Systemic contact dermatitis from dental crowns

Systemic Contact Dermatitis: The Routes of Allergen Entry

Systemic contact dermatitis (SCD) is a generalized reactivation of type IV hypersensitivity skin diseases in individuals with previous sensitization after a contact allergen is administered systemically. Patients with SCD may consider their dermatitis unpredictable and recalcitrant since the causative allergens are difficult to find. If a patient has a pattern of dermatitis suggestive of SCD but fails to improve with conventional treatment, SCD should be taken into consideration. If doctors are not familiar with the presentations of SCD and the possible routes of allergen sensitization and exposure, the diagnosis of SCD may be delayed. In this work, we summarized all of the routes through which allergens can enter the body and cause SCD, including oral intake, local contact (through skin, inhalation, nasal spray and anal application), implants, and other iatrogenic or invasive routes (intravenous, intramuscular, intraarticular, and intravesicular). This will provide a comprehensive reference for the clinicians to identify the culprit of SCD.

Contact allergies to potential allergens in patients with oral lichen lesions

OBJECTIVE

The aim of the present controlled study was to investigate a possible relationship between contact allergies to potential allergens and oral lichen lesions.

METHODS

Eighty-three patients with oral lichen lesions (OLL) and control groups of age- and gender-matched dermatitis patients (DP, n = 83) and patch-tested dermatitis patients randomly selected from files (PSFF, n = 319) were included in the study. OLL and DP groups were patch-tested epicutaneously and examined intraorally.

RESULTS

The frequencies of contact allergy to mercury and carvone were statistically higher in the OLL group than in the DP group. Surfaces of amalgam and composite restorations were statistically more frequent in the OLL group compared to the DP group. Contact allergy to nickel and colophony, the latter with a statistically significant difference, was more common in the DP group. The numerical difference found for nickel allergy was, however, not significant comparing the OLL and PSFF groups.

CONCLUSION

Contact allergy to mercury was overrepresented in patients with OLL and has been reported in previous studies, but the present finding of an overrepresentation of contact allergy to carvone in patients with oral lichen lesions has not been reported previously.

CLINICAL RELEVANCE

Carvone, in addition to mercury and gold, as previously suggested, can be one of the causative or maintenant factors for oral lichen lesions. Carvone-hypersensitive patients with oral lichen lesions should therefore avoid carvone-containing products for oral use.

Systemic contact dermatitis

Systemic contact dermatitis is an inflammatory skin disease that may occur in persons with contact allergy when they are exposed to the hapten orally, transcutaneously, per rectum, intravesically, intravenously, or by inhalation. The most common causes of systemic contact dermatitis are drugs used both topically and systemically. Other causes are ubiquitously occurring haptens, such as the metals nickel, cobalt, gold, and chromate, and aromatic substances such as spices. Avoidance of the offending hapten is the most obvious treatment. For some haptens, such as nickel, diet treatment may be effective. Chelation therapy with disulfiram is another therapeutic option in nickel-allergic patients with systemic contact dermatitis. Hyposensitization therapy has been attempted with some success in systemic contact dermatitis caused by nickel and Parthenium hysterophorus.

Cutaneous and systemic hypersensitivity reactions to metallic implants

Cutaneous reactions to metal implants, orthopedic or otherwise, are well documented in the literature. The first case of a dermatitis reaction over a stainless steel fracture plate was described in 1966. Most skin reactions are eczematous and allergic in nature, although urticarial, bullous, and vasculitic eruptions may occur. Also, more complex immune reactions may develop around the implants, resulting in pain, inflammation, and loosening. Nickel, cobalt, and chromium are the three most common metals that elicit both cutaneous and extracutaneous allergic reactions from chronic internal exposure. However, other metal ions as well as bone cement components can cause such hypersensitivity reactions. To complicate things, patients may also develop delayed-type hypersensitivity reactions to metals (ie, in-stent restenosis, prosthesis loosening, inflammation, pain, or allergic contact dermatitis) following the insertion of intravascular stents, dental implants, cardiac pacemakers, or implanted gynecologic devices. Despite repeated attempts by researchers and clinicians to further understand this difficult area of medicine, the association between metal sensitivity and cutaneous allergic reactions remains to be fully understood. This review provides an update of the current knowledge in this field and should be valuable to health care providers who manage patients with conditions related to this field.

A review of the biologic effects of spine implant debris: Fact from fiction

BACKGROUND

Biologic-reactivity to implant-debris is the primary determinant of long-term clinical performance. The following reviews: 1) the physical aspects of spinal-implant debris and 2) the local and systemic biologic responses to implant debris.

METHODS

Methods included are: 1) gravimetric wear analysis; 2) SEM and LALLS; 3) metal-ion analysis; 4) ELISA, toxicity testing, patch testing; and 5) metal-lymphocyte transformation testing (metal-LTT).

RESULTS

Wear and corrosion of spine-implants produce particles and ions. Particles (0.01-1000 μm) are generally submicron ( <1 µm). Wear rates of metal-on-polymer and metal-on-metal disc arthroplasties are approximately 2-20 and 1 mm(3)/yr, respectively. Metal-on-metal total disc replacement components have significant increases in circulating metal (less than 10-fold that of controls at 4 ppb-Co and 3 ppb-Cr or ng/mL). Debris reactivity is local and systemic. Local inflammation is caused primarily by ingestion of debris by local macrophages, which produce pro-inflammatory cytokines TNFα, IL-1β, IL-6, and PGE2. Systemic responses associated with implant-debris have been limited to hypersensitivity reactions. Elevated amounts of in the liver, spleen, etc of patients with failed TJA have not been associated with remote toxicological or carcinogenic pathology to date. Implant debris are differentially bioreactive. Greater numbers are pro-inflammatory; the smaller-sized debris are more bioreactive by virtue of their greater numbers (dose) for a given amount of implant mass loss (one 100-μm-diameter particle is equivalent in mass to 1 million 1-μm-diameter particles). Elongated particles are pro-inflammatory (ie, aspect ratio of greater than 3). Metal particles are more proinflammatory than polymers, ceteris paribus.

CONCLUSION

Spinal arthroplasty designs have been in use for more than 20 years internationally; therefore, concerns about neuropathology, toxicity, and carcinogenicity are mitigated. Debris-induced inflammation still depends on the individual and the type of debris. The consequence of debris-induced inflammation is continued; vigilance by physicians is recommended monitoring of spinal implants using physical exams and testing of metal content and bioreactivity, as is planning for the likelihood of revision in younger individuals.

Effect of nickel exposure on peripheral tissues: role of oxidative stress in toxicity and possible protection by ascorbic acid

The vast industrial use of nickel has led to environmental pollution by the metal and its by-products during production, recycling, and disposal. Nickel is a known hematotoxic, immunotoxic, hepatotoxic, pulmotoxic, and nephrotoxic agent. Allergic skin reactions are common in individuals who are sensitive to nickel. This article presents a selective review on nickel and its effect on certain metabolically active peripheral tissues of human and animals. The subtopics include nickel sources and uses, exposure pathways, transport, excretion, general health effects, and specific acute and chronic nickel toxicities in peripheral tissues like liver, lungs, and kidneys. The review particularly addresses the nickel-induced generation of reactive oxygen species and increased lipid peroxidation in various metabolically active tissues in humans and animals, and the possible role of vitamin c as a protective antioxidant.

Screening for symptomatic metal sensitivity: a prospective study of 92 patients undergoing total knee arthroplasty

Metal sensitivity (MS) reactions to implant metals represent a rare but well-documented complication following total joint arthroplasty (TJA). Although 20-25% of post-TJA patients develop MS, only a few highly susceptible patients (< 1%) exhibit symptoms. Whether surgeons should perform screening for MS is currently a matter of debate. The present study investigated the clinical importance of screening for patients predisposed to symptomatic MS, and the specific metals causing symptomatic MS following total knee arthroplasty (TKA). Between 2000 and 2002, a total of 108 primary TKAs were performed on 92 patients. Preoperatively, all patients underwent modified lymphocyte stimulation test (mLST) to Ni, Co, Cr, and Fe. Of the 92 patients, 24 (26%) displayed positive preoperative responses to at least one metal. Five patients displayed implant metal-related eczema and were all mLST-positive preoperatively, suggesting that screening for symptomatic MS is clinically useful. Two of these underwent revision TKA and thereafter, eczema healed and mLST results changed from positive to negative. All mLST-positive patients were divided into three groups: Group I, patients with eczema; Group II, patients with clear history of MS; and Group III, patients neither eczema nor history of MS. When the type of sensitive metals were compared among the three groups, a significant association between presence of Cr-sensitivity and development of eczema (P < 0.05) was identified. No significant association was observed between other metals and development of eczema or history of MS. This indicates that Cr is a potential candidate metal for causing eczema in our TKA series, and Cr-sensitivity may offer a potential predictor for symptomatic MS. The present study indicates that the surgeons should undertake routine preoperative screening for MS, particularly to Cr.

An overview of the current status of national reporting systems for adverse reactions to dental materials

OBJECTIVES

Since all dental materials pose a potential risk to patients and members of the dental team, the post-market monitoring of adverse reactions caused by dental materials should be considered essential. This article reviews the current status of post-market monitoring of adverse reactions to dental materials and highlights some of the issues that arise in trying to establish an evidence base on the characteristics of adverse reactions to dental materials.

METHODS

Norway, Sweden and more recently the UK have sought to monitor adverse reactions to dental materials systematically and proactively in an effort to add to the evidence base on the safety of dental materials. Their experiences in undertaking post-market surveillance have been combined in preparing this article.

RESULTS

To date the Norwegian, Swedish and the UK projects has received 1268 reports over 11 years, 848 reports over 5.5 years and 1117 reports over 3 years, respectively, relating to adverse reactions seen or experienced by dental personnel and patients. Presently, there are no harmonized criteria for what can be classified as an adverse reaction related to dental materials. Under reporting is a recognised problem and lack of awareness and lack of clarity as to what constitutes an adverse reaction may be contributory factors. A pro-active reporting system takes a considerable time to become established, but can generate a lot of potentially useful information.

CONCLUSIONS

There is a need to raise the awareness among dental professionals of the potential for adverse reactions due to dental materials and to develop an internationally accepted system of data gathering that can produce the evidence that reflect the extent, severity and incidence of adverse reactions to dental materials.

A triple assay technique for the evaluation of metal-induced, delayed-type hypersensitivity responses in patients with or receiving total joint arthroplasty

The determination of biocompatibility has been dominated historically by the characterization of candidate materials based upon the observation of adverse host responses. However, some adverse responses are subtle in clinical settings and continue to foster debate and investigation. One of these responses is "metal allergy" or hypersensitivity to metallic biomaterials. Current methods used to diagnose hypersensitivity reactions, such as dermal patch testing and migration inhibition assays, are not well accepted in orthopedic practice as a means for the characterization of hypersensitivity to metallic joint-replacement components. An increasing need to resolve whether metal sensitivity may be a significant and/or predisposing factor for eliciting an over-aggressive immune response in patients with metallic implant components requires improved and standardized widespread study. Here we present three in vitro methodologies: (1) a proliferation assay, (2) cytokine analysis using ELISA, and (3) a migration inhibition assay. When in conjunction with one another, these assays may be used to more comprehensively quantify metal-induced hypersensitivity responses. Therefore, these methodologies are detailed with the intent of facilitating multi-center large-scale studies. In the following cases, a multi-assay approach for measuring the prevalence of delayed-type hypersensitivity in orthopedic patients shows the propensity to yield a more comprehensive and, therefore, more conclusive determination than currently employed patch testing or single assay techniques.

Hypersensitivity to metallic biomaterials: a review of leukocyte migration inhibition assays

Metal hypersensitivity is a well-established phenomenon occurring in a variety of domestic and workplace settings. Degradation products of metallic biomaterials may mediate metal hypersensitivity. However, little is known about the short- and long-term pharmacodynamics and bioavailability of circulating metal degradation products in vivo. Mechanisms by which in vivo metal sensitivity reactions occur have not been well characterized and the degree to which metal sensitivity may be a predisposing factor for eliciting an overaggressive immune response remains clinically unpredictable. In vitro leukocyte migration inhibition assays have been used for investigating cell-mediated hypersensitivity reactions to biomaterial and biomaterial degradation products. This review provides a historical and technical summary of four in vitro techniques used for determination of leukocyte migration activity: (1) membrane migration or Boyden chamber, (2) capillary tube, (3) leukocyte migration using agarose technique, and (4) collagen gels. It is difficult to determine which, if any, of these techniques is singularly best suited for the investigation of suspected biomaterial-related symptoms in patients. However, Boyden chamber membrane migration testing is recommended for clinical investigations, principally because a high degree of standardized investigator independent materials and methodologies is necessary for compiling and comparing the results of patients tested at various times over the length of an extended study. Ultimately, in vitro migration inhibition testing has the potential to provide a reliable means for predicting some complications and thus enhancing the outcome for patients receiving metallic implants. Continuing improvements in migration inhibition testing methods, used alone or in combination with other immunologic assays, will likely improve assessment of patients susceptible to biomaterial antigen-induced delayed-type hypersensitivity responses.