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Biomedical subjects

J Lindhe

Publications and source records attributed to J Lindhe.

At least 199 records · Page 11Linked to original sources
PubMed1982

Scaling and root planing in shallow pockets.

The present study was undertaken to enable histological assessment of attachment level alterations following repeated scaling and root planing in periodontal sites with "normal" sulcus/pocket depth. Two monkeys (Macaca cynomolgus) were used. During a period of 6 months, scaling was carried out once every 2 weeks at the buccal surfaces of premolars and molars on the right side of the jaws. The contralateral teeth served as untreated controls. Six months after the completion of treatment (1 year after the start of the experiment), the animals were sacrificed and histological sections of all test and control teeth were produced. In these sections the distances between the cemento-enamel junction (CEJ) and the apical extent of the junctional epithelium (JE) and between the JE and the alveolar bone crest (BC) were measured. The results revealed that repeated scaling and planing resulted in an average loss of connective tissue attachment amounting to 0.39 mm and in a corresponding recession of the alveolar bone crest. The findings are discussed in relation to recent observations from clinical trials demonstrating loss of clinical attachment following repeated scaling and root planing in sites with shallow gingival pockets.

Animals↗
PubMed1982

The regenerative potential of the periodontal ligament. An experimental study in the monkey.

The aim of the present study was to examine if new cementum and new attachment may form during healing of a wound prepared in such a way that preference is given to periodontal ligament cells to repopulate the wound area adjacent to a root which has been surgically deprived of its periodontal ligament and cementum layer. The maxillary lateral incisors and mandibular canines in three monkeys were used for experimentation. Following elevation of a mucoperiosteal flap, the buccal and approximal alveolar bone was removed within an area extending from the mid-root level to a level 2 mm apical to the marginal bone crest. Following bone removal, the root surfaces were curetted in order to remove the cementum layer. Notches were prepared in the roots to demarcate the denuded root portion. Prior to repositioning of the tissue flap a millipore filter was placed over the treated area in order to prevent the gingival connective tissue from coming into contact with the root surface during healing. The animals were sacrificed 6 months after surgery. The jaws were removed and histological sections of the experimental teeth and surrounding periodontal tissues were produced. New cementum with inserting collagen fibers was observed on the curetted root surfaces. However, this result of healing did not consistently occur along the entire length of the curetted root portion. In the coronal part of the wound, healing was frequently characterized by connective tissue adhesion to the root surface without signs of cementum formation and fibrous attachment. The results of the experiment suggest that the periodontal ligament cells possess the ability to reestablish connective tissue attachment.

Alveolar Process↗
PubMed1982

New attachment following surgical treatment of human periodontal disease.

The present experiment was undertaken to test the hypothesis that new connective tissue attachment may form on a previously periodontitis involved root surface provided cells originating from the periodontal ligament are enabled to repopulate the root surface during healing. A mandibular incisor with advanced periodontal disease of long standing (the distance between the cemento-enamel junction and the alveolar bone crest was 9 mm) was subjected to periodontal surgery using a technique which during healing prevented the dentogingival epithelium and the gingival connective tissue from reaching contact with the curetted root surface. Preference was hereby given to the periodontal ligament cells to repopulate the previously diseased root surface. After 3 months of healing a block biopsy containing the incisor and surrounding tissue was sampled. The histological analysis revealed that new cementum with inserting principal fibers had formed on the previously diseased root surface. This new attachment extended in coronal direction to a level 5 mm coronal to the alveolar bone crest. This finding suggests that new attachment can be achieved by cells originating from the periodontal ligament and demonstrates that the concept that the periodontitis affected root surface is a major preventive factor for new attachment is invalid.

Connective Tissue↗
PubMed1982

"Critical probing depths" in periodontal therapy.

The present investigation was carried out on 15 individuals who were referred for treatment of moderately advanced periodontal disease. All patients were first subjected to a Baseline examination comprising assessment of oral hygiene and gingival conditions, probing depths and attachment levels. Following case presentation and instructions in oral hygiene measures, the patients were given periodontal treatment utilizing a split mouth design. In one side of the jaw scaling and root planing were performed in conjunction with a modified Widman flap procedure while in the contralateral jaw quadrants the treatment was restricted to scaling and root planing only. The period from initial treatment to 6 months after treatment was considered to be the healing phase and from 6-24 months after treatment the maintenance phase. During the healing phase the patients were recalled for professional tooth cleaning once every 2 weeks. During the maintenance phase the interval between the recall appointments was extended to 3 months. Reexaminations were carried out 6, 12 and 24 months after the completion of active treatment. The results revealed that treatment resulted in loss of clinical attachment in sites with initially shallow pockets, while sites with initially deep pockets gained clinical attachment. With the use of regression analysis "critical probing depths" were calculated for the two methods of treatment used. It was found that the critical probing depth value for scaling and root planing was significantly smaller than the corresponding value for scaling and root planing used in combination with modified Widman flap surgery (2.9 vs 4.2 mm). In addition, the surgical modality of therapy resulted in more attachment loss than the non-surgical approach when used in sites with initially shallow pockets. On the other hand, in sites with initial probing depths above the critical probing depth value more gain of clinical attachment occurred following Widman flap surgery than following scaling and root planing. The data obtained from the reexaminations 12 and 24 months after active treatment demonstrated that the probing depths and the attachment levels obtained following active therapy and healing were maintained more or less unchanged during a maintenance care period which involved careful prophylaxis once every 3 months. However, the data also disclosed that the level of oral hygiene maintained by the patients during healing and maintenance was more critical for the resulting probing depths and attachment levels than the mode of initial therapy used.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1982

Effect of longstanding jiggling on experimental marginal periodontitis in the beagle dog.

The aim of the present experiment was to study the effect of a prolonged period of jiggling force application on the rate of progression of ligature-induced, plaque-associated marginal periodontitis in the beagle dog. The experiment was performed on eight dogs fed a diet which permitted dental plaque accumulation. On Day 0 a phase of periodontal tissue breakdown was initiated around the mandibular fourth premolars (4P; P4) by the placing of plaque retention ligatures around the neck of the teeth. The ligatures were exchanged once a month throughout the entire study. On Day 60 trauma from occlusion of the jiggling type was produced in the P4 region and maintained for 300 days. The animals were sacrificed on Day 360. Following sacrifice tissue sections comprising 1M, 4P, 3P and P3, P4, M1 were produced and subjected to microscopic analysis. The experiment revealed that in the dog jiggling forces applied to teeth which ae also subjected to ligature-induced and plaque-associated marginal periodontitis, may enhance the rate of destruction of the periodontium.

Animals↗
PubMed1982

The effect of elimination of jiggling forces on periodontally exposed teeth in the dog.

The aim of the present investigation in dogs was to analyze the effect on periodontal disease induced by a combination of ligatures and jiggling trauma, when the jiggling forces are eliminated. The experiment was performed in six dogs. On Day 0 a phase of periodontal tissue breakdown was initiated around the mandibular fourth premolars (4P; P4) by placing plaque retention ligatures around the necks of the teeth. The ligatures were changed once a month during a 90-day period. On Day 90 the ligatures were removed. On Day 0 trauma from occlusion (jiggling) was also produced in the 4P and P4 region. On Day 90 the jiggling trauma was removed from the 4P-region (test) while it was maintained in the P4-region (control). Tooth mobility measurements and radiographic examinations were carried out on experimental Days 0, 30, 60, 90, 180, and 360. One dog was sacrificed on Day 90 and the remaining five on day 360. Following sacrifice, tissue sections comprising 1M, 4P, 3P, P3, P4, M1 were obtained and subjected to microscopic analysis. Removal of the jiggling trauma from the test teeth resulted in a markedly decreased tooth mobility, but the loss of connective tissue attachment on Day 360 was similar in the test and control sites. This means that although the control teeth had an increased mobility and a widened periodontal ligament space, the height of the remaining periodontal tissue support was similar in the test and control tooth regions.

Animals↗
PubMed1981

Effect of controlled oral hygiene procedures on caries and periodontal disease in adults. Results after 6 years.

The present report describes the result of a clinical trial in which a group of adults have been maintained on a proper oral hygiene standard over a 6-year period. In 1971--72, 375 individuals were recruited to a test group and 180 to a control group. During the 6 years of trial, 65 persons from the test group and 34 controls were lost. The patients were divided into three age groups; I less than 35 years, II 36--50 years, III greater than 50 years. The members of the test and control groups were first subjected to a Baseline examination which included assessments of oral hygiene, gingivitis, periodontal disease and caries. Following this examination all caries lesions were treated and ill-fitting dental restorations adjusted. Each patient was also given a detailed case presentation and a dental prophylaxis. The control group patients were not involved in any further dental health programs during the subsequent 6-year period. Once a year, however, they were recalled to a public dental health clinic for examination and received symptomatic dental treatment. The test group participants, on the other hand, were given a preventive treatment, repeated once every 2-3 months which included (1) instruction and practice in oral hygiene techniques and (2) meticulous prophylaxis. The patients were re-examined 3 and 6 years after the baseline examination. At the Follow-up examinations the parameters studied at the Baseline examination were recorded again. The findings demonstrated that a preventive program which stimulates individuals to adopt proper oral hygiene habits may resolve gingivitis and prevent progression of periodontal disease and caries. Traditional dental care, on the other hand, did not prevent the progression of caries and periodontitis in adults.

Adult↗
PubMed1981

Effect of oral hygiene instruction and professional toothcleaning on caries and gingivitis in schoolchildren.

The preset study was performed to assess the effect on caries and gingivitis of plaque control measures such as oral hygiene instruction, toothcleaning practice and professional toothcleaning. 104 children, 13-14 years old, participated in the trial. Prior to the start of the preventive treatment all children were examined regarding oral hygiene, gingivitis and caries. The caries examintion was limited to the proximal surfaces of molars and premolars. Following this baseline examination the children were randomly divided into two treatment groups A, and B. Both groups of children were recalled for professional toothcleaning once every 2 weeks during an 18-month period. In each child the professional toothcleaning was restricted to either the right or the left jaws by random selection. In addition, the children of Group A at each recall appointment received careful oral hygiene instruction and practice in proper toothcleaning methods. In conjunction with the professional toothcleaning an abrasive paste was used including fluoride. The children were re-examined 18 months after the baseline examination. The result of the present investigation demonstrated that professional toothcleaning repeated every second and week is a prophylactic measure which in children substantially improves the oral hygiene status, and effectively reduces clinical signs of gingivitis and caries. It was also observed that while oral hygiene instruction and practice in proper toothcleaning techniques reduced plaque and gingivitis, no such effect could be detected regarding the development of caries.

Adolescent↗