Influence of feeding and non-nutritive sucking methods on the development of the dental arches: longitudinal study of the first 18 months of life.

The purpose of this study is to examine various maxillary and mandibular dental arch parameters in 122 infants over an 18-month period. The subjects were grouped according to their feeding and sucking method as follows: 1. breast fed, 2. breast fed and functional exerciser, 3. functional nipple and exerciser, 4. conventional nipple, 5. conventional nipple and pacifier, and 6. residual group. The choice of the type of feeding, nipple, pacifier or exerciser was left totally to the parents. AbSolute and percentage changes in each dental arch parameter were calculated at each stage of development and the Repeated Measures Analysis of Variances was used for statistical comparisons of the following interactions: sex, i.e., males vs. females; time, i.e., change with growth during the 18-month period; and group, i.e., differences between the various feeding~sucking methods. Comparisons of the absolute and percentage changes in the maxillary and mandibular arch parameters indicated that no significant differences were present between the different feeding groups at the end of the 18-month p, eriod. Pediatricians, pediatric dentists and orthodontists are interested in infant feeding. Although each specialty might be interested in one aspect of child development, collectively their objective is to ensure that the infant is provided with: (1) good nutrition, (2) optimal physical growth, (3) optimal emotional growth, and (4) optimal dental and facial growth. The satisfaction that babies and young children derive from nutrient and non-nutrient sucking habits, and the need to duplicate the breast by the use of substitute sucking nipples and pacifiers has been recognized for years. Ravn (1974) reported that sucking objects appear in the literature of the late 15th and early 16th centuries. According to Winter (1980), the first comprehensive account of the sucking bag was given by Struve in 1801 who described it as a small linen bag filled with bread, milk, and sugar and which was used for the nourishment and composing of children. There are a number of conflicting opinions regarding the effects of the feeding method on the subsequent digital habit that the child practices. Yarrow (1954), Graber (1963), and Najera (1963) are opinion that bottle feeding has a significant influence on the child’s acquiring digital habits. They generally observed that breast-fed infants have the lowest prevalence of digital habits. On the other hand, Klackenberg (1949, 1971), Traisman and Traisman (1958) and Porter (1964) concluded that the method of feeding had no appreciable influence on the acquisition of digital habits. Larsson (1985) indicated that in the last 15 years there has been a decrease in the number of children with a finger sucking habit and an increase in the number of dummy suckers. Larsson (1986) in a later review explained that continuous dummy sucking in the primary dentition usually is associated with an anterior open bite and an increased prevalence of posterior crossbite. Klackenberg (1949) and Popovich and Thompson (1973) believe that the use of a pacifier for non-nutritive sucking decreases the prevalence of the infant’s acquiring a digital habit. Popovich and Thompson (1973) concluded that since digital habits increase the prevalence of malocclusion, infants should be encouraged to use a pacifier as a prophylactic measure. These contradictory opinions regarding the extent to which digitand dummy-sucking alter the dental occlusion are partly the result of the difficulty PEDIATRIC DENTISTRY: March 1987/Vol. 9 No. 1 13 in determining the precise role of any single etiologic factor in the development of malocclusions. Malocclusion and normal occlusion are not always definite and clear-cut entities, particularly in the early stages of dentofacial development. Another contributory factor is the limited number of longitudinal studies describing the changes in the dental arches in infants fed with different methods. During the last 25 years different types of nipples and pacifiers have been introduced for feeding as well as satisfying the sucking reflex in infants. In general, these nipples and pacifiers are described as being 1 of 2 types: "functional" and "conventional." The major differences between the 2 types is their size and shape in addition to their purported effects on the development of the oral structures. Very little scientific data are presently available to substantiate the desirability of one design over another. The objective of this study was to examine the changes in the dental arch parameters during the first 18 months in 122 children. The children were grouped according to the types of nipples and pacifiers used into the following 6 groups: 1. breast fed, 2. breast fed and functional exerciser, 3. functional nipple and functional pacifier, a 4. conventional nipple and no pacifier, 5. conventional nipple and conventional pacifier, b and 6. residual group. This last group included individuals that frequently changed their feeding and sucking habits and hence could not be properly classified in any of the other 5 groups. Methods and Materials The Subjects The infants were recruited from the obstetric and pediatric departments at the University of Iowa Hospitals and Clinics and private pediatric practices in Iowa City, Iowa. The only criteria for selecting the infants for the study were: (a) healthy full-term babies with no apparent congenital anomalies, and (b) availability of the family for evaluation over an 8-year period. Because longitudinal studies frequently are hampered by the difficulty in retaining the participants for an extended period of time, an attempt was made to recruit parents with a strong commitment to the completion of the program. The recruiting effort extended over a 2-year period at the end of which 135 infants and their families were enrolled in the project. The combination of monetary rewards, and the knowledge that routine dental examinations would be provided free of charge, produced committed participants. At 24 months, 122 Nuk Nipple and Exerciser--Reliance Products Corp. PEr Orthodontic Nipple and Infa. Gerber--Evenflo Products Co, International Playtex. C