PMID- 21859315
OWN - NLM
STAT- MEDLINE
DCOM- 20111229
LR  - 20131121
IS  - 0361-7734 (Print)
IS  - 0361-7734 (Linking)
VI  - 36
IP  - 5
DP  - 2011 Sep-Oct
TI  - Adhesion of resin composite to hydrofluoric acid-exposed enamel and dentin in 
      repair protocols.
PG  - 545-53
LID - 10.2341/10-312-L [doi]
AB  - Intraoral repairs of ceramic fixed-dental-prostheses (FDP) often include cervical 
      recessions that require pretreatment of the exposed tooth surfaces either before 
      or after the ceramic is conditioned with hydrofluoric (HF) acid gel. The sequence 
      of repair protocol may cross-contaminate the exposed etched enamel or dentin 
      surfaces during the application or rinsing process and thereby affect the 
      adhesion. This study evaluated the influence of HF acid gel with two 
      concentrations on bond strengths of composite to enamel and dentin. Human third 
      molars (N=100, n=10 per group) with similar sizes were selected and randomly 
      divided into 10 groups. Flat surfaces of enamel and dentin were created by wet 
      ground finishing. Before or after the enamel (E) or dentin (D) was conditioned 
      with phosphoric acid (P), substrate surfaces were conditioned with either 9.5% HF 
      (HF(9.5)) or 5% HF (HF(5)). Subsequently, a bonding agent (B) was applied. The 
      experimental groups by conditioning sequence were as follows where the first 
      letter of the group abbreviation represents the substrate (E or D) followed by 
      the acid type and concentration: group 1 (EPHF(9.5)), group 2 (EPHF(5)), group 3 
      (EHF(9.5)P), group 4 (EHF(5)P), group 5 (DPHF(9.5)), group 6 (DPHF(5)), group 7 
      (DHF(9.5)P), and group 8 (DHF(5)P). Group 9 (EPB) and group 10 (DPB) acted as the 
      control groups. Repair resin was adhered incrementally onto the conditioned 
      enamel and dentin in polyethylene molds. Each layer was photo-polymerized for 40 
      seconds. All specimens were thermocycled (x1000, 5 degrees -55 degrees C) and subjected to shear 
      test (universal testing machine, 1 mm/min). Specimens that debonded during 
      thermocycling were considered as 0 MPa. The bond strength data were analyzed 
      using Kruskal-Wallis test and failure types using the chi-square test (alpha=0.05). 
      Overall, the bond results (MPa) were lower on dentin than on enamel (p<0.01). EPB 
      (25.6 +/- 6.6) and DPB (20.2 +/- 4.9) control groups showed significantly higher 
      results than those of other groups (p<0.05). While higher mean bond strengths 
      were obtained in group 1 (EPHF(9.5)) (11.5 +/- 2.1) and group 2 (EPHF(5)) (7.3 +/- 
      0.6), lower results were obtained when HF acid gels were applied prior to 
      phosphoric acid (EHF(9.5)P: 5.0 +/- 1.1, EHF(5)P: 3.6 +/- 0.1) (p<0.05). On dentin, 
      the results were the lowest in group 8 (DHF(5)P: 1.5 +/- 1.6), being significantly 
      lower than those of group 5 (DPHF(9.5)) (p<0.05). Scanning electron microscope 
      (SEM) images revealed predominantly mixed failures with less than half of the 
      composite left on both enamel and dentin surfaces (64 out of 80) (p<0.05), 
      indicating that in general, adhesion was not ideal. Contamination of the enamel 
      or dentin surfaces with HF acid gel impairs the bond strength of composites. 
      Considering both the bond strength results and failure types, when dental tissues 
      are to be repaired next to ceramic, application of phosphoric acid before HF acid 
      gel application can be recommended. HF acid gel concentration did not influence 
      the results except on enamel.
FAU - Saracoglu, A
AU  - Saracoglu A
AD  - Department of Prosthodontics, University of Ege, Izmir, Turkey.
FAU - Ozcan, M
AU  - Ozcan M
FAU - Kumbuloglu, O
AU  - Kumbuloglu O
FAU - Turkun, M
AU  - Turkun M
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PT  - Randomized Controlled Trial
DEP - 20110822
PL  - United States
TA  - Oper Dent
JT  - Operative dentistry
JID - 7605679
RN  - 0 (Composite Resins)
RN  - 0 (Dental Cements)
RN  - 0 (Dental Materials)
RN  - 0 (Excite cement)
RN  - 0 (Methacrylates)
RN  - 0 (Phosphoric Acids)
RN  - 0 (Tetric EvoCeram)
RN  - 8MDF5V39QO (Sodium Bicarbonate)
RN  - 9011-14-7 (Polymethyl Methacrylate)
RN  - E4GA8884NN (phosphoric acid)
RN  - H0G9379FGK (Calcium Carbonate)
RN  - RGL5YE86CZ (Hydrofluoric Acid)
MH  - Acid Etching, Dental/*methods
MH  - Adhesiveness
MH  - Calcium Carbonate/chemistry
MH  - Composite Resins/*chemistry
MH  - *Dental Bonding
MH  - Dental Cements/chemistry
MH  - Dental Enamel/*ultrastructure
MH  - Dental Materials/*chemistry
MH  - *Dental Prosthesis Repair
MH  - Dental Stress Analysis/instrumentation
MH  - Dentin/*ultrastructure
MH  - Humans
MH  - Hydrofluoric Acid/*chemistry
MH  - Materials Testing
MH  - Methacrylates/chemistry
MH  - Microscopy, Electron, Scanning
MH  - Phosphoric Acids/chemistry
MH  - Polymerization
MH  - Polymethyl Methacrylate/chemistry
MH  - Sodium Bicarbonate/chemistry
MH  - Stress, Mechanical
MH  - Temperature
MH  - Time Factors
EDAT- 2011/08/24 06:00
MHDA- 2011/12/30 06:00
CRDT- 2011/08/24 06:00
PHST- 2011/08/24 06:00 [entrez]
PHST- 2011/08/24 06:00 [pubmed]
PHST- 2011/12/30 06:00 [medline]
AID - 10.2341/10-312-L [doi]
PST - ppublish
SO  - Oper Dent. 2011 Sep-Oct;36(5):545-53. doi: 10.2341/10-312-L. Epub 2011 Aug 22.