Partial anodontia; a brief review and a case report of multiple familial incidence

Prosthetic management of partial anodontia with microdontia from 11 to 20 years of age - 10 years of follow up

Treatment of pediatric patients with partial anodontia is a challenge requiring interdisciplinary approach. Growth period, reduced vertical dimension, microdontia, and unacceptable esthetics present difficulties at various stages of prosthetic rehabilitation. Congenital absence of teeth impairs the nutritional status of the growing child and causes a psychological setback. This article describes the prosthetic management of a patient suffering from partial anodontia done over a period of 10 years. Considering the age and psychological and financial requirements of the patient, removable and fixed prostheses were fabricated at different phases of the treatment. The ultimate aim was restoration of function, improvement of esthetics, and overall psychological upliftment of the patient which was achieved by maxillary metal ceramic bridge and mandibular implant retained hybrid prosthesis.

The association between WNT10A variants and dental development in patients with isolated oligodontia

In this study we aimed to determine the effect of WNT10A variants on dental development in patients with oligodontia. Forty-three (25 boys and 18 girls) individuals were eligible for this study. Stage of development for each present tooth was assessed using the Demirjian method. In case no corresponding tooth was present, regression equations were applied for dental age to be calculated. The ratio between length of root and length of crown was ascertained for each present tooth in all quadrants. All patients were physically examined by a clinical geneticist and DNA analysis of the WNT10A gene was performed. Linear regression models were applied to analyze the association between WNT10A variants and dental age. The same analysis was applied to study the association between WNT10A variants and root elongation for each present tooth. One ordinal regression model was applied to analyze the association between WNT10A variants and development of present maxillary and mandibular teeth. Thirty-six (84%) patients were detected with WNT10A variants of which six patients displayed evident ectodermal features. Dental age was 1.50 (95% confidence interval (CI): -2.59, -0.42) to 1.96 (95% CI: -3.76, -0.17) years lower in patients with WNT10A variants compared with patients without variants. The development of maxillary canine, maxillary second molar and mandibular second molar was statistically significantly delayed in patients with WNT10A variants compared with patients without variants. The impact of WNT10A variants on dental development increases with presence of the nonsense c.(321C>A p.(C107*)) variant and the number of missing teeth.

Birth weight and congenital absence of teeth in twins

The relationship between hypodontia and birth weight was investigated in 262 twins from the naval recruit population at Great Lakes. The overall frequency of hypodontia including third molars was 34.8%. Excluding third molars, hypodontia frequency was 11.6%. Anatomic distribution of congenitally missing teeth and frequency of third molar hypodontia were similar to other studies, but hypodontia of teeth other than third molars occurred two-three times as frequently in twins as in the general population.

The frequency of low birth weight (2500 g or less) in the twin sample was 47.7%. Hypodontia occurred more frequently in twins with low birth weight (42.6%) than in twins with birth weights over 2500 g (28.6%). Mean birth weight of twins with hypodontia was 2479 g, and without hypodontia, 2675 g. Twins with missing teeth other than third molars had a mean birth weight of 2357 g.

Mean birth weight was lower and hypodontia frequency was higher in MZ than in DZ twins. Discordances in anatomic location and number of missing teeth occurred in several MZ and DZ twin pairs. Discordances within MZ sets tended to be related to anatomic location rather than number of missing teeth. Six twin pairs (5 MZ and 1 DZ) out of 20 (13 MZ and 7 DZ) having one or more missing teeth had perfect concordance in both number and location of missing teeth. In 28 pairs neither member had hypodontia.

Mean intrapair variance in number of congenitally missing teeth was almost ten times greater in DZ than in MZ pairs, indicating the presence of a strong genetic component in connection with tooth number variability in twins.