Dentists' perceptions of their professional roles regarding referrals within primary dental care in England: a qualitative study.

OBJECTIVE: To describe dentists' perceptions of their professional roles, including the reasons why they make, accept or decline patient referrals within primary dental care in England. BASIC RESEARCH DESIGN: Qualitative semi-structured interviews, conducted via Skype, telephone or face-to-face. Transcripts were analysed using thematic analysis and typologies were developed. PARTICIPANTS: Ten general dental practitioners (GDPs) and 12 community dentists working in England. RESULTS: Five main themes were identified: professional independence, the nature of dental care, the business of dentistry, obscure rules and 'no man's land'. This final theme described a notional gap between GDPs' and community dentists' responsibilities towards vulnerable people, who were perceived by participants to include frail older people, anxious and socially marginalised adults and children with high levels of disease. Three typologies of dentists were generated. 'Entrepreneurs' felt no allegiance to the National Health Service and no obligation to treat vulnerable patients. 'Altruistic carers' were committed to caring for exceptionally deserving patients. 'Pragmatic carers' tried to provide relational dental care (time and emotional support) for vulnerable patients but encountered discouraging systemic barriers. CONCLUSION: Dentists' perceptions of their roles may influence whether and how they provide access to primary dental care for vulnerable people through referral systems. Access issues may exacerbate the oral health inequalities experienced by vulnerable groups. Based upon the findings, approaches are proposed that may encourage and enable the dental workforce to support vulnerable people actively to receive primary dental care.

Root surface strain during canal shaping and its influence on apical microcrack development: a preliminary investigation.

AIM: To determine the root surface strain (RSS) generated during root canal shaping and its effects on apical microcrack development. METHODOLOGY: Twenty-five extracted human mandibular premolars were selected and decoronated. The teeth were instrumented with either the ProTaper (PT) or WaveOne (WO) (Dentsply Maillefer) NiTi rotary systems (n = 10 per group) or used as controls (n = 5). Instrumented root canals were enlarged to ProTaper F4 (size 40, 0.06 taper) or using WaveOne LARGE (size 40, 0.08 taper) instruments according to the manufacturer's instructions. An electrical strain gage (KFG02-120-C1-16, Kyowa Dengyo, Tokyo, Japan) was fixed on the proximal root surface and connected to a strain amplifier via a bridge box in order to measure RSS. During canal shaping, the strain output of the amplifier was recorded. The instantaneous RSS induced by each instrument and the maximum RSSs were determined. All teeth were then stained with contrast media and imaged with micro-computed tomography (micro-CT) at an isotropic resolution of 10 µm to detect microcracks. The mean maximum RSS values (microstrain) and mean number of microcracks recorded for both groups were tested for statistical significance using Mann-Whitney U-test. Presence/absence of microcracks in both groups was compared by chi-square tests. RESULTS: Increased baseline RSS from strain accumulation during canal shaping was observed, with similar maximum RSS (mean ± SD) for PT (416.6 ± 185.1 µstrain) and WO (398.2 ± 163.8 µstrain) (P = 0.94). The interevaluator reliability for microcrack detection using micro-CT had a kappa value of 0.998. Compared to the PT group, there was a trend for fewer samples with microcracks in the WO group (P = 0.051). On the micro-CT images, apical microcracks were detected in 20 PT and 11 WO samples (P = 0.10). The microcracks were observed in the buccolingual direction in all WO and 81% of PT samples. No vertical root fractures were found. The maximum RSS obtained during canal shaping was poorly correlated with the number of microcracks found (R(2)  = 0.093). CONCLUSIONS: Based on these preliminary data, canal shaping appears to cause apical microcracks regardless of the type of rotary instrument motion. Contrast-enhanced micro-CT was able to identify microcracks in roots.

The effect of glutathione on 2-hydroxyethylmethacrylate cytotoxicity and on resin-dentine bond strength.

AIM: To evaluate the influence of reduced glutathione (GSH) application on 2-hydroxyethylmethacrylate (HEMA) cytotoxicity on rat pulpal cells and evaluate the effect of etched-dentine treatment with GSH on the immediate microtensile bond strength (µTBS) of etch-and-rinse adhesive. METHODOLOGY: The cytotoxicity of 10 mmol L(-1) HEMA, 10 mmol L(-1) HEMA + 1 mmol L(-1) GSH, 10 mmol L(-1) HEMA + 5 mmol L(-1) GSH and 10 mmol L(-1) HEMA + 10 mmol L(-1) GSH was compared (6 h and 24 h). Cells viability was measured by means of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, followed by morphological observation of cells. Etched-dentine surfaces were rinsed and treated with one of the following solutions: 2% GSH, 5% GSH or 10% GSH, bonded with Adper Single Bond Plus (3M, ESPE, St. Paul, MN, USA) and restored with resin composite. The control group received no GSH treatment. After 1 day of water-storage at 37 °C, the specimens were subjected to µTBS testing. Cytotoxicity and µTBS data were analysed by one-way anova and Tukey post hoc tests (P < 0.05). RESULTS: There were significant differences between the groups. HEMA elicited a remarkable toxic effect. 10 mmol L(-1) GSH prevented HEMA-induced damage at both exposure times. Whilst 5 mmol L(-1) GSH lost its protective effect at 24-h exposure time and 1 mmol L(-1) GSH showed no protective effect at both exposure times, GSH had no significant effect on the immediate µTBS; however, 5% GSH had higher bond strength value when compared to 10% GSH (P = 0.003). CONCLUSION: Controlled concentrations of GSH had a protective effect against HEMA cytotoxicity. GSH had neither positive nor negative influence on µTBS.

The prevalence of localized juvenile periodontitis in Saudi subjects.

The purpose of this study was to determine the prevalence and sex ratio of localized juvenile periodontitis (LJP) cases in a selected Saudi population, to compare these values with different societies, and to correlate the sex ratio with the presence of Actinobacillus actinomycetemcomitans in the afflicted sites. In a retrospective study over a 3-year period 23 cases of LJP were diagnosed from a group of 5,480 subjects with different forms of periodontal disease. The overall prevalence was 0.42%. The female to male ratio was 1.88:1. The difference in the sex ratio was statistically significant (X = 5.490, P < .05). No statistically significant difference in the sex ratio association regarding the sites afflicted by Actinobacillus actinomycetemcomitans was found.

Central odontogenic fibroma of the maxilla.

The central odontogenic fibroma (COF) is a rare benign odontogenic mesenchymal tumor of jaw bones. The World Health Organization (WHO) recognizes two variants of COF namely: 1) Epithelial-rich type (WHO) and 2) epithelial-poor type (simple type). Rare variants like ossifying COF, COF associated with giant cell lesions, and amyloid have been documented. This article presents a case of an epithelial-rich variant of COF in a 24-year-old female. It presented as a bony swelling of the maxilla and appeared as a mixed lesion in radiographs. Histopathology showed a highly cellular fibrous connective tissue stroma with plump fibroblasts and long strands of odontogenic epithelium exhibiting mild eosinophilic to clear cytoplasm. Numerous cementum-like hematoxyphilic calcifications of various sizes akin to dentin or acellular cementum were observed. We believe that clinical and radiographic features of this case may add valuable knowledge to the already existing literature.