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Biomedical subjects

W K Duncan

Publications and source records attributed to W K Duncan.

At least 19 recordsLinked to original sources
PubMed1994

Dentin dysplasia type I. Radiologic and genetic perspectives in a six-generation family.

This is a report of a kindred of at least 181 members, of whom 35 exhibit or are reported to have dentin dysplasia type I. Six others are suspected of having the condition. Radiographic evidence that included obliterated or semilunar pulp chambers and short or undeveloped roots confirmed the diagnosis in 18 persons. The autosomal dominant mode of inheritance has been confirmed. One hundred percent penetrance has been demonstrated. There were insufficient data to determine the degree of expressivity.

Adult↗
PubMed1994

Chloral hydrate sedation: a simple technique.

Chloral hydrate is an oral sedative commonly used in pediatric dentistry when providing extensive treatment in the young child. This article reports the results of a clinical trial using an orally administered dose of chloral hydrate at 75 mg/kg of body weight plus nitrous oxide and oxygen. A method for administering the drug that minimizes initial drug expectoration and vomiting is also presented. Because a reliable method for delivery of chloral hydrate is essential in a study of the ideal effective dose, the authors describe a technique that makes this portion of the treatment process as pleasant as possible by associating the drug with a product known to be pleasing to most children of this age group. The results of the clinical trial of 50 patients revealed that 29 children (58%) slept through the entire procedure and 14 (28%) of the children presented only mild resistance either during anesthesia and/or treatment. If some mild resistance is acceptable to the practitioner then there was an approximately 85% success rate. The authors concluded that chloral hydrate used at a 75 mg/kg dose and supplemented by nitrous oxide/oxygen is a safe and reliably effective sedative for the preschool child.

Anesthesia, Dental↗
PubMed1994

The cost of nursing caries in a Native American Head Start population.

Nursing caries is a unique form of caries caused by prolonged exposure to pooled fermentable liquids and a lack of salivary flow during sleep. It is characterized by extensive destruction of the primary maxillary incisors generally beginning on the facial or lingual smooth surfaces. Nursing caries appears to have a particularly high prevalence in Native American populations and can be very costly to restore. The purpose of this study was (1) to determine the prevalence of nursing caries in a Mississippi Choctaw Indian Head Start program and (2) to determine the dollar costs of restoring nursing caries in a similar population. In part 1 of this study, 2 dentists independently examined 629 Native American Head Start children ranging in age from 3-5 years. It was found that 50.2% of these children had nursing caries. In part 2 of this study the cost of treating nursing caries in a Choctaw Indian population that ranged in age from 2-5 years was determined. It was found that the mean total cost of restoring a nursing caries patient requiring general anesthesia to provide treatment was $2,141.75. It was also determined that the mean cost of providing treatment for those children not requiring general anesthesia was $311.55. This study concluded that there was an extremely high prevalence of nursing caries in this Choctaw Indian Head Start population and that funds directed toward prevention would be a wise investment and that renewed and innovative efforts toward preventing nursing caries in these populations are indicated.

Bottle Feeding↗
PubMed1992

The Sturge-Weber syndrome: a case involving a 13-year-old black male.

A 13-year-old black male patient with Sturge-Weber Syndrome is presented. The report describes the classic presentation of the syndrome, emphasizing the oral manifestations. The case presentation includes a discussion of the differential diagnosis of gingival enlargement, and suggestions for subsequent therapy.

Adolescent↗
PubMed1991

Dentin dysplasia: review of the literature and a proposed subclassification based on radiographic findings.

The literature is reviewed to determine the radiographic appearance of the reported cases of dentin dysplasia. The sometimes confusing nomenclature is rationalized. Four distinct forms of dentin dysplasia type I and one form of dentin dysplasia type II are identified. There seems to be no need to identify more than two distinct types of this relatively rare inherited defect of human dentin, but a proposed subclassification of type I dentin dysplasia could make identification of the two types easier.

Dental Pulp↗
PubMed1991

Type I dentin dysplasia: report of two cases.

Dentin dysplasia is a rare developmental disturbance of dentin affecting approximately 1:100,000 people. It has been classified as an autosomal dominant disease. Two distinct forms of dentin dysplasia have been described. As more cases of dentin dysplasia were reported these categories seemed inadequate; subclassification of type I dentin dysplasia were proposed based on root length and the presence or not of a pulpal remnant. This paper presents two cases demonstrating the classic features of type I dentin dysplasia in the mixed and permanent dentitions and discusses the suggested subclassifications. The authors suggest that while differences in root length may be useful in determining treatment options, thinking of these variables as separate types of dentin dysplasia is not warranted at this time. Justification of a subcategory of type I dentin dysplasia should be based on a different disease process, different histology, significantly different symptoms, or different etiologies, and until researchers can clearly prove from a genetic or chromosomal standpoint that the subcategories are separate entities, we should accept, as we do for many other genetic disorders, that some patients are more severely affected than others.

Adult↗
PubMed1990

A simplified hypoplasia index.

A simplified hypoplasia index for deciduous teeth has been developed. The index utilizes a two-digit system to signify the type and severity of the hypoplastic lesion. The types of lesions recorded are primary canine hypoplasia (PCH) and linear enamel hypoplasia (LEH). The severity ranges from minimal to severe and accounts for the presence of dental caries, dental restorations, and recurrent caries. To determine the reliability of the index, two tests were conducted. The first measure was a repeat reliability coefficient (test-retest) to calculate the stability of the instrument. This measure was calculated for two populations by two examiners under the same examination conditions and exams were conducted seven weeks apart. The second measure calculated the interrater reliability (standardization). Test results were analyzed by employing the Pearson product moment correlation. The repeat reliability coefficients were .75 (P less than or equal to .0001) and .74 (P less than or equal to .0001). The interrater reliability coefficient was .87 (P less than or equal to .0001). These data seem to indicate that the index is reliable over time and between examiners.

Dental Caries↗
PubMed1989

Primary canine hypoplasia in Head Start children.

Primary canine hypoplasia is an incomplete or defective development of the enamel matrix. The lesion is located on the labial surface and is seen more frequently on mandibular teeth. The purpose of this preliminary study was to determine the prevalence of this lesion among Head Start children. During a dental needs assessment of Mississippi Head Start children, 371 children from 11 centers were examined for this lesion. Of the centers, four were located in optimally fluoridated communities, and six were located in fluoride-deficient communities. Ages ranged from three to five years. There were 206 males and 165 females, 334 black and 37 white children. At ten centers all children were black, while all children at one center were white. Results indicated no significant differences in the black population between fluoridated (38.2%) and fluoride-deficient (36.3%) communities (P = .729) or between males (36.8%) and females (37.6%) (P = .877). When data were collapsed on sex and fluoridation status, the racial differences were highly significant (P = .001). The prevalence rate of dental caries associated with primary canine hypoplasia was 26.0 percent. These preliminary data indicate that the presence of primary canine hypoplasia may result in an increased potential for the tooth becoming carious.

Black People↗
PubMed1988

Eosinophilic granuloma.

Eosinophilic granuloma is said to be the most benign disorder of the triad commonly known as histiocytosis X. There has been, and still is, confusion about the terminology describing this entity. This article reviews the literature on histiocytosis X, with particular emphasis on eosinophilic granuloma and its oral manifestations. The case of a 22-month-old male child with an eosinophilic granuloma of the right mandible is presented. The diagnostic and treatment methods are reviewed and discussed. During the 4 years that the case has been followed there has been progressive healing of the lesion, but other manifestations of the disease process and of the surgical treatment have become evident. The need for close dental as well as medical follow-up in cases involving the dental structures is stressed.

Cell Nucleus↗
PubMed1987

Bilateral fusion and gemination: a literature analysis and case report.

The dental literature concerning the bilateral presentation of fusion and gemination is reviewed and analyzed. Tables are presented to show the prevalence and distribution of these anomalies in both the primary and permanent dentitions. In addition, the first prevalence statistics for the bilateral occurrence of fusion and gemination in the primary and permanent dentitions are determined. The first case of bilateral fusion of mandibular primary incisors to be reported in 13 years is presented. The presence of all four succedaneous incisors and the diagnosis of bilateral fusion are confirmed radiographically. The developmental concerns and possible sequelae of bilateral fusion and gemination are also discussed.

Child, Preschool↗
PubMed1983

Management of the nonerupted maxillary anterior tooth.

The noneruption of maxillary anterior teeth, particularly the canine, is a common problem. The cause of the noneruption is multifactorial but almost always involves a lack of space. The literature presents an active and a passive form of orthodontic treatment and has recently stressed the periodontal management of these teeth. Two cases are presented. In both cases the orthodontic techniques of regaining space and providing traction on the unerupted tooth are described. A free gingival graft is used in one case and an apically repositioned flap in the other to achieve a healthy periodontium. The advantages and disadvantages of the techniques used as well as their rationale are discussed.

Adolescent↗
PubMed1981

Ectopic eruption of the mandibular first permanent molar.

In this case, a clear pathway for eruption was provided for the mandibular left first permanent molar by reducing the distal surface of the primary molar. The occlusal surface was also surgically uncovered to remove any possibility of a mucosal barrier. It was thought that the loss of arch length was not too great a sacrifice if the tooth could be brought into occlusion. The tooth proved not to be ankylosed and was, therefore, able to erupt into occlusion. The patient may have some crowding in the mandible; however, it appears to be within normal limits and no further orthodontic treatment is anticipated. When the relative simplicity of treatment is weighed against the severity of the consequences of untreated cases of ectopic eruption, it is suggested that treatment should be started as soon as the condition is diagnosed, to establish a normal eruption pathway and avoid any detrimental effects on a developing occlusion.

Child↗
PubMedDate not supplied

Prevalence of primary canine hypoplasia of the mandibular teeth.

The purpose of this study was to determine the prevalence of an uncommon lesion of the primary mandibular canines (primary canine hypoplasia), and its association with age, race, gender, dental caries, fluoridation status of the drinking water, breast-feeding, and geographic location. The study population comprised 2686 randomly selected children, black and white, 4 and 8 years old, who were enrolled in accredited private and public preschools and elementary schools in Mississippi. There were 1318 males and 1368 females, 1289 white children and 1397 black children, 1353 4-year-olds and 1333 8-year-olds. Results indicate that an association exists for race (P = 0.0001), gender (P = 0.01), and dental caries (P = 0.0001), but not for age (P = 0.07), geographic location (P = 0.73), fluoridation status of the water supply (P = 0.145), or breast-feeding (P = 0.392). The prevalence rate of primary canine hypoplasia was 33.2% for black children and 17.2% for white children. These data indicate that this lesion is significantly more prevalent in blacks than whites, and that teeth with this lesion have a greater probability of developing dental caries.

Black People↗