Search PubMed⌕ Search

Biomedical subjects

R L Van Swol

Publications and source records attributed to R L Van Swol.

At least 19 recordsLinked to original sources
PubMed1996

Clinical evaluation of an ionic toothbrush in the removal of established plaque and reduction of gingivitis.

The clinical effectiveness of a manual ionic toothbrush in the removal of dental plaque and the reduction of gingivitis was evaluated. A double-blind study evaluated the effect of a small, imperceptible electric current on established dental plaque and gingivitis during toothbrushing. Sixty-four adults completed the study. Gingivitis and plaque scores were determined at baseline and after 3 and 6 months. The baseline indices of the two groups were well balanced. At each examination, the participants were instructed how to hold the toothbrush properly and reminded to change brush heads every 4 weeks. Statistically significant improvements in Löe Gingival Index scores were observed from baseline to 6 months between the control and test groups and within the test group. The Quigley-Hein Plaque Index scores also showed a significant improvement from baseline to 6 months between the control and test groups and within the test group.

Adolescent↗
PubMed1993

Collagen membrane barrier therapy to guide regeneration in Class II furcations in humans.

This study was undertaken to evaluate the effectiveness of resorbable collagen membranes in guided tissue regeneration. The study participants were 38 adults with moderate to advanced periodontitis. Each patient had at least one Class II furcation defect which could serve as either a test or control tooth. The cases were randomized prior to selection, so that investigators did not known whether the patient would be a test case or a control case until the time of surgery. Sites were surgically exposed and measurements were recorded from the cemento-enamel junction (CEJ) directly coronal to the furcation area to the alveolar crest, and to the base of the defect. Horizontal furcation measurements were also made, using a color coded furcation probe. The test patients had a trimmed and shaped collagen membrane barrier placed over the prepared furcation area. The control patients received the identical surgical management, except that no collagen membrane barrier was placed. All patients received normal post-surgical care, and at 12 weeks post-surgery, were scheduled for re-entry surgery. The re-entry mucoperiosteal flaps were designed to expose the furcation area for measurements, as described above. There was clinical improvement in all measurements made in both the test and control patients over the 3-month period. The horizontal furcation measurement and the CEJ to base of alveolar defect measurements did yield a statistically significant improvement when comparing the test patients to the controls.

Adult↗
PubMed1990

Biphasic calcium phosphate ceramic combined with fibrillar collagen with and without citric acid conditioning in the treatment of periodontal osseous defects.

The purpose of this study is to determine whether the combination of biphasic calcium phosphate ceramic (BCP) and collagen and citric acid root conditioning would promote accelerated new attachment of periodontal tissue to the root surface in dogs. Intrabony defects were surgically produced for each animal and were made chronic for 16 weeks. These defects were assigned to two study treatment and one control group: ceramic-collagen without citric acid (CO-CE); ceramic-collagen with citric acid (CO-CE-CA); and control (surgical debridement and root planing only). Results showed that all groups gained new attachment level as demonstrated both clinically and histometrically. The treatment groups showed a significant mean gain greater than the control (P less than .005), but no significant difference was found between treatment groups. Small areas of ankylosis was also found in both treatments but there was no evidence of active root resorption. It is concluded that the use of combined BCP and fibrillar collagen is beneficial in promoting new attachment of periodontal tissues to the root surface in dogs. Although citric acid root conditioning did as well or better than ceramic and collagen alone, its benefits are still speculative and need further experimentation.

Animals↗
PubMed1987

Connective tissue reactions to 3% tetracycline ointment in rat skin.

The connective tissue reactions to 3% tetracycline ointment were studied in 14 Sprague-Dawley white male rats. Using polyethylene tubes, the ointment was implanted subcutaneously in the pouches surgically created on the backs of the experimental group. Empty tube implants, tubes with the vehicle (vaseline/lanolin), and a sham operation (surgical pouches with no implant) served as controls. The animals were killed on day 14 and tissue blocks were taken containing the tubes and a generous amount of the peripheral connective tissue. The connective tissue surrounding the tube opening furthest from the surgical incision was histologically examined for the severity of tissue reaction (STR), the number of inflammatory cell infiltrates (II), and the spread of the reaction area (RSI). The data were statistically analyzed. The sham operation group showed minimal inflammatory response. All three parameters (STR, II, RSI) were significantly greater in the tetracycline group when compared with the empty tube group at 0.05 level of significance. There were significant differences between the mean values of the STR and RSI scores in the tetracycline and vehicle groups (groups 1 and 2). The vehicle group (group 2) had significantly higher STR and II values than the empty tube group (group 3); however, the RSI scores were not statistically different. Necrosis was observed in the reaction site in group 1 and vacuole-containing macrophages were noted in groups 1 and 2. This study, although an animal investigation, questions the use of topical 3% tetracycline ointment on sutured surgical flaps.

Animals↗
PubMed1987

Periodontally diseased vs. normal roots as evaluated by scanning electron microscopy and electron probe analysis.

A scanning electron microscope and electron probe study was carried out to compare root structure from deep within periodontal pockets with roots exhibiting no periodontal disease. To eliminate the possibility of extraneous ion introduction or deletion, no attempt was made to subject the roots to fixation, embedding, or dehydration prior to sectioning and viewing in the electron microscope. Mineral content and concentration were determined with an electron probe on two specimens per tooth. On one specimen, only the external cemental surface was analyzed. On an adjacent cross section, readings were taken from the surface and at incremental depths into the root. A nonparametric statistical analysis compared diseased with nondiseased roots. The following conclusions can be drawn from the study: (1) Consistent and repeatable qualitative electron probe analyses can be performed on human teeth with minimal specimen preparation. This gives a more accurate assessment, since the integrity of the crystalline structure is not disrupted. (2) Minerals consistently found were P, Ca, Cu, Zn, Mg and Na. They were in similar concentrations throughout the area analyzed. (3) Mg and Cu showed higher values in the nondiseased teeth. (4) There were no differences in concentrations for Ca, P, Zn, and Na between roots exposed to a periodontal pocket and nondiseased roots.

Copper↗
PubMed1984

Histologic analysis of the hyperplastic maxillary anterior frenum.

Fifteen biopsy specimens from hyperplastic maxillary anterior freni were examined histologically by three investigators, and tissue components were subjectively rated on a predesigned scoring sheet. The presence of calcification and ossification associated with high levels of inflammatory infiltrates and reactive connective tissue confirm the fact that surgical excision of the hyperplastic frenum is warranted.

Adolescent↗
PubMed1980

Immunoglobulins in periodontal tissues. II. Concentrations of immunoglobulins in granulation tissue from pockets of periodontosis and periodontitis patients.

In recent years evidence in the literature has indicated that the immune response may play an important role in the initiation and progression of the periodontal diseases. A study was initiated to determine the IgA, IgG, and IgM concentrations in the granulation tissue removed from deep infrabony pockets of patients with periodontosis and advanced periodontitis. Comparison of mean immunoglobulin levels between the periodontosis and periodontitis groups revealed a statistically significant increase (P less than 0.05) for IgG in the granulation tissue from the periodontosis group. The possible implications of these findings are discussed.

Adolescent↗