periodontology periodontology periodontology or periodontics (from ancient greek περί, perí – 'around'; and ὀδούς, odoús – 'tooth', genitive ὀδόντος, odóntos) is the specialty of dentistry that studies supporting structures of teeth, as well as diseases and conditions that affect them. the supporting tissues are known as the periodontium, which includes the gingiva (gums), alveolar bone, cementum, and the periodontal ligament. a periodontist is a dentist that specializes in the prevention, diagnosis and treatment of periodontal disease and in the placement of dental implants. periodontistoccupationoccupation typespecialtyactivity sectorsdentistrydescriptioneducation requireddental degreefields ofemploymenthospitals, private practices the periodontium a diagram of the periodontium. a. enamel b. dentine c. alveolar bone d. oral epithelium e. attached gingiva f. gingival margin g. gingival sulcus h. junctional epithelium i. alveolar crest fibres of periodontal ligament j. horizontal fibres of pdl k. oblique fibres of pdl the term periodontium is used to describe the group of structures that directly surround, support and protect the teeth. the periodontium is composed largely of the gingival tissue and the supporting bone. gingivae normal gingiva may range in color from light coral pink to heavily pigmented. the soft tissues and connective fibres that cover and protect the underlying cementum, periodontal ligament and alveolar bone are known as the gingivae. the gingivae are categorized into three anatomical groups: the free, attached and the interdental gingiva. each of the gingival groups are considered biologically different; however, they are all specifically designed to help protect against mechanical and bacterial destruction. free gingiva the tissues that sit above the alveolar bone crest are considered the free gingiva. in healthy periodontium, the gingival margin is the fibrous tissue that encompasses the cemento-enamel junction, a line around the circumference of the tooth where the enamel surface of the crown meets the outer cementum layer of the root. a natural space called the gingival sulcus lies apically to the gingival margin, between the tooth and the free gingiva. a non-diseased, healthy gingival sulcus is typically 0.5-3mm in depth, however, this measurement can increase in the presence of periodontal disease. the gingival sulcus is lined by a non-keratinised layer called the oral sulcular epithelium; it begins at the gingival margin and ends at the base of the sulcus where the junctional epithelium and attached gingiva begins. attached gingiva the junctional epithelium is a collar-like band that lies at the base of the gingival sulcus and surrounds the tooth; it demarcates the areas of separation between the free and attached gingiva. the junctional epithelium provides a specialized protective barrier to microorganisms residing around the gingival sulcus. collagen fibres bind the attached gingiva tightly to the underlying periodontium including the cementum and alveolar bone and vary in length and width, depending on the location in the oral cavity and on the individual. the attached gingiva lies between the free gingival line or groove and the mucogingival junction. the attached gingiva dissipates functional and masticatory stresses placed on the gingival tissues during common activities such as mastication, tooth brushing and speaking.: 80–81 in health it is typically pale pink or coral pink in colour and may present with surface stippling or racial pigmentation. interdental gingiva the interdental gingiva takes up the space beneath a tooth contact point, between two adjacent teeth. it is normally triangular or pyramidal in shape and is formed by two interdental papillae (lingual and facial). the middle or centre part of the interdental papilla is made up of attached gingiva, whereas the borders and tip are formed by the free gingiva. the central point between the interdental papillae is called the col. it is a valley-like or concave depression that lies directly beneath the contact point, between the facial and lingual papilla. however, the col may be absent if there is gingival recession or if the teeth are not contacting. the main purpose of the interdental gingiva is to prevent food impaction during routine mastication. alveolar mucosa this area of tissue is non-keratinized and is located beyond the mucogingival junction. it is less firmly attached and is redder than attached gingiva. it provides for the movement of cheek and lips. periodontal ligament the periodontal ligament is the connective tissue that joins the outer layer of the tooth root, being the cementum, to the surrounding alveolar bone. it is composed of several complex fibre groups that run in different directions and which insert into the cementum and bone via sharpey's fibres. the periodontal ligament is composed mostly of collagen fibres, however it also houses blood vessels and nerves within loose connective tissue. mechanical loads that are placed on the teeth during mastication and other external forces are absorbed by the periodontal ligament, which therefore protects the teeth within their sockets. alveolar bone in periodontal health, the alveolar bone surrounds the teeth and forms the bony socket that supports each tooth. the buccal and lingual plates and lining of the sockets are composed of thin, yet dense compact or cortical bone. within the cortical plates and dental sockets lies cancellous bone, a spongy or trabecular-type bone which is less dense than compact bone. the anatomic landmarks of the alveolar process includes the lamina dura, the alveolar crest, and the periodontal ligament space. cementum cementum is the outer layer of the tooth root; it overlies the dentine layer of the tooth and provides attachment for the collagen fibres of the periodontal ligament. it also protects the dentine and provides a seal for the otherwise exposed ends of the dentinal tubules. it is not as hard as enamel or dentine and is typically a light yellow colour. gingival diseases gingivitis is a common condition that affects the gingiva or mucosal tissues that surround the teeth. the condition is a form of periodontal disease; however, it is the least devastating, in that it does not involve irreversible damage or changes to the periodontium (gingiva, periodontal ligament, cementum or alveolar bone). it is commonly detected by patients when gingival bleeding occurs spontaneously during brushing or eating. it is also characterized by generalized inflammation, swelling, and redness of the mucosal tissues. gingivitis is typically painless and is most commonly a result of plaque biofilm accumulation, in association with reduced or poor oral hygiene. other factors may increase a person's risk of gingivitis, including but not limited to systemic conditions such as uncontrolled diabetes mellitus and some medications. the signs and symptoms of gingivitis can be reversed through improved oral hygiene measures and increased plaque disruption. if left untreated, gingivitis has the potential to progress to periodontitis and other related diseases that are more detrimental to periodontal and general health. periodontal diseases periodontal disease encompasses a number of diseases of the periodontal tissues that result in attachment loss and destruction of alveolar bone. periodontal diseases take on many different forms but are usually a result of a coalescence of bacterial plaque biofilm accumulation of the red complex bacteria (e.g. p. gingivalis, t. forsythia, and t. denticola) of the gingiva and teeth, combined with host immuno-inflammatory mechanisms and other risk factors that can lead to destruction of the supporting bone around natural teeth. untreated, these diseases can lead to alveolar bone loss and tooth loss. as of 2013, periodontal disease accounted for 70.8% of teeth lost in patients with the disease in south korea. periodontal disease is the second most common cause of tooth loss (second to dental caries) in scotland. twice-daily brushing and flossing are a way to help prevent periodontal diseases. healthy gingiva can be described as stippled, pale or coral pink in caucasian people, with various degrees of pigmentation in other races. the gingival margin is located at the cemento-enamel junction without the presence of pathology. the gingival pocket between the tooth and the gingival should be no deeper than 1–3mm to be considered healthy. there is also the absence of bleeding on gentle probing. periodontal diseases can be caused by a variety of factors, the most prominent being dental plaque. dental plaque forms a bacterial biofilm on the tooth surface; if not adequately removed from the tooth surface in close proximity to the gingiva, a host-microbial interaction gets underway. this results in the imbalance between host and bacterial factors which can in turn result in a change from health to disease. other local or systemic factors can result in or further progress the manifestation of periodontal disease. other factors can include age, socio-economic status, oral hygiene education and diet. systemic factors may include uncontrolled diabetes or tobacco smoking. signs and symptoms of periodontal disease: bleeding gums, gingival recession, halitosis (bad breath), mobile teeth, ill-fitting dentures and buildup of plaque and calculus. individual risk factors include: gender, smoking and alcohol consumption, diabetes, obesity and metabolic syndrome, osteoporosis and vitamin d conditions, stress and genetic factors. 2018 aap/efp classification of periodontal and peri-implant diseases and conditions in 2017 the american academy of periodontology (aap) and the european federation of periodontology (efp) together collaborated to revise and adopt a new classification system for periodontal conditions to aid in a more personalized approach to patient care. in 2018 they released an updated classification system which includes a multi-dimensional staging and grading system for periodontitis classification, a recategorization of various forms of periodontitis, and the inaugural classification for peri-implant diseases and conditions. periodontal health, gingivitis, and gingival diseases and conditions healthy gingiva gingivitis after treatment the 2018 disease classification for periodontal health, gingivitis, and gingival diseases and conditions are outlined in detail below:: 81 periodontal health and gingival health clinical gingival health on an intact periodontium clinical gingival health on a reduced periodontium stable periodontitis patient non-periodontitis patient gingivitis—dental biofilm-induced associated with dental biofilm alone medicated by systemic or local risk factors drug-influenced gingival enlargement gingival diseases—nondental biofilm-induced genetic or developmental disorders specific infections inflammatory and immune conditions reactive processes neoplasms endocrine, nutritional, and metabolic diseases traumatic lesions gingival pigmentation disease classification for the three major forms of periodontitis periodontal recession on maxillary central incisors bone loss in periapical radiograph 2018 disease classification of periodontal diseases and conditions breaks down the category of periodontitis into three forms and each of these forms are further broken down into two or more subcategories. necrotizing periodontal diseases necrotizing gingivitis necrotizing periodontitis necrotizing stomatitis periodontitis as manifestation of systemic diseases – classification of these conditions should be based on the primary systemic disease according to the international statistical classification of diseases and related health problems (icd) codes periodontitis stages: based on severity and complexity of management stage i: initial periodontitis stage ii: moderate periodontitis stage iii: severe periodontitis with potential for additional tooth loss stage iv: severe periodontitis with potential for loss of the dentition extent and distribution: localized, generalized; molar-incisor distribution grades: evidence or risk of rapid progression, anticipated treatment response grade a: slow rate of disease progression grade b: moderate rate of disease progression grade c: rapid rate of disease progression other conditions affecting the periodontium abscessed tooth periapical radiograph the 2018 disease classification of periodontal disease and conditions contains a category for other conditions that may have an effect upon the health of the periodontium. systemic diseases or conditions affecting the periodontal supporting tissues other periodontal conditions periodontal abscesses endodontic periodontal lesions mucogingival deformities and conditions around teeth gingival phenotype gingival/soft tissue recession lack of gingiva decreased vestibular depth aberrant frenum or muscle position gingival excess abnormal colour condition of exposed root surface traumatic occlusal forces primary occlusal trauma secondary occlusal trauma orthodontic forces prostheses and tooth-related factors that modify or predispose to plaque-induced gingival diseases/periodontitis localized tooth-related factors localized dental prostheses-related factors peri-implant diseases and conditions the 2018 disease classification of periodontal disease and conditions divides this category into four subcategories: peri-implant health peri-implant mucositis peri-implantitis peri-implant soft and hard tissue deficiencies prevention the most effective prevention method is what can be achieved by the patient at home, for example, using the correct tooth brushing technique, interdental cleaning aids such as interdental brushes or floss and using a fluoridated toothpaste. it is also advised that patients receive bi-annual check ups from their dental health provider along with thorough cleaning. treatment along with specialist periodontist treatment, a general dentist or dental hygienist can perform routine scale and cleans using either hand instruments or an ultrasonic scaler (or a combination of both). the practitioner can also prescribe specialized plaque-removal techniques (tooth brushing, interdental cleaning). the practitioner can also perform a