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In the 1960s and 1970s, several studies were conducted sponsored by the U.S. Atomic Energy Commission, with the aim of finding a link between genetics and hypodontia.
MIH examination should be carried out on clean, wet teeth. The ideal age for examination is when the child is 8 years old - the age where all permanent first molars and most of the incisors are erupted. The permanent first molar will also still be in a comparatively sound condition without excessive post-eruption breakdown. Judgements of each individual teeth should be recorded, aiding the correct diagnosis of the condition.
There is currently a lack of standardisation in the scoring system and severity indices used to record the diagnosis of MIH. Various systems commonly employed in studies include:
- Modified Defect of Dental Enamel (DDE) Index: This set of criteria allows for enamel defects to be detected, enabling a distinction between demarcated and diffused opacities.
- European Academy of Paediatric Dentistry (EAPD) judgement criteria: This set of criteria was developed in 2003 to standardise classifications for use in epidemiological studies. However, while it allows the categorisation of the enamel condition, it does not address the severity of the enamel condition.
- Molar Hypomineralisation Severity Index (MHSI): This set of criteria has been developed to address deficiencies in indices concerning the severity of hypomineralisation. It is based on both the clinical characteristics of hypomineralised defects and the EAPD judgement criteria.
It is phenotypically difficult to diagnose between TDO and Amelogenesis imperfecta of the hypomaturation-hypoplasia type with taurodontism (AIHHT) as they are very closely linked phenotypically during adulthood, and the only distinguishing characteristic is found during genetic analysis by Polymerase Chain Reaction (PCR) amplification. This type of test in diagnosis of TDO is only used during research or if there is a concern of genetic issue to a particular individual whose family member has been diagnosed with TDO.
The Kennedy classification quantifies partial edentulism. An outline is covered at the removable partial denture article.
TDO is a genetic based disorder it is diagnosed based on radiographic imaging, physical characteristics of the disease, and genetic testing if necessary. PCR amplification is used to check for normal and deletion allele, found in the 141 base pair allele. A four base pair deletion in exon 3 is also noted in patients with TDO; deletion in two transcription factor genes DLX-3 and DLX-7 gene (distal-less gene) that occurs by a frameshift mutation, makes this gene shorter than its normal length and non-functional. Radiographs such as cephalometric analysis or panoramic radiograph are used to detect skeletal abnormalities in TDO cases; these radiographs along with the phenotypic effects of the disease are often enough evidence for proper diagnosis. In TDO, radiologic imaging almost always shows evidence of hardening of bone tissue (sclerosis), lesions on the bone structures surrounding the teeth due to decay or trauma, or hard tissue mass. The radiographic testing is non-invasive, and involves the patient to be able to sit or stand in front of the radiographic device with their mouth closed and lips relaxed for approximately one minute. Oral abnormalities are diagnosed by a visual dental examination. A normal oral evaluation would show no signs of broken or fractured teeth, attrition of tooth enamel, no spacing between teeth, no soft tissue mass or sign of dental abscess, and a bite relationship where the mandibular (bottom) teeth interdigitate within a normal plane of 1-2mm behind and underneath the maxillary (top) teeth.
It is difficult to diagnose clinically. Radiographs taken at different angles can aid detection of concrescence. Histological examination for extracted teeth could confirm diagnosis.
The diagnosis of impaction can be made clinically if enough of the wisdom tooth is visible to determine its angulation, depth, and if the patient is old enough that further eruption or uprighting is unlikely. Wisdom teeth continue to move into adulthood (20–30 years old) due to eruption and then continue some later movement owing to periodontal disease.
If the tooth cannot be assessed with clinical exam alone, the diagnosis is made using either a panoramic radiograph or cone-beam CT. Where unerupted wisdom teeth still have eruption potential several predictors are used to determine the chance of the teeth becoming impacted. The ratio of space between the tooth crown length and the amount of space available, the angle of the teeth compared to the other teeth are the two most commonly used predictors, with the space ratio being the most accurate. Despite the capacity for movement into early adulthood, the likelihood that the tooth will become impacted can be predicted when the ratio of space available to the length of the crown of the tooth is under 1.
There is no standard to screen for wisdom teeth. It has been suggested, absent evidence to support routinely retaining or removing wisdom teeth, that evaluation with panoramic radiograph, starting between the ages of 16 and 25 be completed every 3 years. Once there is the possibility of the teeth developing disease, then a discussion about the operative risks versus long-term risk of retention with an oral and maxillofacial surgeon or other clinician trained to evaluate wisdom teeth is recommended. These recommendations are based on expert opinion level evidence. Screening at a younger age may be required if the second molars (the "12-year molars") fail to erupt as ectopic positioning of the wisdom teeth can prevent their eruption. Radiographs can be avoided if the majority of the tooth is visible in the mouth.
If the condition is not affecting patient, no treatment is needed. Concrescence teeth could be reshaped and replaced with full crowns. However, if the teeth are having recurrent problems, non-restorable or pain, extraction should be considered.
Although these teeth are usually asymptomatic and pose no threat to the individual, they are often extracted for aesthetic reasons. This is done particularly if the mesiodens is positioned in the maxillary central incisor region. The traditional method of removal is done by using bone chisels, although a more advanced technique has been found to be more beneficial, especially if surgery is required . Through the use of Piezoelectricity, Piezoelectric ultrasonic bone surgery may be more time consuming than the traditional method but it seems to reduce the post-operative bleeding and associated complications quite significantly.
The oral rehabilitation of hypodontia, especially where a significant number of teeth have not developed, is often a multidisciplinary process, involving a specialist orthodontist, a consultant in restorative dentistry, and a paediatric dentist in the earlier years. The process of treating and managing hypodontia begins in the early years of the patient's dentition where absent teeth are identified and the process of maintaining the remaining teeth begins. This is largely conducted by the paediatric dentist with orthodontic input. Once all the adult teeth have erupted the orthodontist is likely to liaise with the restorative dentist regarding optimal positioning of teeth for subsequent replacement with prosthodontic methods. This may include the utilisation of a resin-retained bridge and implants for spaces or composite resin, veneers or crowns where teeth are diminutive or misshaped.
To manage the condition, it is important to first diagnose it, describing the type of tooth surface loss, its severity and location. Early diagnosis is essential to ensure tooth wear has not progressed past the point of restoration. A thorough examination is required, because it might give explanation to the aetiology of the TSL.
The examination should include assessment of:
- Temporomandibular joint function and associated musculature
- Orthodontic examination
- Intra oral soft tissue analysis
- Hard tissue analysis
- Location and severity of tooth wear
- Social history, particularly diet
It is important to record severity of tooth wear for monitoring purposes, helping to differentiate between pathological and physiological tooth surface loss. It is essential to determine whether the tooth wear is ongoing or has stabilized. However where generalised, the underlying cause can be assumed to be bruxism. In fast-progressing cases, there is commonly a coexisting erosive diet contributing to tooth surface loss.
Before root canal treatment or extraction are carried out, the clinician should have thorough knowledge about the root canal morphology to avoid complications.
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.
No intervention is usually recommended unless they are causing difficulty to the infant or mother.
However some recommend that they be removed as the tooth can cut or amputate the tip of the tongue.
They should be left in the mouth as long as possible to decrease the likelihood of removing permanent tooth buds with the natal tooth. They should also not be removed if the infant has hypoprothrombinemia. In case of complications when the natal teeth need to be removed, dental radiographs should be obtained whenever possible, and evaluated and followed up with pediatric dentists.
Cast restorations may include full coverage crowns for MIH-affected permanent teeth. Generally cast restorations requiring tooth preparation are not recommended in young children due to large pulp size, short crown height and potential difficulties in obtaining a good impression for subgingival crown margins.
Management of teeth with PFE can include extractions of affected teeth, followed by orthodontic space closure or placement of a prosthetic implant with a bone graft. This option can only be applied to a single tooth that is affected. If multiple teeth are affected then, a segmental osteotomy may be performed to bring the entire segment into occlusion. However, minimal success has been shown following this procedure. These teeth usually are "non-responsive" to the orthodontic force and studies have shown that ankylosis of these teeth can occur if force applied.
All impacted teeth, unless otherwise contraindicated, are considered for surgical removal. Thus, dental extractions will often take place. The type of extraction (simple or surgical) often depends on the location of the teeth.
In some cases, for aesthetic purposes, a surgeon may wish to expose the canine. This may be achieved through open or closed exposure. Studies show no advantage of one method over another.
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).
Most commonly the individual complains of food getting lodged beneath the gums and a soreness that is usually confused with throat infections. In slightly milder forms a swelling is visible and mouth opening becomes difficult in severe cases. Pain is invariably present.
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.
When a diagnosis of bruxism has been confirmed, it is recommended that the patient buy a full-coverage acrylic occlusal splint, such as a Michigan Splint or Tanner appliance, to prevent further bruxism. Patients must be monitored closely, with clinical photographs 6–12 monthly to evaluate if the tooth surface loss is being prevented.
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.
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).
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.