Malocclusion in the primary dentition in children with and without deformational plagiocephaly

Helmet therapy efficacy and its prediction in Japanese infants with positional plagio- and brachycephaly

PURPOSE

To provide additional information on optimal start times and therapeutic effectiveness based on treatment outcome of Japanese infants with positional plagio- and brachycephaly (PPB) receiving cranial molding helmet therapy (CMHT).

METHODS

In this retrospective cohort study, data from a 3D head scanning system was analyzed from 2173 Japanese infants who completed CMHT. Anterior and posterior symmetry ratio (ASR and PSR) and longitudinal to transverse diagonal ratios (LD/TDR) were calculated based on skull shape at helmet design and at completion of therapy. The outcomes were evaluated using the regression analysis and a predictive model using cranial parameters was developed.

RESULTS

The earlier the start of therapy, the greater the therapeutic effect on ASR, PSR, and LD/TDR (ASR, -0.134 percent points (ppt)/day; PSR, -0.086 ppt/day; and LD/TDR, -0.131 ppt/day). In the predictive model, in addition to starting age of the therapy, sex (male), the degree of deformity of the head (DoD) (moderate and severe), quadrant volume, PSR, and head circumference at the start of treatment also had a positive effect on changes in ASR, DoD (moderate and severe), ASR, LD/TDR and transverse diameter for PSR, sex (male), DoD (moderate), quadrant volume, PSR, and head circumference for LD/TDR.

CONCLUSION

The starting age of therapy had a relatively smaller contribution to outcome effects. Applying the cranial parameter obtained at the start of treatment to the predictive model helps to predict the effect of CMHT and whether PPB can be treated with CMHT in infants of older age.

Incompetent lip seal and nail biting as risk factors for malocclusion in Japanese preschool children aged 3-6 years

BACKGROUND

Malocclusion is a multifactorial condition associated with genetic and environmental factors. The purpose of this study was to investigate the prevalence of occlusal traits, oral habits, and nose and throat conditions by age and to assess the association between malocclusion and its environmental factors in Japanese preschool children.

METHODS

A total of 503 Japanese children (258 boys and 245 girls aged 3-6 years) were recruited. Occlusal traits were assessed visually to record sagittal, vertical, and transverse malocclusion, and space discrepancies. Lip seal was recorded by an examiner, and oral habits (finger sucking, lip sucking or lip biting, nail biting, chin resting on a hand) and nose and throat conditions (tendency for nasal obstruction, allergic rhinitis, palatine tonsil hypertrophy) were assessed by a questionnaire completed by the parents. The prevalence of each item was calculated, and binary logistic regression was used to examine the factors related to malocclusion.

RESULTS

62.0% of preschool children in the present study exhibited malocclusion, and 27.8% exhibited incompetent lip seal. Nail biting was the most frequent oral habit with a prevalence of 18.9%. Nasal obstruction was recorded in 30.4% of children. The results of binary logistic regression showed that incompetent lip seal was significantly related to malocclusion, and that nail biting was significantly negatively related.

CONCLUSIONS

Incompetent lip seal is significantly associated with malocclusion, but nail biting may not necessarily be a deleterious habit for the occlusion in Japanese preschool children.

Comparison of molding helmet therapy versus natural course in twins with nonsynostotic head deformation

This observational study aims to compare the effectiveness of helmet therapy versus natural course in twin siblings suffering from nonsynostotic head deformations. A retrospective analysis of all twin couples treated with helmet therapy between March 2009 and May 2017 at an orthopedic hospital was conducted. Inclusion criteria were me if only one twin received helmet therapy. The other twin acted as control. A classification for different head shapes was used. A total of 61 twin couples was included. Change in outcome parameters of helmet therapy and natural course differed significantly: cranial vault asymmetry (CVA) -0.66 cm vs. -0.04 cm, cranial vault asymmetry index (CVAI) -5.35% vs. -0.51% (both p < 0.001), cephalic index (CI) -3.10% vs. -1.91% (p = 0.006). Helmet therapy showed a success rate (CI < 90% and CVAI ≤7% or better) of 63.6% vs. 21.1% in children with natural course (p = 0.002). Within the limitations of the study it seems that the results of this retrospective, single-center study confirm that helmet therapy to be a reliable treatment for mild to severe positional head deformation.

Denominator of Cranial Vault Asymmetry Index: Choosing Between Longer and Shorter Diagonal Lengths

Since it was proposed in this journal in 2001, the cranial vault asymmetry index (CVAI) has been an important parameter for assessing cranial shape. However, different publications currently use different variables in the denominator of the CVAI formula. We thus investigated the use of long and short diagonal lengths as variables in the denominator of the CVAI formula. We searched the databases of PubMed, Google Scholar, and Scopus for articles published between 2016 and 2022 that cited the original work article of CVAI. Articles were included if they were written in English and if the denominator of the CVAI formula was specified. For multiple articles by the same author, only the most recent article was included. In total, 30 articles were included; 10 articles used the longer diagonal length as the denominator and 20 articles used the shorter diagonal length. No uniform trend was observed by a country or journal of publication. Application of the CVAI formula using different denominators yielded interchangeable results, and the resulting values had only negligible differences clinically. However, it would be necessary to create a standard formula for using the CVAI as a parameter for reporting cranial shape assessments consistently.

Facial asymmetry in children with either unilateral lambdoid craniosynostosis or positional posterior plagiocephaly

BACKGROUND

In unilateral lambdoid craniosynostosis (ULC), the posteriorly situated lambdoid suture of the cranial vault fuses prematurely. Positional posterior plagiocephaly (PPP) causes flattening of the posterior side of the head, either through external forces or through underlying differences in brain development. Both conditions cause occipital flattening of the head, but the aetiology is different.

MATERIALS AND METHODS

Eight ULC children were compared with 16 sex- and age-matched PPP children. 3D computer tomography scans of all 24 children were analysed with Dolphin imaging software. The location and symmetry of the temporomandibular joint (Co), and the symmetry of the maxillary anterior nasal spine (ANS) and the mandibular symphysis (Pgn) were analysed. Furthermore, the mandibular bone (Co-Pgn) length, corpus length, ramus height, positional changes in the external acoustic meatus (PoL) and the distance from the orbital margin to the articular fossa were measured.

RESULTS

In all eight ULC children, the Co was anteriorly displaced on the affected side compared with the unaffected side. In all ULC and PPP children, the ANS, which is considered the bony maxillary midpoint, was shifted towards the affected side. In all ULC children, the mandibular bone (Co-Pgn) was shorter on the affected side. The PoL was antero-inferiorly positioned in all ULC children on the affected side compared with the unaffected side.

CONCLUSIONS

Our results show that both types of posterior plagiocephaly are associated with an asymmetric position of the Co and asymmetry of the mandible and maxilla. Facial asymmetry was more frequently seen in ULC than PPP children.

Relationship between Dental Occlusion and Maximum Tongue Pressure in Preschool Children Aged 4-6 Years

Tongue function is regarded as a primary factor in the etiology of malocclusion, but details of the relationship remain unknown. The purpose of the present study was to investigate maximum tongue pressure, in preschool children to examine its relationship with dental occlusion. A total of 477 healthy children (248 boys, 229 girls, aged 4-6 years) were recruited. Dental occlusion was assessed visually to record sagittal, vertical, and transverse malocclusion, and space discrepancies. Maximum tongue pressure was measured using a balloon-based tongue pressure measurement device. Additionally, 72 children (37 boys, 35 girls, aged 4-5 years) were recruited for a 1-year follow-up study. Approximately half of the children (53.5%) showed some type of malocclusion in the present study. Maximum tongue pressure was highest in the 6-year-old children. The results of a two-way ANCOVA show that the effect of age was significant (p < 0.001); however, the effects of sex and dental occlusion, or the interactions among these variables, did not reach significance. Additionally, maximum tongue pressure increased significantly in the 1-year follow-up study (p < 0.001), especially in the normal occlusion group. Maximum tongue pressure increases markedly with growth in the preschool years and can be associated with some types of malocclusion in preschool children.

Stereophotogrammetric head shape assessment in neonates is feasible and can identify distinct differences between term-born and very preterm infants at term equivalent age

The development of head shape and volume may reflect neurodevelopmental outcome and therefore is of paramount importance in neonatal care. Here, we compare head morphology in 25 very preterm infants with a birth weight of below 1500 g and / or a gestational age (GA) before 32 completed weeks to 25 term infants with a GA of 37–42 weeks at term equivalent age (TEA) and identify possible risk factors for non-synostotic head shape deformities. For three-dimensional head assessments, a portable stereophotogrammetric device was used. The most common and distinct head shape deformity in preterm infants was dolichocephaly. Severity of dolichocephaly correlated with GA and body weight at TEA but not with other factors such as neonatal morbidity, sex or total duration of respiratory support. Head circumference (HC) and cranial volume (CV) were not significantly different between the preterm and term infant group. Digitally measured HC and the CV significantly correlated even in infants with head shape deformities. Our study shows that stereophotogrammetric head assessment is feasible in all preterm and term infants and provides valuable information on volumetry and comprehensive head shape characteristics. In a small sample of preterm infants, body weight at TEA was identified as a specific risk factor for the development of dolichocephaly.

Effectiveness of pediatric integrative manual therapy in cervical movement limitation in infants with positional plagiocephaly: a randomized controlled trial

BACKGROUND

Positional plagiocephaly (PP) is a cranial deformation frequent amongst children and consisting in a flattened and asymmetrical head shape. PP is associated with excessive time in supine and with congenital muscular torticollis (CMT). Few studies have evaluated the efficiency of a manual therapy approach in PP. The purpose of this parallel randomized controlled trial is to compare the effectiveness of adding a manual therapy approach to a caregiver education program focusing on active rotation range of motion (AROM) and neuromotor development in a PP pediatric sample.

METHODS

Thirty-four children with PP and less than 28 week-old were randomly distributed into two groups. AROM and neuromotor development with Alberta Infant Motor Scale (AIMS) were measured. The evaluation was performed by an examiner, blinded to the randomization of the subjects. A pediatric integrative manual therapy (PIMT) group received 10-sessions involving manual therapy and a caregiver education program. Manual therapy was addressed to the upper cervical spine to mobilize the occiput, atlas and axis. The caregiver educational program consisted in exercises to reduce the positional preference and to stimulate motor development. The control group received the caregiver education program exclusively. To compare intervention effectiveness across the groups, improvement indexes of AROM and AIMS were calculated using the difference of the final measurement values minus the baseline measurement values. If the distribution was normal, the improvement indexes were compared using the Student t-test for independent samples; if not, the Mann-Whitney U test was used. The effect size of the interventions was calculated using Cohen's d.

RESULTS

All randomized subjects were analysed. After the intervention, the PIMT group showed a significantly higher increase in rotation (29.68 ± 18.41°) than the control group (6.13 ± 17.69°) (p = 0.001). Both groups improved the neuromotor development but no statistically significant differences were found. No harm was reported during the study.

CONCLUSION

The PIMT intervention program was more effective in increasing AROM than using only a caregiver education program. The study has been retrospectively registered at clinicaltrials.gov, with identification number NCT03659032 . Registration date: September 1, 2018.

Significant Factors in Cranial Remolding Orthotic Treatment of Asymmetrical Brachycephaly

This retrospective chart review focuses on determining the most effective time to begin cranial remolding orthosis (CRO) treatment for infants with asymmetrical brachycephaly. Subjects with asymmetrical brachycephaly started CRO treatment between 3 and 18 months of age. These infants had a cranial vault asymmetry index (CVAI) ≥ 3.5 and a cranial index (CI) ≥ 90. Subjects were excluded if they had any comorbidities affecting growth, dropped out of treatment, were lost to follow-up, or were noncompliant. Factors which were found to statistically influence treatment outcomes were subject initial age, initial CVAI, and initial CI. Overall, younger subjects were more likely to achieve a corrected head shape. The presence of prematurity or torticollis had statistically nonsignificant effects on the success of treatment. Initial CI was found to be a stronger predictor than initial CVAI as to which subjects achieved correction. The less severe the starting CI, the more likely the subject was to achieve full correction. The clinical understanding is that it requires more cranial growth to “round out” a full posterior skull flattening than an asymmetry. Based on the study results, infants with asymmetrical brachycephaly should be treated as early as possible to increase chances of achieving full correction of the deformity.

Craniofacial Asymmetry from One to Three Years of Age: A Prospective Cohort Study with 3D Imaging

Deformational plagiocephaly (DP) is considered a risk factor for facial asymmetry. This cohort-based, prospective, follow-up study used three-dimensional (3D) stereophotogrammetry to assess the development of facial asymmetry in a normal birth cohort and to investigate the impact of DP on facial asymmetry for the age range of one to three years. The study sample consisted of 75 children: 35 girls (47%) and 40 (53%) boys recruited from Oulu University Hospital. A total of 23 (31%) subjects had a history of DP in infancy. 3D facial images were obtained at the mean (SD) age of 1.01 (0.04) year old at T1 and 3.02 (0.14) years old at T2. To determine facial asymmetry, both landmark-based and surface-based facial symmetry methods were used. As measured with the surface-based methods, upper facial symmetry improved from T1 to T2 (p < 0.05). As measured with the landmark-based methods, facial symmetry improved on the upper and lower jaw from T1 to T2 (p < 0.05). The asymmetric effect of DP on the upper parts of the face tends to correct spontaneously during growth. Results indicate that previous DP does not seem to transfer to facial or occlusal asymmetry at the age of three years old.

Head orthosis therapy in positional plagiocephaly: longitudinal 3D-investigation of long-term outcomes, compared with untreated infants and with a control group

Background

As there are very few long-term studies on the effects of head orthosis on deformational plagiocephaly (DP), we investigated the outcomes of patients, including facial symmetry and dental occlusion.

Methods

Forty-five infants with DP [cranial vault asymmetry index (CVAI) > 3.5 per cent] were divided into two groups: one treated with head orthosis (32 infants) and another without (13 infants). Another group without head asymmetry (CVAI ≤ 3.5 per cent) served as control. Using 3D-stereophotogrammetry, cranial asymmetry was analysed using symmetry-related variables [CVAI, posterior cranial asymmetry index (PCAI), and ear offset]. Data acquisition was performed before (T1) and at the end of treatment (T2), and at the age of 4 years (T3) for the treated group and at T1 and T3 for the remaining groups. Parameters of facial symmetry and dental occlusion were assessed at T3 for infants with DP.

Results

Symmetry-related variables (∆T1-T3) improved significantly more in the treated than the control group, whereas these parameters did not differ significantly between the untreated and control group. Comparing the treated and untreated groups between T1 and T3, the reduction in the asymmetry at the treated group was significantly higher for the CVAI and PCAI. In follow-up, the untreated group showed higher incidences of facial asymmetries than the treated group. Seventy-five per cent of all lateral crossbites found in patients with DP were contralateral to the posterior flattening.

Limitations

Due to ethical reasons, the investigation is a non-randomized study. Parameters of facial symmetry were only assed for the treated and untreated groups.

Conclusion

Head orthosis therapy in patients with DP leads to significantly better long-term outcomes. Facial asymmetries are more frequent in patients with DP who do not receive this treatment.

Helmet Treatment of Infants With Deformational Brachycephaly

Deformation of the cranium in infancy represents a spectrum of deformity, ranging from severe asymmetric yet proportional distortion of the skull in plagiocephaly, to nearly symmetric yet disproportional distortion in brachycephaly. As such, the condition is best described as deformational plagiocephaly-brachycephaly with isolated plagiocephaly and/or isolated brachycephaly being at either ends of the spectrum. Due to its symmetric appearance, deformational brachycephaly is often incorrectly dismissed as being less concerning, and it has sometimes erroneously been reported that brachycephaly cannot be treated successfully with a cranial orthosis. We prospectively report on 4205 infants with isolated deformational brachycephaly treated with a cranial orthosis from 2013 to 2017. These results demonstrate that the orthosis is successful in the treatment of deformational brachycephaly with an 81.4% improvement toward normal (95.0 to 89.4) in cephalic index. We furthermore demonstrate that entrance age influences treatment results, with younger infants demonstrating both improved outcomes and shorter treatment times.

Facial asymmetry correction with moulded helmet therapy in infants with deformational skull base plagiocephaly

PURPOSE

The recommendation issued by the American Academy of Pediatrics in the early 1990s to position infants on their back during sleep to prevent sudden infant death syndrome (SIDS) has dramatically reduced the number of deaths due to SIDS but has also markedly increased the prevalence of positional skull deformation in infants. Deformation of the base of the skull occurs predominantly in very severe deformational plagiocephaly and is accompanied by facial asymmetry, as well as an altered ear position, called ear shift. Moulded helmet therapy has become an accepted treatment strategy for infants with deformational plagiocephaly. The aim of this study was to determine whether facial asymmetry could be corrected by moulded helmet therapy.

MATERIALS AND METHODS

In this retrospective, single-centre study, we analysed facial asymmetry of 71 infants with severe deformational plagiocephaly with or without deformational brachycephaly who were undergoing moulded helmet therapy between 2009 and 2013. Computer-assisted, three-dimensional, soft-tissue photographic scanning was used to record the head shape before and after moulded helmet therapy. The distance between two landmarks in the midline of the face (i.e., root of the nose and nasal septum) and the right and left tragus were measured on computer-generated indirect and objective 3D photogrammetry images. A quotient was calculated between the two right- and left-sided distances to the midline. Quotients were compared before and after moulded helmet therapy. Infants without any therapy served as a control group.

RESULTS

The median age of the infants before onset of moulded helmet therapy was 5 months (range 3-16 months). The median duration of moulded helmet therapy was 5 months (range 1-16 months). Comparison of the pre- and post-treatment quotients of the left vs. right distances measured between the tragus and root of the nose (n = 71) and nasal septum (n = 71) revealed a significant reduction of the asymmetry (Tragus-Nasion-Line Quotient: 0.045-0.022; p < 0.0001; Tragus-Subnasale-Line Quotient: 0.045-0.021; p < 0.0001). The control group without treatment showed no significant change in the quotient (Tragus-Nasion-Line Quotient no helmet: 0.049-0.055/Tragus-Subnasale-Line Quotient no helmet: 0.039-0.055).

CONCLUSION

Moulded helmet therapy can correct facial symmetry in infants with deformational plagiocephaly and associated facial and basal skull asymmetry.

Positional Skull Deformities

BACKGROUND

Especially in the first 6 months of life, skull deformities manifesting as a uni- or bilateral flattening of the occiput often give rise to questions of differential diagnosis and potential treatment. In this review, the authors summarize the current understanding of risk factors for this condition, and the current state of the relevant diagnostic assessment and options for treatment.

METHODS

The recommendations given in this selective review of the literature are based on current studies and on existing guidelines on the prevention of sudden infant death, the recommendations of the German Society for Pediatric Neurology (Deutsche Gesellschaft für Neuropädiatrie), and the American guidelines on the treatment of positional plagiocephaly in infancy.

RESULTS

Pre-, peri-, and postnatal risk factors can contribute to the development of positional skull deformities. These deformities can be diagnosed and classified on the basis of their clinical features, supplemented in unclear cases by ultrasonography of the cranial sutures. The putative relationship between positional skull deformities and developmental delay is currently debated. The main preventive and therapeutic measure is parent education to foster correct positioning habits (turning of the infant to the less favored side; prone positioning on occasion when awake) and beneficial stimulation of the infant (to promote lying on the less favored side). If the range of motion of the head is limited, physiotherapy is an effective additional measure. In severe or refractory cases, a skull orthosis (splint) may be useful.

CONCLUSION

The parents of children with positional skull deformities should be comprehensively informed about the necessary preventive and therapeutic measures. Treatment should be initiated early and provided in graded fashion, according to the degree of severity of the problem. Parental concern about the deformity should not be allowed to lead to a rejection of the reasonable recommendation for a supine sleeping position.