Resin bonding to root canal dentin: effect of the application of an experimental hydrophobic resin coating after an all-in-one adhesive.
OBJECTIVE
Based on the hypothesis the application of a low-viscosity hydrophobic resin coating improves the bond of all-in-one adhesive, the purpose of the study was to evaluate the bond strength of four adhesive systems to bovine root dentin using the push-out test method.


METHODS
The root canals of 32 bovine roots (16 mm) were prepared to a length of 12 mm using a FRC Postec Plus preparation drill. The specimens were allocated into four groups according to the adhesive system used: (Group 1) All-in-one Xeno III; (Group 2) All-in-one Xeno III+ScotchBond Multi-Purpose Plus Adhesive; (Group 3) Simplified Etch & Rinse One Step Plus; and (Group 4) Multi-Bottle Etch & Rinse All-Bond 2. A fiber-reinforced composite retention post was reproduced using an additional silicon impression and fabricated with DuoLink resin cement. The root specimens were treated with the selected adhesive systems, and the resin posts were luted in the canals with DuoLink resin cement. Each root specimen was cross sectioned into four samples (+/-1.8 mm in thickness), and the post sections were pushed-out to determine the bond strength to dentin.


RESULTS
Group 2 (2.9+/-1.2) was statistically higher than Group 1 (1.1+/-0.5) and Group 3 (1.1+/-0.5). Groups 1 and 3 showed no statistically significant difference while Group 4 (2.0+/-0.7) presented similar values (p>0.05) to Groups 1, 2, and 3 [(one-way analysis of variance (ANOVA)] and Tukey test, a=0.05).


CONCLUSIONS
The hypothesis was accepted since the application of the additional layer of a low-viscosity bonding resin improved the bond of the all-in-one adhesive. Further studies must be conducted to evaluate the long-term bond.
Lombardo
Geraldo H L
GH
São Jose dos Campos Dental School at São Paulo State University in Sao Jose dos Campos, SP, Brazil. geraldolombardo@hotmail.com
Souza
Rodrigo O A
RO
Michida
Silvia M A
SM
de Melo
Renata Marques
RM
Bottino
Marco Antonio
MA
Valandro
Luiz Felipe
LF
D000134:Acid Etching, Dental / Q000379:methods; D000268:Adhesiveness; D000818:Animals; D002417:Cattle; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D003786:Dental Pulp Cavity / Q000648:ultrastructure*; D003804:Dentin / Q000648:ultrastructure*; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D011176:Post and Core Technique / Q000295:instrumentation; D019279:Resin Cements / Q000737:chemistry*; D018915:Root Canal Preparation / Q000379:methods; D013314:Stress, Mechanical
D003188:Composite Resins; D017220:Dentin-Bonding Agents; C431350:Duo-Link; D008689:Methacrylates; D019279:Resin Cements; C425844:Scotchbond Multi-Purpose Plus; C487957:Xeno III; C100742:All-Bond 2