Lilliam M. Pinzon

Factors affecting in vitro bond strength of bonding agents to human dentin.

Four generations of total-etch (fourth, fifth) and self-etching (sixth, seventh) bonding agents for use with resin composites are commercially available in the United States. Innovations in bonding agents include: filled systems, release of fluoride and other agents, unit dose, self-cured catalyst, option of etching with either phosphoric acid or self-etching primer, and pH indicators. Factors that can affect in vitro bond strength to human dentin include substrate (superficial dentin, deep dentin; permanent versus primary teeth; artificial carious dentin), phosphoric acid versus acidic primers, preparation by air abrasion and laser, moisture, contaminants, desensitizing agents, astringents, and self-cured restorative materials. This article reviews studies conducted at the Houston Biomaterials Research Center from 1993 to 2003. Results show that in vitro bond strengths can be reduced by more than 50% when bonding conditions are not ideal.

Bond strength of adhesives to dentin contaminated with smoker’s saliva

The purpose of this study was to determine the effects of contamination with smoker’s and non-smoker’s saliva on the bond strength of resin composite to superficial dentin using different adhesive systems. The interfacial structure between the resin and dentin was evaluated for each treatment using environmental scanning electron microscopy (ESEM). Freshly extracted human molars were ground with 600-grit SiC paper to expose the superficial dentin. Adhesives [One-Up-Bond-F-Plus (OUFP) and Adper-Prompt-L-Pop (APLP)] and resin composite (TPHSpectrum) were bonded to the dentin (n = 8/group, 180 total specimens) under five surface conditions: control (adhesive applied following manufacturers’ instructions); saliva, then 5-s air dry, then adhesive; adhesive, saliva, 5-s air dry; adhesive, saliva, 5-s water rinse, 5-s air dry (ASW group); and adhesive, saliva, 5-s water rinse, 5-s air dry, reapply adhesive (ASWA group). After storage in water at 37°C for 24 h, the specimens were debonded under tension at a speed of 0.5 mm/min. ESEM photomicrographs of the dentin/adhesive interfaces were taken. Mean bond strength ranged from 8.1 to 24.1 MPa. Fisher’s protected least significant difference (P = 0.05) intervals for critical adhesive, saliva, and surface condition differences were 1.3, 1.3, and 2.1 MPa, respectively. There were no significant differences in bond strength to dentin between contamination by smoker’s and nonsmoker’s saliva, but bond strengths were significantly different between adhesive systems, with OUFP twice as strong as APLP under almost all conditions. After adhesive application and contamination with either smoker’s or nonsmoker’s saliva followed by washing and reapplication of the adhesive (ASWA group), the bond strength of both adhesive systems was the same as that of the control group.

The global burden of oral diseases in pediatric HIV‐infected populations: a workshop report

OBJECTIVES To achieve a comprehensive understanding about the global burden of oral diseases in HIV-infected children and to identify research needs. MATERIALS AND METHODS A literature search was conducted in PubMed (2009-2014) to address five questions: (i) prevalence of oral diseases in HIV-infected compared with uninfected children, (ii) impact of oral diseases on quality of life, (iii) effect of antiretroviral exposure in utero on craniofacial and dental development, (iv) important co-infections and antiretroviral complications, and (v) value of atraumatic restorative treatment. RESULTS Studies showed a high prevalence of dental caries in HIV-infected children but the relationship between HIV infection and dental caries remains unclear. Also quality of life needs further investigation supported by better study designs and improvement of the instruments used. Up-to-date evidence suggested long-term harms associated with in utero antiretroviral exposure were minor but would require long-term follow-up through National Registries. The reviews also revealed the wide spectrum of metabolic disease due to antiretroviral therapy and co-infections such as tuberculosis. Finally, atraumatic restorative technique appears to be a simple and safe technique to treat dental caries but outcomes need further evaluation. CONCLUSIONS The impact of antiretroviral therapy in HIV-infected children has raised novel challenging questions in the field of oral health warranting future research.