NON SYNDROMIC FAMILIAL HYPODONTIA- A CASE SERIES years of age and hence no radiographic evaluation was conducted. 2.2. Case 2 AA was 10 years of age with an unremarkable medical history. The panoramic radiograph revealed oligodontia with teeth 13, 12 22, 23, 45, and 55 congenitally missing( Fig. 10). AA presented with a Class II malocclusion and a 7mm anterior overjet( Fig. 11, 12, 13). A similar short term and long term orthodontic plan was devised to correct the missing teeth, where in teeth 14 and 24 would be positioned in the place of the permanent canines and the space for the lateral incisors, 12 and 22, would be preserved for future implants, once the child turns 18 years of age. Teeth 75 and 85 would also be extracted and the space would be closed orthodontically.
2.3. Case 3 OA was 12 years of age with an unremarkable medical history and presented with tooth 45 congenitally missing and peg shaped upper lateral incisors( 12 and 22)( Fig. 14). The treatment plan included orthodontics to correct the crowding and retaining the space of tooth 45 for a future implant and reshaping the peg shaped maxillary lateral incisors. The timing of the diagnosis of hypodontia is important so as to choose an appropriate treatment plan which requires good patient and parent cooperation in order to achieve optimum long-term results.
3. Discussion Non-syndromic hypodontia is the most common form of congenitally missing teeth and can be familial or sporadic and usually occurs as an isolated trait. It can be inherited in an autosomal dominant, autosomal recessive or an X linked pattern. The etiology of congenitally missing teeth is reported to be a combination of genetic and environmental factors which can cause disturbances to the tooth germ during the initial formation stages [ 5,6 ]. The present cases represent a sporadic, non-syndromic familial form of hypodontia. There was no known history of any genetic syndromes in all three cases. Congenital missing teeth are defined as those that fail to erupt in the oral cavity and are not visible in radiographs. The diagnosis of tooth agenesis should be made after the 6 years of age excluding the third molar, and after 10 years if evaluating the third molar [ 13 ]. A panoramic radiograph is the best means to diagnose the number of missing teeth. Agenesis of the teeth in our case report was evident in the panoramic X rays and confirmed the diagnosis of hypodontia. The prevalence of hypodontia ranges from 1.6 % to 36.5 %, depending on the population studied. A 2014 systematic review found the overall global prevalence of hypodontia to be 6.4 %. Different continents displayed different prevalence values with Africa being the highest at 13.4 %, followed by Europe at 7 %, Asia and Australia both 6.3 %, North America 5 % and Latin America and the Caribbean displaying the lowest
Figure 14. Orthopantomogram, OA.
prevalence values at 4.4 %. Most individuals had only one or two teeth missing [ 3 ]. Mandibular second premolars are the most commonly affected and account for 29.9 % of all congenitally missing teeth, followed by maxillary lateral incisors( 24.3 %). Maxillary canines on the other hand made up only 2.5 % of all congenitally missing teeth [ 3 ]. Our case series showed three siblings with variable expressions of hypodontia. Case 1 and 2had congenitally missing maxillary canines in addition to maxillary lateral incisors. The occurrence of bilateral congenitally missing canines is very rare with prevalence rates reported to be as low as 0.14 % by Lombardo et al [ 14 ]. Hypodontia is often associated with other dental anomalies such as interdental spacing, microdontia, delayed tooth formation, over retained primary teeth, and reduced development of the alveolar bone and taurodontism [ 15 ]. Some studies however indicate that the agenesis of permanent teeth shows a strong correlation to the absence of the corresponding primary predecessors, while others indicate that the absence of a permanent successor causes a delay in the root resorption of the corresponding primary teeth [ 4,12 ]. Cases 1, 2 and 3 all showed interdental spacing and retained primary teeth where the permanent successors were congenitally missing. Additionally, Case 3 also showed microdontia in the form of maxillary peg shaped laterals. The treatment approach for hypodontia is specific to each case and is dependent on many factors such as the number of teeth missing, the condition and longevity of the primary predecessor, size and number of teeth remaining in both arches, the occlusal status, facial growth patterns, patient and parent preferences including the financial aspect of the treatment options offered [ 4,16,17 ]. A multidisciplinary approach is highly recommended which helps in the short and long-term treatment planning. The various specialists usually involved in the care of individuals with hypodontia include pediatric dentists, orthodontists, prosthodontists and oral surgeons. In the present cases, initial consultations were done with the orthodontist and prosthodontist. The treatment plan was discussed in detail with the parents and the patient preferences were also taken into consideration. In cases of hypodontia, the treatment options usually include the timely extraction of the over retained primary teeth that do not have a permanent successor to allow spontaneous orthodontic space closure with or without orthodontic alignment or placement of a prosthetic restoration to replace the missing tooth / teeth. In some cases, the primary tooth is retained to allow growth and impede resorption of the alveolar bone which will help
Case Report
Stomatology Edu Journal
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