The level of evidence in prosthodontics in relation to author's characteristics: An analysis of three leading prosthodontics journals.

Purpose: The purpose of this study was to examine the level of evidence (LOE) characteristics and associated factors that change over time in three leading prosthodontics journals. Materials and methods: Articles published in The Journal of Prosthetic Dentistry (JPD), International Journal of Prosthodontics (IJP), and Journal of Prosthodontics (JP) in 2013 and 2020 were reviewed by eight independent reviewers. After applying exclusion and inclusion criteria, the number of authors, the corresponding author's educational degree, corresponding author's origin in each clinical research article were recorded. The included articles were rated by reviewers according to the level of evidence criteria and proposed level of evidence-associated factors. Descriptive statistics, univariable, and binary logistic regression analysis were performed to investigate dependent variables and potentially associated factors. All independent variables with a significant effect were analyzed by using a multivariable test. The entry and exit alpha level were set at αE = 0.15. The statistical significance was set at α = 0.05. Results: A total of 439 articles from 3 selected journals for the years studied met the inclusion criteria. The percentages of level 1, 2, 3, 4, and 5 articles were 2.7 %, 11.4 %, 9.6 %, 13.4 % and 62.9 %, respectively. Univariable analysis results demonstrated significant associations related to the number of authors (P = 0.005), the corresponding author's educational degree (P = 0.022), and the corresponding author's geographic origin (P = 0.042). Multivariable analysis results demonstrated significant associations related to the number of authors (P = 0.002), and the corresponding author's geographic origin (P = 0.014). Conclusions: The number of authors, CA degree, and CA origin had a significant association with the LOE of included prosthodontic studies. Although there was an increase in the number of publications from 2013 to 2020, the level of evidence trend shows no improvement over the years.

A survey on utilization and barriers of digital removable prostheses in the US dental education.

PURPOSE: Gaining knowledge on the extent of digital technology implementation in dental education and the barriers to it will help inform future directions to promote the use of such technology and will enhance dental education. This study aimed to investigate the utilization of digitally fabricated removable prostheses and the potential obstacles to implementing such technology in US dental schools. METHODS: A survey was developed and distributed to the restorative dentistry department chairs and postdoctoral prosthodontic program directors. The survey delivery protocol included follow-up emails 1 week, 3 weeks, and 4 weeks after the initial email. The collected data were analyzed descriptively. RESULTS: The response rate was 85% and 45% for predoctoral and postdoctoral prosthodontic programs, respectively. The results showed that 88.06% of the predoctoral programs and 95.65% of the postdoctoral prosthodontic programs implement digital complete dentures in the curriculum; however, the digital removable partial dentures implementation rate was recorded at 70.77% in predoctoral programs and 61.9% in postdoctoral prosthodontic programs. CONCLUSIONS: Dental schools are challenged by cost, design software limitations, IT and laboratory support, and faculty training. Multifaceted support is instrumental in further implementing digital removable prosthodontics into dental education.

Level of evidence and characteristics of clinical studies published in leading prosthodontics journals.

STATEMENT OF PROBLEM: Data on the level of evidence and the characteristics of studies published in peer-reviewed prosthodontic journals are lacking. PURPOSE: The purpose of this study was to investigate the characteristics and level of evidence (LOE) scores of studies published in 3 leading peer-reviewed prosthodontic journals. MATERIAL AND METHODS: Clinical studies published in the Journal of Prosthetic Dentistry (JPD), the Journal of Prosthodontics (JP), and the International Journal of Prosthodontics (IJP) in 2013 and 2020 were included in the analysis. Abstracts, letters to the editor, book reviews, and animal and laboratory studies were excluded from the investigation. For each study, design, type and LOE scores (Levels 1 to 5), publication year, impact factor (IF) of the journals, geographic origins of the first and corresponding authors, and funding status were recorded. Level 1 and Level 2 were defined as high evidence (HE), and Level 3, Level 4, and Level 5 were defined as low evidence (LE). Descriptive statistics and logistic regression analysis were performed (α=.05). RESULTS: Among the 439 studies included in the analysis, the proportion of HE and LE studies was 14.1% and 85.9%, respectively. According to univariate and multivariate analysis results, year of publication (P=.010 and P=.029), geographic origin of the corresponding author (P<.001), and funding status (P<.001 and P=.002) were significantly associated with the LOE of a study. However, the journal IF was not associated with LOE (P=.328). CONCLUSIONS: Although the number of HE studies in 3 leading prosthodontic journals has increased over time, the total number was still limited compared with LE studies. A further improvement in the overall LOE of clinical studies in prosthodontics is needed.

Custom Made Device for Removal of Removable Partial Denture in a Patient with Manual Impairment.

Manual impairment could be part of the clinical presentation of a number of systemic conditions or traumas. Inability to successfully remove a removable partial denture is one of the contraindications of this type of treatment. This report presents a technique for fabrication of a custom device made chairside to assist a manually impaired patient due to osteoarthritis with the removal of a removable mandibular prosthesis. This technique could allow patients with similar conditions to replace their missing teeth with removable partial dentures, in cases where a fixed restoration is not an option.

Digital Workflow for Double Complete Arch Zirconia Prostheses Utilizing a Novel Scan Body.

The purpose of this clinical report is to present a complete digital workflow for the fabrication of complete arch fixed zirconia implant restorations. An intraoral scanner was used to capture the implants' position at the abutment level and also the patient's existing interim prostheses with the double digital scanning technique. A novel scan body and impression pin were utilized throughout the scanning process which allowed for the accurate and reproducible superimposition of the generated Standard Tesselation Language (STL) files. Prosthesis prototypes were digitally designed and fabricated, tried in, and verified intraorally. The definitive zirconia prostheses were then fabricated and delivered to the patient. This technique can be utilized in both arches overcoming the absence of stable intraoral landmarks for superimposition of STL files.

Retrospective Evaluation of the Status of Advanced Dental Education in Prosthodontics from 2006 to 2016.

The aim of this study was to analyze information about advanced education programs in prosthodontics (AEPPs) collected in American Dental Association (ADA) surveys on advanced dental education from 2006-07 to 2016-17. Data recorded included number of AEPPs and information on program directors, applicants, and enrollees in AEPPs. The results showed that, from 2006 to 2016, there was an increase in the number of AEPPs and enrollment of prosthodontic residents, and the number of applicants per program more than doubled. Despite these increases, steps are needed to increase the number of underrepresented minority residents in prosthodontics. Also, a periodic survey of prosthodontic residents to identify their goals, experiences during training, and career plans could benefit the specialty by providing more insight into the future prosthodontic workforce.

Differences in Lip Support with and without Labial Flanges in a Maxillary Edentulous Population. Part 4: Patient-Centered Analysis.

PURPOSE: To study the subjective differences in facial esthetics evaluations and the ability to distinguish facial changes due to changes in lip support, when evaluated by patients themselves. An additional objective was to study the differences between patients' self-evaluation versus evaluation of other patients. MATERIALS AND METHODS: A total of 22 maxillary edentulous patients from the original sample of 31 patients described in Part 1 of the study, returned to participate in this part of the study. The 22 patients acted as judges for all images in this study, and were therefore un-blinded to the objectives and details of the study. Patients first completed evaluation of facial esthetics on a visual analog scale (VAS). Four digital images per patient (total of 88 images) were evaluated in a random order, twice by all 22 patients. The mean scores from all judgments were used as the outcomes to be analyzed. All patients then took a discriminatory sensory analysis test (triangle test) where they were required to correctly identify the image with a flangeless denture out of a set of 3 images. Both the VAS and triangle test ratings were conducted twice in a random order, and mean ratings were used for all analyses. RESULTS: For VAS analysis, there were no statistically significant or clinically significant differences in facial esthetics ratings between flange and flangeless dentures (p < 0.05). This was true for both profile and frontal images, irrespective of self-evaluation versus evaluation of other patients, years of patient edentulism, and judge (patient) gender. For the triangle test, frontal images had a correct identification rate of 50.2% and profile images of 50.4%, and the difference was not significant. There were no significant differences in triangle test results with respect to self-evaluation versus evaluation of other patients and judge (patient) gender. For all patients, the likelihood of correctly identifying images with flangeless dentures was significantly greater than 1/3, which was the minimum chance for correct identification (p < 0.0001). CONCLUSIONS: Flangeless dentures resulted in no differences in facial esthetics ratings for frontal and profile images, when evaluated by patients. When patients were forced to look for differences, flangeless dentures were detected in half of the image sets. These findings were similar for self-evaluation versus evaluation of other patients and for both patient genders.

Simplifying prosthetic procedures while converting an interim maxillary removable complete denture to an interim implant-supported fixed complete denture.

This article describes a method of converting an interim maxillary removable complete denture to an interim implant-supported fixed complete denture. The advantages of this method are that it provides the opportunity to evaluate the patient's function and esthetics, and helps the accurate transfer of the maxillomandibular relationship to the laboratory. Consequently, the fabrication of the definitive prostheses is accurate, and the final result is predictable.

Delayed setting and hygroscopic linear expansion of three gypsum products used for cast articulation.

STATEMENT OF PROBLEM: Wetting of the set gypsum product used for cast articulation may result in additional expansion. PURPOSE: The purpose of this study was to evaluate the linear expansion of 2 type II and 1 type III gypsum products with and without addition of water after setting, over a time period of 120 hours. MATERIAL AND METHODS: The gypsum products tested in this study were Model Plaster, Lab Plaster, and Mounting Stone. All materials were hand mixed for 5 seconds and mechanically mixed under vacuum for another 15 seconds. The mixes were poured into a linear expansion-measuring instrument (n=20). Half of the specimens were wet with 25 ml of water immediately after the setting time recommended by the manufacturer, and at all time intervals, immediately after data collection. No treatment was performed on the remainder of the specimens. The expansion values were recorded with an expansion-measuring device over a period of 120 hours. Collected data were subjected to a 2-way repeated-measures analysis of variance (ANOVA) (alpha=.05). RESULTS: The highest expansion values for all gypsum products were recorded at 96 and 120 hours. No significant difference in setting expansion values was recorded between these 2 time intervals for any of the materials and treatment conditions (dry vs. wet). Mean expansion values ranged between 0.08% +/-0.06% for dry Mounting Stone specimens at 15 minutes, to 0.57% +/- 0.02% for wet Lab Plaster specimens at 96 and 120 hours. Significant differences (P<.001) between different mounting gypsum products and time were identified. A significant difference between wet and dry specimens was not observed. CONCLUSIONS: The expansion of all gypsum products used for articulation purposes was complete at 96 hours. The type III gypsum product demonstrated lower mean expansion values than type II products. Time and material were more important factors than the dry/wet condition when measuring total expansion values. Type II gypsum products demonstrated 80% or more of the total expansion values in the first 45 minutes, while type III stone demonstrated the same expansion after 24 hours.

Fracture resistance of metal ceramic restorations with two different margin designs after exposure to masticatory simulation.

STATEMENT OF PROBLEM: Although the esthetic outcome of a collarless metal ceramic restoration is superior to that of a restoration with a metal margin, its mechanical strength has not been evaluated. PURPOSE: The purpose of this study was to evaluate and compare the fracture resistance of metal ceramic restorations with metal margins to that of metal ceramic restorations with circumferential porcelain margins, after exposure to masticatory simulation. MATERIAL AND METHODS: Twenty-four metal ceramic restorations were fabricated and paired with 24 cobalt-chrome tooth analogs. Twelve of the specimens had metal margins, while the remainder had circumferential porcelain margins. The restorations were cemented on the metal tooth analogs with a resin-modified glass ionomer luting agent (FujiCEM). All specimens were subjected to cyclic loading by a texture analyzer. A total of 600,000 loading cycles in an aqueous environment was performed, with a minimum load of 0 N and a maximum load of 200 N. Controlled loads were then applied to the teeth until fracture, using a stainless steel rod with a 2-mm-wide, rounded end, mounted in a universal testing machine. The specimens were examined under a stereomicroscope to determine failure mode. Descriptive statistics and the independent t test (alpha=.05) were used to determine the effect of failure loads among the tested groups. RESULTS: The independent t test revealed statistically significant differences among the 2 tested groups (P<.001). The 2 groups presented different failure modes. Metal ceramic restorations with metal margins presented cohesive failures starting from the point of load application. Metal ceramic restorations with circumferential porcelain margins demonstrated a combination of adhesive and cohesive failures, starting from the point of load application and extending to the highest point of the proximal margins. CONCLUSIONS: Metal ceramic restorations with metal margins required significantly greater loads (P<.001) to fracture than metal ceramic restorations with circumferential porcelain margins. (J Prosthet Dent 2009;102:172-178).