Swedish dentists' decisions on preparation techniques and restorative materials

This study aimed at mapping the preparation techniques and restorative materials that Swedish dentists are using for primary approximal and occlusal carious lesions. It involved sending a pre-coded questionnaire to a random sample of 923 dentists, with eight items concerning approximal and occlusal restorative preparation techniques and dental materials. Responses were received from 651 (70.5%) dentists. To restore a primary approximal carious lesion in an adolescent with low caries activity and good oral hygiene, the tunnel preparation was chosen by 48% of the dentists, the saucer-shaped preparation by 32%, and the traditional Class II preparation by 20%. The most common preparation technique for restoring an occlusal carious lesion was removal of the carious part only, which was chosen by 74% of the dentists. For a lower second molar with a minor occlusal caries lesion combined with a suspected dentin lesion as judged radiographically, about half of the dentists chose to restore the carious part only and 27% would seal the rest of the fissure system in addition. For a similar lesion with no obvious radiolucency in the dentin, about 1/3 chose the 'no treatment' alternative, 1/3 fluoride treatment, and the rest fissure sealing or other techniques. Composite was used most often and amalgam least often for both approximal and occlusal carious lesions.     

Short-time infusion of oxaliplatin in combination with capecitabine (XELOX30) as second-line therapy in patients with advanced colorectal cancer after failure to irinotecan and 5-fluorouracil.

BACKGROUND: The efficacy of oxaliplatin combined with capecitabine (XELOX) as second-line therapy in patients with advanced colorectal cancer (ACRC) resistant to irinotecan is not well established. Oxaliplatin induces acute, cold-induced neuropathy in most patients. The incidence is claimed to be infusion rate-dependent and therefore a 2-h infusion is recommended. PATIENTS AND METHODS: For practical and economic reasons, but also for patient's convenience, we performed a phase II study to examine XELOX30 (capecitabine 1000 mg/m2 orally twice daily on days 1-14 and oxaliplatin 130 mg/m2 as a 30 min infusion on day 1) in patients with ACRC resistant to irinotecan. In addition the pharmacokinetics of oxaliplatin was studied. RESULTS: From November 2002 to September 2003, 70 patients with ACRC were treated with XELOX30. Median age was 62 (range 33-74 years) years and median performance status was 1 (range 0-2). The median number of courses was four (range 1-12) and median cumulative dose of oxaliplatin was 530 (range 125-1560) mg/m2. The response rate was 17% (95% CI 10-23), median time to progression (TTP) was 5.4 months (95% CI 4.6-6.4) and median survival 9.5 months (95% CI 8.5-11.2). White blood cell count (WBC) and performance status were significantly correlated to TTP. Neurotoxicity was moderate: grade 1 56%, grade 2 17% and grade 3 6%. Other grade 3 toxicities were nausea/vomiting 9%, diarrhoea 14% and PPE 8%. The maximum blood concentration and total body clearance of oxaliplatin was higher than previously reported in studies examining 2-h infusions, but the volume of distribution and terminal half-life was in close agreement with previous results. CONCLUSION: XELOX30 is a very convenient second-line regimen in ACRC with an activity and safety profile similar to other oxaliplatin schedules.     

Irinotecan combined with bolus 5-fluorouracil and folinic acid Nordic schedule as first-line therapy in advanced colorectal cancer.

BACKGROUND: This multicentre phase II study evaluated the efficacy and safety of irinotecan combined with the Nordic schedule of 5-fluorouracil (5-FU) and folinic acid (FA) as first-line therapy in patients with advanced colorectal cancer. PATIENTS AND METHODS: Seventy-four patients with measurable disease and a WHO performance status of 2 or less were treated with irinotecan 210 mg/m(2) as a 30-90 min intravenous infusion on day 1, followed by 5-FU 500 mg/m(2) and FA 60 mg/m(2) bolus on days 1 and 2, every 2 weeks, until disease progression or unacceptable toxicity. The primary end point was the objective response rate. RESULTS: Twenty-nine out of 68 evaluable patients achieved a complete (n = 7) or partial (n = 22) response, leading to an overall response rate of 43% [95% confidence interval (CI) 31% to 55%]. The median duration of response was 10 months. The estimated median time to progression and survival were 6.4 months (95% CI 5.4-9.0) and 15.6 months (95% CI 13.3-19.0), respectively, in the intention-to-treat population. A total of 860 cycles were administered to 74 patients. Neutropenia was the main adverse event with grade 3-4 toxicity in 66% of patients and 17.5% of cycles. Grade 3-4 non-haematological toxicities were infrequent and included diarrhoea in 16% of patients and 2% of cycles and nausea/vomiting in 10% of patients and 1% of cycles. CONCLUSIONS: Irinotecan combined with the bolus Nordic schedule of 5-FU/FA is active in advanced colorectal cancer with an easily managed safety profile which ensures good schedule compliance. The low incidence of grade 3-4 non-haematological toxicity justifies the further evaluation of this combination in the context of randomised clinical trials.     

The effect of a NaF solution and a fluoride varnish on the acid resistance of root dentin

Sectioned root dentin surfaces were treated with either a NaF solution for 10 min or a fluoride varnish for 48 h and then exposed to 1 M acetate buffer pH 5.8 for 20 h. Microradiographs of non-fluoride treated specimens (controls) regularly showed a partially demineralized zone extending from the surface. The NaF-treated specimens exhibited a lesion with alternating radiopaque and radiolucent zones, which had a mean total depth equal to that of the controls. The varnish-treated specimens showed a demineralized zone which was significantly less deep than those observed in the two other groups. Elemental analyses performed by an electron microprobe showed a positive correlation between the amount of F incorporated and the acid resistance of the tissue.     

Quality of life during radiotherapy for rectal cancer

The aim of this study was to assess symptoms and health-related quality of life (HRQL) during (neo)adjuvant radiotherapy for rectal cancer. Patients receiving pelvic radiotherapy 50 Gy for rectal cancer, were studied prospectively (n=42). The European Organization for Research and Treatment of Cancer (EORTC) questionnaires quality of life-core 30 QLQ-C30 and QLQ-CR38 and a 5-day symptom diary were completed at the start and end of radiotherapy and 4-6 weeks later. At the end of radiotherapy, mean scores of diarrhoea, fatigue and appetite loss had significantly increased (P<0.01) compared with pretreatment scores, but this was not observed for scores for nausea or pain. At the end of radiotherapy, diarrhoea, fatigue, appetite loss, physical function, social function and global quality of life (QL) were significantly worse than the population-based norms. 64% of the patients reported an increase in fatigue and 52% an increase in diarrhoea during radiotherapy. HRQL scores had returned to pre-treatment levels 4-6 weeks after radiotherapy. Thus, diarrhoea, fatigue and appetite loss increased transiently during pelvic radiotherapy.     

Radiographic interpretation and treatment decisions among dental therapists and dentists in Western Australia

All dentists and dental therapists employed in the Community Dental Services in Western Australia were invited to participate in a questionnaire study to find out about their use of radiographs and opinions and knowledge about the diagnosis of approximal caries. Replies were received from 45 dentists (95.1%) and 207 dental therapists (84.0%). Most dentists would not restore a lesion before it appeared on radiograph to have reached the dentine, while therapists were more likely to consider a restoration for a lesion just in enamel. Sixty percent of all respondents thought that a cavity was present when the radiographic lesion was confined to enamel. Fifty-seven percent of dentists thought that an average lesion took at least 12 months to progress from outer enamel to dentine, while a majority of dental therapists thought this would take less than 12 months. Radiographs were not frequently taken by the participants. Operators' opinions about cavity formation were the most important predictor of choice of treatment. In general, these participant's responses were similar to those provided by Norwegian and Dutch respondents in similar surveys conducted 5-6 yr ago, but the present participants worked in an optimally fluoridated area and might therefore have been expected to have adopted more cautious criteria for restorative treatment. Differences between dentists and dental therapists were generally not great. The results suggest that calibration of the operators in the service would offer benefits.     

Genetic variation may explain why females are less susceptible to dental erosion

Not all individuals at risk for dental erosion (DE) display erosive lesions. The prevalence of DE is higher among male subjects. The occurrence of DE may depend on more than just acidic challenge, with genetics possibly playing a role. The aim of this study was to investigate the association of enamel‐formation genes with DE. One premolar and a saliva sample were collected from 90 individuals. Prepared teeth were immersed in 0.01 M HCl (pH 2.2), and enamel loss (μm) was measured using white light interferometry. DNA was extracted from saliva, and 15 single‐nucleotide polymorphisms were analysed. Allele and genotype frequencies were related to the enamel loss of the specimens. Single‐marker and haplotype analyses were performed using sex as a covariate. Mean enamel loss was higher for male donors than for female donors (P = 0.047). Significant associations were found between enamel loss and amelogenin, X‐linked (AMELX), tuftelin 1 (TUFT1), and tuftelin‐interacting protein 11 (TFIP11). Analyses showed significant associations between variation in enamel‐formation genes and a lower susceptibility to DE in female subjects. The results indicate that susceptibility to DE is influenced by genetic variation, and may, in part, explain why some individuals are more susceptible than others to DE, including differences between female subjects and male subjects.