b1, and shade guide units [SGU]) at baseline (p > 0.05). There was a significant difference among the groups for overall color change (ΔE*ab) and change in shade guide units (ΔSGU) at 1-day and 1-week post-bleaching (p < 0.05). The higher the HP concentration, the higher the color change as expressed in ΔSGU and ΔE*ab. The negative control exceeded the perceptibility threshold of ΔE* = 1.2 regardless of time point. NFs showed a decrease in chroma, but were not statistically different compared to the negative control.

Conclusions

The laboratory model was successful in screening an experimental bleaching agent.

Effect of charcoal dentifrices on tooth whitening and enamel surface roughness

PURPOSE

To evaluate tooth color change and surface roughness after the use of charcoal dentifrices.

METHODS

Bovine teeth (n= 64) used for color measurements were stained in tea solution and embedded in acrylic resin. Specimens were randomized into four groups of 16 specimens each. Cavity Protection (Colgate-Palmolive) was the negative control. Whitening dentifrices used were Black is White (Curaden AG); and My Magic Mud (Carbon and Clay Company) containing activated charcoal and Optic White (Colgate-Palmolive) containing hydrogen peroxide. Instrumental color measurements were performed at baseline, 1-week post-brushing, 30-day post-brushing, and 1-month follow-up. Another set of bovine teeth (n= 64) used for roughness measurements were embedded in acrylic resin and the surface ground flat. The experimental groups and brushing protocol were the same as for the color evaluation part. Surface roughness was measured with a contact type profilometer at baseline and after the last brushing session. Kruskal-Wallis procedure tested changes in color and surface roughness among the different groups. All post-hoc comparisons were conducted with Bonferroni corrections. Tests of hypotheses were two-sided with an alpha level at 0.05.

RESULTS

Overall color change was not significantly different among groups at 1-week post-brushing and at 1-month follow-up. However, the hydrogen peroxide group had a significantly higher reduction in chroma in the yellow-blue axis when compared to negative control group at 30-day post-brushing and 1-month follow-up (P< 0.05). There was no significant difference in roughness among the groups at baseline (P= 0.2973) and post treatment (P= 0.8169).

CLINICAL SIGNIFICANCE

The use of charcoal dentifrices did not have the claimed whitening effect but did not increase enamel surface roughness.

Micro computed tomography analysis of abrasivity of toothpaste tablets compared to conventional toothpaste

PURPOSE

To evaluate with microCT dentin and enamel abrasion depth caused by toothpaste tablets when compared to conventional toothpastes.

METHODS

Dentin (N= 64) and enamel blocks (N=64) were randomized into four experimental groups of 16 specimens each for dentin and enamel. CP: Colgate Cavity Protection, served as the low abrasive toothpaste; AW: Colgate Total Advanced Whitening was used to represent a highly abrasive toothpaste. Two different types of toothpaste tablets were used. DT: Denttabs and BT: Bite tabs. To prepare the slurries, 40 mL of water was added to 25 g of each toothpaste and 4.4 g of each toothpaste tab. Blocks were brushed for a total of 10,000 and 40,000 strokes for dentin and enamel, respectively following ISO standard 11609. On completion of brushing, specimens were scanned with a microCT system. Tomographic 3D reconstruction followed by abrasion depths measurements were performed. Kruskal-Wallis procedure tested abrasion depths among the different groups. Tests of hypotheses were two-sided with an alpha level at 0.05.

RESULTS

There was a statistically significant difference in dentin abrasion depth among the groups (P< 0.001). The mean dentin/enamel abrasion depths in microns were 25.3/4.4, 36.8/4.4, 66.8/3.0, and 230.3/15.5 for DT, BT, CP, and AW respectively. Dentin and enamel abrasion depth of AW was the highest and was different from all other groups after multiple comparisons (P< 0.05).

CLINICAL SIGNIFICANCE

Dentin abrasivity of toothpaste tabs is negligible as determined with microCT.

A randomized, blinded, clinical investigation of breath odor reduction efficacy of a stabilized chlorine-dioxide containing flavored mouthwash

PURPOSE

To evaluate the efficacy of a flavored, non-fluoridated, alcohol-free mouthwash containing 0.1% chlorine dioxide in reducing oral malodor.

METHODS

This was a randomized, 8-week, single site, double blind, crossover design with a 2-week washout period between crossover phases. Fifty subjects with clinically diagnosed intrinsic oral malodor were enrolled according to inclusion/exclusion criteria and randomized to one of two groups. Washout period initiated at end of Phase I and crossover design implemented prior to Phase II. Calibration for organoleptic judges performed at baseline for both phases.

RESULTS

48 subjects completed the study. No significant differences in intensity scores at baseline were found for both groups during both phases (P> 0.05). Within group comparisons for placebo revealed no significant differences with organoleptic intensity scores for all visits during both phases (P> 0.05). During Phase I, the mean changes in organoleptic scores for the test group were significantly different from the baseline at each visit: Weeks 1 to 3 (P< 0.05). After crossover, significant differences were found for the last two visits: Weeks 7 and 8 (P< 0.05). No adverse effects to oral tissues were observed or reported. This product is safe to use for up to 3 weeks and resulted in a decrease in oral malodor.

CLINICAL SIGNIFICANCE

Results suggested that twice-daily use of a 0.1% chlorine dioxide-containing flavored mouthwash, in conjunction with normal oral hygiene care, provided clinically relevant improvements in oral malodor for up to 3 weeks.

Enhancement of peripheral seal of medical face masks using a 3-dimensional-printed custom frame

Background

During the COVID-19 pandemic, American Society for Testing and Materials level 3 and level 2 medical face masks (MFMs) have been used for most health care workers and even for the first responders owing to a shortage of N95 respirators. However, the MFMs lack effective peripheral seal, leading to concerns about their adequacy to block aerosol exposure for proper protection. The purpose of this study was to evaluate the peripheral seal of level 3 and level 2 MFMs with a 3-dimensional (3D-) printed custom frame.

Methods

Level 3 and level 2 MFMs were tested on 10 participants with and without a 3D-printed custom frame; the efficiency of mask peripheral seal was determined by means of quantitative fit testing using a PortaCount Fit Tester based on ambient aerosol condensation nuclei counter protocol.

Results

The 3D-printed custom frame significantly improved the peripheral seal of both level 3 and level 2 MFMs compared with the masks alone (P < .001). In addition, both level 3 and level 2 MFMs with the 3D-printed custom frame met the quantitative fit testing standard specified for N95 respirators.

Practical Implications

The 3D-printed custom frame over level 3 and level 2 MFMs can offer enhanced peripheral reduction of aerosols when using collapsible masks. With the shortage of N95 respirators, using the 3D-printed custom frame over a level 3 or level 2 MFM is considered a practical alternative to dental professionals.

Heat and Sound Generation During Implant Osteotomy When Using Different Types of Drills in Artificial and Bovine Bone Blocks

The purpose of this study was to compare heat and sound generated during implant osteotomy when different types of drill were used in artificial bone and bovine bone blocks. A total of 80 implant osteotomies were formed using 4 implant drilling systems; N1 (OsseoShaper) (Nobel), NobelActive (Nobel), V3 (MIS) and BLX (Straumann) in both artificial bone and bovine bone blocks. Thermocouple probes were used to record temperature change at the depths of 5.0 mm and 13.0 mm of each implant osteotomy formed by the final drill. In addition, thermographic images, drilling sound, and drilling time were recorded and evaluated. Statistical analyses were performed at α = 0.05. The mean temperature changes as recorded by thermocouple probes and thermocamera were significantly lower in OsseoShaper than most other drill-bone combinations (p < .05). The mean drilling times and sound generation for OsseoShaper were significantly higher and lower than most other drill-bone combinations (p < .05), respectively. Minimal heat and sound generation can be expected when implant osteotomies are performed using Osseoshaper at a low rotational speed (50 rpm) even without irrigation. However, extended drilling time is required.

Participation in pulmonary hypertension support group improves patient-reported health quality outcomes: a patient and caregiver survey

Support group participation has been shown to be effective in many chronic medical conditions. The evidence for integrating support group into pulmonary hypertension care and its effect on quality of life, physical and psychological well-being is limited. We sought to assess the effect of support group participation on quality of life in patients diagnosed with pulmonary hypertension and their caregivers. The emPHasis-10 questionnaire (a tool validated for quality of life assessment in pulmonary hypertension) was used to evaluate the effect of support group participation. Additional demographic and health-related quality measures were examined. Results showed that 165 subjects were enrolled in the study; 122 (74.4%) were patients with pulmonary hypertension, 41 (25.0%) were their caregivers, and 2 (0.02%) did not respond. The cohort was predominantly female (n = 128, 78%), Caucasian (n = 10, 61%), and the principal self-reported classification of pulmonary hypertension was World Health Organization Group 1 (n = 85, 51.8%) and the self-reported New York Heart Association Functional Class was II and III (n = 43, 57.3%). Most participants (n = 118, 71.5%) attended support groups and of them, a majority (n = 107, 90.6%) stated it helped them. There was no difference in quality of life as assessed by emPHasis-10 scores with support group participation (median score 30 vs 32, p = 0.387). There was self-reported improvement in understanding condition better including procedures such as right heart catheterization, medication compliance, and confidence in self-care (p < 0.05). Using multivariate logistic regression, baseline variables that were independently associated with emPHasis-10 scores for the entire cohort included knowledge of New York Heart Association Functional Class (odds ratio: 1.919, 95% CI: 1.004–3.67, p = 0.04) and greater distance traveled to visit pulmonary hypertension physician (odds ratio: 1.391, 95% CI: 0.998--1.94, p = 0.05). In conclusion, support group participation does not improve quality of life as assessed by emPHasis-10 scores but improves other meaningful health-related quality outcomes.

Platelet and neutrophil responses to Porphyromonas gingivalis in human whole blood

Porphyromonas gingivalis is a causative agent for periodontal disease. Binding of platelets to this gram-negative anaerobe can regulate host hemostatic (thrombus forming) and immune (neutrophil interacting) responses during bacterial infection. Additionally, in response to bacterial pathogens neutrophils can release their DNA, forming highly prothrombotic neutrophil extracellular traps (NETs), which then further enhance platelet responses. This study evaluates the role of P. gingivalis on platelet expression of CD62P, platelet-neutrophil interactions, and labeled neutrophil-associated DNA. Human whole blood was preincubated with varying P. gingivalis concentrations, with or without subsequent addition of adenosine diphosphate (ADP). Flow cytometry was employed to measure platelet expression of CD62P using PerCP-anti-CD61 and PE-anti-CD62P, platelet-neutrophil interactions using PerCP-anti-CD61 and FITC-anti-CD16, and the release of neutrophil DNA using FITC-anti-CD16 and Sytox Blue labeling. Preincubation with a high (6.25 × 10⁶  CFU/mL) level of P. gingivalis significantly increased platelet expression of CD62P in ADP treated and untreated whole blood. In addition, platelet-neutrophil interactions were significantly increased after ADP stimulation, following 5-22 min preincubation of blood with high P. gingivalis CFU. However, in the absence of added ADP, platelet-neutrophil interactions increased in a manner dependent on the preincubation time with P. gingivalis. Moreover, after ADP addition, 16 min preincubation of whole blood with P. gingivalis led to increased labeling of neutrophil-associated DNA. Taken together, the results suggest that the presence of P. gingivalis alters platelet and neutrophil responses to increase platelet activation, platelet interactions with neutrophils, and the level of neutrophil antimicrobial NETs.

Oral health knowledge and oral health related quality of life of older adults

OBJECTIVE

To assess the relationship between oral health knowledge and oral health related quality of life among older adults with different ethnicities living in San Bernardino County, California. There is a gap in oral health knowledge (OHK) and how it relates to perceived oral health related quality of life. Thus, there is a need to assess OHK as a component of oral health literacy and identify areas in which knowledge gaps exit to develop educational strategies that address the need of the elderly population.

MATERIALS AND METHODS

The study was a cross-sectional study that included adults 65 years and older using a validated "Comprehensive Measure of Oral Health Knowledge" (CMOHK) and an "Oral Health Profile Index" (OHIP-14). Odds ratios were conducted to determine the factors associated with OHK.

RESULTS

Mean OHK score were 16.8, 14.6, and 8.9 for Caucasian, Asian, and Hispanics, respectively. "Poor" OHK was significantly associated with participants over the age of 75 years (OR = 1.9; 95% CI: 1.15-3.16), high school education or less (OR = 10.8; 95% CI: 5.92-19.84), minority ethnicity (OR = 7.3; 95% CI: 4.27-12.61), income less than $25,000 (OR = 10.7; 95% CI: 5.92-19.26), and reading ability less than "Excellent" (OR = 7.27; 95% CI: 4.35-12.14). Mean OHIP-Severity scores were 7.4, 12.5, and 24.4 for Caucasian, Asian, and Hispanics, respectively. Respondents with Poor OHK were 5.17 times more likely to be identified with high levels of severity (Severity >10).

CONCLUSION

It is imperative to develop communication strategies to inform older adults on oral health knowledge that provide equal opportunities for all ethnicities.

Dental and Dental Hygiene Students' Knowledge and Perception on Fluoride Use in Dentistry

AIM

The 75th anniversary of community water fluoridation in the United States was celebrated in 2020. However, there are studies that stimulate polarized discussion over the use of fluoride in dentistry. The purpose of this study was to evaluate dental and dental hygiene students' knowledge and perception of fluoride use in dentistry.

MATERIALS AND METHODS

A survey was conducted to gauge participant's knowledge and perception of fluoride and their opinion on the need for developing viable alternatives to fluoride. An Institutional Review Board (IRB# 5190496) application was filed and approved. A hard copy survey was distributed to all student classes at Loma Linda University School of Dentistry (U.S.) between January 13, 2020, and February 5, 2020. Descriptive data were compiled and analyzed. Knowledge-based questions were compared using Kruskal-Wallis procedure to evaluate correct percentage among different classes. Perception questions were analyzed using a Likert scale and also a Chi-squared test. All tests were two-sided with α at 0.05.

RESULTS

Out of 482 students, 282 students responded (58.5%). The mean of correct responses for knowledge ranged from 49 to 69%. There was a statistically significant difference among the classes. Overall the perception of the use of fluoride in dentistry was positive, and it changed with exposure to lectures on fluoride over the years.

CONCLUSION

There was a correlation between knowledge and the perception of the use of fluoride in dentistry, indicating the importance of adequate delivery of didactic teaching on knowledge of fluoride to dental and dental hygiene students.

CLINICAL SIGNIFICANCE

The oral healthcare provider plays a pivotal role in communicating pertinent information on the benefits of fluoride in preventing dental caries to the general public, prompting adequate delivery of didactic teaching on this topic in dental education.

Three-dimensional nonlinear prediction of tooth movement from the force system and root morphology

OBJECTIVES

To determine the different impact of moment-to-force ratio (M:F) variation for each tooth and spatial plane and to develop a mathematical model to predict the orthodontic movement for every tooth.

MATERIALS AND METHODS

Two full sets of teeth were obtained combining cone-beam computed tomography (CBCT) and optical scans for two patients. Subsequently, a finite element analysis was performed for 510 different force systems for each tooth to evaluate the centers of rotation.

RESULTS

The center of CROT locations were analyzed, showing that the M:F effect was related to the spatial plane on which the moment was applied, to the force direction, and to the tooth morphology. The tooth dimensions on each plane were mathematically used to derive their influence on the tooth movement.

CONCLUSION

This study established the basis for an orthodontist to determine how the teeth move and their axes of resistance, depending on their morphology alone. The movement is controlled by a parameter (k), which depends on tooth dimensions and force system features. The k for a tooth can be calculated using a CBCT and a specific set of covariates.

Platelet plug formation in whole blood is enhanced in the presence of Porphyromonas gingivalis

Porphyromonas gingivalis is a gram-negative anaerobic bacterium and an etiologic agent of adult periodontitis. By inducing a dysbiotic state within the host microbiota it contributes to a chronic inflammatory environment in the oral cavity. Under some circumstances, the oral bacteria may gain access to systemic circulation. While the most widely recognized function of platelets is to reduce hemorrhage in case of vascular damage, it is known that platelets are also involved in the hematologic responses to bacterial infections. Some pathogenic bacteria can interact with platelets, triggering their activation and aggregation. The aim of this study was to assess platelet responses to the presence of P. gingivalis in whole blood. Human whole blood was pretreated with P. gingivalis and then platelet plug formation was measured under high shear conditions using the PFA-100. In the presence of P. gingivalis, time for a platelet plug to occlude the aperture in the collagen/ADP cartridge was shortened in a manner dependent on bacterial concentration and the duration of bacterial preincubation of blood. P. gingivalis enhances thrombus forming potential of platelets in whole blood.

Measurement of erosion depth using microcomputed tomography and light microscopy

Tooth-erosion is the surface loss of dental hard tissue mostly associated with an acid attack. The aim was to compare dentin and enamel erosion depth measurements using micro-computed tomography (microCT) and light microscopy (LM). Enamel/dentin blocks were prepared from caries-free human molar-teeth (N = 12). Teeth were sectioned to a rectangular shape of 4 × 4 × 6 mm. Specimens were treated with water (NC) or 1.0% citric-acid solution (PC). After treatment, specimens were scanned with micro-computed tomography. On completion, specimens were sectioned and observed under a light-microscope. Lesion depth was observed with 10× magnification and images transferred to Simpleware software. Vertical distance from lesion surface to bottom was measured. Pearson correlation test was used to evaluate correlation and Wilcoxon Signed Rank test to evaluate differences in the two-analysis methods. Mean enamel erosion depth was 0.63 and 38.38 μm (microCT) and 0.54 and 39.43 μm (LM) for NC and PC, respectively. Dentin erosion depth was 0.72 and 48.05 μm (microCT) and 0.56 and 49.92 μm (LM) for NC and PC, respectively. There was a significant correlation between the two-analysis methods (r = 0.998; p < .001). No statistically significant difference in results were obtained when microCT and LM were compared (p = .584). This results obtained from the current study suggested that erosion depth measurements made using microCT and LM yielded comparable results. The microCT method is preferred if the conservation of specimens is desired.

PSMA-targeted Radiotracers versus 18F Fluciclovine for the Detection of Prostate Cancer Biochemical Recurrence after Definitive Therapy: A Systematic Review and Meta-Analysis

Background National guidelines endorse fluorine 18 (¹⁸F) fluciclovine PET/CT for the detection of prostate cancer (PCa) in men with biochemically recurrent PCa. The comparative performance between fluciclovine and gallium 68 or ¹⁸F prostate-specific membrane antigen (PSMA) PET/CT, a newer examination, is unclear. Purpose To compare the detection of biochemical recurrence using fluciclovine versus PSMA-targeted radiotracers in patients with a prostate-specific antigen (PSA) level less than 2 ng/mL. Materials and Methods With use of the Preferred Reporting Items for a Systematic Review and Meta-Analysis of Diagnostic Test Accuracy, or PRISMA-DTA, guidelines, a systematic review of PubMed and EMBASE databases between 2012 and 2019 was performed. Studies of fluciclovine PET/CT or PSMA PET/CT in biochemical recurrence were identified. PSA levels, clinical data, and reference standards were obtained when available. A random-effects model was applied to pooled estimates and 95% confidence intervals (CIs) around the prevalence of a positive examination, stratified according to PSA tier. Results Quantitative analysis included 482 patients (median age, 67 years; interquartile range, 67-67 years) in six fluciclovine studies and 3217 patients (median age, 68 years; interquartile range, 67-70 years) in 38 PSMA studies. Pooled detection rates for PSMA and fluciclovine were 45% (95% CI: 38%, 52%) and 37% (95% CI: 25%, 49%), respectively, for a PSA level less than 0.5 ng/mL (P = .46); 59% (95% CI: 52%, 66%) and 48% (95% CI: 34%, 61%) for a PSA level of 0.5-0.9 ng/mL (P = .19); and 80% (95% CI: 75%, 85%) and 62% (95% CI: 54%, 70%) for a PSA level of 1.0-1.9 ng/mL (P = .01). A reference standard was positive in 703 of 735 patients (96%) in the PSMA cohort and 247of 256 (97%) in the fluciclovine cohort. Conclusion Patient-level detection rates for biochemically recurrent prostate cancer were greater for prostate-specific membrane antigen-targeted radiotracers than fluciclovine for prostate specific antigen levels of 1.0-1.9 ng/mL. © RSNA, 2020 Online supplemental material is available for this article.

Systematic review of in vitro studies evaluating tooth bleaching efficacy

PURPOSE

To review and assess the literature on in vitro studies evaluating tooth bleaching efficacy considering the use of a negative control, type of tooth substrate, storage medium, color evaluation methods, and evaluation time points.

METHODS

The following databases were searched: PubMed (MEDLINE), Web of Science. Search used Medical Subject Headings (MeSH) in PubMed in addition to free text. The following limits were applied: English, articles published between January 1989 and October 2017. Additional free text key terms included: in vitro, tooth bleaching, placebo, negative control, overall CIELAB color change (ΔE*ab), change in shade guide units (ΔSGU), tooth color stabilization, evaluation time points, bovine teeth, and staining. Search was repeated in Web of Science but no additional articles were identified. A total of 11 studies were included for qualitative and quantitative analysis.

RESULTS

The meta-analysis of nine included studies that reported ΔE*ab values, revealed that the NC statistically exceeded the perceptibility threshold (PT) of 1.2 (P< 0.05). The estimate was 2.872 with lower and upper bounds of 1.955 and 3.790, respectively.

CLINICAL SIGNIFICANCE

Randomized controlled trials are gold standards to evaluate bleaching efficacy of different materials. However, in vitro studies offer a way to screen for potential bleaching efficacy. It is vital to determine an appropriate cut-off value for determining bleaching efficacy in vitro and further apply for clinical relevance.

Relationship Between Body Mass Index and Dental Development in a Contemporary Pediatric Population in the United States

Purpose: To determine if there is a positive correlation between increased body mass index (BMI) and dental development in children.<br/>Methods: The records of 500 six- to 13-year-old children were reviewed, and 250 were included in the study. BMI was calculated for each patient. Panoramic radiographs were evaluated, and dental age was estimated using Cameriere's formula. Delta values (dental age, chronological age) were analyzed using the Kruskal-Wallis test. All tests of hypotheses were two-sided at an alpha level of 0.05.<br/>Results: A statistically significant difference in delta was observed among different BMI categories (P <0.001). Larger deltas were observed for obese patients compared to normal weight patients (P = 0.027) and underweight patients (P = 0.012). Prepubertal patients were observed to have larger deltas than pubertal patients (P < 0.001). Differences between sexes were not significant (P = 0.930).<br/>Conclusion: Obese children were more advanced dentally than normal or under-weight children. Older children were more dentally advanced than their chronological age when compared to younger children. As children grew older, the difference between dental age and chronological age decreased.

Effect of Bleaching Gel Viscosity on Tooth Whitening Efficacy and Pulp Chamber Penetration: An In Vitro Study

Objectives:

Whitening efficacy has been related to hydrogen peroxide (HP) diffusion into tooth structure. However, little information is available relating rheological properties to whitening efficacy. The purpose was to evaluate the whitening efficacy and HP penetration level of a 10% HP gel at three different viscosities and to compare them to a strip delivery system.

Methods and Materials:

Extracted molars (n=120) were randomly assigned into five groups (n=24/ group): NC_MED (negative control; median): medium viscosity gel without HP; LOW: 10% HP gel (low viscosity experimental gel, Ultradent Products Inc); MED: 10% HP gel (medium viscosity experimental gel, Ultradent); HIGH: 10% HP gel (high viscosity gel, Ultradent); and CWS: Crest 3D Whitestrips 1-Hour Express (Procter & Gamble). All teeth were subjected to five 60-minute whitening sessions. Instrumental color measurements were performed at baseline (T0), and 1-day after each application (T1-T5), and 1-month after whitening (T6). HP penetration was estimated with leucocrystal violet and horseradish peroxidase. A Kruskal-Wallis test and post hoc Bonferroni test were performed to assess the difference in tooth color change and HP penetration among the groups (α=0.05).

Results:

Hydrogen peroxide penetration levels and overall color changes at T6 were 0.24 μg/mL / 2.80; 0.48 μg/mL / 8.48; 0.44 μg/mL / 7.72; 0.35 μg/mL / 8.49; 0.36 μg/mL / 7.30 for groups NC, LOW, MED, HIGH, and CWS, respectively. There was a significant difference for HP penetration, while there was no significant difference among the four experimental groups for tooth color change.

Conclusion:

Rheological properties should be considered when developing new whitening formulations.

Evidence-Based Practice Knowledge, Attitude, Access and Confidence: A comparison of dental hygiene and dental students

Purpose: The purpose of this study was to evaluate whether current educational strategies at a dental institution in the United States made a difference in dental hygiene (DNHY) and dental students' (D3) learning outcomes in the four domains of evidence-based practice (EBP), knowledge, attitude, accessing evidence, and confidence (KACE), following a 12-week research design course.Methods: All participants DNHY (n=19) and D3 (n=96) enrolled in the research design course at Loma Linda University completed a paper KACE survey distributed on the first day of class. Students completed the KACE survey once more at the end of the 12-week course. Pre- and post-survey results were compared both within and between the DNHY and D3 student groups to identify the learning outcomes in the four domains of EBP; knowledge, attitude, accessing evidence, and confidence in EBP. Descriptive statistics were conducted to profile all variables in the study; the level of significance was set at α=0.05.Results: All DNHY students (n=19) completed the pre and post KACE surveys; of the D3 (n=96) students enrolled in the course 82% (n=79) competed the post-survey. Comparison of the survey results showed that both DNHY and D3 students demonstrated statistically significant increases in their level of knowledge and attitude (p < 0.05) towards EBP. In the attitude domain, DNHY students indicated more positive attitudes towards EBP (p < 0.001) than their D3 student cohorts. Neither group demonstrated significant changes in confidence in applying EBP (p > 0.05).Conclusion: DNHY and D3 students increased their knowledge and developed more positive attitudes towards EBP following a 12-week research design course. Study results identify improvement areas for EBP knowledge acquisition including determining levels of evidence, analysis of study results, and evaluating the appropriateness of research study designs through the use of validated EBP survey instrument.

The Influence of Adalimumab on the Healing of Apical Periodontitis in Ferrets

INTRODUCTION

Given the increasing use of anti-tumor necrosis factor α (anti-TNFα) biologic medications, and their interferences with the immune-inflammatory response, this study evaluated the effect of adalimumab (anti-TNFα), on healing and healing time of apical periodontitis (AP) in ferrets.

METHODS

Twelve male ferrets received cone beam computed tomography of the jaws at baseline health (T0); AP confirmation (T1); and 30 (T2), 60 (T3), and 90 (T4) days after root canal treatment (RCT) to monitor healing. All animals had AP induced in the canines; 3 ferrets (12 teeth) provided the positive controls for the histologic evaluation; 9 ferrets were randomly divided into 3 treatment groups with 12 teeth each in the following manner: Systemic: conventional RCT and systemic anti-TNFα; Local: RCT and periapical administration of anti-TNFα before canal obturation; conventional RCT only (control). Two calibrated radiologists assessed the cone beam computed tomography images independently and blindly for AP identification and quantification. Rank-based analysis of covariance was used for statistical analysis of lesion size.

RESULTS

AP was induced in all teeth. Following RCT, all AP lesions in the 3 groups showed a significant reduction in size. Specific pairwise comparisons of the related samples (Friedman's 2-way analysis of variance by ranks within each group) demonstrated a decreasing trend in lesion size with healing time in all 3 groups, most pronounced for local group (local adalimumab). No statistical difference was noticed between groups.

CONCLUSIONS

Both systemic and local anti-TNFα did not hinder AP healing in this animal model and a faster healing response may also be anticipated. These findings encourage follow-up studies with larger sample sizes.

Effect of Light-Activated Tooth Whitening on Color Change Relative to Color of Artificially Stained Teeth

PURPOSE

There is still controversy as to the efficacy of light activation used in tooth whitening. The purpose of this study was to evaluate the effect of light activation on tooth color change relative to the artificial dye color.

MATERIALS AND METHODS

Extracted human third molars (160) were randomly distributed into eight groups of 20 specimens each based on artificial staining and use of light activation. All groups received three 45-minute sessions of in-office whitening at 3-day intervals. Color measurements were performed with an intraoral spectrophotometer at baseline prior to staining (T0), after artificial staining (T1), 1-day--(T2), and 1-week--(T3) post-whitening. Color differences were calculated relative to after artificial staining color parameters (L*1, a*1, b*1) with the use of a software analysis program enabling synchronization of two images.

RESULTS

Within the same staining groups, the light-activated samples exhibited a greater color change than their nonlight-activated counterparts. However, only in the case of the yellow-stained samples at 1-day post-whitening was there a significant difference between the nonlight-activated and light-activated groups (Tukey's post hoc multiple comparison test for pairwise comparisons, p < 0.05).

CONCLUSIONS

Light activation is a valid method for enhancing the efficacy of tooth whitening with respect to overall color change and works best with yellow stains.

CLINICAL SIGNIFICANCE

Light activation is a valid method for enhancing the efficacy of tooth whitening with respect to overall color change and works best with yellow stains.

Morphometric facial analysis: a methodology to create lateral facial images

INTRODUCTION

Currently, the majority of research in facial analysis using computational morphing methods focuses exclusively on analysis of frontal facial projections. Lateral facial morphing analysis has not been extensively investigated, and landmark features critical to specify registry points are unknown. This study aims to (1) determine the quantity of registry points (RP) required to create realistic lateral faces and (2) determine key facial registry point landmarks required to create synthetic lateral faces.

METHOD

36 synthetic lateral faces with a 50 to 250 RP were created to determine the ideal quantity of RP to create a realistic lateral image; ear, eyebrow, eye, nose, lips, hairline, facial outline, and overall outline were evaluated by an expert panel of seven evaluators using a 1 to 5 point Lickert scale rating system.

RESULT

ANOVA single-variable analyses revealed significant differences when comparing templates of 200 and 250 RP with 50 and 100 RP templates (p < 0.05). Furthermore, analysis of all key landmark areas of the face indicated significant differences between different registry points except for 200 and 250 registry point markers. Kruskal-Wallis statistical analysis revealed the landmarks varied significantly from 50 to 200 RP,but had no significance with 200 and 250 RP.

CONCLUSION

The most ideal quantity of RP used for the creation of realistic lateral faces was in the range of 200 RP. Defined lateral facial registry point landmarks generated successful realistic faces.

Efficacy of Do-It-Yourself Whitening as Compared to Conventional Tooth Whitening Modalities: An In Vitro Study

Aim

To evaluate the efficacy of do-it-yourself (DIY) whitening as compared to conventional tooth whitening modalities using different shade assessment tools.

Methods and Materials

Extracted human molars (120) were randomly distributed to six groups (n=20). Whitening was performed according to manufacturer's directions for over-the-counter, dentist-dispensed for home use, and in-office whitening. DIY whitening consisted of a strawberry and baking soda mix. Additionally, negative and positive controls were used. Two evaluators used the Vita Classical (VC) and Vita Bleachedguide 3D-Master with interpolated numbers (BGi) for visual assessment at baseline and one-week, one-month, and three-month postwhitening. Instrumental measurements were performed with a spectrophotometer. Kruskal-Wallis procedure was used to assess color changes among groups and intraclass correlation (ICC) to evaluate agreement between evaluators.

Results

DIY exhibited lower color change (ΔSGUVC, ΔSGUBGi, ΔE*, where SGU = shade guide unit and E = overall color change) compared to other whitening groups at all time points (p&lt;0.05). ICC demonstrated very good agreement between evaluators with VC and BGi at each time point. Both shade guides were related with each other and strongly related to instrumental measurements (p&lt;0.05).

Conclusions

DIY whitening was the least effective whitening modality. Both VC and BGi are related with each other and have good correlation with instrumental measurements.

Effect of various tooth whitening modalities on microhardness, surface roughness and surface morphology of the enamel

The purpose of this study was to evaluate the effect of four whitening modalities on surface enamel as assessed with microhardness tester, profilometer, and scanning electron microscopy (SEM). Whitening was performed according to manufacturer's directions for over-the-counter (OTC), dentist dispensed for home use (HW) and in-office (OW) whitening. Do-it-yourself (DIY) whitening consisted of a strawberry and baking soda mix. Additionally, negative and positive controls were used. A total of 120 enamel specimens were used for microhardness testing at baseline and post-whitening. Following microhardness testing specimens were prepared for SEM observations. A total of 120 enamel specimens were used for surface roughness testing at baseline and post-whitening (n = 20 per group). Rank-based Analysis of Covariance was performed to compare microhardness and surface roughness changes. Tests of hypotheses were two-sided with α = 0.05. There was a significant difference in Knoop hardness changes (ΔKHN) among the groups (Kruskal-Wallis test, p < 0.0001). Significant hardness reduction was observed in the positive control and DIY group (p < 0.0001). Mean surface roughness changes (ΔRa) were significantly different among the groups (Kruskal-Wallis test, p < 0.0001). Surface roughness increased in the OTC group (p = 0.03) and in the positive control (p < 0.0001). The four whitening modalities-DIY, OTC, HW and OW induced minimal surface morphology changes when observed with SEM. It can be concluded that none of the four whitening modalities adversely affected enamel surface morphology. However, caution should be advised when using a DIY regimen as it may affect enamel microhardness and an OTC product as it has the potential to increase surface roughness.

Influence of Application Techniques on Contact Formation and Voids in Anterior Resin Composite Restorations

This study evaluated the influence of three different application techniques on contact formation and voids in anterior resin composite restorations. Artificial ivorine teeth were randomly assigned to three experimental groups, with 20 specimens in each group. One operator performed all restorations using the Teflon tape, pull-through, or bioclear matrix technique. The treatment time required for each restoration was recorded. An examiner blinded to the treatment group performed the visual evaluation of six criteria, including proper contact formation. The restored teeth were cut to yield a total of 180 sections for microscopic evaluation. The Kruskal-Wallis procedure was performed to evaluate the significance of treatment time, number of voids, percent porosity area, and void diameter. There were significant differences in treatment time among the three groups (p&lt;0.05). The bioclear matrix technique required the least time for the treatment of one diastema closure (p&lt;0.05). The Teflon tape technique resulted in proper contact formation in 80% of specimens, a rate that was significantly lower than that associated with the pull-through and bioclear matrix techniques (p&lt;0.05). Out of 540 imaging areas 160 images were free of voids. The number of voids and the percent porosity area were not significantly different among the three techniques (p&gt;0.05). However, the mean void diameter was greater with the bioclear matrix technique compared to the other two techniques (p&lt;0.05).

Evaluation of bleaching efficacy and erosion potential of four different over-the-counter bleaching products

PURPOSE

To evaluate the bleaching efficacy and erosion potential of various over-the-counter bleaching products following a test method specified in ISO 28399.

METHODS

Specimens were prepared from bovine molars, stained in tea solution, embedded and randomly assigned to six groups of 10 enamel and dentin specimens each. Color was assessed at baseline, 1 day and 1 month post-bleaching with the Vita Bleachedguide 3D Master shade guide. Surface roughness changes (deltaRa), determined by baseline and post-treatment values were measured with a profilometer. The negative (NC) and positive control (PC) was treated with grade 3 water and 1.0% citric acid, respectively. Over-the-counter products were used according to manufacturer's instructions. Brite Teeth Pro (BT), Natural White 5-Minute Whitening (NW), Luster Premium White (LP), and Crest 3D Whitestrips (WS) represented a brush-on-paint system, tray system, light-activated system and adhesive-strip system, respectively. Kruskal-Wallis procedure was used to compare surface roughness changes among groups. Color change was assessed with Friedman-test and stratified by hard tissue type with alpha= 0.05.

RESULTS

WS was the only group demonstrating color changes in enamel and dentin (P< 0.05). There were no differences in deltaRa for enamel and dentin among NC, BT, LP, and WS. NW showed increase in deltaRa in dentin (P< 0.05), while PC demonstrated an increase in deltaRa regardless of hard tissue type (P< 0.05).