PubMed Health⌕ Search

Biomedical subjects

C M Forsberg

Publications and source records attributed to C M Forsberg.

At least 37 records · Page 2Linked to original sources
PubMed1991

Face height and tooth eruption in adults--a 20-year follow-up investigation.

A longitudinal roentgen cephalometric investigation of vertical craniofacial and dentoalveolar changes during 20 years of adulthood, was performed in 15 men and 15 women. Two lateral cephalograms taken at the average ages 25 and 45 years, were available of each subject. Skeletal and dental changes were described by 13 linear and four angular cephalometric measurements. The analysis of the linear variables showed that total anterior face height increased by 1.60 mm on average. Approximately one-fifth of this increase occurred in the upper and four-fifths in the lower face. In the dentoalveolar region, significant increments of all dimensions except overjet and overbite were found, indicating an eruptive movement of the teeth and a vertical development of their investing tissues. The analysis of the angular measurements showed that posterior rotation of the mandible and uprighting of the upper incisors had occurred during the period of investigation.

Adult↗
PubMed1991

Ligature wires and elastomeric rings: two methods of ligation, and their association with microbial colonization of Streptococcus mutans and lactobacilli.

Twelve orthodontic patients undergoing treatment with fixed appliances took part in the present study. In all patients elastomeric rings were used for ligation on one side of the dental arch midline, whereas steel wires were used on the opposite side. The number of micro-organisms in samples of plaque, taken from the labial surface of the upper lateral incisors, was recorded on five occasions during treatment. In samples of saliva, the numbers of Streptococcus mutans and lactobacilli were recorded on the same occasions. This registration was also made on two occasions before insertion of the fixed appliance, and 6 weeks after the period of active treatment. The results showed that, in the majority of patients, the incisor which was attached to the arch-wire with an elastomeric ring, exhibited a greater number of micro-organisms in the plaque than the incisor ligated with steel wire. Following insertion of fixed appliances the number of S. mutans and lactobacilli in saliva increased significantly. Variations in the number of micro-organisms in the saliva during active treatment were not reflected in any relative increase or decrease in microbial colonization on either steel ligatures or elastomeric rings. The use of retainers after active treatment was not associated with increased numbers of micro-organisms in the saliva.

Adolescent↗
PubMed1991

Craniofacial growth in bone marrow transplant recipients treated with growth hormone after total body irradiation.

The effect of growth hormone (GH) treatment on craniofacial development was studied in five children exhibiting growth retardation following bone marrow transplantation. Linear and angular measurements were made on lateral radiographic cephalograms taken prior to the start of GH treatment and after an average treatment time of 1.2 yr. The results showed that the mean growth increments of mandibular length in the GH treated children, exceeded the corresponding values of the control group by 150% during the period of investigation. It is suggested that this dimensional increase in the patients was due to GH stimulation on the chondral growth process in the mandibular condyles.

Adolescent↗
PubMed1990

Traumatic injuries to teeth in Swedish children living in an urban area.

The prevalence of dental injuries in the permanent dentition was studied in a population comprising 1635 Swedish school children aged 7-15 years. A retrospective study of dental injuries in the deciduous dentition was also carried out. A total of 483 (30%) children in the material had experienced dental injuries. Twelve per cent of the injuries had been sustained before the age of 7 years and 18 per cent after that age. The majority of injuries had occurred between the ages 3-10 years. In the permanent dentition, over 75 per cent of the injuries recorded had been sustained before the age of 11 years. Boys had a higher trauma frequency than girls, the sex ratio being 1.2:1 in the deciduous dentition and 1.6:1 in the permanent dentition. Thirty per cent of the injured deciduous teeth required some kind of treatment. The corresponding figure for the permanent dentition was 46 per cent.

Adolescent↗
PubMed1989

Identification of the cephalometric reference point condylion on lateral head films.

The tracing error of the cephalometric reference point condylion was studied in two groups of children with the mean ages 11 and 13 years. Two lateral cephalograms of each subject were available. The first film had been taken according to the standard method with the teeth in habitual occlusion, and the other with the mouth open to maximum extent. The condylion was registered on all films on two occasions with an interval of one month. The distance condylion-prognathion (mandibular length) was also recorded. The tracing error was found to be significantly greater when the condylion was located on occlusion films as opposed to open mouth films. The greatest precision of an individual measurement of mandibular length was, therefore, achieved on open mouth films. For group means, however, there was no significant difference between occlusion and open mouth films.

Adolescent↗
PubMed1989

Facial growth and morphology in long-term survivors after bone marrow transplantation.

A roentgen cephalometric investigation was used to study facial growth and morphology in 17 children who had undergone bone marrow transplantation (BMT) because of acute leukaemia and aplastic anaemia. The ages at BMT varied from 1.0 to 12.9 years. Preoperative treatment included high doses of cyclophosphamide and in children with acute leukaemia also 10 Gy total body irradiation (TBI). The median observation period following BMT was 3.9 years. The control group comprised 85 age and sex matched healthy children. In comparison to the controls, all linear measurements studied were found to be significantly diminished in children conditioned with TBI. For variables describing vertical dimensions, the degree of reduction appeared to be associated with the patients' ages at the time of irradiation. It was concluded that the disturbance in dental development, which is also a consequence of TBI, could be partly responsible for this association. Children who were not conditioned with TBI exhibited no significant differences when compared to controls in respect of the variables studied.

Bone Marrow Transplantation↗
PubMed1989

Effect of chemotherapy on dental maturity in children with hematological malignancies.

Dental maturity or dental age was determined in 44 children with hematological malignancies treated with chemotherapy. No significant difference was observed between the chronological and dental age in children treated with chemotherapy compared to healthy controls. With regard to the number of erupted permanent teeth, no significant differences could be found between the two groups. The results indicate that chemotherapy given to children with hematological malignancies did not interfere with dental maturity or eruption of permanent teeth.

Adolescent↗
PubMed1989

Mandibular third molar eruption in relation to available space as assessed on lateral cephalograms.

It has previously been suggested that the distance between the Xi point (Ricketts 1972) and the distal aspect of the mandibular second molar (M2), measured on lateral cephalometric head films, should be at least 25 mm by adulthood to allow for the normal eruption of the third molars (M3s) in the lower jaw. It was the aim of this investigation to test the validity of this statement in two groups of young adults (mean age 25 years). The individuals in the first group had complete dentitions including M3s in good occlusions. In the second group all M3s had been extracted due to failure to erupt. Mandibular length and morphology and the dimension of the ramus was also studied in the same material. All measurements were made on standard lateral head films. The distance Xi-M2 was found to be significantly greater in individuals with complete dentitions as compared with individuals who had impacted M3s. Furthermore, this variable exhibited significantly greater values in males than in females in both investigation groups. However, in nearly fifty per cent of the subjects with complete dentitions, the M3s had erupted despite a Xi-M2 distance of less than 25 mm. Mandibular length in males was significantly greater in the complete group than in the extraction group. In females no such difference was recorded. The angular measurements used in this study did not differ significantly between the complete and the extraction groups.

Adult↗
PubMed1988

Tooth size, spacing, and crowding in relation to eruption or impaction of third molars.

A study was conducted for the purpose of comparing mesiodistal tooth diameters, sum of tooth widths, and the degree of spacing or crowding in the dentitions of two groups of young adults. The subjects in the first group had complete dentitions including third molars (M3s). In the second group, all M3s had been extracted for failure to erupt. Tooth size and consequently the sum of mesiodistal tooth widths were found to be greater in the extraction group than in the group with complete dentitions. The relationship between tooth size and M3 impaction was most pronounced in female subjects. The sum of mesiodistal tooth widths is apparently one factor of importance in the cause of M3 impaction in women. The results suggest that tooth size in girls could be used at preadolescent age as one predictive variable for third molar eruption. The sexual dimorphism demonstrated regarding the relationship between tooth size and M3 impaction implies that studies in the field of M3 development and eruption should be performed on male and female subjects separately. The dental arches in the extraction group tended to be more crowded than in the group with complete dentitions. However, the differences were small and significant only as they related to the upper arches in males.

Adult↗
PubMed1986

The phospholipase A1 of Trypanosoma brucei does not release myristate from the variant surface glycoprotein.

[3H]Myristoyl-labeled variant surface glycoprotein (VSG) has been isolated from Trypanosoma brucei by reverse phase high performance liquid chromatography and used as substrate for the conversion by trypanosomal enzymes of membrane-form VSG to soluble VSG. Conversion is detected by the release of myristoyl-containing lipids. The major lipolytic enzyme of T. brucei, phospholipase A1, is effective for the hydrolysis of myristoyl esters of p-nitrophenol, in a colorimetric assay. However, the phospholipase is unable to cleave the myristoyl ester linkage of VSG. The phospholipase can be separated from the myristoyl-releasing activity of trypanosome homogenate by centrifugation, affinity chromatography, and anion-exchange chromatography. Elution profiles on anion-exchange high performance liquid chromatography also indicate that the phospholipase is inactive against VSG. A small amount of myristoyl-releasing activity associated with the purified phospholipase is probably due to contamination with a phosphodiesterase which releases myristoyl-containing diglyceride from VSG.

Animals↗
PubMed1984

Isolation of phospholipase A1 from Trypanosoma brucei.

Phospholipase A1 from Trypanosoma brucei brucei has been purified 380-fold by column chromatography on phosphatidylcholine-Sepharose affinity columns followed by DEAE-cellulose anion-exchange chromatography and Sephacryl S-200 molecular exclusion chromatography. Octyl-Agarose hydrophobic column chromatography can be substituted for the PC-Sepharose column. The molecular weight of trypanosomal PLase A1 was found to be 26,000 by SDS-polyacrylamide gel electrophoresis.

Animals↗
PubMed1982

The effect of 50 per cent phosphoric acid on oral soft tissues.

The effect of 50 per cent phosphoric acid on oral soft tissue was studied in two investigations. In the first investigation the buccal mucosa of three rats was studied after contact with phosphoric acid for 1, 5 and 10 minutes respectively. The material of the second investigation comprised of 26 patients from whom 31 pairs of premolars were planned to be extracted for orthodontic reasons. Phosphoric acid was applied for 90 seconds on one tooth and its buccal gingival margin in each pair of teeth. After a period varying between 1 and 7 days the tooth and a section of the gingiva were extracted and prepared for microscopic examination. The second tooth in each pair was the control tooth. The study showed that only a relatively long acid application time resulted in obvious histologic changes in the mucous membrane. The phosphoric acid gave no demonstrable gingival reaction in the patients.

Acid Etching, Dental↗