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Browsing by Author "Shafer, William G."
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Item A comparison of maxillary arch form between groups of cerebral palsied and normal children(1971) Dummett, Clifton Orrin, Jr.; Gish, Charles W., 1923-; McDonald, Ralph E., 1920-; Roche, James R., 1924-; Shafer, William G.; Garner, La Forrest Dean, 1933-The purpose of this study was to compare the maxillary dental arch form and palatal vault form between 98 cerebral palsied and 76 normal children. All subjects were divided into three categories based on their dental eruption. The cerebral palsy subjects were further divided into the regional classifications of diplegia, paraplegia, hemiplegia, and quadriplegia, and the descriptive classifications of spasticity, athetosis, and mixed. The maxillary dental arch form was described by an index number which reflected intercuspid width, intermolar width, anterior-posterior length, and degree of divergence of the posterior segments. The palatal vault form v1as described by the angle of divergence of the palatal walls at an established reference point from a cross-sectional view. All measurements were made from study models and Xerox photocopies of study model cross-sections. In addition, those occlusal discrepancies that were thought to influence arch form, i.e., posterior unilateral and bilateral crossbite, anterior crossbite, anterior open bite, and posterior dental asymmetry were tabulated. Statistical analysis of the results revealed no significant difference in maxillary dental arch form between the cerebral palsied and normal children. The same held true for palatal vault form. Significant differences did occur between primary, mixed, and permanent dentitions for both cerebral palsied and non-handicapped groups. The results suggest that the neuromuscular handicap has little effect on the form of the maxillary dental arch. On the basis of this study, it appears that there is no particular type of maxillary arch form that is peculiar to cerebral palsy.Item A critical clinical and television radiographic evaluation of indirect pulp capping(1967) Traubman, Lionel; Bixler, David; Shafer, William G.; Phillips, Ralph W.The purpose of this study was to quantitatively measure the rate and amount of calcification and secondary dentin deposition below deep carious lesions of otherwise radiographically and clinically sound teeth treated by calcium hydroxide - methyl cellulose indirect pulp capping. Standardized, reproducible serial radiographs of 50 treated young posterior teeth were exposed preoperatively at one, three, six, nine and, in some cases, 12 months. At the final appointment, the silver amalgam restorations were removed and all residual caries was excavated. A barium sulphate radiographic indicator paste identified the pulpal floor level at the first and last appointments. Ninety per cent of the teeth studied remained asymptomatic and were not pulpally exposed. Television density and linear measurement instrumentation was utilized to register calcification changes, pulpal floor thicknesses, and secondary dentin deposition. Following treatment, increased secondary dentin deposition and Calcification activity, or sclerosis, was initiated. Higher levels of calcification activity were related to increased thickness of pulpal floors, but this dimension had little influence on the total amount of reparative dentin formed. The rate of reparative dentin formation was highest during the first month and steadily diminished with time. Calcification activity experienced a cyclical change, or "exchange," with an initial activity peak. This was followed by an apparent, but temporary mobilization of mineral content •out of the affected dentin. With time, a steady rise in calcification level was observed. Measurement of longitudinal records showed that apparent pulp exposures can be avoided by allowing significant amounts of protective secondary dentin to form, before complete caries excavation.Item Effect of a stable 30 per cent stannous fluoride solution on recurrent caries around amalgam restorations(1968) Alexander, William Everett, 1938-; Swartz, Marjorie L.; Garner, La Forrest Dean, 1933-; Shafer, William G.This was a study to evaluate the effectiveness of a stable 30 per cent stannous fluoride solution on recurrent caries around the margins of amalgam restorations. Two hundred ninety deciduous and permanent teeth were restored in 34 children, ages six to nine years. Cavity preparations were treated with either stable 30 per cent stannous fluoride solution or a placebo solution (double blind technique) prior to the placement of amalgam restorations. A comprehensive coded system was used to record the description and position of conditions associated with recurrent caries after a one-year period. Children receiving the stannous fluoride treatment experienced a 58.9 per cent reduction in recurrent caries when compared to the control children. The children receiving the stannous fluoride treatment showed a 60.7 and 46.7 per cent reduction in recurrent carious lesions in permanent and deciduous teeth, respectively, when compared to the control children. The reduction in recurrent caries was attributed to the anticariogenic effect of the stannous fluoride treatment. Conditions associated with recurrent caries were mainly inadequate extension in fissures and grooves, overextension of the cavity preparation, marginal fractures of enamel and amalgam, marginal excess, and deterioration of the amalgam margin. Recurrent caries around the margins of restorations appeared to depend on (1) the caries susceptibility of the adjacent tooth structure,(2) the extension of the cavity preparation, and (3) the condition of the amalgam-enamel margin.Item Effects of cardiac glycosides on the composition of whole-mixed human saliva(1978) McDonald, John S., 1947-; Shafer, William G.; Barton, Paul; Bixler, David; El-Kafrawy, Abdel Hady, 1935-; Standish, S. Miles, 1923-2003Electrolyte levels were measured in whole-mixed human saliva collected from cardiology out-patients, to investigate any salivary electrolyte changes occurring in such patients after digitalization. Several recent reports have indicated that clinical symptoms of digitalis intoxication were associated with increased saliva concentrations of K+ and/or Ca++. Because salivary glands contain a highly active Na+, K+-ATPase it seemed logical that these and other salivary electrolytes might be predictably affected by the circulating levels of digitalis. Patients receiving digitoxin (Dtxn) had a higher concentration of Salivary K+ and Ca++ (25.8 ± 2.2 and 2.2 ± 0.2 meq/l, respectively), than the controls not receiving cardiac glycosides (20.1 ± 1.4 and 2.0 ± 0.1 meq/1, respectively). A similar pattern was not found for patients receiving digoxin (Dxn), although the mean Ca++ concentration for females in this group was significantly elevated (control: 1.7 ± 0.2; Dxn: 2.4 ± 0.2 meq/1). The mean serum concentration (ng/ml) of Dtxn was 20.3 ± 1. 9; of Dxn, 1.4 ± 0.2. No change was found in P04, and protein concentrations, or in salivary flow rates between control and experimental groups. The results suggest that salivary electrolyte changes occur after digitalization, but that these changes do not adequately reflect the serum level of digitalis in individual patients. This study was supported in part by PHS 80l-RR5312.Item A histological study of gingival implants into the dental pulp and connective tissue of dogs(1967) Henry, Millicent, 1936-; Mitchell, David F.; Shafer, William G.; Bixler, David; Garner, La Forrest Dean, 1933-; McDonald, Ralph E., 1920-Item Orthodontic Movement and Return of the Root Apex Through the Cortical Plate in the Macaque Speciosa Monkey(1970) Wainwright, W. Michael; Garner, LaForrest D.; Shafer, William G.; Cunningham, Donald M.; Norman, Richard D.During orthodontic therapy, the apices of teeth are sometimes moved or tipped against and even through the cortical plate of bone. This may be a final tooth position or the root may then be brought back into cancellous bone. The purpose of this study was to observe histologically the effects of these movements and of retaining the root in these positions. Four Macaque Speciosa monkeys were used. Their ages corresponded to late adolescence in the human. The force system used to achieve the desired tooth movement on the animals' teeth was calculated from a force system which from clinical experience is considered to be optimal in root movement in humans. This force system was kept constant. Procion Brilliant Red H-8BS was used as a vital marking agent and was administered once to each animal prior to the last stage of movement in each case. As the root apex penetrated the cortical plate, the buccal surface was the only root surface that became devoid of bone. There was considerable proliferation of cortical plate which "followed" the root and maintained its relationship to bone on the remaining root surfaces. During a four month retention period there was continued osteogenesis of the buccal surface of the cortical plate, but the root apex was not completely covered. Bone apposition also occurred on the lingual surface of the buccal plate and there was remodeling of the osteophytes. As the root was moved back and retained, there was complete repair of the perforation site with further slight thickening of the cortical plate. Root resorption was present on the buccal surface when it was under pressure, and the lingual surface on reversal of the force system. The resorption was increasingly severe towards the root apex. Although the tooth movement was 50 percent faster on the reversal movement, the severity of resorption was comparable on buccal and lingual surfaces. Cellular cemental repair was considerable and was most marked at sites of greatest recent root resorption and on the tension side of the tooth in movement. Less cemental deposition occurred on the mesial and distal root surfaces. Since the appliances were reactivated monthly, areas of hyalinization were rare. There was no inflammation due to tooth movement and the pulp tissue was normal in all cases.Item Pulp reaction to anorganic bovine dentin(1967) Walshe, Martin J.; Norman, Richard Daviess, 1927-; Shafer, William G.; Gish, Charles W., 1923-A study was made to determine if heterogenous dentin, devoid of its antigenic potential, would stimulate reparative dentino-genesis in the dental pulp. The teeth of two monkeys were capped with bovine dentin mixed with methyl cellulose and histologic analysis was made at 21 and 42 days post-operatively. At the 21-day interval, seven of the 17 teeth capped with the experimental material were successfully repaired with atubular dentin. The remaining 10 teeth showed varying degrees of inflammation and repair. The teeth of the second animal (42 days) were stained for bacteria as an additional diagnostic tool. A direct correlation was found between delayed healing and inflammation and presence of bacteria in the pulp. No bacteria were found in pulps which were successfully repaired. It was concluded that anorganic bovine dentin seemed to induce calcific repair of the dental pulp in the absence of bacteria. Autogenous dentin chips appeared to have the same effect. The importance of including a bacteriologic stain in the histologic analysis of pulp capping studies was demonstrated.Item The Integumental Profile : A Study of Black American Children(1974) Sturrup, Randolph W.; Garner, LaForrest D.; Shafer, William G.; Shanks, James C.; Potter, Roario H.; Barton, PaulThis study was undertaken to obtain standards on soft tissue facial contour in black American children, based on an analysis of cephalometric lateral headplates. A sample of black children (10 boys and 10 girls between 10 and 14 years of age) was compared to a white sample of comparable age. The following 20 profile measurements were made and subjected to statistical analysis: Upper lip protuberance, lower lip protuberance, soft tissue profile, anterior nose length, nasal angle, naso-labial angle, upper lip inclination, lower lip inclination, esthetic plane to upper lip, esthetic plane to lower lip, mandibular sulcus, maxillary sulcus, upper lip length, upper lip to upper incisor, lower lip length, height of soft tissue chin button, point A to subnasale, upper lip thickness, and soft tissue chin button. There were significant differences between the white and black samples in all but the following five measurements: Soft tissue convexity, maxillary sulcus depth, upper lip to upper incisor, and soft tissue chin button. There were no statistically significant differences between the measurements for black males and females except that the measurement from upper lip to maxillary incisor was significantly greater in the black male. On the basis of the findings in this limited study, it appears that morphologic standards derived from one ethnic group should not be applied to individuals of another ethnic group.