Permanent tooth agenesis in individuals with non-syndromic Robin sequence: a systematic review and meta-analysis

Dental outcomes after neonatal mandibular distraction

PURPOSE OF REVIEW

The aim of this study was to understand dental complications associated with neonatal mandibular distraction and subsequent dental outcomes.

RECENT FINDINGS

Dental injury is often associated with neonatal mandibular distraction osteogenesis. Newer technology offers safer techniques to minimize this risk. Long-term follow up and dental outcomes in permanent dentition are needed to better understand the actual risk associated with the procedure.

SUMMARY

Surgeons performing neonatal mandibular distraction osteogenesis need to understand the associated risks to deciduous and permanent dentition as well as techniques to mitigate this risk.

Characterization of phenotypes and predominant skeletodental patterns in pre-adolescent patients with Pierre-Robin sequence

Objective

To investigate the phenotypes and predominant skeletodental pattern in pre-adolescent patients with Pierre–Robin sequence (PRS).

Methods

The samples consisted of 26 Korean pre-adolescent PRS patients (11 boys and 15 girls; mean age at the investigation, 9.20 years) treated at the Department of Orthodontics, Seoul National University Dental Hospital between 1998 and 2019. Dental phenotypes, oral manifestation, cephalometric variables, and associated anomalies were investigated and statistically analyzed.

Results

Congenitally missing teeth (CMT) were found in 34.6% of the patients (n = 9/26, 20 teeth, 2.22 teeth per patient) with 55.5% (n = 5/9) exhibiting bilaterally symmetric missing pattern. The mandibular incisors were the most common CMT (n = 11/20). Predominant skeletodental patterns included Class II relationship (57.7%), posteriorly positioned maxilla (76.9%) and mandible (92.3%), hyper-divergent pattern (92.3%), high gonial angle (65.4%), small mandibular body length to anterior cranial base ratio (65.4%), linguoversion of the maxillary incisors (76.9%), and linguoversion of the mandibular incisors (80.8%). Incomplete cleft palate (CP) of hard palate with complete CP of soft palate (61.5%) was the most frequently observed, followed by complete CP of hard and soft palate (19.2%) and CP of soft palate (19.2%) (p < 0.05). However, CP severity did not show a significant correlation with any cephalometric variables except incisor mandibular plane angle (p < 0.05). Five craniofacial and 15 extra-craniofacial anomalies were observed (53.8% patients); this implicated the need of routine screening.

Conclusions

The results might provide primary data for individualized diagnosis and treatment planning for pre-adolescent PRS patients despite a single institution-based data.

A Retrospective Longitudinal Treatment Review of Multidisciplinary Interventions in Nonsyndromic Robin Sequence With Cleft Palate

Objective:

To document and analyze the overall longitudinal institutional treatment experience of children with nonsyndromic Robin sequence (RS) from infancy to early adulthood.

Design:

Retrospective longitudinal treatment review.

Setting:

A tertiary-care, referral, teaching hospital.

Patients:

Children with nonsyndromic RS and cleft palate (N = 117) born between December, 1985, and January, 2012.

Interventions:

Data regarding airway management, nutritional management, audiological interventions, orthodontic treatment, and surgical interventions were documented and analyzed in different growth/developmental stages. Comparative data from other international centers were collected from the literature.

Results:

Airway management during infancy involved prone positioning (92%), nasopharyngeal airway (6%), tracheostomy (2%), and mandibular distraction osteogenesis (1%). Feeding with nasogastric, gastrostomy, and/or gastrojejunostomy tubes was used in 44%, Haberman feeders in 53%, and Mead Johnson feeders in 3%. Gastroesophageal reflux disease was documented in 6% of the sample. During childhood and early adolescent years, pharyngeal flap surgery was carried out in 22% of the children, while 11% had secondary palatal surgery. Audiological management included the use of tympanostomy tubes in 62%, with several children needing multiple tube replacements. At least 18% were diagnosed with obstructive sleep apnea. Adenoidectomy or adenotonsillectomy was undertaken in 4%. Analysis of data pertaining to middle childhood and adolescent years showed that orthodontic treatment was conducted for most children for crowding, tooth agenesis, and skeletal and/or dental dysplasia. Orthognathic surgery frequency (<18%) was low.

Conclusions:

Institutional treatment experience of children with nonsyndromic RS involves multidisciplinary care at different ages and stages of their development.

How Does Hypodontia Compare in Nonsyndromic Pierre Robin Sequence Versus Isolated Cleft Palate and Isolated Cleft Lip?

OBJECTIVE

To assess the prevalence and patterns of hypodontia in nonsyndromic Pierre Robin sequence (PRS) and compare it with hypodontia in nonsyndromic isolated cleft palates and isolated cleft lips.

DESIGN

Retrospective cohort study.

SETTING

Alder Hey Children's Hospital, United Kingdom.

PATIENTS

Patients with nonsyndromic PRS (group 1), isolated cleft palate (group 2), and isolated cleft lip (group 3).

MAIN OUTCOME MEASURES

Hypodontia in the permanent dentition assessed from orthopantomographs.

RESULTS

A total of 154 patients were included. Group 1 had the highest incidence of hypodontia with 47% having at least one tooth congenitally absent. Groups 2 and 3 had reduced rates of hypodontia with 27% and 19% of the groups missing teeth, respectively; 93% of cases of hypodontia in group 1 involved the absence of at least one second premolar. Of these patients, there was found to be bilateral agenesis of second premolars in 50% of cases.

CONCLUSIONS

Patients with PRS and cleft palates are more likely to have hypodontia than those with isolated cleft palates or unilateral cleft lips. Patients with PRS have more severe hypodontia than those with isolated cleft palates or unilateral cleft lips. Bilateral agenesis of lower second premolars is a commonly seen pattern among patients with PRS. In this large UK study, a similar prevalence and pattern of hypodontia to other nonsyndromic PRS populations worldwide has been demonstrated.