A long-term survey of tooth loss in 600 treated periodontal patients

Pathogenesis of periodontitis

Periodontitis is an inflammatory disease of the periodontium which is characterized by a progressive destruction of the tissues supporting the tooth. Its primary etiology is an ill-defined series of microbial infections which may be composed of only some of the more than 300 species of bacteria currently recognized in the oral cavity. The disease is currently considered to progress as periodic, relatively short episodes of rapid tissue destruction followed by some repair, and prolonged intervening periods of disease remission. Despite the apparent random distribution of episodes of disease activity, the resulting tissue breakdown exhibits a symmetrical pattern of alveolar bone loss and pocket formation which is common to several forms of periodontitis, although the distribution of the most affected teeth and surfaces may vary among diseases (e.g., juvenile periodontitis versus adult periodontitis or rapidly progressive periodontitis). Several reports have indicated that bacterial cells can be found in the pocket wall of periodontitis lesions. The translocation of bacteria into the tissues from the pocket environment is quite common, as evidenced by the common occurrence of bacteremias in patients with periodontitis following relatively minor events such as chewing and oral hygiene procedures. However, it is important to distinguish between the passive introduction of bacteria into periodontal tissues and frank invasion as might occur in an acute infection, since the pathological implications may be quite different.

A perspective on periodontal diagnosis

Periodontal diseases are best considered as the outcome of an imperfect host-parasite interaction. In most cases, diagnosis involves labelling certain clinical manifestations without a complete understanding of the causes of the disease. Therefore, treatment based on the "diagnosis" is not necessarily logical or effective. As the causes which underly the disease become more evident, the underlying mechanisms of disease can be used to refine our diagnostic methods. For example, deficiencies in host defenses, or the presence or increased proportions of certain bacterial pathogens may be indicative of imbalances in the normal host-parasite equilibrium. For a laboratory test to be reliably applied to the diagnosis of a clinical condition, it is essential that an absolute criterion of the clinical disease first be established. Then the sensitivity and the specificity of the test can be determined using appropriate experimental designs. The demonstration of a good correlation between a test outcome and a clinical condition is, of itself, insufficient grounds to use the test for diagnostic purposes.

Chemiluminescence in the assessment of polymorphonuclear leukocyte function in chronic inflammatory periodontal disease

Polymorphonuclear neutrophils (PMN's) constitute the primary host resistance factor against infection. They are prominent cells in both the gingival tissue and gingival sulcus in most forms of periodontal disease. Although defective PMN function has been implicated in the pathogenesis of localized juvenile periodontitis (LJP) and rapidly progressive periodontitis (RPP), this may not necessarily be the case in adult periodontitis (AP). A number of studies have failed to detect PMN dysfunction in AP. However, it may be that in this form of chronic inflammatory periodontal disease (CIPD) the defects in peripheral blood PMN function are subtle and the methods used may lack the necessary sensitivity. Chemiluminescence (CL) is the light energy produced by the PMN during its interaction with bacteria or other particles and has been demonstrated to correlate well with antibacterial integrity. Measurement of CL produced by phagocytically challenged PMN's may provide a very sensitive assay of the functional ability of these cells, and, hence, may be useful in assessing PMN activity in CIPD. Recent studies using PMN's obtained from periodontal diseased patients challenged with the periodontopathic organism Fusobacterium nucleatum have revealed an elevated CL response compared to non-diseased controls. These results are reviewed and areas for future research discussed.

Microbial populations and active tissue destruction in experimental periodontitis

Although specific subgingival microflora are being associated with active tissue destruction in periodontitis, little information exists on the relationship between subgingival flora and histological evidence of tissue destruction. The present study was undertaken to explore these relationships during experimental marginal periodontitis in squirrel monkeys. In 4 squirrel monkeys, experimental periodontitis was induced around bicuspids and molars using silk ligatures. The buccal part of the subgingival ligature was removed for bacterial sampling 3, 7, and 14 days after ligature placement. Dark-field microscopy was used to quantify motile forms, spirochetes, straight and curved rods, filaments, cocci and fusiforms. Subgingival plaque prior to periodontitis induction was dominated by cocci, but fusiforms and straight rods were also present. Spirochetes, filaments, curved rods and motile forms were absent. 3 days after induction of periodontitis, there were marked increases in spirochetes, motile forms, filaments, curved and straight rods. The proportions of coccoids and fusiforms decreased. The bacterial proportions stayed at approximately the same levels through 7 and 14 days. Histometric quantification of periodontal destruction showed loss of connective tissue attachment and crestal alveolar bone. A positive correlation was found between periodontal tissue destruction and both total number of subgingival bacteria and spirochetes.

The impact of research on scaling and root planing

The research expanding our knowledge of the periodontally involved root surface and its treatment is reviewed. To improve communication in the clinic and classroom, definitions are suggested for the terms "scaling" and "root planing." The objective and limitations of root planing procedures are discussed.

Bleeding/plaque ratio. A possible prognostic indicator for periodontal breakdown

The purpose of the present study was to investigate the clinical differences between individuals highly susceptible and individuals insusceptible to periodontal breakdown. The susceptible group consisted of 7 patients with a diagnosis of juvenile periodontitis. The insusceptible group consisted of 7 individuals selected on the basis of age (52 years or older), presence of at least 18 teeth, no evidence of extractions due to periodontal breakdown, no loss of attachment, shallow pockets, gross amounts of plaque and no history of interdental cleaning. Results showed that the susceptible group had more bleeding, less plaque and deeper pockets than the insusceptible group. Since the 2 groups seem to behave differently with regard to bleeding upon probing and amount of plaque, bleeding/plaque ratios were calculated. Testing showed a highly significant difference between the 2 groups. The same results were obtained if only sites with shallow pockets were included in the analysis. On the basis of these results, it is hypothesized that a high value of the ratio between bleeding and plaque may act as a prognostic indicator for periodontal breakdown.

Efficacy of clindamycin hydrochloride in refractory periodontitis. 12-month results

The purpose of this study was to evaluate the use of clindamycin hydrochloride as an adjunct to conventional periodontal therapy in the treatment of patients who had previously been unsuccessfully treated with scaling, periodontal surgery and the use of tetracycline. Thirteen patients with a history of "refractory" periodontitis were thoroughly scaled and monitored by repeated attachment level measurements for the presence of active destructive periodontitis. Disease activity was defined as a 3-mm loss in attachment from baseline measurements or the occurrence of a periodontal abscess. When active disease was detected, each patient was scaled again and placed on clindamycin hydrochloride 150 mg qid for 7 days. Following the adjunctive use of clindamycin in combination with scaling, the incidence of gingival sites demonstrating active disease in the group of 13 patients decreased from an annual rate of 10.7 to 0.5%. Each patient demonstrated a decreased incidence of active sites per unit of time. Clinical parameters such as probing depth, gingival redness, bleeding on probing and suppuration showed dramatic improvement at 12 months after clindamycin therapy. The percentage of pockets with probing depths greater than 6 mm, 4 to 6 mm and 1 to 3 mm changed from 11 to 2%, 38 to 24% and 51 to 74% respectively, following clindamycin therapy as compared to scaling alone. The percentage of sites bleeding on probing decreased from 33% after scaling alone to 8% following clindamycin and scaling. Gingival redness decreased from 36 to 1% of sites. Suppuration also decreased from 8% of buccal or lingual surfaces after scaling alone to 1% of surfaces following scaling and clindamycin.(ABSTRACT TRUNCATED AT 250 WORDS)

Pocket formation 3 years after comprehensive periodontal therapy. A retrospective study

The records of 50 adult patients were studied to determine the incidence of pocket formation 3 years following periodontal therapy. These patients were treated at the Post-graduate Periodontal Clinic of Tufts University School of Dental Medicine and were subsequently placed on a 3-month maintenance schedule. A total of 1080 teeth with probing depths of 3 mm or less at the end of active therapy were examined. Before treatment 305 teeth (28.2%) had probing depths of 1 to 3 mm, 480 (44.4%) had depths of 4 to 5 mm and 295 (27.4%) had depths of 6 mm or more. Three years after active treatment 944 teeth (87.4%) had probing depths of 1 to 3 mm, 110 (10.2%) had 4 to 5 mm depths and 26 (2.4%) had depths of 6 mm or more. Pockets developed more frequently in maxillary than mandibular teeth, in molars more than in any other tooth type and in those teeth which before treatment had pockets of 6 mm or more. Pockets were less likely to develop in patients with good plaque control and in patients below the age of 40.

Survival analysis of periodontal sites before and after periodontal therapy

Periodontal diseases appear to progress with bursts of destructive activity at individual sites. One effect of treatment might be to diminish the frequency of such bursts. Survival analysis was employed to seek such effects on the periodontal sites of 16 individuals with prior evidence of destructive periodontal disease. The subjects were monitored at bi-monthly intervals and actively breaking down sites were detected using attachment level measurements and the tolerance method of analysis. When active sites were detected, control sites of equal pocket depth and attachment loss were selected and microbiological and immunological samples were taken. The subjects were treated by modified Widman flap surgery and systemically administered tetracycline. On completion of therapy, bi-monthly monitoring was reinstituted. Life tables were constructed for periodontal sites in each of the 16 subjects prior to and after therapy. A site losing more than 3 mm of attachment at any time interval was considered to have relapsed or "died". Survivor functions were calculated for each time period indicating the % of sites which survived at any time. The subjects were divided into 3 categories on the basis of post-therapy survivor functions. The annual hazard rate in 9 good treatment response subjects (group 1) was reduced from 0.10/year to 0.01/year. The hazard rate of 5 intermediate treatment response subjects (group 2A) was reduced from 0.16/year to 0.04/year and that of 2 poor treatment response subjects (group 2B) from 0.15/year to 0.07/year. Group 2A and 2B individuals were combined and differences were sought in clinical, microbiological and immunological parameters between the good and poor treatment response groups. 5 out of 7 of the poor responding individuals showed elevated humoral antibody responses to 3 or more gram-negative subgingival species tested. Many of the elevated responses in this group were to organisms which are widely distributed and return quickly after therapy such as Fusobacterium nucleatum, Eikenella corrodens, Bacteroides intermedius and Capnocytophaga sputigena. The predominant cultivable microbiota in subgingival samples taken prior to therapy from the good responding group had significantly greater proportions of Actinobacillus actinomycetemcomitans, C. ochracea and B. intermedius than the poor responding group. The latter group showed significantly elevated proportions of F. nucleatum, Peptostreptococcus micros and Streptococcus intermedius.

Periodontal bone loss in dry mandibles of South African blacks: a biometric study

Periodontal bone loss associated with periodontitis results in increase in the distance between the cemento-enamel junction (CEJ) and the alveolar bone crest (ABC). This study analyzed periodontal bone loss in 100 mandibles of South African blacks who were never exposed to preventive or restorative dental treatment. Specimens were equally distributed over the third to the seventh decade of adult life. CEJ-to-ABC (CA) distances were measured along 4904 surfaces of 1076 teeth. Analysis of the measurements showed that, generally, CA distances increased with age; differences were substantial between the first and fifth age groups. The incisors were most severely affected in all age groups, and bone loss was less severe around posterior teeth. Pre-molars and second molars lost the least bone. No significant differences between measurements on the buccal, lingual, mesial, or distal surfaces for these teeth were found. Measurements on the right and left sides of the mandible did not differ significantly. These observations may, in part, have been influenced by mid-life loss of teeth caused by severe periodontitis; their absence from the sample may have masked the true extent of periodontal bone loss. The difference in age of eruption and, therefore, the difference in period of exposure to the oral environment may account for the more severe bone loss in the anterior teeth, especially in specimens from younger individuals (21-30 years).

Effect of non-surgical periodontal therapy. VI. Localization of sites with probing attachment loss

Incisors, cuspids and premolars in 49 patients with advanced chronic periodontitis were treated with initial, non-surgical periodontal therapy. The results were monitored by probing attachment level measurements at 6 sites of each tooth every 3rd month during a period of 24 months. A series of 9 probing attachment level measurements for each site was subjected to linear regression analysis. The slope of the regression line, the projected probing attachment loss during the 24-month interval (delta y) and the probability level of the slope were calculated for each site. 2 groups of sites with probing attachment loss were identified: group 1: sites with delta y greater than 1.5 mm and p less than 0.05; group 2: sites with delta y greater than 1.0 mm and p less than 0.05. Group 1 included 120 sites (5%) and group 2 included 265 sites (10%) of the total of 2532 available sites. In both groups, probing attachment loss was more frequently noticed for sites with an initial probing depth less than or equal to 3.5 mm than for sites with initial probing depth greater than or equal to 7.0 mm. The finding that the majority of sites with probing, attachment loss was found amongst initially shallow or moderately deep lesions may indicate attachment loss due to trauma associated with therapy rather than loss as a result of a continuing, inflammatory disease process.

The long-term effectiveness of periodontal therapy in a clinical practice

A retrospective study was conducted of 620 patients in a periodontal practice over the years 1960 to 1982. Various periodontal therapies were assessed by using careful office protocols, meticulous record-keeping and well-defined outcome criteria. Four treatment outcome categories were used: two representing satisfactory outcomes (referred to as "STABLE"), and two unsatisfactory outcomes ("UNSTABLE"). The percentages of patients in the STABLE categories following different therapies were: (1) nonsurgical treatment, 63.6%; (2) closed curettage, 73.1%; (3) open curettage, 95.0%; (4) modified Widman flap, 91.6%; (5) full flap and osseous surgery, 71.1%. The major conclusions were that the modified Widman flap and open curettage were more effective than flap and osseous surgery, and much more effective than closed curettage when it was employed as an alternative treatment (54.8% STABLE) to the osseous surgery (71.1% STABLE). Thus, moderate surgical therapies appear to be at least as effective as ostectomy procedures in the treatment of periodontal disease, while nonsurgical and closed curettage therapies appear to be less effective.

Root surface measurements of the mandibular first molar

The root surface area (RSA) per millimeter of root length was determined for 20 extracted mandibular first molars. The molars were cross-sectioned at 1-mm increments, and each section photographed, projected and measured with a calibrated opisometer. The RSA and per cent RSA were calculated for each 1 mm of root length (1-mm section), the root trunk and the individual roots. Also measured was the location of the root separations from the root trunk, the location of the first detectable root concavity, and the prevalence of "intermediate bifurcation ridges" (IBRs). Mean measurements indicated that the greatest RSA per millimeter of root length was 4 to 7 mm apical to the cementoenamel junction (CEJ) in the area of the furcation. Of the total RSA, 48.7% was located in the coronal 6 mm of a root (mean length, 14.4 mm). Root separation occurred 4.0 mm apical to the CEJ with no tooth having a root trunk longer than 6 mm. Buccal and lingual root concavities were first present 0.7 mm and 0.3 mm apical to the CEJ, respectively. Fourteen (70%) of the 20 teeth had IBRs. According to the mean measurements, the mesial root was larger than the distal root by a ratio of 1.0:0.88. Horizontal attachment loss of 6 mm affecting both the buccal and lingual surfaces of the mandibular first molar would have resulted in a through and through (grade 3) furcation involvement of all the teeth studied.

3-year longitudinal study of the periodontal status of an adult population with gingivitis

69 adults ranging in age from 20 to 73 (mean age: 37) were randomly assigned to a control (C) and a test (T) group. Of these, 61 completed the 3-year longitudinal study. All subjects had varying degrees of gingivitis at the start, but no overt periodontitis. Following a base line examination for P1I, GI, probing depth (PD) and recession, a differential darkfield microscopic (DDFM) count of subgingival bacterial morphotypes was carried out on a pooled sample originating from one tooth surface in each sextant with the greatest probing depth. Examinations were repeated every 6 months for 3 years. The C group received regular prophylaxes every 6 months. The T subjects received prophylaxes according to a previously described schedule, and on the basis of the DDFM test outcome. Recall intervals at the end of the study for the T group ranged from 1 to 24 months (mean: 15.7 months). Of 30 subjects in the T group at the end of the study, one half had not had their teeth cleaned for periods of 18 to 36 months without any detectable deterioration in their periodontal status by comparison with the other T subjects or the patients in the C group. Both C and T subjects exhibited increased mean P1I and GI scores as compared to base line during the first half of the study. However, mean PD measurements remained unchanged. Increases in PD from base line of 3 mm or more were observed only in approximately 1 out of a 1000 individual tooth surface comparisons, a frequency comparable to that expected to occur by chance alone. This observation indicates that in this population, little if any pocket formation occurred during the study period. GI score increases of 2 units or more occurred in relatively few subjects. 2 of 31 C patients accounted for 42% of the affected dental units, while 5 out of 30 T subjects accounted for 40.8% of the affected dental units in that group. These observations suggest that despite the relatively high prevalence and incidence of gingivitis, the subjects were relatively resistant to periodontitis. Neither preventive schedule was effective in eliminating gingivitis. The lack of significant destructive disease in this population prevented any meaningful comparison of the relative effectiveness of the two preventive maintenance regimens in preventing recurrences of periodontitis.

Periodontal diagnosis. Current status and future needs

This literature relating to current methods of periodontal diagnosis is reviewed. There exists a future need for objective diagnostic techniques which reflect the dynamics of periodontal disease activity.

Changing concepts in periodontics

This article has concentrated on aspects of periodontics where research over the last decade has demonstrated that old concepts are outmoded and for the patient's benefit should be changed in clinical practice. The following statements were made. Periodontal pockets do not need to be reduced surgically to a 3 mm limit to save teeth. Bone and soft tissues do not need to be sculptured to uniform horizontal atrophy at the level of the deepest pocket. Treated teeth can be maintained without loss of periodontal support with less than perfect plaque control if professional tooth cleaning every 3 months is practiced. Furcation involvement complicates the treatment of periodontitis, but such teeth have a better prognosis than has been commonly thought. Deep pockets have a relatively good prognosis after treatment. The problem is access for efficient root planing. Advanced periodontitis can be stopped in most patients. Gingival curettage does not improve the results of scaling and root planing. Support for teeth can be maintained without attached gingiva. Gingival blanching in response to lip pull is meaningless. Splinting is not needed for most teeth with increased mobility after periodontal therapy. It was acknowledged that in other controversial aspects of periodontics scientific information still is not available to support firm concepts that may guide clinical practice. One problem in dentistry is the lag that often exists between the publication of research findings and their application in clinical practice if there is no inherent economic reward in the new procedure.(ABSTRACT TRUNCATED AT 250 WORDS)

Longitudinal evaluation of durapatite ceramic as an alloplastic implant in periodontal osseous defects after 3 years

Seven patients who participated in a clinical study comparing the response of periodontal osseous defects to either grafting with Durapatite ceramic or debridement alone were followed under an active maintenance program for 3 years. Comparison of mean values showed that gingival recession, attachment levels and probeable pocket depths remained essentially stable for Durapatite sites over the 3 years. Attachment levels for debridement sites also remained constant, but these areas showed significant coronal migration of the free gingival margin and increases in probeable pocket depths. These latter changes became apparent and significant only after 3 years. Intrapatient comparisons showed that recession and attachment gain were most frequently greater and pocket depths most frequently less for Durapatite sites. These findings suggest that the Durapatite-treated sites were stable for 3 years following surgery, while areas treated with debridement alone regressed.

A longitudinal study of untreated periodontal disease

1016 textile workers were examined during a baseline study in 1969/70. A follow-up examination in 1979/80 identified 82 subjects who had not been treated for periodontal disease in the intervening period. There were 39 male and 43 female subjects; the average age at the initial examination was 27.0 years. There was an average tooth loss of 2.5 (SEM 0.6) teeth per subject over the 10-year period. While periodontal disease was significantly related to oral hygiene at the outset, neither factor was significantly related to the degree of tooth loss. A detailed analysis of the dynamics of the periodontal condition was undertaken. The subsequent results are presented in the form of transition matrices and clearly illustrate both the progression of periodontal disease and the degree of tooth loss associated with each level of periodontal disease at the initial examination. The main findings are as follows. (a) Overall 6% of teeth initially free of periodontal disease (P.I.O.) were lost compared to 14% with destructive periodontal disease (P.I.6). (b) Progression of periodontal disease was slow for teeth initially free of periodontal disease and with mild gingivitis (P.I.0 and P.I.1) for all age groups. However severe gingivitis (P.I.2), resulted in more rapid deterioration of the supporting tissues in subjects over 35 years old at the final examination; 35% of such teeth changed to destructive periodontal disease (P.I.6) compared to 17% of corresponding teeth for the under 35-year age group. In contrast, a poorer prognosis was found for the teeth with destructive periodontal disease (P.I.6) in the younger age group.(ABSTRACT TRUNCATED AT 250 WORDS)

Molar and nonmolar teeth compared over 6 1/2 years following two methods of periodontal therapy

Limited information is available comparing the relative longitudinal effectiveness with respect to tooth type of scaling and root planing alone and scaling and root planing followed by flap procedures. The purpose of this study was to investigate these treatment methods as applied to molar and nonmolar teeth on a longitudinal basis in humans. Seventeen subjects with chronic periodontitis received thorough scaling and root planning as well as oral hygiene instruction. A modified Widman flap was then randomly performed for one-half of each subject's dentition. Routine recall prophylaxis and oral hygiene reinforcement were administered postsurgically every 3 to 4 months. Pocket depth and clinical attachment levels were recorded by a single calibrated examiner before therapy and at intervals up to 61/2 years following active treatment. Ten subjects remained as participants after 61/2 years. A paired t test was used to test for the mean difference in pocket depth and clinical attachment level between molar and nonmolar teeth for each treatment method. For pockets initially 4 to 6 mm, the results indicated greater pocket depth and more apical clinical attachment level on molars than nonmolars treated by either method of therapy. For pockets initially greater than or equal to 7 mm there was no difference between pocket depth on molar and nonmolar teeth following scaling and root planing alone. However, there was less overall pocket depth on nonmolars than molars following the flap procedure, indicating a greater effect of pocket reduction on nonmolar than molar teeth with the flap procedure. No difference between tooth types was found for clinical attachment level in pockets initially greater than or equal to 7 mm with either treatment method. Both treatment methods resulted in at least maintenance of pretreatment attachment levels adjacent to molar and nonmolar teeth.

Long-term maintenance of patients treated for advanced periodontal disease

The aim of the present investigation was to evaluate the periodontal conditions of a group of patients who, following active treatment of extremely advanced periodontal disease, had been maintained for 14 years in a well-supervised maintenance care program. The present sample included 61 subjects out of an initial group of 75 individuals who in 1969 were referred to and treated by the authors. Following an initial examination, the patients were given detailed instructions in proper plaque control measures and were subjected to scaling and root planning and surgical elimination of pathologically deepened pockets. After the termination of the active treatment phase, the patients were placed in a maintenance care program including recall appointments every 3-6 months. At the initial examination, immediately after the completion of the active treatment phase and then once a year, all patients were examined regarding oral hygiene, gingival conditions, probing depths and clinical attachment levels. In addition, the interproximal alveolar bone height was determined from full mouth radiographs obtained before active treatment, at the completion of active therapy and 1, 3, 5, 8, 10, 12 and 14 years after treatment. The results from the repeated examinations demonstrated that treatment of advanced forms of periodontal disease resulted in clinically healthy periodontal conditions and that this state of "periodontal health" could be maintained in most patients and sites over a period of 14 years. It was also demonstrated that the treatment and maintenance programs described were equally effective in young and older patients. The individual mean values describing probing depths, attachment levels, and bone heights did not vary significantly over the 14 years of observation. A more detailed analysis of the data revealed, however, that a small number of sites in a few patients lost a substantial amount of attachment. This attachment loss occurred at different time intervals during the course of the maintenance period. Thus, 43 surfaces in 15 different patients were exposed to recurrent periodontal disease of a significant magnitude. This recurrent inflammatory periodontal disease caused the loss of 16 teeth in 7 different patients during the maintenance period. The data reported question the validity of using individual mean values to describe alterations of the periodontal conditions during maintenance following active periodontal therapy.

Aspartate aminotransferase increases in crevicular fluid during experimental periodontitis in beagle dogs

A ligature-induced periodontitis model employing the beagle dog was used to study the levels of aspartate aminotransferase (AST) in crevicular fluid before and after ligation. A significant increase in AST level occurred in crevicular fluid 2 weeks after ligation whereas no increase of enzyme was found in serum. Enzyme levels in crevicular fluid were 10- to 100-fold higher than in serum. Dental plaque did not appear to be the source of the enzyme. Since aspartate aminotransferase has been documented as a marker of cellular injury arising during heart disease and liver disease, this study suggests that aspartate aminotransferase, in like fashion, reflects cellular damage arising from active periodontal disease.

Periodontal treatment without maintenance. A retrospective study in 44 patients

This study presents our findings on 44 patients who were treated for periodontal disease and for varying reasons elected not to participate in the maintenance aspect of periodontal care. All patients were initially given intensive instructions in personal oral hygiene, along with initial scaling and root planing. Each patient had two or more quadrants of pocket reduction therapy. Tooth mortality revealed a mean annual adjusted tooth loss rate of 0.22 (4.7%). Between examinations, breakdown in the health status of furcations was noted. Mean probing depth scores at the second examination showed no significant differences from the first examination scores. Measurements of bone levels revealed a worsening of bone scores between examinations. The results of this study show that periodontal therapy without maintenance is of little value in terms of restoring periodontal health.

Comparative differential dark-field microscopy of subgingival bacteria from tooth surfaces with recent evidence of recurring periodontitis and from nonaffected surfaces

Ninety-two subjects with a history of treatment for chronic periodontitis were monitored on a regular basis for an average period of 10.7 months. During this monitoring period, in spite of their participation in a preventive maintenance program, 19 subjects out of 92 showed evidence of significantly increased probing depth (greater than or equal to 3 mm from base line measurements) on at least one tooth surface, or approximately 1% of the dental units at risk in this population. A comparison of differential microscopic counts of subgingival bacteria from the affected tooth surfaces with a pooled sample of 6 other surfaces with the greatest probing depth, in the same mouth, taken at the same appointment, revealed no significant differences between proportions of coccoid cells, spirochetes, motile rods or other cell types. These findings suggest that disease recurrence, as measured by a comparatively rapid increase in probing depth, might be accounted for on the basis of the following hypotheses: an alteration in the host response without a detectable change in the composition of the subgingival microbiota, a qualitative change in the microbial flora not detectable by a microscopic assay, relatively brief episodes of disease activity which may be accompanied by brief, transient, qualitative changes in the local microbiota that cannot be readily detected by biannual examinations.

Effect of age on the periodontium

It is generally known that the degree of periodontal breakdown increases with increasing age. The extent to which aging of periodontal tissues plays a part in this respect poses a question which is yet to be answered. Aging proves to be accompanied by a variety of periodontal changes. The periodontal tissues themselves show evidence of aging, there are indications that the composition of the plaque changes, and the reaction of the periodontium to the presence of plaque probably changes as well. There is as yet no sufficient evidence of a physiological apical migration of the epithelial attachment in human subjects. It seems plausible that periodontal breakdown can occur only in the presence of plaque with consequent inflammation of the periodontium, or as a result of trauma. Whether changes in plaque composition with age exert any influence on the course of periodontal breakdown is uncertain: the data available are not yet sufficient to warrant definite conclusions. The same applies to the influence which a changing reaction of the periodontium to the presence of plaque may have on the course of periodontal breakdown. Research findings do suggest that the degree of periodontal breakdown increases with age, that with increasing age inflammation of the periodontium tends to develop more rapidly and that in the process of aging the periodontium shows a slower rate of wound healing. However, these phenomena are overshadowed by the patients' susceptibility to periodontal disease. This implies that (1) the susceptibility to periodontal disease is more significant for the rate of periodontal destruction than the length of time plaque is present (the age effect) and (2) the greater the susceptibility to periodontal disease, the slower the rate of wound healing and the more rapidly inflammation of the periodontium tends to develop.

The relationship between attachment level loss and alveolar bone loss

Standardized radiographs and repeated periodontal probe measurements were made on 22 untreated subjects with destructive periodontal disease monitored for 1 year. Radiographs of selected sites were taken at 0, 6 and 12 months. Measurements of attachment level were made monthly. Radiographic measurements were made on 7X magnified projected images. Alveolar bone height from the CEJ was computed by multiplying the average length of the root times the measured ratio of CEJ to alveolar bone over CEJ to root tip. Each radiograph was measured twice by 2 investigators. Sites were excluded as having indistinct anatomical landmarks in which the standard deviation of the 4 measurements exceeded 0.16 mm, the measurement error for repeat determination of bone height on high quality radiographic images. A 3 sigma critical value for significant bone loss was selected as 0.48 mm. Changes in attachment level were computed for the intervals preceding and during the 6-12 month radiographic measurement period. Based on these critical values, 6.1% of the 231 radiographed sites showed significant bone loss. Similarly, 5.7% of the 1155 probed sites showed significant attachment loss. However, none of the sites with significant bone loss exhibited significant attachment loss over the same time period. In general, significant attachment loss preceded bone loss by 6 to 8 months. At 4 mm, attachment loss was found to predict subsequent bone loss with a true positive ratio of 60% and a false positive ratio of 5%, indicating a high degree of predictive discrimination. These observations indicate that attachment loss precedes radiographic evidence of crestal alveolar bone loss during periods of periodontal disease activity.

The acro-osteolysis (Hadju-Cheney) syndrome. Review of the literature and report of a case

Acro-osteolysis ( Hadju - Cheney ) Syndrome is a rare disorder of bone metabolism characterized by progressive destruction of the distal phalangeal bone, curvature of the spine, aplasia of the facial sinuses, and persistence of the cranial sutures. The purpose of this manuscript is to focus on the description of the oro-facial and dental manifestations of the disorder.

Effects of gold salts on experimental periodontitis. I. Histometric evaluation of periodontal destruction

Systemic administration of gold salts for treatment of arthritis is thought to limit tissue destruction through alteration of inflammatory cell function. The present study ascertained if gold salts could modify the tissue destruction associated with an experimental marginal periodontitis. Therapeutic levels of serum gold salts were established in four squirrel monkeys (experimental) by intramuscular injection of Myochrisine (gold sodium thiomalate 25 mg/ml) at 5 mg/kg/body weight at 4-day intervals for 12 days. Marginal periodontitis was then induced around mandibular bicuspids by tying plaque retentive ligatures at the gingival margins. Periodontitis was induced around corresponding teeth in four control animals which had not received gold salts. Serum levels of gold salts were maintained in experimental animals, and all animals were killed 2 weeks after induction of periodontitis. Progression of periodontitis was evaluated histometrically on step-serial sections, and the results analyzed statistically. Specimens from gold-receiving animals had significantly smaller areas of infiltrated supracrestal connective tissue, and less loss of connective tissue attachment and coronal alveolar bone. Quantitation of total plaque around the ligatures showed no differences; however, there was less plaque located apical to the ligatures in gold-receiving specimens. Although the study design did not permit identification of the relative importance of cellular or microbial factors, it was concluded that administration of systemic gold salts was associated with significantly less periodontal destruction.

Risk factors for various levels of periodontal disease and treatment needs in Iowa

A cross-sectional study of the non-institutionalized population of the State of Iowa was completed in 1980. Persons were interviewed by telephone and a follow-up dental examination was conducted in the home. Periodontal treatment needs were measured using the WHO-621 Index of Periodontal Treatment Needs which has been modified and is now known as the Community Periodontal Index of Treatment Needs. Findings were consistent with other recent studies, which have shown a relatively high proportion of gingival bleeding and calculus. Although moderate pocket formation (3-6 mm) occurs in approximately 30% of the adult population, complex treatment needs (pockets 6 mm or greater) occurred in only 1.3% of the population. While sex did not significantly affect the distribution of periodontal needs; age, recency of visit to the dentist and income are possible risk factors for serious periodontal disease.

Comparison of surgical and nonsurgical treatment of periodontal disease. A review of current studies and additional results after 61/2 years

Many well designed clinical studies have established the effectiveness of periodontal therapy. Surgical procedures have been shown to be effective in treating periodontitis when followed by appropriate maintenance care. Scaling and root planing alone have recently been compared to scaling and root planing plus soft tissue surgery in several longitudinal trials. A review of the literature indicates several important findings including a loss of clinical attachment following flap procedures for shallow (1-3 mm) pockets and no clinically significant loss after scaling and root planing. These studies also generally report either a gain or maintenance of attachment level for both procedures in deeper pockets (greater than or equal to 4 mm). For these pockets, neither procedure has been shown to be uniformly superior with respect to attachment gain. All reports indicate that both treatment methods result in pocket reduction. However, the literature also indicates that scaling and root planing combined with a flap procedure results in greater initial pocket reduction than does scaling and root planing alone. This difference in degree of pocket reduction between procedures tends to decrease beyond 1-2 years. It has been shown that both treatment methods result in sustained decreases in gingivitis, plaque and calculus and neither procedure appears to be superior with respect to these parameters. Additional data from the study at the University of Minnesota indicate that similar results are maintained up to 61/2 years following active therapy. Pocket depth did not change for shallow (1-3 mm) pockets treated by either scaling and root planing alone or scaling and root planing followed by a modified Widman flap. For pockets 4-6 mm, both treatment procedures resulted in equally effective sustained pocket reduction. Deep pockets (greater than or equal to 7 mm) were initially reduced more by the flap procedure. After 2 years, no consistent difference between treatment methods was found in degree of pocket reduction. However, as compared to baseline, pocket reduction was sustained to 61/2 years with the flap and only 3 years with scaling and root planing alone. After 61/2 years, sustained attachment loss in shallow (1-3 mm) pockets was found after the modified Widman flap. Scaling and root planing alone in these shallow pockets did not result in sustained attachment loss. For pockets initially 4-6 mm in depth, attachment level was maintained by both procedures but scaling and root planing resulted in greater gain in attachment as compared to the flap at all time intervals.(ABSTRACT TRUNCATED AT 400 WORDS)

The potential attachment area of the maxillary first molar

The assumption that the palatal (PAL) root of maxillary molars has significantly greater attachment area than either the mesiobuccal (MB) or the distobuccal (DB) root was tested by documenting the root surface area of the individual roots and root trunks of 20 extracted maxillary first molars. Each molar was cross sectioned every millimeter, and the circumference of each root and root trunk section was measured with a calibrated opisometer. Mean circumferential measurements from each 1-mm section were summed to give the surface area for each root and root trunk. The DB root had significantly less surface area than either the MB or PAL root or the root trunk. There was no significant difference between the surface areas of the MB and PAL roots. The surface area of the root trunk, which was significantly greater than that of any of the three individual roots, averaged 32% of the total root surface area of the maxillary first molar.

Comparison of different data analyses for detecting changes in attachment level

The purpose of the present investigation was to evaluate methods to detect periods of destructive periodontal disease activity in individual sites using pairs of repeated attachment level measurements. Attachment level measurements were made at 6 sites on every tooth in 22 individuals with radiographic evidence of periodontal destruction, and were repeated within 7 days. A total of 3414 sites were monitored at 2-month intervals for approximately 1 year. 3 analytical procedures were used to test for significant changes in attachment level. For regression analysis, a linear least squares fit function of time in days vs attachment level was computed for each site and the slope tested for difference from 0. Running medians of 3 were used to smooth attachment level measurements and changes greater than 2 mm in the smoothed curves were considered significant. By the tolerance method, differences between pairs of attachment level measurements were used to compare the mean change and the site specific variability of that change. The proportion of specific agreement (Ps) for breaking down sites was highest between the tolerance and running median methods (Ps = 0.63). Overall agreement (kappa), which included sites which showed "loss", "gain", and no change was 0.56. By regression analysis (P less than 0.01), 175 sites were identified as having significant attachment loss and 79 sites were identified as improving. By running medians these figures were 90 and 50, and by tolerance 94 and 40, respectively. Each of the 3 methods had certain advantages. Regression analysis was particularly sensitive to gradual changes in slope whereas the running median method detected abrupt changes in attachment level. The tolerance method was well suited to detecting changes over a short period of time. The tolerance and running median methods detected more breaking down sites on the molars and lower incisors and on interproximal surfaces; whereas regression analysis did not show these differences.

Bone loss of furcated mandibular molars. A longitudinal study

Periodontal bone destruction adjacent to furcations of molar roots has been considered to be unfavourable for the prognosis of the involved teeth. Several alternative modes of treatment have been reported. The objective of this study was to find out how important the furcation problem is. A study was conducted on the prevalence, degree and development of bone destruction between the roots of furcated mandibular molars in a sample of 221 individuals observed over a period of 13 years. The state of the interradicular bone septa was assessed from orthopantomographs and bite-wing radiographs. Radiographs were available from 1965, 1971, 1974 and 1978. The degree of bone destruction was measured in relation to the root length. About 90% of remaining molars (in 1965) were furcated. The frequency of bone destruction increased from 18% in 1965 to 32% in 1978. Only 1.1-2.7% of the molars had bone loss affecting more than 50% of the distance vertex to apex. About 9% of the furcated molars were lost during the observation period. However, the percentage of teeth lost due to progressive furcation involvement during the 13 years was estimated to be only 2.5%.

Differing profiles of periodontal disease in two similar South Pacific island populations

The periodontal condition of a cross-section of individuals aged between 15-59 years was characterised from clinical and radiographic observations of dental calculus, gingival inflammation, the level of the gingival attachment , alveolar bone loss, teeth missing or requiring extraction for periodontal reasons. The common characteristics of the profile in Tonga and W. Samoa were a high prevalence of the factors common to periodontal disease: calculus and gingival inflammation; a progressive apical movement of the gingival attachment; and alveolar bone loss. All these criteria showed a positive age dependency with calculus (particularly subgingival calculus) and gingival inflammation being very commonly associated with all tooth types at an early age, less than 30 years. Tooth loss observed was presumed to be previously associated with periodontal disease because the prevalence of dental caries was very low in both populations. Substantial differences were observed in the number of missing teeth between Tongan and Samoan populations, the Tongan subjects having a high rate of tooth loss. From radiographic interpretations of the periodontal conditions fewer subjects in Tonga were assessed as having no disease, and there was a higher prevalence of progressive destructive disease in Tonga than in W. Samoa. The proportion of subjects in both countries with no disease decreased rapidly with age. There was no evident explanation of the greater severity of disease in Tonga than in W. Samoa. The prevalence of microbial plaque, calculus and gingival inflammation was very high in all subjects at all ages particularly over 30 years in both populations.

Root fusion in molars: incidence and sex linkage

The study was done to determine the incidence and distribution of root fusion in 1340 maxillary and mandibular molars in 170 patients. A second objective was to determine whether root fusion of molars is sex-linked. A substantial percentage, 29% of all molars, had fused roots. Root fusion was found more frequently in maxillary than mandibular molars, 35% to 24%, and it occurred in many patients, rather than being limited to a few. Root fusion was most common in third molars, followed by second molars, in both jaws. It occurred in almost equal numbers in corresponding molars of opposite sides, approaching bilateral symmetry. The proportion of molars with root fusion was approximately 5% greater in females than in males, and about 13% more females had molar root fusion than males.

Clinical and radiographic long-term study of teeth with periodontal destruction treated by a modified flap operation

Forty-three patients with severe periodontal destruction were treated by a modified flap operation and their periodontal condition reassessed about 4 years later. The aim of the study was to see what would happen to the periodontium when the responsibility for oral hygiene was left to the patients themselves. Before the operation the importance of plaque in the etiology of periodontal disease was explained to the patients. They were requested to return for reexamination every 6 months, but no recall system was used. A highly significant reduction in the depth of the gingival pockets was achieved and the average loss of bony support during the observation time was only 0.3 mm. However, an increased bleeding index, loss of marginal bone and deepening of the gingival pockets were found around teeth provided with artificial crowns, especially when the crowns had ill-fitting margins extended into the gingival pocket.

An overview of periodontal surgical procedures

It is obvious from the foregoing that there are many technical approaches to periodontal surgery. The mere presence of a periodontal pocket of a cerain depth as the major indicator for surgery is not as steadfast as once believed. Other criteria such as hemorrhage and exudate must also be used in evaluating the need for surgery. The decision on which approach to use remains with the therapist and the individual situation which he/she is faced. However, in the past decade it has become increasingly clear that the need for so-called more advanced surgical procedures is not as important to the control of periodontal diseases as was once thought. Regardless, it is also clear that some form of surgical intervention, as defined by this paper, is still necessary to interrupt the sequence of events that make up the pathogenesis of periodontal disease that leads to eventual tooth loss. This paper has reviewed and evaluated some of the current procedures available to the therapist in the surgical approach to therapy.