This study examined the reliability and predictive validity of a comprehensive, multidisciplinary objective structured clinical examination (OSCE) used to assess the transition from preclinical to clinical education in a dental school. The examination is administered prior to clinical training at the Columbia University College of Dental Medicine to assess student preparedness for patient care activity. The study population consisted of seventy-ive students in the Class of 2010 and seventy students in the Class of 2011. The total reliability of the exam was assessed by Cronbach's coeficient alpha. Using polynomial regression, the predictive validity of the examination was evaluated by correlating student scores on the OSCE with clinical performance as measured by successfully completed clinical procedures during the irst year of clinical training. Findings indicate a highly reliable exam (α=0.86 and α=0.80) with a moderately high correlation predicting future clinical performance (r=0.614, p<0.0001; r=0.540, p<0.0001) for the Classes of 2010 and 2011, respectively. The indings suggest that an OSCE can serve as a reliable and predictive assessment during the transition from preclinical to clinical education in the predoctoral dental curriculum.

The aim of this study was to evaluate the use of a local anesthesia (LA) simulation model in a facilitated small group setting before dental students administered an inferior alveolar nerve block (IANB) for the irst time. For this pilot study, 60 dental students transitioning from preclinical to clinical education were randomly assigned to either an experimental group (N=30) that participated in a small group session using the simulation model or a control group (N=30). After administering local anesthesia for the irst time, students in both groups were given questionnaires regarding levels of preparedness and conidence when administering an IANB and level of anesthesia effectiveness and pain when receiving an IANB. Students in the experimental group exhibited a positive difference on all six questions regarding preparedness and conidence when administering LA to another student. One of these six questions ("I was prepared in administering local anesthesia for the irst time") showed a statistically signiicant difference (p<0.05). Students who received LA from students who practiced on the simulation model also experienced fewer post-injection complications one day after receiving the IANB, including a statistically signiicant reduction in trismus. No statistically signiicant difference was found in level of effectiveness of the IANB or perceived levels of pain between the two groups. The results of this pilot study suggest that using a local anesthesia simulation model may be beneicial in increasing a dental student's level of comfort prior to administering local anesthesia for the irst time.Dr. Lee is a Resident,

The aim of this study was to examine student perceptions of the educational value of a comprehensive, multidisciplinary objective structured clinical examination (OSCE). The examination is administered after the second year of the curriculum, prior to the beginning of clinical training at the Columbia University College of Dental Medicine. The quantitative component of the study consisted of a survey administered to students who had taken the OSCE (N=78). Due to the ordinal level of data produced by the Likert-scale survey, statistical analysis was performed through calculation of the median and interquartile range (IQR). Overall, student perceptions of the educational value of the OSCE, as measured using a ive-point scale (1=strongly disagree to 5=strongly agree) were positive, demonstrating students' agreement that the exam required the ability to think critically and problem-solve (median=4, IQR=1), assessed clinically relevant skills (median=5, IQR=1), and was a learning experience (median=5, IQR=1). A statistically signiicant chi-square value (p<0.001) was found for all questions. The qualitative component consisted of phenomenological examination of student focus group interviews (N=15). Four main themes were identiied including that the OSCE was an authentic assessment that required integration and application of knowledge.

INTRODUCTION: Although the microbiome is altered in various esophageal diseases, there is no direct evidence for a link between the oral or esophageal microbiome and underlying esophageal tissue. Here, we aimed to address these gaps through use of an antimicrobial mouth rinse to modify the esophageal microbiome and tissue gene expression. METHODS: In this randomized controlled trial, patients scheduled to undergo endoscopy for clinical indications used chlorhexidine mouth rinse or no treatment for 2 weeks before endoscopy. Oral swabs and saliva were collected at baseline and at follow-up, and the esophagus was sampled on the day of endoscopy. The microbiome was analyzed by 16S rRNA gene sequencing, and esophageal tissue gene expression was ascertained by RNA-Seq. RESULTS: Twenty subjects were enrolled and included in the analyses. Within individuals, the oral and esophageal microbiome composition was significantly correlated. Chlorhexidine treatment associated with significant alterations to the relative abundance of several esophageal bacterial taxa, and to expression of genes in the esophagus including reductions in periostin, claudin-18, chemokines CXCL1 and CXCL13 , and several members of the tumor necrosis factor receptor superfamily. A taxon in genus Haemophilus in the esophagus also associated with significant changes in tissue gene expression. DISCUSSION: The oral and esophageal microbiomes are closely related within individuals, and esophageal microbiome alterations correlate with tissue gene expression changes. The esophageal microbiome may act as an important cofactor that influences pathogenesis and outcomes of diseases such as eosinophilic esophagitis, gastroesophageal reflux, and Barrett's esophagus.