Browsing Oral Health Sciences by Title
Now showing 1 - 20 of 280
Results Per Page
ItemAbnormal behavioural patterns in dogs with cleft palates(1973) Dreyer, C. J.; Preston, C. B. ItemAccurate diagnosis of occlusal carious lesions - a stereo microscope evaluation of clinical diagnosis(2002) Grossman, E. S.; Cleaton-Jones, P. E.; Côrtes, D. F.; et alThis study was undertaken to validate the caries status of 214 teeth by serial sectioning and microscopy after caries diagnosis using four methods. Two hundred and fourteen extracted human teeth with varying degrees of caries were mounted in the jaws of nine training manikins. All tooth surfaces were examined and recorded for caries by four dentists using bitewing radiographs, fibre-optic transillumination (FOTI), mirror alone and a mirror and sharp probe on two separate occasions. Thereafter the teeth were serially sectioned and assessed microscopically for depth of caries lesion on a graded score of 0-7. This report assessed the diagnostic outcome of 2,183 observations for occlusal surfaces. Sound diagnoses predominated over unsound until caries was present in the inner half of dentine. Specificity was between 90% and 95% and sensitivity 26% and 50% depending on which diagnostic method was used and where the sound/unsound threshold was set. Negative and positive predictive values were similarly influenced and varied between 53% and 80% and 73% and 90%, respectively. Probit analysis showed no significant differences (P < 0.05) between examiners and diagnostic methods. Diagnosis of occlusal caries undertaken in an in vitro simulated clinical situation is inaccurate until the caries lesion extends deep into the dentine no matter which of the four methods was used. ItemAdvances in osteogenin and related bone morphogenetic proteins in bone induction and repair(1992) Luyten, F. P.; Cunningham, N. S.; Vukicevic, S.; et alBone matrix is a repository of growth and differentiation factors as demonstrated by the induction of local cartilage and bone formation in rats. The bone inductive activity, termed osteogenin, can be dissociatively extracted, and it was isolated by heparin affinity, hydroxyapatite and molecular sieve chromatography. Osteogenin has been purified to homogeneity from bovine bone matrix and the sequences of several tryptic peptides have been determined. The sequences were similar to portions of the amino acid sequence deduced from the cDNA clone of bone morphogenetic protein-3 (BMP-3). The carboxyl-terminal quarter of osteogenin has sequence identity to the corresponding regions of two related proteins BMP-2A and BMP-2B. The bone inductive proteins are members of the TGF-beta superfamily, by virtue of the location of the highly conserved cysteines in their carboxyl-terminal region. Osteogenin and related BMPs initiate cartilage and bone formation in vivo. The study of the mechanism of action of these proteins will add considerable new information on the molecular signals controlling endochondral bone formation. In vitro data indicate that osteogenin stimulates the expression of the osteogenic and chondrogenic phenotypes. Our results demonstrate their profound influence on proteoglycan synthesis and degradation in bovine cartilage explant cultures. High affinity specific binding sites have been identified in both MC3T3 cells and articular chondrocytes. In vivo experiments demonstrate the efficacy of primate osteogenin in restoring large calvarial defects in adult baboons, establishing a primary role for osteogenin in therapeutic initiation and promotion of osteogenesis. ItemAirway status in civilian maxillofacial gunshot injuries in Johannesburg, South Africa(2002) Tsakiris, P.; Cleaton-Jones, P. E.; Lownie, M. A.BACKGROUND: Airway management of the maxillofacial gunshot injury constitutes a critical decision and an area that requires review in the context of civilian injuries. Most of our knowledge is extrapolated from military experience, which constitutes a different trauma patient group. This paper reports a retrospective survey of airway status in relation to maxillofacial gunshot injuries. The objective is to correlate clinical findings with treatment decisions. METHODS: A survey was done of 11,622 archived maxillofacial surgery records (1987-1992) in the three academic hospitals in Johannesburg. RESULTS: There were 211 maxillofacial gunshot injuries, for which 92 patient records had sufficient detail for inclusion in the analysis. The typical patient was a black male aged 20-29 years, shot with a low-velocity bullet of 0.38 calibre, admitted to hospital the day of the injury, operated on within 4 days, and discharged 4 days later. The airway was threatened in 20/92 cases at admission; 12/20 cases were treated with oro-or nasotracheal intubation, and 9/12 later had elective tracheostomies; 8/20 needed immediate surgical airways, 5 tracheostomies and 3 cricothyroldotomies (all later converted to tracheostomies). Three of thirty-seven patients with normal airways on admission later required emergency tracheostomy. CONCLUSIONS: An abnormal airway was significantly more likely after a high-velocity injury, and when the tongue, floor of mouth, midline or bilateral facial skeletal bones were involved. ItemAlkali resistant haemoglobins from normal and sickle cell bloods(1955) Anderson, C. G. ItemAlveolar dehiscence and fenestration in dried South African Negro maxillae(1981) Volchansky, A.; Vieira, E. ItemAnalyses of marginal seals in aged amalgam restorations using extraction replicas(1984) Grossman, E. S.; Witcomb, M. J.; Jodaikin, ASince dental amalgam does not bond chemically to tooth structure, a microcrevice is present at the amalgam/tooth interface of a freshly placed restoration. This gap is of sufficient width to allow fluids and microorganisms to pass along the cavity walls and thereby facilitating the recurrence of dental caries, which accounts for the majority of amalgam restoration replacements. ItemAnalysis of attendance rates at Soweto dental clinics 1995 - 2002(2004) Harkison, B. N.; Cleaton-Jones, P. E.BACKGROUND: Patient attendance rates at Soweto dental clinics increased during the year after the implementation of free primary oral health care in 1995. OBJECTIVE: This study was performed to examine if the attendance rates continued to increase between April 1995 and March 2002. MATERIALS AND METHODS: Monthly clinic records were used to record casual (pain and sepsis treatment) and booked patient attendance (restorative, prosthetic and orthodontic treatment) and number of dental operators in the nine primary health care clinics and one hospital clinic in Soweto. Data were analysed with SAS and Prism software. RESULTS: Total patient attendances in the primary health care clinics significantly increased from 6,161 in 1995 to 10,519 in 2002 (P<0.05) due to an increase in casual patients Booked patients decreased and patients treated per operator increased. In the hospital clinic the casual patient attendances decreased but booked patients significantly increased (P<0.005). CONCLUSIONS: Patient attendance rates increased between 1995 and 2002 with an increase in dental operator workload. ItemAn analysis of fractures of the facial skeleton in three populations in the Johannesburg urban area(1985) Beaumont, E.; Lownie, J. F.; Cleaton-Jones, P. E.; et al ItemAnticipated changes in caries prevalence in South Africa(1979) Cleaton-Jones, P.; Richardson, B. D.; Walker, A. R. P. ItemAssessment of periodontal status and treatment needs of a disabled population using the CPITN(1999) Bamjee, Y.; Chikte, U. M. E.; Cleaton-Jones, P. E.The Community Periodontal Index of Treatment Needs (CPITN) was used to assess the periodontal status of 213 handicapped persons attending seven institutions in Johannesburg. Fewer than 2% had healthy mouths, 8% had bleeding only, followed by calculus (46%), shallow pockets (40%) and deep pockets (4%). The mean number of sextants with bleeding or higher score was 5.9. Oral hygiene instruction was indicated for 98% and prophylaxis for 90% of the participants. The CPITN was easily used in the disabled population but may overestimate treatment need in view of the current understanding that periodontal disease does not automatically progress from a low CPITN level to the next. A more appropriate measure of treatment need in handicapped persons is required Item ItemThe bacteriology of sheep periodontitis with special reference to Actinobacillus actinomycetemcomitans(1986) Dreyer, W. P.; Parker, J. R.; Ebersole, J. L.; et al ItemBase solubility and marginal sealing in amalgam restored teeth(1991) Grossman, E. S.; Witcomb, M. J.; Matejka, J. M. ItemThe bearing of dietary sucrose on the deciduous dentition of pre-schoolchildren in the Traansvaal(1979) Richardson, B. D.; Cleaton-Jones, P. E.