Periodontal disease in patients with Down syndrome: A systematic review

Development and evaluation of a new website on oral health and Down syndrome

AIMS

The objective of this study was to develop a new website in Spanish on oral health and dental care for use by the relatives/caregivers of individuals with Down syndrome, with the aim of incorporating the strengths and avoids the deficiencies of existing websites.

METHODS

A freely accessible website was developed with dental content, whose access criteria included the age of the individual undergoing the consultation and the area of interest (tongue or teeth disease, oral functionality, oral hygiene, and dental visits). The definitive version of the website was analyzed by five external examiners, applying the DISCERN criteria and the Questionnaire to Evaluate Health Web Sites According to European Criteria (QEEC). The website's traffic during the first year of activity was recorded.

RESULTS

The new website is known as "DentiDown", and its access domain is https://odontoloxia-accessible.org/dentidown/. On the home screen, the age group of interest to the user can be accessed. A dropdown menu then opens, listing the various options according to the area of interest. The oral hygiene section provides advice for improving toothbrushing efficacy through demonstration videos. With the DISCERN tool, an overall score of 4.75 ± 0.5 was achieved. With the QEEC, the external examiners' general opinion was highly favorable. The website received the seal of quality from the Accredited Medical Web (AMW). During the first year of activity, a total of 4536 visits from a total of 45 countries were recorded.

CONCLUSION

A new Spanish website has been developed on oral health for use by the relatives/caregivers of individuals with Down syndrome. The website has been favorably evaluated by external experts and, to date, is the only one with these characteristics with the AMW seal of quality.

Factors associated with halitosis reported by parents/caregivers in individuals with Down syndrome

AIMS

Data on halitosis among individuals with Down syndrome (DS) are scarce. The aim was to evaluate factors associated with the occurrence of halitosis reported by parents/caregivers (P/Cs) in individuals with DS.

METHODS AND RESULTS

A cross-sectional study was conducted in non-governmental assistance institutions in the State of Minas Gerais-Brazil. P/Cs have answered an electronic questionnaire with sociodemographic, behavioral and oral health data. Factors associated with halitosis were evaluated by multivariate logistic regression. The sample comprised 227 P/Cs (age 48.8 ± 13.2 years; 82.9% mothers) of individuals with DS (age 20.8 ± 13.5 years). The prevalence of halitosis in the total sample was 34.4% (n = 78) and its occurrence was associated: 1) in individuals with DS ≤18 years old (26.2%; n = 27)-negative perception of oral health (OR = 3.91); 2) in individuals with DS > 18 years (41.1%; n = 51)-gingival bleeding (OR = 4.53), absence of tongue brushing (OR = 4.50), negative perception of oral health (OR = 2.72).

CONCLUSIONS

The occurrence of halitosis in individuals with DS reported by P/Cs was relevant and associated with dental factors, having a negative impact on the perception of oral health. Oral hygiene practices, especially tongue brushing, should be reinforced to prevent and control halitosis.

Association of Down syndrome with periodontal diseases: Systematic review and meta-analysis

BACKGROUND

Down syndrome (DS) is distinguished by cognitive disability, a concave profile, and systemic complications. Oral diseases have been reported to be common in DS patients.

OBJECTIVE

To investigate the association between DS and periodontal diseases.

METHODS

Two independent reviewers searched six bibliographic databases up to January 2023 and used additional search methods to identify published studies on gingivitis or periodontitis in people with and without DS. Meta-analysis, risk of bias, sensibility analysis, publication bias, and evidence grading were all carried out.

RESULTS

Twenty-six studies were included for analysis. There was a tendency for increased plaque accumulation, periodontal probing, periodontal attachment level, bleeding on probing and indices in DS individuals. Meta-analysis of 11 studies showed a significant association between DS and periodontitis (OR 3.93; 95% CI 1.81-8.53). Probing depth was significantly high in individuals with DS as compared to controls (mean difference 0.40 mm; 95% CI 0.09-0.70). Gingivitis was significantly associated (OR 1.93; 95% CI 1.09-3.41) with DS in four studies. The evidence was classified as 'moderate certainty'.

CONCLUSION

Medium/low-quality studies demonstrate that Down syndrome is strongly associated with periodontitis and moderately associated with gingivitis.

Periodontal disease in down syndrome: Predisposing factors and potential non-surgical therapeutic approaches

BACKGROUND

Periodontal diseases (PDs) have been documented to be significantly more prevalent and severe in patients with Down syndrome (DS). Different immunological and microbiological factors contributed to predisposing these patients to progressive and recurrent PDs.

AIM

The aim of this review was to investigate the altered immunological responses and oral microbiota disorders as well as focus on adjunctive non-surgical methods for the treatment of PDs and its applicability in patients with DS.

MATERIAL AND METHODS

A literature review was conducted addressing the following topics: (1) the altered immunological responses, (2) orofacial disorders related to DS patients, (3) oral microbiota changing, and (4) adjunctive non-surgical treatment and its efficacy in patients with DS.

RESULTS

Due to the early onset of PDs in children with DS, the need for prompt and effective treatment in these patients is essential.

DISCUSSION AND CONCLUSION

So, investigating underlying factors may open a new window to better understand the pathology of PDs in DS people and thus, find better strategies for treatment in such group. Although non-surgical treatments such as photodynamic therapy and probiotic consumption represented acceptable outcomes in different examined patients without DS, data about the application of these convenience and no need for local anesthesia methods in patients with DS is limited.

Lateral cephalometric characteristics in individuals with Down Syndrome compared to non-syndromic controls: A meta-analysis

OBJECTIVES

The aim of the present meta-analysis was to provide a complete synthesis of all studies involving lateral cephalometric measurements in populations with Down Syndrome (DS).

METHODS

A literature search was carried out using six electronic databases to identify studies comparing cephalometric characteristics between populations with DS and control (healthy) populations. Studies were selected according to the research objectives, and predefined inclusion and exclusion criteria. Only the cephalometric measurements included in three or more studies selected were analyzed. The random-effects meta-analysis model was used for data analysis, and all analyses were carried out using RevMan5 software.

RESULTS

From an initial 871 articles identified through the literature search, ten cross-sectional studies were finally selected based on the inclusion and exclusion criteria. Ten cephalometric measurements underwent meta-analysis, five linear and five angular measurements. Concerning the five linear measurements, namely S-N, ANS-PNS, Go-Gn, Ar-Go, and N-ANS, all were significantly smaller in the DS group with the exception of Go-Gn. Of the five angular measurements, only three were statistically different between the DS and control groups. SNB and ANB angles were smaller in individuals with DS, whereas the basilar angle was larger. Subgroup analysis was also carried out based on age, and it was found that the gonial angle was significantly smaller before puberty, in individuals with DS. No differences between groups were found for the SNA angle.

CONCLUSION

There are significant cephalometric differences between individuals with and without DS. Individuals with DS have a shorter anterior cranial base, maxillary length, upper anterior facial height and mandibular height. The ANB and SNB angles were also smaller in those with DS, but the SNA angle showed no differences. These findings may indicate that the Class III malocclusion commonly found in individuals with DS does not seem to be due to mandibular prognathism.

CLINICAL RELEVANCE

Lateral cephalometric measurements in individuals with DS show significant differences from individuals without DS. Practitioners need to be aware of this and monitor growth from an early age in these children.

Otitis Media in Children with Down Syndrome Is Associated with Shifts in the Nasopharyngeal and Middle Ear Microbiotas

Background: Otitis media (OM) is defined as middle ear (ME) inflammation that is usually due to infection. Globally, OM is a leading cause of hearing loss and is the most frequently diagnosed disease in young children. For OM, pediatric patients with Down syndrome (DS) demonstrate higher incidence rates, greater severity, and poorer outcomes. However, to date, no studies have investigated the bacterial profiles of children with DS and OM. Method: We aimed to determine if there are differences in composition of bacterial profiles or the relative abundance of individual taxa within the ME and nasopharyngeal (NP) microbiotas of pediatric OM patients with DS (n = 11) compared with those without DS (n = 84). We sequenced the 16S rRNA genes and analyzed the sequence data for diversity indices and relative abundance of individual taxa. Results: Individuals with DS demonstrated increased biodiversity in their ME and NP microbiotas. In children with OM, DS was associated with increased biodiversity and higher relative abundance of specific taxa in the ME. Conclusion: Our findings suggest that dysbioses in the NP of DS children contributes to their increased susceptibility to OM compared with controls. These findings suggest that DS influences regulation of the mucosal microbiota and contributes to OM pathology.

A Comparative Evaluation of Physical Parameters of Saliva and Correlation with Periodontal Condition in Down Syndrome Children and Healthy Controls

AIM

The aim of this study was to assess the significance and role of physical parameters of saliva on periodontal health in children with Down syndrome (DS).

MATERIALS AND METHODS

A comparative evaluation of physical parameters of saliva such as flow rate, viscosity, pH, quantity and buffering capacity, and buffer capacity was carried out using GC Saliva-Check Buffer kit and correlated with periodontal condition examined using community periodontal index of treatment needs (CPITN) in 40 DS subjects (group I) and 40 healthy controls (group II) aged 8-15 years.

RESULTS

Down syndrome subjects had a low resting salivary flow rate, moderately acidic saliva, very low quantity of stimulated saliva, and low buffering capacity. On correlating salivary parameters with the periodontal condition, DS subjects with CPITN code 1 had low resting salivary flow rate, normal viscosity, moderately acidic pH, very low quantity of stimulated saliva, and low buffering capacity. Down syndrome subjects with CPITN code 2 had low resting flow rate, increased viscosity, very low quantity of stimulated saliva, low buffering capacity, and moderately acidic pH. Healthy controls with CPITN code 0 had normal resting flow rate, viscosity of saliva, quantity of stimulated saliva, buffering capacity, and moderately acidic pH.

CONCLUSION

Compared to healthy controls, DS subjects showed decreased values for resting flow rate, pH, quantity of stimulated saliva, and buffering capacity. A statistically significant correlation was observed between the physical parameters of saliva and periodontal condition in DS subjects (p < 0.05).

CLINICAL SIGNIFICANCE

Periodontal diseases start at a very early age and periodontal health deteriorates at a faster rate in DS children for which saliva also plays its part. Prime importance should be given to frequent oral hygiene and preventive measures in DS children thus preventing accumulation of debris and plaque.

Orofacial findings and orthodontic treatment conditions in patients with down syndrome - a retrospective investigation

INTRODUCTION

The most common chromosomal anomaly is Down syndrome/Trisomy 21, which can be associated with varying degrees of intellectual disability and physical malformation. Specific orofacial characteristics regarding orthodontic treatment options and features are described on the basis of a patient collective from the Witten/Herdecke University, Germany.

METHODS

Data of 20 patients (14 boys and 6 girls, mean age: 11.69 ± 3.94 years) who underwent orthodontic treatment between July 2011 and May 2022 were analyzed. Baseline skeletal and dental conditions were assessed, as well as the presence of hypodontia, displacements, and treatment-related root resorptions. The treatment need was evaluated based on the main findings according to the German KIG classification. In addition, treatment success was determined in relation to patient compliance.

RESULTS

The patient group was characterized predominantly by a class III relationship (ΔANB: -2.07 ± 3.90°; ΔWITS: -3.91 ± 4.33 mm) and a brachyfacial cranial configuration (ΔML-NL: -4.38 ± 7.05°, ΔArGoMe: - 8.45 ± 10.06°). The transversal discrepancy of the dental arch width from maxilla to mandible was -0.91 ± 3.44 mm anteriorly and -4.4 ± 4.12 mm posteriorly. Considering the orthodontic indication groups, the most frequent initial finding and treatment indication represented hypodontia (85%), followed by frontal (75%) and unilateral lateral (35%) crossbite. In 55% of the cases, the teeth had a regular shape, but in 35% a generalized and in 15% an isolated hypoplasia. Only 25% of the patients could be treated with a fixed multiband appliance due to sufficient cooperation. In each of these patients, varying degrees of root resorptions were detected during treatment, and 45% of all treatments had to be terminated prematurely due to a lack of cooperation by patients or parents.

CONCLUSION

The extent of dental and skeletal malformations and the high rate of findings requiring treatment in patients with Down syndrome represent a significant indication for orthodontic therapy, which can be well illustrated by the KIG classification. However, this is in contrast to the eventually increased risk of root resorption, with significantly reduced patient cooperation. A compromised treatment outcome and process must be expected. Consequently, the orthodontic treatment must be simple and realistic to achieve fast and therapeutically satisfactory treatment result.

Cross-sectional study of the factors associated with the number of teeth in middle-aged and older persons with intellectual disabilities

BACKGROUND

We investigated the number of teeth in middle-aged and older individuals with intellectual disability and evaluated the related factors.

METHODS

A questionnaire survey on oral health was administered to 604 persons over 40 years old with intellectual disabilities in Aichi Prefecture, Japan. The questionnaire designed for this study included items on diagnosis of disability, severity of intellectual disability and type of residence. As oral-health-related factors, the proxy-reported number of teeth, family dentist, regular dental check-ups, problems during dental treatment and tooth-brushing frequency were evaluated. A multinomial logistic regression analysis was performed using the proxy-reported number of teeth (≥20, 10-19 or 0-9) as the dependent variable, and the odds ratios (ORs) and 95% confidence intervals (CIs) of independent variables were calculated. In addition, linear regression analysis was performed using the proxy-reported number of teeth as the dependent variable.

RESULTS

In the multivariate multinomial logistic regression analysis, age, diagnosis of disability and type of residence were significantly associated with having 10-19 versus ≥20 teeth. Participants with autism spectrum disorder had a significantly lower OR for 10-19 teeth compared with those with intellectual disability [OR (95% CI): 0.49 (0.22-1.08)]. Age, diagnosis of disability, regular dental check-ups and tooth-brushing frequency were significantly associated with having 0-9 versus ≥20teeth. Participants with Down syndrome had a significantly higher OR for 0-9 teeth compared with those with intellectual disability [OR (95% CI): 3.17 (1.09-9.23)]. The ORs for 0-9 teeth of participants who did not attend regular dental check-ups and who brushed their teeth 1 time/day compared with ≥3 times/day were significantly high, and the OR (95% CI) was 2.37 (1.06-5.30) and 4.76 (1.09-20.77), respectively. [Corrections made on 22 August 2022, after first online publication: in the previous sentence, "who attend" has been changed to "who did not attend".] In the multivariate linear regression analysis, age, diagnosis of disability and regular dental check-ups were significantly associated with the proxy-reported number of teeth. The proxy-reported number of teeth was -0.42 less with each 1-year increase in age. With autism spectrum disorder, the proxy-reported number of teeth was 0.74 more compared with intellectual disability. In Down syndrome, the proxy-reported number of teeth was -0.93 less compared with intellectual disability. The proxy-reported number of teeth was -2.12 less for those who did not have regular dental check-ups.

CONCLUSIONS

The number of teeth in middle-aged and older individuals with intellectual disability was related to age and the type of disability. Regular dental visits may be effective at preventing tooth loss in middle-aged and older persons with intellectual disability.

Oral Health Care of People with Down Syndrome in Germany

BACKGROUND

Due to a dearth of information on preventive and supportive oral care for people with Down Syndrome (PDS) in Germany, caregivers of PDS were surveyed on the topic.

METHODS

An anonymized questionnaire was sent to the 610 members of the German Down Syndrome Association. The study was approved by the ethics committee of Witten/Herdecke University (# 165/2017).

RESULTS

The parents/caregivers of 207 PDS responded. These PDS were between 1 and 55 years old (mean age 24.4 years) and included 111 males and 96 females. At their first dental appointment, 40.7% (n = 82) had been younger than three years. Although 78.3% (n = 162) tooth brushed twice daily, only 30.9% (n = 64) brushed for 2-3 min; 84.0% (n = 135) did not use other dental hygiene products apart from toothbrushes. Age-specific differences were found: Although only 30.8% (n = 12) of PDS < 18 years (n = 39) independently performed dental self-care; this was 67.3% (n = 113) for PDS ≥ 18 years (n = 168). A statistically significant (p < 0.001; Chi-Square-Test) difference in toothbrush preferences emerged: While PDS < 18 years mainly used manual toothbrushes, PDS ≥ 18 years preferred electric toothbrushes. In contrast to 72.6% of PDS ≥ 18 years, only 51.3% of PDS < 18 years accepted most types of toothpaste.

CONCLUSIONS

Age-dependent differences in tooth brushing behaviour became evident within the group of PDS in Germany. Hence, better age-specific, inter-professional dental prophylaxis concepts need to be developed and offered for all age groups of PDS. These concepts should include personalized check-up intervals and hands-on instruction in dental hygiene procedures by dental practitioners.

Oral health characteristics of patients living with intellectual disability at transition phase from pediatric dental service to adult dental service: A systematic review

AIM

A systematic review was conducted to evaluate the available literature to ascertain the oral health characteristics of patients living with intellectual disability when they transfer from pediatric dental service to adult dental service.

MATERIAL AND METHODS

The electronic search was performed between June 2020 and July 2020 using the following databases: MEDLINE and EMBASE. Cochrane database, gray literature, and Google Scholar were also searched. References of articles obtained from the electronic searches were scanned through. Journals and regulation agency websites were also hand searched. This systematic review used a defined search strategy keywords for all the electronic databases. The strength of evidence in these studies was evaluated using the British Medical Journal quality assessment tool.

RESULTS

The search process identified 45 eligible articles. Of these, 35 studies were excluded, and 10 observational studies were included.

CONCLUSION

It seems that a considerable percentage of patients living with intellectual disability in their transition phase, aged between 18 and 25 years, have a high prevalence of dental caries, gingivitis, and periodontal disease when compared to the general population.

Identification of Neuropeptides as Potential Crosstalks Linking Down Syndrome and Periodontitis Revealed by Transcriptomic Analyses

Background

This bioinformatics study was aimed to investigate the relationship between periodontitis (PD) and Down Syndrome (DS) regarding potential crosstalk genes, related neuropeptides, and biological processes.

Methods

Data for PD (GSE23586, GSE10334 and GSE16134) and DS (GSE35665) were downloaded from NCBI Gene Expression Omnibus (GEO). Following normalization and merging of PD data, differential expression analysis was performed (p value < 0.05 and ∣log FC | ≥0.5). The common deregulated genes between PD and DS were considered as crosstalk genes. The significantly differentially expressed genes were used to construct the coexpression network and to further identify coexpression gene modules. To acquire the significant modules, the significant expression level of genes in the module was used to analyze the enrichment of genes in each module. Neuropeptides were assessed from NeuroPedia database. Neuropeptide genes and crosstalk genes were merged and mapped into PPI network, and the correlation coefficient (Spearman) was determined for the crosstalk genes.

Results

138 crosstalk genes were predicted. According to the functional enrichment analysis, these genes significantly regulated different biological processes and pathways. In enrichment analysis, the significant module of DS was pink module, and turquoise module was significant in PD. Four common crosstalk genes were acquired, i.e., CD19, FCRL5, FCRLA, and HLA-DOB. In the complex network, INS and IGF2 interacted with CASP3 and TP53, which commonly regulated the MAPK signaling pathway. Moreover, the results showed that TP53 interacted with IGF2 and INS inducing the dysregulation of PI3K-Akt signaling pathway. UBL was positively correlated with crosstalk genes in both diseases. LEP was revealed to be both a neuropeptide and crosstalk gene and was positively correlated with other crosstalk genes.

Conclusion

Different crosstalk genes, related neuropeptides, and biological pathways and processes were revealed between PD and DS, which can serve as a theoretical basis for future research.

Oral Microbiota Features in Subjects with Down Syndrome and Periodontal Diseases: A Systematic Review

Down syndrome (DS) is a genetic disorder associated with early-onset periodontitis and other periodontal diseases (PDs). The present work aimed to systematically review the scientific literature reporting studies in vivo on oral microbiota features in subjects with DS and related periodontal health and to highlight any correlation and difference with subjects not affected by DS, with and without PDs. PubMed, Web of Science, Scopus and Cochrane were searched for relevant studies in May 2021. The participants were subjects affected by Down syndrome (DS) with and without periodontal diseases; the study compared subjects with periodontal diseases but not affected by DS, and DS without periodontal diseases; the outcomes were the differences in oral microbiota/periodontopathogen bacterial composition among subjects considered; the study design was a systematic review. Study quality was assessed with risk of bias in non-randomized studies of interventions (ROBINS-I). Of the 954 references retrieved, 26 studies were considered. The conclusions from the qualitative assessment of the papers revealed an increasing knowledge over the last years of the microbiota associated with DS and their periodontal diseases, in comparison with healthy subjects and subjects with other kinds of mental disabilities. Few data have emerged on the mycobiome and virobiome of DS, hence, further investigations are still necessary.

Prevalence and incidence of physical health conditions in people with intellectual disability - a systematic review

OBJECTIVE

To synthesize evidence on the prevalence and incidence of physical health conditions in people with intellectual disability (ID).

METHODS

We searched Medline, PsycInfo, and Embase for eligible studies and extracted the prevalence, incidence, and risk of physical health conditions in people with ID.

RESULTS

Of 131 eligible studies, we synthesized results from 77 moderate- to high-quality studies, which was mainly limited to high-income countries. The highest prevalence estimates were observed for epilepsy, ear and eye disorders, cerebral palsy, obesity, osteoporosis, congenital heart defects, and thyroid disorders. Some conditions were more common in people with a genetic syndrome. Compared with the general population, many health conditions occur more frequently among people with ID, including asthma and diabetes, while some conditions such as non-congenital circulatory diseases and solid cancers occur at the same or lower rate. The latter associations may reflect under-detection.

CONCLUSIONS

People with ID have a health profile more complex than previously known. There is a pressing need for targeted, evidence-informed population health initiatives including preventative programs for this population.

Periodontal status of individuals with Down syndrome: sociodemographic, behavioural and family perception influence

BACKGROUND

The aim of the present study was to assess the periodontal condition of individuals with Down syndrome and the association with sociodemographic and behavioural characteristics and family perception of oral health.

METHODS

This cross-sectional observational study was performed at a referral centre for dental assistance to disabled persons in Araçatuba, Brazil. Parents of the individuals were interviewed, and the visible plaque index, bleeding on probing, probing pocket depth and clinical attachment level were recorded by one periodontist in six sites per tooth of all teeth. The individual was the unit of analysis. The significance level was set at 5%.

RESULTS

Sixty-four subjects (23.8 ± 8.3 years old) were included. Eighteen (28.1%) were diagnosed with gingivitis and 46 (71.9%) with periodontitis. In the multiple logistic regression final model, age and self-reported oral hygiene practices were associated with the occurrence of periodontitis. The chance of having periodontitis was 4.7 times higher among individuals older than 20 years and approximately 4 times higher in patients whose oral hygiene was performed by themselves and their parents, compared with those who performed oral hygiene alone. Sex, follow-up time in the centre, education, degree of participants' dependence, flossing and family history of periodontal disease were not associated with the occurrence of periodontitis. Higher levels of plaque and bleeding were observed for participants with parents reporting bad gingival health (76.2% and 46.9%) and deficient oral hygiene (79.5% and 47.3%). The perception of parents regarding gingival bleeding was correlated with higher bleeding detected clinically (P = 0.01; 50.1%).

CONCLUSIONS

The prevalence of periodontitis in individuals with Down syndrome is high and increases with age, even in the face of the parents' perception about their children's oral condition.

Systematic review versus structured critical analysis

Objective: This analysis discusses common problems with systematic reviews (SRs) and presents a novel solution, the structured critical analysis (SCA) that can be incorporated into a SR or used as an alternative literature review design.Methods: A cross-sectional survey of current SRs related to interdisciplinary restorative dentistry was obtained by evaluating 100 current SRs for their self-reported methodological quality and its effect on scientific validity.Results: The preferred reporting items for systematic reviews and meta-analyses protocol (PRISMA) was used in 99/100 SRs, but only 8/100 reported a low risk of bias. High statistical heterogeneity precluding meta-analysis was found in 44/100 SRs. Only 94 paragraphs/100 SRs provided critical analysis.Discussion: Significant problems were found with current SRs that can compromise their reliability as the premier level of evidence for clinical science research. The reader must be aware of these deficiencies to correctly interpret the SR and cannot rely on the format alone.

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.