Search PubMed⌕ Search

Biomedical subjects

J Lindhe

Publications and source records attributed to J Lindhe.

At least 145 records · Page 8Linked to original sources

Methods of evaluating periodontal disease data in epidemiological research.

The purpose of the present investigation was to examine the use of different methods of data analysis to examine the pattern of periodontal tissue destruction in a group of adults. A clinical examination was carried out on 319 subjects, 20-79 years of age, randomly selected from the population of the city of Ushiku, Japan. The following parameters were studied: missing teeth, plaque, gingivitis, probing pocket depth and probing attachment level. All surfaces of all teeth were examined. The data obtained were evaluated in 3 ways: (i) mean values for each of the clinical parameters were computed for each subject and age group, (ii) the frequency of subjects with one or more sites of attachment loss above certain thresholds was assessed, (iii) percentile plots were generated in such a way that for each age group the percent of sites in subjects with varying attachment levels could be determined. The results revealed that the subjects included in the study had poor oral hygiene, high frequency of gingivitis and loss of probing attachment which increased with age. The mean annual attachment loss for all tooth surfaces was calculated to be less than 0.1 mm. Severe periodontal tissue breakdown was not as common as might have been expected. Hence, the majority of the subjects in the 20-59 year age group had very little evidence of destructive periodontal disease. In these age groups, a comparatively small subfraction accounted for most of the disease detected. After the age of 60, periodontal disease appeared to be more widespread among the subjects examined.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Probing depth, attachment loss and gingival recession. Findings from a clinical examination in Ushiku, Japan.

The present investigation describes probing pocket depth, probing attachment level and recession data from 319 randomly selected subjects, aged 20-79 years, from Ushiku, Japan. The findings are reported as mean values, frequency distributions and percentile plots of the 3 parameters at buccal, interproximal and lingual surfaces of single rooted (incisors, canines, premolars) and molar teeth. Inter-as well as intra-examiner errors for probing pocket depth and probing attachment levels were assessed and found to be small. The data reported revealed that practically all subjects studied had one or more sites in the dentition affected by destructive periodontal disease and that the severity of disease increased with age. It was further observed that in each age group, molars had suffered more attachment loss than single rooted teeth and that the interproximal surfaces as a rule had lost more periodontal tissue support than corresponding buccal and lingual surfaces. The attachment loss difference observed between different surfaces of a given tooth or a group of teeth, however, was comparatively small. In the age groups between 20-59 years, advanced destructive periodontal disease was found in a small subgroup of the subject sample, while after the age of 60 years, widespread destructive periodontitis was common. An attempt was made to examine the progression of destructive disease with age by comparing the frequency distributions of sites with attachment loss of greater than or equal to 3 mm in subjects of different age groups. The data suggested that in younger subject groups, progression was confined to a subset of individuals, while in older age groups, more subjects and sites became involved. A major feature of destructive periodontal disease in older individuals was the accompaniment of attachment loss with recession at the gingival margin. Deep pockets were relatively infrequently detected, while advanced loss of attachment (with recession) occurred at many sites.

Adult↗

Some periodontal tissue reactions to orthodontic tooth movement in monkeys.

The purpose of the experiment reported was to study soft tissue changes at teeth which were orthodontically moved into areas with varying thickness and quality of periodontal tissues. The maxillary central incisors and first premolars in 5 adult monkeys were used as experimental teeth. 6 months prior to the start of the orthodontic treatment phase, the maxillary second premolars were extracted. By surgical means, areas with varying width of the keratinized gingiva were established in the incisor and premolar region. Following a clinical baseline examination which involved assessments of gingival width, location of the gingival margin in relation to cemento-enamel junction and probing attachment level, fixed orthodontic appliances were inserted in order to bodily move the two contral incisors in labial direction through the alveolar bone envelope and the first premolars in distal direction into contact with the first molars. Orthodontic forces were applied for a period of 3-4 months. The lateral incisors and first molars were selected as non-moved control teeth. After the experimental teeth had been retained in their new positions for 1 month, the clinical examination was repeated. Tissue blocks containing test and control specimens were subsequently dissected and prepared for microscopic analysis. The analysis included histometric assessments of loss of connective tissue attachment and height of alveolar bone. The results showed that at every second labially moved incisor, the gingival margin had become displaced in apical direction. The degree of displacement, however, was small and only at 2 teeth accompanied by loss of connective tissue attachment. Throughout the study, these particular teeth also showed obvious signs of gingival inflammation.(ABSTRACT TRUNCATED AT 250 WORDS)

Alveolar Process↗

Efficacy of mouthrinses in inhibiting dental plaque and gingivitis in man.

The aim of the present trial was to determine the effect of different mouthwash preparations used as supplements to regular oral hygiene measures on dental plaque and gingivitis in humans. 96 volunteers were recruited for the study. Following a baseline examination, each subject was given a careful prophylaxis, following which the mouthrinse regimens were initiated. During the 6 weeks of trial, the subjects continued to exercise their regular non-supervised, self-performed plaque control measures. The 96 volunteers were assigned either to 1 or 3 different treatment groups or to a control group according to a randomized code. The members of the control group and the listerine group rinsed with 20 ml of the mouthrinse for 30 s, twice daily, while the members of the chlorhexidine groups (using either a 0.2% or a 0.1% solution) rinsed with 10 ml of the antiseptic solution for 60 s twice daily. Examinations regarding extrinsic stain and plaque were performed at baseline and after 3 and 6 weeks, while the conditions of the gingiva were examined at baseline and after 6 weeks. Extrinsic stain was evaluated using the Lobene index, plaque was assessed by the Turesky modification of Quigley-Hein index and the gingival condition was examined using the gingival index system of Loe & Silness. The results of the trial demonstrated that the 3 active mouthwash preparations used as supplements to regular tooth cleaning measures markedly improved both the oral hygiene status and the gingival conditions of the participating human volunteers, compared to the control rinse.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Prevalence of periodontal disease in young diabetics.

In the present study, the frequency of sites exhibiting gingival inflammation and periodontal tissue breakdown was assessed in one group of 46 individuals (19-25 years old; test group T) who had suffered from diabetes mellitus (Type 1) for 10 years or more, and in another group of 41 non-diabetic controls (18-26 years old; control group C). Each individual was examined regarding oral hygiene status, gingival conditions, probing depths, probing attachment levels and gingival recessions. The interproximal marginal bone level was assessed in bitewing radiographs. No significant differences were found between the 2 groups regarding their oral hygiene status, frequency of sites with probing depths of greater than 3 mm and the position of the interproximal alveolar bone margin. The mean distance between the cemento-enamel junction (CEJ) and the interproximal bone crest was in group T, 0.91 +/- 0.14 (SD) mm and in group C, 0.95 +/- 0.18 (SD) mm. About 80% of the individuals in both groups were free from signs of marginal bone loss and only 1 subject in each group had greater than 6 sites with definitive bone loss. The group of diabetic patients had higher frequencies of inflamed buccal/lingual gingival units, gingival recessions and sites with attachment loss of greater than or equal to 2 mm. Most of the sites (85%) with attachment loss were located at the buccal and lingual surfaces. There were no significant correlations between the periodontal variables and the duration of diabetes, insulin dosage and HbA1 level. Individuals with both retinopathy and nephropathy had significantly more gingival inflammation than diabetic individuals without complications.

Adolescent↗

Guided tissue regeneration in the treatment of furcation defects in man.

The regenerative potential of the periodontal tissues in degree II and III furcation defects at mandibular molars was assessed in a clinical trial using a surgical treatment technique based on the principles of guided tissue regeneration. The patient sample included 37 subjects who had periodontal lesions in the right and left mandibular molar regions, including advanced periodontal destruction within the radicular area. Following a baseline examination, the furcation-involved molars were randomly assigned in each patient to either a test or a control treatment procedure. The test procedure included the elevation of mucoperiosteal flaps and the placement of a teflon membrane to cover the entrance of the furcation area and the adjacent root surfaces as well as a portion of the alveolar bone apical to the crest. The flaps were repositioned and secured with interdental sutures. A procedure identical to the one used at the test teeth was performed at the control tooth regions with the exception of the placement of the teflon membrane. Following surgery, all patients were placed on a plaque control regimen which involved daily rinsing with chlorexidine gluconate and, in addition, professional tooth cleaning once every 2 weeks for 6 months. After 6 months of healing, the test and control sites were re-examined. The findings demonstrated that the treatment of degree II furcation defects at mandibular molars using the principles of guided tissue regeneration in 19 sites out of 21 resulted in the resolution of the furcation defect. Conventional therapy reached the same goal in less than 20% of the cases treated.(ABSTRACT TRUNCATED AT 250 WORDS)

Connective Tissue↗

Lack of bacterial invasion in experimental periodontitis.

The present study in the beagle dog was performed to analyze whether micro-organisms from a subgingival microbiota could be translocated into or had the potential to invade the pocket epithelium and the gingival connective tissue during a phase of rapid breakdown of the attachment apparatus. An attempt was also made to assess whether tetracycline therapy suppressed the subgingival microbiota and changed the size and quality of the lesions in the gingival tissue. 5 inbred beagle dogs were used. Throughout the period of experimentation, the animals were fed a soft diet permitting gross accumulation of plaque and calculus. No mechanical plaque control measures were performed during the course of the study. On day 0, a 120-day period of periodontal tissue breakdown was initiated at the right mandibular 3rd and 4th premolars by tying cotton floss ligatures around the neck of these teeth. The process of tissue breakdown at the mandibular left 3rd and 4th premolars was started 30 days later. The ligatures were replaced once every 2 weeks during the subsequent 4-month period. On experimental day 120, the first biopsy was performed and gingival tissue sections prepared for light and electron microscopic assessment of a series of histometric characteristics. On day 120, a 30-day period of tetracycline (per os) administration was initiated. Each dog was given a dose of 500 mg tetracycline twice daily. On day 150, the biopsy procedure was repeated in the mandibular left premolar regions.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Marginal tissue reactions at osseointegrated titanium fixtures (I). A 3-year longitudinal prospective study.

16 consecutive totally edentulous patients were provided with 95 osseointegrated titanium fixtures in 7 upper and 9 lower jaws. Facultatively removable bridges were later connected to abutments, attached to the fixtures. The marginal soft and hard tissue reactions were investigated at a baseline examination and after 6, 12, 21, 30 and 39 months by standardized clinical and radiographical methods. At the last examination, microbiological samples and gingival biopsies were also analysed. The % ratios of abutments without plaque, 70-75%, and without any gingivitis, 80-85%, were almost constant throughout the study. The mean probing depth was 2.9 mm at the final examination. About 75% of all probing depths were 3 mm or less and none exceeded 5 mm. The bridge-gingiva distances increased during the investigation. Attached gingiva surrounded 65% of the buccal and lingual abutment surfaces. Only 0.9 mm marginal bone was lost as a mean during the first year and not more than 0.05 mm annually for the next 2 years. After 6 months, no significant changes in marginal bone levels occurred. The perifixtural bone gradually became more radiopaque, especially marginally in upper jaws, indicating a successive load-related remodelling. The microbiotia comprised coccoid cells and non-motile rods to 93% in 32 samples. Healthy tissues were present in 35% of the 14 soft tissue biopsies. In a further 29%, only a slight inflammation was observed. No constant correlations could be established for any of the investigation parameters used. It is concluded that the marginal soft tissue reactions were mild and not significant for a progressive periodontitis. Mobility tests of separate fixtures combined with quantitative and qualitative standardized radiological examinations of the surrounding bone appear to provide a truer comprehension of longitudinal events at osseointegrated implants than conventional clinical soft tissue observations. The prognosis for the osseointegrated implants appears excellent, especially with regard to the microbiotia, the small marginal bone height changes, and the radiological indications of remodelling in the perifixtural bone.

Adult↗

Marginal tissue reactions at osseointegrated titanium fixtures. (II) A cross-sectional retrospective study.

20 totally edentulous patients, provided with 24 facultatively removable fixed bridges (13 upper and 11 lower jaws) were recalled. The material consisted of 125 osseointegrated titanium fixtures with a mean observation time of 7.6 years (range 6 months to 15 years). The marginal tissues were examined by conventional periodontal clinical methods and standardised radiography. Microbiological samples and biopsies of the soft marginal barrier tissues were retrieved for dark-field and histological analysis, respectively. The percental ratios of abutment surfaces devoid of plaque and without signs of gingivitis, were 46% and 20%, respectively. In contrast to earlier studies, the presence of plaque and gingivitis was significantly correlated. This relationship was probably due to more plaque being present. The mean probing depth was 3.8 mm. In 40% of the measurements, the probing depths were 3 mm or less, and in 45% between 4 and 5 mm, whereas they only in 15% were 6 mm or more. They were greater in upper than in lower jaws and were found to be significantly correlated with gingivitis. Attached gingiva surrounded about 51% of the buccal and lingual abutment surfaces. The marginal bone height changes were very small during the follow-up period (0.07 mm annually). Coccoid cells and non-motile rods dominated the microflora to 94% in the 48 samples taken. Out of the 19 biopsies, 58% showed healthy mucosa and a further 37% had the lowest inflammation score. The indications of gingivitis and deep pockets at the clinical examination were not found accompanied by an accelerated marginal bone loss, nor by a microflora or histological changes indicative of periodontitis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

New attachment formation in the human periodontium by guided tissue regeneration. Case reports.

The aim of the present study was to evaluate whether a regenerative surgical procedure, based on guided tissue regeneration, could predictably result in the formation of a new attachment in human teeth. The material included 12 teeth in 10 patients with advanced periodontal disease. Following flap elevation, scaling, root planing and removal of granulation tissue, a teflon membrane was placed over the denuded root surface in such a way that the epithelium and the gingival connective tissue were prevented from reaching contact with the root during healing. The flap was replaced on the outer surface of the membrane and secured with interdental sutures. This design of wound preparation gives preference to the cells originating from the periodontal ligament (PDL-cells) to repopulate the wound area adjacent to the root. Histologic analysis of the result of treatment was made in 5 of the 12 teeth scheduled for extraction. In the remaining 7 teeth, the result was evaluated using clinical measurements. The result of healing disclosed that in all teeth treated, substantial amounts of new attachment had formed. This suggests that predictable restitution of the attachment apparatus can be accomplished by using a method of treatment which is based on the principle of guided tissue regeneration.

Adult↗

Treatment of localized gingival recessions with coronally displaced flaps and citric acid. An experimental study in the dog.

The present study was designed to examine the effect of citric acid conditioning on the result of healing following treatment of localized gingival recessions with coronally displaced flaps. In 3 beagle dogs, localized gingival recessions were surgically created at the buccal surfaces of canines, premolars and molars. All experimental sites were allowed to accumulate plaque for a period of 6 months. Following preparation of notches in the buccal root surfaces at the level of the gingival margin, buccal and lingual mucoperiosteal flaps were raised. The exposed portion of the root surfaces was scaled and the cementum layer was removed. Another notch was prepared in the root surfaces at the level of the crest of the alveolar bone. Half the number of the roots were treated by topical application of citric acid while the remaining roots were used as non-acid treated controls. The flaps were sutured in a coronally displaced position. After 3 months of healing, the dogs were sacrificed and the jaws removed and placed in fixative. After decalcification, histological sections of the experimental roots and their periodontal tissues were produced. The 2 notches described above were used as reference points in the histological examination. The histological analysis disclosed that new attachment had formed on all test and control roots and extended in some specimens of both groups to a position coronal to the presurgical level of the gingival margin. The amount of new attachment was similar in the 2 categories of roots, demonstrating that citric acid conditioning did not produce additional new attachment.

Animals↗

The effect of mouthrinses on parameters characterizing human periodontal disease.

The objective of the present clinical trial was to assess the efficacy of mouthwashes containing antiseptic agents on established and developing plaque and periodontal disease in adult subjects using a newly described clinical research model. The study was carried out in 21 patients with periodontal disease. At the baseline examination, all tooth surfaces-sites were studied with regard to dental plaque, gingivitis, bleeding on probing to the base of the pocket and probing pocket depths. The patients were subsequently randomly assigned to 1 of 3 groups, each consisting of 7 individuals. Group A rinsed with a 0.01% solution of Sanguinarine, group B rinsed with a 0.2% solution of chlorhexidine and group C rinsed with a placebo solution. No instructions regarding mechanical plaque control measures or information regarding the etiology and pathogenesis of periodontal disease were given to any of the patients during the course of the 6-weeks of trial. The clinical examination was repeated after 2 weeks use of the mouthwash preparations. Following the re-examination, all patients were subjected to scaling and root planing in 2 jaw quadrants chosen at random. After another 2 weeks, the 2nd re-examination was performed and the teeth in the 2 remaining jaw quadrants were thoroughly scaled. The final examination was performed 2 weeks later. During the 4 weeks of rinsing, without adjunctive professional mechanical debridement, the frequency distribution of plaque Index scores 2 + 3 did not change in the group of patients using the placebo solution, but was significantly reduced in both the chlorhexidine and the Sanguinarine groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

The significance of coronal growth of periodontal ligament tissue for new attachment formation.

The present study was designed to examine whether coronal growth of granulation tissue originating from the periodontal ligament is a prerequisite for new attachment formation. In each of 4 monkeys, 1 central incisor and 2 first molars in the maxilla and the mandible were selected for experimentation. Angular bony defects were surgically produced to the mid-root level around each single root after crown resection and root separation of the multirooted teeth. The periodontal ligament tissue and the root cementum were removed to the bottom of the bony defects. In half the number of the teeth, an elastic ligature was placed tightly around each root at the bottom of the defects (test roots). In the remaining teeth, an elastic ligature was placed loosely around each root at the same level (control roots). All roots were subsequently covered by laterally displaced flaps. After 3 months of healing, the animals were sacrificed and the jaws removed and placed in fixative. Following decalcification, histological sections of the experimental roots and their surrounding periodontal tissues were produced. The histological analysis disclosed that new attachment had former to a level coronal to the elastic ligature in 10 of 14 control roots but in only 1 of 18 test roots. The results indicate that the repopulation of a detached root surface by cells from the periodontal ligament is a prerequisite for new attachment formation.

Animals↗

Design of clinical trials of traditional therapies of periodontitis.

The present paper on the design of clinical trials of periodontal therapy first addresses the issue of the etiology of periodontal disease. It is suggested that most if not all forms of destructive periodontal disease are caused by microorganisms and that there are different forms of disease with different microbial etiologies. The progressive nature of destructive periodontal disease is subsequently discussed and it is emphasized that, in a given patient, periodontal sites which show signs of inflammation and attachment loss may not over a period of several months and years show further sign of attachment loss. The present methods of assessing periodontal disease do not allow us to discriminate between potentially active and inactive sites in untreated patients. The significance and variability of indicators of periodontal disease such as bleeding on probing, probing pocket depth and probing attachment level measurements are discussed. The errors inherent in the various measurements are analyzed and suggestions are presented describing how alterations in any of the above parameters could be identified and presented in a clinical trial. Of concern for the statistical analysis of clinical data of periodontal disease is the definition of the "experimental unit". For a number of years, the "experimental unit" in periodontal trials was the patient. It is clear, however, that different sites within the same individual show different patterns of disease progression and lesion morphology and often respond differently to periodontal therapy. Statistical analyses must consequently be designed which recognize differences in site-to-site infection and lesion morphology within a common host. Until such analyses are available, the investigator should be wary of pooling data within the same individual, since such pooling may obscure meaningful alternatives which may take place in individual periodontal sites. Some goals of periodontal therapy are subsequently identified. 4 goals are discussed more in detail, namely: to establish conditions which will allow the patient to maintain a dentition without further breakdown of the periodontium; to reduce pocket depth to establish an anatomy in the dentogingival region which with proper maintainance care will prevent the re-establishment of the subgingival infection; to gain attachment as a result of treatment; to assess the effect of a certain chemotherapeutic agent on periodontal disease.

Clinical Trials as Topic↗