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 Table of Contents  
REVIEW ARTICLE
Year : 2022  |  Volume : 17  |  Issue : 4  |  Page : 1013-1018

Down syndrome and its oral effects in saudi arabian region: A review of literature


Department of Preventive Science, College of Dentistry, Dar Uloom University, Riyadh, Saudi Arabia

Date of Submission24-Sep-2022
Date of Decision05-Oct-2022
Date of Acceptance10-Oct-2022
Date of Web Publication10-Feb-2023

Correspondence Address:
Dr. Fawzia Haif Alkahtani
Department of Preventive Science, College of Dentistry, Dar Uloom University, Riyadh 1422
Saudi Arabia
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jdmimsu.jdmimsu_433_22

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  Abstract 


The most prominent congenital syndrome is Down syndrome (DS). With the greatest number of births of all chromosomal disorders, it is the most well-known reason of physical as well as intellectual impairment. A comparatively elevated incidence of Down syndrome has been discovered in Saudi Arabia. Only few papers have been undertaken thus far describing the features of face and other oral features of Saudi Down syndrome subjects. To review the available literature on Down syndrome and it's oral effects in Saudi Arabia region. Down syndrome also described as trisomy of chromosome 21. It is a genetic autosomal inherited condition i.e non-sex chromosomal disorder that affects one in six hundred to one in two thousands live births in various populations and is marked by a deficit in physical and intellectual development. Due to the comparative elevated incidence of DS in Saudi Arabia—1 in every 554 live births—DS subjects were specifically chosen for this review of literature. There are now more people with DS as a result of the lowered mortality rate and rising incidence in Saudi Arabia population. The most noticeable craniofacial features are found in DS patients, along with other distinguishing physical and systemic manifestations. Midface deficit, prognathism of mandible, depressed position of nasal bridge, slanting of eyes, folds at the epicanthic region, condition of hypotelorism in ocular area, and strabismus constitute the documented craniofacial characteristics. Muscle hypotonia also affects the perioral muscles, which results in a lowering of the mouth's angle. A comparatively elevated incidence of Down syndrome has been discovered in Saudi Arabia. Only few papers have been undertaken thus far describing the features of face and other oral features of Saudi Down syndrome subjects. It can be concluded that individuals with Down syndrome in Saudi Arabia had a significantly higher incidence of facial as well as cranial features in comparison to the normal healthy counterparts. By using the search algorithms “(Down syndrome and dental caries, periodontal diseases), “(Down syndrome and deformity within oral structures), “(Down Syndrome and problems in occlusion and Craniofacial structures).”The researcher searched the Cochrane Central Systematic Reviews Registry, ISI Web of Science, and Medline without language restriction up to July 2022. Only few papers have been undertaken thus far describing the features of face and other oral features of Saudi Down syndrome subjects. It can be concluded that individuals with Down syndrome in Saudi Arabia had a significantly higher incidence of facial as well as cranial features in comparison to the normal healthy counterparts.

Keywords: Dental caries, down syndrome, oral effects


How to cite this article:
Alkahtani FH. Down syndrome and its oral effects in saudi arabian region: A review of literature. J Datta Meghe Inst Med Sci Univ 2022;17:1013-8

How to cite this URL:
Alkahtani FH. Down syndrome and its oral effects in saudi arabian region: A review of literature. J Datta Meghe Inst Med Sci Univ [serial online] 2022 [cited 2023 Mar 28];17:1013-8. Available from: http://www.journaldmims.com/text.asp?2022/17/4/1013/369504




  Introduction Top


The most prominent congenital syndrome is down syndrome (DS). With the greatest number of births of all chromosomal disorders, it is the most well-known reason of physical as well as intellectual impairment. Due to the comparatively elevated incidence of DS in Saudi Arabia –1 in every 554 live births –DS subjects were specifically chosen for this study. The average lifespan of these individuals has dramatically increased in recent years, as per the findings of Kumar et al.[1] and Horbelt.[2] There are now more people with DS as a result of the lowered mortality rate and rising incidence in Saudi Arabia's population.[3],[4],[5]

DS also described as trisomy of chromosome 21. It is a genetic autosomal inherited condition, i.e., nonsex chromosomal disorder that affects one in six hundred to one in two thousand live births in various populations and is marked by a deficit in physical and intellectual development. The most noticeable craniofacial features are found in DS patients, along with other distinguishing physical and systemic manifestations. Midface deficit, prognathism of the mandible, depressed position of the nasal bridge, slanting of eyes, folds at the epicanthic region, condition of hypotelorism in the ocular area, and strabismus constitute the documented craniofacial characteristics. Muscle hypotonia also affects the perioral muscles, which results in a lowering of the mouth's angle. Muscle hypotonia also affects the perioral muscles, which results in a lowering of the mouth's angle.[6],[7],[8],[9]

A comparatively elevated incidence of DS has been discovered in Saudi Arabia. Only a few papers have been undertaken thus far describing the features of the face and other oral features of Saudi DS participants. With a particular focus on the Saudi Arabian region, the goal of this literature study was to review the level of information on DS and its oral effects in the Saudi Arabia population.


  Search Strategy Top


By using the search algorithms “(Down syndrome and dental caries, periodontal diseases), “(Down syndrome and deformity within oral structures), “(Down Syndrome and problems in occlusion and Craniofacial structures).” The researcher searched the Cochrane Central Systematic Reviews Registry, ISI Web of Science, and Medline without language restriction up to July 2022. The investigator carefully reviewed the gathered material to determine its relevance and acceptability before included it in the final review composition. In order to generalize the findings to the Saudi population, an effort was also made to collect data specific to the Saudi Arabia region. Duplicate titles were removed from the acquired results after screening each of the titles that the search produced. The remaining papers' entire texts were retrieved, and they were checked for titles and abstracts. One independent researcher who was not a part of the review also examined the collected material to see whether it was appropriate.


  Some of the Important Oral and Maxillofacial Aspects of Down Syndrome are Top


Brachycephaly

The findings of a study conducted by Al-Shawaf in Saudi Arabia's population involving subjects with DS showed that the majority (more than 50%) of individuals suffering from Down's syndrome were found to suffer from brachycephaly. This clinical manifestation is less in percentage as stated by researcher Levinson et al. in 1955.[10] They analyzed the disparity in important clinical features in fifty individuals suffering from DS. The age of the study participants was between 4 years and 17 years. They discovered that 82% of the subjects with DS had brachycephaly along with flat occipital condition. However, the prevalence of sunken noses, condition of slanting eyes, and condition of epicanthic folds observed in the research in the Saudi Arab population was in accordance with the outcomes revealed by researchers Cohen and Wine and Levinson et al. According to researcher Levinson et al., strabismus affected 14% of their study populations. Though significantly lower than that described by Cohen and Winer[11] and slightly more than that described by Levinson et al.,[10] the strabismus seen in the research of DS patients in the Saudi Arabian population.[12],[13]

Incompetent lips

When the oral clinical features were evaluated in the study among DS patients in the Saudi Arabian population, incompetent lips were seen as oral symptoms in all Down's syndrome individuals. This finding exceeds what has previously been published in the literature as described by Asokan et al., 2008[14]; as well as Smith et al in 1976.[15] The relatively small nasopharynx and extremely large tonsils along with adenoids hold the mouth open. A similar justification for the protruding tongue and open mouth is the requirement to create an airway. In addition, the opening of the oral cavity is open as a result of the tongue's protrusion. The presence of breathing through the mouth, drooling of saliva from the corner of the mouth, condition of chapped lower lips, and angular cheilitis are all symptoms of this illness.[16],[17],[18],[19]

Infections of the respiratory tract and chronic infection of periodontium are caused by mouth breathing.[6] In addition, persistent mouth breathing can cause a drop in saliva production and mouth dryness. This lessens the natural cleaning that takes place in the mouth cavity and could help caries develop (Pilcher, 1998).[20]

Macroglossia

Clinical examination of the tongue in a study of Saudi citizens revealed that a large percentage of those with Down's syndrome have macroglossia, which is consistent with the discovery made by research carried out previously.

It has been stated that Levinson et al.[10] carried out a similar research and found that, only thirty percent of participants had macroglossia. Another research was carried out by Cohen and Winer, in which the dental features were analyzed in individuals suffering DS and they discovered that the prevalence of macroglossia was 11.3%, which really is lesser than the prevalence recorded in a study among the Saudi population. The discrepancy in sample sizes may be the cause of this. There is debate among authors as to whether macroglossia is a real or relative condition. According to some experts, macroglossia is a relative condition because of the limited oral cavity. According to some writers, insufficient lymphatic drainage is the root cause of macroglossia. A crenate shape of the tongue at the lateral surface of the tongue and an open bite might result from the pressure exerted by the enlarged tongue against the lower jaw as well as the dentition of the lower jaw.[21],[22],[23],[24]

In addition, speech issues are brought on by the protruding tongue. If the tongue sticks out of the mouth frequently, it could develop ulcers, have secondary infections, or even go into necrosis as reported by Neville et al.[25] A further consequence of severe macroglossia is airway blockage. Similar to this, a research done on people in Saudi Arabia found a significant prevalence of fissured tongues. This result is more than what other researchers have found. This might be as a result of this study's smaller sample size compared to their investigations.[26]

Fissured tongue

Age may play a role in the emergence of a condition of the fissured tongue. It has been shown that children suffering from Down's syndrome are likely to have fissures as well as cracks on their tongue as they get older according to Pilcher.[25]

Oster discovered the condition of fissured tongues in individuals of various ages, but he noticed that the occurrence rose with advancing age. Attributed to the variations in age range, which included patients aged 12–24, as opposed to younger patients in earlier studies, it is entirely feasible that the proportion of condition of fissured tongues in the research among DS patients in the Saudi Arabian population is greater than that reported in earlier studies. Fissured tongue is associated with indications that the disorder may be either an autosomal dominant or polygenic feature. In addition, local circumstances and age may promote to its growth. Halitosis can be brought on by food becoming stuck in these cracks. Regular cleaning of the tongue's dorsal surface can reduce this.[26],[30]

Palate

According to the literature, the percentage of Down's syndrome patients with high-arched palates varies from 33.3% to 74.0%. The findings of a study on the Saudi population are within this spectrum. Some scholars have explained that midface hypoplasia is the cause of this. Others hypothesized that although the hard palate's borders are excessively thick; the vault itself is actually of a regular height. However, this clinical manifestation was judged subjectively based solely on clinical observations in previous investigations, as well as the study among DS patients in the Saudi Arabian population.[31],[32]

Speech as well as mastication may be hampered by the restricted narrow palate, which may leave less room for the tongue in the oral cavity (Pilcher, 1998). In addition, high vault palates with a “V” shape could exhibit soft palate inadequacy and affect how well maxillary dentures stay in place (Desai, 1997). The orofacial signs seen in the study carried out in the Saudi population mostly agree with those found in earlier ones.[33]

Radiographic representation of craniofacial region

The observations of the study carried out regarding radiographic representations of craniofacial region among DS patients in the Saudi Arabian population are in line with what other researchers have previously reported. In this study, patients with Down's syndrome had radiographic evidence of calvarium thinning. This is consistent with Spitzer et al findings's. [34,35] The prolonged closure of the sutures of the cranium was not frequently observed in people with Down's syndrome. This radiographic observation was also noted by Spitzer et al [34,35] in their study population. The incomplete maturation of brains in patients suffering from Down's syndrome may be to blame for the postponed closure of the sutures of the cranium seen in the study among the Saudi Arabia population. Wide statures and reduction in thickness of the calvarium may increase the risk of fracture in case of a traumatic injury.[35]

Paranasal sinuses

In a study of DS patients in the Saudi Arabian community, it was found that there was a noticeably increased proportion of congenitally missing frontal air sinuses. Despite the age ranges of these research being different, this conclusion is backed by others. Spitzer and Robinson[34] reported similar results. Spitzer and Quilliam[36], however, found that 60% of study participants had hypoplasia in their frontal air sinuses. Normal people typically start to develop their frontal air sinuses around the age of six.

A complete lack of development of the maxillary sinus was not noted in a study carried out in the Saudi population. Spitzer and Robinson found this vital observation in only 3.6% of study participants. Therefore, it is not thought that down's syndrome frequently presents with a complete lack of development of the maxillary sinuses. It has been found that 3.4% of the study participants belonging to Down's syndrome category had hypoplastic maxillary sinuses. This result is consistent with Spitzer and Robinson's findings (1955).[34] The results of Spitzer and Quilliam (1958)[36], who revealed this observation in 45% of their study population, are in contrast.

Tooth agenesis

The frequency of tooth agenesis in male patients is greater than that of female patients. They are more commonly observed in the mandible as compared to the maxilla. It has been observed that the left side is more commonly involved than the right in people with DS, which is ten times more common than in the normal community. Maxillary and mandibular second premolars, maxillary lateral incisors, and central incisors of the mandible are the teeth most impacted by agenesis. First molars and canines hardly ever experience damage. Canines as well as second molars have shown signs of agenesis in both the maxillary arch and the mandible arch, whereas the first molar tooth has only shown signs of agenesis in the mandible.[35],[36],[37],[38]

Dental caries

The clinical supervision of people with DS is aided by the low occurrence of dental caries in these patients. In his study, Orner carried out the evaluation of dental caries in patients suffering from DS and compared them with that observed in their siblings. It was observed that patients suffering from DS had less dental caries than their siblings who were not impacted by the condition by less than one-third. Shapira et al. conducted a study and found that individuals suffering from DS who did not have dental caries had considerably lower  Streptococcus mutans Scientific Name Search than those who did. There are a number of things that are thought to be behind the low occurrence of dental decay.[39],[40] Details of some studies regarding oral health in children suffering from Down syndrome in [Table 1]
Table 1: Important features of some studies on Down Syndrome

Click here to view


Periodontal problems

Individuals suffering from DS are found to have more periodontal problems in comparison to their normal counterparts. Ages 6–15 are prime starting points for periodontal disease. Extreme tooth movement, which leaves no other option but extraction, is the most common issue by the mid-30s. Condition of marginal gingivitis, condition of severe periodontitis, condition of the recession of marginal gingiva, condition of development of periodontal pocket, condition of bone loss with pus discharge, condition of bifurcation and as well as trifurcation engagement in the molar region, condition of marked mobility of teeth, and frequent tooth loss, particularly in the mandibular anterior area, are among the conditions frequently observed in people with DS.[41]

Occlusion anomalies

The occlusion-related oral symptoms may need orthodontic or surgical treatment. Individuals suffering the condition of DS had a high prevalence of malocclusion cases in both deciduous dentition and permanent dentition than those without DS. The central, lateral incisors, and canine are the teeth that are affected the most commonly. A common symptom that can develop early in infancy and occasionally last the rest of a person's life is bruxism. It can eventually cause the supporting tissue to become overloaded and break down. “Transitory” bruxism is widespread in young children.[42]


  Conclusion Top


When compared to healthy controls in the same community, Saudi Down's syndrome patients had a significantly higher incidence of facial as well as cranial features.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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