What are the implications of preterm (premature) births on long-term craniofacial growth and tooth formation?

Preterm Birth and Long-Term Craniofacial and Dental Implications

Preterm birth significantly increases the risk of craniofacial abnormalities and dental developmental problems, with very preterm and extremely preterm children (born before 32 weeks gestation) showing the highest prevalence of malocclusions, altered craniofacial morphology, enamel defects, and greater orthodontic treatment needs compared to full-term children.

Craniofacial Growth Alterations

Palatal and Skeletal Changes

• Preterm infants develop positional skull deformities, particularly from supine positioning, which can be cosmetically disturbing to parents 1
• Altered palatal morphology occurs in the short term among premature children, with oral intubation being a significant contributing factor to these alterations 2
• Multiple craniofacial parameters differ significantly between preterm and full-term born children, including altered facial proportions and skeletal relationships 3
• Very preterm and extremely preterm children (born more than 8 weeks before term) demonstrate the most pronounced craniofacial alterations 4

Specific Morphological Findings

• Preterm children show localized enamel hypoplasia, crown dilacerations, and palatal distortions, typically associated with traumatic laryngoscopy and prolonged endotracheal intubation 5
• The respiratory system immaturity and use of oral and naso-gastric probes in prematurely born children are responsible for palatal and cranio-facial alterations 4

Dental Development and Eruption

Enamel Defects

• Generalized enamel hypoplasia affects 40-70% of preterm children in the primary dentition, likely associated with low bone mineral stores 5
• The clinical significance includes poor aesthetics and predisposition to dental caries 5

Developmental Timing

• When corrected age is considered for premature children, no delay in dental development and eruption occurs compared with full-term children 2
• Children with the lowest birthweight and shortest gestational ages have the lowest rates of dental development, particularly before six years of age 5
• The early birth of premature children must be taken into account when planning orthodontic treatment 2

Malocclusion and Orthodontic Treatment Need

Prevalence of Malocclusions

• Preterm children demonstrate a higher prevalence of malocclusion traits and greater assessed need for orthodontic treatment compared with full-term born children 3
• Moderate scientific evidence exists for more malocclusion traits among premature children 3
• Preterm infants have significantly more bilateral crossed-occlusions than term-born patients 4

Severity-Based Risk Stratification

• Very preterm and extremely preterm children have significantly more impacted teeth and higher Index of Orthodontic Treatment Need (IOTN grade 5) compared with term children 4
• Very preterm and extremely preterm births (occurring more than 8 weeks before term) represent a specific risk factor in orthodontics and a public health problem 4
• The pace of maturation is influenced by birth weight, gestational age at birth, and the degree and chronicity of neonatal illnesses 1

Clinical Management Implications

Early Identification and Monitoring

• Dental clinicians should be aware of the potential for a higher number of malocclusion traits, more malocclusion traits per individual, and greater orthodontic treatment need in prematurely born children 3
• Late-preterm infants (born between 34 and 37 weeks' gestation) are at increased risk of feeding problems, which can impact oral development 1

Functional Outcomes

• Despite increased craniofacial and dental abnormalities, prematurely born children do not have more temporomandibular disorders (TMD) or headache than full-term born children at age 8-10 years 3

Important Clinical Caveats

• The alterations in craniofacial morphology and dental development are most pronounced in extremely preterm (born before 29 weeks) and very preterm (born between 29-32 weeks) children, requiring heightened clinical vigilance 3, 4
• Infants born earlier in gestation and with more complicated medical courses tend to take longer to achieve physiologic competencies, which may compound developmental issues 1
• The economic costs of preterm birth are substantial, including immediate neonatal intensive care and ongoing long-term complex health needs 6