Investigation of reactions to dental materials

Patients undergoing dental treatment can be exposed to a wide range of potential allergens, but adverse events seem infrequent. Patients with symptoms or signs of stomatitis, burning, tingling, cheilitis, oral lichenoid lesions, lip and facial swelling may relate their problems to dental treatment or to the use of dental products. Investigation for immediate type or delayed type hypersensitivity is indicated using patch testing, prick testing and blood tests for allergen-specific IgE. The main allergic reactions found in patients include contact allergy to metals, cosmetics, food additives, flavours and acrylates, and immediate type allergy to latex. Adverse reactions following the administration of local anaesthetics are seen in about 0.5% of cases, but immediate type allergy to these agents is rare. In dental staff, occupationally related problems are common and usually take the form of hand or facial dermatitis or respiratory disease. The most common allergic reactions in dental staff are immediate type allergy to latex, and contact allergy to rubber additives, fragrances, acrylates and formaldehyde. Occupational irritant problems causing hand dermatitis are probably more common in dental personnel than is dermatitis caused by contact allergy. Patch testing and tests for immediate type allergy are useful investigative methods in the investigation of patients who present with oral or facial symptoms possibly related to dental treatments and are also beneficial in dental personnel who present with hand or facial dermatitis or respiratory symptoms.     

Positive patch test reactions to allergens of the dental series and the relation to the clinical presentations

The clinical manifestations of contact allergic dermatitis to dental materials are not uniform. This study was performed to detect the frequent allergens in the dental series associated with contact dermatitis and to define the causal relationship between the different allergens and the relevant clinical presentations. Between the years 2000 and 2004, 134 patients, aged 20-80 years, were patch tested. 121 patients were included in the study. The most frequent oral manifestations were cheilitis and perioral dermatitis (25.6%), burning mouth (15.7%), lichenoid reaction (14.0%), and orofacial granulomatosis (10.7%). 18 (14.9%) patients were dental personnel, all of whom suffered from hand dermatitis. The common allergens detected included goldsodiumthiosulphate (14.0%), nickel sulfate (13.2%), mercury (9.9%), palladium chloride (7.4%), cobalt chloride (5.0%), and 2-hydroxyethyl methacrylate (5.8%). Positive reactions to metals were frequent in all the different clinical variants, and no specific association between a specific clinical presentation and a particular allergen was found. Allergy to mercury was not a significant factor contributing to the pathogenesis of oral lichenoid reactions. However, a strong association with contact allergy to mercury in dental fillings was found in 2 patients with orofacial granulomatosis.     

A multicenter study of patch test reactions with dental screening series.

Background: Dental products contain many allergens, and may cause problems both for patients undergoing dental treatment and for dental personnel because of occupational exposure. Individual patch test clinics may not study sufficient numbers of patients to collect reliable data on uncommon allergens. Objective: To collect information on dental allergens based on a multicenter study. Materials and Methods: The Finnish Contact Dermatitis Group tested more than 4,000 patients (for most allergens, 2,300 to 2,600 patients) with dental screening series. Conventional patch testing was performed. The total number and percentage of irritant (scored as irritant [IR] or doubtful [?]) and allergic (scored as +, ++, or +++) patch test reactions, respectively, were calculated, as well as the highest and lowest percentage of allergic patch test reactions recorded by the different patch test clinics. A reaction index (RI) was calculated, giving information on the irritancy of the patch test substances. Results: The most frequent allergic patch test reactions were caused by nickel (14.6%), ammoniated mercury (13%), mercury (10.3%), gold (7.7%), benzoic acid (4.3%), palladium (4.2%) and cobalt (4.1%). 2-hydroxyethyl methacrylate (2.8%) provoked most of the reactions caused by (meth)acrylates. Menthol, peppermint oil, ammonium tetrachloroplatinate, and amalgam alloying metals provoked no (neither allergic nor irritant) patch test reactions. Conclusion: Patch testing with allergens in the dental screening series, including (meth)acrylates and mercury, needs to be performed to detect contact allergy to dental products.     

Studies on contact dermatitis in stomatological staff

84 patients with contact dermatitis (38 dentists, 18 dental nurses and 28 dental technicians) were studied. All were patch tested with standard patch test series of the CMEA countries and with some professional allergens. 31 (36.9%) of them had allergic occupational contact dermatitis and 39 (46.2%) had irrtiant contact dermatitis. The highest prevalence of irritant contact dermatitis was found among dental surgeons. The percentage of atopics in the group of patients with irritant contact dermatitis was twice greater compared to that in the group of patients with allergic contact dermatitis. The contact allergens most frequently encountered were acrylic compounds, disinfectants (eugenol, thymol, trioxymethylene) mercury compunds and anesthetics.     

Contact dermatitis to metals

Metals are in close contact with skin and mucous membranes on a repeated, if not constant, basis. Nickel and mercury, well-recognized causes of contact dermatitis; gold and palladium, recently gaining acceptance as patch test allergens on standard screening trays; and cobalt are reviewed in this article. Sensitization to nickel, the most frequently identified allergen on patch testing, is associated with ear piercing. Contact with this potential allergen is ubiquitous. Mercury may be encountered as organic mercury in thimerosal, used as an antiseptic and a preservative in topical medications and vaccines, and metallic mercury found in dental amalgam and thermometers. Both forms may cause contact dermatitis. Gold, recognized as a frequent sensitizer, has been implicated in some cases of eyelid, patchy diffuse and oral lichenoid dermatitis. Cobalt allergy, found frequently in patients who are nickel allergic, also has been associated with ear piercing. Palladium sensitivity is often associated with nickel allergy. However, the incidence of clinical relevance is yet to be established.     

Contact allergy to dental materials

The oral mucosa is constantly exposed to a large number of potentially irritating and sensitizing dental materials. Dental materials used for fillings and fixed or removable replacements must have a good biocompatibility. Metals including palladium are used in alloys for the production of the core of crowns, onto which porcelain is bonded for the generation of an artificial tooth to which the patient can develop an allergic contact dermatitis. The clinical manifestations of contact allergy to dental materials are not uniform. Objective symptoms of a contact allergy include a stomatitis and lichenoid reactions. However, patients may present with more subjective affections of the oral mucosa including burning, pain and dryness which need to be differentiated from a real contact allergic reaction. In this article we focus on the management of contact allergy to dental materials.     

Kontaktallergie auf Dentalmaterialien

The oral mucosa is constantly exposed to a large number of potentially irritating and sensitizing dental materials. Dental materials used for fillings and fixed or removable replacements must have a good biocompatibility. Metals including palladium are used in alloys for the production of the core of crowns, onto which porcelain is bonded for the generation of an artificial tooth to which the patient can develop an allergic contact dermatitis. The clinical manifestations of contact allergy to dental materials are not uniform. Objective symptoms of a contact allergy include a stomatitis and lichenoid reactions. However, patients may present with more subjective affections of the oral mucosa including burning, pain and dryness which need to be differentiated from a real contact allergic reaction. In this article we focus on the management of contact allergy to dental materials.     

The CXCR3 activating chemokines IP-10, Mig, and IP-9 are expressed in allergic but not in irritant patch test reactions.

Differentiation between allergic and irritant contact dermatitis reactions is difficult, as both inflammatory diseases are clinically, histologically, and immunohistologically very similar. Previous studies in mice revealed that the chemokine IP-10 is exclusively expressed in allergic contact dermatitis reactions. In the present study, we investigated whether the mRNA expression of IP-10 and the related CXCR3 activating chemokines, Mig and IP-9 are also differentially expressed in human allergic contact dermatitis and irritant contact dermatitis reactions. Skin biopsies from allergic (13 cases) and sodium lauryl sulfate-induced irritant patch test reactions (13 cases), obtained 1-72 h after patch testing, were studied by means of an in situ hybridization technique. Results of chemokine mRNA expression were correlated with clinical scoring, histology, and immunohistochemical data including the proportion of inflammatory cells expressing CXCR3, the receptor for IP-10, Mig, and IP-9, and ICAM-1 and HLA-DR expression on keratinocytes. IP-10, Mig, and IP-9 mRNA were detected in seven of nine allergic contact dermatitis reactions after 24-72 h, but not in sodium lauryl sulfate-induced irritant contact dermatitis reactions. ICAM-1 expression by keratinocytes was only found in allergic contact dermatitis reactions and correlated with chemokine expression. Moreover, up to 50% of the infiltrating cells in allergic contact dermatitis expressed CXCR3, in contrast to only 20% in irritant contact dermatitis reactions. In conclusion, we have demonstrated differences in chemokine expression between allergic contact dermatitis and irritant contact dermatitis reactions, which might reflect different regulatory mechanisms operating in these diseases and may be an important clue for differentiation between allergic contact dermatitis and irritant contact dermatitis reactions.     

Oral lichenoid lesions (OLL) and mercury in amalgam fillings

84 patients with oral lichenoid lesions (OLL) were seen in the contact dermatitis clinic. All these patients had reticulate, lacy, plaque-like or erosive lichenoid changes adjacent to amalgam fillings. Patch testing to metallic mercury, 0.1% thimerosal, 1% ammoniated mercury, 0.1% mercuric chloride, and in some cases 0.05% phenylmercuric nitrate and amalgam discs was undertaken. 33 (39%) patients had positive patch test findings. 30/33 patch test positive patients had replacement of their amalgam fillings, with 28 (87%) patients experiencing improvement of symptoms and signs within 3 months. This confirms that mercury allergy is a factor in the pathogenesis of OLL in some cases. In cases where patch test negative patients improve with amalgam replacement, mercury may be acting as an irritant in the pathogenesis of OLL.     

Schleimhauterkrankungen aus allergologischer Sicht

The oral allergy syndrome is one of the most common form of food allergy and manifests as contact urticaria of the oral mucosa after consumption of cross reacting foods. Whereas allergic contact stomatitis often occurs due to dental materials, allergic contact cheilitis is usually a reaction due to topical therapeutics like herpes ointments or lip care products. As late type reactions are more frequent than immediate type reactions in the anogenital mucosa, contact dermatitis in this area should be identified via epicutaneous testing. In case of contact urticaria at the genital mucosa, a semen allergy or a latex allergy should be given due consideration as a possible cause. Angioedemas, which are mostly common histamine mediated, usually prefer skin areas with loose connective tissue such as the oral or genital mucosa. Fixed drug eruption also occurs preferentially in these areas. Bullous drug-induced skin reactions (e.g., SJS and TEN) are characterized by severe hemorrhagic, erosive affections of mucous membranes.     

Contact dermatitis from pyrrolnitrin

A further series of 42 cases of contact dermatitis from an antimycotic agent, pyrrolnitrin, are reported. Patch testing produced positive allergic reactions in 41 cases and an irritant reaction in I case. The allergic contact dermatitis was generally associated with a characteristic widespread secondary eruption resembling erythema multiforme.     

Results of evaluating health care workers with prick and patch testing.

BACKGROUND: Health care workers are exposed to many agents that can cause irritant or allergic contact dermatitis. Recently, much attention has been focused on latex sensitivity, which commonly causes contact urticaria. Most studies have examined the conditions of irritant or allergic contact dermatitis and contact urticaria independently. Therefore, we have little information about the possible occurrence of these conditions in the context of combined assessment including both prick and patch testing. OBJECTIVE: To determine the prevalence of irritant and allergic contact dermatitis and contact urticaria in a group of health care workers presenting with skin problems. METHODS: Retrospective review of health care workers assessed by both prick and patch testing in an occupational health clinic. RESULTS: The diagnoses included 61% with irritant contact dermatitis, 31% with allergic contact dermatitis, and 27% with contact urticaria to latex. Eleven percent had both allergic contact dermatitis related to thiuram and contact urticaria to latex. Ninety five percent were deemed to be work-related. CONCLUSION: Health care workers presenting with skin complaints should be assessed with both prick and patch testing.     

Eyelid dermatitis: experience in 203 cases

Allergic contact dermatitis has been considered the most common of the many dermatologic conditions found with eyelid dermatitis. This is a retrospective study of 203 patients who presented with persistent or recurrent eyelid dermatitis with or without dermatitis elsewhere. Almost all underwent patch testing and, when indicated, radioallergosorbent test, skin prick and intradermal tests, and in many cases, usage tests as part of the workup. Relevant allergic contact dermatitis was found in 151 of 203 patients (74.%): 46 (23.%) had protein contact dermatitis, but only 7% had protein contact dermatitis without concurrent allergic contact dermatitis. Less than 1% had irritant dermatitis alone. Twenty-three patients had atopic eczema, of whom 16 also had allergic contact dermatitis, protein contact dermatitis, or both. Other conditions included seborrheic dermatitis (n = 11), psoriasis (n = 7), dry eyes (n = 9), and dermatomyositis or overlapping connective tissue disease (n = 7). Important sources of contact sensitivity include cosmetics, metals, topical medications including corticosteroids, eye medications, dust mites, animal dander, and artificial nails; only 5 cases were caused by nail lacquer. Eyelid dermatitis is a multifaceted clinical problem, but in this group of patients, allergic contact dermatitis was a common cause, even among those with atopic eczema.     

Contact dermatitis in Korean dental technicians

The high risk of occupational contact dermatitis in dental personnel are well accepted throughout the world. There are few reports concerning occupational skin disease in dental personnel in Korea. The purposes of this study were to investigate the frequency, characteristics and causative factors of contact dermatitis in Korean dental technicians. Recording of personal history, physical examination and patch tests with the Korean standard series and dental screening series were performed in 49 dental technicians. Most of the subjects were exposed to a variety of compounds, including acrylics, metals, plaster, alginate, etc. 22 (44.9%) subjects had contact dermatitis, present or past, and the site involved was the hand in all 22. The most common clinical feature of hand dermatitis was itching (77.3%); scaling, fissuring and erythema were other common clinical features. Metals, including potassium dichromate (24.5%), nickel sulfate (18.4%), mercury ammonium chloride (16.3%), cobalt chloride (12.2%) and palladium chloride (10.2%), showed high positive rates in patch test results of 49 dental technicians. 7 positive reactions to the various acrylics were found in 3 subjects. In our study, the frequency and clinical features of the contact dermatitis showed a similarity to other reports, though the patch test results were somewhat different; a higher patch-positive reaction to metals and a relatively lower patch-positive reaction to acrylics than the patch test results reported in Europe.     

Contact orofacial granulomatosis caused by delayed hypersensitivity to gold and mercury

Orofacial granulomatosis, an entity with characteristic clinicopathologic features, is thought to be a reactive process. The authors describe orofacial granulomatosis associated with contact allergy to gold in dental crowns in one patient and a possible allergic contact reaction to mercury from dental fillings in another one. Thus allergic contact dermatitis to the metals gold and mercury should be considered as a possible etiologic agent of orofacial granulomatosis.     

Atypical and unusual clinical manifestations of contact dermatitis to clothing (textile contact dermatitis): case presentation and review of the literature

Although the exact incidence of textile contact dermatitis is unknown, recent studies demonstrate that contact dermatitis produced by allergic or irritant reactions to clothing not only is more frequent than previously thought but also increasing. The clinical features of contact dermatitis (CD) caused by clothing may resemble common allergic contact dermatitis or may have atypical presentations. We report on several cases of clothing-induced contact dermatitis with atypical clinical presentations.     

Allergic and irritant contact dermatitis to calcipotriol.

Calcipotriol (Daivonex R; Leo Pharmaceuticals, Zurich, Switzerland) may cause irritation of the skin, whereas allergic reactions are less common. In the present study we describe two patients with different types of reaction patterns, one presenting as an allergic, the other as an irritant contact dermatitis. Irritative skin reactions were observed only at higher testings doses, in contrast to the allergic type of reaction, which occurred at a lower testing dose. The present observation suggests, that a batch of different testing doses, including lower testing doses may help to differentiate between an allergic type of contact dermatitis and an irritant type of reaction after treatment with calcipotriol.     

Occupational dermatitis in dental personnel: contact dermatitis with special reference to (meth)acrylates in 174 patients

Between 1995 and 1998, 174 dental personnel were referred as patients to the Department of Occupational and Environmental Dermatology, Stockholm. After clinical examination, 131 were patch tested with the Swedish standard series and 109 with a dental screening series. Furthermore, 137 were tested for IgE-mediated allergy to natural rubber latex (NRL). Hand eczema was diagnosed in 109/174 (63%), 73 (67%) being classified as irritant contact dermatitis and 36 (33%) as allergic. Further diagnoses included other eczemas, urticaria, rosacea, psoriasis, tinea pedis, bullous pemphigoid or no skin disease. 77/131 (59%) had positive reactions to substances in the standard series and 44/109 (40%) to substances exclusive to the dental series. 24/109 (22%) patients had positive reactions to (meth)acrylates, the majority with reactions to several test preparations. Reactions to HEMA (2-hydroxyethyl methacrylate), EGDMA (ethyleneglycol dimethacrylate) and MMA (methyl methacrylate) were most frequent. 9 of the 24 were positive only to (meth)acrylates, the remaining 15 also had reactions to allergens in the standard series. 23 of these had hand eczema and 1 facial eczema. In 17 of the 24 allergic to (meth)acrylates, the dermatitis had started in 1995 or later, in 15 within the previous 12 months. Of 8 who had been sick-listed, 7 also had a history of atopy and 6 were allergic to nickel. The most frequent allergens besides (meth)acrylates were nickel, cobalt, palladium, fragrance mix, colophonium and thiuram mix. Allergy to natural rubber latex was diagnosed in 14/137 (10%). In conclusion, irritant hand dermatitis was the dominant diagnosis. Contact allergy to (meth)acrylate was seen in 22% of the patch tested patients, with reactions to 3 predominant test substances. 1/3 of the patients with allergy to (meth)acrylates had been sick-listed for dermatitis, but in all these cases the (meth)acrylate allergy was seen together with atopy and/or further contact allergies.     

Contact dermatitis from beryllium in dental alloys

An increasing number of metals with the potential to cause allergic contact dermatitis have found their way into dental alloys for economic and practical reasons. 2 patients are reported who developed gingivitis adjacent to the Rexillium III alloy in their dental prostheses. Patch testing demonstrated positive reactions to beryllium sulfate, a component of the alloy. Components of dental alloys and the mechanism of the contact dermatitis are discussed.     

Case of allergic contact dermatitis due to 1,3‐butylene glycol

1,3‐Butylene glycol (1,3‐BG) is widely used in cosmetics, including low‐irritant skin care products and topical medicaments, as an excellent and low‐irritation humectant. We report a case of allergic contact dermatitis caused by 1,3‐BG. A 28‐year‐old woman suffered from an itchy erythematous eruption on her face. By 2 days of closed patch testing, her own cosmetics and many of the hypo‐irritant skin care products showed positive results. A second patch testing showed positive reaction to 1,3‐BG (1% and 5%). 1,3‐BG was a common component in most of the products that had elicited a positive reaction in the first patch testing. Although allergic contact dermatitis due to 1,3‐BG is not so common, we have to consider 1,3‐BG as a possible contact allergen in the patients presenting with allergic contact dermatitis due to various cosmetics.