Quantitative effects of a nickel-titanium palatal expander on skeletal and dental structures in the primary and mixed dentition: a preliminary study.
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The present study analysed the six-month effects of a nickel-titanium (NiTi) palatal expander on the dental and palatal structures of four primary (mean age 5.8 years) and nine mixed dentition children (mean age 8.7 years), with a posterior unilateral crossbite. Standardized dental and palatal landmarks were digitized using a three-dimensional (3D) electromagnetic instrument. Collected data were analysed with geometric-mathematical models. During a six-month interval, the natural growth and development of the dental arches and hard tissue palate was negligible, as assessed in seven control children (two in the primary dentition, mean age 4.4 years; five in the mixed dentition, mean age 7.7 years). In all children the crossbite was completely corrected. Indeed, dental expansion was always more than or corresponded to the palatal expansion. A smoothing of the size-independent (shape) palatal curvature in the transverse plane was observed. No differences in maximum palatal height were noted. Symmetrical derotation of the anchorage teeth in a distal direction occurred in almost all children. The inclination of the facial axis of the clinical crown (FACC) in the anatomical transverse plane of those teeth with differences between dental and palatal expansion always showed significant modifications (vestibular inclination up to 16.7 degrees). The clinical crown height of anchorage teeth remained nearly the same in all patients. No significant modifications in mandibular arch size were observed. The increase in maxillary arch width, especially in younger children, was probably due to a combination of different effects: opening of the midpalatal suture, tipping of the alveolar process, and molar tipping. (+info)
OBSERVATION OF CHILDREN'S TEETH AS A DIAGNOSTIC AID: A REVIEW. I. DENTITION IN THE ASSESSMENT OF DEVELOPMENT.
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The accuracy of information obtained from such a simple procedure as looking in the mouth as a measure of child development led to this review. The relationship between dental and physical development has been known for many years. Methods of assessing maturity by counting erupted teeth are described. Measurements taken on two boys illustrated this hypothesis, and from these the close correlation between height and weight, bone age and dental age is shown. It is suggested that physicians and dentists should record the number of erupted teeth on interval examinations, since the pattern of eruption and calcification of teeth may present the first indication of developmental retardation. (+info)
FLUID INTAKE PATTERNS OF 6-YEAR-OLD CHILDREN IN A NORTHERN FLUORIDATED COMMUNITY.
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The quantity of various fluids ingested in winter by 160 six-year-old children living in a northern climate (54 degrees N.) was surveyed as part of a study to determine whether the amount of dental decay was related to the amount of fluoridated water ingested. Only milk, water and fruit juices were found to be important sources of dietary fluid. Total fluids ingested ranged from 11.7 to 91.0 oz. per day, whereas milk intake varied from 3.1 to 52.0 oz. and water intake from 0 to 29.0 oz. per day. Twenty-four children did not drink water as such. The results, when compared with previous reports, indicate that a greater quantitative and qualitative variation in ingested fluids may occur in cool climates, possibly owing to the absence of a constant fluid demand imposed by evaporation for body cooling. Further elucidation of these differences could influence the vehicle and dosage of nutritional supplements to dietary fluids. (+info)
Identification of sources of lead in children in a primary zinc-lead smelter environment.
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We compared high-precision lead isotopic ratios in deciduous teeth and environmental samples to evaluate sources of lead in 10 children from six houses in a primary zinc-lead smelter community at North Lake Macquarie, New South Wales, Australia. Teeth were sectioned to allow identification of lead exposure in utero and in early childhood. Blood lead levels in the children ranged from 10 to 42 micro g/dL and remained elevated for a number of years. For most children, only a small contribution to tooth lead can be attributed to gasoline and paint sources. In one child with a blood lead concentration of 19.7 microg/dL, paint could account for about 45% of lead in her blood. Comparison of isotopic ratios of tooth lead levels with those from vacuum cleaner dust, dust-fall accumulation, surface wipes, ceiling (attic) dust, and an estimation of the smelter emissions indicates that from approximately 55 to 100% of lead could be derived from the smelter. For a blood sample from another child, > 90% of lead could be derived from the smelter. We found varying amounts of in utero-derived lead in the teeth. Despite the contaminated environment and high blood lead concentrations in the children, the levels of lead in the teeth are surprisingly low compared with those measured in children from other lead mining and smelting communities. (+info)
Outcomes of vital primary incisor ferric sulfate pulpotomy and root canal therapy.
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PURPOSE: To compare ferric sulfate (FS) pulpotomy and primary tooth root canal therapy (RCT) in cariously exposed vital pulps of primary incisors. METHODS: A total of 133 incisors in 50 children were randomly selected to be treated by FS pulpotomy (64) or RCT (69). RESULTS: Two years after treatment, 77 incisors (41 FS pulpotomy, 36 RCT) were available for clinical and radiographic examination. There was no clinical evidence of pathosis in 78% of FS pulpotomy-treated and 100% of RCT-treated incisors. Two independent pediatric dentists evaluated periapical radiographs of the treated incisors. Incisors were classified into 1 of 4 treatment outcomes: N, normal treated incisor; H, nonpathologic radiographic change present; PO, pathologic change present, but not requiring immediate extraction; PX, pathologic change present, extract immediately. Survival analysis was applied. A moderate level of agreement between raters was found for incisors with outcome PX (K = 0.54). Intra-rater reliability was substantial for incisors with outcome PX (K = 0.61). No difference was demonstrated in the proportion of FS pulpotomy- and RCT-treated incisors rated PX at the 2-year recall (x2 = 0.6). RCT incisors demonstrated a significantly higher survival rate than FS pulpotomy incisors at 2 years (p = 0.04). CONCLUSIONS: Treatment outcomes for RCT incisors were not significantly different from FS pulpotomy-treated incisors at 2 years; however, at 2 years the survival rate of RCT incisors was statistically greater than that of FS pulpotomy-treated incisors. (+info)
Evaluation of the permeability of the furcation area of deciduous molars conditioned with Er:YAG laser and cyanoacrylate.
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The purpose of this study was to evaluate in vitro the dentin permeability of the deciduous pulp chamber floor after employing 2-octyl cyanoacrylate and Er:YAG laser. Twenty four deciduous molars were used, divided into four groups. After chemical-surgical preparation each group received a different treatment: Group 1 - control, without treatment; Group 2 - the floor of the pulp chamber was covered with a fine layer of 2-octyl cyanoacrylate; Group 3 - the floor of the pulp chamber was irradiated with Er:YAG laser (250 mJ, 10 Hz for 30 seconds, 80 J of energy and 320 pulses), and covered with a fine layer of 2-octyl cyanoacrylate; and Group 4 - the floor of the pulp chamber was irradiated with Er:YAG laser set at the parameters already described. After that the specimens received application of 0.5% methylene blue, for 15 minutes. The teeth were cut, photographed, and the digitalized images were analyzed using the ImageLab program. The results obtained were submitted to statistical analysis. Group 4 (Er:YAG) presented the largest averages in percentage of dye penetration area (19.5%), followed by Group 1 (11.1%), Group 3 (1.4%) and Group 2 (0.2%). The experimental model allowed to conclude that the specimens conditioned with 2-octyl cyanoacrylate (Group 2) and Er:YAG laser associated to 2-octyl cyanoacrylate (Group 3) presented a decrease in permeability, and the specimens treated with Er:YAG laser (Group 4) presented an increase in permeability of the analyzed area. (+info)
Dentine phosphoproteins in gingival crevicular fluid during root resorption.
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External apical root resorption is a common, yet unexplained, phenomenon associated with orthodontic treatment. Available methods of clinical evaluation are radiographic. Biochemical assays offer the advantage of being non-invasive, as well as being diagnostic and potentially prognostic. The hypotheses are firstly that during the process of root resorption, organic matrix proteins are released into the gingival crevicular fluid (GCF) and, secondly, that there is a difference in the levels of these proteins between a group of patients with mild root resorption and a control group. GCF was collected from the permanent central incisors of untreated subjects (controls, n = 20), primary second molars with half of the root resorbed (primary group and positive controls, n = 20) and permanent central incisors with mild root resorption in patients undergoing active orthodontic treatment (orthodontic group, n = 20). Dentine phosphoproteins (DPP) were measured in the GCF using an enzyme-linked immunosorbent assay developed with DPP isolated from human first premolars and an antibody against rat incisor DPP. The primary group showed the highest levels of DPP in the GCF compared with the orthodontic (P = 0.296) and control (P = 0.001) groups. The orthodontic group showed elevated levels relative to the control group (P = 0.046). It is concluded that root resorption can be studied using a biochemical immunoassay and that this method can provide quantitative measurement of DPP in GCF. (+info)
Effects of a non-rinse conditioner on the enamel of primary teeth.
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The aim of this in vitro study was to evaluate by scanning electron microscopy the morphological aspects of the enamel of primary teeth after etching with 36% phosphoric acid or a non-rinse conditioner. Ten naturally exfoliated anterior primary teeth were selected. The samples were subjected to prophylaxis with pumice paste and water using a low-speed hand piece. Etching was done on the buccal surface. Specimens were divided into 2 groups: G1 (n=10): etching with 36% phosphoric acid gel - Conditioner 36 (Dentsply) for 20 s, followed by water rinse for 15 s; G2 (n=10): etching with NRC - Non Rinse Conditioner (Dentsply) for 20 s, followed by air drying for 15 s. The samples were dehydrated, mounted on metal stubs, coated with gold and observed with Jeol JSM-6100 scanning electron microscope. Electron-micrographic analysis showed that both etching agents were effective for etching the enamel of primary teeth causing the formation of microporosities on the enamel surface, although the etching pattern was more effective with the use of 36% phosphoric acid gel. (+info)