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.

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.

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.

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.

Studies have shown that sinusitis is found in about 60% of the cases on the fourth day after the manifestation of sinus. Moreover, patient may be afflicted with an acute sinus disease if OAC is not treated promptly upon detecting clear signs of sinusitis. So, early diagnosis of OAC must be conducted in order to prevent OAF from setting in.

Spontaneous healing of small perforation is expected to begin about 48 hours after tooth extraction and it remains possible during the following two weeks. Patient must consult the dentist as early as possible should a large defect of more than 7mm in diameter or a dogged opening that requires closure is discovered so that appropriate and suitable treatment can be swiftly arranged or referral to Oral Maxillofacial Surgery (OMFS) be made at the local hospital, if required.

A comprehensive preoperative radiographic evaluation is a must as the risk of OAC can increase due to one or more of the following situations :-

- Close relationship between the roots of the maxillary posterior teeth and the sinus floor

- Increased divergence or dilaceration of the roots of the tooth

- Marked pneumatization of the sinus leading to a larger size

- Peri-radicular lesions involving teeth or roots in close association with the sinus floor

Hence, in such cases:

- Avoid using too much of apical pressure during tooth extraction

- Perform surgical extraction with roots sectioning

- Consider referral to OMFS at local hospital

A non-vital tooth is necessary for the diagnosis of a periapical cyst, meaning the nerve has been removed by root canal therapy. Oral examination of the surrounding intraoral anatomical structures should be palpated to identify the presence of bone expansion or displacement of tooth roots as well as crepitus noises during examination, indicating extensive bone damage. Bulging of the buccal or lingual cortical plates may be present. Age of occurrence in the patient, the location of the cyst, the edges of cystic contours, and the impact that the cyst has on adjacent structures must all be considered for proper diagnosis.

Several lesions can appear similarly in radiographic appearance. Intraoral X-rays or a 3-D cone beam scan of the affected area can be used to obtain radiological images and confirm diagnosis of cysts in the periapical area. Circular or ovoid radiolucency surrounding the root tip of approximately 1-1.5 cm in diameter is indicative of the presence of a periapical cyst. The border of the cyst is seen as a narrow opaque margin contiguous with the lamina dura. In cysts that are actively enlarging, peripheral areas of the margin may not be present. Periapical cysts have a characteristic unilocular shape on radiographs. There is also a severe border of cortication between the cyst and surrounding bone. Pseudocysts, on the other hand, have a fluid filled cavity but are not lined by epithelium, therefore they have a less severe and more blurred border between the fluid and bony surroundings.

Resorption of the roots of affected teeth may also be observed as the absence of portions of normal root structures.

Infected cysts will produce a positive percussion test on the affected tooth as well as a negative response to the pulp test. There may also be visible swelling in the overlying soft tissues. The affected tooth may also exhibit discoloration.

A periodontal abscess may be difficult to distinguish from a periapical abscess. Indeed, sometimes they can occur together. Since the management of a periodontal abscess is different from that of a periapical abscess, this differentiation is important to make.

- If the swelling is over the area of the root apex, it is more likely to be a periapical abscess; if it is closer to the gingival margin, it is more likely to be a periodontal abscess.

- Similarly, in a periodontal abscess pus most likely discharges via the periodontal pocket, whereas a periapical abscess generally drains via a parulis nearer to the apex of the involved tooth.

- If the tooth has pre-existing periodontal disease, with pockets and loss of alveolar bone height, it is more likely to be a periodontal abscess; whereas if the tooth has relatively healthy periodontal condition, it is more likely to be a periapical abscess.

- In periodontal abscesses, the swelling usually precedes the pain, and in periapical abscesses, the pain usually precedes the swelling.

- A history of toothache with sensitivity to hot and cold suggests previous pulpitis, and indicates that a periapical abscess is more likely.

- If the tooth which gives normal results on pulp sensibility testing, is free of dental caries and has no large restorations; it is more likely to be a periodontal abscess.

- A dental radiograph is of little help in the early stages of a dental abscess, but later usually the position of the abscess, and hence indication of endodontal/periodontal etiology can be determined. If there is a sinus, a gutta percha point is sometimes inserted before the x-ray in the hope that it will point to the origin of the infection.

- Generally, periodontal abscesses will be more tender to lateral percussion than to vertical, and periapical abscesses will be more tender to apical percussion.

Since most toothache is the result of plaque-related diseases, such as tooth decay and periodontal disease, the majority of cases could be prevented by avoidance of a cariogenic diet and maintenance of good oral hygiene. That is, reduction in the number times that refined sugars are consumed per day and brushing the teeth twice a day with fluoride toothpaste and flossing. Regular visits to a dentist also increases the likelihood that problems are detected early and averted before toothache occurs. Dental trauma could also be significantly reduced by routine use of mouthguards in contact sports.

Successful treatment of a dental abscess centers on the reduction and elimination of the offending organisms.

This can include treatment with antibiotics and drainage. If the tooth can be restored, root canal therapy can be performed. Non-restorable teeth must be extracted, followed by curettage of all apical soft tissue.

Unless they are symptomatic, teeth treated with root canal therapy should be evaluated at 1- and 2-year intervals after the root canal therapy to rule out possible lesional enlargement and to ensure appropriate healing.

Abscesses may fail to heal for several reasons:

- Cyst formation

- Inadequate root canal therapy

- Vertical root fractures

- Foreign material in the lesion

- Associated periodontal disease

- Penetration of the maxillary sinus

Following conventional, adequate root canal therapy, abscesses that do not heal or enlarge are often treated with surgery and filling the root tips; and will require a biopsy to evaluate the diagnosis.

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.

Based on the optical changes induced in eroded tissue by the lesions, in 2015 Koshoji "et al." also demonstrated in a novel method that using laser speckle images (LSI) it is possible to acquire information on the microstructure of the enamel and detect minimal changes, such as early non-carious lesions. To produce the erosion, the samples were divided into four groups and immersed in 30 ml of a cola-based beverage (pH approximately 2.5) at room temperature. A representative image of the samples under white and laser illumination shows that although there are visible stains in the left portion of each sample due the dye from the cola beverage, structural changes are difficult to assess with the naked eye.

To differentiate the sound and eroded tissues, contrast analysis was performed of the speckle patterns in the images. Since this analysis is, in its essence, the ratio of the standard deviation and average intensity, the LASCA map of the lesion is generally higher than in sound tissue. This phenomenon is demonstrated in the LASCA maps which show the greater prevalence of dark blue on the right side, indicating sound tissue, and lower prevalence on the left side, indicating eroded tissue. The contrast ratio of the LASCA maps demonstrates that laser speckle images are sensitive to even small changes in the microstructure of the surface.

Erosion is highly prevalent in people of all ages. However, an objective diagnostic procedure is still needed, thus the study of the laser speckle imaging for tooth enamel may provide the first low cost objective diagnostic method for this disease. The analysis of laser speckle imaging in the spatial domain is a powerful diagnostic technique that provides information on the surface microstructure of tooth enamel after an acid etching procedure using patterns and LASCA maps. In an erosion model, these patterns are associated with mineral loss from the enamel. This method has proven sensitive to 10 minutes of acid etching on tooth enamel, which is a lesion so incipient that is not likely to be detected in clinical practice even by a trained dentist, besides it is also sensitive to the erosion progression.

The presentation of caries is highly variable. However, the risk factors and stages of development are similar. Initially, it may appear as a small chalky area (smooth surface caries), which may eventually develop into a large cavitation. Sometimes caries may be directly visible. However other methods of detection such as X-rays are used for less visible areas of teeth and to judge the extent of destruction. Lasers for detecting caries allow detection without ionizing radiation and are now used for detection of interproximal decay (between the teeth). Disclosing solutions are also used during tooth restoration to minimize the chance of recurrence.

Primary diagnosis involves inspection of all visible tooth surfaces using a good light source, dental mirror and explorer. Dental radiographs (X-rays) may show dental caries before it is otherwise visible, in particular caries between the teeth. Large areas of dental caries are often apparent to the naked eye, but smaller lesions can be difficult to identify. Visual and tactile inspection along with radiographs are employed frequently among dentists, in particular to diagnose pit and fissure caries. Early, uncavitated caries is often diagnosed by blowing air across the suspect surface, which removes moisture and changes the optical properties of the unmineralized enamel.

Some dental researchers have cautioned against the use of dental explorers to find caries, in particular sharp ended explorers. In cases where a small area of tooth has begun demineralizing but has not yet cavitated, the pressure from the dental explorer could cause a cavity. Since the carious process is reversible before a cavity is present, it may be possible to arrest caries with fluoride and remineralize the tooth surface. When a cavity is present, a restoration will be needed to replace the lost tooth structure.

At times, pit and fissure caries may be difficult to detect. Bacteria can penetrate the enamel to reach dentin, but then the outer surface may remineralize, especially if fluoride is present. These caries, sometimes referred to as "hidden caries", will still be visible on X-ray radiographs, but visual examination of the tooth would show the enamel intact or minimally perforated.

The differential diagnosis for dental caries includes dental fluorosis and developmental defects of the tooth including hypomineralization of the tooth and hypoplasia of the tooth.

The early carious lesion is characterized by demineralization of the tooth surface, altering the tooth's optical properties. Technology utilizing laser speckle image (LSI) techniques may provide a diagnostic aid to detect early carious lesions.

The primary aim of treatment of a newly formed oroantral communication is to prevent the development of an oroantral fistula as well as chronic sinusitis. The decision on how to treat OAC/OAF depends on various factors. Small size communications between 1 and 2 mm in diameter, if uninfected, are likely to form a clot and heal by itself later. Communications larger than this require treatments to close the defect and these interventions can be categorised into 3 types: surgical, non-surgical and pharmacological.

Personal hygiene care consists of proper brushing and flossing daily. The purpose of oral hygiene is to minimize any etiologic agents of disease in the mouth. The primary focus of brushing and flossing is to remove and prevent the formation of plaque or dental biofilm. Plaque consists mostly of bacteria. As the amount of bacterial plaque increases, the tooth is more vulnerable to dental caries when carbohydrates in the food are left on teeth after every meal or snack. A toothbrush can be used to remove plaque on accessible surfaces, but not between teeth or inside pits and fissures on chewing surfaces. When used correctly, dental floss removes plaque from areas that could otherwise develop proximal caries but only if the depth of sulcus has not been compromised. Other adjunct oral hygiene aids include interdental brushes, water picks, and mouthwashes.

However oral hygiene is probably more effective at preventing gum disease (periodontal disease) than tooth decay. Food is forced inside pits and fissures under chewing pressure, leading to carbohydrate-fueled acid demineralisation where the brush, fluoride toothpaste, and saliva have no access to remove trapped food, neutralise acid, or remineralise demineralised tooth like on other more accessible tooth surfaces. (Occlusal caries accounts for between 80 and 90% of caries in children (Weintraub, 2001).) Higher concentrations of fluoride (>1,000 ppm) in toothpaste also helps prevents tooth decay, with the effect increasing with concentration. Chewing fibre like celery after eating forces saliva inside trapped food to dilute any carbohydrate like sugar, neutralise acid and remineralise demineralised tooth. The teeth at highest risk for carious lesions are the permanent first and second molars due to length of time in oral cavity and presence of complex surface anatomy.

Professional hygiene care consists of regular dental examinations and professional prophylaxis (cleaning). Sometimes, complete plaque removal is difficult, and a dentist or dental hygienist may be needed. Along with oral hygiene, radiographs may be taken at dental visits to detect possible dental caries development in high-risk areas of the mouth (e.g. "bitewing" X-rays which visualize the crowns of the back teeth).

The best method of maintaining the health of teeth is to practice exemplary oral hygiene. More tooth loss is likely to occur if intervention takes place. However, factors such as present complaint, patient age, severity of the problem, can affect the treatment plan or options.

Stainless steel crowns which also known as "hall crowns" can prevent tooth wear and maintain occlusal dimension in affected primary teeth. However, if demanded, composite facings or composite strip crowns can be added for aesthetic reasons.

Intraoral dental sinus (also termed a parulis and commonly, a gumboil) is an oral lesion characterized by a soft erythematous papule (red spot) that develops on the alveolar process in association with a non-vital tooth and accompanying dental abscess. A parulis is made up of inflamed granulation tissue.

Less commonly, dental infections drain onto the surface of the skin, forming a cutaneous sinus of dental origin.

This condition is often resolved by endodontic treatment and does not have indication for antibiotic use. This is a common mistake among health professionals.

Preventive and management strategies include the following:

- Avoid sweet and acid foods. Even low sugar contained in fruit is bad for the teeth since it is the sugar/acid exposure time which erodes the teeth, not the amount of sugar.

- Modifying the pH of the food or beverage contributing to the problem, or changing lifestyle to avoid the food or beverage.

- Rinsing immediately after drinking or eating.

- Drinking through a straw

- Avoid abrasive forces. Use a soft bristled toothbrush and brush gently. Avoid brushing immediately after consuming acidic food and drink as teeth will be softened. Leave at least half an hour of time in between. Rinsing with water is better than brushing after consuming acidic foods and drinks.

- Using a remineralizing agent, such as sodium fluoride solution in the form of a fluoride mouthrinse, tablet, or lozenge, immediately before brushing teeth.

- Applying fluoride gels or varnishes to the teeth.

- Drinking milk or using other dairy products.

- Dentine bonding agents applied to areas of exposed dentin

- Use a neutralizing agent such as antacid tablets only as a last-resort. They have negative long-run effects.

- Treating the underlying medical disorder or disease.

The infected tissue of the periapical cyst must be entirely removed, including the epithelium of the cyst wall; otherwise a relapse is likely to occur. Root canal treatment should be performed on the tooth if it is determined that previous therapy was unsuccessful. Removal of the necrotic pulp and the inflamed tissue as well as proper sealing of the canals and an appropriately fitting crown will allow the tooth to heal under uninfected conditions.

Surgical options for previously treated teeth that would not benefit from root canal therapy include cystectomy and cystostomy. This route of treatment is recommended upon discovery of the cyst after inadequate root canal treatment. A cystectomy is the removal of a cyst followed by mucosa and wound closure to reduce chances of cyst regeneration. This type of treatment is more ideal for small cysts.

A cystostomy is recommended for larger cysts that compromise important adjacent anatomy. The cyst is tamponaded to allow for the cyst contents to escape the bone. Over time, the cyst decreases in size and bone regenerates in the cavity space.

Marsupialization could also be performed, which involves suturing the edges of the gingiva surrounding the cyst to remain open. The cyst then drains its contents and heal without being prematurely closed. The end result is the same as the cystostomy, bone regeneration. For both a cystostomy and marsupialization, root resectioning may also be required in cases where root resorption has occurred.

A cutaneous sinus of dental origin is where a dental infection drains onto the surface of the skin of the face or neck. This is uncommon as usually dental infections drain into the mouth, typically forming a parulis ("gumboil").

Cutaneous sinuses of dental origin tend to occur under the chin or mandible. Without elimination of the source of the infection, the lesion tends to have a relapsing and remitting course, with healing periods and periods of purulent discharge.

Cutaneous sinus tracts may result in fibrosis and scarring whcich may cause cosmetic concern. Sometimes minor surgery is carried out to remove the residual lesion.

Treatment is only required if the occlusion or bite of the person is compromised and causing other dental problems. Multiple long-term clinical problems can arise such as occlusal interferences, aesthetic disturbances, loss of pulp vitality, irritation of tongue during mastication and speech, caries and displacement of the affected tooth. Most people with talon cusp will live their normal lives unless the case is severe and causes a cascade of other dental issues that lead to additional health problems. This dental anomaly would not be considered fatal. Generally talon cusps on lower teeth require no treatment, but talon cusps on upper teeth may interfere with the bite mechanics and may need to be removed or reduced.

Small talon cusps that produce no symptoms or complication for a person can remain untreated. However large talon cusps should not.

Some common treatments include:

- Fissure sealing

- Composite resin restoration

- Reduction of cusp

- Pulpotomy

- Root canal (endodontic treatment)

- Extraction

The condition is usually benign, but it can cause mild irritation to soft tissues around the teeth and the tongue, and if large enough, may pose an aesthetic problem. Talon cusps that are too large are filed down with a motorized file, and then endodontic therapy is administered.

In order to prevent any future dental complications, when talon cusp is present due to an early diagnosis it would be best to see a dentist regularly every six months for routine dental checkups, remain under observation, brush and floss properly and undergo regular topical applications of fluoride gel to prevent caries and to promote enamel strength.

Sometimes, pressure changes damage teeth (rather than just causing pain). When the external pressure rises or falls and the trapped air within the void cannot expand or contract to balance the external pressure, the pressure difference on the rigid structure of the tooth can occasionally induce stresses sufficient to fracture the tooth or dislodge a filling. Typically this is seen in underwater divers or aviators who experience pressure changes in the course of their activity. Identifying the pain during a pressure change is a diagnostic indicator for the clinician. Treatment involves removing the void space by carefully replacing the offending restoration, repeating the endodontic treatment or removing the tooth.

The Fédération dentaire internationale describes 4 classes of barodontalgia. The classes are based on signs and symptoms. They also provide specific and valuable recommendations for therapeutic intervention.

Odontomas are thought to be the second most frequent type of odontogenic tumor worldwide (after ameloblastoma), accounting for about 20% of all cases within this relatively uncommon tumor category which shows large geographic variations in incidence.

Most cysts are discovered as a chance finding on routine dental radiography. On an x-ray, cysts appear as radiolucent (dark) areas with radiopaque (white) borders. Cysts are usually unilocular, but may also be multilocular. Sometimes aspiration is used to aid diagnosis of a cystic lesion, e.g. fluid aspirate from a radicular cyst may appear straw colored and display shimmering due to cholesterol content. Almost always, the cyst lining is sent to a pathologist for histopathologic examination after it has been surgically removed. This means that the exact diagnosis of the type of cyst is often made in retrospect.