The intrajudge reliability of the perceptual rating of cleft palate speech before and after pharyngeal flap surgery: the effect of judges and speech samples.

OBJECTIVE: In this pilot study, the reliabilities of the perceptual ratings of four types of speech samples by six judges, with and without expertise in evaluating cleft palate speech, were studied. DESIGN: Pre- and postoperative tape recordings of 15 patients with cleft lip and palate who had undergone a superiorly based pharyngeal flap operation were selected. Five speech-language pathologists and one oral and maxillofacial surgeon perceptually rated the following variables on separate 100-mm visual analog scales: hypernasality, audible nasal emission, intelligibility, misarticulations associated with velopharyngeal insufficiency, voice quality, and the presence or absence of hyponasality. These six variables were rated in four types of speech samples: reading of three sentences, repeating after the speech pathologist of three sentences, 10 sentences containing the aforementioned material, and the same 10 sentences in paired comparison. All speech samples were rerated after 3 months by the same judges. RESULTS: Judges differed largely in the range they used in their rating. Intrajudge reliability of .56 to .78 was found for ratings of hypernasality. No significant differences in intrajudge reliability were found for the ratings with the different types of speech samples. The intrajudge reliability of a judge with expertise was not necessarily higher than of a judge without this expertise. CONCLUSIONS: The improvement in speech is most reliably assessed with speech samples in paired comparison. A speech-language pathologist with expertise in evaluating cleft palate speech does not guarantee a high intrajudge reliability of the rating.     

Test anxiety. Relationship to academic and clinical performance in dental hygiene students

This study investigated the relationship of test anxiety, study skills, aptitude, and prior GPA to academic and clinical performance in junior and senior dental hygiene students. Eighty-nine volunteer subjects completed a test anxiety scale (TAS) and an effective study test (EST) at the beginning of the spring semester. Prior grade point average (GPA) and dental hygiene candidate aptitude (DHCAT) scores were obtained, and the relationships of all variables to spring GPA and spring clinic grade were analyzed. TAS showed significant, but weak, inverse relationships with prior GPA (r = -.24, p less than .05) and spring GPA (r = -.29, p less than .01). Verbal, science, and reading comprehension subscales of the DHCAT were significantly and moderately associated with spring GPA. In a hierarchical/stepwise regression analysis. TAS did not explain any of the variance in academic or clinical performance. Study skills explained 3% of the variance in spring GPA and 6% of the variance in spring clinic grade. Prior GPA was identified as the strongest predictor of academic performance in the dental hygiene program as it explained 44% of the variance in overall spring GPA. None of the variables studied emerged as a strong predictor of clinical performance.     

Learning curves: what do dental students learn from repeated practice of clinical procedures?

It is generally accepted that repetition of procedures is necessary to develop clinical skill in dentistry. Although there is a rich empirical research tradition in medicine establishing competency levels for new procedures, investigations of the shape of learning curves for clinical techniques are rare in dental education. Data were reviewed from three classes (n=465) of students at the University of the Pacific Arthur A. Dugoni School of Dentistry in seventeen clinical skills in five departments for which test case (independent performance) data were available. It was hypothesized that a learning curve would be observed with gradually rising scores as a function of amount of repeated test case work and general practice experience. Other factors, such as faculty ratings and clinical GPA, could be expected to modify this curve. No evidence was found that test case performance was affected by number of previous test cases, number of practice (ungraded) procedures previously completed, faculty ratings of technical skill in the discipline by quarter, faculty ratings of patient management and of clinical judgment competencies, overall clinical GPA, and performance on initial licensure examinations. The absence of a pattern showing that amount of prior experience improves clinical performance raises questions about the practice of setting "requirements" for graduation and challenges dental educators to better explain the presumed relationship between practice and performance and the validity of clinical evaluation of performance based exclusively on the objective technical quality of work samples. The literature on learning curves and on competency-based education offer alternative insights into what students are actually learning but schools are failing to measure in the clinical experience.     

Do traditional techniques produce better conventional complete dentures than simplified techniques?

OBJECTIVES: To compare the quality of conventional complete dentures fabricated with two different techniques. A randomized controlled clinical trial was conducted to compare traditional (T) and simplified (S) methods of making complete conventional dentures on patients' ratings of satisfaction, comfort and function at 3 and 6 months following delivery. The quality of the prostheses was rated by prosthodontists at 6 months. MATERIALS AND METHODS: One hundred twenty-two male and female edentulous individuals, aged 45-75 years, were randomly allocated into groups that received dentures made with either T or S methods. Following delivery, patients' ratings of several denture-related factors were measured using 100mm visual analogue scales, and denture quality was assessed by blinded prosthodontists using ratings on a validated quantitative scale. RESULTS: There were no significant differences between the two groups in patient ratings for overall satisfaction (3 months: mean T = 83 mm, mean S = 83 mm, P = 0.97; 6 months: mean T = 79 mm, mean S = 79 mm, P = 0.96) or in prosthodontists' ratings of denture quality (T = 66, S = 63; P = 0.38). CONCLUSION: These results show that the quality of complete dentures does not suffer when manufacturing techniques are simplified to save time and materials. Dental educators should consider these findings when re-designing prosthodontic training programs.     

Relationship between prosthodontic evaluation and patient ratings of mandibular conventional and implant prostheses

PURPOSE: The purpose of this study was to compare clinicians' ratings of the state of oral tissues and their satisfaction with treatment to edentulous patients' ratings of treatment success after provision of mandibular implant overdentures or conventional dentures. MATERIALS AND METHODS: Sixty subjects randomly received either mandibular overdentures retained by two implants (n = 30) or new conventional mandibular complete dentures (n = 30). All were given new conventional maxillary dentures. Baseline measures included clinical evaluation of the oral soft and hard tissues. Patients rated their general satisfaction before and after treatment, as well as their satisfaction with stability, speech, and esthetics on visual analogue scales. The treating prosthodontist rated the dentures for the same categories. Patient and clinician ratings were compared using correlations, t tests, and linear regression. RESULTS: None of the clinical variables were significantly correlated with patient satisfaction before or after treatment. The prosthodontist rated mandibular implant overdentures significantly better than conventional dentures regarding general satisfaction, stability, speech, and esthetics. Implant overdentures were also easier to fabricate (P < .0001). The prosthodontists' scores were not significantly correlated with patient scores for any question. CONCLUSION: Clinicians' assessments of the quality of denture-supporting tissues are poor predictors of patient satisfaction with mandibular implant or conventional prostheses. Prosthodontists and patients both rate mandibular implant overdentures as significantly superior to conventional dentures, but patients and clinicians do not usually agree when evaluating individual prostheses.     

Problem-based learning versus a traditional educational methodology: a comparison of preclinical and clinical periodontics performance

To evaluate efficacy of a problem-based learning (PBL) pedagogy in preclinical and clinical teaching, test scores of 234 undergraduate dental students from the conventionally taught classes of 2003 and 2004 were compared with scores of 274 dental students from the PBL classes of 2005 and 2006. Although the groups' means were close together, t-test analysis of scores revealed that PBL students performed significantly better than traditional (TRAD) students on midterm (p=.0001) and final (p=.015) examinations taken on student partner/mock patients. ANOVA comparing the classes with each other showed significant differences for the midterm and final, but not for the clinical examination. Further multiple comparison tests (Tukey HSD) for the midterm and final revealed that differences specifically reflected superior performance of PBL classes against one of the TRAD classes (2004). There was no difference in performance between PBL (n=134) and TRAD (n=233) students on examinations taken with actual clinical patients who were undergoing nonsurgical periodontal treatment. Over a two-year period, PBL students rated their program instructors at a mean of 4.41 on a Likert-type scale of 1 (not helpful) to 5 (outstanding). The program provides a PBL model for teaching preclinical and clinical skills supported by a four-year evaluation of manual skills outcomes.     

Preparation course for Part I of the National Dental Boards: lessons learned

Student performance on national board examinations is the predominant litmus test for successful programs in health science education. Many different strategies have been used to increase passing rates among students. The objectives of this study were to investigate the influence of a voluntary eighteen-hour National Board Dental Examination Part I (NBDE Part I) preparation course on student performance on the NBDE Part I and to assess students' perspectives on the preparation course. Students' perspectives were obtained through a questionnaire and focus groups. There were significant associations between the students' GPA and the overall examination score and between the course grades corresponding with each section and the section scores. Students attending sessions devoted to specific NBDE subject areas did not obtain significantly better scores for that subject area than nonattending students. Also, the students did not obtain significantly better overall scores for NBDE Part I than in previous years when a preparation course was not conducted. Students most frequently rated the Dental Deck's NBDE Part I Cards as the most helpful study aid, followed by old NBDE Part I tests. The most frequent student rating for most of the presentations was "somewhat helpful," while the most frequent rating for resources placed on Blackboard such as tables and summary material was "helpful." Based upon the findings, we recommended discontinuation of the classroom presentation portion of the board preparation course.     

Retrospective study of five-year clinical performance of direct composite restorations using a self-etching primer adhesive system

This study was conducted to assess the five-year clinical performance of composite restorations using a self-etching primer adhesive system, Clearfil Liner Bond II. Restorations were rated using the following scale: A--Good; B--Clinically acceptable; C--Clinically unacceptable; or D--Already replaced. The ratings were analyzed using Freedman's test (p=0.01) and Steel-Dwass test (p=0.05). A total of 83 restorations from 36 patients were identified from treatment records. Twenty-six restorations (31.3%) presented A rating and 36 restorations (43.4%) were clinically acceptable (B rating), while five (6.0%) received C rating and 16 (19.3%) had already been replaced (D rating). The mean survival rate of serviceable restorations (i.e., combined A and B ratings) after five years was 74.7%. It was found that cavity form, including cavity size, and occlusal contact seemed to influence longevity.     

Evaluation of tooth preparations – A comparative study between faculty members and pre‐clinical students

Introduction: Preparation of teeth is a basic technique for dental treatment and plays an essential role in pre‐clinical education. The purpose of this study was to evaluate whether undergraduate students’ evaluations of prepared teeth were consistent with faculty assessments and correlated with students’ performance in test preparations. Materials and methods: Thirty four of 52 dental students having attended a pre‐clinical course on basic prosthodontic topics including tooth preparation volunteered to participate in this study. The students were given 10 casts each containing one tooth with an intentionally applied preparation fault of a certain type prepared by an experienced clinician. The students were asked to mark on a list the fault type found in every tooth. The association of students’ ratings with their performance during the course was analysed by means of a contingency table, and a generalised linear model was used to compare students’ and faculty ratings (α = 0.05). Results: No significant difference between students’ and faculty ratings could be found by analysis of deviance (P = 0.953). Significant deviations of fault detection probabilities from their group mean were found for six of ten fault types. No significant association between students’ performance in test preparations and students ratings could be found (P = 0.564). Discussion: It was possible to achieve a level of calibration within the group of students, which was comparable to that in the group of faculty members. Conclusions: Calibration of both students and examiners remains to be an issue with the teaching concepts applied in this study.     

Clinical Acceptability of Crown Margins Versus Marginal Gaps as Determined by Pre-Doctoral Students and Prosthodontists

PURPOSE: Marginal integrity is a very important element in evaluating a restoration; however, there is no agreement in definition of a clinically acceptable margin. The purpose of this investigation was to examine margin acceptability using an explorer versus the actual marginal gap widths at four locations on uncemented crowns on three extracted teeth using both predoctoral students and prosthodontists as evaluators. MATERIALS AND METHODS: The crown margin evaluation used 16 surfaces of four crowns fitting to three extracted caries-free teeth fitted into a dentiform. The teeth (nos. 14, 20, and 29) were prepared for a full cast (gold) crown using a chamfer finish line configuration, with some margins supragingival and others subgingival. After final impressions and working casts were made, die spacer was applied to the marginal area of the die before waxing to vary the marginal opening. The dentiform was placed in a mannequin in a supine position. Predoctoral students (N = 10) and prosthodontists (N = 9) evaluated each axial surface of each crown in the zone along the margin with an explorer and rated each surface as either "clinically acceptable" or "unacceptable." After casting, the axial marginal openings were measured with Image Pro Software using a digital microscopic image of the surface. Each participant repeated the margin evaluations 6 months later. RESULTS: Upon casting, marginal gaps ranged from 40 microm to 615 microm. The proportions of prosthodontists and of predoctoral students rating a given surface as "clinically unacceptable" were highly correlated (Spearman rank correlation = 0.81, p= 0.0001). The prosthodontists did not provide more or fewer ratings of clinical acceptability than the students, although kappa results indicated that the prosthodontists might be more consistent among themselves than the student raters. Upon re-evaluation, both groups rated between one and six of the surfaces differently than they had previously: the median number of inconsistencies was 1 for prosthodontists and 3 for predoctoral students. The prosthodontists tended to have fewer inconsistencies than the predoctoral students (0.05 < p < 0.10 Wilcoxon rank sum test), but this was not statistically significant. CONCLUSION: The data provided evidence that those surfaces associated with greater margin gaps tended to have a greater proportion of ratings of "clinically unacceptable." The proportion of prosthodontists and predoctoral students rating a margin "clinically unacceptable" were highly correlated. Prosthodontists tended to have fewer inconsistencies than predoctoral students, but that difference was not statistically significant.     

Predictors of academic performance of first year dental undergraduates in Sri Lanka: a re‐evaluation following curriculum changes

The dentistry course in Sri Lanka is conducted in English, a second language for its students. A decade ago, English language proficiency was the key factor in predicting the academic performance of first year dental undergraduates. Since then, changes have been introduced to the teaching programme and examination format to minimise the effect of language proficiency on their performance. This study aimed at re‐evaluating the factors influencing academic performance in a similar academic cohort. A total of 306 first year students in five consecutive academic years ranging in age from 20 to 24 years (77% of the total number registered, 36.3% men) were recruited, and a questionnaire was used to collect data regarding demographics, previous academic ability and perceived levels of difficulty of the first year course, English language and its sub‐skills. Performances of the English language test and cumulative GPA of the first year course were used as objective indicators of language competency and academic performance respectively. The data were analysed using SPSS 11.5. Hierarchical Regression Analysis revealed that English language proficiency, gender and previous academic ability were the significant predictors of GPA. Students who received a lower GPA perceived English as considerably more difficult compared to the academic course itself; however, students who obtained a higher GPA perceived the opposite. Students' language competency remains the major predictor of academic performance, although previous academic ability and gender emerge as significant predictors. The perceived difficulty, however, of the dental course and of studying in English may also be predictors of student academic performance.     

The influence of maxillary gingival exposure on dental attractiveness ratings

This study examined the influence of maxillary gingival display on the attractiveness ratings awarded by lay people. One hundred and twenty university students (94 females, 26 males) were shown seven photographs of a male and seven photographs of a female subject, each with varying levels of gingival display ranging from -2 to +4 mm. Attractiveness ratings were recorded on a 10-point numerical scale for each of the photographs. The photographs where the full height of the incisors were revealed and no gingival tissue was visible (0 mm of gingiva) were rated as the most attractive. Gingival display of more than 2 mm was rated as progressively less attractive. Linear regression analysis revealed that those students who had received orthodontic treatment rated the photographs representing the female student as more attractive than those representing the male (P < 0.05).     

The improvement of technical skills in preclinical courses.

One hundred fifty-four freshmen dental students were administered a fine motor ability test prior to and at the completion of a series of preclinical technique courses. The pre- and posttest performances were compared for each student to determine whether an improvement of technical skill had occurred. The pre- and posttests were also graded using the rank ordered method. The number of students who demonstrated improvement in technical skill was compared to the number of students who improved in grades to establish whether the change in grades was indicative of the observed change in technical skill. Most students improved in technical skill; however, grades did not reflect this improvement.     

Time management behaviors as potential explanatory factors in dental academic achievement

DAT scores and predental GPAs have made the greatest but an imperfect contribution to the reliable estimation of dental students' academic success. One variable unaddressed yet having potential in accounting for unexplained variability in dental school performance is time management behaviors (TMB), a multidimensional attribute that is critical to success in a dental curriculum. Research has indicated a relationship of TMB dimensions (Setting Goals and Priorities, Mechanics of Time Management, Preference for Organization) with undergraduate academic achievement. The purposes of this study were: 1) to ascertain the levels of TMB dimensions reflected in predental students; 2) to validate in predental students the relationship of TMB dimensions and undergraduate academic achievement; and 3) to explore the relationship of TMB dimensions of predental students as explanatory variables of their early academic achievement in the dental curriculum. All individuals who were applicants interviewed for the 1997 entering D.D.S. class and the majority of members of the 1996 entering D.D.S. class participated in this study (n = 192). Each completed the TMB scale. High levels of TMB across dimensions were observed in predental and dental students. Unlike prior research, results showed virtually no relationship of TMB dimensions with undergraduate GPA of these subjects. Though a small relationship was found between dimensions and first-year dental GPAs, no dimension explained a significant amount of variance in any of these dental GPAs beyond that of undergraduate science GPA.     

Evaluation of objective and subjective treatment outcomes in orthodontic cases treated with extraction of a mandibular incisor

Objectives:To analyze changes in occlusal characteristics following mandibular incisor extractions (MIE), to determine the usefulness of wax setups in treatment planning MIE cases and to compare the pre- and posttreatment dental attractiveness between MIE cases and nonextraction (NE) controls.Materials and Methods:The Peer Assessment Rating (PAR) Index was used to score pre- and posttreatment dental casts of MIE cases (n = 14) and matched NE controls (n = 14). Occlusal characteristics were evaluated on diagnostic wax setups and posttreatment casts. Attractiveness of pre- and posttreatment cases judged on intraoral photographs of cases (n = 6) and controls (n = 6) were rated by 76 dental students and 10 laypeople using visual analogue scales (VAS).Results:The difference in PAR score reduction (%) between the MIE and NE groups was not significant. Between the wax setup and posttreatment casts, there were moderate correlations in overjet, overbite, and right canine classification. There was no significant difference in pre- and posttreatment change in VAS scores (%) for attractiveness between the MIE (49.8 ± 4.3 [S.E.]) and control groups (40.8 ± 4.3 [S.E.]). However, there was a significant difference (P = .000) between the observer groups.Conclusions:There were no significant differences in the treatment outcomes of orthodontic cases treated with MIE or NE, indicating that MIE is a valid treatment option. A wax setup is moderately correlated with posttreatment results. Both laypeople and dental students rated posttreatment dental attractiveness higher than pretreatment in MIE and NE groups. Dental students tended to be more critical than laypeople in their ratings.     

Effectiveness of an electronic histology tutorial for first-year dental students and improvement in "normalized" test scores

The effectiveness of an electronic histology tutorial (EHT) as a mode of learning was assessed by comparing performance on two term tests for an EHT class of sixty-nine students and five prior classes (n=347) who learned by traditional methods. The aims of this study were to 1) develop and introduce a self-instructional, computer-aided approach to guide student learning in the first-year histology course at the University of Toronto Faculty of Dentistry; 2) evaluate the effectiveness of the self-study electronic histology tutorial by comparing students' test scores for the EHT group to students' scores in previous years; and 3) evaluate students' acceptance of this novel mode of learning by means of a satisfaction questionnaire. The EHT group performed significantly better on both the general histology and oral histology term tests than the five prior control years (p<0.001), yet there were no significant differences in overall GPA between the groups, suggesting that the improvement was specific to the EHT/histology course grades (p=0.1 to 0.47). A statistically significant improvement in performance per unit overall GPA was noted in the test group, which demonstrated an increase in this test score normalized ratio (TSNR) of 3-18 percent in the general histology term test and 7-21 percent in the oral histology term test over the control groups. In addition to determining the effects of the EHT on grade performance, this study sought to evaluate students' acceptance of this alternative mode of learning in comparison to the standard teaching model by means of a satisfaction questionnaire. Overall, students' responses to the questionnaire were positive with an overall mean level of agreement for all ten responses of 4.5 out of 5 (90 percent).     

Efficacy, side-effects and patients' acceptance of different bleaching techniques (OTC, in-office, at-home)

This clinical study compared the efficacy of three different bleaching techniques with respect to the bleaching times required in order to achieve six grades of whitening in human teeth. Any side effects that were noted and the patients' acceptance of the method were recorded by a visual analog scale ranging from 0 to 10. Moreover, epoxy casts from the study teeth were analyzed by scanning electron microscopy in order to detect any potential changes in the enamel surface due to treatments. Thirty-nine volunteers participated in the study and were allocated randomly to one of three different bleaching treatments: Group A (n=13) used Whitestrips (over-the-counter technique; one cycle=30 minutes), Group B (n=13) used Opalescence PF 10% (at-home bleaching technique; one cycle=8 hours) and Group C (n=13) used Opalescence Xtra Boost (in-office bleaching technique; one cycle=15 minutes) until a defined whitening of six tabs compared to the baseline were reached (assessed by the VITA shade guide). All three methods achieved six grades of whitening. The mean treatment time required to reach the defined level of whitening was 31.85 +/- 6.63 cycles in Group A, 7.15 +/- 1.86 cycles in Group B and 3.15 +/- 0.55 cycles in Group C. All products differed significantly from each other in terms of treatment cycles and required treatment time (p<0.001 by ANOVA and Mann-Whitney-U-test). Using the VA scale, side effects noted within the three groups were minimal. Tooth hypersensitivity ranged from 2.62 (Whitestrips) to 3.38 (Opalescence PF), and gingival irritation ranged between 0.23 (Opalescence Xtra Boost) and 0.85 (Whitestrips). The most accepted method was the at-home bleaching technique. None of the teeth studied showed detectable enamel surface changes in the subsequent SEM analysis using 200x and 2000x magnification.     

A communication skills course for undergraduate dental students

Sixty-seven third-year dental students in Dunedin, New Zealand, participated in a communication skills course, using simulated patients, case-based scenarios, videotaped interviews, and class roleplays. The course introduced active listening techniques, taking a medical history, and emotion-handling skills. This course was adapted from an existing course for medical students run by the Department of Psychological Medicine, Dunedin School of Medicine. The results of the student evaluation questionnaire (n = 59) indicated that students rated the course very highly. Retrospective ratings indicated that the students considered communication skills to be significantly more important as a component of their undergraduate training after completion of the course than prior to it. As might be expected, students whose ratings were higher after the course also reported that the course helped them to develop new communication skills and techniques; increased their interest in the subject and their self-confidence; rated the tutor as more effective and the course materials as more helpful; and considered the course to be significantly more stimulating than those students whose ratings of the importance of communication skills remained the same or decreased.