Assessing sealant retention using a Poisson frailty model

OBJECTIVE: This paper utilises a Poisson frailty regression model with clustering to report on the failure rates of sealants placed and repaired during a three-year follow-up school-based comprehensive preventive programme. BASIC RESEARCH DESIGN: The programme included annual application/reapplication of light-cured fissure sealants in 210 12-year-old subjects over three years. Sealants placed at the commencement of each year of the programme were assessed for retention 12 months later and repair/reapplication was undertaken at that time for those surfaces judged to require it. An application of a Poisson regression model with random effects ("frailties") and clustering was used in this paper to allow for heterogeneity between subjects. Whilst it appears that the direct utilization of frailty models in determining fissure sealant failure rates has not been reported, it is clearly an appropriate use of this statistical method. A total of 1,544 sealants were placed during the study period. Of these, 1,038 (67.2%) were first placements at baseline and 506 (32.8%) were repairs/reapplications. Of these repairs/reapplications, 206 (40.7%) were performed at first year follow-up and 300 (59.3%) at second year follow-up. RESULTS: The Failure Rate Ratios were statistically significantly greater for second molars cf. first molars (FRR=1.33, p=0.008) and for lower molars cf upper molars (FRR=1.32, p<0.001). Failure rate ratios for sealants placed in the distal occlusal pit and fissures cf. mesial occlusal pit and fissures were significantly higher (FRR=1.33, p<0.001). A significant interaction was found for molar type versus pit and fissure site (p=0.009). There was no significant interaction between molar type and arch. CONCLUSIONS: Sealants placed on second molars, those placed on lower molars and those placed on the distal fissure sites have a higher failure rate. As individual tooth sites in the mouth are not independent, any statistical analysis should allow for these associations when assessing sealant retention.     

Discrimination or discretion? Exploring dentists' views on treating patients with hepatitis C

BACKGROUND: People with hepatitis C (over 259 000 Australians) experience stigma and discrimination, whether perceived or actual, in health care settings. They are less likely to access health care, presenting a major barrier to preventive care and treatment. This study aims to identify factors contributing to such discrimination, barriers to optimal care and strategies to overcome these. METHODS: A purposive sample of 25 Victorian dentists took part in semi-structured interviews to investigate their experiences and attitudes in providing care to people with hepatitis C. Interviews were taped, transcribed and coded for thematic analysis. RESULTS: All dentists interviewed were aware of Standard Precautions. However, there were some who changed practices when seeing a client with hepatitis C, suggesting that they lack confidence in Standard Precautions. When prompted, these dentists were concerned that patients may perceive these actions as discriminatory. All participants, including a small minority who expressed negative views about injecting drug users, felt a professional obligation to treat all patients. CONCLUSIONS: Most dentists have appropriate attitudes regarding patients with blood-borne viruses. However, it is important for dentists to understand how their actions may be interpreted by those who feel sensitive about their status. Dentists need to feel genuinely confident about Standard Precautions and have a realistic view of the infection risk posed by patients with blood-borne viruses.     

The role of the dental hygienist in the public health sector; an Australian perspective

A review of the literature on dental hygienists and their utilisation in the dental workforce is presented. Dental hygienists are employed as part of a dental team in the prevention and management of the two most common and costly oral diseases; dental caries and periodontal disease. The potential scope for dental hygienists in the public health sector in Australia is examined in the light of broader issues relating to changing disease patterns, service delivery and the treatment of patients with special needs. Prevention and treatment of oral disease by the dental hygienist in schools, institutions, nursing homes, hospitals and residential facilities is discussed, with emphasis on such issues as legislation, productivity and quality assurance. Implications for the future training of dental hygienists are presented and recommendations made for increasing their utilisation in the public sector.     

Implant retained overdentures for two patients with severe lichen planus: a clinical report

Lichen planus is a common inflammatory mucocutaneous disease that often manifests itself intraorally. Oral lichen planus can appear in many forms; the most significant form for the edentulous patient is the erosive variety. For the patient, wearing a complete denture is quite dramatic because of the friability of the tissue. Implant-supported overdentures are a predictable treatment for edentulous patients, but this has been discouraged for the patient with erosive lichen planus. This article describes 2 patients with oral erosive lichen planus who were successfully treated with implant-retained mandibular overdentures.     

Complete or ultraconservative removal of decayed tissue in unfilled teeth

Background : The treatment of deep dental decay has traditionally involved removal of all the soft demineralized dentine before a filling is placed. However, this has been challenged in three groups of studies which involve sealing soft caries into the tooth. The three main groups either remove no caries and seal the decay into the tooth, remove minimal (ultraconservative) caries at the entrance to a cavity and seal the remaining caries in, or remove caries in stages over two visits some months apart to allow the pulp time to lay down reparative dentine (the stepwise excavation technique). Objectives : To test the null hypothesis of no difference in the incidence of damage or disease of the nerve of the tooth (pulp), progression of decay and longevity of restorations irrespective of whether the removal of decay had been minimal (ultraconservative) or complete. Search strategy : The Cochrane Oral Health Group Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PubMed and EMBASE databases were searched. The reference lists in relevant papers were checked. Selection criteria : Randomized controlled trials and controlled clinical trials comparing minimal (ultraconservative) caries removal with complete caries removal in unrestored permanent and deciduous teeth. Data collection and analysis : Outcome measures recorded were exposure of the nerve of the tooth (pulp) during caries removal, patient experience of symptoms of pulpal inflammation or necrosis, progression of caries under the filling, time until the filling was lost or replaced. Due to the heterogeneity of the included studies the overall estimate of effect was calculated using a random‐effects model. Main results : Four studies met the inclusion criteria; two stepwise excavation studies and two ultraconservative caries removal studies. Partial caries removal in symptomless, primary or permanent teeth reduces the risk of pulp exposure. We found no detriment to the patient in terms of pulpal symptoms in this procedure and no reported premature loss or deterioration of the restoration. Authors' conclusions : The results of this systematic review reject the null hypothesis of no difference in the incidence of damage or disease of the nerve of the tooth (pulp) irrespective of whether the removal of decay had been minimal (ultraconservative) or complete and accepts the null hypothesis of no difference in the progression of decay and longevity of restorations. However, the number of included studies is small and differ considerably. Partial caries removal is therefore preferable to complete caries removal in the deep lesion, in order to reduce the risk of carious exposure. However, there is insufficient evidence to know whether it is necessary to re‐enter and excavate further but studies that have not re‐entered do not report adverse consequences. Plain language summary : A systematic review of the literature revealed four studies comparing complete and minimal (ultraconservative) caries removal. It was found that partial caries removal in symptomless, primary or permanent teeth reduces the risk of pulp exposure. We found no detriment to the patient in terms of pulpal symptoms in this procedure. Therefore, partial caries removal is preferable to complete caries removal in the deep lesion, in order to reduce the risk of carious exposure. However, there is insufficient evidence to know whether it is necessary to re‐enter and excavate further but studies that have not re‐entered do not report adverse consequences.     

The changing role of dental auxiliaries: A literature review

A review of the literature on dental auxiliaries and their utilization in the dental workforce is presented, and their future role is examined in the light of broader issues relating to changing disease patterns and service delivery. Legislative factors, productivity, quality assurance and the potential scope for dental auxiliaries in both the public sector and private practice setting are discussed. A strategy for adopting a team approach in the delivery of dental services is suggested, which would necessitate the dentist taking on the role of team leader and maintaining responsibility for overall treatment planning and quality assurance. Dental auxiliaries could provide basic preventive and restorative dental services, allowing dentists to concentrate on providing more complex high-technology treatment. Implications for the future training of dental auxiliaries are presented.     

Evaluation of a Fixed,Weight-Based Dose of 3-Factor Prothrombin Complex Concentrate Without Adjunctive Plasma Following Warfarin-Associated Intracranial Hemorrhage

Introduction

Data regarding use of prothrombin complex concentrate (PCC) for international normalization ratio (INR) reversal in warfarin-associated intracranial hemorrhage (wICH) is variable with regards to dosages, adjunctive agents, and product choice. In 2012, we implemented a fixed, weight-based [30 IU/kg] dosing protocol of 3-factor PCC (3PCC) utilizing a rapid infusion rate and no requirement for fresh frozen plasma (FFP) following factor product administration. We aimed to evaluate the impact of this protocol on immediate and delayed INR reversal in patients admitted with wICH in the absence of FFP co-administration.

Methods

We conducted a retrospective review of patients receiving 3PCC following wICH between January 1, 2012 and December 10, 2013. The primary objective was to determine the percentage of patients achieving goal INR (≤1.4) following 3PCC administration. Patients were excluded if their bleed was not intracranial in origin, received a dose outside of the specified protocol, or were given FFP as an adjunctive agent.

Results

We included 35 patients with a mean presenting INR of 3.2 ± 1.3. Thirty patients (85.7 %) achieved goal INR (≤1.4) following one dose of 3PCC. The mean INR after infusion of 3PCC was 1.3 ± 0.2. The median duration between 3PCC infusion and subsequent INR was 48.0 min (30–70.1 min). Vitamin K was utilized in 33 (94.3 %) patients. No patient experienced a thromboembolic event within 7 days of 3PCC administration.

Conclusions

Fixed, weight-based dosing of 3PCC without adjunctive FFP resulted in high rates of complete INR reversal without significant adverse events.     

Plasma protein binding and placental transfer of bupivacaine.

The maternal venous and umbilical venous plasma concentrations of bupivacaine were determined at delivery following epidural administration of the drug to 31 women in labor. In each case the umbilical venous plasma concentration of bupivacaine was lower than the maternal venous plasma concentration. There was no significant difference between the concentration of unbound bupivacaine in umbilical venous and maternal venous plasma at delivery. The difference in umbilical and maternal plasma concentrations of bupivacaine appears to be a consequence of greater bupivacaine binding to maternal than to fetal total plasma protein. The intersubject variation of the ratio of bupivacaine concentration in fetal plasma/bupivacaine concentration in maternal plasma was found to be related to individual variation in the extent of protein binding of bupivacaine in maternal and umbilical plasma and correlated positively with the variation of the ratio of total protein concentration in umbilical and maternal plasma.     

Comparing algorithms for deriving psychosis diagnoses from longitudinal administrative clinical records

Purpose

Registers derived from administrative datasets are valuable tools in psychosis research, but diagnostic accuracy can be problematic. We sought to compare the relative performance of four methods for assigning a single diagnosis from longitudinal administrative clinical records when compared with reference diagnoses.

Methods

Diagnoses recorded in inpatient and community mental health records were compared to research diagnoses of psychotic disorders obtained from semi-structured clinical interviews for 289 persons. Diagnoses were derived from administrative datasets using four algorithms; ‘At least one’ diagnosis, ‘Last’ or most recent diagnosis, ‘Modal’ or most frequently occurring diagnosis, and ‘Hierarchy’ in which a diagnostic hierarchy was applied. Agreements between algorithm-based and reference diagnoses for overall presence/absence of psychosis and for specific diagnoses of schizophrenia, schizoaffective disorder, and affective psychosis were examined using estimated prevalence rates, overall agreement, ROC analysis, and kappa statistics.

Results

For the presence/absence of psychosis, the most sensitive and least specific algorithm (‘At least one’ diagnosis) performed best. For schizophrenia, ‘Modal’ and ‘Last’ diagnoses had greatest agreement with reference diagnosis. For affective psychosis, ‘Hierarchy’ diagnosis performed best. Agreement between clinical and reference diagnoses was no better than chance for diagnoses of schizoaffective disorder. Overall agreement between administrative and reference diagnoses was modest, but may have been limited by the use of participants who had been screened for likely psychosis prior to assessment.

Conclusion

The choice of algorithm for extracting a psychosis diagnosis from administrative datasets may have a substantial impact on the accuracy of the diagnoses derived. An ‘Any diagnosis’ algorithm provides a sensitive measure for the presence of any psychosis, while ‘Last diagnosis’ is more accurate for specific diagnosis of schizophrenia and a hierarchical diagnosis is more accurate for affective psychosis.