Centralization of services: standard setting and outcomes.

OBJECTIVE: To test specific standards set in the newly established cleft lip and palate service in three regions of the U.K. The standards relate to record collection and outcomes. DESIGN: Retrospective analysis. PATIENTS: Records of 31 children, 5 years of age, who were born in 1997 with complete unilateral clefts of lip and palate and were treated by surgeons in three regions. MAIN OUTCOME MEASURES: Record collection standards were measured by collecting dental study models. Outcomes were measured with the 5-Year-Old Index. RESULTS: Of the 31 subjects, 52% had excellent and good outcomes. The 31 cases represented 62% of the total records collected. CONCLUSIONS: The three regions examined fell short of the standards set, but the outcomes were improved compared with previous national outcomes. The failings in record collection need to be rectified. This study provides baseline data for further development of cleft services within three regions.

Functional appliances: mode of action and clinical use.

Functional appliances are frequently used in the treatment of class II division 1 malocclusions, either in isolation or, more commonly, before a course of fixed appliance therapy. Extensive speculation and investigation into the precise mode of action of these appliances has recently focused on their growth-restraining effect on the maxilla, their growth-enhancing effect on the mandible and dentoalveolar and soft-tissue effects. The different types of functional appliances are described in this article, with emphasis placed on practitioners adopting a component approach to design. A checklist is provided to aid identification of the more common problems occurring during treatment.

Long-term effect of neonatal endotracheal intubation on palatal form and symmetry in 8-11-year-old children.

Premature and low birth weight infants often require neonatal oral intubation for resuscitation and to relieve respiratory distress. The endotracheal tube exerts pressure on the developing palate, which can result in palatal groove formation, a high-arched palate, and palatal asymmetry. The purpose of this investigation was to determine whether such intubation can have a long-term effect on palatal form and symmetry. Arch widths, palatal widths, and palatal depths were measured from the study casts of 43, 8-11-year-old previously intubated premature and low birth weight children using a reflex microscope, with a fixed rectangular Cartesian co-ordinate system, and compared with a group of non-intubated gender- and age-matched controls. Significant differences were found between the intubated and non-intubated children. The intubated children had significantly narrower palatal widths posteriorly (P < or = 0.001), steeper palatal vaults anteriorly (P < or = 0.01), and exhibited a directional palatal width asymmetry with the left side of the palate measuring consistently wider than the right. These differences did not, however, appear to be affected by the length of intubation. Therefore, it is concluded that an oral endotracheal tube might exert excess force on the developing alveolus anteriorly with the tube being displaced to the right of the palate posteriorly leading to a steep anterior palatal vault and a left-sided palatal asymmetry, which can persist until the age of 11 years of age.

Functional appliances: mode of action and clinical use.

Functional appliances are frequently used in the treatment of Class II division 1 malocclusions, either in isolation or, more commonly, before a course of fixed appliance therapy. Extensive speculation and investigation into the precise mode of action of these appliances has recently focused on their growth-restraining effect on the maxilla, their growth-enhancing effect on the mandible and dentoalveolar and soft tissue effects. The different types of functional appliances are described in this article, with emphasis placed on practitioners adopting a component approach to design. A checklist is provided to aid identification of the more common problems occurring during treatment.

Preliminary study of articulatory reorganisation of fricative consonants following osteotomy.

Patients who undergo osteotomy experience a radical change in the skeletal relationship between the mandible and maxilla and as yet little is known about how this affects speech articulation. This study investigated the extent to which articulatory placement for the lingual consonant /s/ changed following surgery. Using the technique of electropalatography and acoustic analysis, patients' productions of fricative sounds were recorded before and after osteotomy. Five patients were investigated, 3 with mandibular prognathism and 2 with maxillary protrusion. Results showed that there were significant changes in articulatory placement after the operation, and that these were correlated with an acoustic measure (CPF). The direction of change could be predicted on the basis of the type of operation undergone, and these changes were maintained 6 months post-operatively. The implications of the findings are discussed.

Cannabinoids in humans. II. The influence of three methods of hydrolysis on the concentration of THC and two metabolites in urine.

Glucuronide conjugates of cannabinoids were previously identified in humans. For gas chromatographic-mass spectrometric (GC-MS) analysis of the unconjugated compounds in human urine, it is necessary to cleave the glucuronide moiety. Base hydrolysis and two forms of enzymatic hydrolysis were compared in this study to examine any quantitative differences between the hydrolysis methods. Human volunteers (n = 8) each smoked one marijuana cigarette containing 3.58% delta 9-tetrahydrocannabinol (THC) and submitted urine samples prior to smoking, 5 min after smoking, and hourly for 8 h thereafter. Urine (1 mL) was buffered to the optimum pH for each form of enzyme tested. beta-Glucuronidase from Escherichia coli (bacteria) or Helix pomatia (mollusk) was added to the specimens, followed by overnight incubation at 37 degrees C. Following hydrolysis, the samples were extracted using hexane-ethyl acetate (7:1) and derivatized with N,O-bis(trimethylsilyl)-trifluoroacetamide plus 1% trimethylchlorosilane, which converted the cannabinoids to their trimethylsilyl derivatives. GC-MS analysis revealed striking differences between the hydrolysis methods. Concentrations of unconjugated THC and 11-hydroxy-THC (11-OH-THC) using E. coli were significantly increased over all other methods tested (p < .05). These results demonstrate the species-dependent nature of glucuronidase activity in hydrolyzing THC and 11-OH-THC glucuronides and the ineffectiveness of base hydrolysis on these hydroxylated compounds. The need for further study to find the optimum conditions necessary for the complete hydrolysis of cannabinoid conjugates is suggested.

Auditory and visual P300 event related potentials are not altered in medically and psychiatrically normal chronic marihuana users.

Attempts to use Event Related Potentials, particularly the cognitive or P300 evoked potential, as measures of CNS effects of THC use have been infrequent and have produced inconsistent results. We published a pilot study in which psychiatric patient THC users had significantly prolonged auditory P300 latencies and reduced amplitudes as contrasted with non-users. Because psychiatric diagnoses and medication effects could not be controlled, we repeated the study with medically and psychiatrically normal subjects selected with extremely stringent exclusion criteria and screening procedures. P300 latency differences between THC users and controls were not detected. Using all subjects, THC users displayed reduced auditory and visual P300 amplitudes. However, when age differences between THC users and controls were removed, all significant P300 amplitude differences were removed as well. The contaminating effect of using psychiatric patients in THC research is discussed and the importance of using carefully screened normal subjects in studies of neurophysiological abuse drug effects is stressed.

Failed eruption of the permanent canine following open reduction of a mandibular fracture in a child.

A 10-year-old patient with failed eruption of the right mandibular canine associated with a retained metal plate previously placed to reduce a mandibular body fracture is presented. The incidence and site of mandibular fractures related to the developing permanent dentition and the relevance of this to popular methods of fixation employed in the reduction of fractures is discussed.