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Regulation (EU) 2017/745 of the European Parliament and of the European Council, dated 5 April 2017, in force as of 26 May 2019, has resulted in significant practical consequences that also directly affect the activity of dentists.
We start from the formal assumption that a European Regulation is a binding legal act, directed not only to the Member States, but also to individuals and has a general scope.
It is binding in its entirety and directly applicable in all Member States (Art. 288(2) TFEU).
The Regulation we are dealing with here consists of no less than 123 articles and 17 annexes, and:
“it lays down rules concerning the placing on the market, making available on the market or putting into service of medical devices for human use and accessories for such devices in the Union. This Regulation also applies to clinical investigations of such medical devices and accessories for those conducted in the Union.“
What the practical consequences of the current regulation on implant-retained prostheses are is already clear from the definition of a medical device, i.e. any instrument, apparatus, appliance, software, implant, reagent, material or other article, intended by the manufacturer to be used on humans, alone or in combination, for one or more of the following specific medical purposes:
- diagnosis, prevention, monitoring, prediction, prognosis, treatment or mitigation of disease;
- diagnosis, monitoring, treatment, alleviation or compensation of an injury or disability;
- study, replacement or modification of anatomy or of a physiological or pathological process or state;
- providing information through the in vitro examination of samples taken from the human body, including donated blood and tissues, and which does not exert in or on the human body its principal intended action by pharmacological, immunological or metabolic means, but whose function may be assisted by such means (Chapter 1, Article 2(1)).
In other words, the rule covers any instrument we use to work on our patients and any material we use to make our artefacts. With very few exceptions, all the materials we purchase and use are certified according to the criteria set out in this standard, whether they are mass-produced (dental implants, connecting screws, etc.) or custom-made, such as crowns made by the dental laboratory.
Of the more than 1 million implants used each year in Italy, more than 90% belong to the “two-piece implant systems” group. Two-piece implants”, regardless of the type of connection (internal or external, conical or with clamps, bone level or tissue level) and the type of prosthesis (fixed directly on the implant or interconnected through Multi-Unit Abutments platforms, screwed crown or screwed abutment on which the crown will then be cemented), involve a prosthetic component that is fixed with a tightening screw.
Once the screw connecting the implant to the prosthesis has been tightened, in order to prevent the cement (cemented prosthesis) or composite (screwed prosthesis) from occluding the head of the tightening screw, it is necessary to protect the screw with a cavity material.
However, the dental industry has never considered this necessity and provided solutions that could meet clinical needs in compliance with current regulations and available literature; clinicians have adapted to using materials that have not been developed for this purpose. Therefore, over the years different materials have been used, including a common or banal cotton wool pad (perhaps soaked in antibiotic or mouthwash), plumber’s Teflon tape, gutta-percha and impression silicone.
None of these materials, of course, is certified for such use (gutta-percha is certified for use in endodontics but not for prosthetics (art.16/c)) nor could it be, as it would never meet the stringent requirements of the European Regulations.
Most clinicians are convinced that the use of these materials is harmless for the patient and permitted by law, as they are widely used and even published in several scientific articles. Formally, and also substantively, it is exactly the opposite.
The directive clearly states that the very fact that a product is used on a patient qualifies that product as a medical device. Whoever inserts a second medical device (e.g. Teflon in the screw access channel) into a main medical device (crown or abutment or Multi-Unit Abutments) is considered, for legal purposes, to be the manufacturer of a new non-certified medical device (Art. 22 para. 4) and, at the same time, the person who puts it into service (Art. 5 para. 4). This action is, as such, punishable irrespective of whether or not the material may be harmful to the patient. Modifying a certified device, such as the implant-prosthetic system, by adding a non-certified device, such as Teflon or cotton or any other material, even certified but for a different use, therefore renders the entire device illegal.
This circumstance is the responsibility of the operator who manufactured and used the non-certified device and, in our opinion, also of the medical director (or manager) who allowed the device to be used in the first place.
This is the responsibility of the operator who manufactured and used the uncertified device and, in our view, also of the medical director (or manager), who allowed this activity to take place in breach of his supervisory duties. Finally, the liability of the owner of the facility where the offence was committed (placing a non-certified device on a patient) should be assessed. On the other hand, the European directive obliges Member States to provide for sanctions that are “effective, proportionate and dissuasive in the event of infringement.” The deadline for European states to put in place such sanctions is 25 February 2022.
These dissuasive sanctions are applicable to all implant prostheses in which non-certified devices (Teflon, cotton, impression material, gutta-percha, etc.) have been inserted.
It can therefore be clearly stated that non-certified medical devices, used as sealants in the case described, not only fail to comply with the rules on manufacturing, packaging and making available on the market, but also contravene the indications contained in Regulation 745/2017, Annex I Chapter 2 11:
“The devices and their manufacturing processes shall be designed in such a way as to eliminate or reduce as far as possible the risks of infection for patients. The design shall be such as to: … reduce as far as possible any microbial leakage from the device and/or microbial exposure during use, and … prevent microbial contamination of the device or its contents, such as samples or fluids”.
The problem of crevicular fluid penetration from the periodontal sulcus through the micro-gap between the implant (whatever the connection) and the prosthetic component is well known. Through this gap, bacteria colonise the non-certified medical devices used to seal the access tunnel to the screw. In the absence of oxygen and due to the abundance of nutrients, colonies of anaerobic bacteria are selected, which are known to be associated with the onset of peri-implant disease. These bacteria contaminate the various ‘sealant’ materials from the very first hours of prosthetic installation, using them as a substrate.
Doctor Himal Hirani (UCLAN University of Central Lancashire) recently selected in a meta-analysis the 5 papers published to date on bacterial contamination of materials commonly used as sealants (Alshehri & Albaquiah 2017, Cavalcanti et al 2015, Davis 2017, Nascimiento et al 2015, Raab et al 2017) demonstrating that:
“Micrograps are present in any design of two-piece implants and thus the abi- lity of the internal occluding material is an influential aspect in reducing this microbial activity”.
The presence of bacteria, which is inevitable in a two-piece implant, is a common experience for all clinicians who experience a characteristic smell of putrefaction when reopening the access chamber to the clamping screw.
The issue is significant not only from a clinical point of view, i.e. in terms of the overall quality of the service, but also from a forensic odontological/medical-legal point of view.
If, in fact, in a dispute centred on activities of an implant-prosthetic nature, the use of non-certified materials were to emerge where the law instead indicates strict and compulsory prescriptions for the use of materials (i.e. medical and certified devices), the violation of appropriate and congruous professional conduct would ipso facto appear evident. Nor could the circumstance that the use of non-certified material is possible in the event of an emergency or experimentation during scientific research be a valid justification for the restrictions and guidelines dictated by the aforementioned regulation.
This behaviour is even more questionable because the dentist is duly and perfectly aware that the use of non-certified materials can cause damage to the patient. Therefore, not only does the professional use (technically put into service) a material that is not a certified medical device, in contravention of the law in force, but he acts aware of the fact that such material is clinically harmful and can therefore produce negative effects (*).
In the circular of the Ministry of Health of 12 November entitled “Indications concerning certain aspects of Regulation (EU) 2017/745” by the General Directorate for Medical Devices and Pharmaceutical Service sent to all operators in the supply chain and to trade associations, including the FNOMCeO, and to the control bodies, including the NAS and the Carabinieri Command for the protection of Health, it is recalled that the European Regulation 745/2017 is fully operational and in the parts in which the national States have not yet adapted, the provisions previously in force described in Legislative Decrees 46/97 and 507/92 apply. As regards the sanctions part, those provided for in paragraph 7 of Article 23 of Legislative Decree 46/97 are valid for anyone who places on the market, makes available or puts into service medical devices without EC marking or without EC certificate:
“Whoever places on the market or puts into service medical devices lacking the EC marking or the certificate of conformity is punished, unless the fact is foreseen as a crime, with the pecuniary administrative sanction of the payment of a sum from thirty million lire to one hundred and eighty million lire.”
Such behaviour undoubtedly also exposes the practitioner to the risk of insurance cover not being activated, or being denied, for having engaged in conduct that is in fact unlawful.
An assessment in this sense would invalidate the implant-prosthetic procedure as a whole, if only because of the unjustified circumstance of the choice of using an improper material instead of a suitable and certified material, which in the overall rehabilitation activity does not affect either the economic cost (negligible) or the operational difficulty, on the contrary making the clinical activity even more simplified.
more info: Regulation (EU) 2017/745