In vitro evaluation of fluoride release of orthodontic bonding adhesives.
OBJECTIVE
To assess the fluoride release from adhesives used for bonding in orthodontics.


METHODS
Six bonding agents were evaluated: five adhesives (Biofix, Fill Magic Orthodontic, EagleBond, Orthobond, and Transbond XT) and one resin-reinforced glass-ionomer cement (Fuji Ortho LC), the latter serving as a control. Ten samples of each adhesive were stored in containers with 5 mL of deionized distilled water at 37°C. Fluoride release was measured with an ion-specific electrode. Readings were taken periodically for a total of 33 days. On day 28, all samples were immersed in a 0.221% sodium fluoride solution for 5 minutes to assess their recharge potential. Descriptive statistics were calculated for the fluoride release rates of each material. ANOVA with multiple comparisons and the Kruskal-Wallis tests (P < .05) were used to assess differences between the groups.


RESULTS
All adhesives released significant amounts of fluoride (P < .05). During the first day, Biofix released the highest amount of fluoride, followed by Fuji Ortho LC, which also showed the highest fluoride release from day 7 to day 33. The fluoride release from Biofix and Fuji Ortho LC decreased by the third day to 40% of its original value. All other adhesives maintained their fluoride release with only small fluctuations.


CONCLUSIONS
All the materials released significant amounts of fluoride, with Biofix having the highest release in the first 3 days and Fuji Ortho LC over the total length of the experiment.
Southwest Bahia University UESB, Bahia, Brazil.
Matheus Melo
MM
Pithon
Rogerio Lacerda
RL
dos Santos
Antonio Carlos
AC
de Oliveira Ruellas
Lincoln Issamu
LI
Nojima
Eduardo Franzotti
EF
Sant'anna
D000042:Absorption; D000180:Acrylic Resins / Q000737:chemistry; D000538:Aluminum Silicates / Q000737:chemistry; D002327:Cariostatic Agents / Q000737:chemistry*; D003188:Composite Resins / Q000737:chemistry; D003738:Dental Cements / Q000737:chemistry*; D005459:Fluorides / Q000737:chemistry*; D005899:Glass Ionomer Cements / Q000737:chemistry; D006801:Humans; D006863:Hydrogen-Ion Concentration; D017736:Ion-Selective Electrodes; D008422:Materials Testing; D016910:Orthodontic Brackets; D011100:Polyglycolic Acid / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D012969:Sodium Fluoride / Q000737:chemistry; D013696:Temperature; D013997:Time Factors; D014867:Water / Q000737:chemistry
D000180:Acrylic Resins; D000538:Aluminum Silicates; D002327:Cariostatic Agents; D003188:Composite Resins; D003738:Dental Cements; C481898:Fill Magic; C095451:Fuji Ortho LC; D005899:Glass Ionomer Cements; D019279:Resin Cements; C477790:Transbond XT; D014867:Water; D011100:Polyglycolic Acid; D012969:Sodium Fluoride; D005459:Fluorides