ABSTRACT
Generally, two techniques are used to fabricate a cast post and core (CPC): direct and indirect. To date, research has made no clear indication as to a comparative level of accuracy between the techniques. Therefore, the purpose of the current study was to compare the accuracy of two techniques to produce CPCs for posterior teeth using a new method. Nine endodontically treated human premolars were used for fabricating CPCs using the direct and indirect methods. A total of 18 CPCs were produced, two for each tooth, cast in high noble type IV gold. A silicone impression material was inserted into the root canals, followed by the CPCs. The remaining material in the space between the canal wall and the CPC was weighed using an electronic precision balance. By evaluating the weight of the silicon specimens, the accuracy and intimacy of fit were obtained. Since the number of samples was small, a Student t-test was used for statistical evaluation at a 90% confidence interval. The CPCs obtained by using each method were independently examined by two clinicians for proper fit. Power analysis indicated that for a 90% confidence interval and 0.8 power value, nine specimens would be necessary to achieve a statistically meaningful test. The mean value for the weight of the nine specimens obtained using the direct method was 10.3 ± 2.6 mg, while the mean value for the corresponding specimens obtained using the indirect method was significantly smaller, 7.4 ± 2.3 mg. The Student t-test value was P = 0.006. The indirect method provided CPCs with a better fit and higher accuracy. The Student t-test demonstrated a significant difference between the direct and indirect procedures. The indirect method is a valuable technique for the dental practitioner when multiple posterior cast posts and cores are necessary or interocclusal space is limited.
Subject(s)
Dental Casting Technique/standards , Dental Prosthesis Design/standards , Post and Core Technique/standards , Bicuspid/pathology , Dental Casting Investment/chemistry , Dental Impression Materials/chemistry , Dental Impression Technique , Dental Marginal Adaptation/standards , Dental Pulp Cavity/pathology , Gold Alloys/chemistry , Humans , Materials Testing , Methylmethacrylates/chemistry , Polyvinyls/chemistry , Siloxanes/chemistry , Surface Properties , Tooth, Nonvital/pathologyABSTRACT
The number of U.S. and Canadian dental schools offering programs for dentists with degrees from other countries leading to the D.D.S. or D.M.D. degree has increased recently. This fact, along with the diversity of educational systems represented by candidates for these programs, increases the importance of identifying valid admissions predictors of success in international dental student programs. Data from 148 students accepted into the international dental studies program at the University of the Pacific from 1994 through 2004 were analyzed. Dependent variables were comprehensive cumulative GPA at the end of both the first and second years of the two-year program. The Test of English as a Foreign Language (TOEFL) and both Parts I and II of the National Board Dental Examination (NBDE) were significant positive predictors of success. Performance on laboratory tests of clinical skill in operative dentistry and in fixed prosthodontics and ratings from interviewers were not predictive of overall success in the program. Although this study confirms the predictive value of written tests such as the TOEFL and NBDE, it also contributes to the literature documenting inconsistent results regarding other types of predictors. It may be the case that characteristics of individual programs or features of the applicant pools for each may require use of admissions predictors that are unique to schools.
Subject(s)
Education, Dental , Educational Measurement , Foreign Professional Personnel/education , California , Certification , Clinical Competence , Dentistry, Operative/education , Educational Measurement/methods , Forecasting , Humans , International Educational Exchange , Interviews as Topic , Language , Motor Skills , Prosthodontics/education , School Admission Criteria , Schools, Dental , United StatesABSTRACT
A method is presented for measuring interalveolar dimension (IAD) of existing dentures using a caliper. Directions for construction of an IAD gauge are included. This device is easy to construct and "zeroes out" in the closed position. The measurement is useful for determining occlusal vertical dimension (OVD) in new dentures and for monitoring changes over time. Its dimension is entered in the patient record for future reference.
Subject(s)
Denture, Complete , Jaw Relation Record/instrumentation , Vertical Dimension , Calibration , Dental Occlusion, Centric , Equipment Design , Humans , Mouth, Edentulous/rehabilitation , Surface PropertiesABSTRACT
The authors have compiled a set of solutions to the most common issues influencing the success of complete denture cases. A brief review and discussion of occlusal vertical dimension is presented, followed by a troubleshooting guide to problems such as inadequate retention and stability, discomfort, and other problems affecting treatment outcome.
Subject(s)
Denture, Complete , Adaptation, Psychological , Deglutition Disorders , Denture Retention , Denture, Complete/adverse effects , Denture, Complete/psychology , Humans , Mastication , Patient Satisfaction , Speech Disorders/etiology , Stomatitis, Denture/etiology , Vertical DimensionABSTRACT
This article discusses a simple technique for fabricating a new set of complete dentures when there is a reasonable existing upper and lower denture pair. This method reduces the number of appointments needed, and may be very helpful in treating patients with transportation difficulties, especially when the dentist is able to perform some simple laboratory procedures such as mounting the case on the articulator. The technique is well-suited for a "worn-out" set of complete dentures.
