Effects of hypodontia on craniofacial structures and mandibular growth pattern

Abstract

IntroductionThis study was performed to examine craniofacial structures in persons with hypodontia and to reveal any differences, that may occur, when agenetic teeth are only found in the maxilla, the mandible or in both jaws. The groups consistent of 50 children (33 girls, 17 boys) aged between 9 and 13.5 years were analyzed and assigned to three subgroups. Group 1 = upper jaw hypodontia. Group 2 = lower jaw hypodontia. Group 3 = hypodontia in both jaws.Materials and methodsEleven angular and three index measurements from lateral encephalographs and two linear measurements from dental blaster casts were calculated. All data was statistically analyzed, parameters with p < 5% were investigated for each subgroup respectively.ResultsIn comparison with standards the study group showed bimaxillary retrognathism and a reduction of the lower anterior facial height. Moreover both overbite and overjet significantly increased. Other values laid within the normal ranges. Evaluating results of the subgroups, differences in the means of SNA, SNB and overjet between the groups were observed.Analysis of the mandibular growth pattern revealed, that neither vertical nor horizontal patterns are dominant in hypodontia patients.ConclusionsIn certain dentofacial parameters differences between persons with hypodontia and such with full dentition exist. According to our findings agenetic teeth may have a negative influence on the saggital development of a jaw and the lower face and may be responsible for increased overbites. This should receive attention in orthodontic treatment of hypodontia patients.

Prevalence of hypodontia in the permanent dentition of Macedonian population

“…In women the prevalence was Figure 6 shows the total number of missing teeth in an individual in a study performed in 50 patients with hypodontia of more than one tooth 10 .…”

“…Evolutionary changes also have affect on diversity. Some researchers in their studies have come to a conclusion that the rate of hypodontia increases in time 2,11,16 , while others do not confirm that 10,12 .…”

“…1). The prevalence of hypodontia varies according to sex, race, geographic and demographic distribution, as well as ethnic affiliation 2,10,11 . Evolutionary changes also have affect on diversity.…”

“…Additionally, tooth agenesis can be followed by other conditions, as delayed tooth eruption, abnormalities in tooth shape, captured primary teeth, ectopic canines or taurodontism [7][8][9] . Also, tooth agenesis of permanent teeth has negative effect on the sagittal development of the jaw, as well as an increased vertical overlap (overbite) 10 .…”

Oral and dental late effects in survivors of childhood cancer: a Children’s Oncology Group report

“…The prevalence of hypodontia, which may alter craniofacial development and lead to malocclusion [14, 15], has ranged from 8.5 to 50 % depending on age at diagnosis, treatment modality, and study ascertainment methods [16–18]. In a CCSS report, childhood cancer survivors self-reported enamel hypoplasia more than twice as often as sibling controls (11.7 % versus 5.3 %) and were at higher risk for reporting root anomalies than siblings (odds ratio [OR]=3.0 [2.2–4.0]) [19].…”