Who claims that? In the US, Proposition 65, the Safe Drinking Water and Toxic Act of 1986. Starting the mid-1990, dentistry fell under the purview of the related enforcement activity. In California alone, 80 dental offices were served with 60-day notices for failing to post Proposition 65 warnings, and the California Dental Association has been inundated with inquiries about what the dental offices should do to abide to the requirements¹.
___.The dentist should use in patients’ mouths only products containing ingredients that are considered safe, i.e. only those listed as safe for food contact in Title 21 of the Code of Federal Regulations (21 CFR) promulgated by the U.S. Food and Drug Administration (FDA). Compounds for medical devices involving bodily contact must also be biocompatible to prevent adverse bodily reactions. Typically, this means exhibiting no cytotoxicity in cell culture tests or conformance to the protocols of U.S. Pharmacopoeia (USP) Class VI. In addition, the following tests are required: Ames for mutagenicity, carcinogenicity, mucus membrane irritation (hamster’s pouch), and sensitization on Guinea Pigs.
___.Indeed, the FDA’ classification (Dental Cements and Dental Composites, ADA/ANSI #66, ISO 7489) indicates that while these devices deserve a moderate control, they should not, either directly or through the release of their material constituents: (1) produce significant adverse local or systemic effects; (2) be carcinogenic; or (3) produce adverse reproductive and developmental effects. Therefore, evaluation of any new device intended for human use requires data from systematic testing to ensure that the benefits provided by the final product will exceed any potential risks produced by dental cement materials.
___.In Europe, users should comply with the ISO Standards, which also comprisethree categories. In these standards, most adhesives belong to Class IIa, and the polymers destined for implants to Class IIb (same as cardiac monitors!). The standard ISO-10993, Part 1, uses an approach to test selection that is very similar to the Tripartite Guidance used in the past by the FDA. It also uses a tabular format (matrix) for laying out the test requirements based on the various factors discussed above. The matrix consists of two tables, Initial Evaluation Tests for Consideration” and “Supplementary Evaluation Tests for Consideration”. To harmonize biological response testing with the requirements of other countries, the FDA has recognized the ISO standard^2,3.
___.According to Greenpeace, a nongovernmental organization that monitors the environment for the potential damage to human health, plastics are harmful both directly and indirectly, i.e. environmentally. In addition to the chemicals already proven as harmful, by 1981 out of some 100,000 chemicals registered in the European Inventory of Existing Commercial Chemical Substances (EINECS), 75 % are little known from the point of view of their toxicity⁴. Every year, variations of these products, or new ones that may contain insufficiently studied chemicals, are launched. Quite often, these form the subject of controversies between the manufacturers’ lobbies, toxicologists and environmentalists, the governments often playing only as referees.
Polymer toxicity. According to Greenpeace, plastics can be ranked according to their hazardous characteristics, Fig. 1. Polyvinyl chloride, considered the most harmful plastic, is at the top, and the bio-based plastics, the least dangerous, at its base. This classification, based upon human exposure and the impact on the environment, can serve as a crude ranking criterion.
___.Opening Dentaurum’s last catalogues5, is easy to see that all of these plastics are listed as currently used in their orthodontic products. In what follows, we will discuss the dangers some of these pose to health using Greenpeace’s classification.
Vinyls. The most dreaded plastic, polyvinyl chloride polymers, or short PVC or vinyls, registers a global demand for medical uses of 1.2 billion lbs. The polymer per se is less dangerous than many, but it is associated with controversial plasticizers. As the latter may outweigh the polymer, this combination will be discussed latter.
Polyurethanes. Oligomers (low molecular weight polymers), unreacted monomers and excesses of harmful additives may render polyurethanes dangerous6. During use, polyurethanes may degrade, a process that may have started even from their manufacture, since temperatures of 150-200oC are commonly used for their injection molding or extrusion. This interval is close to that of the decomposition of isocyanates. Traces of 4,4’ diamino diphenyl methane (a toxic product resulting from the decomposition of the widely used MDI or 4,4’ methylene diphenyl diisocyanate) have been found in both Pellethane 2363™ (Dow Chemical Co) and Biomer™. Ethicon withdrew the latter in the late 1980’s from fear of liabilities. Both elastomers were designed for medical use⁷, i.e. to withstand the oral environment and the presence of enzymes (pepsin, papainase, chymotripsin, esterase) and microbes, especially fungi.
___.Polyurethane elastomers are subjected to hydrolysis that leads to a drastic depolymerization, the least stable being the polyether-polyurethanes^7,8. Another mechanism that leads to polyurethane decay and cracking is the proximity to metals, the corrosion of which could generate a metal ion-induced oxidation. Attempts to prevent this complex interaction metal-polyurethane-body have focused on using noncorrosive metals, or coating the metal, as well as incorporating antioxidants8. Polyurethane elastomers have been proven to be cytotoxic by at least one study⁹.
___.The toxicity of acrylic and methacrylic derivatives of polyurethanes, used sometimes as alternatives to Bis GMA polymers (see below), are less studied and exhibit a higher leaching¹⁰. Their aliphatic structure should, however, place them in the less controlled polyesters category, as shown by their comparative testing in suppressing macrophage activity¹¹.
Polycarbonates. Although polycarbonates are polyesters and theoretically derivefrom the inoffensive carbonic acid, these are considered more potentially harmful. The reason is that these are also derivatives of Bisphenol A (BPA) into which these are converted during hydrolysis. In the same category should also be classified other polyesters which release BPA such as bisphenol A dimethacrylate (BAD) and bisphenol A diglycidyl dimethacrylate (Bis GMA), etc. However, in order to respect Greenpeace’s classification, the latter will be discussed under Polyesters.
___.Chemically known as 4,4’-isopropylidenediphenol, BPA is currently used in the manufacture of resins and fungicides. Known for over 70 years as an oestrogenic^12-14, its derivatives’ use in health-related fields is controversial. The allegations are that it generates premature puberty among young girls (and possibly cancer), and influences men’s fertility due to its structural analogy with oestrogens. True or not, Japan’s Environment Agency does not accept polycarbonate bottles citing fears of bisphenol A contamination and many baby bottle processors have switched from polycarbonates to polyether-sulfones.
Aliphatic polyesters. Aliphatic polyacrylates and methacrylates, and PMMA in particular, have a relative low toxicity when compared with the aromatic ones, and especially with those releasing BPA. While the amount of methyl methacrylate released by a PMMA composite denture plate has been determined to be as high as 0.18% from the polymer, its presumable effect is to act as only as an allergen¹⁵. Among the less viscous resins that are added to Bis GMA to render it more fluid, TEDGMA leaks the most¹⁶.
___.The polymers of triethyleneglycol dimethacrylate (TEGDMA) and 2-hydroxy-ethyl methacrylate (HEMA) have shown to be more toxic to lung cells than some mercury compounds¹⁷. Extracts from some composites containing high amounts of TEGDMA and HEMA were found to be extremely cytotoxic¹⁸, generating adverse systemic effects on patients. Both monomers are known to produce allergies in dental nurses and dentists¹⁹.
___.Being water soluble, HEMA may cause more troubles than the other monomers. Thus, it perturbs the human dental pulp cycle²⁰, it suppresses the mitochondrial activity of macrophages and it can generate inflammatory reactions with the connective tissues²¹.
Aromatic polyesters. The derivatives of BPA (see above) are discussed in this less controlled category to respect Greenpeace’s classification and because the amount of basic monomer (e.g. Bis GMA) is relatively small (high cross-linking, low solubility)¹⁰. According to the Dental Investigation Service of the US Air Force²², all the following products contain Bis GMA: Aelite Flo™ (Bisco Dental); Fl Restore™ (Den-Mat); Flow it™ (Jenneric-Pentron); Revolution™ (E &D Dental); Ultraseal XT Plus™ (Ultradent); Star Flow™ (Danville Eng.); Versa Flo™ (Centrix); Terric Flow™ (Ivoclar). Since few other flowable resins are used to make dental products, there is a high probability that most of these contain Bis GMA.
___.The aromatic components in the early resins were found to be mutagenic^23,24. Up to 14% of the total mass of the direct-bonding adhesive can leach out, and the discharge may continue up to two years^25,26. In addition, the monomers and oligomers released by the resins were found to be cytotoxic^27,28. It is reasonable to deduce that the leaching decreases in the following order, proportional with the content of inert filler: sealants> liquid-solid>liquid-paste> paste-paste systems. The cured adhesive is significantly less toxic, as it may have up to 80% inert filler. Completely polymerized resins were also described to be insoluble²⁹.
___.Polyesters containing benzenic cycles are controlled as much as the polycarbonates, as these include some of the most used polyacrylates and the polymethacrylates. Tests comparing several heat, cold and light-cured acrylic materials under the ISO-standard 10993-5 has shown that all of these were cytotoxic: only the prosthetic acrylic (heat-cured!) could be graded “non-toxic”³⁰. While the cytotoxicity response of acrylic-based restorative materials cured chemically and with light may not be the same in time periods, after a 24h exposure it equalizes³¹. The higher cytotoxicity exhibited by the oxygen-inhibited layer that forms above the polymer clearly demonstrates a major contribution of the unpolymerized monomers and the related oligomers.
___.In animals, a study performed on a classic estrogen target tissue, rat vaginae showed a response in some of the animals tested³². Further studies confirmed that Bis GMA is weakly estrogenic in mice³³ and that BPA influences the growth of the rats mammary gland³⁴. Answering criticisms, a Spanish team supported in vitro the results previously obtained in vivo³⁵, while trying to determine the relationship of the structure of the BPA to oestrogenicity^36,37.
___.The controversy is far from over. While some studies have concluded that dental resins in general do not represent a significant source of BPA or BAD exposure³⁸, or that even if a weak oestrogenic effect is not impossible, the effects are small and the risk assumable³⁹, the clinician should not drop his guards, as newer studies are likely to dispute these findings. Their potential harm seems to have far reaching effects. Thus, while the layer of low molecular weight polymers (oligomers), known as the oxygen-inhibited layer is considered the most cytotoxic⁴⁰, this effect was found to be significant, even two years after the initial palso olymerization²⁷. No mix-materials, as well as sealants, exhibit greater toxicity both initially after mixing and after 30 days post-polymerization²⁸.
Glass ionomers. Phosphate cements have been found to be less cytotoxic than the carboxylate cements that contain polyacrylic acid⁴¹. The cytotoxic effect of resin-modified glass ionomer cements, which contain two types of acrylates (Bis GMA and TEGDMA) in the resin, hydrophobic part, and an oligomers of acrylic acid in aqueous one) has been attributed not only to the unpolymerized monomers, but also to the heavy metals contained in the glass⁴². As newer formulations are used, findings about the toxicity of their ingredients are expected. Thus, recently 4-META, an aromatic monomer, has started to enter in composite formulation, although till recently it was just an additive⁴³. Not only was it claimed to suppress the mitochondrial activity of macrophages, but also that it leaves a residual effect¹¹.
___.An important health-related issue is the polymers’ extraction in view of removing harmful components. While some researchers claim that the restorative materials’ elution with water for 3 days⁴⁴, or just boiling⁴⁵ shows a significant reduction in toxicity, another study has shown that sufficient components are released to kill or alter cellular functions even after two weeks of exposure in artificial saliva46.
Polyolefins. Polyethylene, and in special Ultra high-molecular-weight polyethylene (UHMWPE), is used in medicine for lining contact surfaces of implants, and in orthodontics as fibers in splints or reinforcements. To improve its resistance, a high degree of cross-linking is generated using a bombardment with high-energy electron beams, followed by annealing below its 137^oC melting point. The last operation is currently used to destroy the free radicals formed during irradiation: left as such, these react with oxygen and form intermediates that cause the polymer chain to break.⁴⁷
Additive toxicity.
___.Plastics are often condemned not due to the polymers, but to the additives they contain. Indeed, when referring to the various plastics, only the polymers are usually mentioned and little information is given to the chemistries and the additives that enable these products to be as useful as they are. Additives comprise plasticizers, impact modifiers, heat stabilizers, lubricants, biocides, antioxidants, antiblocking agents, slip agents, light stabilizers, clarifying agents, organic initiators, blowing and coupling agents.
___.While additives are more toxic that the polymers to which these are added, the amount used in orthodontics is significantly smaller. Many leach into the human body: even the fillers may leach from cross-linked composites⁴⁸. Immersed in water or synthetic saliva, composites leach, along with monomers, additives such as ultraviolet stabilizers (TINUVIN P), plasticizers (dicyclohexyl phthalate and bis (2-ethylhexyl) phthalate), initiators (triphenyl stibine), coupling agents (gamma-methacryloxypropyl trimethoxy-silane), and phenyl benzoate³⁴. In the case of vinyls, plasticizers can often reach over half of the total weight. Without them, PVC is hard and brittle, and so are PMMA plates, dentures and linings. The best and most commonly used plasticizers are the phthalates, aromatic esters suspected to mimic hormones^{10, 49, 50-55}. Dibutyl phthalate was found to be a testicular toxicant in three species of young adult laboratory animals in high dose. Adult female functional reproductive toxicity (decreases in fertility) has been evidenced in rats54. Such substances can affect the hormonal system of an organism in a wide variety of ways, blocking the hormone action and accelerating their breakdown, eventually causing cancer and death.
Conclusions
___.The plastics and the ingredients used in orthodontics are not highly useful, but also toxic in various degrees. The publication in 1996 of the book Our Stolen Future⁵⁶, with a foreword by the then Vice President Al Gore, has stirred emotions and has fueled a campaign against plastics long since advocated by organizations such as Greenpeace, Chemical Impact Project, the World Wildlife Fund, World Resources Institute and Friends of the Earth. Among their successes is the fact that in all the construction related to the 2000 Olympic games in Sydney, no PVC was used.
___.In contrast, the American Plastics Council has shown that intermediate products such BPA and plastic additives such as the phthalates have been used without problems for over 40 years. The use of the latter has received a positive review from the former US Surgeon General Dr. C. Everett Koop⁵⁷and the American Council on Science and Health panel who have concluded that “DEHP and DINP (phthalate esters) are not genotoxic” and that the current human exposure levels in products containing them are “not harmful”⁵⁸.
___.While no conclusive effect on orthodontic patients has yet been thoroughly demonstrated, the clinician should be always aware and avoid any excessive exposure to the polymeric products. He should also be able to assess their toxicity, as the number of products currently used exceeds by far the testing possibilities of governmental or professional organizations.
The simple test that follows should allow him to be in control.
References
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36. Novillo-Fertrell A, Rivas A, Pazos P, Pedraza V Navajas JM, Olea N, Determination of bisphenol A and related aromatic compounds released from Bis-GMA-based composites and sealants by high performance liquid chromatography, Environ Health Perspect 2000; 108(1) (Online)
37. Pulgar R, Olea-Serrano MF, Novollo-Fertrel A, Rivas A, Pazos P, Pedraza V, Navajas JM, Olea N, Determination of bisphenol A and related aromatic compounds released from Bis GMA-based composites and sealants by high performance liquid chromatography, Environmental Health Perspectives 2000; 108(1): 21-7).
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52. Kavlock RJ, Daston GP, DeRosa C, Fenner-Crisp P, Gray LE, Kaattari S, Lucier, G, Luster M, Mac M J, Maczka C, Miller R, Moore J, Rolland R, Scott G, Sheehan DM, Sinks T, Tilson HA, Research needs for the risk assessment of health and environmental effects of endocrine disruptors: A report of the U.S. EPA-sponsored workshop. Environ. Health Persp. 1996: 104, Suppl. 4: 714-740
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58. FDA, 21CFR177: 333-338

A-DO-IT-YOURSELF DETECTION OF LEACHING POLYMERS

___.All polymers leach: the difference is the degree and nature of the leachate. The cross-linked and high molecular weight ones not only leach less, but also retain better in their tangled network the oligomers, the additives and even the monomers. While polymers like the vinyls exude these even when dry, others do so when in contact with liquids.
___.All the studies showing what can be extracted by water quoted in the previous article refer to specific compounds and use sophisticated analyses. What follows is simple and general, starting from the idea that the less leachate, the better. While it is true that not all polymer ingredients respond the same way, some reacting faster than the others, the method allows to chose the formulations which leach less.
From hosiery to dentistry. To get resistant stockings, it is necessary to test for impurities caprolactam, the monomer for nylon 6. Subjected to a solution containing potassium permanganate (MnO₄K), the organic compounds are oxidized while the dark purple-colored manganese, valence VII, turns into the nearly colorless manganese II. In industry, the correct colorimetric test uses expensive spectrometers endowed with selectors for continuous variations of wavelength¹. A variation of the method is accurate enough to determine organic impurities in water², the difference being that chemical analysis is used instead.
___.For faster results, however, the synthetic fibers industry uses a simplified test based upon the difference in the resistance to oxidation exhibited by caprolactam and its impurities. The more the latter, the shorter the time till the mixture of caprolactam and MnO₄K discolors. Applied and adapted to some products used in orthodontics, the method allows to pick the least leaching ones.
Materials and method
___.To 1 liter distilled water were added 1.6 g MnO₄K ACS reagent grade, 99+% (0.001m solution): after stirring, the solution was left for at least an hour before use. In parallel, several polymeric products were spread thinly on a teflon surface and cured following their manufacturers recommendations by mixing the parts or using blue light. After leaving them overnight, the foils were broken into pieces and 0.1g of each was inserted into 25 ml capped and marked test tubes containing the permanganate solution as shown in Fig. 1. Photographs were taken in time and compared, as shown in Fig. 2 and 3.
Experiment I. The following products were tested, each marked as follows: 1. Fuji Ortho LC, compomer, GC America, Chicago, IL 60658 ; 2: PQT, adhesive, Ultradent, S. Jordan, UT 84095; 3. Perma Quick, adhesive, Ultradent; 4: Light Bond sealant, Reliance; Itasca, IL 60143; 5: LCR, adhesive, Reliance; 6: Light Bond, adhesive, Reliance; 7: Quick Cure, adhesive, Reliance; 8: Band Lock, adhesive, Reliance; 9: Bond Fast, adhesive, Reliance; 10. Phase II, adhesive, Reliance; 11: Maximum Cure, sealant, Reliance; 12: Advantage, adhesive, Ortho-Organizers, San Marcos, CA 92069; 13: Jet, self curing resin, Lang Dental, Wheeling, IL 60090; 14: Ketac-Cem, glass ionomer, ESPE, Seefeld, Germany; 15: Maxibond, adhesive, Ortho-Source, N. Hollywood, CA 91617; 16: Genie, Lee Pharmaceuticals, S. El Monte CA 91733. After 24 hours, the discoloration of many samples was evident, as shown in Fig 4b.
Experiment II. As only after 24 h, marked differences in color were obtained, the MnO₄K solution was diluted 1:3 with distilled water. The number of samples was smaller and instead three monomers were added. This time, the samples marked from 0-10 were as follows: 1: Control; 2: Genie; 3: Jet ; 4: Light Bond, sealant; 5: Phase II, adhesive; 6: Ethoxylated bisphenol A dimethacrylate monomer, Sartomer; West Chester, PA, 19380; 7: Bis GMA monomer (Rohamere®), Rohm & Haas, Philadelphia, PA 19106-2399; 8. Diethylene glycol dimethacrylate, Sartomer; 9: Methyl methacrylate, Lang Dental, Wheeling, IL 60090; 10: Quick Cure, Reliance.
___.As less MnO₄K was used for the same amount of polymeric product, the color change occurred faster, and in some instances instantaneously, as it is evidenced in Fig. 5 and 6.
Experiment III. According to the ISO “Permanganate index for water”², sulfuric acid has to be added to enhance the reaction. As in experiment II there were no major differences observed between the readings after three and thirty minutes, a new test was performed in which phosphoric acid was added to lower the pH to 1.
___.The samples tested were as follows: 0: Control; 1: Jet; 2: LCR; 3: PQT; 4: Perma Q; 5: Light Bond, adhesive; 6: Ketac-Cem; 7: Max Cure; 8: Ethoxylated bisphenol A dimethacrylate monomer; 9: Bis GMA monomer.
___.This time, the reaction was by far faster, reducing the test time to few minutes. The discoloration of the permanganate solution is shown in Fig. 7-10. As a difference from Experiment I, when a brown-black precipitate was formed, see Fig. 4b, in this case the samples were obtained clean and the solution became clear, Fig. 4a.
Experiment IV. Based upon the above, a do-it-yourself test can be put together. Aside from potassium permanganate, a common disinfectant, all the devices and ingredients are common and easy to use in an office. Instead of weighing, a solution of permanganate of appropriate concentration was made by adding tap water to the powder till the text of newspaper could be read through an inch of solution held in a glass cup with flat bottom. To a pint, few drops of muriatic acid (as used for pools) were added. A tablespoon of this solution was poured on the polymer samples placed in a eramic egg holder.
___.Some polymers were tested successively in one or several portions, each enough to bond some three teeth (as measured with the little scoop provided by Ketac-Cem.). Fig. 11 -13 show the color change in time of the previously used polymers: 1: Light Bond, adhesive; 2. Light Bond, sealant; 3: Fuji Ortho LC; 4: Quick Cure; 5. PQT; 6: Jet; 7: Ketac-Cem; 8: Two portions of Ketac-Cem; 9: Maximum Cure, sealant; 10. Genie, one portion; 11. Genie, two portions; 12: Genie, three portions.
Results
___.While differing in speed, in all cases oxido-reduction reactions take place, as shown by the discoloration of all samples, excepting the controls. The reaction occurs somewhat differently in neutral and acid environment. Methyl methacrylate is oxidized instantaneously, as a difference from both the bis phenol A-derived monomers. Interestingly, the cold cure Jet, from which unbound methyl methacrylate could presumably easily leach, is less oxidized than the other samples. Fuji’s compomer leaches more reducing ingredients than the others. Next was Genie and the sealants, and last the adhesives. Acids and higher ratios polymer/permanganate solution enhance leaching, as shown by the clear solutions around the samples. The test is completed in less than two hourrs, see Fig. 11
Discussion and conclusions
___.Manganese’s discoloration is the result of a stoichiometric relation between the oxidizing agent and the reducing sample, as shown below for a simpler compound, glycerol:
___.___.4KMnO₄+4C₃H₅(OH)₃=7K₂CO₃+7Mn₂O₃+5CO₂+16H₂O
___.In a neutral environment, the permanganate is reduced to MnO₂,and Mn₂O₃ which precipitate (see Fig. 4b) and gives the liquid a yellow-brown color. In an acid environment, manganese is transformed into a nearly colorless salt (Mn²⁺). If to the yellow-brown acid solution containg manganese oxides more reducing agent (polymer) is added, the color changes to clear as the manganese is further reduced to a salt.
___.All the polymers tested leached, as witnessed by a comparison with the controls. While the ISO-method² is so sensitive that it is currently applied to tap water, the present do-it-yourself method proposed is not. Instead of a spectrophotometer and weighing, it uses visual estimation. Instead of sulfuric acid, it uses common muriatic acid. However, it can provide an approximation of the degree to which a polymer leaches oxidizable, organic matter. While the latter may not always be harmful, as is the acrylic acid released by glassionomers, in most cases it is, as is the case of plasticizers or of hydrolized bis-phenol A. In general, however, the less leaching, the better the cure and the safer the product, as the molecular weight of the polymer is higher.and the crosslinked network denser. In thelatter case, larger molecules become entangled and are kept within the polymer’s structure.
___.By showing the degree of leaching, the method allows the manufacturer to optimize his product, the clinician and the researcher to select the least harmful and the researcher to follow the progress of the leaching in time.
References.
1. Caprolactam for industrial use-Determination of permanganate index, ISO 8660:1988
2. Water quality -Determination of permanganate index, ISO 8467: 1993:

KNOW YOUR TOOLS!

___.An unjustifiable interest in the clinical aspects, to the detriment of the devices used, can hurt both the patient and the clinician. Due to the ever increasing enforcement of the USA’s Proposition 65, the Safe Drinking Water and Toxic Act of 1986, clinicians are now held responsible for what they use. The fact that the device is freely sold on the market cannot justify failures in providing the service the patient and the law expects. In an increasingly sophisticated but litigious world, the clinician has to keep up with his tools. Prof. Dr. Dr. Eng. C. G. Matasa, Ortho-Cycle’s President, has dedicated 30 years to the field: listen to him at the Doctors’ Scientific Lectures while he presents “Do-it-yourself Methods of Testing”, May 5th, 2002 at the 102nd AAO Annual Meeting in Philadelphia, Biomaterials, 3:45-4:30 pm: you’ll learn simple ways to detect faulty or harmful alloys and plastics. Visit his two Scientific Posters, each describing simple, do-it-yourself methods to evaluate and compare either bond strength or slot width tolerance.
Keep in mind not only that Orthodontic Devices are low in the FDA’s priority as control concerns, but also that there are not enough studies to keep up with the flood of new products. Among the latter, some are often better and less expensive than the older ones, a fact that makes them worth investigating.
___.Look for Ortho-Cycle’s web site at www.Orthocycle.com for commercial information, and read there the many Insider’s reports we published along the years.
___.Please visit our booth #242 at the 102nd AAO Annual Meeting (Hall A, next to the Café) and check why are we the only company that recycles orthodontic attachments that has been certified ISO 9002, and recently awarded the CE Mark by NIOM (a division of the reputed Scandinavian Institute for Dental Materials). Ortho-Cycle Co. is since 1991 a manufacturer that assumes all the related obligations that include tests for biocompatibility, sterility, quality control, documentation and traceability, as well as the reporting of adverse events. Important to note is that whereas the non-medical devices only need to be safe and do not have to work, medical devices bearing the CE Mark have to be both “safe and effective”.
A CE Mark certification on Medical Devices is de facto a “Quality Mark” (Ryden L, European Heart J. 1998; 19: 1628-31). AAO’s Past President, Dr. Donald Poulton, has showed it earlier when he stated that “recycled brackets are safe and effective” (AAO Annual Report 1997-1998).