Taste disorders following cancer treatment: report of a case series.

PURPOSE: To present the findings of combined oral assessment and gustometry testing of a series of head and neck and hematologic malignancies in patients with self-reported taste change after cytotoxic therapies. METHODS: Patients with acute myeloid leukemia (AML), multiple myeloma (MM), and head and neck cancer (HNC) were evaluated for taste function. Chemical gustometry was conducted assessing chemosensory qualities that included sweet, sour, salty, bitter, umami, and spicy. NCI Common Terminology Criteria for Adverse Events (CTCAE) 4.0 and the Scale of Subjective Total Taste Acuity (STTA) were used to describe taste symptoms. Saliva flow rates were measured to determine the presence of hyposalivation. Patients were provided treatment trials for taste dysfunction, including zinc supplements, or medications that included clonazepam, megestrol acetate, and the cannabinoid dronabinol. RESULTS: According to STTA, hematology cases reported the incidence of grades 2 and 3 taste disturbances as 60% and 40%, respectively. For HNC patients, the incidence of grades 2 and 3 was 44% each. Gustometry tests confirmed dysgeusia in all patients evaluated. In the hematology group, 80% of patients exhibited a decrease in sweet taste perception, and no patients correctly identified umami taste. In the HNC group, most patients could not identify salt taste, 66% of patients reported "no sensation" with spicy taste, bitter taste was reduced in some, and increased or altered in others, while only one patient could identify umami taste. In the hematologic and HNC patient groups, 80% and 66% reported grade 2 dry mouth, respectively, according to CTCAE 4.0. After treatment for taste dysfunction, 71% of all patients in the present study reported improvements in taste function. CONCLUSIONS: Persisting dysgeusia in cancer survivors may be assessed by patient report and taste testing. The taste most affected in our patients was umami. Treatment trials with current interventions for dysgeusia appeared effective and should be considered in cancer survivors. Understanding taste and flavor function during and following cancer treatment is important in developing rational prospective preventive and interventional strategies.

Effects of a combined application of potassium oxalate gel/adhesive agent on dentin permeability in vitro.

PURPOSE: To test the effects of sequential application of potassium oxalate gel/adhesive agent on in vitro dentin permeability. MATERIALS AND METHODS: Full crown preparations were made in extracted human molars to expose deep coronal dentin. The roots and pulp were removed and the resulting crown segments were connected to a special device (Flodec) to permit the measurement of the permeability of the specimens before and after treatments. Minimum and maximum permeability were recorded after smear layer and phosphoric acid treatment. A new smear layer was created and the permeability measured after the crowns were bonded with Single Bond (3M ESPE), One-Up Bond F (Tokuyama), and AdheSE (Ivoclar Vivadent), either according to manufacturer's instructions or after treating the acid-etched dentin with a 3 wt% potassium oxalate gel. The results were expressed as a percentage of maximum permeability values. Impressions and epoxy resin replicas from the crown segments were produced for SEM examination. RESULTS: None of the adhesives were able to eliminate the fluid flow through dentin. Two-way ANOVA revealed that the application of potassium oxalate prior to the bonding procedures was the most effective technique in reducingthe dentin permeability (p < 0.05), regardless of the adhesive used. SEM micrographs showed that transudation of dentinal fluid could be identified on the surfaces of all replicas. CONCLUSION: The use of potassium oxalate gel was effective in reducing the permeability of bonded dentin.

Effect of an additional hydrophilic versus hydrophobic coat on the quality of dentinal sealing provided by two-step etch-and-rinse adhesives.

OBJECTIVE: To test the hypothesis that the quality of the dentinal sealing provided by two-step etch-and-rinse adhesives cannot be altered by the addition of an extra layer of the respective adhesive or the application of a more hydrophobic, non-solvated resin. MATERIAL AND METHODS: full-crown preparations were acid-etched with phosphoric acid for 15 s and bonded with Adper Single Bond (3M ESPE), Excite DSC (Ivoclar/Vivadent) or Prime & Bond NT (Dentsply). The adhesives were used according to the manufacturers' instructions (control groups) or after application to dentin they were a) covered with an extra coat of each respective system or b) coated with a non-solvated bonding agent (Adper Scotchbond Multi-Purpose Adhesive, 3M ESPE). Fluid flow rate was measured before and after dentin surfaces were acid-etched and bonded with adhesives. RESULTS: None of the adhesives or experimental treatments was capable to block completely the fluid transudation across the treated dentin. Application of an extra coat of the adhesive did not reduce the fluid flow rate of adhesive-bonded dentin (p>0.05). Conversely, the application of a more hydrophobic non-solvated resin resulted in significant reductions in the fluid flow rate (p<0.05) for all tested adhesives. CONCLUSIONS: The quality of the dentinal sealing provided by etch-and-rinse adhesives can be significantly improved by the application of a more hydrophobic, non-solvated bonding agent.