|Year : 2020 | Volume
| Issue : 2 | Page : 103-107
Dental caries experience and molar-incisor hypomineralisation in children: Pattern and severity
Titus Ayodeji Oyedele1, Nneka Maureen Chukwumah2, Yewande Isabella Adeyemo3
1 Department of Surgery, Ben Carson School of Medicine, Babcock University; Dental Department, Babcock University Teaching Hospital, Ilisan-Remo, Ogun State, Nigeria
2 Department of Preventive Dentistry, School of Dentistry, University of Benin; Department of Preventive Dentistry, University of Benin Teaching Hospital, Benin City, Edo State, Nigeria
3 Department of Child Dental Health, Faculty of Dentistry, College of Health Sciences, Bayero University, Kano/Aminu Kano Teaching Hospital, Kano, Kano State, Nigeria
|Date of Submission||30-Jan-2020|
|Date of Decision||09-Jul-2020|
|Date of Acceptance||22-Jul-2020|
|Date of Web Publication||9-Oct-2020|
Dr. Yewande Isabella Adeyemo
Department of Child Dental Health, Faculty of Dentistry, Bayero University, Kano, Kano State
Source of Support: None, Conflict of Interest: None
Context: While efforts have been directed at reducing caries prevalence and its consequences by increasing access to fluoride in developed countries, its prevalence in developing countries is still on the increase. This study determined caries experience, pattern and severity in children with and without molar-incisor hypomineralisation (MIH). Materials and Methods: This was a cross-sectional, hospital-based study in children aged 3–16 years whose parents/legal guardians consented to participate in the study. They were recruited when they presented at the Paediatric dental clinic in a tertiary institution in Nigeria where assessments of their caries status (using the Decayed, Missing and Filled Teeth/decayed, missing and filled teeth [DMFT/dmft] index), restorative status (F/f + D × 100) and caries severity (using the visible pulpal involvement, ulceration as a result of displaced tooth fragments, fistula and abscess [PUFA/pufa] index) were carried out. Results: A total number of 391 children participated in the study; 58.8% were female and 41.2% were male with their mean age being 9.99 (±0.18) years. The DMFT for the study population was 1.71, while dmft was 1.81 and 51.4% of the participants had MIH; generally, the restorative index for the population was low (3.2). Children with MIH had a higher number of decayed teeth compared to children without MIH (P = 0.001); Overall, DMFT was higher in MIH-affected children. There was a significant difference in teeth with pulpal involvement (P = 0.01) and teeth with abscess formation (P = 0.02) in children with MIH compared to children without. Conclusion: Children with MIH had higher prevalence of caries and was more severe, compared to children without MIH.
Keywords: Children, dental caries experience, dental caries severity, molar-incisor hypomineralisation, PUFA-index
|How to cite this article:|
Oyedele TA, Chukwumah NM, Adeyemo YI. Dental caries experience and molar-incisor hypomineralisation in children: Pattern and severity. Niger J Basic Clin Sci 2020;17:103-7
|How to cite this URL:|
Oyedele TA, Chukwumah NM, Adeyemo YI. Dental caries experience and molar-incisor hypomineralisation in children: Pattern and severity. Niger J Basic Clin Sci [serial online] 2020 [cited 2021 Jan 16];17:103-7. Available from: https://www.njbcs.net/text.asp?2020/17/2/103/297609
| Introduction|| |
Dental caries is a post-eruptive pathologic condition of external origin caused by bacteria that results in the dissolution of dental hard tissues with resultant formation of cavity and has been described as one of the most common disorders of humans. Caries results from an interplay of four factors – consumption of dietary sugars, presence of susceptible teeth, bacteria plaque and time. There are multiple factors that modulate the risk for caries. These include exposure to fluoride and preventive oral health behaviour of the individuals.
The prevalence of dental caries has been reported to be on the decrease over the years in developed countries due to increased access to fluorides, dental services and oral health education on a great part of the population. Oral diseases are still a major problem in most developing countries. In Africa, dental caries prevalence in pre-school children seems to be on the increase in countries or parts of countries where there is an increase in sugar intake, while it has remained low or decreased in countries where the poor economy restricts sugar intake. Recent studies have however shown that a significant portion of the same population still remains under treated and shows increase in caries experience. Despite the fact that dental caries is being influenced by many factors, its occurrence and severity may be increased by structural defect in the enamel such as molar-incisor hypomineralisation (MIH). A study by da Costa-Silva et al. showed that children with MIH had a higher caries experience in their permanent dentition than the general population.
MIH was first defined as hypomineralisation of systemic origin presenting as demarcated, qualitative defects of enamel of one to four first permanent molars frequently associated with affected incisors. It was further described as a developmental, qualitative enamel defect caused by reduced mineralisation of inorganic enamel components which leads to enamel discolouration and fractures of the affected teeth which, more recently, were noted to affect primary molars. The defective enamel can also be a locus of lowered resistance for caries because there is an increase in porosity and a consistently disorganised rod structure in the hypomineralised teeth. In affected teeth, where the porous enamel has chipped off, dental caries may develop more rapidly, especially in the 1st year period after eruption. This may lead to atypical cavities and sometimes complete coronal breakdown, requiring extensive treatment. Even with intact enamel, MIH-affected molars can be very sensitive to air, cold or warmth. Children often avoid brushing the sensitive molars that results in poor oral hygiene that in turn enhances caries formation.
The pattern and severity of dental caries varies between the primary and permanent dentition; within the primary dentition, the pattern also varies between first and second primary molars in both the mandibular and maxillary arches. Primary teeth are less susceptible to caries on their occlusal surfaces than the permanent molars, even though the first permanent molars erupt earlier. The difference in caries susceptibility is no doubt related to differences in morphology of the occlusal surfaces.
The caries formation in the hypomineralised enamel show atypical patterns and this may be attributed to the post-eruptive breakdown (PEB) of the enamel that characterizes the hypomineralised enamel. Mahoney et al. showed that there was a significant reduction in the hardness of hypomineralised enamel that predisposed them to PEB and in effect increased their susceptibility to caries development. At present, there is a dearth of information on the pattern and severity of dental caries on the hypomineralised enamel. Therefore, this study seeks to fill the gap in knowledge by determining the pattern and severity of caries in children affected with MIH compared with caries in children without MIH.
| Materials and Methods|| |
This was a cross-sectional study which involved children aged 3–16 years of age presenting at the Paediatric Dental Clinic of a tertiary hospital in South-South Nigeria. A total of 391 children participated in the study though the calculated sample size was 170 for each group of children (with and without MIH respectively) using the formula N = Z2 Pq/d2. The sample size was increased to 391 to account for a minimum of 10% attrition rate. The study participants who presented for routine check-up or treatment were examined and those who met the inclusion criteria were thoroughly briefed about the study. The inclusion criteria comprised children that were between 3 and 16 years of age whose parents/legal guardian consented voluntarily to their children participating in the study, children >8 years of age who gave their assent as well as children without amelogenesis imperfecta or other developmental enamel defects.
After signing the consent forms, their biodata including age and sex, was documented and thorough oral examinations were then carried out to assess for MIH, caries experience and caries severity. MIH was assessed based on European Academy of Paediatric Dentistry diagnostic criteria. Each permanent first molar and incisor teeth were examined for demarcated white, yellow or brown opacities. Opacities ≥2 mm in diameter were included in the study.
The caries status was assessed using the D/d = Decayed, M/m = Missing and F/f = Filled teeth (DMFT/dmft) index following the WHO criteria for the diagnosis of caries. The D/d (Decayed) component included carious teeth, filled teeth with recurrent decay, retained roots, defective fillings with caries, temporary fillings and filled teeth with another surface decayed. The M/m (Missing) component included only teeth missing due to caries. The F/f (Filled) component included teeth with restorations without decay and no secondary (recurrent) caries present, also teeth with crowns placed due to previous decay were included. Questions were asked to ascertain the reasons for a missing first permanent molar if it was extracted due to caries.
The DMFT/dmft was calculated as DMF = D/d + M/m + F/f with minimum score of zero, maximum score of 32 for permanent teeth and 20 for primary teeth.
Restorative index (RI) was also calculated using F/F + D × 100; Met Need Index (MNI) was calculated using M + F/DMF.
The caries severity was assessed, without the use of instruments or radiographs, using the PUFA index. P/p = Pulpal involvement recorded when the opening of the pulp chamber is visible or when the coronal tooth structures have been destroyed by the carious process and only roots or root fragments are left, U/u = Ulceration caused due to trauma from sharp pieces of tooth was recorded when sharp edges of dislocated tooth with pulpal involvement or root fragments have caused traumatic ulceration of the surrounding soft tissues, for example, tongue or buccal mucosa, F/f = Fistula was scored when a pus releasing sinus tract related to a tooth with pulpal involvement was present and A/a = Abscess was scored when a pus containing swelling related to a tooth with pulpal involvement was present in permanent and primary dentition, respectively. Calculation for PUFA/pufa = P/p + U/u + F/f + A/a with a minimum score of 0 and maximum score of 32 for permanent teeth and 20 for primary teeth.
Untreated caries-pufa ratio was also calculated using this formula (PUFA + pufa/D + d) × 100; this ratio helped to determine the percentage of teeth with untreated dental caries that have developed into dental infection.
This was done using the STATA (Statacorp. 2013. Stata Statistical Software:Release 13. College Station, Tx: Statacorp LP.). Descriptive analysis was done for discrete variables; Pearson Chi-square was used to determine the association between dependent and independent variables. P value was set at P ≤ 0.05.
Ethical approval for this study (ADM/E 22/A/VOL. VII/14705) was obtained from the Ethics and Research Committee of the hospital. Written informed consent was also obtained from parents/care givers/legal guardians who agreed for their wards to participate in the study, while assent was sought from study participants older than 8 years after being educated on the study and its objectives. There was no risk associated with this study except the discomfort of routine oral examination. This study was beneficial to the participants as adequate information and counsel about their oral health was given.
| Results|| |
A total number of 391 study participants were recruited for this study, 230 (58.8%) females and 161 (41.2%) males. The mean age of the study participants was 9.99 (±3.52) years; the DMFT/dmft for the study population was 1.71 and 1.81, respectively. A total number of 201 (51.4%) participants had MIH, while 190 (48.6%) did not have MIH, there was no statistically significant difference in the number of males with MIH (47.8%) and that of the females (53.9%).
Generally, the RI for the study population was low; for children with MIH, RI was 3.2% while that of children without MIH was 6.9%. Similarly, the MNI for the study population was low; 0.06 for children with MIH and 0.09 for children without MIH. In addition, the untreated dental caries that resulted in sequalae of dental caries and complication was higher in children with MIH (35.1) when compared to children without MIH (24.0).
[Table 1] shows the pattern of DMFT (DMFT/dmft) among children with MIH and children without MIH. Children with MIH had significantly more decayed permanent teeth when compared with children without MIH (P < 0.001), there were more missing permanent teeth in children without MIH compared to children with MIH and this was found to be statistically significant (P = 0.05). There was no significant difference in the number of filled teeth in both groups of children. Overall, the DMFT was higher in children with MIH when compared with children without MIH (1.87 vs 1.55). The mean dmfs for children with and without MIH in this study population was found to be 1.74 and 2.34, respectively, while for the general population, it was 2.03. The mean DMFS/dmfs was 3.52/1.74 for children with MIH as against 2.87/2.34 for children without MIH.
|Table 1: Pattern of Decayed, Missing and Filled Teeth/decayed, missing and filled teeth and Decayed, Missing and Filled Tooth Surfaces/decayed, missing and filled tooth surfaces among children with and without molar incisor hypomineralisation|
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Children with MIH were found to have a significant number of decayed teeth with severe consequences when compared to children without MIH using the PUFA/pufa index. There were significant differences in the teeth with pulpal involvement (P = 0.01) and teeth with abscess formation (P = 0.02) in children with MIH compared to children without MIH. The PUFA index in children with MIH was 0.72 compared to 0.40 in children without MIH. However, the difference in pufa index between children with MIH and children without MIH (0.19 vs 0.22) was less in the primary dentition, with a slightly less mean in children with MIH [Table 2].
|Table 2: The PUFA/pufa index in children with and without molar incisor hypomineralisation|
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[Table 3] shows the pattern of teeth affected by MIH and percentage of MIH-affected teeth with caries. These findings showed that the upper right (UR) and lower right (LR) quadrants have more first permanent molars being affected with MIH (43.0 vs. 47.8) when compared with upper left (UL) and lower left (LL) quadrants (38.9 vs. 42.7). In addition, more teeth were affected with MIH in the lower jaw compared with the upper jaw. However, there were more primary teeth affected with MIH in the UL and LL quadrants compared to UR and LR quadrants. For the anterior teeth, the upper central incisor teeth were more affected with MIH while the least affected anterior teeth with MIH were the lateral incisors.
|Table 3: Percentage of subjects with carious lesions according to tooth pattern|
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[Table 3] also shows the percentage of children with and without MIH who had dental caries affecting the index teeth. In the permanent first molars, there were more carious lesions recorded in the lower quadrants (LR 50.1%; LL 45.8%), compared to upper quadrants (UR 21.7%; UL 31.0%). This also applied to primary first molars (UR 14.3%, UL 17.9%; LR 18.2%, LL 21.0%).
| Discussion|| |
This was a hospital-based study that sought to compare the pattern and severity of dental caries among children with MIH and children without MIH. More females with dental caries were seen during the study period and the mean age of the study participants was 9.99 (±0.18) years. The DMFT/dmft for the study population was 1.72 and 1.81, respectively. There was a significant difference in the number of decayed and missing teeth between children with MIH and children without MIH. In addition, children with MIH had significantly higher PUFA/pufa index scores when compared to children without MIH.
Multiple studies have shown that children with MIH have a higher risk of developing dental caries compared to children without MIH but only a few studies have shown the pattern and severity of dental caries in children with MIH when compared to children without MIH. This present study tried to add to the body of existing knowledge by looking at the caries experience, pattern and severity of dental caries in children with MIH compared to those without MIH.
The number of children who presented at the study centre during the study period showed that MIH is a common occurrence and may be a major predisposing factor to development of dental caries as a higher percentage of these children seen had MIH. The number of decayed, missing and filled teeth was found to be higher in children with MIH when compared to children without MIH. This finding was similar to a study by Oyedele et al., who reported a higher DMFT among children with MIH compared to children without MIH. The higher DMFT may also be attributed to PEB of MIH affected teeth and poor oral hygiene, which has been reported to be common among children with MIH., This study also showed that children in the study population had a low RI and low MNI. The RI showed the restorative care received by these children while MNI is a measure of treatment received and this was very low when compared to a similar study by Denloye et al. This further buttresses the point that utilisation of oral health services is low even in the presence of increasing oral diseases. Furthermore, the untreated caries ratio for children with and without MIH, which was 34.1 and 24.0, respectively, showed that more than one third of decayed teeth in children with MIH had progressed to involve the pulp with further sequalae while only a quarter of decayed teeth in children without MIH progressed with further consequences. These values were however lower than those reported by Kamran et al.
The mean DMFS/dmfs pattern also reflected that children with MIH had more surfaces involved with dental caries when compared to children without MIH with the mean DMFS/dmfs being 3.52/1.95 for children with MIH as against 2.87/2.34 for children without MIH. This finding is important as dental caries development followed an atypical pattern in MIH-affected teeth. This results from the fact that children with MIH have a higher risk of developing carious lesions on the affected teeth and rapidly too since the mineral contents differ, favouring enamel demineralisation., Studies have shown that caries can develop in unusual surfaces in MIH-affected teeth when compared to teeth without MIH.
This study was able to establish a significant difference in the severity of dental caries in MIH-affected teeth when compared to teeth without MIH. MIH-affected teeth showed early pulpal involvement and the presence of abscess formation as a consequence of dental caries. The early pulpal involvement may have been due to PEB that could have encouraged rapid progression of dental caries. In addition, studies have shown that due to the disorganised enamel prisms and porosity of the enamel, infection easily progresses to involve the pulpal tissue and may be responsible for the formation of dental abscesses in caries involved teeth.
There was no significant difference in the number of teeth affected by MIH in both upper and lower jaws, but there was slightly higher occurrence of MIH in the UR and LR quadrants compared to UL and LL quadrants. This was in agreement with a previous study from the same country. There were more carious lesions in the lower jaw affecting the index teeth when compared to the upper jaw in both primary and permanent teeth. This difference in the caries distribution may be due to the severity of the MIH, which was not a scope of this study, and may also be due to effectiveness of oral hygiene measures, as some tend to brush their upper teeth more effectively than the lower teeth.
| Conclusion|| |
This study showed that children with MIH had more decayed teeth when compared with children without MIH. Furthermore, the caries experience of children with MIH had more severe consequences when compared with children without MIH. There were more pulpally involved and abscessed teeth in relation to the carious lesions in children who had MIH.
The occurrence and severity of the decayed teeth were likely potentiated by the structural defects in the enamel, in this case, MIH. These findings will help the clinicians pay more appropriate and adequate attention to children with MIH as well as encourage prophylaxis caries prevention methods.
We appreciate our highly cooperative study participants and their parents for their cooperation. The authors also appreciate the staff of the Paediatric Dental clinic where the study was done for providing an enabling environment.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3]