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PubMed1998

The durability of adhesion to phosphoric acid etched, wet dentin substrates.

OBJECTIVE: The purpose of this study was to investigate the influence of remaining non-resin-impregnated, phosphoric acid demineralized dentin upon the long-term durability of specimens that were wet-bonded to bovine dentin substrates. METHODS: Prepared bovine dentin samples were etched with 65% phosphoric acid then rinsed with water and kept wet during application of 5 wt% 4-methacryloyloxyethyl trimellitate anhydride (4-META) in acetone primer. This was followed by application of a photocured dentin-bonding agent consisting of 4-methacryloyloxyethyl trimellitate anhydride/triethyleneglycol dimethacrylate-camphorquinone/N-phenylglycine (4-META/TEGDMA-CQ/NPG). The tensile bond strength (TBS) of bonded specimens was determined after immersion in 37 degrees C water for various time intervals. Generated data were analyzed for statistical significance by one-way ANOVA and Duncan's New Multiple Range Test (p < 0.05). The dentin side of the tensile-load-fractured specimens was examined under optical and scanning electron microscopes (SEM). RESULTS: TBS decreased from 6.6 +/- 1.0 MPa after 1-day water immersion to 3.4 +/- 1.7 MPa after 1 month of water immersion. After 6 months of water immersion, TBS was found to be 3.9 +/- 0.9 MPa and this decreased to 2.0 +/- 1.0 MPa for specimens immersed in water for 1 year, a statistically significant difference (p < 0.05). Optical microscopic and SEM observations disclosed failure patterns within demineralized, non-resin-impregnated dentin that increased with the period of water immersion. SIGNIFICANCE: The bond durability to wet dentin was poor when demineralized dentin was not resin-impregnated, resulting in exposure of collagen fibrils which hydrolyzed during long periods of water immersion.

Acid Etching, Dental↗
PubMed2000

Transmucosal delivery systems for calcitonin: a review.

The commercial availability of peptides and proteins and their advantages as therapeutic agents have been the basis for tremendous efforts in designing delivery systems for such agents. The protection of these agents from biological fluids and physiological interactions is crucial for the treatment efficacy. One such agent is salmon calcitonin, a 32 amino-acid polypeptide hormone used in the treatment of bone diseases such as Paget's disease, hypercalcemia and osteoporosis. Researchers have studied different routes to deliver salmon calcitonin more effectively, including nasal, oral, vaginal and rectal delivery. These systems are designed to protect the polypeptide from the biological barriers that each delivery route imposes. Oil-based and polymer-based delivery systems are discussed.

Acrylic Resins↗
PubMed1999

PLGA nanoparticles prepared by nanoprecipitation: drug loading and release studies of a water soluble drug.

The nanoprecipitation technique for preparation of nanoparticles suffers the drawback of poor incorporation of water soluble drugs. The aim of this study was therefore to assess various formulation parameters to enhance the incorporation of a water soluble drug (procaine hydrochloride) into poly(dl-lactide-co-glycolide) (PLGA) nanoparticles prepared by this technique. Approaches investigated for drug incorporation efficiency enhancement included the influence of aqueous phase pH, replacement of procaine hydrochloride with procaine dihydrate and the inclusion of excipients: poly(dl-lactide) (PLA) oligomers, poly(methyl methacrylate-co-methacrylic acid) (PMMA-MA) or fatty acids into the formulation. The nanoparticles produced were submicron size (<210 nm) and of low polydispersity. It was found that an aqueous phase pH of 9.3, replacement of procaine hydrochloride with procaine dihydrate and the incorporation of PMMA-MA, lauric and caprylic acid into the formulation could enhance drug incorporation efficiency without the size, morphology and nanoparticle recovery being adversely influenced. For instance changing the aqueous phase pH from 5.8 to 9.3 increased nanoparticle recovery from 65.1 to 93.4%, drug content from 0.3 to 1.3% w/w and drug entrapment from 11.0 to 58.2%. However, the presence of high ratios of lauric acid and procaine dihydrate in the formulation adversely affected the morphology and size of the nanoparticles. Also, PLA oligomers were not considered a feasible approach since it decreased drug entrapment from 11.0 to 8.4% and nanoparticle recovery from 65.1 to 19.6%. Drug release from nanoparticles appears to consist of two components with an initial rapid release followed by a slower exponential stage. This study has demonstrated that formulation variables can be exploited in order to enhance the incorporation of a water soluble drug into PLGA nanoparticles by the nanoprecipitation technique.

Buffers↗
PubMed2007

Role of stimuli-sensitive polymers in protein refolding: alpha-amylase and CcdB (controller of cell division or death B) as model proteins.

Alginate, a calcium-sensitive polymer, could carry out simultaneous purification and refolding of 8 M urea/100 mM dithiothreitol (DTT) denatured and thermally denatured alpha-amylase present in a commercial preparation. Activity recoveries of 80 and 70% in the former and the latter cases, respectively, were obtained. The fluorescence spectra showed refolding, and PAGE showed the absence of any aggregates in the refolded preparation. As another example, Eudragit S-100, a pH-sensitive poly(methyl methacrylate), was used to refold CcdB (controller of cell division or death B) protein. Initial experiments with wild-type (WT) CcdB showed that Eudragit bound and precipitated (upon lowering the pH to 4.0) CcdB quantitatively from the latter's aqueous solution. The bioconjugate showed DNA gyrase inhibition activity of CcdB and could be recycled. The inclusion bodies of CcdB mutant CcdB-17P were solubilized in 8 M urea/100 mM dithiothreitol. This preparation could be refolded by precipitation with Eudragit. The fluorescence and CD spectra showed that protein refolding has occurred.

Alginates↗
PubMed1998

Leached components from dental composites in oral simulating fluids and the resultant composite strengths.

The aim of this study was to analyse the leached moieties of dental composites after storage in ethanol and organic acids of plaque and further evaluate the resultant effect on the diametral tensile strength (DTS) of the composites. Three commercial composites were used: Bis-GMA-based Z100, Bis-GMA/UDMA-based Heliomolar, and Bis-MPEPP-based Marathon One. The solutions used were: 99.9% acetic acid, 99% propionic acid and 75% ethanol. Specimens (4 mm diam. x 2 mm thick) were stored at 37 degrees C in 3 mL of solution for up to 30 days. Gas chromatography/mass spectrometry was used to characterize the leached moieties and DTS of the specimens after immersion was evaluated. Data were analysed using ANOVA and Tukey LSD test. The eluted substances were not all the same in different solutions and composites but mostly increased with immersion time, and included diluents (TEGDMA and decamethacrylate) and some additives, such as an ultra-violet stabilizer (TINUVINP), plasticizers (dicyclohexyl phthalate and bis(2-ethylhexyl) phthalate), initiator (triphenyl stibine), coupling agent (gamma-methacryloxypropyl trimethoxysilane), and phenyl benzoate. The chief polymerizing monomers were not found. More kinds of components were found in the acetic acid and ethanol groups studied. The fewest kinds and quantities of leached moieties were found for Bis-GMA specimens and then Bis-GMA/UDMA ones, most of which are diluent agents. Bis-MPEPP specimens leached the most substances, which were composed mostly of a short phenyl group chain structure. The BisGMA composite showed the highest DTS (54.8 +/- 5.7 MPa), which was not greatly affected by the length of storage. Bis-GMA/UDMA (36.2 +/- 6.8 MPa) and Bis-MPEPP (26.1 +/- 4.5 MPa) composites were significantly reduced (P < 0.05) after 30 days storage in the ethanol (35-50%), in the propionic acid (25-30%), and in the acetic acid (40-60%). Irreversible processes such as the leaching of components occur in fluids simulating an oral environment, which may contribute to irreversible material degradation, especially for non-Bis-GMA-based composites.

Acetates↗
PubMed2004

Evaluation and comparison of five matrix excipients for the controlled release of acrivastine and pseudoephedrine.

For treatment of allergic rhinitis, acrivastine with pseudoephedrine in Semprex-D conventional capsules requires dosing every 6-8 hours. This study was designed to develop a controlled release matrix tablet of acrivastine and pseudoephedrine and evaluate 5 different matrix excipients for their in vitro controlled-release profiles. Compritol 888ATO, Eudragit RS, Methocel K100M, Polyox WSR301 and Precirol ATO5 were used alone or in varying combinations for the formulation of controlled release matrix tablets. In vitro drug dissolution and mathematical modeling were used to characterize drug release rate and extent. All tablet formulations yielded quality matrix preparations with satisfactory tableting properties. Due to the aqueous solubility of pseudoephedrine and the size of the dose, none of the matrix excipients used alone prolonged drug release significantly to meet the desired twice-daily administration frequency. The use of two excipients in combination, however, significantly decreased the dissolution rate of both active ingredients. A combined lipid-based Compritol and hydrophilic Methocel produced optimal controlled drug release for longer than 8 hours for both acrivastine and pseudoephedrine.

Canada↗
PubMed1988

Adhesion to dentin by means of Gluma resin.

In its present version, the Gluma system for bonding restorative resin to dentin involves the application of an enamel bonding agent prior to the composite resin. Conceivably, pretreating the dentin with solutions of amino acids, and incorporating camphorquinone and selected methacrylic monomers into the Gluma adhesive would nullify the need for the enamel bonding agent. A bond strength to dentin of 13.4 MPa was obtained in the control experiment. Using a solution of pyruvic acid and glycine as pretreatment, and an optimized adhesive mixture containing glutaraldehyde, HEMA, BIS-GMA, camphorquinone, and water, bond strengths to dentin of 14.5 MPa and to enamel of 23.3 MPa were obtained. Thus, the new Gluma bonding system gave acceptable bond strengths without the prior application of enamel bonding agents.

Adhesiveness↗
PubMed1991

An in vivo and in vitro study of the loss of plasticizer from soft polymer-gel materials.

Polymer-gel materials used as short-term denture soft linings are blended with plasticizers to lower the glass transition temperature (Tg). A lower Tg allows for greater polymer chain mobility, thus producing a more flexible material. The present work evaluated the loss of plasticizers due to leaching both in vivo and in vitro. Two commercial denture soft-lining materials (A and B) were tested. These were both poly(ethyl methacrylate) polymers, blended with alcohol and phthalate esters. A clinical study was conducted in which patients wore, sequentially, dentures bearing (on separate occasions) each of the two soft-polymer lining materials. The two materials A and B were randomly assigned for each of ten patients and were worn for 14 and 30 days, respectively. With one exception, patients wore dentures with both lining materials, for a total of 19 clinical evaluations. The plasticizer loss occurring during the clinical trial was determined by GC analysis from the initial and terminal day sampling of plasticizer content of the soft polymer-gel materials. The results of this analysis were compared with results obtained from an in vitro leachability study by use of sink conditions in water at 37 degrees C for the same two commercial soft polymers conducted over the same time periods of 14 and 30 days. The results indicated that a higher loss of plasticizer occurred in vivo, compared with the in vitro tests for 17 of the 19 clinical evaluations. The average plasticizer lost in vivo from material A at 14 days was 122 +/- 58 mg/g, and for material B at 30 days it was 33 +/- 27 mg/g.(ABSTRACT TRUNCATED AT 250 WORDS)

Acrylic Resins↗
PubMed1993

Modified surface-active monomers for adhesive bonding to dentin.

PMGDM, a PMDM-type adhesive monomer, was synthesized from pyromellitic dianhydride and glycerol dimethacrylate. Only the para isomer of PMDM, a solid, is used in dental adhesives. The adhesive monomer PMGDM is a liquid and consists of a mixture of para- and meta isomers. This study shows that PMGDM has several advantages over PMDM. For example, the adhesive can be applied at a greater thickness, and additives and/or additional initiators for improved curing can be incorporated. Use of the liquid monomer PMGDM also provided a convenient means of varying the thickness of the adhesive layer between dentin and composite. The adhesive bonds were tested in both shear and tensile modes. PMDM was used as the control. The reliability of the bonds, as judged from the Weibull modulus and Weibull characteristic strength, was improved by (1) use of more concentrated solutions of PMGDM adhesive, (2) use of an adhesive thickness of about 25 microns, and (3) modification of PMGDM with a diluent monomer which is expected to enhance the degree of cure and/or the dentin-wetting properties of the adhesive resin.

Adhesives↗
PubMedDate not supplied

2-year Clinical evaluation of sodium hypochlorite treatment in the restoration of non-carious cervical lesions: a pilot study.

This pilot study evaluated the effect of removing acid-etch-exposed dentin collagen on the clinical performance of composite restorations of noncarious cervical lesions placed using 2 different adhesive systems. Fifty-six restorations were placed in 14 subjects, each subject receiving at least 4 restorations. No cavity preparation or mechanical retention form was used. The variables tested were: 1) dentin treatment prior to application of the adhesive (acid-etch only vs acid-etch and collagen removal) and 2) type of adhesive (acetone- vs ethanol-based). For the acid-etch only groups, enamel and dentin were etched with 37% phosphoric acid for 15 seconds, rinsed and blot dried. Prime & Bond 2.1 (Dentsply Caulk) or Single Bond (3M ESPE) was applied and light-cured according to the manufacturer's instructions. For the acid-etch and collagen removal groups, the enamel and dentin were etched and rinsed in the same manner and a 10% sodium hypochlorite (NaOCl) solution was applied for 60 seconds and rinsed before adhesive application. Filtek Z-250 (3M ESPE) was applied to all specimens and light-cured according to the manufacturer's instructions, and the restorations were finished and polished immediately. The restorations were evaluated for pre- and post-operative sensitivity, retention, marginal staining and secondary caries at baseline, 12 and 24 months after placement, using modified USPHS criteria. Data were analyzed using the Kruskal-Wallis and Wilcoxon statistical tests (p=0.05). At 24 months, the retention rates for Prime & Bond 2.1 with and without NaOCl pretreatment were 80% and 63%, respectively. The corresponding retention rates for Single Bond were 70% and 90%. Marginal staining was minimal. Statistical analyses revealed no significant differences at any time interval between groups for retention or marginal staining. No post-operative sensitivity or secondary caries was detected during the study.

Acetone↗
PubMed2000

Field-emission scanning electron microscopy of resin-dentin interface morphology of seven dentin adhesive systems.

PURPOSE: The purpose of this study was to evaluate the resin-dentin interface morphology of 7 resin-based dentin adhesive systems (Solid Bond, EBS-Multi, PermaQuik, One Coat Bond, Gluma One Bond, Prime & Bond NT/NRC, and Clearfil Liner Bond 2V). MATERIALS AND METHODS: Fourteen dentin disks 1.0 mm thick were obtained from superficial occlusal dentin of extracted human third molars, and finished with wet 600-grit silicon carbide paper. Two dentin disks were bonded using each of the adhesives above according to the manufacturers' instructions, and a thin layer of flowable resin composite was applied. The specimens were kept in tap water for 24 h at 37 degrees C, and then assigned to one of two observational techniques: a fracture technique and an acid-base technique. Fracture technique: shallow grooves were cut, fixed in 10% buffered formalin, and dehydrated in an ascending ethanol series up to 100%, critical-point dried, and fractured along the prepared grooves. Acid-base technique: the specimens were embedded in epoxy resin, sectioned through the center, polished with diamond paste down to 0.25-micron particle size, and treated with 10% orthophosphoric acid for 10 s and 5% sodium hypochlorite for 5 min. All the specimens were mounted on aluminum stubs, gold sputter coated, and observed using field-emission scanning electron microscopy (FE-SEM). RESULTS: All the dentin adhesive systems showed hybrid layer formation, but the thickness varied depending on the bonding system used. The self-etching priming systems (Prime & Bond NT/NRC and Clearfil Liner Bond 2V) showed the thinnest hybrid layer at 1 to 2 microns, whereas the "single-bottle" system (Gluma One Bond) exhibited the thickest hybrid layer at 8 to 16 microns. CONCLUSION: The ultramorphological structures of dentin bonding systems are determined by the composition of each system. Characterization of the interface of the adhesive system using the fracture technique provides additional information regarding the pattern of resin infiltration in some dentin bonding systems.

Adhesives↗
PubMed2002

The influence of hygroscopic expansion of resin-based restorative materials on artificial gap reduction.

PURPOSE: This study compared the effect of water sorption on the extent of marginal gap reduction in two resin-modified glass-ionomer cements (RMGICs), two giomers, two compomers, and two resin composites over a twelve-week storage period. MATERIALS AND METHODS: Artificial gaps were created in 160 borosilicate glass cylinders. One-half of the internal surface of each cylinder was blocked out with wax and the other half was sandblasted. The bonding surface was further treated with 4% hydrofluoric acid, rinsed, and then coated with silane. After removal of the wax, one coat of dentin adhesive was applied to the silane-treated surface of the cylinder, briefly air dried and light cured. Eight light-cured restorative materials were placed incrementally: Vitremer (V), Fuji II LC (FJ), Beautifil (B), Reactmer Paste (R), Compoglass F (C), F2000 (F), Filtek Z250 (Z), and Tetric-Ceram (T). For each material, ten specimens were stored in deionized water (W), and ten (control) in nonaqueous silicone fluid (O) at 37 degrees C. The dimension of the same maximum gap created in each specimen was repeatedly measured at 0, 1, 2, 4, 6, 8, 10, and 12 weeks. RESULTS: R-W exhibited extensive hygroscopic expansion that resulted in cracking of 40% of glass cylinders after the 2nd week and 70% after the 4th week. One-way ANOVA of the other seven water groups showed significant differences (p < 0.001) among gap widths measured at different time intervals in V-W, FJ-W, C-W, F-W. Both RMGICs had the most significant gap reduction during the first week (p < 0.001). Both compomers exhibited delayed water-sorption characteristics, with more significant gap reduction observed in C-W. B-W was similar to the two resin composites Z-W and T-W and exhibited the least gap reduction. After the first week, there were no significant differences in the percentage reduction in marginal gaps for any of the groups (p > 0.05). CONCLUSION: Marginal gap reduction that results from water sorption is more extensive and rapid in RMG-ICs, followed by compomers, whereas composites are relatively stable. Reactmer Paste exhibits rapid and extensive expansion and should probably be avoided in tooth preparations that involve thin unsupported enamel.

Acid Etching, Dental↗
PubMed2002

Clinical evaluation of two adhesive composite cements for the suppression of dentinal cold sensitivity.

STATEMENT OF PROBLEMS: Postoperative cold sensitivity after the cementation of indirect restorations with composite cements has been reported frequently but not scientifically documented. PURPOSE: This controlled clinical study was designed to simulate the dentin/composite cement interface immediately after cementation of a cast restoration. The desensitizing capabilities of a composite cement that contains a self-etching, dual-polymerizing resin adhesive system were compared with those of a composite cement that use phosphoric acid etching followed by a single-bottle, light-activated primer/resin-based adhesive. MATERIAL AND METHODS: The hypersensitive root surfaces of selected teeth were randomized to receive 1 of 3 treatments: coating with a self-etching adhesive (Linkmax) and its respective cement, coating with a conventionally etched adhesive (RelyX ARC) and its cement, or no treatment (negative control). The sample size was 22. Dentin sensitivity was ascertained with an accurate cold testing device that slowly decreased in temperature. Tooth sensitivity was measured both immediately and at 7 days after placement. Two-way analysis of variance and Fisher's least significant difference test (P<.05) were used to determine whether significant differences existed as a function of treatment type or time. RESULTS: Immediately after placement, the self-etching adhesive and its respective cement resulted in more suppression of cold sensitivity than no treatment (control); with Linkmax treatment, the temperature at which teeth responded was reduced by 8.4 degrees C. The conventionally etched adhesive and its cement reduced the temperature at which teeth responded by 9.4 degrees C. After 1 week, these temperature reductions were 7.0 degrees C and 4.3 degrees C, respectively. Untreated controls at the 2 intervals showed a mean decrease in sensitivity to cold of 3.6 degrees C and 4.1 degrees C. Statistical analysis showed type of composite cement to be a significant factor. CONCLUSION: Within the limitations of this study and in comparison to untreated control teeth, Linkmax treatment resulted in a significant reduction in tooth root sensitivity over 1 week (P=.02), whereas RelyX ARC did not (P=.066).

Acid Etching, Dental↗
PubMedDate not supplied

Evaluation of 24-hour shear bond strength of resin composite to porcelain according to surface treatment.

PURPOSE: The purpose of the present in vitro study was to examine shear bond strengths of resin composite to porcelain according to surface treatment. MATERIALS AND METHODS: One hundred eight feldspathic porcelain blocks were prepared. Specimens were divided into nine surface treatment groups: sandblasting with 50- or 110-microm Al2O3, acid etching with hydrofluoric acid, applying silane agent, and combinations of these treatments. Microhybrid resin composite was condensed and light cured for 40 seconds on the porcelain specimens, which were then stored in distilled water at 37 degrees C for 24 hours before mechanical testing. RESULTS: The bond strengths were significantly different according to one-way ANOVA. The lowest bond strength was observed in the silane group (4.09 MPa); the highest bond strengths were observed with acid etching + silane (11.97 MPa) and sandblasting with 50-microm Al2O3 + acid etching + silane (12.34 MPa) (no significant difference between groups). CONCLUSION: Acid etching with 9.6% hydrofluoric acid gel or sandblasting with 50- or 110-microm Al2O3 particles alone did not provide adequate bond strength. Silane agent was effective in increasing the shear bond strength of resin composite to porcelain after sandblasting or acid etching. Porcelain treatment with a combination of 50-microm Al2O3 air abrasion, 9.6% hydrofluoric acid, and silane agent provided higher bond strengths than treatment with any of these procedures alone.

Acid Etching, Dental↗
PubMedDate not supplied

Effects of adhesive liner and provisional cement on the bond strength of nickel/chrome/beryllium alloy cemented to dentin.

OBJECTIVE: Treating teeth with adhesive agents before placing a provisional restoration can prevent tooth sensitivity. This study evaluated the bond strength of resin cements to dentin treated with 2 adhesive agents and 2 provisional cements. METHODS AND MATERIALS: Extracted human molars were prepared by exposing dentin and were treated with either Prime & Bond NT or Clearfil SE Bond. After a simulated impression technique, the teeth were provisionalized with either a eugenol or noneugenol temporary cement. Teeth were cleaned for bonding by either mechanical removal of the cement or use of an acid conditioner. Panavia F and Calibra resin cements were used to cement nickel/chrome/beryllium alloy to the tooth surfaces, and the specimens were debonded. Mean shear bond strengths for each group were calculated. RESULTS: Mean shear bond strengths ranged from 26.6 +/- 5.8 MPa for Calibra bonded to dentin treated with Prime & Bond NT, a noneugenol cement, and mechanically cleaned, to 10.6 +/- 4.4 MPa for Panavia F bonded to unlined (no adhesive) dentin treated with a eugenol cement and mechanically cleaned. Of the 14 groups tested, significant differences were observed related to the adhesives and resin cements. Both temporary cements reduced the bond to dentin not treated with a resin adhesive. Use of an acid conditioner for cleaning the temporary cement also reduced bond strengths in all groups. CONCLUSIONS: Placement of a dentin adhesive before provisionalization may prevent the temporary cement from affecting the bond of the final resin cement to the tooth. For the products used in this study, use of phosphoric acid to clean the tooth surface is not recommended.

Cementation↗
PubMedDate not supplied

[Concentration of hepatitis A and B virus antigens using water-soluble polymers].

A possibility of using reversibly sedimented polymeric system for the concentration of hepatitis A and B virus antigen has been demonstrated. As polymeric systems, tetrasole-containing polyelectrolytes and interpolymeric complex polymethacryl acid-poly-1-vinylpyrrolidone were used, capable of sedimenting in acid medium and dissolving in media with the neutral pH.

Antigens, Viral↗
PubMed2000

Self-help interventions for smoking cessation.

BACKGROUND: Many smokers give up smoking on their own, but provision of materials giving advice and information may assist them and increase the number who quit successfully. OBJECTIVES: The aims of this review were to determine the effectiveness of different forms of self-help materials, compared with no treatment and with other minimal contact strategies; the effectiveness of adjuncts to self-help, such as computer generated feedback, telephone hotlines and pharmacotherapy; and the effectiveness of approaches tailored to the individual compared with non-tailored materials. SEARCH STRATEGY: We searched the Cochrane Tobacco Addiction Group trials register. Date of the most recent search September 1999. SELECTION CRITERIA: We included randomised trials of smoking cessation with follow-up of at least six months, where at least one arm tested a self-help intervention. We defined self-help as structured programming for smokers trying to quit without intensive contact with a therapist. DATA COLLECTION AND ANALYSIS: We extracted data in duplicate on the type of subjects, the nature of the self-help materials, the amount of face to face contact given to subjects and to controls, outcome measures, method of randomisation, and completeness of follow-up. The main outcome measure was abstinence from smoking after at least six months follow-up in patients smoking at baseline. We used the most rigorous definition of abstinence in each trial, and biochemically validated rates when available. Where appropriate, we performed meta-analysis using a fixed effects model. MAIN RESULTS: We identified forty-five trials. Twenty seven compared self-help materials to no intervention or tested materials as an adjunct to advice. In nine trials in which self-help was compared to no intervention there was a pooled effect which just reached statistical significance (odds ratio 1.23, 95% confidence interval 1.02 to 1.49). There was no evidence of benefit from adding self-help materials to face to face advice, or to nicotine replacement therapy. There was evidence from eight trials using materials which were tailored for the characteristics of individual smokers that such personalised materials were more effective than standard materials (odds ratio 1.41, 95% confidence interval 1.14 to 1.75). Adding follow-up telephone calls from counsellors also appeared to increase quitting (odds ratio 1.62, 95% confidence interval 1.33 to 1.97). One trial of offering access to a hotline also showed an effect. REVIEWER'S CONCLUSIONS: Self-help materials may provide a small increase in quitting compared to no intervention. There is no evidence that they have an additional benefit over other minimal interventions such as advice from a health care professional, or nicotine replacement therapy. There is evidence that materials tailored for individual smokers are more effective.

Behavior Therapy↗