Allergic contact dermatitis in dentistry

The Use of Acrylate Polymers in Dentistry

The manuscript aimed to review the types of acrylate polymers used in dentistry, as well as their chemical, physical, mechanical, and biological properties. Regarding their consistency and purpose, dental acrylate polymers are divided into hard (brittle), which includes acrylates for the production of plate denture bases, obturator prostheses, epitheses and maxillofacial prostheses, their repairs and lining, and soft (flexible), which are used for lining denture bases in special indications. Concerning the composition and method of polymerization initiation, polymers for the production of denture bases are divided into four types: heat-, cold-, light-, and microwave-polymerized. CAD/CAM acrylate dentures are made from factory blocks of dental acrylates and show optimal mechanical and physical properties, undoubtedly better monomer polymerization and thus biocompatibility, and stability of the shape and colour of the base and dentures. Regardless of the number of advantages that these polymers have to offer, they also exhibit certain disadvantages. Technological development enables the enhancement of all acrylate properties to respond better to the demands of the profession. Special attention should be paid to improving the biological characteristics of acrylate polymers, due to reported adverse reactions of patients and dental staff to potentially toxic substances released during their preparation and use.

Occupational Contact Dermatitis in Dental Personnel: A Retrospective Analysis of the North American Contact Dermatitis Group Data, 2001 to 2018

BACKGROUND

Dental personnel are at risk of developing occupational contact dermatitis.

OBJECTIVES

The aims of the study were to determine prevalence of occupational contact dermatitis in dental personnel referred for patch testing and to characterize relevant allergens and sources.

METHODS

The study used a retrospective, cross-sectional analysis of the North American Contact Dermatitis Group (NACDG) data, 2001-2018.

RESULTS

Of 41,109 patients, 585 (1.4%) were dental personnel. Dental personnel were significantly more likely than nondental personnel to be female (75.7% vs 67.4%, P < 0.0001), have occupationally related dermatitis (35.7% vs 11.5%, P < 0.0001), and/or have primary hand involvement (48.6% vs 22.5%, P < 0.0001). More than one quarter of dental personnel (62/585, 27.7%) had 1 or more occupationally related allergic patch test reaction(s). There were 249 occupationally related reactions to NACDG screening allergens, most commonly glutaraldehyde (18.1%), thiuram mix (16.1%), and carba mix (14.1%). The most common sources of NACDG screening allergens were gloves (30.7%), dental materials (26.6%), and sterilizing solutions (13.1%). Seventy-three dental personnel (12.5%) had 1 or more positive patch test reactions to occupationally related allergen(s)/substances not on the screening series. Occupationally related irritant contact dermatitis was identified in 22.2% (n = 130) of dental personnel, most commonly to nonskin soaps/detergents/disinfectants (32.0%).

CONCLUSIONS

Occupational contact dermatitis is common in dental personnel referred for patch testing. Comprehensive testing beyond screening series is important in these patients.

Characterization and toxicity evaluation of air-borne particles released by grinding from two dental resin composites in vitro

OBJECTIVE

The project aims to evaluate whether inhalation of particles released upon grinding of dental composites may pose a health hazard to dentists. The main objective of the study was to characterize the dust from polymer-based dental composites ground with different grain sized burs and investigate particle uptake and the potential cytotoxic effects in human bronchial cells.

METHODS

Polymerized blocks of two dental composites, Filtek™ Z250 and Filtek™ Z500 from 3M™ ESPE, were ground with super coarse (black) and fine (red) burs inside a glass chamber. Ultrafine airborne dust concentration and particle size distribution was measured real-time during grinding with a scanning mobility particle sizer (SMPS). Filter-collected airborne particles were characterized with dynamic light scattering (DLS) and scanning electron microscopy (SEM). Human bronchial epithelial cells (HBEC-3KT) were exposed to the dusts in dose-effect experiments. Toxicity was measured with lactate dehydrogenase (LDH) assay and cell counting kit-8 (CCK8). Cellular uptake was observed with transmission electron microscopy (TEM).

RESULTS

Airborne ultrafine particles showed that most particles were in the size range 15-35 nm (SMPS). SEM analysis proved that more than 80% of the particles have a minimum Feret diameter less than 1 μm. In solution (DLS), the particles have larger diameters and tend to agglomerate. Cell toxicity (LDH, CCK8) is shown after 48 h and 72 h exposure times and at the highest doses. TEM showed presence of the particles within the cell cytoplasm.

SIGNIFICANCE

Prolonged and frequent exposure through inhalation may have negative health implications for dentists.

In vitro effects of dental monomer exposure - Dependence on the cell culture model

Methacrylate monomers are major components of resin-based biomaterials. The polymerization of these materials is never complete, and methacrylates leaking from cured materials cause exposure of patients. Only some selected methacrylates have thoroughly been tested for possible interaction with living cells. In the current study, we compared the effects of 2-hydroxyethyl-methacrylate (HEMA; a carefully studied methacrylate) and hydroxypropyl-methacrylate (HPMA; a scarcely investigated methacrylate). Five cell lines differing in both source and cell type were used. The cells were exposed to methacrylates (1-8 mM). Cell viability, cell death, glutathione levels, reactive oxygen species (ROS), and cell growth pattern were measured. Both methacrylates reduced cell viability, and glutathione depletion was observed in all cell lines. The cell death pattern varied among the cell lines. The ROS levels and cell growth pattern also differed between the cell lines after exposure to methacrylate monomers. No difference between HEMA and HPMA exposures were observed in any of the cell lines. The variation between cell lines shows that the measured methacrylate toxicity depends heavily on the test system chosen. Further, the conformity between HEMA and HPMA effects suggests that the two methacrylates similarly affect living cells.

Introducing career skills for dental students as an undergraduate course at the University of Szeged, Hungary

BACKGROUND

In the last three decades there is a growing recognition in the dental profession that dental education must go beyond teaching the technicalities of dentistry and include professionalism and communication skills that the future dentist may need. Such skills are best taught in a student-centered way. Literature suggests that student-centered elements are difficult to introduce in traditional, teacher-centered curricula. This is especially true in post-communist countries where higher education was under strict state control for decades. The aim of the piece of research presented here was to investigate how difficult it is to introduce a student-centered career skills course in a traditionally teacher-centered dental curriculum.

METHODS

Considering the needs of our final-year dental students and Super's model of career development, we created an undergraduate curricular career skills course running for two semesters in two languages (Hungarian and English). The primary aim of the course is to help students with their career expectations and develop their identity as a professional workforce. The secondary aim is to teach skills that students can use when applying for a job. At the end of the semesters, we assessed our students' satisfaction with various aspects of the course by using a questionnaire. Results were analyzed item-wise and according to the main aspects of the course (i.e., groups of items organized around a particular aspect).

RESULTS

General satisfaction with the course was high, and practical skills training (such as CV and motivation letter writing) got the highest scores. From the answers it appears that the students were the least comfortable with having to deal with their personal values and preferences.

CONCLUSIONS

While it is common for universities to offer various forms of career intervention, to our knowledge, no other university offers a curricular career skills course specifically for dental students. Our student-centered course designed in a problem-based learning framework worked even in a traditionally teacher-centered educational environment, where university students are rarely encouraged to be active participants in courses. By sharing our experience, we would like to encourage our fellow dental educators working in similar environments to devise and offer such courses.

Skin reactions among Bulgarian dental students: A self-report questionnaire survey

BACKGROUND

Dental students are at high risk of developing adverse skin reactions following practical work during the dentistry degree program. They encounter multiple irritants and allergens that may cause skin reactions on exposed parts of the body, notably the hands.

OBJECTIVES

To estimate the prevalence of skin reactions related to the pre-clinical and clinical training courses of the dentistry program and associated risk factors in Bulgarian dental students.

METHOD

A cross-sectional study was performed using a self-report questionnaire.

RESULTS

A total of 467 dental students completed the questionnaire (response 51.8%). The prevalence of self-reported skin symptoms was 21.2%. According to logistic regression analysis, the most important risk factors for work-related skin symptoms were a personal history of atopic dermatitis (odds ratio [OR] 3.92, 95% confidence interval [CI]: 1.99-7.72), allergic rhinoconjunctivitis and/or asthma (OR 1.94, 95%CI: 1.03-3.68), personal history of contact allergy (OR 2.19, 95%CI: 1.06-4.55), and hand washing >16 times a day (OR 2.42, 95%CI: 1.06-5.52).

CONCLUSIONS

The results of this study suggest that work-related skin symptoms are frequent among dental students and indicate the need to establish effective primary preventive programs for occupational skin disorders at a national level.

Glove-Related Allergic Contact Dermatitis

Hand dermatitis is a common condition with a lifetime prevalence of 20%. Glove allergic contact dermatitis (ACD) is a very important dermatitis affecting health care workers, hairdressers, cleaning personnel, kitchen workers, craftsmen, construction workers, laboratory workers, and homemakers. Occupationally related cases may be severe and can result in significant disability. Glove ACD is most commonly due to exposure to rubber accelerators, which are compounds that are added to rubber during production to increase strength and durability. Given the known allergic potential of these compounds, glove manufacturing companies have reformulated gloves leading to the introduction of new rubber allergens. In this review, we will discuss risk factors for glove ACD, both common and uncommon allergens in gloves, common contact allergens that permeate gloves, and patch testing to help uncover the inciting allergen(s).

Knowledge and Awareness towards Occupational Hazards and Preventive Measures among Students and Dentists in Jazan Dental College, Saudi Arabia

AIM:

The present study was aimed to assess the level of awareness and occupational hazards of dental students and professionals who are working at dental college and hospital, Jazan University, Saudi Arabia.

MATERIAL AND METHODS:

Data has been collected through a self-administrated questionnaire with closed questions. The questionnaire consisted of questions on personal information like age, gender, years of experience and awareness of occupational hazards, seminar attendance, safety measures practised, and experience of occupational hazard while in practice. Participants were asked to answer each questionnaire item as “yes” or “no”. The data were analysed with SPSS-Version and P-value was generated.

RESULTS:

Out of the 200 participants, 38.5% were females, and 62% were males. Differences were found significantly high between male and female subjects regarding neck shoulder pain, hand wrist pain, backache, and anxiety and routine use of a surgical cap (P < 0.05). Over 33% of the participants had attended workshops or conferences about the occupational hazards. 12.85% participants reported latex allergy and 74% of the participants vaccinated against Hepatitis B. Significant differences were found in the attitude of general dentists towards the preventive measures against the occupational hazards based on years of experience.

CONCLUSION:

The findings of this study are consistent with the previous studies. Specific psychological concerns related to the conditions and the environment of the practice at dental college and hospital, Jazan University were expressed because the majority of participants were students.

Occupational dermatitis in health care workers evaluated for suspected allergic contact dermatitis

BACKGROUND

Contact dermatitides occur commonly among health care workers (HCWs).

OBJECTIVE

To contrast the atopic status and incidence, location, and final diagnosis of skin diseases afflicting HCWs versus non-HCWs (NHCWs) evaluated for suspicion of allergic contact dermatitis (ACD); and among the population diagnosed with ACD, to compare the incidence and occupational relatedness of allergens found in HCWs with the rates observed in NHCWs.

METHODS

Between July 1, 1994, and May 30, 2014, 2611 patients underwent patch testing by the senior author. Of these, 165 were classified as HCWs based on their primary occupation. Statistical analysis was done using a χ test.

RESULTS

Health care workers were more likely than NHCWs to be women and to have hand dermatitis. Women, but not men, HCWs suffered more irritant contact dermatitis. Health care workers had significantly more work-related ACD, especially to formaldehyde, quaternium-15, 2-bromo-2-nitropropane-1,3-diol, cocamide diethanolamine (DEA), thiuram mix, carba mix, thimerosal, benzalkonium chloride, glutaraldehyde, and bacitracin.

LIMITATIONS

Only patients suspected of having ACD were tested. Our population was geographically limited to metropolitan Kansas City, MO and metropolitan New York, NY.

CONCLUSIONS

Health care workers suffer more from occupational ACD, especially of the hands, than do NHCWs, including to allergens not present on available standard allergen series.

Occupational hazards to dental staff

Dental professionals are predisposed to a number of occupational hazards. These include exposure to infections (including Human Immunodeficiency Virus and viral hepatitis); percutaneous exposure incidents, dental materials, radiation, and noise; musculoskeletal disorders; psychological problems and dermatitis; respiratory disorders; and eye insults. Percutaneous exposure incidents remain a main concern, as exposure to serious infectious agents is a virtual risk. Minimizing percutaneous exposure incidents and their consequences should continue to be considered, including sound infection control practices, continuing education, and hepatitis B vaccination. Basically, for any infection control strategies, dentists should be aware of individual protective measures and appropriate sterilization or other high-level disinfection utilities. Strained posture at work disturbs the musculoskeletal alignment and leads to stooped spine. The stooped posture also involved certain groups of muscles and joints. This may lead to diseases of the musculoskeletal system. Continuous educating and appropriate intervention studies are needed to reduce the complication of these hazards. So, it is important for dentists to remain constantly up-to-date about measures on how to deal with newer strategies and dental materials, and implicates the need for special medical care for this professional group.

Risks with dental materials

OBJECTIVES

Dental materials are among the most used substitutes for biological tissue in the human body. The possible health effects of amalgam have been studied extensively and have sometimes been replaced with other less well-examined materials. The aim was to study the hazards of other dental materials than amalgam.

METHODS

Toxicological information was collected from the Swedish Dental Materials Register 2003 (DentMr). The material safety data sheets (MSDS) included in the DentMR was examined regarding the given composition of the products, the occurrence of CAS-numbers and risk and safety phrases of the substances. Furthermore, complementary information about risk and safety phrases for substances with missing information in the MSDS was collected by using two easily available databases.

RESULTS

There were 482 products that included 377 substances of which 219 could be identified. Only 26% of 219 substances had risk and safety phrases. However, via the Swedish Chemicals Inspectorate Classification Register and the Sigma-Aldrich product register, risk and safety phrases could be found for 37 substances. A literature search indicated that some of the listed substances had possible hazards, e.g. substances with embryotoxic and neurotoxic potential.

SIGNIFICANCE

The information about hazards with dental materials seems insufficiently described in MSDS and there might be materials with side effects unknown to both patients and dental personnel. There is a need for stronger regulation of dental materials, at least substances that the patients will be exposed to for decades.

Occupational hazards in orthodontics: A review of risks and associated pathology

The purpose of this article was to review the occupational hazards related to the practice of orthodontics. A systematic approach was used to include all risks involved in an orthodontic practice. The classification of hazards was based on major sources of risks by system or tissue and by orthodontic office area (dental chair, laboratory, sterilization area, x-ray developing area). Potentially hazardous factors relate to the general practice setting; to specific materials and tools that expose the operator to vision and hearing risks; to chemical substances with known allergenic, toxic, or irritating actions; to increased microbial counts and silica particles of the aerosols produced during debonding; to ergonomic considerations that might have an impact on the provider's muscoleskeletal system; and to psychological stress with proven undesirable sequelae. The identification and elimination of these risk factors should be incorporated into a standard practice management program as an integral part of orthodontic education. Professional organizations can also assist in informing practitioners of potential hazards and methods to deal with them.

The immuno cross-reactivity of gutta percha points

OBJECTIVE

The purpose of this study is to test the postulated immuno cross-reactivity between proteins derived from raw gutta percha (RGP), gutta percha point (GPP) and natural rubber latex (NRL).

METHODS

Antigenicity and cross-reactivity of proteins were determined by the FITkit (FITBiotech, Finland) and ELISA inhibition assays.

RESULTS

Antigenicity of proteins derived from RGP or GPP was not demonstrated. Except for NRL glove extracts, neither extracts from RGP or GPP were reactive in ELISA inhibition assay.

SIGNIFICANCE

There is no immunologic cross-reactivity in vitro between proteins derived from RGP or GPP, and from NRL gloves. Thus, therapeutic use of GPP is unlikely to initiate adverse immuno-reactivity in individuals previously sensitized to NRL proteins.

Women's Occupational Dermatologic Issues

With almost 65 million women in the workforce, their representation in various occupational sectors is crucial, as is their health and safety. Female-dominated occupations in health care and cosmetology along with their potential cutaneous exposures are reviewed. Proper evaluation and management are necessary to minimize the disability that can result from these illnesses.

Potential occupational health problems for dentists in Flanders, Belgium

The aim of this study was to gather data on occupational health effects among Flemish dentists. A questionnaire on various potential health effects was sent out to randomly selected Flemish dentists. Pilot experimental studies were performed on hearing and sensory function of the fingers on small groups of dentists. Audiometric data of both ears, gathered with an interval of 10 years, were analysed. Sensory tests of the fingers were performed for dominant and non-dominant hands in relation to exposure time to (ultra)sonic equipment. Positive responses for the questionnaire were as follows: low back pain, 54% (stress-correlated); vision problems, 52.3% (age-correlated); infections, 9%; allergies, 22.5% (mainly latex); stress level was scored 7 on a scale from 0 to 10; diminished sensitivity of the fingertips, 6% and auditory disorders, 19.6%. Pilot audiometric data showed a hearing loss at 4,000 Hz for the left ear, presumably indicative of occupational noise trauma. The two-point discrimination ability of the dominant hand tended to diminish in line with the number of years of practice. Dentists in Flanders were found to suffer from various health-related problems. More elaborate studies are required to provide more details on the risks for occupational hearing impairment and vibration hand neuropathy and to determine whether the problems described were related to the practice of dentistry.

Residual methyl methacrylate monomer, water sorption, and water solubility of hypoallergenic denture base materials

STATEMENT OF PROBLEM

Denture base materials have the potential to cause irritation and allergic reaction to the oral mucosa. Water sorption and water solubility of denture base resins affect dimensional behavior and denture stability. A correlation between residual monomer and water sorption exists.

PURPOSE

This in vitro study compared the amount of residual monomer, quantity of water sorption, and solubility of 4 denture base materials purported to be hypoallergenic with those of a polymethyl methacrylate-based (PMMA) heat-polymerizing acrylic resin.

MATERIAL AND METHODS

The denture base resins Sinomer (heat-polymerized, modified methacrylate), Polyan (thermoplastic, modified methacrylate), Promysan (thermoplastic, enterephthalate-based), and Microbase (microwave polymerized, polyurethane-based), which are purported to be hypoallergenic, and Paladon 65 (heat-polymerized, methacrylate, control group) were examined. Specimens of each material were tested for residual methyl methacrylate (MMA) monomer (% wt, n=3), amount of water sorption (microg/mm3, n=5) and water solubility (microg/mm3, n=5), according to ISO 1567:2000. The residual MMA monomer concentrations were determined by gas chromatography (GC). The data were analyzed with 1-way ANOVA and the Bonferroni-Dunn multiple comparisons post hoc analysis for each test variable (alpha=.05).

RESULTS

Significantly lower residual MMA monomer was shown for Sinomer and Polyan compared to the PMMA control group (0.90 +/- 0.20% wt, P<.05). Sinomer contained 0.31% +/- 0.00% wt MMA monomer, and Polyan exhibited residual MMA monomer content of 0.44% +/- 0.01% wt. Promysan and Microbase did not contain detectable residual MMA. Water sorption of Promysan (16.21 +/- 0.96 microg/mm3) was significantly lower than Paladon 65 (23.04 +/- 3.13 microg/mm3, P<.0001), whereas water solubility of the hypoallergenic denture base materials (0.34-0.84 +/- 0.05-0.09 microg/mm3) was not significantly lower than the PMMA material (0.40 +/- 0.06 microg/mm3, P>.05). Except for Sinomer, the tested denture base resins passed the requirements of ISO 1567 regarding residual MMA monomer (<2.2% wt). Sinomer failed to comply with the requirements for residual MMA monomer because the manufacturer claimed that the material did not contain any MMA. The tested denture base materials fulfilled the requirements regarding water sorption (<32 microg/mm3) and solubility (<1.6 microg/mm3).

CONCLUSION

The tested hypoallergenic denture base materials exhibited significantly lower residual monomer content than PMMA. Promysan and Microbase showed no detectable residual MMA.

The national survey of adverse reactions to dental materials in the UK: a preliminary study by the UK Adverse Reactions Reporting Project

OBJECTIVE

Dental treatment involves the use of a wide range of materials. Many of the dental materials or their components pose a potential risk to the patient and member of the dental team. Pre-market biocompatibility testing cannot guarantee absolute safety, making monitoring of materials likely to cause an adverse reaction essential. The prevalence of adverse reactions to dental materials amongst dental patients and staff has not been systematically monitored in the UK. This project aims to develop a systematic approach to the evaluation and monitoring of the extent and severity of adverse reactions to dental materials in the UK.

METHOD

Through the distribution of reporting forms to dental surgeries and laboratories in the UK, the ARRP has received 1,075 complete reports relating to adverse reactions seen or experienced by dental staff and patients.

RESULTS

The main findings were that different materials cause adverse reactions to different groups of people. The largest proportion of patient related adverse reactions were reported to be due to metals (n = 175). These were mainly amalgam associated oral lichenoid reactions (n = 124). Dental technicians reported acrylic resin as the causal factor of hand dermatitis in 61% (44 out of a total 72) of cases reported. Finally, dental surgery staff reported gloves as causing hand dermatitis in 75% of cases (398 out of a total 531).

CONCLUSIONS

Different dental materials affect different person groups depending on their exposure to the material. Dental staff are most at risk from an adverse reaction to latex gloves, whereas most reported reactions for patients were due to metals. For dental technicians the biggest danger of an adverse reaction was from acrylic resins. There is a need to continue to raise the awareness among dental professionals of the existence of the Adverse Reactions Reporting Project so as to overcome problems of under-reporting.

Uptake, clearance and metabolism of TEGDMA in guinea pigs

OBJECTIVE

The resin monomer triethyleneglycoldimethacrylate (TEGDMA) is used as a diluent in many resin-based bonding, cementing and direct tooth filling materials.

METHODS

In the present study the uptake and the clearance of 14C-TEGDMA applied via different routes were examined in vivo in guinea pigs. TEGDMA (0.02 mmol/kg by weight labeled with a tracer dose 14C-TEGDMA 0.7Bq/g by weight) was administered by gastric tube or by subcutaneous injection. Urine, feces, and exhaled carbon dioxide were collected for 24h after administration. The animals were killed 24h after the beginning of the experiment and various organs removed and 14C-radioactivity measured.

RESULTS

It was apparent that 14C-TEGDMA was taken up rapidly from the stomach and small intestine after gastric administration and was widely distributed in the body following administration by each of the routes. Clearance from most tissues following gastric and intradermal administration was essentially complete within one day. Low fecal 14C-levels (<1% of the administered dose) and urinary levels of about 15% after 24h were noted with each route of administration. Direct measurement of exhaled carbon dioxide showed that 60-65% of the administered dose of 14C left the body via the lungs during 24h. It is likely that 14C-pyruvate is formed in vivo resulting possibly in the formation of toxic 14C-TEGDMA-intermediates.

SIGNIFICANCE

Despite using a high administered dose, the peak TEGDMA levels in all tissues examined after 24h were at least 100,000-fold less than known toxic levels.

Toxicokinetic of HEMA in guinea pigs

OBJECTIVE

Unconverted 2-hydroxyethylmethacrylate (HEMA) can be released from dental resin materials and can enter the body in humans. In the present study the uptake, distribution and excretion of 14C-HEMA applied via different routes were examined in vivo in guinea pigs.

METHODS

HEMA (0.02 mmol/kg bw labelled with a tracer dose 14C-HEMA 0.3 Bq/g bw) was administered by gastric tube or by subcutaneous injection. Urine, feces, and exhaled carbon dioxide were collected for 24 h after administration. Guinea pigs were killed 24 h after the beginning of the experiment and various organs removed and 14C radioactivity measured.

RESULTS

Low fecal 14C levels (about 2% of the dose) and urinary levels of about 15% after 24 h were noted with either route of administration. Direct measurement of exhaled CO(2) showed that about 70% of the dose left the body via the lungs. Two pathways for the metabolism of 14C-HEMA can be described. It is likely that 14C-pyruvate is formed in vivo resulting in the formation of toxic 14C-HEMA intermediates. 14C-HEMA was taken up rapidly from the stomach and small intestine after gastric administration and was widely distributed in the body following administration by each of the routes.

CONCLUSIONS

Clearance from most tissues following gastric and intradermal administration was essentially complete within one day. The peak HEMA levels in all tissues examined after 24 h were at least onemillion-fold less than known toxic levels.

Allergic contact stomatitis caused by acrylic monomer in a denture

A 71-year-old edentulous man developed a severely painful red mouth at sites of contact with a new denture. Patch testing showed allergy to samples of the denture material and to 2-hydroxyethyl methacrylate. Patch testing to methyl methacrylate was negative. Prolonged boiling of the denture resulted in reversal of his symptoms and samples of this fully cured denture material produced negative patch tests. While allergy to acrylates is a rare cause of stomatitis, this possibility must be considered in patients presenting with oral symptoms. Material safety data sheets are unreliable in providing information regarding the type of acrylate present in the material. Hence, patch testing should be performed with a battery of acrylate allergens as well as with small samples of the denture material.