Morphology Study Of Naso-maxillary Complex In Male Children With Hypohidrotic Ectodermal Dysplasia

ObjectiveHypohidrotic ectodermal dysplasia(HED)was a congenital genetic disorder characterized by anhidrosis or hypohidrosis,edentulous or edentulous,and hairless,often accompanied by maxillofacial dysplasia.The naso-maxillary complex constituted the main body of the midface,and its morphology was important for functional treatment of HED patients.This study intended to analyze the morphological of naso-maxillary complex and maxillary sinus of male children with HED from a three-dimensional perspective through the measurement of CBCT(cone beam computed tomography),and to explore the clinical characteristics of dentition in HED patients,so as to provide a reference for the early treatment of this type of disease.MethodsMale children clinically diagnosed as HED in the Children’s Stomatology Department of Shandong University Stomatology Hospital from August 2017 to March 2023 were collected as the experimental group,and normal skeletal Class I children admitted during the same period as the control group.With the informed consent of the children’s guardians,a specialist examination of the children’s face and mouth was performed,and facial and oral images were taken and CBCT was taken.The CBCT data of the two groups were imported into Mimics(materialise’s interactive medical image control system)software for modeling,cephalic correction and landmark selection,and the three-dimensional data of the naso-maxillary complex and its internal maxillary sinuses were obtained.The horizontal indexes of naso-maxillary complex included maxillary basal bone width,midface width,zygomatic process width,bony palpebral fissure width and the most medial orbital distance.Sagittal indexes included anterior skull base length and midface depth.The vertical indices included midface height and complex relative height.Maxillary sinus indexes included anteroposterior diameter,width,craniocaudal diameter and volume.The morphological and developmental differences of naso-maxillary complex and its internal maxillary sinuses between HED male children and their peers were compared.Statistical analysis of dentition data in children with HED.SPSS 26.0 was used to analyze the measured data,and P<0.05 was statistically different.ResultsA total of 18 patients in the experimental group were included,with an average age of 5.67 years.There were 20 cases in the control group,with an average age of 5.65 years.The three-dimensional morphology of the nasal-maxillary complex of HED male children:Horizontal direction:The measurement results of maxillary basel bone width,midface width and zygomatic process width in the experimental group were smaller than those in the control group,and there were statistical differences in maxillary basel bone width,midface width and zygomatic process width between the two groups(P<0.05).There was no significant difference in the bony palpebral fissure width and the most medial orbital distance between the two groups(P>0.05).Sagittal direction:The measurement results of anterior skull base length and midface depth in the experimental group were smaller than those in the control group,and there were statistical differences in the anterior skull base length and midface depth between the two groups(P<0.05).Vertical direction:The measurement results of midface height and complex relative height in the experimental group were smaller than those in the control group,and there were statistical differences in the midface height and complex relative height between the two groups(P<0.05).Maxillary sinus morphology:There were no significant differences in anteroposterior diameter,width,craniocaudal diameter and volume of the maxillary sinus between the left and right sides(P>0.05).The results of anteroposterior diameter,width and volume of maxillary sinus in the experimental group were smaller than those in the control group,and there were statistical differences in anteroposterior diameter,width and volume of maxillary sinus between the two groups(P<0.05),while there was no significant difference in craniocaudal diameter of the maxillary sinus between the two groups(P>0.05).Condition of dentition in 17 male children with HED:The average number of missing teeth in primary dentition was 15.06 and the average number of malformed teeth was 2.47.There were 2 cases of maxillary and mandibular dentition loss;6 cases of mandibular dentition loss and maxillary dentition defect;9 cases of maxillary and mandibular dentition defect.The incidence of mandibular dentition loss was 47.06%(8/17)and the incidence of maxillary dentition loss was 11.76%(2/17).All the children lacked mandibular primary central incisor teeth.The most commonly retained teeth in the maxillary and mandibular dentition both was the second primary molar,and all anterior primary teeth were conical malformed teeth.Conclusion(1)The width of naso-maxillary complex was insufficient at zygomatic level,zygomatic arch level and zygomatic alveolar ridge level in male children with HED.(2)The naso-maxillary complex was underdeveloped in length and height in male children with HED.(3)The anteroposterior diameter,width and volume of maxillary sinuses were underdeveloped in male children with HED.(4)The number of missing teeth in the mandible of primary dentition was greater than that in the maxillary dentition in male children with HED.