Cyclic fatigue testing of denture teeth for bulk fracture

Objectives

Clinical experience with implant-supported dentures indicates that fracture and chipping of teeth are becoming an issue. Tooth fracture and chipping rates of approximately 2.5% per year are being experienced at one university. There has been no standardized test developed for bulk fracture or chipping of denture teeth. Such a test would aid in the development of improved teeth and in their evaluation.

Methods

Central incisor teeth were embedded in acrylic and loaded on incisal edges at 90° to their long axes. Teeth tested included ones commercially available and two sets made from improved materials designed to increase toughness. Cyclic loading was done at 5 Hz from 20 N to 135 N, 150 N, 175 N and 200 N. Data was analyzed using lifetime analysis software fit at each of the accelerated loads and then extrapolated to clinical use loads (Alta 7, Reliasoft Corp.) Clinical use loads were derived from extrapolation of probability of failure (Pf) data to 2.5% Pf.

Results

When carefully embedded, teeth could be reproducibly loaded to failure by bulk fracture involving a failure mode similar to that seen clinically. Clinical use loads were calculated to be in the range of 70 N. Results from accelerated loading could be fit to similar probability of failure distributions allowing extrapolation to clinical use loads.

Significance

This work was able to develop a clinically valid bulk fracture test for the fatigue failure of incisor denture teeth. It appears that teeth fabricated with improved materials will be expected to perform better clinically. Thus both the null hypotheses were rejected.     

Should money follow the patient: Financial implication for being the National Centre for the Treatment and Management of Pelvic and Acetabular Fractures in Ireland

Background

Pelvic and acetabular fractures are complex injuries requiring specialist treatment. Our institution is the National Centre for Treatment and Management of these injuries.

Aim

To audit all referrals to our institution over a 6-month period and calculate the cost incurred by being the national referral centre.

Methods

Retrospective review of database, and subsequent allocation of Casemix points to assess total cost of treatment for each patient referred to our institution.

Results

103 patients referred with pelvic or acetabular fracture for operative management. The furthest referral distance was 181 miles. Over-all, the length of stay was 15.4 days. The average inclusive cost for a referral to our unit for operative management was €16,302.

Conclusion

Pelvic and acetabular fractures are complex injuries that require specialist referral unit management. However for these units to remain sustainable money needs to “follow the patient”.     

A look at the thoracic surgery workforce in Canada: how demographics and scope of practice may impact future workforce needs

Background

The purpose of this study is to describe the demographics, training and practice characteristics of physicians performing thoracic surgery across Canada to better assess workforce needs.

Methods

We developed a questionnaire using a modified Delphi process to generate questionnaire items. The questionnaire was administered to all Canadian thoracic surgeons via email (n = 102) or mail (n = 35).

Results

In all, 97 surgeons completed the survey (71% response rate). The mean age of respondents was 47.7 (standard deviation 9.1) years; 10.3% were older than 60. Ninety respondents (88.7%) were men, 95 (81.1%) practised in English and 93 (76%) were born in Canada. Most (90.4%) had a medical school affiliation, with an equal proportion practising in community or university teaching hospitals. Only 18% of respondents reported working fewer than 60 hours per week, and 34% were on call more than 1 in 3. Three-quarters of work hours were devoted to clinical care, with the remaining time split among research, administration and teaching. Malignant lung disease accounted for 61.2% of practice time, with the remaining time equally split between benign and malignant thoracic diseases. Preoperative testing (49.4%) and insufficient operating time (49.5%) were the most common factors delaying delivery of care. More than 80% of respondents reported being satisfied with their careers, with 62.1% planning on retiring after age 60.

Conclusion

This survey characterizes Canadian thoracic surgeons by providing specific demographic, satisfaction and scope of practice information. Despite challenges in obtaining adequate resources for providing timely care, job satisfaction remains high, with a balanced workforce supply and demand anticipated for the foreseeable future.     

Patient–Provider Discussions about Colorectal Cancer Screening: Who Initiates Elements of Informed Decision Making?

BACKGROUND

Colorectal cancer (CRC) screening rates remain low among low-income minority populations.

OBJECTIVE

To evaluate informed decision making (IDM) elements about CRC screening among low-income minority patients.

DESIGN

Observational data were collected as part of a patient-level randomized controlled trial to improve CRC screening rates. Medical visits (November 2007 to May 2010) were audio-taped and coded for IDM elements about CRC screening. Near the end of the study one provider refused recording of patients’ visits (33 of 270 patients). Among all patients in the trial, agreement to be audio taped was 43.5 % (103/237). Evaluable patient (n = 100) visits were assessed for CRC screening discussion occurrence, IDM elements, and who initiated discussion of each IDM element.

PARTICIPANTS

Patients were African American (72.2 %), female (63.7 %), with annual household incomes <$20,000 (60.7 %), without health insurance (57.0 %), and limited health literacy (53.7 %).

KEY RESULTS

Although CRC screening was mentioned during 48 (48 %) visits, no further discussion about screening occurred in 23 visits (19 times mentioned by the participant with no response from providers). During any visit, the maximum number of IDM elements was five; however, only two visits included five elements. The most common IDM element discussed in addition to the nature of the decision was the assessment of the patient’s understanding in 16 (33.3 %) of the visits that included a CRC discussion.

CONCLUSIONS

A patient activation intervention initiated CRC screening discussions with health care providers; however, limited IDM occurred about CRC screening during medical visits of minority and low-income patients.KEY WORDS: colorectal cancer, cancer screening, communication, decision making     

A Qualitative Study of Perceived Responsibility and Self-Blame in Type 2 Diabetes: Reflections of Physicians and Patients

BACKGROUND

Despite new treatment therapies and the emphasis on patient activation, nearly 50?% of diabetes patients have hemoglobin A_1c levels above target. Understanding the impact of unmet treatment goals on the physician-patient relationship is important for maintaining quality care in clinical practice.

OBJECTIVE

To explore physicians?? and type 2 diabetes patients?? views of patients?? difficulty achieving diabetes treatment goals.

DESIGN

Qualitative study using in-depth interviews with a semi-structured interview guide.

PARTICIPANTS

Nineteen endocrinologists and primary care physicians and 34 patients diagnosed with type 2 diabetes at least two years prior.

MAIN MEASURES

In-depth interviews with physicians and patients. A multidisciplinary research team performed content and thematic analyses.

KEY RESULTS

Qualitative analysis revealed two main findings, organized by physician and patient perspectives. Physician Perspective: Physicians?? Perceived Responsibility for Patients?? Difficulty Achieving Treatment Goals: Physicians assumed responsibility for their patients not achieving goals and expressed concern that they may not be doing enough to help their patients achieve treatment goals. Physicians?? Perceptions of Patients?? Reactions: Most speculated that their patients may feel guilt, frustration, or disappointment when not reaching goals. Physicians also felt that many patients did not fully understand the consequences of diabetes. Patient Perspective: Patients?? Self-Blame for Difficulty Achieving Treatment Goals: Patients attributed unmet treatment goals to their inability to carry out self-care recommendations. Most patients blamed themselves for their lack of progress and directed their frustration and disappointment inwardly through self-deprecating comments. Patients?? Perceptions of Physicians?? Reactions: Several patients did not know how their physician felt, while others speculated that their physicians might feel disappointed or frustrated.

CONCLUSIONS

Physicians?? perceived responsibility and patients?? self-blame for difficulty achieving treatment goals may serve as barriers to an effective relationship. Physicians and patients may benefit from a greater understanding of each other??s frustrations and challenges in diabetes management.