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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.
Future studies will look further into the relationship of talon cusp and Rubinstein-Taybi syndrome and other oral-facial-digital syndromes. A former study showed a direct correlation in which 45 affected patients with Rubinstein-Taybi syndrome, 92% of these patients had talon cusp. Other researchers are attempting to trace talon cusp to ancestors and comparing dentition to modern humans. Another study done in 2007 examined the dentition of 301 Native American Indian skeletons for the presence or absence of talon cusp. The results showed five skeletons (2 percent) in the population had the trait.
In 2011, only 21 cases of talon cusp have been reported and are in literature. It appears that as of 2014 and 2015, additional research continues in hopes of finding the cause and mechanism of talon cusp. With the majority of cases of talon cusp being unreported, it remains difficult to conduct tests, come up with conclusions, conduct surgery and perform research with small numbers.
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.
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.
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.
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.
A child with posterior crossbite should be treated immediately if the child shifts his mandible on closing which is often seen in a unilateral crossbite as mentioned above. The best age to treat a child with crossbite is in their mixed dentition when their palatal sutures have not fused to each other. Palatal expansion allows more space in an arch to relieve crowding and correct posterior crossbite. The correction can include any type of palatal expanders that will expand the palate which resolves the narrow constriction of the maxilla. There are several therapies that can be used to correct a posterior crossbite: braces, 'Z' spring or cantilever spring, quad helix, removable plates, clear aligner therapy, or a Delaire mask. The correct therapy should be decided by the orthodontist depending on the type and severity of the crossbite.
One of the keys in diagnosing the anterior crossbite due to skeletal vs dental causes is diagnosing a CR-CO shift in a patient. An adolescent presenting with anterior crossbite may be positioning their mandible forward into centric occlusion (CO) due to the dental interferences. Thus finding their occlusion in centric relation (CR) is key in diagnosis. For anterior crossbite, if their CO matches their CR then the patient truly has a skeletal component to their crossbite. If the CR shows a less severe class 3 malocclusion or teeth not in anterior crossbite, this may mean that their anterior crossbite results due to dental interferences.
Goal to treat unilateral crossbites should definitely include removal of occlusal interferences and elimination of the functional shift. Treating posterior crossbites early may help prevent the occurrence of Temporomandibular joint pathology.
Unilateral crossbites can also be diagnosed and treated properly by using a Deprogramming splint. This splint has flat occlusal surface which causes the muscles to deprogram themselves and establish new sensory engrams. When the splint is removed, a proper centric relation bite can be diagnosed from the bite.
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.
Before root canal treatment or extraction are carried out, the clinician should have thorough knowledge about the root canal morphology to avoid complications.
One of the biggest risks factors faced by the affected foals is susceptibility to secondary infection. Within three to eight days after birth, the foal may die from infection or is euthanized for welfare reasons.
Literature states that very few crossbites tend to self-correct which often justify the treatment approach of correcting these bites as early as possible. Only 0–9% of crossbites self-correct. Lindner et al. reported that in a 50% of crossbites were corrected in 76 four year old children.
Unerupted microdonts may require surgical removal to prevent the formation of cysts. Erupted microdonts, peg laterals especially, may cause cosmetic concern. Such teeth may be restored to resemble normal sized teeth, typically with composite build ups or crowns. Orthodontics may be required in severe cases to close gaps between the teeth.
In disease states, maxillary prognathism is associated with Cornelia de Lange syndrome; however, so-called false maxillary prognathism, or more accurately, retrognathism, where there is a lack of growth of the mandible, is by far a more common condition.
Prognathism, if not extremely severe, can be treated in growing patients with orthodontic functional or orthopaedic appliances. In adult patients this condition can be corrected by means of a combined surgical/orthodontic treatment, where most of the time a mandibular advancement is performed. The same can be said for mandibular prognathism.
Females are affected more than males, and the condition occurs in permanent (adult) teeth more than deciduous (baby teeth or milk teeth).
Biopsies of the skin may be performed to identify the cleavage that takes place at the dermal-epidermal junction. Another test that can aid in a diagnosis of JEB is the positive Nikolsky’s sign. By applying pressure to the skin, transverse movements can indicate slipping between the dermal and epidermal layers. An easier and more definitive test is through polymerase chain reaction (PCR). This method allows mane and tail samples to be genetically tested for the mutated genes that cause the condition. Hair samples must be pulled, not cut, with roots attached. The test can detect both JEB1 and JEB2. Testing costs around $35.00 US per sample.
Man-Suk Baek and others evaluated long-term stability of anterior open bite by intrusion of maxillary posterior teeth. Their results showed that the molars were intruded by 2.39mm during treatment and relapsed back by 0.45mm or 22.8%. The incisal overbite increased by 5.56mm during treatment and relapsed back by 1.20mm or 17%. They concluded that majority of the relapse occurred during first year of treatment.
Geoffrey Greenlee and others published a meta-analysis in 2011 which concluded that patients with orthognathic surgical correction of open bite had 82% stability in comparison to non-surgical correction of open bite which had 75% of stability after 1or more year of treatment. Both the groups started with 2-3mm of open bite initially.
The most common treatment for mandibular prognathism is a combination of orthodontics and orthognathic surgery. The orthodontics can involve braces, removal of teeth, or a mouthguard.
The surgery required has led, in some cases, to identity crises in patients, whereby the new facial structure has a negative impact mentally on how the patients perceive themselves.
Prosthetic replacement of missing teeth is possible using dental implant technology or dentures. This treatment can be successful in giving patients with anodontia a more aesthetically pleasing appearance. The use of an implant prosthesis in the lower jaw could be recommended for younger patients as it is shown to significantly improve the craniofacial growth, social development and self-image. The study associated with this evidence worked with individuals who had ectodermal dysplasia of varying age groups of up to 11, 11 to 18 and more than 18 years. It was noted that the risk of implant failure was significantly higher in patients younger than 18 years, but there is significant reason to use this methodology of treatment in those older. Overall the use of an implant-prosthesis has a considerable functional, aesthetic and psychological advantage when compared to a conventional denture, in the patients.
Nasopalatine duct cysts usually present as asymptomatic palatal swellings, but they may rarely be accompanied by pain and/or purulent discharge. The cysts are generally treated by .
Pre-formed metal crowns (PMC), also known as stainless steel crowns, can be used to reduce the risk of marginal breakdown, coronal leakage and has a good longevity. The use of preformed metal crowns on MIH-affected molars can prevent further tooth loss, control hypersensitivity and aim to establish correct interproximal and occlusal contact. They are relatively inexpensive and require little preparation.
To prevent further tooth preparation and tissue loss, use of the Hall Technique should also be considered. There advantage is use during any stage of post-eruptive breakdown, but evidence of their efficacy is limited. Although the PMC has evidence to show that it is well accepted, a few of the children and their carers expressed their concerns about the metallic appearances of the restoration.
Crowding of the teeth is treated with orthodontics, often with tooth extraction, clear aligners, or dental braces, followed by growth modification in children or jaw surgery (orthognathic surgery) in adults. Surgery may be required on rare occasions. This may include surgical reshaping to lengthen or shorten the jaw (orthognathic surgery). Wires, plates, or screws may be used to secure the jaw bone, in a manner similar to the surgical stabilization of jaw fractures. Very few people have "perfect" alignment of their teeth. However, most problems are very minor and do not require treatment.
The presence of a supernumerary tooth, particularly when seen in young children, is associated with a disturbance of the maxillary incisor region. This commonly results in the impaction of the incisors during the mixed dentition stage. The study debating this also considered many other factors such as: the patient’s age, number, morphology, growth orientation and position of the supernumerary tooth. Therefore, the presence of a supernumerary tooth when found must be appropriately approached with the correct treatment plan incorporating the likelihood of incisal crowding.
Natal teeth are teeth that are present above the gumline (have already erupted) at birth, and neonatal teeth are teeth that emerge through the gingiva during the first month of life (the neonatal period).
The incidence of neonatal teeth varies considerably, between 1:700 and 1:30,000 depending on the type of study; the highest prevalence is found in the only study that relies on personal examination of patients.
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.