The aim of the study was to evaluate in a three-dimensional manner the dentoskeletàl changes after slow maxillary expansion. The sample consisted of 34 children with a unilateral, symmetrical posterior cross-bite. Half of the children were treated with a quad-helix and the rest with a removable appliance. Assessment of the changes was made with study casts, and frontal and lateral cephalograms, before treatment, at the end of the expansion, after a retention period of 3 months, and after a post-retention period of 3 months. The results showed that sufficient expansion of the dental arches took place in both groups. The expansion expressed in the molar region in the quad-helix group was mostly due to buccal translation of the teeth and in the removable appliance group due to buccal tipping. The quad-helix group showed somewhat greater basal expansion than the removable appliance group, though the basal expansion in both groups was rather small. A tendency towards an increase of the NL/ML angle characterized the removable appliance group, but the opposite pattern was present in the quad-helix group.
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References
1.
AthanasiouA. E., MazaheriM. and ZarrinniaK. (1988) Dental arch dimensions in patients with unilateral cleft lip and palate, Cleft Palate Journal, 25, 139–145.
2.
AthanasiouA. E., TsengC. Y., ZarrinniaK. and MazaheriM. (1990) Frontal cephalometric study of transverse dentofacial growth in children with bilateral cleft of lip, alveolus and palate. Journal of Cranio-Maxillo-Facial Surgery, 18, 49–54.
3.
AthanasiouA. E., MoyersR. E., MazaheriM. and Toutount-zakisN. (in press) Frontal cephalometric evaluation of transverse dentofacial morphology and growth in children with isolated cleft palate. Journal of Cranio-Maxillo-Facial Surgery.
4.
BellR. A. and LeCompteE. J. (1981) The effects of maxillary expansion using a quad-helix appliance during the deciduous and mixed dentitions, American Journal of Orthodontics, 79, 152–161.
5.
BellR. A. (1982) A review of maxillary expansion in relation to rate of expansion and patients age, American Journal of Orthodontics, 81, 32–37.
6.
BjörkA. and SkiellerV. (1977) Growth of the maxilla in three dimensions as revealed radiographically by the implant method, British Journal of Orthodontics, 4, 53–64.
7.
BoysenB. and la CourK. (1991) Evaluation of the changes in facial skeleton, soft-tissue profile and dental arch dimensions after posterior crossbite correction by quad-helix and a removable appliance, Thesis, Royal Dental College, Aarhus.
8.
BroadbentB. H.Sr, BroadbentB. H.Jr and GoldenW. H. (1975) Bolton Standards of Dentofacial Developmental Growth, CV Mosby Co., St Louis.
9.
ChaconasS. J. and de Alba y LevyJ. A. (1977) Orthopedic and orthodontic applications of the quad-helix appliance, American Journal of Orthodontics, 72, 422–428.
10.
CottonL. A. (1978) Slow maxillary expansion: Skeletal versus dental response to low magnitude force in Macaca Mulata, American Journal of Orthodontics, 73, 1–23.
11.
EkströmC., HenriksonC. and JensenR. (1977) Mineralisation in the midpalatal suture after orthodontic expansion, American Journal of Orthodontics, 71, 449–455.
12.
FicarelliJ. P. (1978) A brief review of maxillary expansion. Journal of Pedodontics, 3, 29–35.
13.
HaasA. J. (1961) Rapid expansion of maxillary dental arch and nasal cavity by opening the midpalatal suture. Angle Orthodontist, 31, 73–91.
14.
HaasA. J. (1970) Palatal expansion—Just the beginning of dentofacial orthopedics, American Journal of Orthodontics, 57, 219–255.
15.
HelmS. (1968) Malocclusion in Danish children with adolescent dentition: An epidemiologic study, American Journal of Orthodontics, 54, 352–366.
16.
HermansonH., KurolJ. and RonnermanA. (1985) Treatment of unilateral crossbite with quad-helix and removable plates, European Journal of Orthodontics, 7, 97–102.
17.
HicksE. P. (1978) Slow maxillary expansion, American Journal of Orthodontics, 73, 121–141.
18.
KrebsA. (1959) Expansion of the midpalatal suture studied by means of metallic implants, Acta Odontologica Scandinavica, 17, 491–501.
19.
KrebsA. (1964) Midpalatal suture expansion studied by the implant method over a seven-year period, Transactions of European Orthodontic Society, 131–142.
20.
LindnerA. J., HenriksonC. O., OdenrickL. and ModeerT. (1986) Maxillary expansion of unilateral crossbite in preschool children, Scandinavian Journal of Dental Research, 94, 411–418.
21.
MoorreesC. F. A. (1959) The Dentition of the Growing Child: a Longitudinal Study of Dental Development Between 3 and 18 Years of Age, Harvard University Press, Cambridge, Mass.
22.
Mossaz-JoelsonK. and MossazC. F. (1989) Slow maxillary expansion: a comparison between banded and bonded appliances. European Journal of Orthodontics, 11, 67–76.
23.
MoyersR. E. (1988) Handbook of Orthodontics, Year Book of Medical Publications, Chicago.
24.
MoyersR. E. and JayP. (1959) Orthodontics in Mid-century: Transactions of a Workshop in orthodontics at the University of Michigan, Mosby Co., St. Louis.
25.
NieN. H., HullC. H., JenkinsJ. G., SteinbrennerK. and BentD. H. (1975) Statistical Package for the Social Sciences, McGraw Hill Book Co., New York.
26.
RantaR. (1988) Treatment of unilateral posterior crossbite: comparison of the quad-helix and removable plate, Journal of Dentistry for Children, 55, 102–104.
27.
SkiellerV. (1964) Expansion of the midpalatal suture by removable plates, analysed by the implant method, Transactions of European Orthodontic Society, 143–157.
28.
StoreyA. (1973) Tissue response to the movement of bones, American Journal of Orthodontics, 64, 229–247.
29.
ThilanderB., WahlundS. and LennartsonB. (1984) The effect of early interceptive treatment in children with posterior crossbite, European Journal of Orthodontics, 6, 25–34.
30.
WertzR. A. (1970) Skeletal and dental changes accompanying rapid midpalatal suture opening, American Journal of Orthodontics, 58, 41–66.
