Effectiveness and feasibility of utilizing E4D technology as a teaching tool in a preclinical dental education environment.

Recent efforts have been directed towards utilizing CAD/CAM technology in the education of future dentists. The purpose of this pilot study was to investigate the feasibility of implementing CAD/CAM technology in instruction on preparing a tooth for restoration. Students at one dental school were assigned access to CAD/CAM technology vs. traditional preparation methods in a randomized, crossover design. In a convenience sample of a second-year class, seventy-six of the seventy-nine students volunteered to participate, for a response rate of 96 percent. Two analyses were performed on this pilot data: a primary effectiveness analysis comparing students' competency exam scores by intervention group (intention-to-treat analysis) and a secondary efficacy analysis comparing competency exam scores among students who reported using CAD/CAM versus those who did not. The effectiveness analysis showed no difference in outcomes by intervention group assignment. While student survey results indicated interest in utilizing the technology, the actual utilization rate was much less than one might anticipate, yielding a sample size that limited statistical power. The secondary analysis demonstrated higher mean competency exam scores for students reporting use of CAD/CAM compared to those who did not use the technology, but these results did not reach statistical significance (p=0.075). Prior research has investigated the efficacy of CAD/CAM in a controlled educational trial, but this study adds to the literature by investigating student use of CAD/CAM in a real-world, self-study fashion. Further studies should investigate ways in which to increase student utilization of CAD/CAM and whether or not increased utilization, with a larger sample size, would yield significant outcomes.

Estimation of transpalatal nasalance during production of voiced stop consonants by noncleft speakers using an oral-nasal mask.

OBJECTIVE: Our objective was to estimate nasalance due to transpalatal transfer of acoustic energy during production of voiced stop consonants by noncleft speakers. We also determined the relationship between the transpalatal nasalance and fundamental frequency (F0) of the speakers. METHOD: Participants were 8 men and 10 women (mean age = 21.9 years, SD = 4.0) without cleft palate who produced voiced stop (/b d g/) and nasal (/m n eta/) consonants in syllables embedded in a carrier phrase. Participants also read the Zoo Passage. A divided OroNasal Nasality System mask was used to simultaneously obtain acoustic nasalance and airflow during production of the consonants. Both F0-derived and first formant (F1)-derived nasalance were computed. RESULTS: F0-derived and F1-derived peak nasalance across all speakers ranged from a low of 20% to a high of 80% during production of stop consonants. An estimate of error from the combined sources of transoral transfer of energy (5%) and acoustic crossover between microphones (15%) was no greater than 20%. Analysis of variance revealed no significant effects of the sex of the speakers for either F0-derived or F1-derived nasalance of stops. There was a significant effect of the place of stop production for F0-derived nasalance (p;th< .05). Nonsignificant but positive correlations were found between the F0 of the speakers and F0-derived (r = .25) and F1-derived (r = .45) nasalance. CONCLUSIONS: Transpalatal transfer of oral acoustic energy accounts for most nasalance obtained during production of voiced stop consonants by noncleft speakers. F1-derived nasalance appears to better reflect transpalatal effects. Clinical implications are discussed.