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There are two main methods of detecting dental plaque in the oral cavity: through the application of a disclosing gel or tablet, and/or visually through observation. Plaque detection is usually detected clinically by plaque disclosing agents. Disclosing agents contain dye which turns bright red to indicate plaque build-up.
It is important for an individual to be aware of what to look for when doing a self-assessment for dental plaque. It is important to be aware that everyone has dental plaque, however, the severity of the build-up and the consequences of not removing the plaque can vary.
Plaque disclosing products, also known as disclosants, make plaque clinically visible. Clean surfaces of the teeth do not absorb the disclosant, only rough surfaces. Plaque disclosing gels can be either completed at home or in the dental clinic. Before using these at home or in the dental clinic check with your general practitioners for any allergies to iodine, food colouring or any other ingredients that may be present in these products. These gels provide a visual aid in assessing plaque biofilm presence and can also show the maturity of the dental plaque.
Daily oral hygiene measures to prevent periodontal disease include:
- Brushing properly on a regular basis (at least twice daily), with the patient attempting to direct the toothbrush bristles underneath the gumline, helps disrupt the bacterial-mycotic growth and formation of subgingival plaque.
- Flossing daily and using interdental brushes (if the space between teeth is large enough), as well as cleaning behind the last tooth, the third molar, in each quarter
- Using an antiseptic mouthwash: Chlorhexidine gluconate-based mouthwash in combination with careful oral hygiene may cure gingivitis, although they cannot reverse any attachment loss due to periodontitis.
- Using periodontal trays to maintain dentist-prescribed medications at the source of the disease: The use of trays allows the medication to stay in place long enough to penetrate the biofilms where the microorganism are found.
- Regular dental check-ups and professional teeth cleaning as required: Dental check-ups serve to monitor the person's oral hygiene methods and levels of attachment around teeth, identify any early signs of periodontitis, and monitor response to treatment.
- Microscopic evaluation of biofilm may serve as a guide to regaining commensal health flora.
Typically, dental hygienists (or dentists) use special instruments to clean (debride) teeth below the gumline and disrupt any plaque growing below the gumline. This is a standard treatment to prevent any further progress of established periodontitis. Studies show that after such a professional cleaning (periodontal debridement), microbial plaque tends to grow back to precleaning levels after about three to four months. Nonetheless, the continued stabilization of a patient's periodontal state depends largely, if not primarily, on the patient's oral hygiene at home, as well as on the go. Without daily oral hygiene, periodontal disease will not be overcome, especially if the patient has a history of extensive periodontal disease.
Periodontal disease and tooth loss are associated with an increased risk, in male patients, of cancer.
Contributing causes may be high alcohol consumption or a diet low in antioxidants.
Prevention of pericoronitis can be achieved by removing impacted third molars before they erupt into the mouth, or through preemptive operculectomy. A treatment controversy exists about the necessity and timing of the removal of asymptomatic, disease-free impacted wisdom teeth which prevents pericoronitis. Proponents of early extraction cite the cumulative risk for extraction over time, the high probability that wisdom teeth will eventually decay or develop gum disease and costs of monitoring to retained wisdom teeth. Advocates for retaining wisdom teeth cite the risk and costs of unnecessary operations and the ability to monitor the disease through clinical exam and radiographs.
Periodontal abscesses may be difficult to distinguish from periapical abscesses. Since the management of a periodontal abscess is different from a periapical abscess, this differentiation is important to make (see Dental abscess#Diagnostic approach) For example, root canal therapy is unnecessary and has no impact on pain in a periodontal abscess.
Gingivitis is a category of periodontal disease in which there is no loss of bone but inflammation and bleeding are present.
Each tooth is divided into four gingival units (mesial, distal, buccal, and lingual) and given a score from 0-3 based on the gingival index. The four scores are then averaged to give each tooth a single score.
The diagnosis of the periodontal disease gingivitis is done by a dentist. The diagnosis is based on clinical assessment data acquired during a comprehensive periodontal exam. Either a registered dental hygienist or a dentist may perform the comprehensive periodontal exam but the data interpretation and diagnosis are done by the dentist. The comprehensive periodontal exam consists of a visual exam, a series of radiographs, probing of the gingiva, determining the extent of current or past damage to the periodontium and a comprehensive review of the medical and dental histories.
Current research shows that activity levels of the following enzymes in saliva samples are associated with periodontal destruction: aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma glutamyl transferase (GGT), alkaline phosphatase (ALP), and acid phosphatase (ACP). Therefore, these enzyme biomarkers may be used to aid in the diagnosis and treatment of gingivitis and periodontitis.
A dental hygienist or dentist will check for the symptoms of gingivitis, and may also examine the amount of plaque in the oral cavity. A dental hygienist or dentist will also look for signs of periodontitis using X-rays or periodontal probing as well as other methods.
If gingivitis is not responsive to treatment, referral to a periodontist (a specialist in diseases of the gingiva and bone around teeth and dental implants) for further treatment may be necessary.
Dentists and dental hygienists measure periodontal disease using a device called a periodontal probe. This thin "measuring stick" is gently placed into the space between the gums and the teeth, and slipped below the gumline. If the probe can slip more than below the gumline, the patient is said to have a gingival pocket if no migration of the epithelial attachment has occurred or a periodontal pocket if apical migration has occurred. This is somewhat of a misnomer, as any depth is, in essence, a pocket, which in turn is defined by its depth, i.e., a 2-mm pocket or a 6-mm pocket. However, pockets are generally accepted as self-cleansable (at home, by the patient, with a toothbrush) if they are 3 mm or less in depth. This is important because if a pocket is deeper than 3 mm around the tooth, at-home care will not be sufficient to cleanse the pocket, and professional care should be sought. When the pocket depths reach in depth, the hand instruments and cavitrons used by the dental professionals may not reach deeply enough into the pocket to clean out the microbial plaque that causes gingival inflammation. In such a situation, the bone or the gums around that tooth should be surgically altered or it will always have inflammation which will likely result in more bone loss around that tooth. An additional way to stop the inflammation would be for the patient to receive subgingival antibiotics (such as minocycline) or undergo some form of gingival surgery to access the depths of the pockets and perhaps even change the pocket depths so they become 3 mm or less in depth and can once again be properly cleaned by the patient at home with his or her toothbrush.
If patients have 7-mm or deeper pockets around their teeth, then they would likely risk eventual tooth loss over the years. If this periodontal condition is not identified and the patients remain unaware of the progressive nature of the disease, then years later, they may be surprised that some teeth will gradually become loose and may need to be extracted, sometimes due to a severe infection or even pain.
According to the Sri Lankan tea laborer study, in the absence of any oral hygiene activity, approximately 10% will suffer from severe periodontal disease with rapid loss of attachment (>2 mm/year). About 80% will suffer from moderate loss (1–2 mm/year) and the remaining 10% will not suffer any loss.
The College of Registered Dental Hygienists of Alberta (CRDHA) defines a dental hygienist as "a health care professional whose work focuses on the oral health of an individual or community." These dental professionals aim to improve oral health by educating patients on the prevention and management of oral disease. Dental hygienists can be found performing oral health services in various settings, including private dental offices, schools, and other community settings, such as long-term care facilities. As mentioned above in the clinical significance section, plaque and calculus deposits are a major etiological factor in the development and progression of oral disease. An important part of the scope of practice of a dental hygienist is the removal of plaque and calculus deposits. This is achieved through the use of specifically designed instruments for debridement of tooth surfaces. Treatment with these types of instruments is necessary as calculus deposits cannot be removed by brushing or flossing alone. To effectively manage disease or maintain oral health, thorough removal of calculus deposits should be completed at frequent intervals. The recommended frequency of dental hygiene treatment can be made by a registered professional, and is dependent on individual patient needs. Factors that are taken into consideration include an individual's overall health status, tobacco use, amount of calculus present, and adherence to a professionally recommended home care routine.
Hand instruments are specially designed tools used by dental professionals to remove plaque and calculus deposits that have formed on the teeth. These tools include scalers, curettes, jaquettes, hoes, files and chisels. Each type of tool is designed to be used in specific areas of the mouth. Some commonly used instruments include sickle scalers which are designed with a pointed tip and are mainly used supragingivally. Curettes are mainly used to remove subgingival calculus, smooth root surfaces and to clean out periodontal pockets. Curettes can be divided into two subgroups: universals and area specific instruments. Universal curettes can be used in multiple areas, while area specific instruments are designed for select tooth surfaces. Gracey curettes are a popular type of area specific curettes. Due to their design, area specific curettes allow for better adaptation to the root surface and can be slightly more effective than universals. Hoes, chisels, and files are less widely used than scalers and curettes. These are beneficial when removing large amounts of calculus or tenacious calculus that cannot be removed with a curette or scaler alone. Chisels and hoes are used to remove bands of calculus, whereas files are used to crush burnished or tenacious calculus.
For hand instrumentation to be effective and efficient, it is important for clinicians to ensure that the instruments being used are sharp. It is also important for the clinician to understand the design of the hand instruments to be able to adapt them properly.
Ultrasonic scalers, also known as power scalers, are effective in removing calculus, stain, and plaque. These scalers are also useful for root planing, curettage, and surgical debridement. Not only is tenacious calculus and stain removed more effectively with ultrasonic scalers than with hand instrumentation alone, it is evident that the most satisfactory clinical results are when ultrasonics are used in adjunct to hand instrumentation. There are two types of ultrasonic scalers; piezoelectric and magnetostrictive. Oscillating material in both of these handpieces cause the tip of the scaler to vibrate at high speeds, between 18,000 and 50,000 Hz. The tip of each scaler uses a different vibration pattern for removal of calculus. The magnetostrictive power scaler vibration is elliptical, activating all sides of the tip, whereas the piezoelectric vibration is linear and is more active on the two sides of the tip.
Special tips for ultrasonic scalers are designed to address different areas of the mouth and varying amounts of calculus buildup. Larger tips are used for heavy subgingival or supragingival calculus deposits, whereas thinner tips are designed more for definitive subgingival debridement. As the high frequency vibrations loosen calculus and plaque, heat is generated at the tip. A water spray is directed towards the end of the tip to cool it as well as irrigate the gingiva during debridement. Only the first 1–2 mm of the tip on the ultrasonic scaler is most effective for removal, and therefore needs to come into direct contact with the calculus to fracture the deposits. Small adaptations are needed in order to keep the tip of the scaler touching the surface of the tooth, while overlapping oblique, horizontal, or vertical strokes are used for adequate calculus removal.
Current research on potentially more effective methods of subgingival calculus removal focuses on the use of near-ultraviolet (NUV) and near-infrared lasers, such as Er,Cr:YSGG lasers. The use of lasers in periodontal therapy offers a unique clinical advantage over conventional hand instrumentation, as the thin and flexible fibers can deliver laser energy into periodontal pockets that are otherwise difficult to access. Near-infrared lasers, such as the Er,CR:YSGG laser, have been proposed as an effective adjunct for calculus removal as the emission wavelength is highly absorbed by water, a large component of calculus deposits. An optimal output power setting of 1.0-W with the near-infrared Er,Cr:YSGG laser has been shown to be effective for root scaling. Near-ultraviolet (NUV) lasers have also shown promise as they allow the dental professional to remove calculus deposits quickly, without removing underlying healthy tooth structure, which often occurs during hand instrumentation. Additionally, NUV lasers are effective at various irradiation angles for calculus removal. Discrepancies in the efficiency of removal are due to the physical and optical properties of the calculus deposits, not to the angle of laser use. Dental hygienists must receive additional theoretical and clinical training on the use of lasers, where legislation permits.
An examination by the dentist or dental hygienist should be sufficient to rule out the issues such as malnutrition and puberty. Additional corresponding diagnosis tests to certain potential disease may be required. This includes oral glucose tolerance test for diabetes mellitus, blood studies, human gonadotrophin levels for pregnancy, and X-rays for teeth and jaw bones.
In order to determine the periodontal health of a patient, the dentist or dental hygienist records the sulcular depths of the gingiva and observes any bleeding on probing. This is often accomplished with the use of a periodontal probe. Alternatively, dental floss may also be used to assess the Gingival bleeding index. It is used as an initial evaluation on patient's periodontal health especially to measure gingivitis. The number of bleeding sites is used to calculate the gingival bleeding score.
Peer-reviewed dental literature thoroughly establishes that bleeding on probing is a poor positive predictor of periodontal disease, but conversely lack of bleeding is a very strong negative predictor. The clinical interpretation of this research is that while BOP presence may not indicate periodontal disease, continued absence of BOP is a strong predictor (approximately 98%) of continued periodontal health.
Any tooth that is identified, in either the history of pain or base clinical exam, as a source for toothache may undergo further testing for vitality of the dental pulp, infection, fractures, or periodontitis. These tests may include:
- Pulp sensitivity tests, usually carried out with a cotton wool sprayed with ethyl chloride to serve as a cold stimulus, or with an electric pulp tester. The air spray from a three-in-one syringe may also be used to demonstrate areas of dentin hypersensitivity. Heat tests can also be applied with hot Gutta-percha. A healthy tooth will feel the cold but the pain will be mild and disappear once the stimulus is removed. The accuracy of these tests has been reported as 86% for cold testing, 81% for electric pulp testing, and 71% for heat testing. Because of the lack of test sensitivity, a second symptom should be present or a positive test before making a diagnosis.
- Radiographs utilized to find dental caries and bone loss laterally or at the apex.
- Assessment of biting on individual teeth (which sometimes helps to localize the problem) or the separate cusps (may help to detect cracked cusp syndrome).
Less commonly used tests might include trans-illumination (to detect congestion of the maxillary sinus or to highlight a crack in a tooth), dyes (to help visualize a crack), a test cavity, selective anaesthesia and laser doppler flowmetry.
Discoloration of the front teeth is one of the most common reasons people seek dental care. However, many people with teeth of normal shade ask for them to be whitened. Management of tooth discoloration depends on the cause. Most discoloration is harmless and may or may not be of cosmetic concern to the individual. In other cases it may indicate underlying pathology such as pulp necrosis or rarely a systemic disorder.
Most extrinsic discoloration is readily removed by cleaning the teeth, whether with "whitening" (i.e., abrasive) toothpaste at home, or as treatment carried out by a professional (e.g., scaling and/or polishing). To prevent future buildup of extrinsic stains, identification of the cause (e.g., smoking) is required.
Intrinsic discoloration generally requires one of the many types of tooth bleaching. Alternatively the appearance of the tooth can be hidden with dental restorations (e.g., composite fillings, veneers, crowns).
The presence of dental plaque or infection beneath an inflamed operculum without other obvious causes of pain will often lead to a pericoronitis diagnosis; therefore, elimination of other pain and inflammation causes is essential. For pericoronal infection to occur, the affected tooth must be exposed to the oral cavity, which can be difficult to detect if the exposure is hidden beneath thick tissue or behind an adjacent tooth. Severe swelling and restricted mouth opening may limit examination of the area. Radiographs can be used to rule out other causes of pain and to properly assess the prognosis for further eruption of the affected tooth.
Sometimes a "migratory abscess" of the buccal sulcus occurs with pericoronal infection, where pus from the lower third molar region tracks forwards in the submucosal plane, between the body of the mandible and the attachment of the buccinator muscle to the mandible. In this scenario, pus may spontaneously discharge via an intra-oral sinus located over the mandibular second or first molar, or even the second premolar.
Similar causes of pain, some which can occur in conjunction with pericoronitis may include:
- Dental caries (tooth decay) of the wisdom tooth and of the distal surface of the second molar is common. Tooth decay may cause pulpitis (toothache) to occur in the same region, and this may cause pulp necrosis and the formation of a periapical abscess associated with either tooth.
- Food can also become stuck between the wisdom tooth and the tooth in front, termed food packing, and cause acute inflammation in a periodontal pocket when the bacteria become trapped. A periodontal abscess may even form by this mechanism.
- Pain associated with temporomandibular joint disorder and myofascial pain also often occurs in the same region as pericoronitis. They are easily missed diagnoses in the presence of mild and chronic pericoronitis, and the latter may not be contributing greatly to the individual's pain (see table).
It is rare for pericoronitis to occur in association with both lower third molars at the same time, despite the fact that many young people will have both lower wisdom teeth partially erupted. Therefore, bilateral pain from the lower third molar region is unlikely to be caused by pericoronitis and more likely to be muscular in origin.
Gingivitis can be prevented through regular oral hygiene that includes daily brushing and flossing. Hydrogen peroxide, saline, alcohol or chlorhexidine mouth washes may also be employed. In a 2004 clinical study, the beneficial effect of hydrogen peroxide on gingivitis has been highlighted.
Rigorous plaque control programs along with periodontal scaling and curettage also have proved to be helpful, although according to the American Dental Association, periodontal scaling and root planing are considered as a treatment for periodontal disease, not as a preventive treatment for periodontal disease. In a 1997 review of effectiveness data, the U.S. Food and Drug Administration (FDA) found clear evidence showing that toothpaste containing triclosan was effective in preventing gingivitis.
Most dental pain can be treated with routine dentistry. In rare cases, toothache can be a symptom representing a life-threatening condition, such as a deep neck infection (compression of the airway by a spreading odontogenic infection) or something more remote like a heart attack.
Dental caries, if left untreated, follows a predictable natural history as it nears the pulp of the tooth. First it causes reversible pulpitis, which transitions to irreversible pulpitis, then to necrosis, then to necrosis with periapical periodontitis and, finally, to necrosis with periapical abscess. Reversible pulpitis can be stopped by removal of the cavity and the placement of a sedative dressing of any part of the cavity that is near the pulp chamber. Irreversible pulpitis and pulp necrosis are treated with either root canal therapy or extraction. Infection of the periapical tissue will generally resolve with the treatment of the pulp, unless it has expanded to cellulitis or a radicular cyst. The success rate of restorative treatment and sedative dressings in reversible pulpitis, depends on the extent of the disease, as well as several technical factors, such as the sedative agent used and whether a rubber dam was used. The success rate of root canal treatment also depends on the degree of disease (root canal therapy for irreversible pulpitis has a generally higher success rate than necrosis with periapical abscess) and many other technical factors.
There is professional agreement among dentists that smoking cessation and good oral hygiene are key to effective treatment and positive outcomes for patients.
The typical initial treatment known to be effective is scaling and root planing (SRP) to mechanically debride the depths of the periodontal pocket and disrupt the biofilm present. This is done using a powered ultrasonic or sonic scaler and/or unpowered hand instruments.
"In patients with chronic periodontitis, subgingival debridement (in conjunction with supragingival plaque control) is an effective treatment in reducing probing pocket depth and improving the clinical attachment level. In fact it is more effective than supragingival plaque control alone".
Full mouth disinfection protocols are favoured by some clinicians. There is no evidence that full mouth disinfection or full mouth scaling protocols improve the outcome when compared to standard mechanical scaling and root planing.
Open flap debridement is used by some practitioners particularly in deeper pocket areas. The advantages of this approach is better visualization of the root surface to be cleaned. This must be weighed against the risks of surgery. Open flap surgery is more effective than non-surgical periodontal therapy in deep pocketing : "Both scaling and root planing alone and scaling and root planing combined with flap procedure are effective methods for the treatment of chronic periodontitis in terms of attachment level gain and reduction in gingival inflammation. In the treatment of deep pockets open flap debridement results in greater PPD reduction and clinical attachment gain."
Guided tissue regeneration (GTR) using PTFE membranes is favoured by some practitioners, despite its cost and complexity: "GTR has a greater effect on probing measures of periodontal treatment than open flap debridement, including improved attachment gain, reduced pocket depth, less increase in gingival recession and more gain in hard tissue probing at re-entry surgery. However there is marked variability between studies and the clinical relevance of these changes is unknown. As a result, it is difficult to draw general conclusions about the clinical benefit of GTR. Whilst there is evidence that GTR can demonstrate a significant improvement over conventional open flap surgery, the factors affecting outcomes are unclear from the literature and these might include study conduct issues such as bias. Therefore, patients and health professionals need to consider the predictability of the technique compared with other methods of treatment before making final decisions on use."
Enamel matrix derivative (EMD) is favoured by some practitioners despite its high cost: "One year after its application, EMD significantly improved probing attachment levels (1.1 mm) and probing pocket depth reduction (0.9 mm) when compared to a placebo or control, however, the high degree of heterogeneity observed among trials suggests that results have to be interpreted with great caution. In addition, a sensitivity analysis indicated that the overall treatment effect might be overestimated. The actual clinical advantages of using EMD are unknown. With the exception of significantly more postoperative complications in the GTR group, there was no evidence of clinically important differences between GTR and EMD. Bone substitutes may be associated with less gingival recession than EMD."
Systemic antibiotics such as amoxicillin or metronidazole are sometimes used in addition to debridement based treatments.
"Systemic antimicrobials in conjunction with scaling and root planing (SRP), can offer an additional benefit over SRP alone in the treatment of periodontitis, in terms of clinical attachment loss (CAL) and probing pocket depth (PPD) change, and reduced risk of additional CAL loss. However, differences in study methodology and lack of data precluded an adequate and complete pooling of data for a more comprehensive analyses. It was difficult to establish definitive conclusions, although patients with deep pockets, progressive or 'active' disease, or specific microbiological profile, can benefit more from this adjunctive therapy."
An important factor is whether the involved tooth is to be extracted or retained. Although the pulp is usually still vital, a history of recurrent periodontal abscesses and significantly compromised periodontal support indicate that the prognosis for the tooth is poor and it should be removed.
The initial management of a periodontal abscess involves pain relief and control of the infection. The pus needs to be drained, which helps both of these aims. If the tooth is to be removed, drainage will occur via the socket. Otherwise, if pus is already discharging from the periodontal pocket, this can be encouraged by gentle irrigation and scaling of the pocket whilst massaging the soft tissues. If this does not work, incision and drainage is required, as described in Dental abscess#Treatment.
Antibiotics are of secondary importance to drainage, which if satisfactory renders antibiotics unnecessary. Antibiotics are generally reserved for severe infections, in which there is facial swelling, systemic upset and elevated temperature. Since periodontal abscesses frequently involve anaerobic bacteria, oral antibiotics such as amoxicillin, clindamycin (in penicillin allergy or pregnancy) and/or metronidazole are given. Ideally, the choice of antibiotic is dictated by the results of microbiological culture and sensitivity testing of a sample of the pus aspirated at the start of any treatment, but this rarely occurs outside the hospital setting.
Other measures that are taken during management of the acute phase might include reducing the height of the tooth with a dental drill, so it no longer contacts the opposing tooth when biting down; and regular use of hot salt water mouth washes (antiseptic and encourages further drainage of the infection).
The management following the acute phase involves removing any residual infection, and correcting the factors that lead to the formation of the periodontal abscess. Usually, this will be therapy for periodontal disease, such as oral hygiene instruction and periodontal scaling.
Treatment for TRs is limited to tooth extraction because the lesion is progressive. Amputation of the tooth crown without root removal has also been advocated in cases demonstrated on a radiograph to be type 2 resorption without associated periodontal or endodontic disease because the roots are being replaced by bone. However, X-rays are recommended prior to this treatment to document root resorption and lack of the periodontal ligament.
Tooth restoration is not recommended because resorption of the tooth will continue underneath the restoration. Use of alendronate has been studied to prevent TRs and decrease progression of existing lesions.
If there is persistent continuation of inflammation and bleeding, a prescription of antiplaque rinse would be useful.
In dentistry, calculus or tartar is a form of hardened dental plaque. It is caused by precipitation of minerals from saliva and gingival crevicular fluid (GCF) in plaque on the teeth. This process of precipitation kills the bacterial cells within dental plaque, but the rough and hardened surface that is formed provides an ideal surface for further plaque formation. This leads to calculus buildup, which compromises the health of the gingiva (gums). Calculus can form both along the gumline, where it is referred to as supragingival ("above the gum"), and within the narrow sulcus that exists between the teeth and the gingiva, where it is referred to as subgingival ("below the gum").
Calculus formation is associated with a number of clinical manifestations, including bad breath, receding gums and chronically inflamed gingiva. Brushing and flossing can remove plaque from which calculus forms; however, once formed, it is too hard and firmly attached to be removed with a toothbrush. Calculus buildup can be removed with ultrasonic tools or dental hand instruments (such as a periodontal scaler).
Tetracycline is a broad spectrum antibiotic, and its derivative minocycline is common in the treatment of acne. The drug is able to chelate calcium ions and is incorporated into teeth, cartilage and bone. Ingestion during the years of tooth development causes a yellow-green discoloration of dentin, which is visible through the enamel and fluorescent under ultraviolet light. Later, the tetracycline oxidizes and the staining becomes more brown and no longer fluoresces under UV light. Other drugs derived from tetracycline such as glycylcycline share this side effect. Because tetracyclines cross the placenta, a child may have tooth staining if the drugs are administered during the mother's pregnancy.
There are two types of TR. "Type 1" lesions are focal defects often caused by local inflammation. "Type 2" lesions are characterized by a generalized loss of root radiopacity on a dental radiograph. The definitive cause of type 2 TRs is unknown, but histologically destruction of the cementum and other mineralized tissue of the tooth root by odontoclasts is seen. It occurs secondary to the loss of the protective covering of the root (the periodontal ligaments) and possibly to a stimulus such as periodontal disease and the release of cytokines, leading to odontoclast migration. However, FORLs can develop in the absence of inflammation. The natural inhibition to root resorption provided by the lining of the root may be altered by increased amounts of Vitamin D, in cats supplied by their diet.
Dental plaque accumulates at the surfaces when proper cleaning and maintaining is not done. There is inflammation due to the bacteria released from the toxins. calculus forms and if not removed, causes this disease.
Preventive and restorative dental care is very important as well as considerations for esthetic issues since the crown are yellow from exposure of dentin due to enamel loss. The main objectives of treatment is pain relief, preserving patient's remaining dentition, and to treat and preserve the patient's occlusal vertical height.
Many factors are to be considered to decide on treatment options such as the classification and severity of AI, the patient's social history, clinical findings etc. There are many classifications of AI but the general management of this condition is similar.
Full-coverage crowns are sometimes being used to compensate for the abraded enamel in adults, tackling the sensitivity the patient experiences. Usually stainless steel crowns are used in children which may be replaced by porcelain once they reach adulthood. These aid with maintaining occlusal vertical dimension.
Aesthetics may be addressed via placement of composite or porcelain veneers, depending on patient factors eg age. If the patient has primary or mixed dentition, lab-made composite veneers may be provided temporarily, to be replaced by permanent porcelain veneers once the patient has stabilized permanent dentition. The patient's oral hygiene and diet should be controlled as well as they play a factor in the success of retaining future restorations.
In the worst-case scenario, the teeth may have to be extracted and implants or dentures are required. Loss of nerves in the affected teeth may occur.
AI can be classified according to their clinical appearances:
- Type 1 - Hypoplastic
Enamel of abnormal thickness due to malfunction in enamel matrix formation. Enamel is very thin but hard & translucent, and may have random pits & grooves. Condition is of autosomal dominant, autosomal recessive, or x-linked pattern. Enamel differs in appearance from dentine radiographically as normal functional enamel.
- Type 2 - Hypomaturation
Enamel has sound thickness, with a pitted appearance. It is less hard compared to normal enamel, and are prone to rapid wear, although not as intense as Type 3 AI. Condition is of autosomal dominant, autosomal recessive, or x-linked pattern. Enamel appears to be comparable to dentine in its radiodensity on radiograpshs.
- Type 3 - Hypocalcified
Enamel defect due to malfunction of enamel calcification, therefore enamel is of normal thickness but is extremely brittle, with an opaque/chalky presentation. Teeth are prone to staining and rapid wear, exposing dentine. Condition is of autosomal dominant and autosomal recessive pattern. Enamel appears less radioopaque compared to dentine on radiographs.
- Type 4: Hypomature hypoplastic enamel with taurodontism
Enamel has a variation in appearance, with mixed features from Type 1 and Type 2 AI. All Type 4 AI has taurodontism in common. Condition is of autosomal dominant pattern.
Other common features may include an anterior open bite, taurodontism, sensitivity of teeth.
Differential diagnosis would include dental fluorosis, molar-incisor hypomineralization, chronological disorders of tooth development.