Manipulation effects on fluoride release from chemically-cured and resin-modified glass ionomers.
OBJECTIVE
To examine the effect of mixing techniques (hand-mixing vs. trituration) on fluoride release from chemically-cured (Fuji II) and resin-modified (Fuji II LC) glass ionomer products.


METHODS
Fluoride measurements were determined and comparisons made between hand-mixed-type materials that were both hand-mixed (60 seconds) and triturated (10 seconds). Hand-mixed specimens were made using the manufacturer's recommended powder/liquid ratio. Triturated specimens of the same material were made using the same powder/liquid ratio. Disk specimens (8.5 mm diameter, 2 mm thickness; n = 6) were stored in deionized water for 23 hours to obtain Day 1 solutions. Solutions were also obtained at 2, 3, 4, 5, 6, 7, 14, 21, and 28 days after fabrication and were changed 24 hours before fluoride concentration was determined using a fluoride ion selective electrode. Daily rates of fluoride release and 28-day cumulative fluoride totals were calculated. Cumulative data were analyzed by two-way ANOVA and Scheffé's test (alpha = 0.05). Daily results were analyzed by the Mann-Whitney U-test.


RESULTS
A significant difference was observed between materials (P < 0.001). Depending on the kind of material used, the method of manipulation affected the fluoride release. Data analysis revealed that: (1) Fuji II LC released significantly more fluoride than Fuji II for both triturated (P = 0.005) and hand-mixed (P < 0.005); (2) the triturated Fuji II released significantly more fluoride than the hand-mixed (P = 0.02); and (3) the hand-mixed Fuji II LC released more fluoride than the triturated, but was not statistically significant (P = 0.16).
Brooks
E S
ES
Office of Academic Planning and Development, Baylor College of Dentistry-TAMUS, Dallas, TX 75266-0677, USA.
Miller
B H
BH
Nakajima
H
H
Guo
I
I
D000704:Analysis of Variance; D002327:Cariostatic Agents / Q000008:administration & dosage*; D003793:Dental Restoration, Permanent / Q000295:instrumentation / Q000379:methods*; D004339:Drug Compounding / Q000295:instrumentation / Q000379:methods; D005069:Evaluation Studies as Topic; D005459:Fluorides / Q000008:administration & dosage* / Q000737:chemistry; D005899:Glass Ionomer Cements / Q000737:chemistry*; D019279:Resin Cements / Q000737:chemistry; D012117:Resins, Synthetic / Q000737:chemistry; D018709:Statistics, Nonparametric
D002327:Cariostatic Agents; C079765:Fuji II LC cement; D005899:Glass Ionomer Cements; D019279:Resin Cements; D012117:Resins, Synthetic; C084541:Fuji glass-ionomer lining cement; D005459:Fluorides