Biomedical subjects

B Bäckman

Publications and source records attributed to B Bäckman.

At least 19 recordsLinked to original sources

PubMed2005

Teaching oral hygiene to children with autism.

BACKGROUND: The need for improved oral hygiene routines in individuals with disabilities has been documented in many reports. The aim of this study was to evaluate whether visual pedagogy is a suitable way to teach children with autism how to brush their teeth. METHODS: The investigation took the form of a prospective study including clinical examinations and structured interviews. Based on visual pedagogy, a series of pictures were produced that showed a structured method and technique of tooth brushing. The pictures were placed in the bathroom or wherever tooth brushing was performed. Fourteen children with autism aged between 5 and 13 years (mean age = 9.3 years), and their parents participated. RESULTS: Before the study, all parents found it difficult/very difficult to maintain good oral hygiene in their child. All children had visible plaque on their maxillary incisors and canines. After 12 months, the amount of visible plaque was reduced. After 18 months, most parents found maintaining good oral hygiene easier than before the study. All but one child/parent adopted the programme. CONCLUSIONS: Visual pedagogy is a useful tool in helping people with autism to improve their oral hygiene.

Adolescent↗

PubMed2003

Children with Down Syndrome: oral development and morphology after use of palatal plates between 6 and 18 months of age.

OBJECTIVES: The aim of this study was to describe oral development and morphology in 18-month-old children with Down syndrome (DS) treated with palatal plates in combination with structured communication and speech training. The aim is further to describe the design of the palatal plates, compliance in their use and to give a brief report of their effect on oral motor function and speech. SAMPLE AND METHODS: Forty-two children with DS were followed from < or = 6 months of age until 18+/-3 months old. In addition to language intervention, and oral motor and sensory stimulation provided by speech therapists for all children with DS in Sweden, palatal plates provided by dentists are included in the training programme. In the evaluation, the children in the project were compared with two control groups of children matched for age; one group of children with DS who had not been treated with palatal plates, and one group of children with normal development. RESULTS: Compared to the children with normal development, both groups of children with DS had fewer teeth erupted and a lower prevalence of sucking habits. Deviant morphology of the tongue in the form of diastase, lingua plicata or a sulcus in the anterior third of the tongue was only seen in children with DS. All children with normal development had positive values for overjet compared to 53% of the children with DS. The palatal plates were used 2-3 times daily for a total mean time of 15 min. Compliance in use of the plates decreased with age, mainly due to eruption of teeth and subsequent loss of retention. Evaluation of oral motor function and speech show that the children with DS in the project had better motor prerequisites for articulation than the control children with DS. CONCLUSION: Palatal plate therapy did not affect oral parameters, i.e., eruption of teeth, types and prevalence of sucking habits, tongue morphology and symptoms of hypotonia. In combination with oral motor and sensory stimulation, palatal plate therapy had a positive effect on oral motor performance and prerequisites for articulation.

Case-Control Studies↗

PubMed2002

Inheritance pattern and elemental composition of enamel affected by hypomaturation amelogenesis imperfecta.

Hypomaturation amelogenesis imperfecta (AI) is characterized clinically by enamel of normal thickness that is hypomineralized, mottled, and detaches easily from the underlying dentin. Autosomal dominant, autosomal recessive, X-linked, and sporadic modes of inheritance have been documented. The present study investigated the elemental composition of the enamel of teeth from individuals demonstrating clinical hypomaturation AI from families representing three of these patterns of inheritance. The aim of the study was to determine if there was any commonality in microscopic phenotype of this defect between families demonstrating the various inheritance patterns. One section from each tooth was microradiographed and then viewed in a scanning electron microscope (SEM) equipped with an ultrathin window energy-dispersive x-ray spectroscopy (EDX) detector. In the SEM, prisms and constituent crystals in discrete areas appeared to be largely obscured by an amorphous material. EDX analysis showed enamel outside these areas to have a composition indistinguishable from control teeth. However, within these affected areas there was a large increase in carbon content (up to a fivefold increase). In some teeth there was also a detectable but smaller increase in the relative amounts of nitrogen or oxygen. The results suggest the defect in these teeth with a common clinical phenotype, irrespective of the pattern of inheritance, demonstrates a commonality in microscopic phenotype. The large increase in carbon content, not matched by an equivalent increase in nitrogen or oxygen, suggests a possible increased lipid content. In those teeth with elevated nitrogen levels there may also be retained protein.

Amelogenesis Imperfecta↗

PubMed2001

Human ameloblastin gene: genomic organization and mutation analysis in amelogenesis imperfecta patients.

A gene encoding the enamel protein ameloblastin (AMBN) was recently localized to a region on chromosome 4q21 containing a gene for the inherited enamel defect local hypoplastic amelogenesis imperfecta (AIH2). Ameloblastin protein is located at the Tomes processes of secretory ameloblasts and in the sheath space between rod-interrod enamel, and the AMBN gene therefore represents a viable candidate gene for local hypoplastic amelogenesis imperfecta (AI). In this study, the genomic organization of human AMBN was characterized. The gene was shown to consist of 13 exons and 12 introns. An alternatively spliced 45 bp sequence was shown not to represent a separate exon and is most likely spliced by the use of a cryptic splice site. The finding that there were no recombinations between an intragenic microsatellite and AIH2 encouraged us to evaluate this gene's potential role as a candidate gene for local hypoplastic AI. Mutation screening was performed on all 13 exons in 20 families and 8 sporadic cases with 6 different forms of AI. DNA variants were found but none that was associated exclusively with local hypoplastic AI or any of the other variants of AI in the identified Swedish families. This study excludes the coding regions and the splice sites of AMBN from a causative role in the pathogenesis of AIH2.

Amelogenesis Imperfecta↗

PubMed2001

Variations in number and morphology of permanent teeth in 7-year-old Swedish children.

OBJECTIVES: To establish the prevalence of numerical and morphological variations of permanent teeth in Swedish 7-year-olds and to accept or reject the hypothesis of a higher prevalence for these conditions in northern Sweden compared to other areas. DESIGN: Cross-sectional. SETTING: Department of Odontology/Pedodontics, Umeå University, Sweden. SAMPLE AND METHODS: A total of 739 healthy Caucasian 7-year-olds residing in the city of Umeå, northern Sweden in 1976. The children were examined clinically and radiographically. RESULTS: The prevalence of hypodontia (excluding third molars) in girls was 8.4%, in boys 6.5%, and in both sexes combined 7.4%. Of the children with hypodontia, the majority (90.9%) lacked one or two teeth. Lower second premolars were the teeth most frequently missing. The prevalence of hyperdontia was 1.9%; 11 girls and three boys were affected; 78% of the supernumerary teeth were mesiodenses. Of the morphological variations, peg-shaped upper lateral incisors were found in 0.8% of the children, double-formation (gemination) in 0.3%, taurodontism in 0.3% and dens invaginatus in 6.8%. One diagnosis was found in 18% of the children, and in almost 8% of them more than one diagnosis was found. CONCLUSIONS: The results agree with those obtained in similar populations and are considered representative of this ethnic group. The hypothesis of a genetically determined higher prevalence of numerical and morphological variations in the study population was not verified.

Anodontia↗

PubMed2001

Conscious sedation by oral administration of midazolam in paediatric dental treatment.

Midazolam is a short-acting benzodiazepine with rapid onset, short duration of action and minimal side effects. The aim of this study was to evaluate the oral administration of midazolam as pre-operative sedation in the dental treatment of uncooperative pediatric patients. Included in the study were 160 children with a mean age of 6.7 +/- 2.6 years (1-14 years), 83 boys and 77 girls. All the patients had been referred for specialist treatment due to behavioral management problems. Treatment was performed in 250 sessions. All the children received an oral dose of 0.2 mg/kg body weight of midazolam. Acceptance of treatment was evaluated according to Rud & Kisling. Local anesthesia followed by restorative treatment and/or extractions constituted more than 90% of the performed treatments. Of the 250 sessions, 63% were performed with total acceptance and 30% with doubtful acceptance. In 7%, no treatment could be performed. No serious complications were registered during or after treatment. All the children were able to leave the clinic one hour after treatment. In conclusion, we consider oral administration of midazolam a safe form of premedication. The route of administration, the short waiting-time and half-life, in combination with a level of sedation that allows treatment to be performed, are the principal advantages of conscious sedation with orally administered midazolam.

Administration, Oral↗

PubMed1997

Mapping of the locus for autosomal dominant amelogenesis imperfecta (AIH2) to a 4-Mb YAC contig on chromosome 4q11-q21.

Amelogenesis imperfecta (AI) is a clinically and genetically heterogeneous group of inherited enamel defects. We recently mapped a locus for autosomal dominant local hypoplastic amelogenesis imperfecta (AIH2) to the long arm of chromosome 4. The disease gene was localized to a 17.6-cM region between the markers D4S392 and D4S395. The albumin gene (ALB), located in the same interval, was a candidate gene for autosomal dominant AI (ADAI) since albumin has a potential role in enamel maturation. Here we describe refined mapping of the AIH2 locus and the construction of marker maps by radiation hybrid mapping and yeast artificial chromosome (YAC)-based sequence tagged site-content mapping. A radiation hybrid map consisting of 11 microsatellite markers in the 5-cM interval between D4S409 and D4S1558 was constructed. Recombinant haplotypes in six Swedish ADAI families suggest that the disease gene is located in the interval between D4S2421 and ALB. ALB is therefore not likely to be the disease-causing gene. Affected members in all six families share the same allele haplotypes, indicating a common ancestral mutation in all families. The AIH2 critical region is less than 4 cM and spans a physical distance of approximately 4 Mb as judged from radiation hybrid maps. A YAC contig over the AIH2 critical region including several potential candidate genes was constructed.

Albumins↗

PubMed1997

Inherited enamel defects.

This paper describes the clinical, histological and genetic findings in individuals with amelogenesis imperfecta diagnosed in more than 50 families in the county of Västerbotten, northern Sweden. Using pedigree analysis, families with autosomal and X-linked inheritance as well as sporadic cases of amelogenesis imperfecta have been recognized. A clinical subclassification in eight different variants of amelogenesis imperfecta has been made. The gene defects have been identified for two of these variants and the chromosomal location has been established for a third variant.

Amelogenesis Imperfecta↗

PubMed1995

Amelogenin signal peptide mutation: correlation between mutations in the amelogenin gene (AMGX) and manifestations of X-linked amelogenesis imperfecta.

Formation of tooth enamel is a poorly understood biological process. In this study we describe a 9-bp deletion in exon 2 of the amelogenin gene (AMGX) causing X-linked hypoplastic amelogenesis imperfecta, a disease characterized by defective enamel. The mutation results in the loss of 3 amino acids and exchange of 1 in the signal peptide of the amelogenin protein. This deletion in the signal peptide probably interferes with translocation of the amelogenin protein during synthesis, resulting in the thin enamel observed in affected members of the family. We compare this mutation to a previously reported mutation in the amelogenin gene that causes a different disease phenotype. The study illustrates that molecular analysis can help explain the various manifestations of a tooth disorder and thereby provide insights into the mechanisms of tooth enamel formation.

Amelogenesis Imperfecta↗

PubMed1994

Craniofacial structure related to inheritance pattern in amelogenesis imperfecta.

The aim of this study was to investigate the craniofacial structure in 66 children and adolescents, 34 girls and 32 boys, with known clinical manifestations and inheritance patterns for amelogenesis imperfecta (AI), and to compare the results with those obtained in a control group of age and sex matched persons with normal occlusion. The ages ranged from 6.8 to 21.2 years. Clinically, AI was divided into cases characterized by either hypoplasia or hypomineralization of the enamel. In a further subgrouping, eight clinical variants were diagnosed. Measurements of 12 angular and 15 linear, parameters on lateral cephalometric radiographs were included in comparisons between the AI and the control group. Compared with the control group, the AI group displayed statistically significant differences indicating a skeletal open bite. In the analysis of inheritance patterns and clinical manifestations, a skeletal open bite was associated with autosomal dominant (AD) and X-linked inheritance, and in the AD group with hypomineralization. When all cases except those with X-linked inheritance were pooled, deviations indicating a skeletal open bite were found in the subgroups "rough hypoplastic AI" and "hypomineralization AI." Since a skeletal open bite was found both with X-linked inheritance and in some of the subgroups connected with autosomal inheritance, the hypothesis of a pleiotropic gene effect as the cause of the simultaneous occurrence can be ruled out. The influence of modifying genes or environmental factors is suggested.

Adolescent↗

PubMed1994

Localization of a gene for autosomal dominant amelogenesis imperfecta (ADAI) to chromosome 4q.

Amelogenesis imperfecta (AI), is an inherited odontological disease which affects the formation of enamel. We report a linkage analysis study performed on three Swedish families, where the affected members had an autosomal dominant variant of AI (ADAI) clinically characterized as local hypoplastic. Significant linkage to microsatellite markers on chromosome 4q were obtained. Recombinations localized the ADAI locus to a chromosome region which contains both a locus for the dental disorder dentinogenesis imperfecta and the albumin gene. Serum albumin has been suggested to play a role in enamel formation, and the albumin gene is therefore a candidate gene for this genetic disease.

Amelogenesis Imperfecta↗

PubMed1994

Mineral distribution in the enamel of teeth with amelogenesis imperfecta as determined by quantitative microradiography.

The aim of the present investigation was to determine the mineral distribution in the enamel of teeth with amelogenesis imperfecta (AI) by quantitative microradiography. A further aim was to correlate the findings to clinical manifestations and inheritance patterns for AI. Included in the study were a total of 29 teeth with AI, 28 primary and one permanent, and seven unaffected teeth, five primary and two permanent. Quantitative microradiography was applied to sagittally ground sections, 70-90 microns, of the teeth. The mineral content of the enamel, expressed as percentage by volume, was lower in most of the teeth with AI than in the unaffected teeth. The largest range for the mineral distribution was found in the enamel of the variants clinically characterized by hypomineralization. These teeth showed a mineral distribution pattern that reflected an extremely low mineral content in the bulk of the enamel. In the AI teeth clinically characterized by hypoplasia, the mineral distribution pattern was similar to that of the unaffected teeth, although with larger local variations in mineral content. Apart from the teeth connected with X-linked inheritance, no differences were found among teeth with similar clinical variants connected with different inheritance patterns.

Amelogenesis Imperfecta↗

PubMed1993

The absence of correlations between a clinical classification and ultrastructural findings in amelogenesis imperfecta.

This study was performed to examine whether a clinical classification of different phenotypes of amelogenesis imperfecta could be discernible at the ultrastructural level. Seventeen primary teeth from 16 children with hypomineralization, hypomaturation, or hypoplastic variants of the disease were collected for histologic studies of the enamel by means of polarized light microscopy, scanning electron microscopy (SEM), and secondary ion mass spectrometry (SIMS). Polarization microscopy showed that the enamel was hypomineralized; in six teeth a wavy configuration of the enamel prisms also appeared. Three histomorphologic main types could be discerned. In 10 of the teeth extensive hypomineralization of the bulk of the enamel was found. One tooth had an unusually thick enamel with only a thin normally mineralized surface layer. SIMS images showed less pronounced signals from Ca2+ and Na+ but with stronger signals from Cl- and CN-, representing the organic component of enamel. The SEM images showed an irregular prism pattern with marked interprismatic areas. Irrespective of the clinical appearance or the hereditary pattern the main findings were hypomineralized enamel with or without wavy bands. Neither of the analytical methods used in this paper distinguishes between the clinical phenotypes of amelogenesis imperfecta.

Amelogenesis Imperfecta↗

PubMed1991

A deletion in the amelogenin gene (AMG) causes X-linked amelogenesis imperfecta (AIH1).

Amelogenesis imperfecta is characterized by the defective formation of tooth enamel. Here we present evidence that the X-linked form of this disorder (AIH1) is caused by a structural alteration in one of the predominant proteins in enamel, amelogenin. Southern blot analysis revealed a deletion extending over 5 kb of the amelogenin gene in males with the hypomineralization form of the AIH1. Carrier females were heterozygous for the molecular defect. The deletion appears to include at least two exons of the amelogenin gene and the extent of the deletion was verified by PCR analysis. The mutation was shown to segregate with the disease among 15 analyzed individuals belonging to the same kindred. Our results link a defect in the amelogenin gene to the abnormal formation of enamel. We thus conclude that the amelogenin protein has a role in biomineralization of tooth enamel.

Amelogenesis Imperfecta↗

PubMed1990

Mapping of the gene for X-linked amelogenesis imperfecta by linkage analysis.

X-linked Amelogenesis imperfecta (AI) is a genetic disorder affecting the formation of enamel. In the present study two families, one with X-linked dominant and one with X-linked recessive AI, were studied by linkage analysis. Eleven cloned RFLP markers of known regional location were used. Evidence was obtained for linkage between the AI locus and the marker p782, defining the locus DXS85 at Xp22, by using two-point analysis. No recombination was scored between these two loci in 15 informative meioses, and a peak lod score (Zmax) of 4.45 was calculated at zero recombination fraction. Recombination was observed between the more distal locus DXS89 and AI, giving a peak lod score of 3.41 at a recombination fraction of .09. Recombination was also observed between the AI locus and the more proximal loci DXS43 and DXS41 (Zmax = 0.09 at theta max = 0.31 and Zmax = 0.61 at theta max = 0.28, respectively). Absence of linkage was observed between the AI locus and seven other loci, located proximal to DXS41 or on the long arm of the X chromosome. On the basis of two-point linkage analysis and analysis of crossover events, we propose the following order of loci at Xp22: DXS89-(AI, DXS85)-DXS43-DXS41-Xcen.

Amelogenesis Imperfecta↗

PubMed1989

Amelogenesis imperfecta: a scanning electron microscopic and microradiographic study.

The aim of the present study was to use scanning electron microscopy (SEM) to visualize the morphology of the enamel surface in 12 primary teeth from children with amelogenesis imperfecta (AI). The observations were correlated to genetic, clinical and microradiographic data from the same teeth and to non-affected control teeth. SEM showed similar disturbances in teeth with a clinical predominance of hypoplasias and in teeth with a predominance of hypomineralization. In the microradiographs the enamel of most teeth showed both hypoplasias and areas of hypomineralization, independently of the predominant clinical manifestation. In the one boy with an X-linked inheritance pattern, both SEM and microradiography showed the morphology of the enamel to be unique in the present study. In the other teeth, similar manifestations were found in cases with AI as an AD trait and in the sporadic cases.

Amelogenesis Imperfecta↗

PubMed1989

Microradiographic study of amelogenesis imperfecta.

A material of 22 primary and 4 permanent teeth from 22 children with amelogenesis imperfecta (AI) were examined by microradiographic techniques. The children were part of a patient material earlier examined in genetical and clinical studies. The results were compared with corresponding data two non-affected control groups and correlated with the available clinical and genetical data. Teeth were examined from seven of the eight different variants of AI seen in the clinical study. In most cases both hypoplasias and areas of hypomineralization were observed in the same tooth, indicating that both the secretory and the maturation phases of the amelogenesis are affected in AI. In teeth from children with the same clinical variant but different inheritance patterns, no specific finding could be related to a specific inheritance pattern. The findings in the one boy with AI as an X-linked trait were unique in this material. In all control teeth except one, no hypoplasisas or areas of hypomineralization were found in the enamel. In conclusion, the subclassification of AI into different forms can be questioned. Variations in clinical and histologic characteristics connected with the same inheritance pattern suggest that the genetic defect, in conjuction with a large biological variation, could explain the multiplicity in clinical expressivity that characterizes AI.

Amelogenesis Imperfecta↗

PubMed1988

Amelogenesis imperfecta--clinical manifestations in 51 families in a northern Swedish county.

The clinical manifestations of amelogenesis imperfecta (AI) were described in 165 individuals from 51 families. The inheritance pattern for AI in these families had previously been investigated, and it was hypothesized that AI probably is solely an autosomal dominant (AD) or X-linked trait. To test this hypothesis the connection between clinical manifestation and inheritance pattern was studied. Eight different variants of AI were seen. In 33/51 families all affected individuals could be assigned to the same clinical variant. In 8/51 families those affected were assigned to different clinical variants. In the two families where an X-linked recessive (XR) inheritance pattern was found probable, the clinical manifestation differed between women and men. Except for one variant only seen as an AD trait, and the manifestation in women in families with an X-linked recessive inheritance pattern, no connection was found between a specific inheritance pattern and a specific clinical manifestation. Accordingly it seems likely that AI is solely an AD or X-linked trait. The different clinical variants observed should be regarded as a varying expressivity of the gene and in the families with X-linked inheritance probably due to lyonization. In the remaining families the modifying mechanisms are not known.

Adolescent↗