A delayed hypersensitivity reaction to dentine primer in the guinea-pig

A comprehensive in vitro study on the performance of two different strategies to simplify adhesive bonding

Objective

The purpose of this study is to compare the bonding performance and mechanical properties of two different resin composite cements using simplified adhesive bonding strategies.

Materials and methods

Shear bond strength of two resin composite cements (an adhesive cement: Panavia V5 [PV5] and a self‐adhesive cement: RelyX Universal [RUV]) to human enamel, dentin, and a variety of restorative materials (microfilled composite, composite, polymer‐infiltrated ceramic, feldspar ceramic, lithium disilicate and zirconia) was measured. Thermocycle aging was performed with selected material combinations.

Results

For both cements, the highest shear bond strength to dentin was achieved when using a primer (PV5: 18.0 ± 4.2 MPa, RUV: 18.2 ± 3.3 MPa). Additional etching of dentin reduced bond strength for RUV (12.5 ± 4.9 MPa). On enamel, PV5 achieved the highest bond strength when the primer was used (18.0 ± 3.1 MPa), while for RUV etching of enamel and priming provided best results (21.2 ± 6.6 MPa). Shear bond strength of RUV to restorative materials was superior to PV5. Bonding to resin‐based materials was predominantly observed for RUV.

Conclusions

While use of RUV with the selective‐etch technique is slightly more labor intensive than PV5, RUV (with its universal primer) displayed a high‐bonding potential to all tested restorative materials, especially to resin.

Clinical significance

For a strong adhesion to the tooth substrate, PV5 (with its tooth primer) is to be preferred because etching with phosphoric acid is not required. However, when using a wide range of varying restorative materials, RUV with its universal primer seems to be an adequate option.

Improving predictive capacity of the Amino acid Derivative Reactivity Assay test method for skin sensitization potential with an optimal molar concentration of test chemical solution

The Amino acid Derivative Reactivity Assay (ADRA) is a convenient and effective in chemico test method for assessing covalent binding of test chemicals with protein-derived nucleophilic reagents as a means of predicting skin sensitization potential. Although the original molar-concentration approach to ADRA testing was not suitable for testing multiconstituent substances of an unknown composition, a weight-concentration approach that is suitable for such substances was developed, which also led to the realization that test chemical solutions prepared to molar concentrations higher than the original 1 mM would reduce false negative results as well as enhance predictive capacity. The present study determined an optimal molar-concentration that achieves even higher predictive capacity than the original ADRA. Eight chemicals that were false negatives when tested with 1 mM test chemical solutions were retested with test chemical solutions between 2 and 5 mM, which showed 4 mM to be the optimal molar-concentration for ADRA testing. When 82 chemicals used in the original development were retested with 4 mM test chemical solutions, false negative results were reduced by four. When an additional 85 chemicals used to evaluate the weight-concentration approach to ADRA were retested, the results essentially replicated those obtained with 0.5 mg/ml test chemical solutions and gave 10 fewer false negatives than original ADRA with 1 mM solutions. A comparison of these results for 136 chemicals showed that ADRA testing with 4 mM solutions achieved a four percentage point improvement in accuracy over original ADRA and a two percentage point improvement over DPRA testing.

A toxicological review of the ethylene glycol series: Commonalities and differences in toxicity and modes of action

This review summarizes the hazards, exposure and risk that are associated with ethylene glycols (EGs) in their intended applications. Ethylene glycol (EG; CAS RN 107-21-1) and its related oligomers include mono-, di-, tri-, tetra-, and penta-EG. All of the EGs are quickly and extensively absorbed following ingestion and inhalation, but not by the dermal route. Metabolism involves oxidation to the mono- and dicarboxylic acids. Elimination is primarily through the urine as the parent compound or the monoacid, and, in the case of EG, also as exhaled carbon dioxide. All EGs exert acute toxicity in a similar manner, characterized by CNS depression and metabolic acidosis in humans and rodents; the larger molecules being proportionally less acutely toxic on a strict mg/kg basis. Species differences exist in the metabolism and distribution of toxic metabolites, particularly with the formation of glycolic acids and oxalates (OX) from EG and diethylene glycol (DEG); OX are not formed to a significant degree in higher ethylene glycols. Among rodents, rats are more sensitive than mice, and males more sensitive than females to the acute and repeated-dose toxicity of EG. The metabolic formation of glycolic acid (GA), diglycolic acid (DGA), and OX are associated with nephrotoxicity in humans and rodents following single and repeated exposures. However, physiological and metabolic differences in the rate of formation of GA, DGA and OX and their distribution result in EG and DEG causing embryotoxicity in rats, but not rabbits. This rodent-specific sensitivity indicates that EG and its higher oligomers are not anticipated to be embryotoxic in humans at environmentally relevant doses. None of the compounds present developmental toxicity concerns at doses that do not also cause significant maternal toxicity, nor do any of the EGs cause adverse effects on fertility. The EGs are neither genotoxic nor carcinogenic. A read-across matrix is presented, which considers the common and distinct toxicological properties of each compound. It is concluded that EGs pose no risk to human health as a result of their intended use patterns.

Effect of increased exposure times on amount of residual monomer released from single-step self-etch adhesives

BACKGROUND

The aim of this study was to evaluate the effect of increased exposure times on the amount of residual Bis-GMA, TEGDMA, HEMA and UDMA released from single-step self-etch adhesive systems.

METHODS

Two adhesive systems were used. The adhesives were applied to bovine dentin surface according to the manufacturer's instructions and were polymerized using an LED curing unit for 10, 20 and 40 seconds (n = 5). After polymerization, the specimens were stored in 75% ethanol-water solution (6 mL). Residual monomers (Bis-GMA, TEGDMA, UDMA and HEMA) that were eluted from the adhesives (after 10 minutes, 1 hour, 1 day, 7 days and 30 days) were analyzed by high-performance liquid chromatography (HPLC). The data were analyzed using 1-way analysis of variance and Tukey HSD tests.

RESULTS

Among the time periods, the highest amount of released residual monomers from adhesives was observed in the 10th minute. There were statistically significant differences regarding released Bis-GMA, UDMA, HEMA and TEGDMA between the adhesive systems (p<0.05). There were no significant differences among the 10, 20 and 40 second polymerization times according to their effect on residual monomer release from adhesives (p>0.05).

CONCLUSIONS

Increasing the polymerization time did not have an effect on residual monomer release from single-step self-etch adhesives.

Evaluation of HEMA released from four different adhesive systems by HPLC

PURPOSE

This study evaluated the elution of 2-hydroxyethyl methacrylate (HEMA) from 4 different adhesives, using high-performance liquid chromatography (HPLC).

MATERIALS AND METHODS

The adhesives were applied on a bovine dentin surface and polymerized using an LED curing unit (n=5). After polymerization, specimens were stored in 75% ethanol solution (6 mL). Residual HEMA that was eluted from adhesives (after 10 minutes, 1 hour, 24 hours, 7 days and 30 days) was analyzed using HPLC. Statistical analyses were performed using 1-way ANOVA, Tukey HSD test and paired 2-sample t-test.

RESULTS

There were statistically significant differences among adhesive systems for the cumulative released HEMA and among the time periods (p<0.05). Clearfil SE Bond showed the highest amount of HEMA released, while Easy Bond showed the lowest. Among the time periods, the highest eluted HEMA value was detected in 10 minutes for all adhesives, and elution continued for up to 30 days.

CONCLUSIONS

The HEMA eluted from adhesives was in different amounts, and the elution continued for a long time. The amount of eluted HEMA from adhesives used in this study was not viewed as critical for toxic reactions in biological tissues.

Five-year clinical performance of a HEMA-free one-step self-etch adhesive in noncarious cervical lesions

OBJECTIVES

The objective of this randomized controlled trial was to evaluate the clinical performance of a 2-hydroxyethyl methacrylate (HEMA)-free one-step adhesive.

MATERIALS AND METHODS

Two hundred sixty-seven cervical lesions in 52 patients were restored with the composite Gradia Direct (GC), bonded with either the one-step self-etch adhesive G-Bond (GC) or the three-step etch-and-rinse adhesive Optibond FL (Kerr) in a random order. The restorations were evaluated for retention, marginal integrity, marginal discoloration, and caries occurrence after 5 years. Specific statistics were used to account for the clustered data (multiple restorations per patient).

RESULTS

The clinical success rate for G-Bond (87.4 %) was not significantly different from that of Optibond FL (90.9 %). Both adhesives showed progressive marginal deterioration, but G-Bond exhibited more small enamel defects and marginal discoloration, and unlike previous recalls, several restorations failed because of deep microleakage. Large sclerotic lesions were a significant risk factor for retention loss with G-Bond. Irrespective of the adhesive, almost all restorations with retention loss were located in the lower jaw.

CONCLUSION

After 5 years of clinical service, restorations bonded with the HEMA-free one-step adhesive did not need repair or replacement more often than those with the three-step etch-and-rinse adhesive, and both adhesives had a high retention rate (>90 %). There were indications that G-Bond did not (self-)etch enough in some clinical situations, as G-Bond exhibited more incisal defects and marginal discolorations, and sclerotic lesions were at higher risk of retention loss.

CLINICAL RELEVANCE

The clinical performance of the HEMA-free one-step adhesive was clinically acceptable after 5 years.

Methyl methacrylate and respiratory sensitization: a critical review

Methyl methacrylate (MMA) is a respiratory irritant and dermal sensitizer that has been associated with occupational asthma in a small number of case reports. Those reports have raised concern that it might be a respiratory sensitizer. To better understand that possibility, we reviewed the in silico, in chemico, in vitro, and in vivo toxicology literature, and also epidemiologic and occupational medicine reports related to the respiratory effects of MMA. Numerous in silico and in chemico studies indicate that MMA is unlikely to be a respiratory sensitizer. The few in vitro studies suggest that MMA has generally weak effects. In vivo studies have documented contact skin sensitization, nonspecific cytotoxicity, and weakly positive responses on local lymph node assay; guinea pig and mouse inhalation sensitization tests have not been performed. Cohort and cross-sectional worker studies reported irritation of eyes, nose, and upper respiratory tract associated with short-term peaks exposures, but little evidence for respiratory sensitization or asthma. Nineteen case reports described asthma, laryngitis, or hypersensitivity pneumonitis in MMA-exposed workers; however, exposures were either not well described or involved mixtures containing more reactive respiratory sensitizers and irritants. The weight of evidence, both experimental and observational, argues that MMA is not a respiratory sensitizer.

HPLC analysis of HEMA released from two different adhesive systems

OBJECTIVES

The aim of this study was to evaluate in vitro elution of 2-Hydroxyethyl methacrylate (HEMA) from two different adhesive systems, used in two dual polymerized resin cements for bonding of ceramic restoration by high performance liquid chromatography (HPLC).

METHODS

Twenty freshly extracted caries and restoration free molar teeth used in this study. Standardized Class I preparations were prepared in all teeth. A lithium disilicate based (IPS Empress Esthetic; Ivoclar) ceramic inlays were cemented with one of the dual polymerized resin cements (RelyX ARC; 3M ESPE or Nexus 2; Kerr) that have two different adhesive systems (Single Bond; 3M ESPE, Optibond Solo Plus; Kerr). After cementation, specimens were stored in 75% ethanol solution. HPLC was used to analyze the amount of HEMA in the solution (after 10 min, 1 h, 24 h, 3, 7, 14, and 21 days). Two-way analysis of variance and Tukey HSD tests were used to evaluate the results (p < 0.05).

RESULTS

There were statistically significant differences between adhesive systems according to the amount of released HEMA (p < 0.01) and also among time periods (p < 0.01). The amount of HEMA eluted from Optibond Solo Plus was significantly higher than Single Bond. The total amount of monomers was the highest after 21 days (p < 0.01).

CONCLUSIONS

In the case of adhesive systems, Optibond Solo Plus showed the highest amount of HEMA. The amount of HEMA eluted from adhesive systems influenced by the time.

Guinea Pig Maximization Test of Tri-ethylene Glycol Mono-methacrylate

The aim of this study was to evaluate tri-ethylene glycol mono-methacrylate (TEGMA) in terms of dermatological allergic reaction using a Guinea Pig Maximization Test. Skin reaction was evaluated according to the criteria of International Contact Dermatitis Research Group. TEGMA, as a constituent in new primers, has been reported to contribute to a priming ability similar to that of highly purified glyceryl mono-methacrylate (GM). In this study, it was found that its adverse effect was less than that of 2-hydroxy ethyl methacrylate (2-HEMA), but similar to that of highly purified GM. In conclusion, it was anticipated that TEGMA would hereafter replace 2-HEMA as a primer, as it posed a lower risk of triggering dermatological allergic reaction.

Final report of the safety assessment of methacrylate ester monomers used in nail enhancement products

Methacrylate ester monomers are used in as artificial nail builders in nail enhancement products. They undergo rapid polymerization to form a hard material on the nail that is then shaped. While Ethyl Methacrylate is the primary monomer used in nail enhancement products, other methacrylate esters are also used. This safety assessment addresses 22 other methacrylate esters reported by industry to be present in small percentages as artificial nail builders in cosmetic products. They function to speed up polymerization and/or form cross-links. Only Tetrahydrofurfuryl Methacrylate was reported to the FDA to be in current use. The polymerization rates of these methacrylate esters are within the same range as Ethyl Methacrylate. While data are not available on all of these methacrylate esters, the available data demonstrated little acute oral, dermal, or i.p. toxicity. In a 28-day inhalation study on rats, Butyl Methacrylate caused upper airway irritation; the NOAEL was 1801 mg/m3. In a 28-day oral toxicity study on rats, t-Butyl Methacrylate had a NOAEL of 20 mg/kg/day. Beagle dogs dosed with 0.2 to 2.0 g/kg/day of C12 to C18 methacrylate monomers for 13 weeks exhibited effects only in the highest dose group: weight loss, emesis, diarrhea, mucoid feces, or salivation were observed. Butyl Methacrylate (0.1 M) and Isobutyl Methacrylate (0.1 M) are mildly irritating to the rabbit eye. HEMA is corrosive when instilled in the rabbit eye, while PEG-4 Dimethacrylate and Trimethylolpropane Trimethacrylate are minimally irritating to the eye. Dermal irritation caused by methacrylates is documented in guinea pigs and rabbits. In guinea pigs, HEMA, Isopropylidenediphenyl Bisglycidyl Methacrylate, Lauryl Methacrylate, and Trimethylolpropane Trimethacrylate are strong sensitizers; Butyl Methacrylate, Cyclohexyl Methacrylate, Hexyl Methacrylate, and Urethane Methacrylate are moderate sensitizers; Hydroxypropyl Methacrylate is a weak sensitizer; and PEG-4 Dimethacrylate and Triethylene Glycol Dimethacrylate are not sensitizers. Ethylene Glycol Dimethacrylate was not a sensitizer in one guinea pig study, but was a strong sensitizer in another. There is cross-reactivity between various methacrylate esters in some sensitization tests. Inhaled Butyl Methacrylate, HEMA, Hydroxypropyl Methacrylate, and Trimethylolpropane Trimethacrylate can be developmental toxicants at high exposure levels (1000 mg/kg/day). None of the methacrylate ester monomers that were tested were shown to have any endocrine disrupting activity. These methacrylate esters are mostly non-mutagenic in bacterial test systems, but weak mutagenic responses were seen in mammalian cell test systems. Chronic dermal exposure of mice to PEG-4 Dimethacrylate (25 mg, 2 x weekly for 80 weeks) or Trimethylolpropane Trimethacrylate (25 mg, 2 x weekly for 80 weeks) did not result in increased incidence of skin or visceral tumors. The carcinogenicity of Triethylene Glycol Dimethacrylate (5, 25, or 50%) was assessed in a mouse skin painting study (50 microl for 5 days/week for 78 weeks), but was not carcinogenic at any dose level tested. The Expert Panel was concerned about the strong sensitization and crossor co-reactivity potential of the methacrylate esters reviewed in this report. However, data demonstrated the rates of polymerization of these Methacrylates were similar to that of Ethyl Methacrylate and there would be little monomer available exposure to the skin. In consideration of the animal toxicity data, the CIR Expert Panel decided that these methacrylate esters should be restricted to the nail and must not be in contact with the skin. Accordingly, these methacrylate esters are safe as used in nail enhancement products when skin contact is avoided.

Bonding efficacy and side effects of the high purity glyceryl mono-methacrylate

The purpose of this study was to examine the efficacy of experimentally developed high purity glyceryl mono-methacrylate (GM) as a dentine primer and to evaluate the possibility of allergic reaction. The efficacy of experimental dentine primers was evaluated by measuring the polymerization contraction gap width and the tensile bond strength. Allergic reaction was evaluated by the guinea-pig maximization test. The skin reaction was evaluated according to the criteria of the International Contact Dermatitis Research Group. Contraction gap formation was completely prevented and the tensile bond strength was not significantly affected by priming with GM on high-purity GM. The allergic response decreased when high-purity GM was employed as the challenger. It was concluded that the clinical use of the high-purity GM is beneficial as the delayed allergic reaction could be avoided with no detrimental effect on the dentine bonding.

Evidence for bacterial causation of adverse pulpal responses in resin-based dental restorations

The widespread use of resin and resin-monomers for bonding of dental restorations to dentin has occurred because of a fundamental shift in the view that injury to the pulp is induced by restorative procedures. While, for many years, the toxic effects of restorative materials were thought to be of crucial importance in the development of adverse pulpal responses, the key role of bacterial leakage at the restoration-tooth interface is now well-recognized. Consequently, if optimal conditions for the preservation of pulpal health are to be ensured, dental restorations should provide an impervious seal against the surrounding tooth structure. However, polymerization shrinkage and contraction stresses induced during setting, as well as a variety of technical difficulties encountered during the clinical operation, often produce less than perfect results. Therefore, modern restorative procedures involving resin and resin-bonded restoratives must still rely on the ability of the pulp to cope with the injurious elements to which it may be exposed during and after the procedure. This review examines factors that may govern the pulp's response to restorative procedures that involve adhesive technologies. An assessment is made of the risks involved as far as the continued vital function of the pulp is concerned. It is concluded that an intact, although thin, wall of primary dentin often enables the pulp to overcome both toxic material effects and the influences of bacterial leakage. In contrast, the pulp may not do equally well following capping of open exposures with resin composites. A dearth of controlled clinical studies in this area of dentistry calls for confirmation that pulpal health prevails over the long term following the use of total-etch and resin-bonding techniques.

The effect of curing regime on the release of hydroxyethyl methacrylate (HEMA) from resin-modified glass-ionomer cements

This study investigated the effects of degree of cure and specimen maturation on the release of HEMA from four resin-modified glass-ionomer cements. Disc specimens were light-cured for either the manufacturers' recommended time (MRT) for that material, or were under-cured (irradiated for 0.5 MRT), over-cured (1.5 MRT) or allowed to dark-cure (0 MRT). Specimens were matured in the mould at 37 degrees C until set or for 10 min, 40 min or 24 h prior to immersion in distilled water (at 37 degrees C) for 4 h. The HEMA release was determined by measuring the HEMA concentration in the storage water by HPLC. Vitremer, Fuji II LC and Fuji Lining LC set without light-curing (0 MRT) in less than 6 min and these specimens released low levels of HEMA (approximately 1, 7 and 4% of the included HEMA, respectively). Dark-cured Vitrebond took 15 min to set and the HEMA release was high (approximately 50% of the included HEMA) indicating that the material had only set by the acid-base reaction. HEMA release from light-cured Vitremer or Vitrebond was not affected by under- or over-curing but release from Fuji II LC was reduced by over-curing (1.5 MRT). Under-curing Fuji Lining LC caused a significant increase in HEMA release. Specimen maturation times of 10 min, or longer, had little effect on the measured HEMA release. All the materials released HEMA into their storage solutions. In order to minimise HEMA release, resin-modified glass-ionomers should always be cured for at least the manufacturers' recommended time at thicknesses no greater than the maximum recommended.

The adverse effect of commercial dentine-bonding systems on the skin of guinea pigs

It was widely known that 2-hydroxyethyl methacrylate (2-HEMA) can cause contact dermatitis. Commercially available dentine primers and dentine bonding agents that contain 2-HEMA are widely used. The purpose of this study was to investigate the cumulative irritation and delayed hypersensitivity caused by commercial dentine bonding systems when applied to the skin of guinea pigs. We have concluded that almost no dentine bonding systems cause cumulative irritation, but some commercially available dentine bonding systems may produce delayed hypersensitivity.

Component release from light-activated glass ionomer and compomer cements

The purpose of this study was to identify and quantify any component released from seven commercially available light-cured or resin-modified glass ionomer and compomer cements. Twenty-one separate cylindrical stainless steel moulds 6 mm in diameter and 1.0 mm deep were filled with one of seven glass ionomer or compomer cements, light activated and then immediately immersed in separate containers of distilled water. Water samples were retrieved over a time period of up to 30 days and retained for analysis. An occlusal cavity 6 mm in diameter was prepared in extracted human third molar teeth with a remaining dentin thickness of 1.6-2.0 mm. A polypropylene chamber was attached to the cemento-enamel junction of each tooth to contain 1 mL of distilled water. Ten teeth were each filled with one of three cements and light activated. Water samples (eluates) were retrieved over a period of time. All samples were analysed by high performance liquid chromatography. Only one component, hydroxyethyl methacrylate (HEMA), was detected in the eluates from both tooth and mould samples. Analysis of diffusion of the HEMA through dentin showed a relatively sustained movement into the pulp space during the first day, with exponential decline thereafter. Our data show that HEMA was released from all of the light activated glass ionomer cements studied and from the compomer, both directly into water and through dentin. This release may be relevant both to the risk of adverse pulpal responses in patients and to the risk of allergy in patients and dental personnel.

Dental materials: 1995 literature review

This critical review of the published literature on dental materials for the year 1995 has been compiled by the Dental Materials Panel of the United Kingdom. It continues the series of annual reviews started in 1973 and published in the Journal of Dentistry. Emphasis has been placed upon publications which report upon the materials science or clinical performance of the materials. The review has been divided by accepted materials classifications (fissure sealants, glass polyalkenoate cements, resin composites, dentine bonding, dental amalgam, endodontic materials, casting alloys, investment materials, resin-bonded bridges and ceramo-metallic restorations, all ceramic restorations, denture base and soft lining materials, impression materials, dental implants, orthodontic materials and biomechanics). Three hundred and thirty articles published in 68 titles have been reviewed.

Effects of an aminomethacrylate on epithelial cell lipid metabolism

Methacrylates can affect cell functions by surfactant-like effects or by altering cell lipid composition. Dimethylaminoethyl methacrylate (DMAEMA), an activator widely used in visible-light polymerized dental resins has been shown to elute readily into aqueous environments. The current study examined the metabolism of this material by oral epithelial cells (HCP) and its subsequent effects on cell lipids. Cells were plated in culture medium, then exposed to DMAEMA in the presence of 14C-acetate, a precursor which labeled the cell lipids. Other cultures were prelabeled with radioisotope, then exposed to DMAEMA. After incubation, the cell lipids were extracted and separated by TLC. Radioactive lipids were located and quantitated. Exposure of the cells to DMAEMA resulted in decreased synthesis of cholesterol with a concomitant increase in sterol precursors. Cholesterol esters and triacylglycerides also increased. Among the polar lipids, phosphatidyl choline (PC) and phosphatidyl ethanolamine (PE) decreased in response to DMAEMA. However, dimethylphosphatidyl ethanolamine (DMPE), a precursor of PC not detectable in control cultures, accumulated to a significant extent in cells exposed to DMAEMA. Furthermore, changes in PC and DMPE levels persisted in the cells for at least 48 h after removal of the DMAEMA. The results indicate that DMAEMA produces alterations in the relative amounts of several cellular neutral and polar lipids. Such alterations, especially of the normal phospholipid composition, along with an alteration in cellular cholesterol, could result in altered membrane-associated cell functions.

Bioavailability of components of resin-based materials which are applied to teeth

Chemical components of many materials used in dental practice can move into the local biophase, where they can have beneficial or adverse effects. The strongest indirect evidence that components of resin-based materials used in dentistry can move into the biophase are the many reports of allergic dermatitis in dental personnel. Direct measurement of component release has shown that triethylene glycol dimethacrylate (TEGDMA), hydroxyethyl methacrylate (HEMA), and, in the case of some orthodontic cements, bis-glycidyl methacrylate and benzoyl peroxide can move into an aqueous medium from a range of resin-based materials which are applied to teeth as part of oral care. In the case of resin composite restorations, HEMA and TEGDMA are available in microgram quantities via the salivary surface in the minutes and hours after clinical placement and via dentin and pulp in the hours and days after placement. Fortunately, moderate thickness of dentin protects pulp tissue against local toxicity. There are no data which suggest that systemic toxicity is a risk with any of these materials. There are some case reports of allergic responses to the monomers in patients, but the incidence of such responses appears at present to be much lower than that in dental personnel.

Review of dental materials citations: Part B, July to December 1995

OBJECTIVE

A lag of many months occurs between journal issue publication and updates to electronic databases. The objective of this literature analysis was to identify and categorize all of the dental materials citations in biomedical journals that were published from July 1995 through December 1995.

METHODS

Seventeen primary and 51 secondary journals were searched using their tables of contents to detect and record dental materials publications from July to December of 1995. Those journals that were typically rich in dental materials articles were classified as primary ones. Citations were categorized into 17 topics and divided into subsections. The review excluded case reports, most literature related primarily to dental implants, and most articles on biomedical materials used outside of the field of general dentistry.

RESULTS

The greatest number of citations was related to topics of dentin bonding and resin-based restorative filling materials (composites and glass ionomers). There was no major change in the number of dental materials publications per year reported from 1993 (n = 786) to 1995 (n = 751).

SIGNIFICANCE

This citation list provides a comprehensive resource for use by academicians and researchers to bridge the gap between initial publication and access to electronic searching methods for major databases.