Cleft lip and palate in general dental practice: filling in the gaps

Epidemiology

CLP is reported to occur in 1 in 600–700 live births in the UK,¹ with cleft lip (CL) comprising 23.5%, cleft palate (CP) 44.9% and CLP 31.6% of these live births.⁴ However, the incidence of CP has significant geographical variation, between 1.3 and 25.3 per 10,000 live births worldwide,⁵ with the highest rates in British Columbia and the lowest in Nigeria. Incidence of CLP also varies by ethnicity as shown in Table 1.⁶

The majority of clefts are isolated (76.8%), and approximately 7.3% are associated with recognized syndromes while 15.9% occur with malformations in other systems, most commonly with congenital heart defects, deformations, hydrocephaly, urinary tract defects and polydactyly. Isolated CP is more frequent in females, with a female to male ratio of 2:1, but CLP is more frequent in males than in females, at the same ratio.⁵

Aetiology

CLP has a multifactorial aetiology with interplay of genetic and environmental risk factors.⁶ While some syndromic clefts often have a clear inheritance pattern, non-syndromic clefts show a complex heterogeneous aetiology. Orofacial clefting occurs as a result of atypical embryonic development between the fourth and tenth week in utero. Any disruption to these processes may result in CLP.

Classification

The complexity and variation in CLP presentations has made universal acceptance of a single classification system difficult. The first attempt to develop a classification for clefts was by Davies and Ritchie in 1922.⁸ Subsequently, many other different classifications of CLP have been proposed and used historically, based on embryological principles, morphological features, or a combination of both.

In the UK, the LAHSAL descriptive system of CLP classification is currently the most widely used, primarily for its simplicity and transferability to the International Statistical Classification of Diseases and Related Health Problems 10th Revision (ICD 10)⁹ and the Craniofacial Anomalies Register. LAHSAL has been shown to have a high degree of inter- and intra-observer reliability.¹⁰ The system was modified by the Royal College of Surgeons from Kriens' original ‘LAHSHAL’¹¹ by omitting one ‘H’ from the acronym to give ‘LAHSAL’. The classification is divided into six parts:

In addition, an asterisk (*) is used to represent a microform lip, submucous cleft palate or a Simonart's band.

A capital letter in the LAHSAL classification indicates a complete cleft, whereas a small letter indicates an incomplete cleft. Any anatomical area that does not have a cleft is indicated with a full stop or a dash, for example: incomplete hard palate, complete soft palate defect and right incomplete cleft lip would be classified thus: ‘l . hS ..’ Figure 1 shows a diagrammatic representation of this classification.

Structure of the CLP team

The Clinical Standards Advisory Group (CSAG) report on cleft lip and palate, published in 1998, audited outcomes of non-syndromic unilateral cleft lip and palate (UCLP) patients aged 5 and 12 years old over a 15-month period. Of children aged 5 and 12 years old, 40% and 20%, respectively, had active caries requiring dental treatment, while 42% of 12-year-olds had seriously deficient or failed bone grafts. Dental arch relationships were ‘poor’ or ‘very poor’ in 37% of 5-year-olds and 39% of 12-year-olds and were likely to require further surgery to correct the skeletal discrepancy. A series of recommendations was made (Table 4).¹² In 1992, prior to CSAG, a six-centre international study of treatment outcomes for UCLP patients concluded that key indicators for good patient outcomes involved standardization, centralization and high volume operators.¹³

Following these recommendations, moves were made to centralize CLP care, which now has 11 managed clinical networks comprising 16 surgical sites that follow a multidisciplinary approach (Table 5). The investigations performed by the CSAG were repeated some 15 years later in a study known as Cleft Care UK. Reassuringly, it was found that there were marked improvements in some outcomes, such as dento-alveolar relationships and speech. However, and of great concern, was the finding that the percentage of children with caries experience (dmft > zero) had only reduced to 52% from 55%,¹⁴ highlighting an area in which the role of the primary care service holds significant importance.

Dental reviews and interventions that involve the dentition are centred around orthodontics and paediatric dentistry in the CLP hub team; however, a significant component of care is delivered in primary care (Table 6). This highlights the need for shared care and the importance of clear communication between the various healthcare providers. Considering that the two main dental issues (dental caries and periodontal diseases) are wholly preventable, this should be a cause for a concerted and targeted effort to create and deliver interventions for this priority group.

Role of the GDP

The journey of a child born with a cleft is long and complex,¹⁵ yet the role of the GDP is critical because these patients have a higher risk of caries, periodontal disease and an increased incidence of dental anomalies. Children born with a cleft have a higher susceptibility to caries in both their deciduous and permanent dentition, so early detection and treatment is required.¹⁶ In the UK, advice from Public Health England and the British Society of Paediatric Dentistry's ‘Dental Check by One’ campaign is for all children to be seen by a dentist by 1 year of age, and ideally as soon as primary teeth erupt. Good communication and joint care between the GDP and CLP team gives the GDP the ability to more confidently deal with the complexities of care.

All CLP patients are encouraged to register with a GDP as soon as possible to start shared care early in the child's journey and to acclimatize the child to the dental setting. This, and preventive interventions, are key to dental care for those children born with a cleft. The majority of complex dental care is usually carried out by the CLP team; however, there may be a number of years in between dental assessments at the centre, and GDPs, along with orthodontic colleagues and MDT co-ordinators, are instrumental in maintaining the oral health of the child with CLP.

Challenges of CLP management

High caries risk

There is good evidence that children born with clefting have a higher risk of caries.^17,18 Some work suggests that the oral microbial profile of those born with a cleft may have an impact between the ages of 0 and 3 years;¹⁸ however, this may not be a factor in older children.^19,20 The impact of high caries risk could increase the chances of these children requiring a general anaesthetic.²¹ Their dental treatment plans are often complicated by orthodontic needs along with further surgical treatments around the cleft site, such as alveolar bone grafting (Figure 2). This high caries risk is also more likely to be associated with a lower health-related quality of life (Figure 3).²²

Advice for GDPs:

Management of all children born with clefts as higher caries risk;¹⁶

Check ups every 3–4 months with topical fluoride varnish (2.2% NaF);

Ensuring to follow radiography guidelines, all children with CLP should have radiographs as part of the cleft audit at the ages of 18 months, 5 years, 15 years and 20 years.

Periodontal diseases

Children born with a cleft often have poor oral hygiene¹⁹ and a corresponding high risk of gingivitis.¹⁷ The severity of periodontal disease may relate to the extent of the cleft and the involvement of the lip, alveolus and palate.²³ It is important to note that periodontal diseases can also be localized, or more severe in teeth adjacent to the cleft area (Figure 4).¹⁹ Individualized oral hygiene instruction and equipment can be central to improving oral hygiene in CLP patients.²⁴

Advice for GDPs:

Oral hygiene instruction around CLP site;

Modified BPE scoring;

Ensuring reinforcement of oral hygiene during orthodontic treatment.

Malocclusion and dental anomalies

Many studies show that there is a high prevalence of dental anomalies, mostly surrounding the cleft site, affecting approximately 20–80% of those with CLP^25,26,27 and there are significant differences from those in the non-cleft population.²⁷ The most common dental anomalies seen in both syndromic and non-syndromic clefting include:

Tooth agenesis (Figure 5);

Fused and geminated teeth (Figure 6);

Supernumeraries (Figure 7);

Microdontia;

Macrodontia;

Ectopic eruption (Figure 7);

Transposition;

Dens in dente (Figure 8);

Natal teeth (Figure 9).

Due to these dental anomalies, close involvement with orthodontic and paediatric dentists is often essential in the care pathway.

Advice for GDPs:

Good medical history;

Consult with paediatric dentist or paediatrician if any specific concerns;

Closely monitor eruption of the developing dentition, and if concerned, discuss with paediatric dentist;

Be aware of any correspondence regarding the GDP's role in monitoring and managing conditions;

Encourage children born with a cleft to prioritize oral health and appreciate its benefits.

Conclusion

Children born with a cleft require multidisciplinary care from a multidisciplinary team, within which the GDP plays an important role. Considering the significant number of people affected by orofacial clefting, it is useful to understand the wide range of severities that may present, and the syndromes and other features that may be associated.

The GDP should be comfortable communicating with the centralized CLP team ‘hub’ to optimally co-ordinate the patient's care. While the specialized hubs perform complex treatments and surgical procedures to manage the clefting and its sequelae in the hospital setting, GDPs are pivotal in reviewing these patients regularly, and maintaining their oral health. As patients with clefts are at an increased risk of caries and periodontal pathology, especially around the cleft site, they require enhanced prevention and 3-monthly recalls. They may also present with challenging behaviour resulting from the psychosocial impact of CLP, which should be managed considerately.