Morphometric Development of the Mandible in Fetal Cadavers.

PURPOSE: The aim of this study is to present reliable data by measuring the morphometric properties of the mandible in the fetal period. METHODS: A study was performed on mandibles of 35 fetuses (18 male fetuses and 17 female fetuses), aged between 21 and 40 weeks of gestation. Fetuses were examined in 3 groups according to their developmental stages: 2nd trimester, 3rd trimester, and full-term. Morphometric measurements were performed for both the right and left sides of each mandible. The measurements of the mental foramen were performed using a digital caliper, and other measurements were performed using the ImageJ program. The data obtained were analyzed using the SPSS 20 for Windows program. RESULTS: There was no significant gender difference for all parameters. When the parameters were compared by the trimesters, no significant difference was determined in the 2nd trimester - 3rd trimester, 3rd trimester-full-term, and second trimester - full-term comparisons of the angle of the mandible, and there was a significant difference in all other parameters (P < 0.05). According to the trimesters, all parameters, except the angle of the mandible, increased naturally with the development of the mandible. It was observed that the angle of the mandible decreased from the 2nd trimester to the 3rd trimester and increased from the 3rd trimester to the full term. When the right and left measurements were compared, no significant difference was found for all parameters in both general and trimester groups. CONCLUSION: The present study includes fetal mandibular parameters that have not been reported elsewhere. It is thought that the obtained data will contribute to the determination of anomalies, pathologies, and variations.

Development of Hard and Soft Palate During the Fetal Period and Hard Palate Asymmetry.

In the present study, it was aimed to perform the morphometric analysis of the hard and soft palate in fetal cadavers and evaluate hard palate asymmetry during the fetal development. The development of the palate was investigated in 40 (21 males, 19 females) fetal materials aged between the 17th and 40th gestational week. In this study, distances between the incisive papilla-staurion (Ip-Sr), staurion-posterior nasal spine (Sr-Pns), incisive papilla-greater palatine foramen (Ip-Gpf) on the right and left sides, Sr-Gpf, and Pns-Gpf were measured. In cases with asymmetry, the ratio of asymmetry was determined in percentage using the asymmetry index. Moreover, angular values between Ip-Sr-Gpf and Ip-Pns-Gpf on the right and left sides were measured, and the right and left side values were compared with each other. The hard and soft palate lengths were measured on the planum medianum. Upon comparing the measured parameters between males and females, the mean values of male fetuses were higher in all parameters, but a significant difference was found only in the Sr-Pns distance among these parameters. Upon comparing the angular data and asymmetry index data on the hard palate between the trimester groups, a significant difference was found only in the Ip-Sr-Gpf (left) parameter. The mean ratio of the hard palate to the soft palate was found as 1.90. It is believed that the obtained data will contribute to studies to be conducted in fields such as plastic surgery, maxillofacial surgery, intrauterine surgery, fetopathology, embryology, anatomy, and obstetrics.

Whole-exome sequencing detects somatic mutations of IDH1 in metaphyseal chondromatosis with D-2-hydroxyglutaric aciduria (MC-HGA).

We used exome sequencing of blood DNA in four unrelated patients to identify the genetic basis of metaphyseal chondromatosis with urinary excretion of D-2-hydroxy-glutaric acid (MC-HGA), a rare entity comprising severe chondrodysplasia, organic aciduria, and variable cerebral involvement. No evidence for recessive mutations was found; instead, two patients showed mutations in IDH1 predicting p.R132H and p.R132S as apparent somatic mosaicism. Sanger sequencing confirmed the presence of the mutation in blood DNA in one patient, and in blood and saliva (but not in fibroblast) DNA in the other patient. Mutations at codon 132 of IDH1 change the enzymatic specificity of the cytoplasmic isocitrate dehydrogenase enzyme. They result in increased D-2-hydroxy-glutarate production, α-ketoglutarate depletion, activation of HIF-1α (a key regulator of chondrocyte proliferation at the growth plate), and reduction of N-acetyl-aspartyl-glutamate level in glial cells. Thus, somatic mutations in IDH1 may explain all features of MC-HGA, including sporadic occurrence, metaphyseal disorganization, and chondromatosis, urinary excretion of D-2-hydroxy-glutaric acid, and reduced cerebral myelinization.

Intrauterine maxillary development and maxillary dental arch biometry: a fetal cadaver study.

INTRODUCTION: This study's goal was to determine normal maxillary development on fetal cadavers. MATERIALS AND METHODS: This study was carried out on 45 fetuses aged between the 17th - 40th weeks of gestation (24 male, 21 female). The distance between the widest left and right points of the maxillary dental arch (MDA) on the transverse plane, the distance of the papilla incisiva (PI) to the widest left and right points of the maxillary dental arch (MDAW), and the PI and posterior nasal spine (PNS) were measured. The average arch forms of the MDA were created according to trimester groups using the MATLAB program. The one-way ANOVA test was used to make a comparison between trimester groups, and ANOVA followed by post hoc analysis using the Bonferroni test was applied for comparisons. Pearson's correlation analysis was used for correlation analysis. RESULTS: The data in the present study did not differ between genders. In the comparison between trimester groups, we did not find any difference between the 3rd trimester and full-term groups only in the PI-MDAW measurement. Other parameters increased with age. In the correlation analysis, the measurement values by age showed a strong positive correlation. The MDAW exhibited the best correlation with age (rweek = 0.919). When the average MDA forms created using the MATLAB program were evaluated, it was observed that the PI-MDAW of the average MDA in the 3rd trimester and full-term intersected. CONCLUSIONS: This study provides a basis for a better understanding of fetal maxillary growth processes and can be useful to standardize the detection of malformations or intrauterine growth restrictions.

A case with multiple accessory foramina of mandible in a fetus.

It is aimed to better recognize the mandibular variations by understanding the diversity and positions of accessory foramina better. Accessory formations on a full-term fetal mandible dissected for a mandibular study were examined under a microscope. To observe these formations more clearly, they were photographed with the help of a camera and microscope. In one of the mandibles dissected for a fetal mandibular study, a lateral accessory foramen (LAF1) was detected in the right half just near the mental foramen, and also a medial accessory foramen (MAF1) was detected over the mandibular foramen. In the left half, on the lateral surface relative to the mental foramen, one in the medial (LAF3) and one just above it (LAF2), and last one is near to the ramus of mandible (LAF4), three lateral accessory foramina, were detected. Again, a medial accessory foramen just above the left mandibular foramen (MAF3), and another foramen is near to mandibular symphysis (MAF2), also two medial accessory foramina on the lateral surface were detected. Detection and recognition of such variations are quite important for clinicians in the diagnostic methods and prevention of possible surgical complications.

Midline cleft of the lower lip associated with Robinow syndrome.

Robinow syndrome (also named "fetal face syndrome") includes a series of anomalies including mesomelic brachymelia, bifid terminal phalanges of the hands and feet, abnormalities of vertebrae and ribs, and hypoplastic external genitalia. A midline cleft of the lower lip and mandible is an extremely rare maxillofacial deformity. Seventy cases have so far been described to our knowledge. We report a patient with Robinow syndrome and midline cleft of the lower lip and mandible and describe the reconstruction of these anomalies. We propose that this anomaly should be added to the range of malformations associated with the syndrome.