|Year : 2018 | Volume
| Issue : 1 | Page : 20-27
The distribution of orofacial clefts at the medunsa oral health centre, cleft clinic
Prashantha Moodley, Mosimane Peter Silas Sethusa, Mohamed Imran Khan
Department of Orthodontics, Sefako Makgatho Health Sciences University, Pretoria, South Africa
|Date of Web Publication||8-Feb-2018|
Dr. Prashantha Moodley
850 Veda Lane, Unit 46 Montuscan Villas, Montana Pretoria
Source of Support: None, Conflict of Interest: None
Background and Objectives: The prevalence of orofacial clefts shows considerable international variation. African studies show a low prevalence of these congenital malformations and this could be due to poor record keeping and a lack of data capturing. The aim of this study was to create an electronic database and to perform an epidemiological survey of all orofacial clefts seen at the MOHC, Cleft Clinic from its inception in 2003 to December 2014. Materials and Methods: Records of 383 patients were obtained and data transferred into Microsoft Access. Gender, ethnicity, site of cleft lip, and palate, as well as a family history of cleft lip and palate were recorded. Data analysis was primarily of a descriptive nature and categorical data was summarized by frequency counts and percentage calculations. Results: Forty seven percent of patients presented with unilateral clefts, 23% presented with bilateral, and 30% presented with clefts of the palate. Clefts on the left side accounted for 56.4% and on the right side 43.58%, thus making clefts on the left side more common. Clefts affecting the lip and palate accounted for 45.8%, those affecting the lip 24.2% and those affecting only the palate 30%. The most common cleft was a bilateral complete cleft and it was found in 15.3% of females and 16.78% of males. Facial clefts were found in 2.4% of patients. A positive family history of orofacial clefts was found in 5.48% with cousins being the most affected. Black patients accounted for 94.52% of those affected. Females were more affected than males, and in both genders the most common cleft identified was that of a bilateral complete cleft. Conclusion: An electronic epidemiological database of orofacial clefts at the MOHC has been recorded.
Keywords: Cleft lip and palate, epidemiology, facial clefts
|How to cite this article:|
Moodley P, Sethusa MP, Khan MI. The distribution of orofacial clefts at the medunsa oral health centre, cleft clinic. J Cleft Lip Palate Craniofac Anomal 2018;5:20-7
|How to cite this URL:|
Moodley P, Sethusa MP, Khan MI. The distribution of orofacial clefts at the medunsa oral health centre, cleft clinic. J Cleft Lip Palate Craniofac Anomal [serial online] 2018 [cited 2019 May 24];5:20-7. Available from: http://www.jclpca.org/text.asp?2018/5/1/20/224900
| Introduction|| |
Orofacial clefts are common birth defects or congenital malformations of the craniofacial region. They may be divided into clefts affecting the lip and palate and clefts affecting the face. Their etiology is complex and they occur between the 4th and 7th weeks of embryogenesis. Clefts affecting the lip and palate may be due to failure of fusion of the maxillary process with the medial nasal bulge of the frontal process or of both palatal shelves, while facial clefts may be due to either a failure of fusion or a disorder in the migration of neural crest cells. According to Gorlin et al., cleft lip and palate make up approximately 65% of all anomalies presenting in the head and neck region. The worldwide prevalence has been cited as 1:700 live births. Research by Tolarová and Cevenka, found that a baby is born with a cleft every 2 min, which means that 700 are born per day or 240,000/year.
Many genetic and environmental factors have been cited as responsible for their etiology and pathogenesis, either individually or through the interaction of complex biological pathways. Current evidence has shown that the incidence of clefts varies according to ethnicity, socioeconomic status, and geographic region. This all serves to have an adverse effect on speech, hearing, appearance, and long-term psychological state.,
The prevalence of orofacial clefts shows considerable international variation. African studies show a low prevalence of these congenital malformations and this could be due to poor record keeping and a lack of data capturing. The management of these malformations is complex and requires a multidisciplinary approach involving a team of specialists. Epidemiologic studies help with the planning of resources for better management of this problem. The aim of this study was to create an electronic database and to perform an epidemiological survey of all orofacial clefts seen at the MOHC, Cleft Clinic in South Africa from its inception in 2003 to December 2014.
| Materials and Methods|| |
The records of 383 patients affected with a cleft lip and/or palate were obtained from the Sefako Makgatho Health Sciences University, Medunsa Oral Health Center Department of Orthodontics. All of these patients presented to the Medunsa Oral Health Center between 2003 and December 2014 and all patients were included in the study. Ethical approval to conduct the study was obtained from the Medunsa Research and Ethics Committee (MREC) as verified by protocol number: MREC/D/319/204 and informed consent was obtained. The sample consisted of 218 males and 165 females, whose ages ranged from 1 week to 19 years. The patients were of varied ethnicity and both syndromic and nonsyndromic clefts were included in the study.
A data base was created, using Microsoft Access 2010. All data was then transferred from the patients file records to the database. Gender, ethnicity, site of cleft lip, and palate, as well as any family history of a cleft lip and palate were recorded. Patients were then classified according to Kernahan's Y classification of cleft lip and palate while facial clefts were classified according to Tessier's classification. The “Y” classification system describes the cleft region, site of the cleft, degree of the cleft, rare and asymmetrical clefts, and is computer database friendly. Any files in which the site and degree of the cleft were not documented or there were inconsistencies present, was recorded as cleft unknown to prevent corruption of the data. As a result 57 patients were not classified according to Kernahan's Y classification, 35 of whom were female and 22 male. Therefore, when calculating the distribution of clefts these 57 patients were excluded from the study, but since their demographic data and familiar histories were all clearly indicated they were included when looking at our other objectives. Once data capturing was completed, it was thereafter verified. Records of 10% of the patients were reassessed and reentered at a later stage for reliability testing.
Once the data capturing was complete, it was then printed in the form of Excel spread sheets. The data analysis was primarily of a descriptive nature. Categorical data was summarized by frequency counts and percentage calculations. Continuous data was summarized by sample size, mean, standard deviation, median, interquartile range, minimum and maximum values. All statistical procedures were performed on SAS Release 9.2 running under Microsoft Windows 2010. Results from any inferential statistical tests was then interpreted as descriptive for the sample and P ≤ 0.05 was considered as statistically significant.
| Results|| |
Clefts affecting the lip and palate
A total of 383 patients were recorded, of this 57 patients were found with incomplete records where demographic data was present; however, the site and or the extent of the cleft was not classified, due to poor record keeping or an inability to correctly classify and identify the cleft. Hence, these patients, 35 of whom were female and 22 male, were excluded when calculating the frequency of cleft distribution.
It was found that unilateral clefts accounted for 47%, while bilateral clefts, accounted for 23% and clefts of the palate accounted for 30% of the total sample size [Figure 1]. Overall clefts on the left side accounted for 88 (56.4%) and clefts on the right side accounted for 68 (43.58%), of the total number of unilateral clefts, thus making clefts on the left side more common that clefts on the right side. It was further found that 45.8% of the patients presented with a cleft which affected the lip and palate, 24.2% were found with a cleft affecting just the lip and in 30% only the palate was affected [Figure 2].
|Figure 1: Classification distribution according to unilateral, bilateral and clefts affecting the palate|
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|Figure 2: Classification distribution according to clefts affecting the lip, the palate and a combination of the lip and palate|
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The most common cleft to present to our cleft clinic is a bilateral complete cleft. It was found to be present in 52 patients or 15.95% of the total sample size. It was also the most common cleft found in both females and males, occurring in 15.3% of females and 16.78% of males. The next most common clefts were the clefts of the soft palate and uvula, as well as a unilateral complete cleft occurring on the left side. They were found to occur in 40 patients each or 12.2% of the total sample size. Cleft of the soft palate and uvula was found in 13.1% of females and 11.1% of males, while the unilateral complete cleft on the left was found in 10.9% of females and 13.9% of males.
The occurrence of a unilateral complete cleft on the right side was also high, with it being found in 37 (11.3%) of the patients, of which 18 (8.2%) were in females and 19 (13.2%) were in males. Despite this a unilateral complete cleft on the left side was still more common. Another common cleft found was a cleft of the posterior hard palate and soft palate. It occurred in 33 (10.12%) of the patients, 18 (9.83%) of whom were female and 15 (10.4%) of whom were male. A unilateral cleft lip and alveolus on the left side was also seen in 33 (10.12%) patients, 18 (9.83%) of whom were female and 15 (10.4%) of whom were male.
The following less common clefts were each found occurring in only one patient and were as follows: (1) Cleft soft palate, (2) Unilateral cleft lip, alveolus, hard, and soft palate on the left side, (3) Cleft of the anterior and posterior hard palate, (4) Bilateral cleft of the alveolus, hard palate, soft palate, and uvula, and (5) Cleft of the anterior and posterior hard palate, soft palate, and uvula.
Facial clefts were not found to be very common in our clinic with only eight patients or 2.4% being affected. Files of 3 (0.92%) of the patients attested that they did present with a facial cleft; however, the nature of the facial cleft was not specified. The most common facial cleft found was that of cleft number seven, which occurred in two (0.6%) of the patients, while facial clefts 0, 1, and 5 were each seen occurring in only one patient each.
Records showed that none of the cleft patients had a maternal or paternal family history. In the 198 patients who acknowledged having a sibling from the same parents, four (1.04%) were found to have either a brother or sister who was also affected by this condition. Two sets of twins were also found to be affected and in 13 (3.4%) cases there was a cousin who also presented with the condition [Figure 3]. Hence, it can be said that 21 patients or 5.48% represented with a positive family history and cousins were more affected than any other relative.
Out of the 383 patients at the clinic, 362 were Black, 13 were Caucasian, two were Chinese and one was Indian [Figure 4].
A total of 218 (56.92%) out of 383 patients were female, while 165 (43.08%) were male [Figure 5]. In both groups, the most commonly identified cleft was a bilateral complete cleft. The second most common cleft in females was a cleft of the soft palate and uvula; however, in males it was a unilateral complete cleft on the left side.
There were no reports of the following clefts occurring in females: (1) Midline anterior and posterior hard palate, soft palate, and uvula; (2) Bilateral cleft of the lip, alveolus, anterior, and posterior hard palate; and (3) Bilateral cleft lip, alveolus, and anterior hard palate. Although they were reported in males, the frequency was low with not more than two cases being reported in each category.
Males presented without any reported cases of the following variations: (1) Unilateral cleft lip, alveolus, hard, and soft palate on the left side; (2) Midline cleft of anterior and posterior hard palate; (3) Bilateral cleft of the alveolus, hard palate soft palate, and uvula; (4) Unilateral cleft lip, alveolus, and anterior, and posterior hard palate on the right side; (5) Bilateral cleft of the alveolus and anterior hard palate; and (6) Cleft soft palate. Although these clefts were found to occur in females, the frequency was very low, with no more than two cases being reported in variation.
Overall it was noted that females presented with a greater variation of the different types of clefts but this could also be attributed to the fact that there were more females that presented to the clinic than males.
| Discussion|| |
In South Africa, private and public health-care systems exist in parallel to try and serve its population of approximately 55.91 million, with a birth rate of 20.5/1000. However, gross disparities in this equilibrium as a result of our previous apartheid regime, as well as lack of education and job opportunities have culminated in the public system serving about 80% or the vast majority of the population, while the wealthier remaining population use the private system. Chronic underfunding and understaffing in the government-based public sector have further resulted in over 70% of our doctors leaving to see to the needs of the minority that can afford private healthcare, while the remaining 30% struggle to provide quality of service under sometimes trying situations. It is these current problems that the government hopes to address in its future plans to unite both sectors with the implementation of a national health insurance.
There are currently four multidisciplinary cleft clinics in South Africa, which are attached to a government hospital, as well as an academic institution. Three of which are based and serve the 12, 27 million population of Gauteng, with our institution making up one of the three. We are located in one of the largest public referral hospitals in the country, with approximately 1400 new patients reporting to our clinic on a monthly basis. To date cleft reporting out of Africa has been very poor; hence, the worldwide belief that it has a low prevalence among Black people. Ideally a national database is needed to correctly report on its prevalence in our country as a whole in both public and the private sectors.
Our study just serves as a pilot study looking at the cleft distribution at our centre. It is a study, we hope to grow by promoting better digital record keeping among the other institutions as well as greater awareness among doctors, due to the fact that many minor clefts may be undiagnosed or neglected in an already burdened health-care system. We also need to promote a greater patient awareness of this relatively common and nonlife-threatening condition which in African culture may be attached with a stigma which prevents the patient or parent from seeking help themselves. In some cases, these patients may even present to an African witch doctor or Sangoma, as opposed to seeking professional medical help. It is in these cases that information and education plays a key role.
Clefts affecting the lip and palate
In this study, the most common cleft was a bilateral complete cleft, which was found in 13.5% of patients. It was also the most common cleft in both males (14.54%) and females (12.8%). Unilateral clefts accounted for 47.85% of the total number of clefts seen, while bilateral clefts accounted for 23% and clefts of the palate accounted for 29.1%. This study is in agreement with the study conducted by Shapira et al., who found a higher prevalence of unilateral clefts, followed by bilateral clefts and lastly clefts of the palate. In their study, they found that 68.5% of patients presented with a unilateral cleft, while 21% had a bilateral cleft of the lip and palate and 11% were found to have an isolated cleft of the palate. In summary, they had a higher percentage of patients presenting with unilateral clefts, a slightly lower percentage of bilateral clefts and a much lower percentage of clefts of the palate. The number of patients presenting with clefts of the palate in our study was in fact more than twice, that of Shapira et al.
Our study is also in accordance with the study conducted in France by Doray et al., who also found that unilateral clefts were the most common clefts seen  although the frequency in their study (70%) is much higher than that in our study (47.85%). They also found that 55% of these clefts occurred on the left side; hence, clefts on the left side were more common than those on the right side. In our study, we found that 56.4% of patients presented with a cleft on the left side while only 43.58% presented on the right side; hence, we are in agreement with the Doray et al. study. An investigation into four cleft palate centers in New York, which was conducted by Shapira et al., found that unilateral clefts were six times more common than bilateral clefts and there is a definite predominance toward the left side. A study by Manyama et al., conducted in Tanzania, also found that unilateral clefts were the most common clefts seen and there was a greater predominance toward the left side. They found that 43.7% of clefts were found on the left side, 28.8% on the right side, and 18.3% were bilateral.
In most studies across the world, clefts of the lip and palate have a higher incidence than isolated cleft lip.,,, Jagomagi et al., showed that clefts of the lip and palate account for 50% of all clefts. A study by Ademiluyi et al., found that 19% of their patients presented with a cleft lip, 35% with a cleft lip and palate and 28% with an isolate cleft palate. In Uganda, a study by Dreise et al., found that 63.2% of their patients presented with a cleft lip and palate, 31.2% had an isolated cleft lip and 5.3% had an isolated cleft palate. In accordance with the majority of the studies conducted worldwide, we also found that clefts of the lip and palate had a higher incidence than isolated cleft lip. In our study, 45.8% of the patients presented with a cleft lip and palate whilst 30.06% had a cleft of the palate and 24.2% had a cleft affecting the lip. Although most patients in our study were affected with a cleft of the lip and palate, our study is still in agreement with that of Ademiluyi et al., who found that clefts of the palate are more common than clefts of the lip. This is contrary to the findings of Dreise et al., who found that clefts of the lip were more common than clefts affecting the palate.
A previous South African study conducted by van Wyk et al., found similar results to our study [Table 1]. They found that 50.4% of patients presented with a cleft lip and palate, 26.9% presented with a cleft palate and 22.7% had a cleft lip. Hence, we can say that in both studies the order of frequency is the same, with a cleft of the palate occurring more frequently than a cleft of the lip.
Facial clefts are generally very rare. Various studies from around the world have placed the incidence of facial clefts in the range of 0.3%–1.1%., In South Africa, Bütow and Botha, conducted an analysis of their data base and found the prevalence to be 0.69%. In our study, however, we found that 2.4% of the patients presented with a facial cleft. While this is still low, it is still higher than statistics which is reported worldwide.
A positive family history of clefts has been reported in several studies with varying incidences. Rajab and Thomas reported a frequency of 23%; Kumar et al. found a frequency of 26.8%; Aljohar et al. reported finding 28%; while Aqrabawi found a 0% frequency. The frequency also varied according to the different countries in which the studies were conducted, a study in Czechoslovakia reported the frequency at 18%, while a study in Brazil placed the frequency at 35%. Goto et al., also found that a positive family history might be associated with a two-fold higher risk of cleft presentation.
In our study, we found that 21 (5.48%) of the patients presented with a positive family history of clefts. A study conducted in Yemen by Ali Esmail et al.; found that of 1110 patients who presented with a cleft, 18% had a positive family history. According to them, this is somewhat lower than in other studies where the prevalence of clefts in family members ranged from 20% to 42%. Hence, since we found that only 5.48% of our patients presented with a positive family history, it can be said that this value is also lower than that found in other parts of the world. However, a study by Gordon et al. in Cape Town; South Africa, found that 40% of the patients that presented with a cleft lip and palate had a positive history of clefts in the family. This difference could be due to variety of factors such as genetic and racial diversity due to geographic location or a lack of stability, in the family network where a parent is absent and their family medical history is unknown.
In our study no patient acknowledged to having either a mother or father affected by the condition. However in 4 (1.04%) cases a sibling was affected, in two cases a set of identical twins were affected and in 13 (3.4%) patients a cousin was affected. Therefore the most commonly affected relative was a cousin. This is in accordance with Martelli et al. who also found that cousins were the most frequently affected relative type, while Goto et al. found that parents and siblings were more frequently affected. A Danish study conducted by Christensen and Fogh-Andersen, found that in the case where twins were affected, 60% of monozygotic twins were both affected but only 10% of dizygotic twins presented where both twins were affected. The two cases that presented in our clinic were the cases of monozygotic twins and both twins were affected.
The vast array of studies conducted showed a marked variability based on ethnic and racial distributions. In 1972, Ross and Johnston found that African Americans had the lowest incidence of clefts. A study by Dreise et al., in Uganda, found that the incidence is higher for native Africans, but is still lower than the incidences for other races. In our study, we found that most of the patients that presented to the cleft clinic were Black, with a frequency of 362 (94.52%).
Previously in South Africa, van Wyk et al., reported incidence rates of 1.38/1000 and 0.42 per 1000 for Caucasian and Black, respectively. According to this the incidence is higher in Caucasian patients than in Black patients. In our study, the frequency in Caucasians was low at 13 (3.39%). A study by Cooper et al. and Altunhan et al. noted that the Asian populations had the highest reported incidence of clefts,, while Allam et al. noted a high incidence in Native Americans. According to Ali Esmail et al., the prevalence of clefts in the middle-east is unknown.
These marked variations in the literature can be attributed to geographic location of these race based studies. Our study was carried out in Africa and in an area where the majority of the population in the immediate and surrounding areas are Black. Hence, our study shows a high frequency in the Black population. Likewise, Morrison et al., conducted a study in the Western Cape. Using hospital data they found that between 1983 and 1984; 52 children were born with a cleft, of these 3 were Black, 43 Coloreds and 6 were Caucasians. They hence reported a high incidence in Coloreds, but this again could be related to the geographic area where the research was carried out.
The distribution around the world may also vary tremendously due to differences in birth prevalence, as well as deficiencies in recording of births and birth defect surveillance systems, particularly in many parts of the developing world.
In this study, we found that females were more affected than males, with a frequency of 218 (56.92%) in females and 165 (43.08%) in males. This is in contrary to a study conducted by Oka, which showed that boys were more often affected than girls with a ratio of M:F (2:1). They also found that boys presented with more severe clefts than girls and that girls were shown to be more affected by isolated cleft palates than boys.
In our study, the highest occurring cleft in both males and females, is a bilateral complete cleft. Since this is a severe cleft, this study is contradictory to that by Oka, which found that boys presented with more severe clefts than girls. In our study, there was only 1 incidence of an isolated cleft palate and it occurred in a female, with no occurrence reported in males. This is in agreement with the studies by Shapira et al., who found that isolated cleft palate occurred most often in females.
Contrary to our study, other studies conducted worldwide reported higher incidences in males as opposed to females.,,,,, However, a survey conducted in Japan by Natsume et al., found that there is a higher incidence in females than males. In their survey of all the maternity institutions in Japan between 1994 and 1995, 437 patients were reported as having a cleft. Of this 218 were male, while 219 were female. However, even though more females than males were affected, the difference was only one patient hence we can say that it was equally high in both groups.
In South Africa, a study conducted in the Transvaal by van Wyk et al., found that cleft palates were more common in females. In our study if we look at clefts affecting the soft palate and hard palate, for example: (1) Cleft soft palate and uvula, (2) Cleft soft palate, (3) Cleft of the posterior hard palate, soft palate and uvula, (4) Cleft posterior hard palate and soft palate, (5) Cleft posterior hard palate; and if we look at the frequencies of these combined, we also found that clefts of the palate are more common in females than males with a frequency of 79 (20.6%) in females and 45 (11.7%) in males.
| Conclusion|| |
From this study we can make the following conclusions regarding the distribution of cleft patients at the MOHC:
- The distribution of the classification of clefts varies greatly depending upon geographic location, ethnicity and methods of reporting. We have found that our study is in agreement with certain studies while being contra-indicatory to others. Overall unilateral clefts are more common than bilateral clefts; the left side is more often affected than the right side; most patients presented with a cleft affecting the lip and palate, followed by a cleft of the palate and finally a cleft of the lip and the most common cleft to present to our clinic with a high prevalence in both males and females is a bilateral complete cleft. Facial clefts are not a common occurrence in our clinic however its prevalence in our clinic is higher than that reported in other parts of the world
- When considering the familial distribution, we found that only 5.48% of our patients had a positive history of cleft occurrence in the family and cousins were more likely to be affected than any other relative
- The distribution according to race shows that in our community more Black patients were affected than in other geographic locations. However this could be due to the fact that in our feeder area more Black patients are referred
- Our finding that more females are affected as opposed to males, is in agreement with certain international studies. However there is more worldwide evidence that shows that males are more likely to be affected than females ,,,,,
- South Africa is a country with a diverse spectrum of racial and ethnic groups hence regional findings may vary based on the surrounding population. Ideally a National data base is needed, which will reflect the true distribution seen in this country.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]