Morphometry of the hard palate in Down's syndrome through CBCT-image analysis

Craniofacial and Airway Morphology in Down Syndrome: A Cone Beam Computed Tomography Case Series Evaluation

Background: Down syndrome (DS) is a genetic condition characterized by an extra copy of chromosome 21, resulting in various physical and cognitive features. This study aimed to comprehensively analyze the dental and craniofacial morphology of individuals with DS using Cone Beam Computed Tomography (CBCT). Methods: Six individuals with DS, comprising five males and one female aged 17 to 35 years, underwent CBCT scanning. Radiographic assessments included dentition, occlusion, paranasal sinuses, airway, skull bones, and suture calcification. Linear and angular cephalometric measurements were performed, and airway analysis was conducted using Dolphin 3D imaging software v.11. Results: The study revealed prognathic maxilla in five patients, prognathic mandible in four, and bimaxillary protrusion in two. Dental findings included microdontia, enamel hypoplasia, and congenitally missing teeth, with maxillary and mandibular third molars most commonly absent. Sinus abnormalities, delayed suture closure, and cervical spine anomalies were also observed. Conclusion: These findings contribute to a deeper understanding of DS-related craniofacial characteristics and emphasize the importance of considering these morphometric features in clinical management strategies for individuals with DS. This study's limited sample size underscores the significance of radiographic assessment in planning interventions such as cosmetic reconstructions, prosthetic rehabilitation, or orthodontic treatment for individuals with DS.

Minor physical anomalies including palatal rugae pattern and palatal dimensions in children with sickle cell disease: A cross-sectional analytical study

Background

Sickle cell disease (SCD) is the most common hereditary hemoglobinopathy, which delays growth leading to an altered skeleton and craniofacial pattern. Palatal rugae patterning has been considered the regulator of the development of the palate. The purpose of the research work was to study the morphology of the palate, rugae pattern, and its dimensions in SCD children and compare them with healthy normal children, and to evaluate its role as minor physical anomalies (MPAs).

Methods

A cross-sectional case-control study was designed as per STROBE guidelines. The sample comprised 50 children diagnosed with sickle cell disease (Group SCD) and 50 normal healthy children as control (Group C) belonging to the same age group (10-18 years). Dental impressions were made, followed by the pouring of dental casts. The length of the palatal rugae was measured and categorized into primary (>5 mm), secondary (3 mm-5 mm), and fragmentary rugae (<3 mm). The shape of each primary palatal rugae was identified and categorized as curved, wavy, straight, circular and non-specific. Linear and angular measurements of the palatal rugae patterns and palatal dimensions (width, height, area) were measured and recorded.

Results

The total number of palatal rugae and fragmentary rugae was lesser in Group SCD than in Group C (p < 0.05). The depth of the palate was significantly increased, whereas the area of the palate significantly decreased in Group SCD.

Conclusions

The children with SCD showed distinctive palatal rugae patterns and dimensions when compared with normal healthy children that can be attributed as potential MPAs for sickle cell disease. Children with SCD had an under-developed palatal rugae pattern with a deep, narrow and small palate when compared to healthy children.The dimensions of the palatal rugae pattern in SCD showed reduced distance between the incisive papilla and the first and last rugae, indicating a further decrease in the anteroposterior dimensions of the palate. These findings may aid in the early diagnosis and prevention of malocclusion in children with SCD by appropriate interceptive orthodontic treatment.

Vowel Production in Children and Adults With Down Syndrome: Fundamental and Formant Frequencies of the Corner Vowels

PURPOSE

Atypical vowel production contributes to reduced speech intelligibility in children and adults with Down syndrome (DS). This study compares the acoustic data of the corner vowels /i/, /u/, /æ/, and /ɑ/ from speakers with DS against typically developing/developed (TD) speakers.

METHOD

Measurements of the fundamental frequency (f o) and first four formant frequencies (F1-F4) were obtained from single word recordings containing the target vowels from 81 participants with DS (ages 3-54 years) and 293 TD speakers (ages 4-92 years), all native speakers of English. The data were used to construct developmental trajectories and to determine interspeaker and intraspeaker variability.

RESULTS

Trajectories for DS differed from TD based on age and sex, but the groups were similar with the striking change in f o and F1-F4 frequencies around age 10 years. Findings confirm higher f o in DS, and vowel-specific differences between DS and TD in F1 and F2 frequencies, but not F3 and F4. The measure of F2 differences of front-versus-back vowels was more sensitive of compression than reduced vowel space area/centralization across age and sex. Low vowels had more pronounced F2 compression as related to reduced speech intelligibility. Intraspeaker variability was significantly greater for DS than TD for nearly all frequency values across age.

DISCUSSION

Vowel production differences between DS and TD are age- and sex-specific, which helps explain contradictory results in previous studies. Increased intraspeaker variability across age in DS confirms the presence of a persisting motor speech disorder. Atypical vowel production in DS is common and related to dysmorphology, delayed development, and disordered motor control.

Morphometric Analysis of the Hard Palate Using Cone Beam Computed Tomography in a Saudi Population

Background and objectives

Analyzing the anatomical and morphometric information of the hard palate is crucial in prosthodontics, orthodontics, maxillofacial surgery, implant dentistry, and forensic anthropology. No data exist in the literature regarding the morphometric analysis of the hard palate using 3D imaging techniques in Saudi Arabia. Therefore, this study aimed to evaluate the dimensions and types of hard palates using 3D geometric morphometrics and the existence of gender-related differences in a selected Saudi population.

Material and methods

This cross-sectional study was performed by radiological evaluation of arbitrarily collected Cone Beam computed Tomography (CBCT) images includes 130 male and 45 female individuals from our department's archives, radiology department, Dental Hospital, Qassim University. The Galileos® Comfort Plus System (Sirona 3D, Germany) was used to obtain the CBCT images while standardizing the parameters. Images were linearly measured using Galileos software. Measurements of palatal length, palatal breadth, and palatal height, as well as the calculation of the palatine index and palatal height index, were noted and statistically analyzed.

Results

The mean palatal length, breadth, height, palatine index, and height index were 48.8 ± 3.9 mm, 36.2 ± 3.8 mm, 11.6 ± 2.4 mm, 74.7 ± 8.9, and 32.4 ± 7.1, respectively. The mean palatal length, breadth, and height were greater in men than in women. The majority of the palatine index values corresponded to leptostaphyline (76.6%), followed by mesostaphylline (12%) and brachystaphylline (11.4%), distribution among males and females were not statistical significance (p > 0.05). Palatal height index analysis revealed that the majority were orthostaphyline (59.4%), followed by chamestaphyline (26.3%), and hypsistaphyline (14.3%) these distributions were not significant statistically among males and females(p > 0.05).

Conclusion

The palatine index and palatine height index are useful in prosthodontics, orthodontics, and forensic anthropology for identifying races on the basis of the skull.

Panoramic radiographs and dental patients with Down syndrome: A scoping review

INTRODUCTION

Life expectancy for people with Down syndrome (DS) has increased to 60 years, although poor oral health affects their quality of life. Panoramic radiographs (PRs) are usually well-tolerated by people with DS and can provide valuable diagnostic data for treatment planning and research. Methods A scoping review of peer-reviewed articles published between 1971and 2021 was conducted in accordance with the PRISMA extension for scoping reviews to determine the scope of use of PRs for people with DS.

RESULTS

937 papers were screened, and 52 papers were included and charted into seven categories in this review. A high prevalence of tooth agenesis (TA) and other anomalies were reported in 45% of papers. Severe periodontal disease was considered characteristic of DS in the 1970s-80s and the benefit of time-consuming treatment was questioned. Since 2000 case reports illustrate that improved oral care, orthodontic treatment, and dental implants under local or general anaesthetic can improve the quality of life for people with DS.

CONCLUSION

PRs play an important role in the diagnosis of anomalies, periodontal disease, and implant planning for patients with DS. This review highlights the gaps in research of caries, pathology, TMJ, systemic disease indicators, and guidelines for dentists. Systematic PR viewing, with a knowledge of characteristic features of DS, will assist diagnosis of pathology and improve comprehensive dental care treatment planning for children and adults with DS.

Agreement among instruments of quantitative evaluation of the hard palate in children

PURPOSE

To evaluate the agreement among instruments of the quantitative evaluation of hard palate.

METHODS

This cross-sectional study was performed with a sample of 30 children aged 6 to 11 from Santa Maria, Southern Brazil. The instruments for palate measurements evaluated were: digital caliper, used directly in the oral cavity and in plaster casts, Korkhaus tridimensional bow, used directly in the oral cavity and in plaster casts, and Dolphin Imaging Software used for measurements in cone-beam computed tomography (CBCT). The agreement among different instruments was evaluated using the Intraclass Correlation Coefficient (ICC).

RESULTS

The means of all transversal dimensions obtained by cone-beam computed tomography were lower than those of the other instruments - the agreement values in the width between the canines and in the width between the first molars were lower when comparing the cone-beam computed tomography and the other instruments. In the width between the first and second premolars, all comparisons showed acceptable agreement values. Good concordance values were obtained when comparing the palate depth at the second premolar region when using a bow divider inside the oral cavity and in the cast.

CONCLUSION

Most instruments presented satisfactory agreement in the measurements related to the transverse plane of the hard palate. However, when the vertical plane was evaluated, only the bow divider applied to both cast and oral cavity presented ideal agreement.

Evaluation of the craniofacial and oral characteristics of individuals with Down syndrome: A review of the literature

The aim of this investigation was to describe the craniofacial and oral characteristics of children and/or adolescents with and without Down syndrome (DS). A bibliographic search of the Medline database (via PubMed), Scopus and SCIELO was performed using the keywords "craniofacial characteristics", "dental characteristics" and "Down syndrome". Systematic reviews, observational cross-sectional and longitudinal studies were included. On the contrary, case reports, letters to the editor, editorials and opinion articles were excluded. 251 articles were recovered, and only 30 fulfilled the selection criteria. DS patients were characterized by reduced dimensions of the maxillary bone, mandible, and skull base, compared to normal patients. Likewise, some of these abnormalities influenced more frequent presentation of a class III malocclusion in these patients. On the other hand, this population group showed a higher prevalence of periodontal diseases, less risk of dental caries, and the presence of alterations in the tongue, lips, dental development and palate morphology. The quality of life of these individuals is affected by difficulties in swallowing, talking, eating or breathing through the nose. In conclusion, the craniofacial and oral characteristics of DS patients present various alterations compared to healthy patients, and these alterations have a negative impact on their quality of life.

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 (r_week = 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.

Safe zones of the maxillary alveolar bone in Down syndrome for orthodontic miniscrew placement assessed with cone-beam computed tomography

The aim of this study was to quantify the available maxillary alveolar bone in a group of individuals with Down syndrome (DS) to determine the best areas for orthodontic miniscrew placement. The study group consisted of 40 patients with DS aged 12-30 years. We also selected an age and sex-matched control group. All measurements were performed on cross-sectional images obtained with cone-beam computed tomography. The selected areas of interest were the 4 interradicular spaces between the distal wall of the canine and the mesial wall of the second molar, in both maxillary quadrants. We measured the vestibular-palatine (VP) and mesiodistal (MD) dimensions to depths of 3, 6 and 9 mm from the alveolar ridge. We also measured the bone density in the same interradicular spaces of interest to 6 mm of depth from the alveolar crest. VP measurements were longer in the more posterior sectors and as the distance from the alveolar ridge increased. MD measurements also increased progressively as the distance from the alveolar ridge increased. In general, both the VP and MD measurements in the DS group were similar among the male and female participants. As age increased, the MD distance increased, while the VP distance decreased. The VP distance was ≥6 mm in at least 75% of the DS group in practically all assessed interdental spaces. The MD distance was ≥2 mm in at least 75% of the DS group only between the first and second molar, to 9 mm of depth from the alveolar ridge. The safe area for inserting orthodontic miniscrews in DS patients is restricted to the most posterior and deepest area of the maxillary alveolar bone.

Determination of mandibular morphology in a TURKISH population with Down syndrome using panoramic radiography

Background

Down syndrome (DS) is by far the most common known chromosomal disorder. Some characteristic features of DS are generalised growth deficiency, craniofacial abnormalities such as mandibular prognathism and underdevelopment of the midfacial region, dental abnormalities such as taurodontism and hypodontia. Individuals with DS have an increased prevalence of periodontal disease compared with age-matched control patients. The aim of the present study is to determine the morphologic features of the mandible among individuals with DS.

Methods

Thirty-four DS patients and thirty four age- and gender-matched control subjects underwent panoramic radiography, which included measurement of the mandibular canal (MC), the mandibular foramen (MF), the mandibular ramus (MR), the distance from the MC to the mandibular lower border (C-MLB), and the distance between the MC and the alveolar crest upper limit (C-AUL). Patients were separated into two groups based on age: < 15 (n = 15) and ≥ 15 (n = 19). In order to determine whether the MF, MR, MC, C-AUL, and C-MLB scores differed according to the groups (DS and control), one-way multivariate analysis of covariance (MANCOVA) was applied in which gender and age were taken as covariates.

Results

When the main effect according to the group was examined separately according to each measurement, the MF in the DS group was high with a moderate effect (F = 9207; p = 0.003). MR (F = 40,518; p < 0.001), MC (F = 23,747; p < 0.001), and C-AUL (F = 58,571; p < 0.001) in the DS group were lower with a larger effect. C-MLB did not significantly differ between the groups, and the effect size was quite low (p > 0.05).

Conclusions

Mandibular canal morphology may exhibit anatomical variations in DS. The alveolar bone level may differ from non-DS due to growth development retardation and/or periodontal diseases.

Reassessment of fluctuating dental asymmetry in Down syndrome

Fluctuating dental asymmetry (FDA) is a tool to measure developmental stability that could be increased in gonosomal aneuploidies. The aim of this study was to quantify FDA in individuals with Down syndrome (DS). The study group comprised 40 individuals with DS, and a control group matched for age and sex was created. The target teeth were the maxillary central incisors (11,21), maxillary lateral incisors (12,22), maxillary canines (13,23), and maxillary first molars (16,26). Dental morphometric variables measured on CBCT images included tooth length, crown height, root length, mesio-distal diameter, crown-to-root ratio, vestibular-palatine diameter, mid mesio-distal diameter, mid buccal-palatal diameter, maximum buccal-palatal diameter, and cervical circumference. The FA2 fluctuating asymmetry index (Palmer and Strobeck, 1986) was applied. Some discrepancies in crown-to-root ratios and root length asymmetry were significantly lower in the DS individuals than in controls. Combining the crown-to-root ratio of tooth 11 versus 21, tooth 12 versus 22, and tooth 13 versus 23, we developed a predictive model with a discriminatory power between DS and controls of 0.983. Some dental morphometric variables may actually be more stable in DS individuals than in the general population. This offers a new perspective on the relationship between canalization, fluctuating asymmetry, and aneuploidy.

Growth of the hard palate in infants with Down syndrome compared with healthy infants-A retrospective case control study

OBJECTIVE

To investigate morphological differences of the hard palate in infants with Down syndrome (DS) compared with a volumetric-matched control group (CG).

METHODS

Trial design: retrospective case control study. Based on inclusion and exclusion criteria, plaster casts of edentulous maxillae of 40 DS infants (20 females and 20 males, aged 221.3 ± 132.4 days) and 40 CG infants (20 females and 20 males, aged 53.9 ± 87.2 days) were digitized and converted into 3-dimensional stereolithography data. An automated landmark- and investigator-independent method for assessing two-dimensional measurements such as width, depth, and length of palate, as well as palatal index and the 3-dimensional volume, were used.

RESULTS

Matching DS and healthy CG infants by age, we found reduced sizes in all linear and volumetric measurements in the DS group. Matching both groups by palatal volume, we found no differences between the groups according to palatal width (p = .93), palatal depth (p = .32), and palatal index (p = .31). Control infants with the same palatal volume compared with the DS infants were about 151 days younger, 95%-CI = [102, 200] (Hodges-Lehmann estimator). Except for palatal length and palatal volume, the growth pattern of DS palates decreased irregularly at age 6 to 9 months.

CONCLUSIONS

The palate of DS infants in the first 6 to 9 month of life is of normal shape but considerably smaller compared with healthy normals. From 6 to 9 months onward, the growth pattern of the hard palate in DS infants decreases irregularly. High-arch-constricted palates could, therefore, be interpreted as secondarily acquired in later life. We therefore speculate that it could be advantageous to begin oral muscular stimulating therapy between 6 and 9 months of age which may prevent palatal shape alterations and enhance oral function which also contributes to maxillary development.