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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.
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.
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.
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.
It is difficult to diagnose clinically. Radiographs taken at different angles can aid detection of concrescence. Histological examination for extracted teeth could confirm diagnosis.
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.
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.
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.
The Kennedy classification quantifies partial edentulism. An outline is covered at the removable partial denture article.
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.
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.
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.
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.
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.
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.
Preventive and restorative care are important as well as esthetics as a consideration. This ensures preservation of the patient's vertical face height between their upper and lower teeth when they bite together. The basis of treatment is standard throughout the different types of DI where prevention, preservation of occlusal face height, maintenance of function, and aesthetic needs are priority. Preventive efforts can limit pathology occurring within the pulp, which may render future endodontic procedures less challenging, with better outcomes.
- Challenges are associated with root canal treatment of teeth affected by DI due to pulp chamber and root canal obliteration, or narrowing of such spaces.
- If root canal treatment is indicated, it should be done in a similar way like with any other tooth. Further consideration is given for restoring the root-treated tooth as it has weaker dentine which may not withstand the restoration.
Preservation of occlusal face height may be tackled by use of stainless steel crowns which are advocated for primary teeth where occlusal face height may be hugely compromised due to loss of tooth tissue as a result of attrition, erosion of enamel.
In most cases, full-coverage crowns or veneers (composite/porcelain) are needed for aesthetic appearance, as well as to prevent further attrition. Another treatment option is bonding, putting lighter enamel on the weakened enamel of the teeth and with lots of treatments of this bonding, the teeth appear whiter to the eye, but the teeth on the inside and under that cover are still the same. Due to the weakened condition of the teeth, many common cosmetic procedures such as braces and bridges are inappropriate for patients with Dentinogenesis imperfecta and are likely to cause even more damage than the situation they were intended to correct.
Dental whitening (bleaching) is contraindicated although it has been reported to lighten the color of DI teeth with some success; however, because the discoloration is caused primarily by the underlying yellow-brown dentin, this alone is unlikely to produce normal appearance in cases of significant discoloration.
If there is considerable attrition, overdentures may be prescribed to prevent further attrition of remaining teeth and for preserving the occlusal face height.
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.
Before root canal treatment or extraction are carried out, the clinician should have thorough knowledge about the root canal morphology to avoid complications.
Bisphosphonates have recently been introduced to treat several bone disorders, which include osteogenesis imperfecta.
A recognized risk of this drug relevant to dental treatments is bisphosphonate-associated osteonecrosis of the jaw (BRONJ). Occurrences of this risk is associated with dental surgical procedures such as extractions.
Dental professionals should therefore proceed with caution when carrying out any dental procedures in patients who have Type 2 DI who may be on bisphosphonate drug therapy.
Treatment and prognosis are usually based upon keeping these teeth and preserving the alveolus. For erupted teeth, endodontics is an option if the tooth is devitalized and restorable. For unerupted teeth, function can be restored with a removable partial denture until all major growth has been completed and a final restoration can be placed.
Prevention is of prior importance at an early developmental age as the defective tooth is more likely to have caries and post-eruptive breakdown due to its increased porosity. Appropriate dietary advice and toothpaste with a fluoride level of at least 1,000 ppm F should be recommended. For treating spontaneous hypersensitivity professional applications of fluoride varnish (e.g. Duraphat 22,600ppm F) or 0.4% stannous fluoride gel may be helpful.
Casein Phosphopepetide-Amorphus Calcium Phosphate (CPP-ACP) provides a supersaturated environment of calcium and phosphate on the enamel surface to enhance remineralisation in the form of toothpaste or sugar free chewing gum. Its clinical effectiveness is still debatable but may benefit those patients who complain of mild pain to external stimuli.
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.
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.
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).
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.