When hypomineralization affects permanent molars and
incisors, the condition is called molar incisor hypomineralization (MIH), which
can be observed in one or more of the permanent first molars with or without
hypomineralized lesions in permanent incisors.1, 2, 3, 4
Comparatively, the condition that affects primary second
molars is called deciduous molar hypomineralization (DMH) 1 or, more
recently, hypomineralized second primary molars (HSPM).5, 6 Such developmental lesions are usually
located on the occlusal third of the buccal surface or the incisal third of the
labial surface of the affected teeth, with a size of less than one third of the
affected surface.7
The hypomineralized teeth are a source of worry for dentists
and parents because of their deformed appearance and poor function in the
dental arch. MIH has therefore been described as a pandemic problem with a
global burden that requires monitoring by the entire health care community.8,9
The detrimental effects of hypomineralization on primary and permanent
dentition include rapid caries progression, the breakdown of teeth under
masticatory pressure, persistent hypersensitivity, and aesthetic concerns that
have a psycho-social impact.10,11 In addition, hypomineralization affects
the ability to treat these teeth because of the difficulty in bonding
restoration, the frequent failure of restorations, the need for multiple visits
to a dental clinic, and the difficulty in achieving good local anesthesia
before dental treatment, which subsequently leads to poor patient cooperation
and compliance12 and may result in losing these teeth. The definitive cause of hypomineralized
lesions is not well known, but it has been suggested that some predisposing
factors that occur prenatally, perinatally or postnatally play a role.
Recurrent upper respiratory tract infections, low birth weight, preterm birth,13
and the presence of dioxins in breast milk are common examples of
these factors.14 Some researchers claim that genetics is a factor.15
However, the cause could be a combination of more than one
factor.14
Since the development of the second primary molar (SPM)
starts before the development of permanent teeth, but both continue the process
simultaneously,1, 16 an injury that occurs in late pregnancy and
early perinatal period could affect both.5
The prevalence of MIH varies around the world. It could be as
low as 2.3% to as high as 40.2%.17-32 In Jordan, one study estimated
the prevalence of MIH as 17.6% in 2011,20 while another reported a
prevalence of 13.7% in 2020.21
Similarly, there was a great variation among studies that
reported the prevalence of hypomineralized second primary molars (HSPM) 33-41.
No studies in Jordan assessed the relationship between MIH
and HSPM in Jordanian children. Thus, the aim of this study was to examine if a
relationship exists, and whether or not HSPM can be considered a predictive
sign for the development of MIH.
A cross-sectional study was conducted on patients attending
the pediatric dental clinic at Prince Rashed Bin Al Hasan Military
hospital
(HSPM) or both. The diagnosis of the conditions was based on
the criteria adopted by the European Academy of Pediatric Dentistry (EAPD) in
2003,2 and adapted for diagnosing HSPM in 2008,1 then
revised in 2015.5,6 The severity of the lesion was classified as
mild or severe, in which the mild form showed demarcated patches of different
colors, while post-eruptive breakdown and atypical caries or restoration were
considered severe hypomineralization, based on modified (EAPD) system3,4 as
shown below.
The children were examined directly in the clinic by one
specialized pediatric dentists to ensure the reliability and repeatability,
with a mirror and a probe under good illumination in the dental office, with
the teeth dry (air blow was used to dry the teeth and gauze was used for
removing debris when present). The hypomineralized permanent first molars,
incisors, and second primary molars were then recorded. According to Weerheijm KL et al.,2 a child was
considered to have MIH if at least one of the permanent first molars was
affected by hypomineralization with or without affected incisors, and according
to Elfrink ME et al.,1 the
child was considered to have HSPM if at least one second primary molar was
hypomineralized. The teeth affected by hypomineralization were recorded.
Regarding the severity, the child was considered to have a
severe MIH if at least one severe lesion (according to the criteria mentioned
above) was found on the permanent first molars and/or incisors, and to have a
severe HSPM if there was at least one severe lesion on the second primary
molars. Otherwise, the case was recorded as a mild one.
The exclusion criteria included patients with dental
developmental defects such as amelogenesis imperfect, fluorosis, and deformed
teeth due to trauma or infection in the primary successors. In addition,
patients with grossly carious teeth, those undergoing orthodontic treatment,
and patients with systemic diseases or syndromes that may be associated with
defective or stained enamel, such as tetracycline staining in cystic fibrosis,
hyperbilirubinemia, or congenital porphyria, were excluded. Statistical Analysis
The descriptive statistics included some demographic
information and rates of MIH and HSPM in the
examined sample. Pearson χ 2 or Fisher’s
exact test were used to evaluate the association between the cooccurrence of
MIH and HSPM, and MIH and HSPM severity. Cramer’s V value estimated the
strength of these associations. The SPSS (version 23) software was used in the
analyses and a p-value of 0.05 or less was considered statistically
significant.
This study gained approval from the local ethical committee
of the Royal Medical Services in Jordan.
This study included 228 (125 female and 103 male) patients
whose ages ranged between 7 and 11 years, with an average of 8.5.
A total of 3648 teeth were examined for the presence of
hypomineralized lesions. These were 912 of each tooth type of concern, which
are: permanent first molar (PFM), permanent central incisors (PCI), permanent
lateral incisors (PLI) and second primary molars (SPM). Hypomineralization was
found in 1430 of them. However, the prevalence of hypomineralization in each
tooth type is shown in Table I.
Discussion
This study is
leading in exploring the relationship between MIH and HSPM in Jordanian
children. Both diseases share many similarities regarding their etiology,
mechanism of occurrence, and clinical presentation, but they are different in
respect to the teeth involved. MIH affects permanent first molars and permanent
incisors, while HSPM affects second primary molars. There is no clear consensus
on whether having HSPM necessitates the occurrence of MIH in the permanent
dentition.
The significant relationship results for the co-occurrence of
both diseases in many children of this study – about half (49.1%) of the
patients had both HSPM and MIH – are supported by other studies in the
literature. For instance, Mittal et al.
found that both diseases were concurrently occurring in 48% of the examined
patients,6P
which was very close to the percentage found in our study. Moreover, the
findings of P our study
reported that more than two thirds (74.7%) of the patients with HSPM had also
MIH, close to the findings of Negre-Barber et
al., which showed that among children with HSPM, 76.0% of them had MIH as
well.39P
However, this is higher than the findings of Ghanim P et al., who found that 39.6% of children with
HSPM suffered MIH, 40P
and much higher than many other studies.P 34P
, 36, 42
Alternatively, more than half (58.9%) of patients with MIH in
this study also had HSPM. This is higher than the findings of Negre-Barber et al. and Costa-Silva CM et al. (46.0% and 30.4%, respectively).39P ,42 P The higher percentage found
among this group of Jordanian children could be explained by genetic or
environmental factors. Nevertheless, HSPM can be considered a warning sign for
the prediction of development of MIH in any community, regardless of their genetic
or environmental background, as
reported by a number of studies.36P , 39, 42, 43
In the current study, two thirds (67.4%) of MIH cases were
severe, and severe HSPM cases formed 32.0% of the total cases of HSPM. Such
findings indicate a higher prevalence of severe manifestations of
hypomineralization in both primary and permanent teeth than that published by
Negre-Barber et al., who found the
percentage of severe cases was 28% and 8.3% in MIH and HSPM, respectively.39P These
rates P were supported
by others as well.36P
,37 Furthermore, the higher prevalence of severe HSPM,
which entails P a
higher prevalence of MIH – in many cases – leads to a higher number of
hypomineralized teeth that are prone, over time, to breakdown under normal
occlusal forces, which develop caries. A higher DMFT
(decayed, missing and filled teeth) index is the result of
that.31
Although there were almost equal numbers of mild cases among
males and females, severely hypomineralized SPM were more prevalent among
females. This contradicts the findings of Singh et al 48in India, Temilola et al34 in Nigeria and Halal et al 41 in Syria
that indicated no difference between males and females regarding the
distribution of the lesions.
Hence, the early diagnosis of hypomineralization is important
for preserving these teeth, particularly among high-risk children, such as
those with poor oral hygiene, limited access to dental care, and those from low
socio-economic communities.
Chronologically, it is known that the developmental periods
of permanent first molars, incisors, and primary second molars overlap, which
has led many researchers to claim that MIH and HSPM are related and occur
together,36,37,39 and therefore, they share a similar clinical
presentation, structural properties, and putative.44 Thus, if a risk
was imposed during the overlapping period of development, then the second
primary molar (SPM), first permanent molar (PFM) and permanent incisors (PI)
will be affected.13 The longer period of mineralization and slower
process of maturation of the PFM and PI in comparison to those of the SPM explain
the higher prevalence of MIH in comparison with HSPM.
The PFM is considered a cornerstone tooth in function and
occlusion, and its loss means that the masticatory function and occlusion will
be compromised. Unfortunately, in this study PFM was the most affected tooth by
hypomineralization, which is in line with other studies.45, 39, 46.
The early detection of MIH can preserve affected PFM. HSPM can serve as an
early alarm for parents and dentists to start a prevention program for a
hypomineralized PFM as early as it erupts. A good approach in dealing with
these hypomineralized PFMs was proposed by William V et al. which is a six-step protocol including risk assessment,
early diagnosis, remineralization and desensitization, prevention of caries and
posteruptive breakdown, restoration or extraction, and maintenance.47 Adjusting
dental programs as William V et al.
suggested will help in preserving hypomineralized primary and permanent teeth,
and ultimately the whole dentition.
Limitations
The study was a
dental clinic-based survey and conducted in a single hospital, so the results
cannot be applied to the general population. Furthermore, the sample size was
relatively small compared to studies with larger sample sizes. These limitations
could be overcome by conducting other studies with larger samples and from
different hospitals and schools so that the results can then represent the
general population of children in Jordan.
In conclusion, a significant co-occurrence between hypomineralized
second primary molar and molar incisor hypomineralization is noted. There are
biological and developmental changes around this age of childhood that
contribute to such incidences, which necessitate considering the occurrence of
hypomineralized second primary molars as a warning sign to expect a higher
possibility for the occurrence of molar incisor hypomineralization. This should
prepare parents to take early precautionary measures to protect their
children’s permanent teeth.
References
1. Elfrink ME, Ten Cate JM,
Jaddoe VW, Hofman A, Moll HA, Veerkamp JS. Deciduous molar hypomineralization and
molar incisor hypomineralization. J Dental Res 2012; 91(6):551-5
2. Weerheijm KL, Duggal M,
Mejare I, Papagiannoulis L, Koch G, Martens LC, Hallonsten AL. Judgment
criteria for molar incisor hypomineralisation (MIH) in epidemiologic studies: a
summary of the European meeting on MIH held in Athens, 2003. Eur J Paediatr
Dent 2003; 4(3):110-3
3. Kevrekidou A, Kosma I,
Arapostathis K, Kotsanos N. Molar incisor hypomineralization of eight and
14-year old children: prevalence, severity, and defect characteristics.
Paediatr Dent 2015;
37(5):455-61
4. Jeremias F, de Souza JF,
Silva CM, Cordeiro RC, Zuanon AC, Santos-Pinto L. Dental caries experience
and molar incisor hypomineralization. Acta Odontol Scand 2013;
71(3-4):870-6
5. Elfrink ME, Ghanim A,
Manton DJ, Weerheijm KL. Standardized studies on molar incisor
hypomineralization and hypomineralized second primary molars. Eur Arch Paediatr
Dent 2015; 16(3):247-55
6. Mittal LR, Chandak S,
Chandwani M, Singh P, Pimale J. Assessment of association between molar
incisor hypomineralization and hypomineralized second primary molar. J Int Soc Prev
Community Dent 2016; 6(1):34-38
7. Sidhu N, Wang Y, Barrett
E, Casas M. Prevalence and presentation patterns of enamel
hypomineralization among paediatric hospital dental patients in Toronto,
Canada: a crosssectional study. Eur Arch Paediatr Dent 2020; 21(2):263-70
8. Schwendicke F, Elhennawy
K, Reda S, Bekes K, Manton DJ, Krois J, Global burden of molar incisor
hypomineralization. J Dent 2018; 68(1):10-18
9. Schneider PM, Silva M. Endemic
molar incisor hypomineralization: a pandemic problem that requires monitoring
by the entire health care community. Curr Osteoporos Rep 2018;16(3):283-8
10. Lygidakis NA, Wong F,
Jalevik B, Vierrou A-M, Alaluusua S, Espeild
I. Best clinical practice guidance for clinicians dealing with children
presenting with molar incisor hypomineralisation: an EAPD Policy Document. Eur
Arch Paediatric Den 2010; 11(2):75-81
11. Kar S, Sakar S, Mukherjee
A. Prevalence and distribution of developmental defects of enamel in the
primary dentition of IVF children of west Bengal. J Clin Diagn Res 2014;
8(7):ZC73-6
12. Jalevik B, Klingberg GA.
Dental treatment, dental fear and behavior management problems in children with
severe enamel hypomineralization of their permanent first molars. Int J
Paediatr Dent 2002; 12(1):24-32
13. Aine L, Backstrom MC,
Maki R, Kuusela AL, Koivisto AM, Ikonen RS, Maki M. Enamel defects in
primary and permanent teeth of children born prematurely. J Oral Pathol Med
2000; 29(8):403-9
14. Beentjes VE, Weerheijm
KL, Groen HJ. Factors involved in the etiology of molar incisor
hypomineralization (MIH). Eur J Paediatr Dent 2002; 3(1):9-13
15. Vieira AR, Kup E. On
the etiology of molar incisor hypomineralization. Caries Res 2016;
50(2):166-9
16. Profitt W, Fields H.
Contemporary orthodontics. 3rd ed. St. Louis: Mosby Inc; 2000
17. Woullet E, Laisi S,
Salmela E, Ess A, Alaluusua S. Background factors of molar incisor
hypomineralization in a group of Finnish children. Acta Odontol Scand 2014;
72(8):963-9
18. Se MJSF, Ribeiro APD, dos
Santos-Pinto LAM, Loiola RC, Cordeiro RCL Cabral RN, Leal SC. Are
hypomineralized primary molars and canines associated with molar incisor
hypomineralization? Paediatr Dent 2017; 39(7):445-9
19. Zhao D, Dong B, Yu D, Ren
Q, Sun Y. The prevalence of molar incisor hypomineralization: evidence from 70 studies. Int J Paediatr Dent
2018; 28(2):170-9
20. Zawaideh FI, AlJundi SH,
AlJaljoli MH. Molar incisor hypomineralization: prevalence in Jordanian
children and clinical characteristics. Eur Arch Paediatr Dent 2011;
12(1):31-6
21. Hamdan MA, Ahmad EA, Al-Abdullah
M, Rajab LD. The prevalence and severity of molar incisor
hypomineralization among 8 year-old children in Amman, Jordan. Egyptian Dental
Journal 2020; 66(4):1989-97
22. Saber F, Waly N, Moheb D.
Prevalence of molar incisor hypomineralization in Egypt as measured by enamel
defect index a cross sectional study. Future Dental Journal 2018;
4(1):59-63
23. Parikh DR, Ganesh M,
Bhaskar V. Prevalence and characteristics of molar incisor
hypomineralization in the child population residing in Gandhinagar, Gujarat,
India. Eur Arch Paediatr Dent 2012; 13(1):21-26
24. Cho SY, Ki Y, Chu V. Molar
incisor hypomineralization in Hong Kong Chinese children. Int J Paediatr Dent
2008; 18(5):348-52
25. Buchgraber B, Kqiku L,
Ebeleseder KA. Molar incisor hypomineralization: proportion and severity in
primary public school children in Graz, Austria. Clin Oral Invest 2018;
22(2):757-62
26. Ng JJ, Eu OC, Nair R,
Hong CH. Prevalence of molar incisor hypomineralisation in Singaporean
children. Int J Paediatr Dent 2015; 25(2):73-8
27. Abdullah HE, Abuaffan AH,
Kemoli, AM. Molar incisor hypomineralization: prevalence, pattern and
distribution in Sudanese children. BMC Oral Health 2021; 6; 21(1):9
28. Yi X, Chen W, Liu M,
Zhang H, Hou W, Wang Y. Prevalence
of molar incisor hypomineralization in children aged 12 to 15 years in Beijing,
China. Clin Oral Investig 2021; 25(1):355-61
29. Koruyucu M, Ozel S, Tuna
EB. Prevalence and etiology of molar incisor hypomineralization in the city
of Istanbul. J Dent Sci 2018; 13(4):318-28
30. Davenport M, Welles AD,
Angelopoulou MV, Gonzalez C, Okunseri C, Barbeau L, et al. Prevalence of
molar incisor hypomineralization in Milwaukee, Wisconsin, USA: a pilot study.
Clin Cosmet Investig Dent 2019; 11(4):109-17
31. Jurlina D, Uzarevic Z,
Ivanesevic Z, Matijevic M. Prevalence of molar incisor hypomineralization
and caries in eight-year-old children in Croatia. Int J Environ Res Public Health 2020; 17(7):6358
32. Soviero V, Haubek D,
Trindade C, da Matta T, Poulsen S. Prevalence and distribution of
demarcated opacities and their sequelae in permanent first molars and incisors
in 7 to 13-year-old Brazilian children. Acta Odontol Scand 2009;
67(3):170-5
33. Elfrink ME, Veerkamp JS,
Aartman IH, Moll HA, Ten Cate JM. Validity of scoring caries and primary
molar hypomineralization (DMH) on intraoral photographs. Eur Arch Paediatr Dent
2009; 10(suppl 1):5-10
34. Temilola OD, Folayan MO,
Oyedele T. The prevalence and pattern of deciduous molar hypomineralization
and molar incisor hypomineralization in children from a suburban population in
Nigeria. BMC Oral Health 2015; 15(1):73-9
35. Owen ML, Ghanim A, Elsby
D, Manton D. Hypomineralized second primary molars:
prevalence, defect characteristics and
relationship with dental caries in Melbourne preschool
children. Aust Dent J 2018 63(1):72-80
36. Mittal N, Sharma BB. Hypomineralised
second primary molar: prevalence, defect characteristics and possible
association with molar incisor hypomineralisation in Indian children. Eur Arch
Paediatr Dent 2015; 16(6):441-7
37. Reyes MRT, Fatturi AL,
Menezes J, Fraiz FC, Assuncao LRDS, Souza JF. Demarcated opacity in primary
teeth increases the prevalence of molar incisor hypomineralization. Braz Oral
Res 2019 Aug; 15:33
38. Kuhnisch J, Heitmuller D,
Thiering E, Brockow I, Hoffmann U, Neumann C, HeinrichWeltzien R, Bauer CP, von
Berg A, Koletzko S, Garcia-Godoy F, Hickel R, Heinrich J. Proportion and
extent of manifestation of molar incisor hypomineralisation according to
different phenotypes. J Public Health Dent 2014; 74(1):42-9
39. Negre-Barber A,
Montiel-Company JM, Boronat-Catala M, Catala-Pizarro M, AlmerichSilla JM.
Hypomineralized second primary molars as predictor of MIH. Sci Rep 2016;
6(3):1-6
40. Ghanim A, Manton D,
Marino R, Morgan M, Bailey D. Prevalence of demarcated hypomineralised
defects in second primary molars in Iraqi children. Int. J Paediatr Dent 2013;
23(1):48-55
41. Halal F, Raslan N.
Prevalence of hypomineralized second primary molars (HSPM) in Syrian preschool
children. Eur Arch Paediatr Dent 2020; 21(6):711-7
42. Costa-Silva CM, de Paula
JS, Bovi Ambrosano GM, Mialhe FL. Influence of deciduous molar
hypomineralization on the development of molar incisor hypomineralization.
Braz. J Oral Sci 2013; 12(4):335-8
43. Garot E, Denis A, Delbos
Y, Manton D, Silva M, Rouas P. Are hypomineralised lesions on second
primary molars (HSPM) a predictive sign of molar incisor hypomineralisation
(MIH)? A systematic review and a meta-analysis. J Dent 2018; 72:8-13
44. Zakirulla M, Alasiri MA,
Alshahrani M, Alkhairy SI, Laheq MT, Althuqaiby AA et al. Prevalence of hypomineralization in second primary
molars (HSPM) in 7 to 10 year-old Saudi children. Journal of Research in
Medical and Dental Sciences 2020; 8(6):124-7
45. Mittal NP, Goyal A, Gauba
K, Kapur A. Molar incisor hypomineralization: prevalence and clinical
presentation in schoolchildren of the northern region of India. Eur Arch
Paediatr Dent 2014; 15(1):11-8
46. Kilinc G, Cetin M, Kose
B, Ellidokuz H. Hypomineralization in children living in Izmir city. Int
J Paediatr Dent 2019; 29(6):775-82
47. William V, Messer LB,
Burrow MF. Molar incisor hypomineralization: review and recommendation for
clinical management. Paediatr Dent 2006; 28(3):224-32
48. Singh R, Srivastava B,
Gupta N. Prevalence and pattern of Hypomineralized Second Primary Molar in
children in Delhi-NCR. Int J Clin Paediatr Dent 2020; 13(5):501-503.