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 Table of Contents  
Year : 2022  |  Volume : 9  |  Issue : 2  |  Page : 139-144

Profile of cleft lip and palate patients at a dental hospital in Johannesburg, South Africa

1 Department of Orthodontics, The University of the Witwatersrand, Faculty of Health Sciences, School of Oral Health Sciences, Johannesburg, South Africa
2 Department of Orthodontics, University of Pretoria, Faculty of Health Sciences, School of Dentistry, South Africa

Date of Submission06-Dec-2021
Date of Acceptance03-Mar-2022
Date of Web Publication23-Aug-2022

Correspondence Address:
Dr. Fatima Carrim
Department of Orthodontics, The University of the Witwatersrand, Faculty of Health Sciences, School of Oral Health Sciences, Johannesburg
South Africa
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/jclpca.jclpca_43_21

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Objectives: This study aimed to determine the clinical profile of patients with orofacial clefts (OFC) who presented at a dental hospital in Johannesburg, South Africa, from January 1, 2013, to December 31, 2019. The aim of the study is to use the data collected to conduct an epidemiological survey and create an electronic database of all patients with OFC who presented to the hospital. Materials and Methods: A cross-sectional, retrospective record review of all cases of OFC treated at Johannesburg Cleft clinic from January 1, 2013, to December 31, 2019, was conducted. A structured, pretested record review form was used to obtain demographic and clinical information of patients with OFC. STATA version 15 was used to analyze the data and statistical tests were conducted at a 5% significance level. Results: One hundred and thirty-three records were analyzed. The majority were males (n = 68, 51.13%), while 48.87% (n = 65) were females. Most patients were South Africans 91.73% (n = 122,), and the majority were African blacks (67.67%). A statistically significant difference (P < 0.05) was found in gender and racial distribution of OFC. Majority of the sample presented with clefts of the lip and palate 55.64% (n = 74,), followed by isolated CP 24.81% (n = 33), CL 17.29% (n = 23), and 2.26% (n = 3) presented with a facial cleft. Majority of the clefts were described as unilateral (n = 50, 37.59%) and 30.83% (n = 41) of the clefts were described as bilateral. Isolated cleft of the palate accounted for 24.81% (n = 33), while 4.51% (n = 6) were midline clefts. Facial clefts accounted for 2.26% (n = 3). Of all unilateral clefts (n = 50), those who presented on the left side account for 68% (n = 34), while those who presented on the right side accounted for 32% (n = 16). Conclusions: The dental hospital is providing services to a large number of patients with OFC. The study findings should assist in planning services for these patients.

Keywords: Cleft lip and palate, epidemiology, orofacial clefts, South Africa

How to cite this article:
Carrim F, Hlongwa P. Profile of cleft lip and palate patients at a dental hospital in Johannesburg, South Africa. J Cleft Lip Palate Craniofac Anomal 2022;9:139-44

How to cite this URL:
Carrim F, Hlongwa P. Profile of cleft lip and palate patients at a dental hospital in Johannesburg, South Africa. J Cleft Lip Palate Craniofac Anomal [serial online] 2022 [cited 2023 Feb 5];9:139-44. Available from: https://www.jclpca.org/text.asp?2022/9/2/139/354295

  Introduction Top

Congenital malformations are defined as nonprogressive, morphologic anomalies of a single organ or body part due to an alteration or interruption of the primary developmental program.[1] Orofacial clefts (OFCs) are the most common congenital craniofacial malformations with a global prevalence of 1 in 700 live births.[2] Panamonta and Pradubwong conducted a global systematic review in 2015 and reported that Asia had the highest number of reported OFC, while Africa had the lowest number reported, ranging from 0.3 to 1.65 per 1000 live births.[3]

Clefts have a complex etiology resulting from the disruption of the migration and fusion of the various facial processes by environmental, genetic, or combined factors.[4] Genetics has been reported to play a major role in the etiology of OFC. Environmental risk factors that are linked to cleft formation include maternal age, smoking, alcohol, folic acid deficiency, corticosteroid use, diet, and other influences.[4]

OFC can present clinically as typical clefts; which are clefts of the lip (CL), CL and alveolus (CLA), clefts of the palate (CP), and CL and palate (CLP). OFC can occur unilaterally on either the right side or the left side of the face, or bilaterally. Atypical clefts are rare craniofacial clefts with severe deformities of the face and head affecting both hard and soft tissues. These clefts can extend through the center of the face, or laterally, affecting the eyes, nose, and mouth. [Figure 1] shows the clinical appearance of OFC. Typical and atypical clefts can arise as a single, isolated, nonsyndromic anomaly, or as a result of a sequence of a primary defect, or as a multiple congenital anomaly which can be syndromic, chromosomal, or can be idiopathic.[5]
Figure 1: Clinical Appearance of OFC. (a) Bilateral CLP; (b) unilateral CLP occurring on the right side of the face; (c) CP; (d) CL and Alveolus occurring on the left side of the face; (e) Partially repaired atypical facial cleft occurring on the right side of the face, resulting in right anophthalmia. (Pictures reproduced through courtesy of Professor P Hlongwa, Department of Orthodontics, School of Oral Health Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa)

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WHO has stressed the need for countries to address the burden of OFC as well as the importance of research to determine the extent of the crisis, to identify needs that are not met, and to contribute to developing appropriate health policies.[6]

The results of this study will assist to develop an electronic database of patients with OFC who have presented at the cleft clinic. Furthermore, the findings will assist in better understanding of the profile of these patients to plan for services. The aim of this study was to determine the profile of patients and patterns of OFC presenting at the Cleft Clinic.

  Materials and Methods Top

This study was a record review, cross-sectional, retrospective study of patients with OFC who presented from January 1, 2013, to December 31, 2019, irrespective of their treatment stage. Individuals with OFC make numerous visits to the center over a prolonged period. Care was taken to record each individual only once, to avoid duplications. The study setting was at a Dental Hospital in Johannesburg, South Africa. The Dental Hospital, Johannesburg Cleft Clinic, is among a few cleft centers in South Africa, receiving many referrals from surrounding provinces as well as neighboring countries. OFC has been treated in this clinic for over many decades and this study would be the first to describe the profile of OFC at this dental hospital. Ethical approval was obtained from the Human Research Ethics Committee (M1911172).

A data collection form was used to obtain demographic and clinical information on each individual with OFC. The chronological age of patients at their first consultation was documented. Ethnicity of individuals with clefts was recorded from a list of categories: African, colored, Indian or Asian, white, and other. Our study did not intend to perpetuate the apartheid roots of these ethnicity classifications, which are still used in South Africa.[7] It is unfortunate that legislated racism still continues to shape socioeconomic circumstances and access to care in South Africa.[8] Gender, nationality, and patients' hospital classification for patient tariffs was also recorded. The clinical information of the clefts was recorded in four categories: (1) type of cleft, (2) description of cleft, (3) laterality of cleft, and (4) position of cleft in relation to the face and palate.

The information from the record review form was captured in Excel. The data were then cleaned – all samples with incomplete information were removed. The data were stored on a secure computer which was password protected and only the researcher had access to this password. The data were imported into STATA version 15 (StataCorp, College Station, Texas, USA) for descriptive and inferential statistical analyses. Data were summarized by means of frequency counts and percentage calculations. Chi-square test was used to compare significant differences between the following proportions: (1) cleft description and gender and (2) cleft description and race. All statistical tests were conducted at a 5% significance level. The Cronbach's alpha was used to assess the reliability test. The overall test scale alpha value was 0.6468 which indicates an acceptable level of reliability.

  Results Top

The total sample size was 230 patients' records. Of the 230, 97 patients (51 males and 46 females) with incomplete records were excluded from the analysis of the data set. The remaining sample size with complete records comprised 133 patients.

Gender distribution showed that most of the study sample were males (n = 68, 51.13%), while 48.87% (n = 65) were females. Nationality distribution revealed that the majority of the participants were from South Africa, 91.73% (n = 122), while 8.23% (n = 11) were non-South Africans who had not specified their nationality. The racial distribution of this study was as follows: African, 67.67% (n = 90), Asian, 14.29% (n = 19), white, 9.77% (n = 13), and colored, 8.27% (n = 11) [Table 1].
Table 1: Descriptive characteristics of the sample

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[Table 1] also shows the patient tariffs of the sample based on the hospital classification. The most predominant group was HO/HG at 54.89% (n = 73) who do not pay for services. Those with H1 were 26.32% (n = 35) of the sample and pay R75 for every hospital visit. The H2 classification was 7.52% (n = 10) and PH was 6.77% (n = 9). Hospital classification PF and H3 had the least numbers with 3.00% (n = 4) and 1.50% (n = 2), respectively.

Majority of the sample presented with CLP, 55.64% (n = 74,), followed by CP, 24.81% (n = 33), CL, 17.29% (n = 23), and 2.26% (n = 3) presented with a facial cleft [Figure 2].
Figure 2: Distribution of cleft types

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CL included the CL only and/or the cleft of the lip and alveolus, where the palate was not involved. Of the 23, CL that were documented, 7 (30.43%) were cleft lip, and 16 (69.57%) were cleft of the lip and alveolus.

Majority of the clefts were described as unilateral (n = 50, 37.59%) and 30.83% (n = 41) of the clefts were described as bilateral. Cleft of the palate accounted for 24.81% (n = 33), while 4.51% (n = 6) were midline clefts. Facial clefts accounted for 2.26% (n = 3) [Figure 3]. Of all unilateral clefts (n = 50), those who presented on the left side accounted for 68% (n = 34) while those who presented on the right side accounted for 32% (n = 16).
Figure 3: Cleft Laterality

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Gender differences in cleft description

Unilateral clefts presented in 35.29% of males (n = 24) compared to 40% (n = 26) in females. Bilateral clefts were predominant in males at 33.82% (n = 23) compared to females who presented with 27.69% (n = 18). All midline clefts presented in males at 8.82% (n = 6) of the sample. There was a statistical significance in gender distribution of cleft description with P < 0.042.

Racial differences in cleft description

The Asians had the highest frequency of unilateral clefts followed by the Africans. Bilateral clefts were found predominantly in the Africans. About 83% of midline clefts were noted in the Africans. There was a statistically significant difference regarding racial differences in cleft distribution with P < 0.042.

Facial clefts

Three patients out of 133 patients (2.26%) presented with facial clefts in our study. These results are similar to a study conducted by Moodley et al.in 2018 that reported a facial cleft frequency of 2.4%.[9] In 2010, Bütow and Botha found the frequency of facial clefts to be 0.69%.[10] Worldwide incidence is estimated to be between 1.4 and 4.9 per 100,000 live births.[11] Our study also found that all facial clefts identified were in female patients. In 2017, a study by Kalantar-Hormozi et al. found that out of 80 rare facial clefts, 48.7% were males and 51.3% were females.[11]

  Discussion Top

The comprehensive management of patients with OFC should begin at birth or during early infancy and continue into adulthood. The ages of patients with OFC in our study ranged from 0 to 40 years with 50% of the sample being below 13 years. It is evident that many patients with OFC continue to present to this hospital for continued management even into adulthood.

Most of the patients in this study were below the age of 6 years when they presented for their first assessment at this hospital. This age is old in comparison to other studies where majority of the patients presented before they were one year old.[12],[13] The late first presentation for consultation could be due to late referral of patients from other provinces or relocation from other regions.

The Craniofacial Anomalies Project was undertaken in 2011 by the World Health Organization (WHO) with the aim of collecting data regarding craniofacial anomalies using a standardized protocol from different countries. WHO aimed at documenting international cleft variation and thus improving the current understanding of birth prevalence as well as associated international, geographic, cultural, and ethnic variations.[14] A total of 7704 cleft cases were provided from 30 different countries from the year 2000–2005. Isolated clefts amounted to 76.8% (5918), 15.9% (1224) had malformations in other systems, and 7.3% (562) occurred as part of recognized syndromes. CL alone was found in 3.28 per 10 000 cases and CLP was found in 6.64 per 10 000 cases.[15]

Our study findings showed that more than half of the sample presented with CLP (55.64%). CP presented in 24.81% of the sample and CL in 17.29% of the sample. These results are concurrent with other studies, showing that CLP has a higher prevalence than CL alone.[16] In 2010, Jagomagi et al. published a study wherein of the 583 clefts assessed, 42% had CLP, and 19% had CL.[16]

This study results have found similar order of frequency compared to other studies,[17],[18],[19] with CLP being the most common followed by CP and lastly CL being the least common. A study in Mexico by Gonzales et al. also reported the following frequency: CLP 70%, CP 21%, and CL 8%.[19] A South African study conducted in 1987 also showed a similar pattern; 50.4% with CLP, 26.9% with CP, and 22.7% with CL[17] [Table 2]. Ademiluyi et al. found 35% of their patients with CLP, 28% with CP, and 19% with CL.[18]
Table 2: Comparison of studies done in Africa regarding cleft types

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The findings of this study have shown that the most common cleft was unilateral clefts (37.59%), followed by bilateral clefts (30.83%) and lastly palatal clefts (24.81%) with regard to cleft distribution. Shapira et al., in 1999, reported a similar order of frequency to our study findings.[20] Our results were also similar to a study conducted in Tanzania by Manyama et al., who reported that unilateral clefts were much more common than bilateral clefts.[12] Of the 50 unilateral clefts in our study, 34 (68%) were left-sided clefts and 16 (32%) were right-sided clefts.

Gender distribution

Our study findings showed that of the 133 study sample, the majority were males (51.13%) and 48.87% were females. The gender distribution of our sample is similar to other studies that have shown males are more likely to be born with clefts in general compared to females.[12],[19],[21],[22] Males are also reported to have a more severe form of cleft than females.[21] A 1994 study found that male gender, white ethnicity, and nonmetropolitan background were all higher risk factors for being born with a cleft.[23] Another study reported that males have a 3.5-fold greater chance of being born with a cleft compared to females.[24]

Our study findings indicated the predominance of females with isolated CP (n = 27.69%) compared to males (n = 22%) which has been found in many findings globally. A South African study conducted in Pretoria by van Wyk et al., in 1987, also reported CP being more common in females.[17] Oka, in 1999, reported similar findings of females being commonly affected by isolated CP than males, which is concurrent with the findings of other studies around the world.[20],[21],[22] A Canadian study reported a similar finding; CP was predominantly found in females and CL and CLP were predominantly found in males.[25]

Our study findings showed that CLP was the most common cleft identified among both gender groups, with male predominance. Similar findings were reported in another South African study done in 2018 by Moodley et al.[9] All of the facial clefts in our study were found in females and none in males. However, males presented more with bilateral clefts compared to females. In terms of cleft description, females presented more with unilateral clefts as well as palatal clefts in comparison to males. All of the midline clefts were found in males and none in females. These results were statistically significant (P < 0.05).

Racial distribution

Our study was done in South Africa, where the majority of the population in the immediate as well as the surrounding areas are African; thus, we had a higher portion of Africans compared to other races in our parent sample. Of the sample of 133 patients in our study, the African race had the highest frequency (67.7%), followed by the Asian race (14.3%) then the white race (9.8%), and finally the colored race (8.2%). Cleft distribution among races showed the highest percentages were as follows: unilateral clefts were found in 42.11% of Asians, bilateral clefts were found in 34.4% of Africans, and palatal clefts were found in 46.15% of whites. All of the facial clefts and most of the midline clefts were found in the African race. These results were found to be statistically significant (P < 0.05).

Prevalence studies in South Africa were done during the pre-democratic era and are over 30 years old.[26],[27],[28] A study done in 1987 by van Wyk et al.showed a higher prevalence of clefts in whites compared to African patients, and rates were reported to be 1.38 and 0.42 per 1000 live births, respectively.[17] In 1985, Morrison et al. conducted their research in the Western Cape and reported that 83% of clefts were found in coloreds.[29] A recent study conducted in 2019 by Hlongwa et al.on the epidemiology of OFC in South Africa reported a prevalence rate of 0.3 per 1000 live births.[30] Similarly, in Uganda, Dreise et al. found the highest portion of affected patients to be African.[31] These marked racial differences appear to be regional. The main race that populates the specific geographical location in which the research was done will appear to dominate the cleft frequency counts.

Limitations of the study

Our study sample was based on the hospital records which were not intended for research; therefore, challenges with incomplete records were encountered. The unavailability of clinical records possessed one of many issues to clinicians and more so researchers are faced with this challenge when trying to complete an audit.

A study by Wegner and Rhoda reported the impediments in “archival survey-research in a rural community” in South Africa. They found that the possible issues arising from hospital files were incorrect names, incorrect file numbers, file numbers and names not matching, missing folders, illegible file entries, empty folders, and duplication of files.[32] Therefore, inaccurate records impeded research, thus compromising the service given to the patient and the overall work of the clinician.

  Conclusions Top

  • The Dental Hospitals Cleft Clinic is providing services to a large number of patients with OFC
  • The racial distribution shows that Africans have a higher cleft frequency and this could be due to the location in which the research was conducted as this aspect matches the racial distribution in the city and the country
  • The data collected in this study could be used as a baseline for an electronic cleft database for this cleft clinic. This would aid in the planning and management of the resources that are required for patients with OFC.


  • Further research is recommended to analyze and explore the data regarding patient and parent perceptions of OFC, treatment and surgical waiting times, treatment costs, and outcomes
  • Taking into consideration the increasing world population as well as annual birth rates, OFC places an enormous burden on health-care systems worldwide. It will be beneficial to establish an active birth surveillance system for congenital anomalies in South Africa. This will improve public health service planning, it will contribute to developing appropriate health policies as well as enabling comprehensive management of individuals with OFC.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

  References Top

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Mossey P. Epidemiology underpinning research in the aetiology of orofacial clefts. Orthod Craniofac Res. 2007;10:114-20.  Back to cited text no. 2
Panamonta V, Pradubwong Msn S, Panamonta Md M, Chowchuen B. Global Birth Prevalence of Orofacial Clefts: A Systematic Review. J Med Assoc Thai. 2015;98:S11-21.  Back to cited text no. 3
Wong FK, Hägg U. An update on the aetiology of orofacial clefts. Hong Kong Med J. 2004;10:331-6.  Back to cited text no. 4
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Kalantar-Hormozi A, Abbaszadeh-Kasbi A, Goravanchi F, Davai NR. Prevalence of rare craniofacial clefts. J Craniofac Surg. 2017;28(:e467-e70.  Back to cited text no. 11
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  [Figure 1], [Figure 2], [Figure 3]

  [Table 1], [Table 2]


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