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Table of Contents   
ORIGINAL RESEARCH  
Year : 2013  |  Volume : 24  |  Issue : 4  |  Page : 406-410
Prevalence of dentofacial abnormalities in children and adolescents with β-thalassaemia major


Department of Pedodontics and Preventive Dentistry, Ragas Dental College and Hospital, Chennai, Tamil Nadu, India

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Date of Submission17-Oct-2012
Date of Decision29-Nov-2012
Date of Acceptance28-Dec-2012
Date of Web Publication19-Sep-2013
 

   Abstract 

Background: β-thalassaemia major is a hereditary hemolytic anemia and the patients often experience growth retardation, protrusive maxilla, and depressed nasal bride leading to various degrees of malocclusion.
Aim: The purpose of this investigation is to find the prevalence of dentofacial abnormalities in β-thalassaemia major patients.
Subjects and Methods: Seventy-two patients between 6 and 18 years of age diagnosed with β-thalassaemia major were examined for extraoral abnormalities, malocclusion, oral hygiene, and dental caries. Data obtained were tabulated and statistically analyzed using Chi-square and paired t-test.
Results: Thirty-nine (54.2%) were males and 33 (45.8%) were females. Prominent extraoral abnormalities were found in 41 (56.9%) of the individuals. Study population predominantly had class I occlusion (59.7%) followed by class II occlusion (23.6%) and no class III occlusion. Mean oral hygiene index-simplified score was 2.43 ± 1.24, mean decayed missing filled teeth (DMFT) score was 7.10 ± 3.92, and deft was 5.68 ± 3.12.
Conclusion: Despite starting regular blood transfusion at an early age, β-thalassaemia major patients showed marked facial abnormalities. When compared with individuals with no systemic disease, oral hygiene status was similar, but the caries experience was higher in β-thalassaemia major patients. Therefore, emphasis to educate these patients in the prevention and control of dental caries and maintenance of good oral hygiene should be considered.

Keywords: Chipmunk facies, dental caries, oral hygiene, pale oral mucosa, saddle nose, thalassaemia major

How to cite this article:
Elangovan A, Mungara J, Joseph E, Guptha V. Prevalence of dentofacial abnormalities in children and adolescents with β-thalassaemia major. Indian J Dent Res 2013;24:406-10

How to cite this URL:
Elangovan A, Mungara J, Joseph E, Guptha V. Prevalence of dentofacial abnormalities in children and adolescents with β-thalassaemia major. Indian J Dent Res [serial online] 2013 [cited 2023 Mar 27];24:406-10. Available from: https://www.ijdr.in/text.asp?2013/24/4/406/118360
Thalassaemias are autosomal recessive gene disorder caused by impaired synthesis of one or more globin chains of hemoglobin. The disease was first recognized clinically in the year 1925 by Dr. Thomas Cooley, who described a syndrome of anemia with microcytic erythrocytes. The impairment alters production of hemoglobin which causes varying degrees of anemia that can range from significant to life-threatening. [1] These hereditary anemias are caused by mutations on chromosome 16 that encodes α-globin genes and on chromosome 11 which encodes the γ, δ, and β-globin genes. This defect affects either α or β polypeptide chains of the globin portion of the hemoglobin molecule. Based on the globin chain affected, the disease may be classified as α-thalassaemia or β-thalassaemia. Based on clinical and genetic entities, thalassaemias are classified as homozygous, heterozygous, or compound heterozygous. Although the heterozygous form of β-thalassaemia disease (thalassaemia minor) is mild with minimum clinical expression, the homozygous form of β-thalassaemia (thalassaemia major) exhibits the most severe clinical symptoms with marked oro-facial defects. Rarely, a less severe form called thalassaemia intermedia also occurs. [2]

There are about 240 million carriers of β-thalassaemia worldwide and in India alone, the number is approximately 30 million with a mean prevalence of 3.3%. [3] The homozygous form of β-thalassaemia is transfusion dependent. The first clinical manifestation of the disease occurs at 4-6 months of life. Affected infants are severely anemic, fail to thrive, and become progressively paler. Feeding problems, diarrhea, recurrent fever, spontaneous fractures, bleeding, susceptibility to infections, hepatosplenomegaly, and retardation of growth are some of the commonly presenting symptoms. [1] Also patients with β-thalassaemia have been found to have lower bone mineral density. [4] It has been reported in the literature that the major facial change in thalassaemic patients is the prominent cheek bones, enlargement of maxilla caused by erythroid hyperplasia with depression of the bridge of the nose. These result in the characteristic facial appearance called as "Chipmunk faces or Rodent faces." [5] Dental and facial abnormalities include spacing of teeth, forward drift of maxillary incisors, anterior open bite, protrusion of maxilla, occlusal abnormalities, and saddle nose. Also, the pneumatization of maxillary antrum is delayed in the affected individuals. [6] Although the prevalence and severity of oro-facial anomalies have been documented to be associated with β-thalassaemia major, only limited data are available about the oral health status of thalassaemic children. Although one study showed that there is no association between gingivitis, periodontal disease, and β-thalassaemia major, [7] few studies have shown higher prevalence of periodontal problems as well as dental caries in patients with β-thalassaemia major. [8],[9] Also, not much data are available regarding the dental and facial abnormalities in children with β-thalassaemia from the Indian sub-continent. With this background, this study was aimed to examine the prevalence of facial and dental abnormalities in children with β-thalassaemia major and also to find out the level of oral hygiene and dental caries experience in these children.


   Subjects and Methods Top


This cross-sectional study was conducted initially on 78 patients from various parts of the state of Tamil nadu, India who were registered in the Thalassaemia Welfare Association, Chennai diagnosed with β-thalassaemia major after obtaining permission from the Thalassaemia Welfare Association and approval from the Institutional Review Board (IRB) of Ragas Dental College and Hospital, Chennai (Ref. No. 201206IRB36).

The participants of this study were receiving regular blood transfusion every 3-4 weeks in the T.T. Krishnemachari (TTK) Blood Bank affiliated with the Voluntary Health Services and thalassaemia welfare association. Patients above 18 years of age were excluded from the study and finally 72 patients were included whose participation in the study was voluntary. The present experiment was undertaken with the written consent obtained from all the parents of each participant prior to the commencement of the study. A complete medical history of all the subjects and lateral cephalometric radiographs that were already taken for diagnostic purposes were obtained from the medical records. A single trained and calibrated examiner performed comprehensive examination with the assistance of one recorder for recording extraoral abnormalities, oral hygiene status, and dental caries while making the patients sit on a chair under visible light using mouth mirror and community periodontal index (CPI) probe. Oral hygiene conditions were recorded using oral hygiene index-simplified (OHI-S) [10] and modification given by Miglani et al. for primary dentition. [11] Dental caries was diagnosed and recorded by visual examination utilizing the criteria recommended by the World Health Organization and documented using the tooth description code (DMFT/deft). [12]

Descriptive statistics including mean and standard deviation for OHI-S and DMFT/deft were determined for all the subjects who were examined. Prevalence of dentofacial abnormalities and malocclusion was also determined (%). Data were statistically analyzed using Chi-square test and paired t-test using SPSS software version 15. A P < 0.05 was considered to be significant.


   Reproducibility Top


Twelve subjects were randomly selected and re-examined by the same examiner to know the intra-examiner variability. The OHI-S and presence/absence of caries were re-examined and recorded before calculation. There was no significant difference between mean OHI-S scores of first (1.16) and second time (1.25) assessments (P = 0.33). Kappa value for the presence or absence of caries was found to be 0.88.


   Results Top


Out of the 72 β-thalassaemia major patients examined, 39 (54.2%) were males and 33 (45.8%) were females. [Table 1] shows the demographic data of the study population. The age range of the thalassaemic patients was between 5 and 18 years. Of the 72 patients examined, diagnostic lateral cephalograms were available for 62 patients. Four of them presented with "hair on end" calvarium. [Table 2] shows the prevalence of dentofacial abnormalities found in the study population. [Figure 1] shows chipmunk facial appearance and [Figure 2] shows saddle nose appearance of β-thalassaemia major patients participated in this study.
Table 1: Demographic data of the study population

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Table 2: Prevalence of dento-facial findings of the study population

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Figure 1: A thalassaemic patient showing characteristic chipmunk facial appearance

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Figure 2: Saddle nose appearance of a patient with β-thalaessemia major

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In this study, 43 (59.7%) patients had Angle's class I molar relationship, 17 (23.6%) had Angle's class II molar relation, and none of the patients had Angle's class III molar relation. In 12 (16.7%) patients, the molar relationship could not be assessed due to partially erupted I molars. At least, one form of malalignment of teeth was seen in 14 of the patients examined [Figure 3].
Figure 3: Severe crowding of teeth in a subject of the study

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The OHI-S index revealed that 4 individuals had good oral hygiene, 58 of them had fair oral hygiene and only 10 of the study population had a poor oral hygiene status [Figure 4]. The mean scores of OHI-S, deft, and DMFT are given in [Table 3]. No significant difference in OHI-S scores was found between males and females (P = 0.074). There was a statistically significant difference in caries experience between primary dentition and permanent dentition (P = 0.018) with higher caries experience in the permanent dentition of these patients. There was no statistically significant difference in the caries experience of both primary and permanent dentition among males and females (P > 0.05).
Table 3: Mean oral hygiene index-simplified and caries scores of primary and permanent dentition

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Figure 4: Distribution of the sample based on oral hygiene

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   Discussion Top


Thalassaemia poses a great challenge to health-related quality of the life of children. A good knowledge about the oro-facial and other oral manifestations of thalassaemic patients would be essential to develop a more suitable clinical, psychological, and social support that might help in improving treatment outcomes of these patients. It is important to know and understand the dentofacial changes associated with these patients and their implications for orthodontic treatment. [2] With only limited research and literature available in this area, this study is an attempt to find out both the prevalence of facial abnormalities and intraoral findings of children and adolescents affected with β-thalassaemia major.

Patients suffering from β-thalassaemia major show great clinical variability in the systemic signs and symptoms with which they present. [13] Because of the severe anemia they suffer in early childhood, bony changes, retardation of growth, and splenomegaly may occur. It has been stated that the effects of thalassaemia on bones depend on the severity of anemia, patient's age, duration of clinical symptoms, and the timing of both therapeutic blood transfusion and splenectomy. [14] The transfusion therapy may diminish or indeed, prevent development of bony abnormalities in growing patients. [15] All the participants of this study started with blood transfusion therapy below 1 year of age and are on regular transfusion since then. This might be the reason for very minimal characteristic "Hair-on-end" appearance of the calvarium on lateral cephalograms of thalassaemic patients.

In this study, β-thalassaemia major patients presented with a wide variety of dentofacial abnormalities which has been reported previously. [16] Higher rates of malocclusion were reported among thalassaemic subjects by few studies, [15],[17] but by early hypertransfusion treatment policy, these changes are now controlled in younger patients. In this sample, the "chipmunk" or "rodent"-like facial appearance was found to be present among 30 of the affected patients. This is due to the fact that, when ineffective erythropoiesis damages the red blood cells (RBC) leading to severe anemia, the body responds by increasing the production of RBC, consequently causing expansion of bone marrow up to 15-30 times higher than the normal amount. The bone marrow expansion causes hyperplasia of the alveolar process of the maxilla at the expense of the sinus's normal volume. This in turn leads to the occurrence of maxillary anterior teeth protrusion, spacing between upper anteriors, anterior open bite, etc. [18] The skull and face deformities are closely related to the patient's age, the intensity of anemia, and the beginning time of treatment. Patients who receive inadequate blood transfusion in childhood will have more bony changes in adolescence.

In this study, patients with β-thalassaemia major predominantly had class I occlusion (59.7%) followed by class II occlusion (23.6%). Similar findings have been reported in the literature. [19] It has been stated that bone marrow hyperplasia caused by rapid red cell turnover results in the changes in bony structure in patients with β-thalassaemia. The hyperplasia of bone marrow in the maxilla exceeds that of the mandible, which may help to explain the absence of Angle's class III occlusion in these patients. [20] Also none of the patients included in this study had a medical history of bone marrow transplantation procedures prior to the study date.

The occurrence of pale oral mucosa in 16 of the 72 examined thalassaemic patients in this study may due to bilirubin produced as a result of destruction of RBC which can be reduced by regular and repeated blood transfusion to preserve the hemoglobin amount in an appropriate level (at least 10 g/dl). [21] In this study, majority of the patients had a fair oral hygiene, only 10 of the subjects had poor oral hygiene. This finding indicates that gingivitis/periodontitis is not an essential intraoral finding among β-thalassaemia major patients. This result is in agreement with the few other studies. [15],[22] These studies have reported that many of the β-thalassaemia major patients have a fair to good oral hygiene and are not associated with increased levels of gingivitis or periodontitis. Although the studies on healthy same age grouped children conducted in the same location where this study was conducted showed less caries scores, [23],[24] the present study showed higher caries scores among β-thalassaemia major patients. Our findings are supported by few findings in the past which showed that patients with β-thalassaemia had significantly higher caries scores as compared to the controls. [7],[25],[26] On the contrary, same incidence of dental caries among β-thalassaemia patients and their controls has also been reported in the literature. [27] It has been stated that the salivary Streptococcus mutans level was found to be significantly higher in these patients as compared to their controls. [22] A high deft/DMFT score suggests that these patients are in need of restorative dental care. The findings of this study highlight the dental treatment needs of this population. Parents of these patients pre-occupied with the life-threatening problem neglect basic dental care and visit the dentist only when their child has toothache. As infection is one of the major concerns in such patients, oral health prevention is of prime importance; a rigorous preventive regime must be implemented, including oral hygiene instructions, diet counseling, and appropriate use of topical fluoride and fissure sealants. However, further studies with larger sample and controls would give a better picture about the dental problems of children affected with β-thalassaemia major.


   Conclusion Top


With improved treatment measures, more children suffering with β-thalassaemia now survive into adulthood and it is important to improve their quality of life, for which good dental health and a high standard of dental care contributes significantly. A unified approach to dental care is essential, including close liaison with the hematologists and pediatricians. The dentist, especially the pediatric dentist plays a vital role to educate such patients and parents regarding the prevention of dental caries and the importance to maintain good oral hygiene.

This study shows:

  • The presence of a variety of dentofacial abnormalities in patients with β-thalassaemia major who are in their first and second decades of life.
  • The oral hygiene status of β-thalassaemia major patients is comparable to that of healthy individuals but these patients have a higher caries experience than the general population.

   Acknowledgment Top


The authors would like to thank Mr. Ganesan, Thalassaemia Welfare Association, Chennai for his help in conducting the study.

 
   References Top

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2.Abu Alhaija ES, Hattab FN, Al-Omari MA. Cephalometric measurement and facial deformity in subjects with β Thalassemia major. Eur J Orthod 2002;24:9-19.  Back to cited text no. 2
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3.Manglani M, Lokeshwar MR, Vani VG, Bhatia N, Mhaskar V. 'NESTROFT' - An effective screening test for beta thalassemia trait. Indian Pediatr 1997;34:702-7.  Back to cited text no. 3
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4.Pirinççioðlu AG, Akpolat V, Köksal O, Haspolat K, Söker M. Bone mineral density in children with beta-thalassemia major in Diyarbakir. Bone 2011;49:819-23.  Back to cited text no. 4
    
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8.Parkin SF. Dental treatment for children with thalassemia. Oral Surg Oral Med Oral Pathol 1968;25:12-8.  Back to cited text no. 8
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9.Leonardi R, Verzì P, Caltabiano M. Epidemiological survey of the prevalence of dental caries in young thalassemia major patients. Stomatol Mediterr 1990;10:133-6.  Back to cited text no. 9
    
10.Greene JC, Vermillion JR. The simplified oral hygiene index. J Am Dent Assoc 1964;68:7-13.  Back to cited text no. 10
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11.Miglani DC, Beal JF, James PM, Behari SA. The assessment of dental cleanliness status of the primary dentition using a modification of the simplified oral hygiene index (OHIS-M). J Indian Dent Assoc 1973;45:385-8.  Back to cited text no. 11
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12.World health organization. Oral Health Survey, Basic Methods. 4 th ed, Chapter 5. Geneva: World Health Organization; 1997. p. 39-45.  Back to cited text no. 12
    
13.Al-Wahadni A, Qudeimat MA, Al-Omari M. Dental arch morphological and dimensional characteristics in Jordanian children and young adults with beta-thalassaemia major. Int J Paediatr Dent 2005;15:98-104.  Back to cited text no. 13
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14.Gupta SK, Sharma M, Tyagi S, Pati HP. Transfusion-induced hemoglobinopathy in patients of beta-thalassemia major. Indian J Pathol Microbiol 2011;54:609-11.  Back to cited text no. 14
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15.Kaplan RI, Werther R, Castano FA. Dental and oral findings in cooley's anemia: A study of fifty cases. Ann N Y Acad Sci 1964;119:664-6.  Back to cited text no. 15
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16.Drew SJ, Sachs SA. Management of the thalassemia-induced skeletal facial deformity: Case reports and review of the literature. J Oral Maxillofac Surg 1997;55:1331-9.  Back to cited text no. 16
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17.De Mattia D, Pettini PL, Sabato V, Rubini G, Laforgia A, Schettini F. Oromaxillofacial changes in thalassemia major. Minerva Pediatr 1996;48:11-20.  Back to cited text no. 17
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18.Wonke B. Bone disease in with β-thalassaemia major. Br J Haematol 1998;103:897-901.  Back to cited text no. 18
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19.Salehi MR, Farhud DD, Tohidast TZ, Sahebjamee M. Prevalence of orofacial complications in Iranian patients with β-thalassaemia major. Iranian J Publ Health 2007;36:43-6.  Back to cited text no. 19
    
20.Pusaksrikit S, Isarangkura P, Hathirat P. Occlusion of the teeth in thalassemic patients. Birth Defects Orig Artic Ser 1987;23:429-33.  Back to cited text no. 20
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21.Baþsimitçi S, Yücel-Eroðlu E, Akalar M. Effects of thalassaemia major on components of the craniofacial complex. Br J Orthod 1996;23:157-62.  Back to cited text no. 21
    
22.Lugliè PF, Campus G, Deiola C, Mela MG, Gallisai D. Oral condition, chemistry of saliva, and salivary levels of Streptococcus mutans in thalassemic patients. Clin Oral Investig 2002;6:223-6.  Back to cited text no. 22
    
23.Mahesh Kumar P, Joseph T, Varma RB, Jayanthi M. Oral health status of 5 years and 12 years school going children in Chennai city - An epidemiological study. J Indian Soc Pedod Prev Dent 2005;23:17-22.  Back to cited text no. 23
    
24.Saravanan S, Kalyani V, Vijayarani MP, Jayakodi P, Felix J, Arunmozhi P, et al. Caries prevalence and treatment needs of rural school children in Chidambaram Taluk, Tamil Nadu, South India. Indian J Dent Res 2008;19:186-90.  Back to cited text no. 24
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26.Mashid M, Mehdizadeh M, Zamani G. Orodental complications in patients with major Beta-thalassemia. Dent Res J 2008;5:17-20.  Back to cited text no. 26
    
27.Scutellari PN, Orzincolo C, Andraghetti D, Gamberini MR. Anomalies of the masticatory apparatus in beta-thalassemia. The present status after transfusion and iron-chelating therapy. Radiol Med 1994;87:389-96.  Back to cited text no. 27
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Correspondence Address:
Arun Elangovan
Department of Pedodontics and Preventive Dentistry, Ragas Dental College and Hospital, Chennai, Tamil Nadu
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0970-9290.118360

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    Figures

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    Tables

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