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Biomedical subjects

F A Carranza

Publications and source records attributed to F A Carranza.

At least 37 records · Page 2Linked to original sources
PubMed1986

Bone formation within porous hydroxylapatite implants in human periodontal defects.

Tissue samples from three subjects who had periodontal defects treated with a porous hydroxylapatite implant were investigated using light microscopy and scanning electron microscopy. The 3-month specimen showed connective tissue infiltration through the pores and a narrow zone of bone formation present along the walls of the pores. At 4 months, continued evidence of bone deposition was present with osteocytes, osteoblasts and organization of collagen fibers apparent throughout the implant. The 6-month implant had further evidence of continued bone formation with lamellar bone being the major component within the pores.

Alveolar Process↗
PubMed1986

The presence of bacteria in the oral epithelium in periodontal disease. II. Immunohistochemical identification of bacteria.

Serial histological sections of gingiva obtained from each of six advanced adult periodontitis, two localized juvenile periodontitis and two periodontally healthy patients were used for specific identification of bacteria within the oral epithelium and adjacent connective tissue. Healthy gingival biopsies served as controls. Sections from patients and control biopsies were Gram-stained and also screened with antibacterial sera associated with the peroxidase immunocytochemical technique for specific bacterial identification. The "Pop-off" electron microscopic technique was also used to further demonstrate the bacterial nature of peroxidase-stained material. In addition, the possible correlation between bacteria and areas of possible reduced keratinization was investigated. The results showed that sections of orthokeratinized healthy gingiva did not contain bacteria. Gram-stained sections from diseased sites contained large numbers of bacteria in the oral epithelium and adjacent connective tissue. Bacteroides gingivalis and to a lesser extent Capnocytophaga gingivalis were found in periodontitis, and Actinobacillus actinomycetemcomitans was found in juvenile periodontitis when the immunoperoxidase technique was used. The bacterial nature of peroxidase-stained material was confirmed by the "pop-off" technique. In the disease biopsies, bacterial presence was correlated with areas of reduced amounts of keratin suggesting that the oral epithelium may be a portal of entry for bacteria into gingival tissues.

Actinobacillus↗
PubMed1986

The role of the specialist periodontist.

The major portion of periodontal care of the population belongs in the hands of the general dentist. This is because of the overwhelming number of patients with periodontal disease and the intimate relationship between the periodontal condition and restorative dentistry. The probable increase, in the near future, in the number of patients with periodontal problems will necessitate a greater understanding and an increased level of expertise for their solution on the part of the general practitioner of dentistry. However, there will always be a need for specialists to treat particularly difficult cases, patients with systemic health problems and situations in which complex prosthetic construction requires absolute assurance of reliable results.

Anti-Bacterial Agents↗
PubMed1985

The presence of bacteria within the oral epithelium in periodontal disease. I. A scanning and transmission electron microscopic study.

The presence of bacteria within the gingival oral epithelium and adjacent connective tissue in cases of periodontitis and localized juvenile periodontitis have been described using scanning and transmission electron microscopy. The following bacterial morphotypes were identified: cocci, short rods, filaments and few spirochetes in periodontitis and mainly coccobacillary-shaped bacteria in localized juvenile periodontitis. Also Mycoplasma-like structures were identified in the localized juvenile periodontitis cases. Tunnel-like formations at different depths of the oral epithelium contained higher numbers of bacteria than those seen on the adjacent oral surface. Identification of specific bacteria in the oral epithelium may have important pathogenic and therapeutic implications.

Aggressive Periodontitis↗
PubMed1985

The use of a porous hydroxylapatite implant in periodontal defects. I. Clinical results after six months.

Twenty-five patients with advanced periodontal destruction were used in the study. Following initial therapy, two angular interproximal defects were selected in each patient. During flap surgery a porous hydroxylapatite implant shaped to fit the periodontal defect was placed in one defect, the other defect was used as nonimplanted control. The material used for implantation was a hydroxylapatite replicate of coral from the genus Porites, with a pore size of 190 to 220 micron. Clinical parameters were measured prior to flap surgery for each of the defects. An occlusal acrylic stent was used to give a stable reference point for pocket depth, attachment level and gingival margin height measurements. Also gingival fluid, gingival inflammation, plaque index and tooth mobility were recorded. Periapical radiographs using a standardized positioning device were also taken. At the time of surgery, the depth of the osseous defect and the height of the alveolar crest were recorded. After 6 months the clinical measurements were repeated and a re-entry surgery was carried out in 15 selected sites. Results showed that the porous implant produced statistically significant reduction in pocket depth, in the depth of osseous lesion, and a statistically significant gain in attachment level, as compared to control areas.

Adult↗
PubMed1985

Flap technique for periodontal bone implants. Papilla preservation technique.

A new flap design for placement of implants into osseous defects has been described. The flap design can be used in anterior and posterior areas of human subjects. Photographs of representative cases are presented. Wound healing always occurred by primary intention and without evidence of immediate graft exfoliation. Interdental soft tissue craters did not develop, making it easier for patients to maintain optimal oral hygiene. This type of flap design can also be used without grafts in order to improve postoperative soft tissue contour.

Alveolar Process↗
PubMed1984

Relationship of ascorbic acid levels of blood and gingival tissue with response to periodontal therapy.

The effect of ascorbic acid megadoses on gingival clinical parameters and vitamin content of blood and gingival tissue was studied. 10 nondeficient individuals, carefully matched according to age, periodontal status, and oral hygiene level, were divided into 2 groups: one received 250 mg q.i.d. of ascorbic acid and the other a placebo. After 1 week on the tablet all patients were scaled and root planed and received oral hygiene instructions. Blood samples and clinical parameters were obtained at baseline and 2, 6, and 7 weeks after. A gingival biopsy was taken at week 6. Correlations between the clinical parameters and the ascorbic acid levels at the different time periods revealed no significant differences between the vitamin and the placebo groups, therefore suggesting that the use of megadoses of vitamin C in normal human subjects does not have a predictable or strong effect on the gingival response to initial therapy.

Adult↗
PubMed1984

Mycoplasma in periodontal disease. Isolation in juvenile periodontitis.

Mycoplasma have been identified in one case of juvenile periodontitis by size, morphology, hemadsorption and cultural techniques. These microorganisms were found on the surface of the tooth, on the surface of pocket epithelium and invading the gingival epithelium and adjacent connective tissue. These observations suggest the need for further studies on the role of Mycoplasma in the pathogenesis of advanced periodontal infections. The role of Mycoplasma in periodontal disease is discussed.

Adolescent↗
PubMed1984

The influence of trauma from occlusion on the bacterial repopulation of periodontal pockets in dogs.

Pockets were surgically created in the two upper external incisors of four beagle dogs, and a copper band adapted to prevent reattachment. After 4 weeks the copper bands were removed, the teeth scaled and root-planed and crowns placed on both experimental teeth in such a way that one of them was forced bucally when the teeth occluded. An orthodontic appliance anchored in bands cemented to the cuspid teeth brought the tooth back to its original position when disclusion occurred. Experimental time was 12 weeks. Clinical indices and bacterial samples for darkfield examination were taken at baseline and weekly thereafter. The dogs were fed a diet that favored plaque accumulation and no oral hygiene was performed. Surgically created pockets initially became populated by cocci (65%-75%) and small amounts of motile bacteria (12%-15%) including 3% to 4% spirochetes. In 4 weeks the percentage of cocci declined steadily (42%-45%) and motile bacteria increased to 37% to 43% with spirochetes representing 24% to 27%. After scaling and root planing, the number of cocci increased again and motile bacteria declined although the baseline values were not reached. This decline persisted for 2 weeks after scaling. Repopulation of the pocket in traumatized and nontraumatized teeth followed the same initial pattern, taking again 5 weeks to return to prescaling levels. No difference was found between traumatized and nontraumatized teeth. Clinical measurements, however, revealed a statistically greater loss of attachment in traumatized teeth as compared with nontraumatized teeth.

Animals↗
PubMed1983

Comparative study of gingival retraction methods.

The effects of electrosurgery, retraction cord, and the rotary gingival curettage technique were tested clinically and histologically in dogs. Postoperative periods analyzed ranged from 6 hours to 14 days. All methods induced some kind of minor damage. Recession of clinical magnitude was induced only by rotary gingival curettage. Apical migration of the junctional epithelium was not seen.

Animals↗
PubMed1983

Scanning and transmission electron microscopic study of tissue-invading microorganisms in localized juvenile periodontitis.

This transmission and scanning electron microscope study documents the invasion of microorganisms into the gingiva and along resorbing alveolar bone surfaces in a 15-year-old patient with localized juvenile periodontitis. The invading bacteria were mainly Gram-negative fusiform, coccobacilli and spirochetes. Microorganisms identified as Mycoplasma were also found to invade in some areas. Polymorphonuclear neutrophils (PMNs) were seen in association with the bacteria. The majority of bacteria were covered by PMNs and enclosed by the phagocyte but did not appear to lie within phagosomes. High numbers of PMNs were found in the gingival connective tissue inflammatory infiltrate and in the pocket epithelium. Invasion into the gingiva and alveolar bone by bacteria and Mycoplasma in localized juvenile periodontitis may be importance in the therapy of this infection.

Adolescent↗
PubMed1983

The effect of electrosurgery on alveolar bone.

The facial marginal alveolar bone of dogs was exposed with a full-thickness flap and touched by an activated electrosurgery electrode for periods of 0, 1, 5 and 10 seconds. Microscopic results were evaluated after periods ranging from 0 hours to 28 days. Various electrode exposure times produced similar changes in bone and periodontal ligament. The extent of the destruction was greater than that found in surgical areas not exposed to electrosurgery; healing and remodeling phases were also delayed in the electrosurgical sites.

Alveolar Process↗
PubMed1983

The effect of metronidazole on human periodontal disease. A clinical and bacteriological study.

Fifteen female subjects undergoing treatment for nonspecific vaginitis with metronidazole 250 mg q.i.d. for 7 days were studied. Clinical and microbiological evaluations were carried out initially and at 2 and 4 weeks. The following parameters were measured in two quadrants: plaque index, sulcular bleeding index, pocket depth, attachment level and amount of gingival fluid. Dark field microscopy was used to quantitate the plaque constituents. One quadrant was subjected to root planing at the initial visit; the other quadrant received no therapy. No oral hygiene instructions were given. All the clinical parameters were significantly reduced in all areas. Gingival fluid, sulcular bleeding index and pocket depth showed greater improvement in the root-planed quadrant compared to the nonroot-planed quadrant. Dark field microscopy showed decreases in fusiforms, curved rods and spirochetes in all areas with a concomitant increase in cocci. The root-planed quadrant showed no significant differences in microbiological aspects when compared to the nonplaned quadrant. Clinically, metronidazole therapy resulted in improvement of periodontal status with some additional but small enhancement due to root planing. Microbiologically, metronidazole dramatically changed the quality of plaque with no supplemental effect when root planing was added.

Adult↗