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Biomedical subjects

J Lindhe

Publications and source records attributed to J Lindhe.

At least 127 records · Page 7Linked to original sources
PubMed1992

Probing pocket depth at mobile/nonmobile teeth.

The aim of the present investigation was to study the influence of an increased tooth mobility on the resistance offered by the periodontal tissues to probing. 6 beagle dogs were used. At the start of the experiment, the animals had clean teeth and normal gingival and periodontal conditions. In each dog, a device was installed in the lower left jaw quadrant to expose the third premolar (P3) to jiggling forces which would enhance the mobility of this "test" tooth. The contralateral tooth served as the non-jiggled control. During the 3 months of experimentation, the teeth of the dogs were cleaned on a regular basis. Clinical examinations including tooth mobility measurements were performed on days 0 and 90. After the examination on Day 90, a probe was inserted in the buccal "pocket" of the mesial root of 3P and P3. The probe was retained with composite. Biopsies including the test or control tooth with adjacent buccal periodontal tissues were harvested, fixed and decalcified. Each biopsy was divided in one mesial and one distal portion (root). The distal portion was embedded in Epon, sectioned and stained in PAS and toluidine blue, while the mesial portion, following probe removal was embedded in paraffin, sectioned and stained in hematoxylin-eosin. The sections were exposed to histometric and morphometric measurements. The findings demonstrated that tissue alterations which occur at mobile teeth may reduce the resistance offered by the periodontal tissues to clinical probing. Such alterations include (i) reduced height of the alveolar bone, (ii) reduced amount of collagen, and increased vascularity in the enlarged supracrestal connective tissue.

Animals↗
PubMed1992

The effect of supragingival plaque control on the subgingival microbiota in subjects with periodontal disease.

The present investigation was performed to study the effect on the subgingival microbiota, of a plaque control program which included meticulous oral hygiene instruction, supragingival scaling and professional monitoring during a 2 year period. 300 subjects were examined for periodontal disease and monitored for 2 years without treatment. After the 2 year examination, 80 subjects were invited to participate in a treatment program intended to improve the standard of their self-performed plaque control. 40 of the invitees had a gingivitis and only minor attachment loss, while 40 subjects had moderate signs of periodontitis. 62 subjects volunteered for this treatment. 23 of the volunteers (Group AB) had several sites with deep pockets (> 4 mm). 39 of the volunteers had gingivitis but shallow pockets only (Group C). Group AB contributed 31 shallow pocket sites (A-sites) and 40 deep pocket sites (B-sites), while Group C contributed 63 shallow sites (C-sites). After the clinical examination, samples of the subgingival microbiota were harvested from the 134 A, B and C sites. The 62 subjects were enrolled in a supervised oral hygiene program. Supragingival scaling was carried out. Oral hygiene instruction was provided and repeated on an individual need basis so that all subjects reached and maintained a supragingival plaque score which was < 20%. 24 months after the year 2 examination, the 62 subjects were examined again using both clinical and microbiological examination procedures. The findings demonstrated that carefully performed supragingival plaque control changed the quantity and the composition of the supragingival microbiota.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Considerations on the contribution of ageing to loss of periodontal tissue support.

The present study is an attempt to assess if age-related changes, manifested as loss of probing attachment and alveolar bone, occur in humans. 511 subjects, in ages 20-24, 30-34, 40-44, 50-54 and 60-64 years, were included in the study. All subjects had undergone a comprehensive clinical examination, including recordings of probing pocket depth and probing attachment level. A subsample of subjects was selected, whose periodontal status indicated minimal experience of destructive periodontal disease. In these particular subjects, the height of the alveolar bone was also assessed. The results showed that in the subsample, (i) attachment loss increased with age, but (ii) a high proportion of tooth surfaces remained with no attachment or alveolar bone loss in ages between 20 and 64 years. There are reasons to suggest, therefore, that age-related alterations in the periodontium may not inevitably be manifested as loss of probing attachment or alveolar bone.

Adult↗
PubMed1991

Clinical and structural characteristics of periodontal tissues in young and old dogs.

The aim of this study was to examine some clinical and structural features of healthy periodontal tissues in young and old beagle dogs. The material consisted of 10 beagle dogs; group I (1-year old) and group II (8-9 years of age). All animals belonged to the same beagle dog colony and had been carefully monitored from birth. A given day was termed day 0 on which the teeth of all 10 dogs were scaled and polished and a 6-week period of enhanced plaque control was initiated. On day 42, clinical examinations were performed and biopsies obtained from the right mandibular 4th (4P) and 3rd (3P) premolar regions. The biopsies were prepared for histometric and morphometric analyses. Clinically, the lower premolars of the old but not the young dogs showed signs of marked wear. In the old dogs, the free gingival unit had a more curved and bulky appearance than in the young animals and in the old dogs, the free gingiva was consistently separated from the attached gingiva by a gingival groove. The histometrical dimensions of the free marginal gingiva and the width of the coronal portion of the periodontal ligament did not differ between the 2 groups of dogs. The apical cells of the junctional epithelium (aJE) in the young dogs were consistently located at the cemento-enamel junction (CEJ), whereas in the old dogs, aJE was consistently located apical to the CEJ.(ABSTRACT TRUNCATED AT 250 WORDS)

Aging↗
PubMed1991

Periodontal tissue reactions to orthodontic extrusion. An experimental study in the dog.

Orthodontic tooth extrusion is used at crown lengthening procedures or in conjunction with periodontal therapy aimed at eliminating or reducing angular bone defects. A technique for orthodontic extrusion combined with resection of the supracrestal attachment fibers (fiberotomy) was recently proposed as an adjunct to certain restorative procedures. The aim of the present investigation was to analyze reactions of the periodontal tissues to orthodontic extrusion when combined with fiberotomy. In 5 beagle dogs, the mesial roots of the 2nd, 3rd and 4th hemisected mandibular premolar were used as target roots while the distal roots served as reference units. After a baseline examination, an orthodontic extrusion device (stent) was installed and reactivated at 2-week intervals during an 8-week period of active tooth movement. Immediately following the installation of the stent and once every 2nd week, the target roots were exposed to fiberotomy. After the active period, the teeth were retained in their new position for a period of 8 weeks. Clinical, radiographical and histological measurements were performed. The results from the investigation demonstrated that orthodontic extrusion combined with supracrestal fiberotomy resulted in a coronal displacement of the tooth and was associated with pronounced recession of the gingival margin and extensive loss of connective tissue attachment. The degree of gingival recession and the amount of loss of connective tissue attachment were, however, less extensive than the amount of tooth extrusion. Thus, repeated fiberotomy obviously failed to entirely prevent coronal migration of the attachment apparatus. It was also observed that undesired attachment loss had occurred at the reference roots.

Animals↗
PubMed1991

Periodontal characteristics in individuals with varying form of the upper central incisors.

It has been suggested that the variation in the morphology of the human periodontium may be related to the shape and form of the teeth. Furthermore, the severity of symptoms of periodontal disease have been proposed to differ among these various morphologic entities or "biotypes". The aim of the present study was (i) to identify individuals with markedly different crown forms and (ii) to determine probing pocket depth, probing attachment level and amount of gingival recession that had occurred at different teeth and tooth surfaces in such individuals. Clinical photographs of the maxillary incisor tooth region of 113 subjects who had been recruited for a long-term study on periodontal disease were available. The length (CL) and width (CW) of the crowns were determined and the CW/CL ratio was calculated for each tooth. 10% in each tail, 11 subjects in each group, were arbitrarily chosen as having either a long-narrow (N) or a short-wide (W) form of the central incisors. The probing pocket depth, probing attachment level and gingival recession data available from all subjects and subjects in groups W and N were compared and analyzed using the Student t-test and multiple regression analysis. The result from the analyses demonstrated that: (1) subjects with a long-narrow form of the upper central incisors had experienced more recession of the gingival margin at buccal surfaces than subjects who had a short-wide tooth form; (2) there was a significant influence of the CW/CL-ratio on the probing attachment level (p less than 0.05) and the amount of gingival recession (p less than 0.01) on buccal tooth surfaces.(ABSTRACT TRUNCATED AT 250 WORDS)

Bicuspid↗
PubMed1991

On the prevention of caries and periodontal disease. Results of a 15-year longitudinal study in adults.

In 1971-72, a total of 375 adult subjects were recruited for a clinical trial aimed at assessing the effect of a preventive program, based on plaque control and topical application of fluoride, on the incidence of caries and periodontal disease. After a baseline examination, the volunteers were subjected to scaling, root planning and conventional caries therapy. During the course of the subsequent 6 years, they were recalled for preventive measures once every 2-3 months. After the 6-year follow-up examination, however, it was decided to extend the interval between the preventive sessions. Thus, during the next 9-year period, about 95% of the participants returned for preventive measures only 1 to 2 times per year. A small subgroup of about 15 subjects, who, during the initial 6 years had developed new caries lesions or had exhibited additional periodontal attachment loss, however, were also during the following 9 years recalled 3-6 times per year for oral hygiene control and preventive therapy. The re-examination performed in 1987 disclosed that the 317 subjects, who participated during the entire 15-year period, had a low incidence of caries and almost no further loss of periodontal tissue support. It was suggested that improved self performed oral hygiene, daily use of fluoridated dentifrice and regularly repeated professional tooth cleaning effectively prevented recurrence of dental disease.

Adult↗
PubMed1991

Clinical risk indicators for periodontal attachment loss.

The purpose of the present investigation was to evaluate the association of baseline clinical parameters of periodontal disease with disease progression in the following year. 271 randomly selected subjects from Ushiku Japan were monitored for overt gingivitis and plaque accumulation at 4 sites per tooth and probing pocket depth, probing attachment level and bleeding on probing at 6 sites per tooth for all teeth at baseline and 1 year. A subject was considered to exhibit additional attachment loss if one or more sites increased 3 mm or more in a probing attachment level measurement in one year. The clinical variables included age, sex, number of missing teeth, mean pocket depth and attachment level. In addition, the % of sites which exhibited overt gingivitis, visible plaque, pocket depths, attachment levels or gingival recession over certain mm thresholds or bled on probing were determined. Chi 2 analysis was used to seek significant associations between the baseline clinical variables and subsequent attachment loss in a subject. Only 74 of the 271 subjects (27.3%) exhibited additional attachment loss of 3 mm or more at 1 or more sites after 1 year. Older subjects had a greater risk of disease progression than younger subjects. There were no significant differences in % of individuals exhibiting additional attachment loss when divided on the basis of sex, number of missing teeth or % of sites with overt gingivitis. However, the greater the % of sites with visible plaque or which bled on probing, the greater was the likelihood of subsequent attachment loss. Increasing mean levels of pocket depth or attachment level or increasing %s of sites exhibiting prior attachment loss were strongly related to the proportion of individuals with subsequent attachment loss. Gingival recession exhibited similar but weaker relationships. Log-linear analysis suggested that the association between bleeding on probing, age, or plaque levels with additional attachment loss may be explained by the association of these variables with baseline attachment loss. The analyses were repeated with a positive subject defined as having only 1 active site or 2 or more active sites. 37 subjects fit the 1st criterion and the remaining 37 the 2nd criterion. The associations observed were almost identical to those found when subjects were considered positive on the basis of 1 or more changing sites. Discriminant analysis was used to classify subjects as active or inactive using up to 11 predictor variables.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1991

The effect of an anticalculus dentifrice on calculus formation and gingival recession in Thai children and teenagers: one-year study. Study #1. An anticalculus dentifrice containing 3.3% soluble pyrophosphate and 1.0% of a copolymer.

A one-year, double-blind clinical study was conducted on a population of Thai children and teenagers to determine the effect of the twice daily use of an anticalculus dentifrice on supragingival calculus formation and gingival recession, as compared to the use of a placebo dentifrice and the continuation of customary oral hygiene procedures. The subjects were initially evaluated for calculus using the Volpe-Manhold procedure and for gingival recession using the GRT procedure of Volpe, Triratana, and Rustogi. All subjects received an oral prophylaxis and were assigned to the use of 1) a placebo dentifrice containing 0.243% sodium fluoride in a silica base, 2) an anticalculus dentifrice containing 3.3% soluble pyrophosphate and 1.0% Gantrez copolymer--in a 0.243% sodium fluoride/silica base, or 3) continuation of customary oral hygiene procedures. After one year, the subjects using the anticalculus dentifrice had 37.01% less supragingival calculus and 25.09% less gingival recession than the subjects using the placebo dentifrice. Additionally, after one year, the subjects using the anticalculus dentifrice had 34.86% less supragingival calculus and 29.95% less gingival recession than the subjects who continued their customary oral hygiene procedures. All reductions were statistically significant at the 95% or greater level of confidence.

Adolescent↗
PubMed1991

The association between supragingival [correction of subgingival] calculus deposits and the extent of gingival recession in a sample of Thai children and teenagers.

A survey was performed on a sample of children and teenagers in Thailand. The sample consisted of 260 subjects ages 10-17 years. Assessments of the prevalence and amount of supragingival calculus (Volpe-Manhold) on the facial and lingual surfaces of the six mandibular anterior teeth were recorded. All subjects then received a thorough whole mouth prophylaxis. Two weeks later they were reexamined for gingival recession using the Gingival Recession Total (GRT) scoring system on the same six mandibular anterior teeth. For the analysis, the calculus scores were used to categorize the subjects as having slight, medium, or heavy calculus. Using the GRT scores, the same subjects were then categorized as having mild, moderate or extensive gingival recession. The categories of both calculus level and gingival recession level were statistically assessed using the Chi-square distribution and a significant difference was found indicating that the amount of calculus was related to total gingival recession. Subjects with slight calculus had more mild recession whereas medium or heavy calculus formers had more moderate or extensive total gingival recession scores.

Adolescent↗
PubMed1990

Some anatomical features of the periodontium of the deciduous and permanent dentition in the beagle dog.

The present study describes some anatomical characteristics of teeth and periodontal tissues in the deciduous and permanent dentition of the beagle dog. Five animals were used. At the age of 10 weeks (Period A) and 15 months (Period B), respectively, a plaque control period was initiated. At the end of each plaque control period, clinical examinations were performed. Biopsies were obtained from the 02P, 03P (Period A) and P3, P4 (Period B) tooth regions and were examined with the light microscope. Histometric and morphometric measurements were made. The macroscopic and microscopic measurements revealed that marked differences exist between the teeth and the periodontium of the deciduous and the permanent dentition. The permanent premolar erupting into the position of the deciduous premolar was found to be significantly wider and higher than its precursor. Also the shape of the crown of the permanent premolar differed from that of the deciduous premolar. The sinuous contour of the buccal gingival margin was more accentuated in the deciduous than in the permanent dentition. The free gingiva was shorter and the periodontal ligament space was wider in the deciduous than in the permanent dentition. The free gingival unit in the deciduous dentition consisted of a larger volume of epithelium and a smaller volume of connective tissue than the corresponding unit in the permanent dentition. The connective tissue of the deciduous gingiva contained a larger proportion of fibroblasts and a lower proportion of collagen fibres than the corresponding tissue of the permanent gingiva.

Animals↗
PubMed1989

Longitudinal changes in periodontal disease in untreated subjects.

About 300 subjects, 20-79 years of age were recruited for a longitudinal study on the effect of periodontal therapy. The result of a baseline examination have been reported earlier. Following this baseline examination, the subjects were monitored for 24 months without therapy. Re-examinations were performed after 12 and 24 months. All teeth including the 3rd molars were included in the examinations. Presence of plaque was assessed at 4 surfaces per tooth and gingivitis, probing pocket depth, probing attachment levels were assessed at 6 locations per tooth. Out of the subject sample examined at baseline, 57 individuals failed to return for either the 1st, the 2nd or both re-examinations. An analysis was performed regarding the periodontal status at baseline, of the respondents and non-respondents. The results from the follow-up examinations of the participating 20 to 79 year-old subjects revealed that the sample underwent, during a 2-year period, only minor changes with respect to a series of different parameters characteristic of periodontal disease. Thus, the mean values of probing pocket depth and probing attachment level failed to change between baseline and the re-examinations after 1 and 2 years. Even if the mean values underwent only minor changes, however, certain subjects within each age category improved their periodontal conditions, whereas other subjects worsened. Furthermore, the findings of the re-examinations revealed that there was a strong correlation between improving plaque levels and gingivitis. The relationship between supragingival plaque levels and changes with respect to probing depth and attachment levels were weak.

Adult↗
PubMed1989

Periodontal loser sites in untreated adult subjects.

Subjects in age groups between 20 and 79 years were recruited for a study on the effect of different modalities of periodontal therapy. A baseline examination included assessments of plaque, gingivitis, probing pocket depth and probing attachment level. The subjects received no periodontal therapy for 2 years but were recalled for re-examination after 1 and 2 years. The results from the baseline examination and the overall changes which occurred in the sample during the 2 years have been reported previously. The present study describes some characteristics of subjects and sites that lost probing attachment of 3 mm or more during the course of the 24 months of monitoring. 161 of the 265 subjects who returned for both re-examinations had no change of the attachment level at any site that amounted to 3 mm or more. Of the 104 subjects that showed deterioration, at or above this level, the majority exhibited disease activity either during the 1st or the 2nd year of monitoring. Only 20 subjects showed disease activity during both year 1 and year 2. In addition, 70% of the sites that deteriorated (loser sites) occurred in 12% of the subjects. Loser sites were most frequently detected in older subjects and at molar sites. Most of the loser sites occurred at interproximal surfaces and were most numerous at surfaces with initially advanced loss of attachment.

Adult↗
PubMed1989

Guided tissue regeneration in the treatment of furcation defects in mandibular molars. A clinical study of degree III involvements.

The present investigation was designed to evaluate the regenerative potential of the periodontal tissues in degree III furcation defects at mandibular molars using a treatment procedure based on the principle of guided tissue regeneration. The patient sample included 21 patients, 26-65 years of age, who presented periodontal lesions in the right and left molar regions including "through and through" furcation defects. After an initial examination, each patient was subjected to a series of full-mouth scaling and root planing. 2-3 months later, they were recalled for 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 muco-periosteal flaps at the buccal and lingual aspects of the molars. Granulation tissue was removed and the exposed root surfaces were debrided and planed. The width and the height of the entrance openings to the furcation defects were assessed. A teflon membrane was adjusted to cover the entrances to the defects (buccal and lingual) and was retained in the manner described by Pontoriero et al. (1988). The flaps were repositioned on the outer surface of the membrane and secured by sutures which were removed after 10 days. Following surgery, the patients were instructed to rinse the mouth twice daily for 4 weeks with chlorhexidine gluconate. The membranes were removed after a healing period of 1-2 months. A surgical procedure identical to the test procedure was performed in the control tooth regions with the exception of the placement of membranes.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

Gingivitis in the deciduous and permanent dentition. An experimental study in the dog.

The present investigation was performed in order to study the reaction of the gingiva in the deciduous and permanent dentition of dogs to 3 weeks of plaque accumulation. The study was carried out in 10 beagles, divided into 2 groups of 5 dogs each; group I and group II. When the dogs of group I were 10 weeks old, a meticulous plaque control regimen was initiated in order to establish clinically healthy gingiva. After 6 weeks of plaque control, the gingivae of the lower deciduous molars was exposed to a clinical examination, and biopsies as well as bacterial plaque samples were harvested from tooth 03P and 02P. A second plaque control regimen was initiated when the same dogs were 15 months old. After 6 weeks of plaque control, the gingiva of the permanent dentition was examined and biopsies sampled from tooth P3 and P4. In the dogs of group II, plaque control regimens of 3 weeks duration were initiated when the animals were 10 weeks and 15 months old. Clinical examinations were performed at the end of each 3-week period. Immediately after the clinical examinations. 3-week periods of plaque accumulation were initiated. Examinations and plaque sampling were performed after each of these 3-week periods and biopsies were sampled from the deciduous and permanent dentition as described for group I. The biopsies were processed for histometric and morphometric measurements. The findings from the experiment showed that careful plaque control resulted in the establishment of clinically healthy gingiva. In both the deciduous and permanent dentition, however, a clinically healthy gingiva was found to contain a small inflammatory cell infiltrate (ICT). 3 weeks of plaque accumulation resulted in both dentitions in the development of clinical signs of gingivitis and in the formation of comparatively large ICT. The large ICT of the permanent gingiva resided in the coronal portion of the free gingival unit, while in the deciduous dentition, the inflammatory lesion occupied a narrow tissue portion along the entire border of the dento-gingival epithelium. The ICT of the permanent gingiva harbored a larger portion of plasma cells than the inflammatory lesion studied in the deciduous dentition.

Animals↗
PubMed1988

The angular bony defect in the maintenance of the periodontal patient.

The present retrospective study was performed to evaluate some long-term alterations of the alveolar bone level at periodontal sites with angular and even ("horizontal") patterns of bone loss. The investigation included 48 patients who, following treatment for advanced periodontal disease, were placed in a maintenance care program which included recall appointments every 3-6 months for a period of 5 to 16 years. The material of the study comprised all teeth at which angular osseous defects (test sites) could be detected in a full-mouth series of radiographs obtained at the end of the active treatment phase. Alterations in the position of the marginal alveolar bone crest and the base of the osseous defect which took place during the maintenance period were assessed by comparing the post-treatment radiographs with a 2nd set of radiographs obtained at the final examination. In the same patients, an equal number of contralateral or neighboring teeth at which bone loss in the radiographs had an even or "horizontal" character were included as controls. The results from the assessments demonstrated that periodontal sites which, following active therapy displayed either angular or "horizontal" patterns of alveolar bone loss underwent, during a 5-16 year period of maintenance, only minor bone level alterations. Additional loss of supporting bone occurred equally frequently at sites with "horizontal" and angular patterns of bone loss. Thus, the findings reported failed to show up sites with angular bony defects as being particularly susceptible to recurrent destructive periodontitis.

Adult↗
PubMed1988

Guided tissue regeneration in degree II furcation-involved mandibular molars. A clinical study.

The present clinical trial was designed to evaluate the regenerative potential of the periodontal tissues in degree II furcation defects at mandibular molars using a surgical treatment technique based on the principles of guided tissue regeneration. The patient sample included 21 subjects, 22-65 years of age. The patients selected had periodontal lesions in the right and left molar regions including advanced periodontal tissue destruction within the interradicular area. After an initial examination, each patient received a series of full-mouth scalings and root planings. 2-3 months later, they were recalled for a baseline examination including assessment of plaque, gingivitis, probing depths and probing attachment levels. 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 at the buccal and lingual aspect of the alveolar process. The inner surface of each flap was carefully curetted to remove epithelium and granulation tissue. The root surfaces were scaled and planed. A teflon membrane was adjusted 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 placed on the outer surface of the membrane and secured with interdental sutures which were removed after 10 days of healing. Following surgery, the patients were instructed to rinse the mouth twice daily with chlorhexidine gluconate. A second surgical procedure was performed after a healing period of 1-2 months to remove the teflon membrane.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗