28 GENERAL DENTISTRY Dental Tribune Middle East & Africa Edition | 4/2019 Biological Dentistry By Dr. Carla Schweer, France Biological dentistry is a more bio- compatible approach to oral health and offers alternative therapy to conventional dentistry. It regards the patient as a whole and does not treat the mouth in isolation. What hap- pens to the teeth and gingivae has an impact on the rest of the body, and conversely, a systemic condi- tion can affect oral health. Teeth are often a reflection of a general state of health. It involves a more organic approach to care, with less-invasive protocols and materials. Biological dentists always seek the safest, least toxic way to accomplish the mission of therapy and all the goals of mod- ern dentistry. Biological dentistry describes a philosophy that can ap- ply to all facets of dental practice and healthcare in general. Oral ecology The human mouth contains around 500–1,000 different types of bac- teria with various functions as part of the human flora and oral micro- biology. Individuals who practise oral hygiene have 1,000 to 100,000 bacteria living on each tooth surface, while less clean mouths can have between 100 million and one billion bacteria on each tooth.1 Some of the bacteria in our mouths are harmful and can cause serious illness, while others are beneficial and prevent dis- ease. Periodontal treatment is an es- sential aspect of biological dentistry to prevent diseases such as diabetes, cardiovascular disease, rheumatoid arthritis, metabolic syndrome and Alzheimer’s disease.2–4 Immune system The biological dentist will give the patient nutritional advice and pre- scribe vitamins and food supple- ments to enhance the immune sys- tem for a better outcome of therapy. For example, in biological dentistry, it is commonly known that a high vitamin D level and low LDL choles- terol are key factors for a better out- come for bone surgery and implant osseointegration.5 Dental mercury An amalgam restoration is of great concern to biological dentists. This is because 50% of it consists of mer- cury, which is one of the most toxic non-radioactive elements on the planet. Therefore, biological den- tists feel that it has no place in the human mouth. Scientific evidence has established beyond any doubt that amalgam continuously releases mercury in small amounts and cre- ates measurable exposure in people with amalgam restorations.6 Chronic exposure to mercury could be det- rimental to their health. Mercury is stored within the brain and other parts of the central nervous system, as well as in the liver, kidneys, large intestine, fat tissue and thyroid gland.7, 8 Biological dentists follow science- based procedures to minimise mer- cury exposure during amalgam removal9 and use special containers and collectors to avoid pollution of the environment. At Dr Roze & As- sociates, we use the Safe Mercury Amalgam Removal Technique, a pro- tocol designed by the International Academy of Oral Medicine and Toxi- cology (https://thesmartchoice.com; Fig. 1) Metals and oral galvanism Biological dentists believe that placing metal and other foreign materials in the teeth and gingivae may have un- intended consequences. That is why biological dentists only offer metal- free alternatives such as ceramics or composites. Composites are also chosen with care, as they should be methacrylate-free and non-allergenic. Consequently, they are free of HEMA, bis-GMA and TEGDMA. A bridge framework and titanium implants are replaced by a zirconia alternative, which has better biosta- bility and great osseointegration and is non-corrosive, non-conductive, hypo-allergenic and more aesthetic. These implants contain zirconia, a biocompatible ceramic material free of metal. These types of implants promote complete assimilation into the jawbone and the surrounding gingivae.10, 11 Aside from their ability to provoke immune reactivity, metals are elec- trically active. Oral galvanism has been discussed for well over 100 years, but dentists have tended to ig- nore it and its implications.12 Biologi- cal macromolecules can influence the rate of corrosion by interfering in different ways with anodic or ca- thodic reactions. When combined with mechanics (such as static load- ing, dynamic loading or wear) and in- flammation, corrosion is intensified. The corrosion behaviour of a metal in non-physiological in vitro studies versus physiological in vitro studies and versus in vivo studies may vary dramatically. The corrosion control in vivo is currently limited to care- ful design, proper material selection, and surface modification. The effec- tiveness of coatings may be limited in vivo due to wear (Fig. 3).13 Endodontic treatment Endodontically treated teeth are dead tissue left in the body. This type of procedure is not found in any other medical discipline. Inflamma- tion is common at the root apex, as it is almost impossible to clean thor- oughly in this area. Even the best en- dodontic specialist can never achieve a complete cleansing free of bacteria. Accessory lateral channels and the endodontic-periodontal connection via the dentinal tubules remain un- sealed.14 Thus, bacteria harboured in root canal areas such as isthmuses, dentinal tubules and ramifications may evade disinfectants.15 These pathogenic bacteria produce toxic and potentially carcinogenic hydro- gen sulphide compounds (thioether and mercaptans) from the amino acids cysteine and methionine as by- products of anaerobic metabolism. Studies have reported several differ- ent strains of bacteria found in en- dodontically treated teeth with peri- apical periodontitis.16 Enterococcus faecalis and yeast, mainly Candida albicans, are very resistant and have been repeatedly identified as the spe- cies most commonly recovered from root canals undergoing retreatment, in cases of failed endodontic therapy and canals with persistent infec- tions.17 The predominance of Gram- negative anaerobes associated with endodontic infections and evidence of cytokine production in inflamed pulp and periapical granulomatous tissue has shown an elevation of systemic levels of inflammatory me- diators in endodontic patients which could have an impact on distant or- gans.18 Fig: 1 Fig: 2 Since the human body and its robust immune system can compensate relatively well, and conventional medicine does not consider the body to be an integrative system and focuses much more on its parts, the link between the oral cavity and symptoms elsewhere in the body has not been well established. The biological dentist takes this re- lation very seriously and watches endodontically teeth closely. The best way to diagnose inflammation of the root apex is to rely on 3-D ra- diographic imaging (CBCT). It has been shown that in many cases it can detect periapical periodontitis where 2-D radiograph shows a sound pic- ture (Fig. 4). Cavitation or jawbone osteonecrosis Cavitation or ischaemic osteone- crosis describes a disease process in which the lack of blood supply (is- chaemia) to an area of bone results in a dead portion of the jawbone. It can also occur in other bones of the body. Neuralgia-inducing cavitation- al osteonecrosis (NICO) is similar, but produces neuralgic facial pain. In the simplest terms, cavitation is a hole in the jawbone, occurring mainly after a tooth extraction that has not healed correctly. Dr Greene Vardiman Black, one of the found- ers of modern dentistry, described this process as early as 1915.19 Patho- gens, a biofilm form of bacteria, are also present in this dead tissue and release highly toxic waste products that can pass into the bloodstream and have detrimental effects on the heart, kidney and joints, as well as the immune, nervous and endocrine systems. Recent work in the field of facial pain syndromes and NICO has led to the realisation that the jawbones are a frequent site of ischaemic osteone- crosis. This can be called aseptic ne- crosis and also affects the femoral head. As a result, many extraction sites that appear to have healed have actually not healed completely. It can trigger pain in other parts of the face and head, and in distant parts of the body. Even though most of these sites present with no symptoms at all, pathological examination reveals a combination of dead bone and slowly growing anaerobic pathogens in a mixture of highly toxic waste products where there otherwise ap- pears to be proper healing. Blame for these infections has been placed on the periodontal ligament left behind after extraction. How- ever, it is most likely that cavitation occurs as a result of a combination of initiating events, predisposing risk factors and environmental factors. Notably, if patients have infections after their extractions or experience traumatic events such as dry sockets, there is a higher likelihood of cavita- tion development. Usually in these cases, the wound has not been thor- oughly cleaned and sterilised. An ef- fective way to sterilise the extraction socket is by using laser and ozone. Biological dentistry today Dentistry is a rapidly evolving field. Especially, biological dentistry is al- ways seeking the latest research for a better and safer approach. In the past, it was revolutionary to be able to restore a tooth instead of just pull- ing it out; amalgam, gold and den- ture teeth were, at the time, innova- tive materials and a better option than extraction. But today, we can do better dentistry in a less toxic, more individualised, more integrated and more environmentally friendly way than ever. Biological dentistry is a mindset more than a specialty. It could also be called advisory dentist- ry or common sense dentistry. When dentists choose to put biocompat- ibility first, they can look forward to practising effective dentistry while knowing that patients are provided with the safest experience for their overall health. Fig: 3 References 1. Stevens JE. Oral ecology. MITS Tech- nol Rev. 1997 Jan 1;100:48–55. 2. Preshaw PM, Alba AL, Herrera D, Jepsen S, Konstantinidis A, Makrila- kis K, Taylor R. Periodontitis and dia- betes: a two-way relationship. Diabe- tologia. 2012 Jan;55(1):21–31. 3. Dhadse, P, Gattani, D, Mishra R. The link between periodontal disease and cardiovascular disease: How far we have come in last two dec- ades? J Indian Soc Periodontol. 2010 Jul;14(3):148–54. 4. Dominy SS, Lynch C, Ermini F, Benedyk M, Marczyk A, Konradi A, Nguyen M, Haditsch U, Raha D, Grif- fin C, Holsinger LJ, Arastu-Kapur S, Kaba S, Lee A, Ryder MI, Potempa B, Mydel P, Hellvard A, Adamowicz K, Hasturk H, Walker GD, Reynolds EC, Faull RL, Curtis MA, Dragunow M, Potempa J. Porphyromonas gingivalis in Alzheimer’s disease brains: Evidence for disease causa- tion and treatment with small-mol- ecule inhibitors. Sci Adv. 2019 Jan 23;5(1):eaau3333. doi: 10.1126/sciadv. aau3333. 5. Choukroun J, Khoury G, Khoury F, Russe P, Testori T, Komiyama Y, Sammartino G, Palacci P, Tunali M, Choukroun E. Two neglected biologic risk factors in bone grafting and im- plantology: high low-density lipo- protein cholesterol and low serum vitamin D. J Oral Implantol. 2014 Feb;40(1):110–4. 6. Krausß P, Deyhle M, Maier KH, Roller E, Weiß HD, Cledon P. Field study on the mercury content of saliva. Toxicol Environ Chem. 1997 Sep;63(1–4):29–46. 7. Eggleston DW, Nylander M. Corre- lation of dental amalgam with mer- cury in brain tissue. J Prosthet Dent. 1987 Dec;58(6):704–7. 8. Danscher G, Hørsted-Bindslev P, Rungby J. Traces of mercury in organs from primates with amal- gam fillings. Exp Mol Pathol. 1990 Jun;52(3):291–9. Editorial note: A list of references can be obtained from the publisher. About the Author Dr Carla Schweer IAOMT biological dentist and CAD/CAM specialist