Palatal measurements of prematurely born, very low birth weight infants: comparison of three methods

Influence of gestational age on eruption of primary teeth in Indian children - A prospective longitudinal study

Context

Eruption of primary teeth is the most anticipated event in a child's life. Genetics, gender, socio-economic status, gestational age are a few of the determinants of the primary teeth eruption. However, the effect of gestational age on the timing of primary teeth eruption among the Indian population has not been explored to date.

Aim

The study was conducted to evaluate the influence of gestational age on time and sequence of eruption of primary teeth among children of Mysore.

Settings and Design

A prospective longitudinal cohort study design was conducted at 'Baby Oral Health Promotion Clinic' at the Department of Paediatrics, JSS Hospital, Mysore.

Methods and Material

150 newborn babies were recruited by simple random sampling and followed up from birth to 36 months. Teeth present during each visit were recorded. Data were statistically analysed and interpreted.

Statistical Analysis Used

Descriptive statistics, t-test for an independent sample, and Pearson's Chi-squared test were applied.

Results

The mandibular central incisor was the first tooth to erupt. Statistically insignificant early eruption in males was noted in both term and preterm children. When the chronological ages were compared, the preterm group showed a statistically significant delay in the eruption of all the teeth. However, when the age was adjusted for prematurity, only the central incisors and second molars showed a statistically significant delay.

Conclusions

Gestational age has a strong significant association with the eruption of primary teeth and maybe one of the strong predictors for delayed eruption among children of Mysore.

Maxillary arch dimensions in the first 6 months of life and their relationship with pacifier use

PURPOSE

This study evaluated the maxillary arch dimensions at birth and 6 months of life, and to verify the influence of pacifier use on palatal development.

METHODS

Maxillary arch impressions were taken from 80 full-term newborns, appropriate for gestational age, from 24 to 72 h of life, and repeated after 6 months. Anatomical references were mapped on dental casts and measurements were taken. Parents were questioned about feeding practices and sucking habits. Data were analysed by Kruskal-Wallis test and hierarchical mixed regression model (p < 0.05).

RESULTS

Anterior maxillary segment (median [interquartile range]) presented an increase in transverse (Δ% = 81.90 [74.40-89.70]) and in length (Δ% = 76.20 [49.10-102.70]) relative growth. No differences were detected in palatine depth from birth (11.00 mm [10.30-11.70]) to 6 months (12.60 mm [12.0-13.90]).

CONCLUSIONS

Pacifier use was positively related to the increase in anterior segment length. In the first 6 months of life, the greatest relative growth of the maxillary arch occurs in the anterior region, showing this growth does not occur homogeneously. The use of pacifiers came to influence this process, even before the eruption of the upper incisors.

Palatal development of preterm and low birthweight infants compared to term infants -- What do we know? Part 3: discussion and conclusion

BACKGROUND

It has been hypothesized that prematurity and adjunctive neonatal care is 'a priori' a risk for disturbances of palatal and orofacial development which increases the need for later orthodontic or orthognathic treatment. As results on late consequences of prematurity are consistently contradictory, the necessity exists for a fundamental analysis of existing methodologies, confounding factors, and outcomes of studies on palatal development in preterm and low birthweight infants.

METHOD

A search of the literature was conducted based on Cochrane search strategies including sources in English, German, and French. Original data were recalculated from studies which primarily dealt with both preterm and term infants. The extracted data, especially those from non-English paper sources, were provided unfiltered in tables for comparison (Parts 1 and 2).

RESULTS

Morphology assessment of the infant palate is subject to non-standardized visual and metrical measurements. Most methodologies are inadequate for measuring a three-dimensional shape. Several confounding factors were identified as causes contributing to disturbances of palatal and orofacial development.

CONCLUSION

Taking into account the abovementioned shortcomings, the following conclusions may be drawn for practitioners and prospective investigators of clinical studies. 1) The lack of uniformity in the anatomical nomenclature of the infant's palate underlines the need for a uniform definition. 2) Metrically, non-intubated preterm infants do not exhibit different palatal width or height compared to matched term infants up to the corrected age of three months. Beyond that age, no data on the subject are currently available. 3) Oral intubation does not invariably alter palatal morphology of preterm and low birthweight infants. 4) The findings on palatal grooving, height, and asymmetry as a consequence of orotracheal intubation up to the age of 11 years are inconsistent. 5) Metrically, the palates of orally intubated infants remain narrower posteriorly, beginning at the second deciduous molar, until the age of 11 years. Beyond that age, no data on the subject are currently available. 6) There is a definite need for further, especially metrical, longitudinal and controlled trials on palatal morphology of preterm and low birthweight infants with reliable measuring techniques. 7) None of the raised confounding factors for developmental disturbances may be excluded until evident results are presented. Thus, early orthodontic and logopedic control of formerly premature infants is recommended up to the late mixed dentition stage.

Palatal development of preterm and low birthweight infants compared to term infants - What do we know? Part 1: The palate of the term newborn

Background

The evidence on prematurity as 'a priori' a risk for palatal disturbances that increase the need for orthodontic or orthognathic treatment is still weak. Further well-designed clinical studies are needed. The objective of this review is to provide a fundamental analysis of methodologies, confounding factors, and outcomes of studies on palatal development. One focus of this review is the analysis of studies on the palate of the term newborn, since knowing what is 'normal' is a precondition of being able to assess abnormalities.

Methods

A search profile based on Cochrane search strategies applied to 10 medical databases was used to identify existing studies. Articles, mainly those published before 1960, were identified from hand searches in textbooks, encyclopedias, reference lists and bibliographies. Sources in English, German, and French of more than a century were included. Data for term infants were recalculated if particular information about weight, length, or maturity was given. The extracted values, especially those from non-English paper sources, were provided unfiltered for comparison.

Results

The search strategy yielded 182 articles, of which 155 articles remained for final analysis. Morphology of the term newborn's palate was of great interest in the first half of the last century. Two general methodologies were used to assess palatal morphology: visual and metrical descriptions. Most of the studies on term infants suffer from lack of reliability tests. The groove system was recognized as the distinctive feature of the infant palate. The shape of the palate of the term infant may vary considerably, both visually and metrically. Gender, race, mode of delivery, and nasal deformities were identified as causes contributing to altered palatal morphology. Until today, anatomical features of the newborn's palate are subject to a non-uniform nomenclature.

Conclusion

Today's knowledge of a newborn's 'normal' palatal morphology is based on non-standardized and limited methodologies for measuring a three-dimensional shape. This shortcoming increases bias and is the reason for contradictory research results, especially if pathologic conditions like syndromes or prematurity are involved. Adequate measurement techniques are needed and the 'normal palatal morphology' should be defined prior to new clinical studies on palatal development.

Palatal development of preterm and low birthweight infants compared to term infants - What do we know? Part 2: The palate of the preterm/low birthweight infant

Background

Well-designed clinical studies on the palatal development in preterm and low birthweight infants are desirable because the literature is characterized by contradictory results. It could be shown that knowledge about 'normal' palatal development is still weak as well (Part 1). The objective of this review is therefore to contribute a fundamental analysis of methodologies, confounding factors, and outcomes of studies on palatal development in preterm and low birthweight infants.

Methods

An electronic literature search as well as hand searches were performed based on Cochrane search strategies including sources of more than a century in English, German, and French. Original data were recalculated from studies which primarily dealt with both preterm and term infants. The extracted data, especially those from non-English paper sources, were provided unfiltered for comparison.

Results

Seventy-eight out of 155 included articles were analyzed for palatal morphology of preterm infants. Intubation, feeding tubes, feeding mode, tube characteristics, restriction of oral functions, kind of diet, cranial form and birthweight were seen as causes contributing to altered palatal morphology. Changes associated with intubation concern length, depth, width, asymmetry, crossbite, and contour of the palate. The phenomenon 'grooving' has also been described as a complication associated with oral intubation. However, this phenomenon suffers from lack of a clear-cut definition. Head flattening, pressure from the oral tube, pathologic or impaired tongue function, and broadening of the alveolar ridges adjacent to the tube have been raised as causes of 'grooving'. Metrically, the palates of intubated preterm infants remain narrower, which has been examined up to the age of the late mixed dentition.

Conclusion

There is no evidence that would justify the exclusion of any of the raised causes contributing to palatal alteration. Thus, early orthodontic and logopedic control of formerly orally intubated preterm infants is recommended, as opposed to non-intubated infants. From the orthodontic point of view, nasal intubation should be favored. The role that palatal protection plates and pressure-dispersing pads for the head have in palatal development remains unclear.

Three-dimensional morphology of the palate in subjects with isolated cleft palate at the stage of permanent dentition

OBJECTIVE

Three-dimensional analysis of palate size and shape in patients with isolated cleft palate at the stage of permanent dentition.

DESIGN

Cross-sectional study using Fourier transform profilometry.

SUBJECTS

Twenty-nine randomly selected dental casts of approximately 15-year-old boys with isolated cleft palate and 28 dental casts of normal boys of the same age.

INTERVENTIONS

All patients were operated on by the same method (pushback and pharyngeal flap surgery) at a mean age of 4.5 years.

MAIN OUTCOME MEASURES

Data on the palate height in 210 defined locations (pixels).

RESULTS

The palate in isolated clefts is narrower throughout its whole extent and lower from the level of the first premolars. The difference, as compared with controls, increases in a posterior direction. At the level of the first molars, palatal height is reduced by one-quarter, the area of the transversal section by more than one-third. The shaping of the palate vault is, on average, symmetrical with a marked interindividual variability. Palatal height does not depend on the width of the dentoalveolar arch, and the height of the primary palate is not reduced.

CONCLUSION

The smaller width and reduced height from the level of the first premolars posteriorly confirm the substantially reduced space available for the tongue in patients with isolated cleft palate. Deviations are on the average symmetrical, and the anterior part of the palate is not shallower.

Effects of preterm birth on oral growth and development

Preterm and low birthweight children comprise approximately 6 per cent of all live births. They are prone to many serious medical problems during the neonatal period which may affect the development of oral tissues. The present paper reviews the results of this author's own decade of research into the oral development of preterm children in the light of current understanding of the field. Studies have shown a high prevalence of generalized enamel hypoplasia in the primary dentition of around 40-70 per cent in preterm children which is likely to be associated with low bone mineral stores. The clinical significance of enamel defects is poor aesthetics, and predisposition of the lesions to dental caries. Other dental defects observed in preterm children are localized enamel hypoplasia, crown dilacerations, and palatal distortions which are usually associated with traumatic laryngoscopy and prolonged endotracheal intubation. Furthermore, recent studies have demonstrated that the rate of dental development, and dental eruption may be affected by preterm birth. Children with the lowest birthweight and shortest gestational ages have the lowest rates of dental development, particularly before six years of age. The results of these clinical studies may have significant implications in the dental management of preterm children.

Reduction of craniofacial and palatal narrowing in very low birthweight infants

Many infants born preterm have positional moulding of the head and palate. This study investigates whether specially designed, foam pressure dispersing pads (PDP) worn throughout the neonatal hospital course, were not only effective in reducing craniofacial flattening, but also in lessening palatal narrowing in very low birthweight (VLBW) infants. The study was conducted in two phases. Twenty-three consecutively born VLBW infants were randomly selected to act as a comparative group. The next 31 VLBW infants born comprised the intervention group, and wore PDP during hospitalization. The two groups were similar in birthweight and gestational age. The groups were compared for changes in craniofacial and palatal parameters at three time intervals during hospitalization. Results indicated a significant increase in growth of craniofacial width, palatal width and palatal area of infants wearing PDP compared to those infants not wearing them. These findings suggest that craniofacial and palatal narrowing observed in VLBW infants may be reduced by the wearing of PDP during hospitalization.