A comparative study of student vs supervisor diagnoses of anatomical abnormalities affecting the TMJ

INTRODUCTION: The use of modern teaching methods and learning tools by educators to ensure competent graduates has been encouraged. At the Department of Odontology, University of Pretoria, School of Dentistry, four diagnostic screening tests were tested as learning tools, in order to teach undergraduate dental students to diagnose abnormalities affecting the osseous components and associated muscles of mastication of the temporomandibular joint (TMJ). These screening tests are known as joint play, end feel, static pain and dynamic pain. OBJECTIVES: The aim of this study was to determine if dental students would be able to diagnose abnormalities affecting the osseous components and associated muscles of mastication of the TMJ using these four screening tests, as well as to compare their diagnosis with the diagnosis of a prosthodontist. METHODS: One hundred joints were randomly examined for abnormalities by 50 dental students and a prosthodontist. The diagnoses were recorded on a diagnostic form and entered into an electronic Microsoft Excel ® database. RESULTS: Of the 100 joints examined, 78 of the diagnoses made by the students were in agreement with that of the prosthodontist, which is highly significant (p < 0.001). Conclusion: The tests were used successfully by the majority of the students to make a correct diagnosis.www.sada.co.zaam201

Fracture strength of cusp-replacing fibre-strengthened composite restorations

INTRODUCTION : Fracture of composite restorations, especially when one or more cusps are replaced, is a common reason for failure. Finite element analysis has shown that crack propagation at the tension side of the restoration signals the failure. AIMS AND OBJECTIVES : The strengthening effect of placing a fibre substructure on the tension side was investigated and the results compared with the fracture strengths of a conventional posterior composite without a substructure (control) and of a composite reinforced with fibres incorporated within the composite. DESIGN : The study was an in vitro experimental blind study. METHODS : 75 extracted lower first molars were divided into three groups of 25 teeth each to allow for the comparisons and the restorations were placed. All specimens were thermocycled for 500 cycles between 5°C and 55°C with a dwell time of 30 seconds. Each restoration was subjected to loading on a Universal testing machine at a 30° angle to the long axis of the tooth, until fracture occurred. Maximum force before failure (Fmax in N) was recorded. RESULTS : The results indicated a significantly higher strength for the composite resin restorations placed on a fibre substructure. CONCLUSION : A uni-directional fibre substructure is recommended to achieve greatest strength.http://www.sada.co.zaam201

Comparison of a custom made electronic record book database with a traditional student record book - for recording clinical procedural credits and continuous clinical assessments in Restorative Dentistry

INTRODUCTION : Comparison of a custom designed electronic record book database with a traditional student record book in Dentistry has not been documented. AIM : To develop an electronic record book database (ERBD) to record and calculate continuous clinical assessment (CCA) marks of students in Restorative Dentistry and to compare the efficiency of the ERBD system with the traditional student record book (TSRB). METHODS : Data was obtained from 1276 dental procedures performed by fifty five consenting final year students. Clinical supervisors and students were calibrated to record credits and CCA marks on a designated assessment form. In practice, the recorded data were manually transferred to the TSRB on a daily basis. The ERBD was designed as an electronic Excel® spreadsheet which enabled daily automatic calculating and updating of credits and CCA marks for each student. After a month the times taken to transfer these data from the TSRB and the ERBD to electronic class lists were recorded in minutes and analysed using the Student’s t-test. RESULTS : Significant differences (p < 0.0001) between the times were recorded. Discussion: The administrative procedure was 14 times faster when the ERBD was used. CONCLUSION : The ERBD was significantly more efficient than the TSRB.http://www.sada.co.zaam2016OdontologyProsthodontic

Fracture behaviour patterns of cusp-replacing fibre strengthened composite restorations

OBJECTIVES : To investigate and compare, in vitro, the fracture behaviours of three types of cusp-replacing posterior composite resin restorations. METHODS : Standard preparations for posterior composite restoration of the mesio-lingual cusp were cut on seventy- five extracted lower left first and second molars and restorations placed. Group A (control, n =25) with a conventional posterior composite resin, Group B (n=25): resin reinforced with nano-scale electrospun glass fibres Group C (n=25) :resin reinforced with a fibre substructure. Specimens were thermocycled for 500 cycles between 5°C and 55°C with a dwell time of 30 seconds, then embedded in plastic cylinders in acrylic resin. The specimens were loaded in a universal testing machine at a 30° angle to the long axis of the tooth until fracture occurred. Fracture patterns were highlighted by staining, studied under a microscope and classified as favourable (restorable) or unfavourable (non-restorable). Sub-classification included adhesive and cohesive failures. RESULTS : Group C exhibited significantly more “restorable” fractures. Group B displayed significantly more “nonrestorable” fractures. Fracture patterns differed significantly between the two fibre-strengthening techniques. (Fisher’s Exact Test p = 0.05) CLINICAL SIGNIFICANCE : Resin restorations reinforced with glass-fibre substructures are more readily repaired after fracture, saving tooth structure, and reducing costs to the patient.http://www.sada.co.zaam201

Antimicrobial efficacy of nine different root canal irrigation solutions

Endodontic therapy is a debridement procedure that requires removal of the irritants from the canal and periapical tissues if the treatment is to be successful. It is well established that bacteria are the main etiological factors in the development of dentinal caries and its progression to pulpal and periapical disease. E. faecalis is the bacterial species most frequently recovered from root-filled teeth. Studies have shown that E. faecalis is able to withstand a high alkaline environment such as the one generated by calcium hydroxide. The resistance appears to be related to a cell proton-pump that is necessary for survival of the bacterium at high pH. Therefore, E. faecalis is able to form biofilms even in calcium-hydroxide-medicated root canals. In addition, under starved conditions, this resilient organism shows tolerance to sodium hypochlorite, heat, hydrogen peroxide, acid and ethanol. E. faecalis can also survive extended periods of starvation in water, within water-filled dentinal tubules, and in human serum.http://www.sada.co.zaam201

The influence of glide path preparation on the failure rate of WaveOne reciprocating instruments

INTRODUCTION: The aim of this study was to determine the influence of two different glide path preparation methods on the fracture rate of the Primary 25/08 WaveOne reciprocating instrument. Preparation times for different glide path methods and total time for root canal preparation, with and without prior glide path preparation, were also calculated. MATERIALS AND METHODS: ISO 15, 0.02 taper Endo-Training- Blocks (n = 300) were selected and randomly divided into three main groups (n = 100): Group 1: no glide path (control); Group 2: glide path preparation with stainless-steel hand files; and Group 3: glide path preparation with rotary PathFiles. The time taken to prepare each glide path was recorded. The specimens in each main group were then randomly assigned into five subgroups (n=20). New Primary 25/08 WaveOne files were used for canal preparation in each subgroup. The outcome was measured by recording how many simulated canals could be shaped with one WaveOne reciprocating file in each subgroup before instrument breakage occurred. The average time it took to prepare each of the simulated canals was calculated and recorded. The data were collected and statistically analysed using the ANOVA / Bonferroni test. RESULTS: Glide path preparation with PathFiles was significantly faster than with hand files (P<0.001). After the glide path preparation had been performed with PathFiles, a greater number of simulated canals could be prepared before failure of the WaveOne file (P<0.001). Root canal preparation time was significantly shorter (P<0.001) when an initial glide path had been prepared with PathFiles. CONCLUSION : Initial glide path preparation with PathFiles resulted in shorter preparation times and allowed a higher number of simulated canals to be prepared before failure of the WaveOne instruments.http://www.sada.co.za2015-07-30am201

Errors in root canal preparation : a review of the literature and clinical case reports

Chemo-mechanical preparation and the removal of infected dentine in order to eliminate microorganisms and avoid apical periodontitis remain the main objectives in endodontic treatment. Mechanical preparation of the root canal system not only provides the space for obturation but also facilitates disinfection of the root canal system through the use of irrigation solutions. Iatrogenic preparation errors affect the root canal anatomy and can result in apical canal transportation, uncentered preparations, ledge formation, or perforations. These errors are all associated with inferior outcomes of endodontic treatment. In this paper, the authors will discuss a review of the literature which considers some of these procedural errors and, using clinical case studies, will illustrate the appropriate clinical management when errors do occur.https://www.sada.co.za/the-sadjam2021Odontolog

In vitro evaluation of root canals obturated with four different techniques. Part 2 : Apical leakage

No abstract available.www.sada.co.zaam201

In vitro evaluation of root canals obturated with four different techniques. Part 3 : Obturation of lateral canals

According to Schilder,1,2,3 the main objective of endodontic treatment procedures should be the cleaning and filling of the root canal in its entire extent, including all lateral canals and apical ramifications.http://www.sada.co.zaam2013mn201

In vitro evaluation of root canals obturated with four different techniques. Part 1 : Radiographic evaluation

No abstract available.http://www.sada.co.zaam201