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This case report highlights the usefulness of bacterial culture and sensitivity testing in the prescribing of antibiotics for dental infections, demonstrated by the management of a 10-year-old child with a non-vital upper central incisor and, reportedly, associated recurrent tonsillitis.

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Two case reports are presented, both clearly demonstrating the diagnosis of oral-facial-digital syndrome, type I, but widely different in the expression of the condition. The first patient showed only mild expression of the syndrome. On examination at the age of 4 years there were no obvious extra oral signs, intraoral findings included the presence of supernumeraries in the primary dentition, spacing in two areas and the presence of an extra frenum. The second can be considered as a more severe case. This patient had many of the typical manifestations, including frontal bossing, a degree of zygomatic hypoplasia and clinodactyly. Orally, the most striking finding was a bilateral cleft palate which had not been diagnosed prior to examination at the age of 6 years. Other findings included multiple frena and a bifid tongue.

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X-linked amelogenesis imperfectas (AI) resulting from mutations in the amelogenin gene (AMELX) are phenotypically and genetically diverse. Amelogenin is the predominant matrix protein in developing enamel and is essential for normal enamel formation. To date, 12 allelic AMELX mutations have been described that purportedly result in markedly different expressed amelogenin protein products. We hypothesize that these AMELX gene mutations result in unique and functionally altered amelogenin proteins that are associated with distinct amelogenesis imperfecta phenotypes. The AMELX mutations and associated phenotypes fall generally into three categories. (1) Mutations (e.g., signal peptide mutations) causing a total of loss of amelogenin protein are associated with a primarily hypoplastic phenotype (though mineralization defects also can occur). (2) Missense mutations affecting the N-terminal region, especially those causing changes in the putative lectin-binding domain and TRAP (tyrosine rich amelogenin protein) region of the amelogenin molecule, result in a predominantly hypomineralization/hypomaturation AI phenotype with enamel that is discolored and has retained amelogenin. (3) Mutations causing loss of the amelogenin C terminus result in a phenotype characterized by hypoplasia. The consistent association of similar hypoplastic or hypomineralization/hypomaturation AI phenotypes with specific AMELX mutations may help identify distinct functional domains of the amelogenin molecule. The phenotype-genotype correlations in this study suggest there are important functional domains of the amelogenin molecule that are critical for the development of normal enamel structure, composition, and thickness.

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This paper describes a female with X-linked amelogenesis imperfecta (XAI). This case is unusual in having taurodontism, pulpal calcifications, coronal defects prior to tooth eruption and unerupted teeth. These findings have been reported in some cases of autosomal dominant and autosomal recessive AI but have not previously been documented in XAI.

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Dental genetic disorders can cause severe social and psychological effects in affected individuals. The cost of treatment can be considerable, not only in financial terms but also in time spent during treatment. In theory it is, or will soon be, possible to use advances in molecular genetics for pre-natal testing, for selection of embryos using in vitro fertilization techniques, and for gene therapy. The questions we pose are whether these approaches are appropriate. We hope that this review will stimulate debate on these issues.

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Amelogenesis imperfecta (AI) is a collective term for a number of conditions with abnormal enamel formation. Many cases are inherited, either as an X-linked, autosomal dominant or autosomal recessive trait. Several classifications have evolved since 1945, based primarily on phenotype with the mode of inheritance being used in some systems as a secondary factor in allocating a case into a particular category. The benefits and shortcomings of these systems are reviewed. As we move into an era of establishing the molecular basis of AI we propose a robust mechanism for classification and cataloguing of the disorder which parallels systems used in medical genetics. This system is applicable to individuals and families irrespective of current or future knowledge of the molecular defect involved. We argue that this system is of more benefit to these individuals and families than previous classifications.

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This report describes the case of an 8-year-old girl with focal dermal hypoplasia. As well as deformities affecting her hands and feet she had marked facial asymmetry, one diminutive eye and coloboma affecting the other. Intraorally, the patient had papillomas at the base of the tongue and tonsils. Her teeth showed irregular spacing, hypodontia, enamel hypoplasia, anomalous tooth form and delayed development. Radiographically, several teeth showed abnormal form. The patient's previous surgical experiences had adversely affected her behaviour and treatment has been limited to patient motivation and oral hygiene instructions, acclimatization, and simple restorative care.

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This paper describes the case of a day old baby who was admitted to hospital because of the presence of a large intraoral swelling that was preventing her from breast feeding. Clinical examination showed a firm, pedunculated, lobulated nodule protruding from the mouth and attached to the maxillary alveolus to the left of the midline. The mucosa was normal in appearance. The growth was excised under local anaesthesia and showed a histological appearance consistent with a congenital epulis of the newborn. Healing was complete and no recurrence was seen at review after two weeks. Conservative treatment of congenital epulis is often sufficient but in this case, the nodule prevented feeding. Excision was incomplete but, as in other cases treated in the same way, there has been no obvious tendency to recur.

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OBJECTIVE: To use molecular genetics to establish the mode of inheritance in a family with amelogenesis imperfecta. MATERIALS AND METHODS: The polymerase chain reaction was used to amplify exons of the amelogenin gene on the short arm of the X chromosome. RESULTS: A single base deletion mutation in exon 6 of the amelogenin gene was identified. This mutation was a single base deletion of a cytosine residue - 431delC - in codon 96 of exon 6, introducing a stop codon 30 codons downstream of the mutation in codon 126 of the exon. CONCLUSION: The firm establishment of an X-linked mode of inheritance affects the genetic counselling for this family.

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The objective of this study was to review published reports on the epidemiology of primary brain tumours in adults and present the body of knowledge related to these tumours in Great Britain and Ireland. A literature search of all published epidemiological data on brain tumours was conducted in Pre-Medline, Medline, Embase and the Cochrane databases from 1966 to the present. A hand search of all the references alluded to was conducted and older studies identified. The articles were reviewed and tabulated. The papers were subjected to descriptive analysis. Information available to the public and held with the Cancer Registries was reviewed, and cross-referenced with published evidence. To our knowledge, only seven papers have discussed the epidemiology of primary brain tumours in adults. The different methodology of the population-based studies of brain tumours and the different time periods they investigated makes them incomparable. Two papers with comprehensive and detailed strategies for case ascertainment have both recorded tumour incidences of 21 per 100,000 person years. The results of the better studies are at variance with reports from the Cancer Registries. On the basis of the current studies, Cancer Registries appear to under-estimate the incidence of such tumours in adults. It is apparent that a significant number of tumours especially benign varieties are not recorded by some Cancer Registries. The previous estimates, patterns of incidence, prevalence, and survival of brain tumours in Great Britain and Ireland, may thus be incorrect. Patterns of primary brain tumours in adults have not been widely reported in GB and Ireland and the aetiology remains largely unknown. The need for current estimation of geographical and secular variations was identified. This demands closer co-operation between medical and allied staff, and the Cancer Registries. Prospective regional studies of incidence patterns and up to date epidemiological appraisal is deemed necessary. Meanwhile, Cancer Registries should seriously consider the inclusion of all primary brain tumours in their database.

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Amelogenin, the predominant matrix protein in developing dental enamel, is considered essential for normal enamel formation, but its exact functions are undefined. Mutations in the AMELX gene that encodes for amelogenin protein cause X-linked amelogenesis imperfecta (AI), with phenotypes characterized by hypoplastic and/or poorly mineralized enamel. Eight different AMELX deletion and substitution mutations have been reported to date. The purpose here was to evaluate the genotype and phenotype of two large kindreds segregating for X-linked AI. Phenotypically affected males in family 1 had yellowish-brown, poorly mineralized enamel; those in family 2 had thin, smooth, hypoplastic enamel. Heterozygous females in both kindreds had vertical hypoplastic grooves in their enamel. DNA was obtained from family members; exons 1-7 of AMELX were amplified and sequenced. Mutational analysis of family 1 revealed a single-base-pair change of A-->T at nucleotide 256, resulting in a His-->Leu change. Analysis of family 2 revealed deletion of a C-nucleotide in codon 119 causing a frameshift alteration of the next six codons, and a premature stop codon resulting in truncation of the protein 18 amino acids shorter than the wild-type. To date, all mutations that alter the C-terminus of amelogenin after the 157th amino acid have resulted in a hypoplastic phenotype. In contrast, other AMELX mutations appear to cause predominantly mineralization defects (e.g. the mutation seen in family 1). This difference suggests that the C-terminus of the normal amelogenin protein is important for controlling enamel thickness.

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This paper describes the clinical features of a family of four generations with autosomal dominant amelogenesis imperfecta with taurodontism (ADAIT). Considerable variation in phenotype was seen, both between individuals and within the dentition of some individuals. Many of the adults had received extensive dental restorative work. These findings re-enforce previous observations of variable phenotype in this and other forms of the condition and add to the argument for a revision of methods of classification. This history of this large family draws further attention to the restorative demands of this group of dental anomalies and, by their generous co-operation, will prove an invaluable help in the investigation by molecular genetic techniques of this disfiguring condition.

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Local anaesthesia is used routinely in dental surgery; it is effective in both pain control and--through the vasoconstrictors often contained within it--the reduction of bleeding. The extraction of deciduous teeth under general anaesthesia is often carried out without these local effects. There are no previous studies to investigate the combined effect of local anaesthesia with general anaesthesia on blood loss and pain control. A randomised, controlled clinical trial was carried out with one hundred children aged 3-5 years. Ethical approval and informed consent were obtained. Surface anaesthetic cream (EMLA) was placed on the hand into which the intravenous access was to be placed. One to two ml of blood was taken at the time of induction as a baseline of the patient's level of haematin pigment. Children in the experimental group were given one quarter of a cartridge (0.5 ml) of local anaesthetic containing epinephrine (1:80,000) in each quadrant before tooth extraction; all blood in swabs, suction equipment and disposables was collected and digested with NaOH. The children were observed for 11 minutes post-operatively for any signs of distress. Total blood loss was calculated by comparison of the baseline sample and the shed blood digests. This study showed that using local anaesthesia for dental extractions under general anaesthesia was associated with decreased blood loss (p = 0.001). The second finding--which has not been reported before--was that this use of local anaesthesia was shown to cause distress to this age group of children upon recovery from the general anaesthetic (p <0.0001). The use of local anaesthetic in this situation provided a useful reduction in post-operative bleeding. However, its use was associated with greater post-operative distress.

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This study compared the treatment provided for patients with supernumerary teeth in Bristol Dental Hospital with those in Westmead Dental Hospital, Sydney, Australia. The records of 63 children referred for removal of a supernumerary tooth in Bristol and 96 children in Westmead were examined, involving a total of 215 supernumerary teeth. Differences in the treatment provided for these patients were found not only between the two centres but also within one centre. There appeared to be no standardised route by which these patients were seen and therefore no standardised pattern of treatment. Contact with all UK Dental Schools indicated that no formal treatment protocol existed for the treatment of children with supernumerary teeth. In addition, a permanent incisor associated with a conical supernumerary tooth was twice as likely to erupt spontaneously as one associated with a supernumerary of tuberculate form. The location of the supernumerary tooth also influenced the likelihood of spontaneous eruption of the associated permanent incisor. There is a need for a prospective randomised controlled trial in the future in order to develop a formal treatment protocol for the management of patients with supernumerary teeth. A multicentre trial is under development.

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While specifying "responsibilities" for river planning and management implies that outcomes are desired, defining "accountabilities" demands that results are achieved. This paper examines innovative ways of converting aspirations to results, with particular reference to the changes initiated in New South Wales in response to the establishment of the Healthy Rivers Commission of New South Wales and its first round of inquiries.

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A case is presented of a child with remarkably trifid (vertically divided into three) permanent central incisor teeth and multiple systemic findings that do not appear to correspond to any previous diagnosis. Systems affected include skin, musculoskeletal, urinogenital and orofacial. The child is of normal intelligence and good general health.

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This is the second of two articles looking at dental care for the patient with a cleft lip and palate. Part 1 looked at the needs of the child from birth through to the mixed dentition stage. Part 2 looks at dental care from the mixed dentition stage through to adolescence and young adulthood.

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This is the first of two articles looking at dental care for the patient with a cleft lip and palate. Part 1 looks at the needs of the child with a cleft lip and palate from birth through to the mixed dentition stage.

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