Real-time measurement of dentinal fluid flow during amalgam and composite restoration.
OBJECTIVE
This study examined changes in the dentinal fluid flow (DFF) during restorative procedures and compared permeability after restoration among restorative materials and adhesives.


METHODS
A class 1 cavity was prepared and restored with either amalgam (Bestaloy), or composite (Z-250) with one of two etch-and-rinse adhesives (Scotchbond MultiPurpose: MP and Single Bond 2: SB) or one of two self-etch adhesives (Clearfil SE Bond: CE and Easy Bond: EB) on an extracted human third molar which was connected to a sub-nanoliter fluid flow measuring device (NFMD) under 20 cm water pressure. DFF was measured from the intact tooth state through the restoration procedures to 30 min after restoration, and re-measured at 3 and 7 days post-restoration.


RESULTS
Inward flow during cavity preparation was followed by outward flow after preparation. In amalgam restoration, the outward flow changed into an inward flow during amalgam filling, which was followed by a slight outward flow after finishing. In composite restoration, MP and SB showed an inward flow and outward flow for the rinsing and drying steps, respectively. Application of a hydrophobic bonding resin in the MP and CE systems caused a decrease in the flow rate. Air-drying of solvent for the CE and EB systems caused a sudden outward flow, whereas light-curing of the adhesive and composite caused an abrupt inward flow.


CONCLUSIONS
Each restorative step clearly changed the direction and the rate of the DFF during restoration, which could be well identified with NFMD.
Kim
Sun-Young
SY
Department of Conservative Dentistry and Dental Research Institute, School of Dentistry, Seoul National University, 28-2 Yeongeon-Dong, Jongro-Gu, Seoul 110-749, South Korea.
Ferracane
Jack
J
Kim
Hae-Young
HY
Lee
In-Bog
IB
D000134:Acid Etching, Dental / Q000379:methods; D000388:Air; D017438:Bisphenol A-Glycidyl Methacrylate; D003188:Composite Resins; D055117:Curing Lights, Dental; D003723:Dental Amalgam; D003737:Dental Cavity Preparation / Q000145:classification; D003764:Dental Materials; D003793:Dental Restoration, Permanent / Q000145:classification / Q000379:methods*; D003806:Dentin Permeability / Q000502:physiology; D017220:Dentin-Bonding Agents; D019234:Dentinal Fluid / Q000378:metabolism*; D004867:Equipment Design; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D044085:Microfluidics / Q000295:instrumentation; D036103:Nanotechnology / Q000295:instrumentation; D019279:Resin Cements; D012997:Solvents; D013997:Time Factors
C438313:Clearfil SE Bond; D003188:Composite Resins; D003764:Dental Materials; D017220:Dentin-Bonding Agents; C444701:Filtek Z250; D019279:Resin Cements; C084018:Scotchbond Multi-Purpose; D012997:Solvents; C115612:single bond; D017438:Bisphenol A-Glycidyl Methacrylate; D003723:Dental Amalgam