Effect of Heat Treatment on Fracture Toughness ( K IC ) and Microstructure of a Fluorcanasite-Based Glass-Ceramic

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73358/1/j.1532-849X.2007.00233.x.pd

Removal of dental amalgam restorations in patients with health complaints attributed to amalgam: A prospective cohort study

Background The Norwegian Ministry of Health and Care Services initiated a project including experimental treatment for patients with health complaints attributed to amalgam restorations. Objective The aim was to evaluate changes of general health complaints in patients who participated in the project and had all amalgam restorations removed. Methods The project was designed as a prospective cohort study and organised by the Dental Biomaterials Adverse Reaction Unit in Bergen, Norway. The dental treatment was provided by the patient's local dentist. The main target group consisted of patients with medically unexplained physical symptoms, attributed to dental amalgam restorations (Amalgam cohort). The primary comparison group consisted of patients with medically unexplained physical symptoms without attribution to dental amalgam restorations (MUPS cohort). Primary outcome was self-reported general health complaints (GHC index) at follow-up 12-months after completed amalgam removal. Results In the Amalgam cohort, a significant reduction of GHC index from 43.3 (SD 17.8) at baseline to 30.5 (SD 14.4) at follow-up (mean reduction 12.8, SD 15.9; n = 32; P < .001) was observed. The change scores for GHC index indicated that the reduction of complaints was significantly higher (P = .004) in the Amalgam cohort compared with the MUPS cohort (mean reduction 1.2, SD 12.3, n = 28). After adjustment for age, gender, education and baseline GHC index, the mean adjusted difference was −8.0 (95% confidence interval from −15.4 to −0.5; P = .036). Conclusion In a group of patients with medically unexplained physical symptoms, which they attributed to dental amalgam restorations, removal of amalgam restorations was followed by a significant reduction of health complaints.publishedVersio

Acidogenic Potential of “Sugar-Free” Cough Drops

A patient presented with extensive marginal ditching around restorations recently placed during whole-mouth rehabilitation. The patient was not xerostomic and was otherwise normal except for the self-reported excessive use of “sugar-free” cough drops sweetened with sorbitol and Isomalt® (an equimolar mix of glucosyl-mannitol and glucosylsorbitol). This prompted an in vitro investigation to determine whether Streptococcus sobrinus 6715, a cariogenic streptococcus, could grow and produce acid in growth medium containing an aqueous extract of such “sugar-free” cough drops. The results indicate that S. sobrinus 6715 uses Isomalt® and sorbitol extensively, producing terminal culture pH as low as 4.2 when grown on medium with cough drop extract containing these sugars. This pH is sufficient to demineralize dental enamel. Patients should be cautioned against the chronic overuse of “sugar-free” cough drops and other “sugar-free” confections sweetened with a mixture of Isomalt® and sorbitol