Oral health condition and treatment needs of a group of Nigerian individuals with Down syndrome
Folakemi Oredugba
Objective: This study was carried out to determine the oral health condition and treatment needs of a group of individuals with Down syndrome in Nigeria. Method: Participants were examined for oral hygiene status, dental caries, malocclusion, hypoplasia, missing teeth, crowding and treatment needs. Findings were compared with controls across age group, sex and educational background of parents. Result: Participants with Down syndrome had poorer oral hygiene than controls, with no significant sex difference. Oral hygiene was similar in the lower age groups but deteriorated with age in the Down syndrome group. Conclusion: Individuals with Down syndrome in Nigeria have poorer oral health and more treatment needs than controls. They would benefit from frequent oral health assessment.
Oredugba FA. Oral health condition and treatment needs of a group of Nigerian individuals with Down syndrome. Down Syndrome Research and Practice. 2007;12(1);72-76.
doi:10.3104/reports.2022

Figure 1 | Teeth positions
Nine dental characteristics have been described in children with Down
syndrome[1]. These are macroglossia (enlarged tongue), fissured tongue,
underdeveloped maxilla (upper jaw), tongue thrusting, congenitally missing
teeth, malocclusion, high arch palate, increased salivation and microdontia
(smaller than normal teeth). One of the most striking features of the facial
characteristics of those with Down syndrome is the relative underdevelopment of
the middle third of the face and the consequent tendency to a Class III skeletal
base relationship[2]. There are deficits in the craniofacial anthropometric
pattern profile in Down syndrome: subnormal scores of head length, circumference
and the external canthal distance have been reported[3].
Periodontal disease is the most significant oral health problem in people with
Down syndrome. Manual dexterity difficulties may lead to oral hygiene problems.
Plaque and debris accumulation, gingivitis and periodontal disease are common.
Consequently, a large number of young people with Down syndrome lose their
permanent anterior teeth in their early teens. Children and young adults tend to
have fewer caries because of some associated conditions such as delayed eruption
of primary and permanent teeth, congenitally missing teeth and microdontia.
However, some may have increased risk of periodontal disease due to cariogenic
food choices and reduced food clearance from the mouth[4].
Literature is scarce on the oral health status of individuals with Down syndrome
in Nigeria. The objective of this study was to determine the oral health
condition of a group of individuals with Down syndrome and to compare with a
control group without Down syndrome in order to provide information on their
oral health needs in Nigeria.
Materials and Method
|
|
Study group |
Control |
Total |
|
number |
%
|
number |
% |
number |
% |
|
Age group (years) |
|
<6 |
6
|
14 |
7 |
16 |
13 |
15 |
|
6 - 10 |
11 |
26 |
9 |
21
|
20
|
23
|
|
11 - 15 |
9 |
21 |
9 |
21 |
18 |
21 |
| 16 - 20 |
7 |
16 |
15 |
35 |
22 |
26 |
| 20+ |
10 |
23 |
3 |
7 |
13 |
15 |
| Sex |
| Female |
21 |
49 |
20 |
47 |
41 |
48 |
| Male |
22 |
51 |
23 |
54 |
45 |
52 |
|
Family educational
background |
| High |
4 |
9 |
2 |
5 |
6 |
7 |
| Middle |
18 |
42 |
21 |
49 |
39 |
45 |
| Low |
21 |
49 |
20 |
46 |
41 |
48 |
| Total |
43 |
100 |
43 |
100 |
86 |
100 |
Table 1 | Demographic characteristics of the total population
|
|
Oral
hygiene |
|
Group |
Good |
Fair |
Poor |
Total |
| number |
% |
number |
% |
number |
% |
number |
|
Study |
10 |
23 |
16 |
37 |
17 |
40 |
43 |
|
Control |
30 |
70 |
10 |
23 |
3 |
7 |
43 |
|
Total |
40 |
47 |
26 |
30 |
20 |
23 |
86 |
p = < 0.05
Table 2 | Oral hygiene status of the total
population
Participants were individuals with Down syndrome drawn from four day
institutions for individuals with special needs in Lagos, Nigeria. Consent for
participation in the study was obtained from parents and head teachers of the
schools. Participants with Down syndrome were matched for age and sex with
controls who were students from two nearby schools and some members of staff of
those institutions. Questionnaires requesting socio-demographic information such
as name, age, sex and educational background and medical and dental history were
administered on each participant. Dental examination was carried out in the
respective institutions in daylight on return of the questionnaires. They were
examined for oral hygiene status, dental caries and malocclusion using the
Simplified Oral Hygiene Index score (OHI-S)[5], decayed, missing and filled
teeth (dmft/DMFT) index and Angle's classification according to the WHO Oral
Health Survey Basic Methods[6]. Educational background was determined by
classifying the educational level of the mother, and where she did not reside
with the child, that of the father, into:
- Upper class – Code 1 - those who attended tertiary institutions
- Middle class – Code 2 - those who had up to secondary school education
- Lower class – Code 3 - those who had primary school education or no education
Data were entered into a computer and analysed using the statistical software
Epi info version 6.04a[7]. Findings were compared across study and control
groups, age groups (< 6 years, 6-10 years, 11-15 years, 16-20 years and 20+
years), gender and educational background using descriptive statistics,
chi-square test and Kruskal-Wallis test for two groups where appropriate at p <
0.05 level of significance.
Results
A total of eighty-six participants were included in the study. They comprised 43
with Down syndrome and 43 controls without Down syndrome. There were 41 females
and 45 males with mean age 14.15±7.84 and the majority were from the middle and
low educational background (Table 1). A total of thirty (70%) individuals in the
control group had good oral hygiene, compared with 10 (23%) of the Down syndrome
group while 3(7%) of controls and 17(40%) of the Down syndrome group had poor
oral hygiene (p = 0.00) (Table 2). There was no significant difference in the
oral hygiene status between male and female and educational background.
At the lower age groups of <6 and 6-10 years, oral hygiene was similar, but at
the higher age groups of 11-15, 16-20 and 20+ years, oral hygiene was better in
the controls than in the Down syndrome group (Figures 2 and 3).
Figure 2 | Oral hygiene status of study (Down
syndrome) group according to age group

Figure 3 | Oral hygiene status of the controls
according to age group
The mean dmft of the Down syndrome group was 0.67 ± 2.0 while that of the
controls was 0.07 ± 0.3. (Table 3). The mean DMFT of the Down syndrome group was
0.23 ± 0.64 and 0.09 ± 0.29 in the controls (p > 0.05). There was also no
significant difference between male and female and educational background.
Twenty seven (63%) of the Down syndrome group had one or more missing teeth
(
Table 4). The teeth most frequently missing in the Down syndrome group were the
maxillary and mandibular left third molars in 6 (14%) subjects, followed by
maxillary and mandibular right third molars in 5 (12%) subjects. The maxillary
left lateral incisor was missing in 4 (9%) subjects while the maxillary right
lateral incisor and mandibular left lateral incisor and canine were missing in 3
(7%) subjects. The maxillary and mandibular right central incisors and canines,
mandibular right lateral incisor and mandibular left second premolar were
missing in 2 (5%) subjects. Other missing teeth include mandibular right and
left first premolars, mandibular right second premolar, maxillary and mandibular
left central incisors and mandibular right and left primary lateral incisors in
2% of the subjects.
Class I malocclusion was seen in 22 (51%) of the Down syndrome group and 41
(95%) of the controls, while class III malocclusion was seen in 20 (47%) of the
Down syndrome group and 2 (5%) of controls (Table 5) (p < 0.05). Other oral
conditions found in the Down syndrome group were crowding in 33%, gingivitis in
49%, Acute Necrotizing Ulcerative Gingivitis (ANUG) 5%, peg shaped lateral
incisor in 14%, and hypoplasia in 12%. The prevalence of hypoplasia was not
significantly different among the two groups (p > 0.05) (Table 6). Thirty three
(76%) of subjects in the Down syndrome group required Oral prophylaxis, compared
with thirteen (31%) of controls (Table 7). Ten (23%) Down syndrome and 6 (16%)
controls also required restorative treatment, while 5% and 11% of the Down
syndrome group required extractions and orthodontic treatment.
| |
dmf |
DMFT |
|
Group |
|
Study |
0.67±2.0 |
0.23±0.64 |
|
Control |
0.07±0.3 |
0.09±0.29 |
|
p |
> 0.05 |
> 0.05 |
|
Sex |
|
Female |
0.32±1.4 |
0.17±0.49 |
|
Male |
0.42±1.5 |
0.16±0.52 |
|
p
|
> 0.05 |
> 0.05 |
Table 3 | Mean decayed, missing and filled teeth (dmft/DMFT) scores of the total
population
| Group |
Missing teeth |
| + |
% |
- |
% |
Total |
|
Study |
27 |
63 |
16 |
37 |
43 |
|
Control |
0 |
0 |
43 |
100 |
43 |
|
Total |
27 |
31 |
59 |
69 |
86 |
Table 4 | Proportion of subjects with missing teeth in the total population
|
Group |
Class I |
Class II |
Class III |
|
| number |
% |
number |
% |
number |
% |
Total |
|
Study |
22 |
51 |
1 |
2 |
20 |
47 |
43 |
|
Control |
41 |
95 |
0 |
0 |
2 |
5 |
43 |
|
Total |
63 |
73 |
1 |
1 |
22 |
26 |
86 |
p < 0.05
Table 5 | Angle's classification
of occlusion in the total population
|
Oral conditions |
Study |
Control |
p |
|
number |
% |
number |
% |
| Gingivitis |
21 |
49 |
8 |
19 |
* |
| ANUG |
2 |
5 |
0 |
0 |
* |
| Crowding |
14 |
33 |
2 |
5 |
* |
| Spacing |
2 |
5 |
2 |
5 |
> 0.05 |
| Hypoplasia |
5 |
12 |
4 |
9 |
> 0.05 |
| Peg-shaped lateral incisor |
6 |
14 |
0 |
0 |
* |
| Missing teeth |
27 |
63 |
0 |
0 |
* |
* Significant p value
Table 6 | Other oral conditions in the total
population
|
Treatment need |
Study |
Control |
Total |
| number |
% |
number |
% |
number |
% |
|
Oral prophylaxis |
33 |
76 |
13 |
31 |
46 |
54 |
|
Restorations |
10 |
23 |
6 |
16 |
16 |
19 |
|
Extractions |
2 |
5 |
- |
- |
2 |
2 |
|
Orthodontic treatment |
5 |
12 |
- |
- |
5 |
6 |
Table 7 | Treatment needs of the subjects
according to groups
Discussion
Many individuals with Down syndrome participating in this study had poor oral
hygiene, a finding similar to that from previous studies[8]. The reasons for
this may include the reduced manual dexterity of the participants, joint laxity
(including the carpal joints) and the lack of comprehension of oral hygiene
needs due to mental difficulties. They therefore need help to carry out routine
oral hygiene measures. This seems clear in the lower age group of 10 years and
below in this study, where the oral hygiene status of the Down syndrome and
control groups is good, because they were being assisted by parents. As they
grow older, the assistance they receive from parents and care-givers begins to
reduce, because it is believed that an older child should not need help with
tooth brushing. Therefore oral hygiene becomes poorer with age as seen in this
study. Sasaki et al., reported 42% of individuals with Down syndrome with
gingivitis in their study[9]. This finding is close to the 49% seen in this
study, a significantly higher proportion than in the controls whose oral hygiene
improved with age. It should be noted that at the 6-10 year age group when
parental influence starts to reduce, there was no significant difference between
the Down syndrome and control groups. Lopez-Perez et al., also found that the
extent and severity of gingivitis and the extent of periodontitis were greater
in a group of persons with Down syndrome examined compared with controls[10].
Two subjects in the 20+ years age group presented with Acute Necrotizing
Ulcerative Gingivitis (ANUG). This condition has been widely reported in
individuals with Down syndrome[11]. It was suggested that systemic dysfunction
such as immunological deficiency in this population may predispose to oral
disease which may in turn aggravate systemic disease[12]. It was also suggested
that the secretion rates of IgA and IgG were diminished in individuals with Down
syndrome, and this could account for the high prevalence of recurrent infections
in target organs of the secretory immune systems[13]. It has been found that if
the dental hygienist can successfully teach the patient and the care giver
effective home care as part of the daily routine, gingival and periodontal
conditions can be controlled or eliminated[14]. Parents and care givers should
also be educated on the need to supervise tooth brushing for their wards with
special needs, irrespective of age. Oral hygiene is effective only if the
individuals with special needs are regularly helped by another person, which
emphasises the significance of care givers and/or family members for these
individuals[15].
The individuals with Down syndrome in this study had a higher prevalence of
dental caries than the controls though not significantly so. However, there were
more participants in the Down syndrome group with multiple carious lesions. The
findings in this study contrasts previous studies that reported a reduced rate
of dental caries in individuals with Down syndrome[16,17]. The lower prevalence
of dental caries observed in previous studies was attributed to higher salivary
pH, bicarbonate levels and streptococcus mutant counts, microdontia, hypodontia
and spaced dentition, delayed eruption and shallow fissures in premolars and
molars. Severe early childhood caries was seen in two children with Down
syndrome in this study. It was reported that children with Down syndrome are
more likely than typically developing children to be given a nursing bottle to
bed, weaned off bottle at an older age or given syrup-based medicines for
repeated infections because of swallowing problems[18].
The mean dmft/DMFT in this study is however still lower than the 0.7 of a
National Survey in Nigeria[19]. This may be attributable to the small
institutional population sample in this study. Most individuals with Down
syndrome in Nigeria are still kept at home and prevented from going to any
institution because of stigmatisation and low expectations among families.
Therefore, the sample may be biased towards individuals receiving a particular
type of care.
There was a high proportion of subjects with missing teeth in this study. More
than half of the Down syndrome group had one or more missing teeth. This is a
similar finding to many previous studies[20,21,22]. The teeth most frequently
missing in this study were the maxillary and mandibular left third molars
followed by the right third molars. The next frequently missing teeth were the
maxillary left lateral incisor followed by the right and mandibular lateral
incisor and canine. This contrasts with the finding from a previous study which
reported the maxillary lateral incisors to be most often missing followed by the
mandibular second premolar and maxillary second premolar[22,23]. It is however
in agreement with the study of Jensen et al., and Shapira et al.,[20,24] which
reported a higher prevalence of third molar agenesis in 74% of individuals with
Down syndrome older than 14 years.
The eruption sequence in Down syndrome can be irregular and the prevalence of
tooth agenesis is increased in the primary as well as in the permanent
dentition[20,25,26]. The clinical relevance of early recognition of hypodontia
is an adequate treatment plan for maintenance of primary teeth or early
orthodontic intervention[22].
The prevalence of Class I malocclusion in the Down syndrome group in this study
can be compared with the 46% reported by Scully and Cawson[11]. Nearly half of
the individuals with Down syndrome had Class III malocclusion compared with only
4.7% of the controls. This feature has been commonly reported in
literature[20,27]. This is a result of hypoplasia of the midface, and it is
reported that the craniofacial dysplasia becomes accentuated with age[27]. This midface dysplasia also contributes to the narrow maxilla and crowding seen in
individuals with Down syndrome, as demonstrated in this study in which there was
a significantly high proportion of subjects with Down syndrome with crowding of
the upper arch. The reported high prevalence of class III malocclusion in Down
syndrome, however, varies widely from 40% to 61%[28,20]. It has been
demonstrated that an individual with Down syndrome can be an excellent
orthodontic patient and should not be excluded from the patient population[29].
However, orthodontic prognosis may be poor because of learning disability, parafunctional habits and severe periodontal disease[11]. Peg shaped lateral
incisor was also a common finding in the Down syndrome group. It was suggested
that the slow rate of cell growth and a consequent reduced cell number which
characterise the syndrome may be responsible for the underdevelopment of the
upper jaw, the delayed dental development and the reduction in number and size
of teeth.
The major limitation of this study is the small number of participants. Only
four subjects refused examination and were therefore excluded from the study. It
should be noted that only a small proportion of individuals with Down syndrome
could be reached. Most of them still reside at home with no educational or
vocational plan from parents and guardians because of stigmatisation. Due to
their disability and an apparent lack of access to care, none of the
participants in this study had been to the dentist, though the lack of access to
care is not limited to those with Down syndrome. Healthier people in Nigeria
still attend dental facilities only when there is a dental problem[30]. The
treatment needs of individuals with Down syndrome in this study are more than
that of controls. Other studies have also found a higher level of dental care
needs in individuals with Down syndrome than in people without Down
syndrome[31]. Since most of the factors which contribute to periodontal disease
are present in these individuals – poor oral hygiene, malocclusion and deficient
immune system - the dentist has an obligation to prevent oral diseases through
appropriate activities and programmes that take the special needs of the
subjects into account[32]. Preventive oral hygiene and subgingival plaque
control has been emphasised and considered of particular importance for children
and young people with Down syndrome[9].
Conclusion
It can be concluded from this study that individuals with Down syndrome in
Nigeria have poorer oral health and more treatment needs than controls. They
would benefit from frequent oral health assessment.
Glossary
dmft - decayed, missing and filled teeth index (for primary
teeth)
DMFT - Decayed, Missing and Filled Teeth index (for permanent
teeth)
Maxillary - Upper jaw
Mandibular - Lower jaw
Malocclusion - Malalignment of teeth in the upper and lower
jaws
References
- Caldwell L. Dentistry and the Down's syndrome
patient. Journal of the Greater Houston Dental
Society. 2000;72:35-36.
- Lockart PB. Outpatient management of the
medically compromised patient. In: Dental Care of
the Medically Complex Patient. Elsevier Limited;
2005; p.46-119.
- Bagic I, Skrinjaric I, Verzak Z. Craniofacial
anthropometric pattern profile in Down syndrome.
International Journal of Paediatric Dentistry. 1999;
9 (Supplement 1):98.
- US Department of Health and Human Services.
Practical oral care for people with Down syndrome.
National Institute of Dental and Craniofacial
Research, Bethesda, MD; 2004.
- Greene JC, Vermillon JR. The Simplified Oral
Hygiene Index. Journal of American Dental
Association. 1964; 68:7-13.
- World Health Organization.
Oral Health Survey.
Basic Methods. 4th ed. Geneva, WHO; 1997.
- Dean AG, Dean JA, Coulombier D, Burton AH,
Brendel KA, Smith DC et al. Epi info Version 6.04a,
a word processing database, and statistics program
for public health on IBM-compatible microcomputers.
Atlanta, GA; Centers for Disease Control and
Prevention; 1996.
- Cichon P, Crawford L, Grimm WD. Early-onset
periodontitis associated with Down's syndrome – A
clinical interventional study. Annals of Periodontology. 1998;3:370-380.
- Sasaki Y, Sumi Y, Mitazaki Y, Hamachi T, Nakata
M. Periodontal management of an adolescent with Down
syndrome – a case report. International Journal of
Paediatric Dentistry. 2004;14: 127-135.
- Lopez-Perez R, Borges-Yanez SA,Jimenez-Garcia G,
Maupome G. Oral hygiene, gingivitis and
periodontitis in persons with Down syndrome. Special
Care Dentistry. 2002;22:214-220.
- Scully C, Cawson RA (2005). Disability.
Chromosomes and chromosomal anomalies. In: Medical
Problems in Dentistry. 5th Edition. Elsevier,
Churchill Livingstone; 2005, p.423-425.
- Hannequin M, Veyrune J-L. Significance of oral
health in persons with Down syndrome: a literature
review. Developmental Medicine and Child Neurology.
1999;41:275-283.
- Chaushu S, Yefenof E, Becker A, Shapira J,
Chaushu G. Severe impairment of secretory Ig
production in parotid saliva of Down syndrome
individuals. Journal of Dental Research. 2002;81:
308-312.
- Buxton R, Hunter J. Understanding Down's
syndrome: a review. Journal of Dental Hygiene.
1999;73:99-101.
- Tsami A, Pepelassi E, Gizani S, Komboli M,
Papagianoulis L, Mantzavinos Z. Oral hygiene and
periodontal treatment needs in young people with
special needs attending a special school in Greece.
Journal of Disability and Oral Health. 2004;5:57-64.
- Shapira J, Stabholz A. Caries levels,
streptococcus mutans counts, salivary pH and
periodontal treatment needs of adult Down syndrome
patients. Special Care Dentistry. 1991;11:248-251.
- Chan AR. Dental caries and periodontal disease
in Down syndrome patients. University of Toronto
Dental Journal. 1994;7:18-20.
- Randell DM, Harth S, Seow, WK. Preventive dental
health practices of non-institutionalized Down
syndrome children: a controlled study. Journal of
Clinical Pediatric Dentistry. 1992;16: 225-228.
- World Health Organization. Oral Health
Country/Area Profile Program: Nigeria. Oral Disease
Prevalence.[cited December 19, 2004]. Available
from:
www.who.collab.od.mah.se/index.
- Jensen CM, Cleall JF, Yip ASG. (1973).
Dentoalveolar morphology and developmental changes
in Down syndrome (trisomy 21). American Journal of
Orthodontics. 1973;64:607-618.
- Roger KH. Facial dysmorphism and syndrome
diagnosis. In: Roger KH, editor. Pediatric
orofacial medicine and pathology. London: Chapman &
Hall Medical Co; 1994, p.42-74.
- Acerbi AG, De Freitas C, De Magalhaes MHCG.
Prevalence of numeric anomalies in the permanent
dentition of patients with Down syndrome. Special
Care Dentistry. 2001;7:75-78.
- Fiske J, Shafik HH. Down's syndrome and oral
care. Dental Update. 2001;28:148-156.
- Shapira J, Chaushu S, Becker A. Prevalence of
tooth transposition, third molar agenesis and
maxillary canine impaction in individuals with Down
syndrome. Angle Orthodontist. 2000;70: 290-296.
- Roche AF, Barkla DH. The development of the
dentition in mongols. Australian Dental Journal.
1967;12:12-16.
- Russel BG, Kjaer I. Tooth agenesis in Down
syndrome. American Journal of Medical Genetics.
1995;55:466-471.
- Backman B, Grever-Sjolander AC, Holm AK,
Johansson I. Children with Down syndrome: oral
development and morphology after use of palatal
plates between 6 and 18 months of age. International
Journal of Paediatric Dentistry. 2003;13:327-335.
- Ronig R. A study of the teeth, dental arches and
malocclusion in mongoloid children. Masters Thesis,
University of Pittsburg; 1964.
- Desai SS. Orthodontic considerations in
individuals with Down syndrome: a case report. Angle
Orthodontist. 1999;69:85-88.
- Oredugba FA. Use of oral health care services
and oral findings in children with special needs in
Lagos, Nigeria. Special Care Dentistry. 2006;
26:59-65.
- Allison PJ, Hannequin M, Faulks, D. Dental care
access among individuals with Down syndrome. Special
Care Dentistry. 2000;20:28-34.
- Benzian H. Oral health and disability – the FDI
World Dental Federation perspective.[cited December
23, 2006]. Available from:
http://www.fdiworldental.org/public_health/pop_18iadh.htm
Received: 12 February 2007: Accepted 14 February
2007; Published online: 30 July 2007.