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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