Studies on the relationship between changes in radiographic bone height and probing attachment

Periodontal status of hypothyroid patients on thyroxine replacement therapy: A comparative cross-sectional study

Background:

Thyroid hormones play a significant role in bone remodeling. However, there are few studies on the effect of these hormones on periodontium.

Aim:

The aim of this study was to evaluate the periodontal status of hypothyroid patients on thyroxine replacement therapy.

Materials and Methods:

Clinical parameters (plaque index, bleeding index, probing pocket depth [PPD], and clinical attachment level [CAL]) and radiographic parameters (Mandibular cortical width and panoramic mandibular index) were recorded in 52 hypothyroid patients on thyroxine replacement therapy (Study group) and 50 individuals without signs and symptoms of thyroid dysfunction (Control group). The effect of dosage and duration of therapy on clinical and radiographical parameters were also assessed in the study group.

Results:

Statistically significant higher PPD (P = 0.008) and clinical attachment loss (P = 0.032) were observed in the study group in comparison to the control group. However, no significant differences were observed within the hypothyroid group with varying doses and duration of therapy. Furthermore, there was no correlation between the dosage and duration of therapy with periodontal status. Regression analysis showed that hypothyroidism and thyroxine replacement therapy was a significant predictor of PPD and CAL even after controlling for the effect of age in hypothyroid patients.

Conclusion:

Hypothyroid patients on thyroxine replacement therapy may be at increased risk for periodontal destruction. However, this needs to be validated through longitudinal studies.

Marginal bone level in two Danish cross-sectional population samples in 1997-1998 and 2007-2008

OBJECTIVE

The aim of this study was to compare the marginal bone level of two randomly selected population samples from 1997/1998 and 2007/2008, with special emphasis on the role of smoking habits and gender.

MATERIALS AND METHODS

Two cross-sectional randomly selected population samples [1997/1998 (N = 616) and 2007/2008 (N = 396)] were analysed with respect to the marginal bone level. The marginal bone level was measured in full-mouth intraoral radiographs. Information on smoking was gathered using questionnaires. Multiple regression analysis was used in order to adjust for correlating factors (gender, age, smoking habits and number of teeth).

RESULTS

After adjusting for confounding factors, the population sample from 2007/2008 had on average a slightly, but statistically significantly, more reduced average marginal bone level (0.15 mm) than the population sample from 1997/1998. Men had more reduced marginal bone level than women (0.12 mm). Smokers in both population samples had more reduced marginal bone level than non-smokers (0.39 mm and 0.12 mm for 1997/1998; 0.65 mm and 0.16 mm for 2007/2008).

CONCLUSIONS

In these populations, sampled 10 years apart, the 2007/2008 population sample had a slightly more reduced marginal bone level than the 1997/1998 population sample. Men had more reduced marginal bone level than women, and smoking is considered a major risk factor for a reduced marginal bone level.

Is Radiologic Assessment of Alveolar Crest Height Useful to Monitor Periodontal Disease Activity?

The mainstay of periodontal assessment is clinical probing. Radiographic assessment provides quantitative information on the status of tooth-supporting bone. This article reviews methods to assess periodontal structures, including basic radiograph acquisition, assessment of alveolar crest levels, and typical patterns of bone loss. Computer technology to objectively assess loss of alveolar crest from radiographs is reviewed. Developments in computer-assisted quantitation of alveolar crest height are described. Although probing measurements continue to be viewed as more practical than radiographic measurements, radiographic assessment can be made quantitative and is likely easier and more precise than probing for routine assessment of periodontal disease activity.

The association between clinical and radiographic periodontitis measurements during periodontal maintenance

BACKGROUND

The purpose of the present study is to examine the association between clinical and radiographic periodontitis measurements during 2 years of periodontal maintenance.

METHODS

Secondary analyses were performed from a 2-year, double-masked, placebo-controlled, randomized clinical trial evaluating the efficacy and safety of subantimicrobial dose doxycycline (SDD) in 128 postmenopausal osteopenic females with moderate-to-severe chronic periodontitis. Relative clinical attachment level (relative CAL) and probing depth (PD) measurements were made. Posterior vertical bitewings were taken for alveolar bone density (ABD) and alveolar bone height (ABH) measurements. Generalized estimating equations were used to model associations.

RESULTS

One-year ABD changes and 1-year relative CAL/PD changes did not predict 2-year ABH changes and ABH/ABD changes, respectively. Baseline relative CAL and PD were positively associated with baseline ABH loss (P <0.0001), and baseline PDs were associated with subsequent ABD and ABH loss (P <0.05 for each). Among placebo (but not SDD) participants, relative CAL changes were associated with concurrent ABD loss (P = 0.027) when considering 1- and 2-year changes combined. The odds of ABH loss were higher among sites with concurrent 1-year ABD loss versus no change (odds ratio [OR] = 3.15, P <0.0001) or concurrent PD increases versus no change (OR = 1.88, P = 0.0025) when considering 1- and 2-year changes combined.

CONCLUSIONS

In postmenopausal osteopenic females undergoing periodontal maintenance, baseline PD was associated with subsequent ABD and ABH loss. Although no longitudinal change preceded another measurement change, changes in PDs and relative CALs appeared to reflect changes in the underlying alveolar bone over time.

Prevalence of Periodontal Bone Loss in Brazilian Adolescents through Interproximal Radiography

Purpose. The aim of this study was to verify the prevalence of alveolar bone loss in Brazilian adolescents through the interproximal X-rays analysis. Methods. Bilateral and standardized interproximal (bitewing) X-rays were performed in 15-year-old adolescents (n = 326), and the processing of films and measurements of alveolar bone levels were accomplished by a single examiner. A distance between the cementoenamel junction (CEJ) and the alveolar bone crest more than 2 mm was considered as periodontal bone loss. Results. The results showed percentage of bone loss of 10.4% with predominance of horizontal defects (8.9%) over the vertical types (1.5%). It was verified higher individual distribution of one lesion (67.6%) than two (26.5%) or three lesions (5.6%), and higher occurrence was detected in men (14.95) than in women (8.21). Conclusion. It can be concluded that the interproximal radiography was an efficient method for the detection of alveolar bone loss, revealing low prevalence in adolescents and predominance of horizontal bone defects.

Alveolar bone measurement precision for phosphor-plate images

OBJECTIVES

The aim was to demonstrate methods for determining measurement precision and to determine the precision of alveolar bone measurements made with a vacuum-coupled positioning device and phosphor plate images.

STUDY DESIGN

Subjects were rigidly attached to the x-ray tube by means of a vacuum coupling device and custom cross-arch bite plates. Original and repeat radiographs (taken within minutes of each other) were obtained of the mandibular posterior teeth of 51 subjects, and cementoenamel junction-alveolar crest (CEJ-AC) distances were measured on both sets of images. In addition, x-ray transmission (radiodensity) and AC height differences were determined by subtracting one image from the other. Image subtractions and measurements were performed twice. Based on duplicate measurements, the root mean square standard deviation (precision) and least significant change (LSC) were calculated. LSC is the magnitude of change in a measurement needed to indicate that a true biologic change has occurred.

RESULTS

The LSCs were 4% for x-ray transmission, 0.49 mm for CEJ-AC distance, and 0.06 mm for crest height.

CONCLUSION

The LSCs for our CEJ-AC and x-ray transmission measurements were similar to what has been previously reported. The LSC for AC height (determined with image subtraction) was <0.1 mm. Compared with findings from earlier studies, this represents a highly precise measurement of AC height. The methods demonstrated for calculating LSC can be used by investigators to determine how large changes in radiographic measurements need to be before the changes can be considered to be (with 95% confidence) true biologic changes and not noise (i.e., equipment/observer error).

Case definitions for use in population-based surveillance of periodontitis

Many definitions of periodontitis have been used in the literature for population-based studies, but there is no accepted standard. In early epidemiologic studies, the two major periodontal diseases, gingivitis and periodontitis, were combined and considered to be a continuum. National United States surveys were conducted in 1960 to 1962, 1971 to 1974, 1981, 1985 to 1986, 1988 to 1994, and 1999 to 2000. The case definitions and protocols used in the six national surveys reflect a continuing evolution and improvement over time. Generally, the clinical diagnosis of periodontitis is based on measures of probing depth (PD), clinical attachment level (CAL), the radiographic pattern and extent of alveolar bone loss, gingival inflammation measured as bleeding on probing, or a combination of these measures. Several other patient characteristics are considered, and several factors, such as age, can affect measurements of PD and CAL. Accuracy and reproducibility of measurements of PD and CAL are important because case definitions for periodontitis are based largely on either or both measurements, and relatively small changes in these values can result in large changes in disease prevalence. The classification currently accepted by the American Academy of Periodontology (AAP) was devised by the 1999 International Workshop for a Classification of Periodontal Diseases and Conditions. However, in 2003 the Centers for Disease Control and Prevention and the AAP appointed a working group to develop further standardized clinical case definitions for population-based studies of periodontitis. This classification defines severe periodontitis and moderate periodontitis in terms of PD and CAL to enhance case definitions and further demonstrates the importance of thresholds of PD and CAL and the number of affected sites when determining prevalence.

Radiographic measures of chronic periodontitis and carotid artery plaque

BACKGROUND AND PURPOSE

Chronic periodontitis (CP) is associated with stroke and subclinical atherosclerosis, but clinical measurement of CP can be time consuming and invasive. The purpose of this study was to determine whether radiographically assessed CP is associated with nonstenotic carotid artery plaque as an ultrasound measure of subclinical atherosclerosis.

METHODS

Panoramic oral radiographs were obtained from 203 stroke-free subjects ages 54 to 94 during the baseline examination of the Oral Infections and Vascular Disease Epidemiology Study (INVEST). CP exposure among dentate subjects was defined either categorically (periodontal bone loss > or =50% [severe] versus <50% bone loss) or via tertile formation (for dose-response investigation), with edentulous subjects categorized separately. In all subjects, high-resolution B-mode carotid ultrasound was performed. Carotid plaque thickness (CPT) and prevalence (present/absent) were recorded. Covariates included age, sex, smoking, diabetes, hypertension, low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein cholesterol.

RESULTS

Among dentate subjects with severe periodontal bone loss, mean CPT was significantly greater (1.20+/-1.00 mm versus 0.73+/-0.89 mm; P=0.003). CPT increased with more severe bone loss (upper versus lower tertile bone loss; P=0.049; adjusted for age, sex, and hypertension). This apparent dose-response effect was more evident among never-smokers. In a fully adjusted multivariate logistic regression model, severe periodontal bone loss was associated with a nearly 4-fold increase in risk for the presence of carotid artery plaque (adjusted odds ratio, 3.64; CI, 1.37 to 9.65).

CONCLUSIONS

Severe periodontal bone loss is associated independently with carotid atherosclerosis. Panoramic oral radiographs may thus provide an efficient means to assess CP in studies of atherosclerosis risk.

The relationship between radiographic and clinical parameters in periodontal maintenance in class II furcation defects

The goal of the present study was to investigate the relationship between probing and radiographic parameters, and the reliability of repeated longitudinal periodontal probing measurements for early diagnosis of periodontal breakdown in class II furcation defects. Eighteen class II furcation defects in lower molars were included in this study. Standardized radiographs and clinical measurements, relative vertical clinical attachment level (CAL-v) and probing depth (PD) were obtained immediately before periodontal surgeries and at 6, 12, 18, and 24 months after surgery. A total of 72 pairs of radiographs were subtracted following correction for contrast and planar geometric discrepancies, and the bone loss/gain (in mm) was measured. There was no statistically significant correlation between CAL-v and bone height (BH) measurements. A statistically significant correlation for PD reduction at 24 months and BH increase at 18 months was found (r = 0.5, p < 0.05). These results suggest that clinical measurements and radiographic bone height reflect different features of periodontal destruction and periodontal healing, and repeated longitudinal measurements of vertical clinical attachment level are not reliable for early diagnosis of periodontal breakdown in class II furcation defects.

Position Paper: Diagnosis of Periodontal Diseases

At the present time, the diagnosis and classification of periodontal diseases are almost entirely based on traditional clinical assessments. Supplemental quantitative and qualitative assessments of the gingival crevicular fluid and subgingival microflora can potentially provide useful information about the patient's periodontal disease. In certain situations, these supplemental risk-assessment tests may be particularly valuable in establishing the endpoint of therapy prior to placing patients on a periodontal maintenance program. Although the clinical utility of none of these tests has been validated, their further development is warranted. A genetic test for susceptibility to periodontitis has become commercially available. How best to use this and future host-based tests in clinical practice remains to be determined. Probing depth and clinical attachment loss measurements obtained with periodontal probes are practical and valid methods for assessing periodontal status. Computer-linked, controlled-force electronic periodontal probes are commercially available and are currently in use by some practitioners. Many of the logistical problems associated with subtraction radiography are being overcome and this powerful diagnostic tool may soon come into widespread use. Future developments in this and other imaging techniques are likely to have a profound effect on our approach to the diagnosis of periodontal diseases.

The pattern of alveolar crest height change in healthy postmenopausal women after 3 years of hormone/estrogen replacement therapy

BACKGROUND

The loss of ovarian function at menopause is associated with loss of postcranial and oral bone. Hormone/estrogen replacement therapy (HRT/ERT) has a positive effect on both postcranial and oral bone. The objective of the study was to determine if the positive effect of HRT/ERT on alveolar crest height (ACH) is generalized or site specific.

METHODS

The sample consisted of 49 women who completed a 3-year, HRT/ERT prospective study. Cemento-enamel junction distances (ACH) were measured on digitized images of bitewing radiographs. Lumbar spine and proximal femur bone mineral densities (BMDs) were determined with dual-energy x-ray absorptiometric scans. Measurements were made at baseline and at the end of year 3. For the 3-year study period, mean change in ACH was determined for each patient. In addition, the sites with the greatest, second and third greatest ACH changes were determined for each patient. Correlations between changes in ACH (as determined by the various methods) and postcranial BMD were determined.

RESULTS

Mean ACH changes had an average correlation (r) of -0.24 with femoral and lumbar spine BMDs. Although the largest site-specific change in ACH resulted in a mean correlation of -0.21, the correlations for the second and third largest changes in ACH dropped to -0.15 and -0.12. Overall, the correlations for site-specific changes were substantively smaller than those for generalized change.

CONCLUSIONS

The data of this study indicate that ACH change attributable to HRT/ERT is generalized rather than site specific. Studies of the effect of HRT/ERT on ACH should employ multiple measurements to minimize measurement errors associated with site-specific measurements.

Radiographic patterns of periodontitis in cats: 147 cases (1998-1999)

OBJECTIVE

To determine patterns of alveolar bone loss (periodontitis) and other lesions evident on full-mouth survey radiographs of cats.

DESIGN

Retrospective study.

ANIMALS

147 cats.

PROCEDURE

Full-mouth radiographs were evaluated for evidence and severity of alveolar bone loss, odontoclastic resorption lesions (ORL), retained roots, missing teeth, signs of endodontic disease secondary to periodontitis, and apical resorption.

RESULTS

106 (72%) cats had some degree of periodontitis, 100 (68%) were missing teeth, 98 (67%) had ORL, 78 (53%) had expansion of the buccal alveolar bone at 1 or more canine teeth, 75 (51%) had retained roots, 48 (33%) had apical resorption, and 12 (8%) had signs of endodontic disease secondary to periodontitis. Cats < 4 years old were not significantly more likely than the general population to have normal alveolar bone height. Prevalence of ORL increased with age, but cats > or =13 years old were less likely than the general population to have moderate or severe generalized periodontitis. Purebred cats were not significantly more likely to have periodontitis or ORL than mixed-breed cats.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggest that periodontitis is common in cats and that horizontal bone loss is the most common radiographic pattern of alveolar bone loss. Purebred cats were not more likely than mixed-breed cats to have ORL or periodontitis, but when they did have periodontitis, it was more likely to be moderate to severe. Cats with ORL were less likely than cats without ORL to have normal alveolar bone height and more likely to have severe focal vertical bone loss.

Periodontal tissue responses after insertion of artificial crowns and fixed partial dentures

PURPOSE

The purpose of this review was, first, to critically evaluate published evidence on the effects of artificial crowns and fixed partial dentures (FPDs) on adjacent periodontal tissue health, and second to synthesize this evidence into meaningful summaries. Restoration qualities that contribute to inflammatory responses were identified based on strength of evidence, and variables that should be controlled in future investigations were outlined. Such information is necessary to accurately predict the prognosis of periodontal tissues adjacent to crowns or FPDs.

METHODS

Clinical trial and epidemiologic evidence published in English was collected. The effects of crowns or FPDs on gingival inflammation, probing depths, and bone loss were evaluated based on accuracy of measurement, reliability of measurement, and/or appropriateness of data analysis.

RESULTS

Crowns and FPDs increased the incidence of advanced gingival inflammation adjacent to restorations, particularly if restorations had intracrevicular finish line placement, poor marginal adaptation, or rough surfaces. However, because of the limitation in the accuracy and reliability of probing depth measurements, reports of greater mean probing depths of crowned teeth, which tended to be less than 1 mm greater than control teeth, should be questioned. Finally, crowns and FPDs in general did not accelerate the rate of adjacent bone loss.

CONCLUSION

Clinically deficient restorations, as well as clinically acceptable restorations, can contribute to gingival inflammation. However, with the limitations of the applied methods of measurement, current evidence has not shown an increased attachment loss adjacent to crowns or FPDs. Future trials should document periodontal health before therapy and periodically after restoration insertion so that each tooth serves as its own control. In future studies, the periodontal disease history of the patient, the influence of the restoration on plaque formation, and the composition of the crevicular microflora must be recorded.

Outcome variables in periodontal research: means and threshold-based site changes

BACKGROUND

The exclusive use of mean measurements in periodontal research might at times be misleading, as changes in different sites in the same individual might nullify each other. The purpose of the present study was to compare disease progression and response to periodontal therapy using both individual site activity with thresholds and mean patient changes.

METHODS

Seventy-nine (79) subjects with established periodontitis were monitored for 1 year (no treatment [NTx] group); 108 subjects who received scaling, root planing, and quarterly prophylaxis were observed in a similar time interval (treatment [Tx] group). Probing depth (PD), attachment level (AL) and alveolar crestal height (ACH) were measured at baseline and 1 year using pressure-sensitive probes and computer-assisted image analysis of radiographs.

RESULTS

Mean reduction in PD (0.50 mm) was observed in the Tx group compared to a small increase (-0.04 mm) in the NTx group (P= 0.0001). Treatment resulted in mean AL gain (0.44 mm) compared to net AL loss (-0.21 mm) in the NTx group (P= 0.0001). Subjects in the Tx group had twice as many sites with AL gain (beyond the threshold) compared to NTx subjects (16.64+/-1.07% versus 8.11+/-0.68%) which was highly significant (P = 0.0001, Student t test). Similarly, although in the opposite direction, percentage of sites with AL loss beyond threshold was 6.21+/-0.47% (Tx group) and 14.02+/-1.15% (NTx group) which was also highly significant (P = 0.0001, Student t test). Change in ACH was minimal for the Tx group (-0.07+/-0.03 mm) while NTx subjects experienced greater bone loss throughout the year (-0.16+/-0.02 mm); percentage of sites with ACH loss was similar for both groups, while the Tx group had 3 times the number of sites with ACH gain (11.76% versus 3.42%), suggesting that the reduction in mean bone loss in the Tx group did not result from a reduction in losing sites, but rather from an increase in gaining sites. The use of both means and binary data seems to supplement the information regarding the nature and mechanism of disease progression and arrest.

CONCLUSIONS

The characteristics of periodontal disease with its multifactorial patient, local, and site-related etiology support the use of both mean and site-based changes in clinical studies of periodontal disease and treatment.

Radiographic and digital imaging in periodontal practice

This review defines terms such as accuracy, validity, and reliability, which are used to describe the quality of methods for taking x-rays and for analyzing digital images. Values for these parameters are described for techniques of taking standardized x-rays such as ear-rod fixation and fixation by use of teeth with a dental impression. In addition, values are given for linear measurements on digitized images and for quantitative image subtraction. Differences are addressed between quantitative subtraction with a reference ramp and relative subtraction using the computer-assisted densitometric image analysis (CADIA) system. The relationship between radiographic bone height and clinical attachment level is also discussed. Finally, present and future use in the periodontal office of linear radiographic measurements on digital images and digital subtraction is discussed.

Relationships between longitudinal changes in radiographic alveolar bone height and probing depth measurements: data from postmenopausal women

BACKGROUND

The relationship between loss of radiographic alveolar bone height and probing attachment loss has been studied by a number of investigators, with mixed results. Recent studies have found weak correlations and have suggested that the relationship between bone loss and attachment loss is complex, perhaps because changes in bone height and attachment level are separated in time.

METHODS

The 85 patients in this report were part of a prospective estrogen replacement interventional study. All patients were in good oral health at entry and received annual oral prophylaxis as part of the study. Standard probing measurements were made with a pressure-sensitive probe at 6 sites on each tooth. Vertical bite-wing radiographs were taken of each patient, radiographs were digitized, and 6 linear measurements (corresponding to probing site measurements) were made from the cemento-enamel junction to the alveolar crest. These procedures were performed at baseline and at annual intervals; this study reports results after 2 years. Data were analyzed both by individual site and by averaging identical sites from all measured teeth for each patient.

RESULTS

Very weak direct relationships between change in alveolar bone height and change in attachment level were found in both the site data (r2=0.0022; P = 0.189) and the patient average data (r2=0.031; P= 0.104).

CONCLUSIONS

The changes in these patients were probably due to systemic changes in bone health rather than to periodontal disease. However, the weak correlations between changes in attachment level and bone height are similar to recent studies of periodontal disease. Our results support suggestions in the literature that the link between changes in attachment and alveolar bone height is complex, perhaps because changes in the 2 tissue types are separated by a considerable time delay.

Attachment loss in rural Chinese children over a 3-year period

OBJECTIVES

The periodontal condition of 84 children (9-14 years old, 38 males and 46 females) in a rural area of China was monitored over a 3-year period in order to determine the clinical parameters that act as risk factors for attachment loss.

METHODS

Plaque and calculus accumulation (PSS and CI), modified gingival index (MGI), pocket depth (PD) and attachment level (AL) of two quadrants of each child were examined in 1993 and 1996. Following calculation of the mean of each of these parameters and statistical analysis of the change in each of the clinical parameters over the 3-year period, the relationship between attachment loss and clinical parameters was analyzed using multiple regression analysis.

RESULTS

At the beginning of this study, the mean values for males and females were 3.66 and 3.58 for PSS, 1.22 and 1.17 for MGI, 1.07 and 0.90 for CI, 2.21 and 2.22 for PD, and both 0.02 for AL respectively. No significant difference between males and females was observed. After 3 years, all except mean PSS had increased significantly. Multiple regression analysis indicated that AL correlated only to age (P<0.01). In 1993, although the AL was > or =1 mm for at least one site in 21 children, none had an AL> or =3 mm. In 1996, the number of children with an AL> or =1 mm had increased to 63, and nine of these children exhibited 3 mm AL (one to six sites per child). No other significant differences were observed between the clinical data of these nine children and those of the other children.

CONCLUSION

Although attachment loss tended to increase with age, no clinical parameters correlated with attachment loss in children.

Option-4 algorithm for third generation disc probe: agreement of selected site-specific relative attachment level measurements and detection of longitudinal site-specific attachment level change

BACKGROUND

Longitudinal site-specific attachment level change (SSAC), identified from serial relative attachment level measurements (RAL), is the principal indicator of progression/regression of periodontal diseases. Many variables confound RAL reproducibility and affect measurement error. The Option-4 algorithm was designed to reduce measurement error and improve accuracy and sensitivity of SSAC detection. The study aimed to evaluate the performance of the Option-4 algorithm.

METHODS

A precalibrated clinician recorded full mouth RAL with a third generation disc probe on 4 occasions over 6 months in 16 subjects (mean age 48.1 years) with moderately advanced chronic adult periodontitis (2,312 sites). Option-4 allowed up to 4 RAL recordings per site per visit until 2 values had differences < or =1.0 mm and their mean was < or =1.0 mm from the previous visit mean: the clinician made the selection if these criteria were unfulfilled.

RESULTS

Within-visit agreement < or =1.0 mm was > or =99.6%: all within-visit correlation coefficients = 0.98 (P<0.001). At each visit, mean difference in Option-4 values was < 0.05 mm, mean absolute difference (ignoring direction) was < or =.34 mm. Mean site-specific variances ranged from 0.092 mm2 to 0.097 mm2 across all visits. Subject thresholds for site-specific attachment level change (from estimated 95% confidence limits of visit 1 data) ranged from 0.52 mm to 0.67 mm. Linear SSAC (by linear regression) and between-visit patterns of SSAC were investigated. SSAC was detected in 100% subjects and at 51.0% measured sites. Linear SSAC (R2 > or =0.90: P < or =0.05) occurred at 105 sites (4.5%): 32 sites (1.4%) deteriorated, 73 sites (3.1%) improved. Between-visit SSAC occurred at 1,074 sites (46.5%): 391 sites (16.9%) deteriorated, 295 sites (12.8%) improved, and 388 sites (16.8%) showed exacerbation/remission patterns.

CONCLUSIONS

The Option-4 algorithm produced high RAL agreement. Site-specific attachment level change was detected in both directions in 100% subjects and at 51.0% measured sites.

Reliability of linear alveolar bone loss measurements of mandibular posterior teeth from digitized bitewing radiographs

Observer reliability in performing linear measurements between the cementoenamel junction and alveolar crest was determined for mandibular posterior teeth from digitized clinical bitewing radiographs acquired during recall examinations. 6 measurements (corresponding to traditional probing measurements) were made per tooth by 3 observers. Mesial and distal measurements made to the most coronal aspects of the alveolar crest were the most reliable and least biased. As was anticipated, intra-observer reliability was better than inter-observer reliability although the 3 observers of our study were able to detect a significant mean change (0.1 mm, p<0.0001) in alveolar bone height over a 1-year period for 10 patients. For our most reliable and unbiased measurements (mesial measurements to the alveolar crest), a change of 0.54 mm (90th percentile) would be required to indicate change at a site from one time to the next. Based on the reliability of our digital radiographic measurements, with the alpha error rate set at 0.05 and beta at 0.20, a difference in alveolar bone height of 0.3 mm could be detected with a patient sample size of between 13 (best case) and 54 (worst case).

Acceptance Program Guidelines. Products and methods for the diagnosis and/or management of periodontitis. Council on Scientific Affairs. American Dental Association

SCOPE

These Guidelines apply to the design of clinical trials to evaluate products and methods which are intended to be used for the detection and diagnosis of periodontitis. The general purpose for such products and methods would be to assist in the identification of sites or subjects with existing periodontitis or, at increased risk of periodontitis, or for the development or progression of periodontitis. Clinical use of such diagnostics might occur: 1) during initial evaluation (screening, pre-treatment risk assessment, diagnosis, treatment-planning); 2) during treatment or management (monitoring therapeutic endpoints, identifying therapeutic targets); and 3) post-treatment (establishment of recall intervals, early detection of recurrent disease). The specifics of clinical trial design for each of these related, but separate, clinical functions may differ depending on a variety of circumstances.

Radiographic periodontal findings in an elderly Finnish population

By means of panoramic radiography and additional intraoral radiographs, the occurrence of calculus, the extent of horizontal bone loss, the depth and number of infrabony pockets, the number of furcation lesions, and the number of interproximal restoration overhangs were studied in 169 dentate 76-, 81-, and 86-year-old subjects (54 male and 115 females) living at home. Alveolar bone loss (horizontal or vertical) among the participants was common, and in only 8 subjects (5%) was it judged non-existent. It was slight in 30 subjects (18%), moderate in 53 (31%), and advanced in 78 (46%). Infrabony pockets were found in 51% of the subjects and furcation lesions in 28%. The presence of calculus did not correlate with the other parameters. The number of interproximal overhangs was associated with the number of infrabony pockets and of furcation lesions (R=0.3, p<0.001 and p<0.0001) and the number of infrabony pockets with the number of furcation lesions (R=0.4, p<0.0001). Our study shows that periodontal findings are common in the dentate elderly, and associations recently found between periodontal infections and several serious diseases make radiographic examination an integral part of the oral examination of the elderly patient.

Radiographic and clinical responses to periodontal therapy

Mechanical periodontal therapy is widely used for a variety of periodontal conditions. While the clinical efficacy of this treatment has been validated, the radiographic response has not been studied in depth. The purpose of the present study was to examine the clinical and radiographic response to mechanical periodontal therapy, and assess the factors associated with these changes. One hundred and eight patients, with established periodontitis, received oral hygiene instruction and mechanical periodontal therapy for a period of 4 to 5 weeks. Scheduled maintenance visits were performed at 3, 6, 9, and 15 months. Probing depth (PD) and attachment level (AL) measurements were performed at baseline, and at 3 and 15 months. Intraoral radiographs were taken at baseline and 12 to 15 months postsurgery using a Rinn alignment system. Alveolar crestal height (ACH) measurements were performed on a pair of digitized images of the previously taken radiographs. An overall mean of patients' changes for PD, AL, and ACH was initially computed. Active sites (gainers and losers) were determined using a threshold method, and expressed as patient's percentage of active sites (number of active sites of the total sites measured in each patient). Mean overall probing reduction and AL gain was 0.5 mm and 0.44 mm, respectively. Of all sites measured, 16.6% exhibited AL gain, while only 6.2% of all sites exhibited AL loss. Mean overall change in ACH was -0.07 mm, of which 11.8% of all sites exhibited ACH gain, while 15.1% exhibited loss beyond the threshold. Non-smokers presented no change in bone loss, while smokers continued to lose bone at an annual rate of 0.17 mm, despite treatment (P <0.005). Likewise, the average percent of sites per patients showing attachment gain beyond the threshold were much greater in non-smokers (13.9%) compared to 9.0% in smokers (P <0.01). Mean probing reduction was 50% greater among non-smokers (0.6 mm) when compared to smokers (0.4 mm), which was also statistically significant (P <0.05). A positive and significant correlation was established between the percentage of sites with AL gain and sites with ACH gain (Rho =0.40; P=0.0001). It is suggested that monitoring sites for AL and ACH gain expressed as changes beyond a selective threshold is an important outcome variable in treatment studies.

A digital subtraction radiography investigation of upper first molar proximal bone density changes in adolescents

The aim of this in vivo study was to investigate the ability of digital subtraction radiography to monitor changes in proximal bone density, adjacent to the upper first molars, in a group of adolescents using the Digora direct digital radiographic system to acquire images. For 57 adolescents, assessments of changes in probing attachment level at the mesio- and disto-buccal surfaces of both upper first molars and proximal crestal bone density using digital subtraction radiography were made. At the conclusion of this 21-month study attachment loss was identified in 34 (17%) of the 204 sites analysed. For sites with attachment loss a mean decrease in bone density equivalent to 5.51 mm3 aluminium (Al) was found compared to 2.96 mm3 Al for those without (p < 0.001). For the 17 subjects with attachment loss a mean equivalent to 4.66 mm3 Al was lost from the crestal bone compared with 2.56 mm3 Al for the 40 subjects without attachment loss (p < 0.01). The correlation between attachment loss and bone density changes was poor for both sites (r = 0.13), p = 0.067) and mean scores for subjects (r = 0.24, p = 0.069). A visual qualitative assessment of bone density change found that 70.6% of sites with attachment loss compared to 62.4% of those without had a decrease in crestal bone density. This study suggests that it is possible to monitor bone density changes in adolescents, with a developing dentition, using digital subtraction radiography. Further, it is suggested that conventional probing assessments of attachment level may underestimate the level of destructive periodontal disease in this age group.

Coordinate production of PGE2 and IL-1 beta in the gingival crevicular fluid of adults with periodontitis: its relationship to alveolar bone loss and disruption by twice daily treatment with ketorolac tromethamine oral rinse

The inflammatory mediators prostaglandin E2 (PGE2) and interleukin-1 beta (IL-1 beta) play critical roles in the inflammatory process leading to alveolar bone and connective tissue loss in periodontal disease. Data from a previously published 6-month clinical study demonstrated that twice daily use of 0.1% ketorolac tromethamine oral rinse prevented alveolar bone loss in adults with periodontitis. We further analyzed data from this study to examine the relationship between PGE2. IL-1 beta and bone loss. Patient mean PGE2 and IL-1 beta levels in gingival crevicular fluid (M-GCF) measured throughout the course of the study were directly compared to the maximum amount of alveolar bone height loss observed at a single study site in each patient. The maximum amount of bone loss measured was chosen for the analysis since the pattern of bone loss was clearly episodic in nature. A statistically significant correlation (r = 0.73, p = 0.001) exists between M-GCF PGE2 concentration and the maximum amount of bone height lost at individual patient study sites. The correlation between M-GCF IL-1 beta concentration and maximum bone height lost is also statistically significant (r = 0.66, p = 0.005). Over the 6-month duration of the study, both PGE2 and IL-1 beta were coordinately expressed in the placebo treatment group as reflected in the significant correlation between M-GCF concentrations of the 2 mediators (r = 0.81, p < 0.001). Treatment of patients with 0.1% ketorolac tromethamine twice daily for 6 months resulted in reductions of PGE2 in GCF and a negligible correlation between M-GCF PGE2 and M-GCF IL-1 beta (r = 0.42, p = 0.088). This lack of a strong association between the 2 mediators in the ketorolac treatment group provides a direct biochemical readout of the anti-inflammatory efficacy of ketorolac tromethamine oral rinse in patients with periodontitis. Further studies are warranted to determine the full diagnostic potential of M-GCF levels of PGE2 and IL-1 beta for predicting risk of alveolar bone loss in patients with periodontitis and monitoring periodontal therapy effectiveness.

The relationship between radiographic and clinical changes in the periodontium

Change in clinical attachment level (CAL) and radiographic change in crestal bone height are often used to assess periodontal breakdown and disease progression. These two variables are also used to monitor the effect of treatment. The purpose of the present longitudinal study was to evaluate the correlation between changes in CAL and alveolar bone loss. Following initial screening, 79 subjects with established periodontitis were monitored quarterly for 1 yr, using a pressure-sensitive automated probe. CAL and relative attachment level (RAL) were recorded at 6 sites for each tooth. Radiographs were obtained at baseline and 1 yr. Crestal bone changes were determined using an image enhancement technique. Mean change in attachment level was 0.16 mm. Similarly, mean proximal bone loss measured radiographically was 0.16 mm. In 6.9% of all the sites, and 13.7% of all pooled interproximal sites, AL loss was in excess of the threshold defined as 2 s.d. of repeated measurements (mean 1.54 mm). Similar percentages of sites (12.9%) had radiographic evidence of proximal bone loss exceeding the threshold (0.55-1.08 mm). A site-based analysis of active sites revealed an overall poor correlation between the 2 variables (kappa value = 0.03) which was the result of a very poor sensitivity (0.16) despite a relatively good specificity (0.81). A patient-based comparison of clinical and radiographical changes revealed an overall kappa value of 0.08, with sensitivity and specificity of 0.51 and 0.56, respectively. However, baseline CAL and crestal bone height showed good correlation (r = 0.73; p = 0.0001). It is suggested that changes in CAL and radiographic bone level progress somewhat independently. Over a short-term period of time they might not follow the same course; however, in the long term, these differences seem to level off. For longitudinal monitoring of disease progression and response to therapy both methods may be needed; while for cross-sectional evaluation and long-term prospective studies, either variable may be used alone.

The relationship of bone loss observed on panoramic radiographs with clinical periodontal screening

The aim of this study was to determine the relationship between bone levels observed on dental panoramic tomographs (DPT) and the WHO/FDI recommended periodontal screening technique: the community periodontal index of treatment needs (CPITN). Computer enhancement and digital analysis were used to improve accuracy and reliability. A total of 199 posterior sextants on DPT radiographs from 50 patients (29 female and 21 male) with a mean age of 42 were examined. A statistically significant relationship was found between CPITN and radiographic measurement from the cemento-enamel junction to the alveolar crestal bone margin (A). The relationship between A and CPITN was found to fit the following equation: square root of A = beta 1 + F, where, F is constant and beta 1 is the coefficient corresponding to the i the codes of CPITN. It was concluded that there was a close correlation between the CPITN screening codes and bone loss as measured on the DPT radiograph.

The use of periodontal probes and radiographs in clinical trials of diagnostic tests

Periodontal probing attachment level measurements and intraoral radiographs are used to assess the level of the clinical attachment and bone support in the diagnosis of periodontitis. Together these physical measurements of tooth support comprise the standard against which new diagnostic tests are compared. Since probing and radiographs provide a measure of the severity of attachment or bone loss at one point in time, serial measurements must be compared to determine whether periodontitis is progressive. Periodontal probing may be performed manually or by using controlled force electronic instruments. The resolution, depending on the instrument, will vary from 1.0 mm to 0.1 mm. Variations in probing force, size and shape of tip, location of tip placement, detection or reference landmarks for attachment level probing, degree of gingival inflammation, and transcription may adversely influence accuracy. Electronic probes offer the advantage of improved resolution, force control, and automatic recording, but the literature is inconsistent about the advantages in terms of repeatability and accuracy. Radiographic assessment of alveolar bone loss may be achieved by visual interpretation, measurement, or digital image analysis. While visual interpretation of unstandardized radiographs is insensitive to changes in bone, standardized radiographs can permit measurement of changes on the order of 0.2 mm when computerized methods are used. Newer techniques such as digital subtraction radiography permit detection of bony changes too small to be seen by the unaided eye and are over 95% sensitive and specific in detecting bony changes less than 10 mg.

Longitudinal study of prognostic factors in established periodontitis patients

Numerous indicators for disease progression have been described in the last decade. The purpose of this study was to examine, longitudinally, a large battery of clinical, microbiological, and immunological indicators, to try to determine whether the presence of one or a combination of these parameters at baseline, would correlate positively with increased attachment and or bone loss (true prognostic factors). Following initial screening, 79 patients with established periodontitis were monitored longitudinally for one year. Whole mouth clinical measurements, plaque gingival and calculus indices, together with pocket depth and attachment level measurements, were repeated every three months. Full mouth radiographic survey, performed at baseline and 12 months, served to determine changes in crestal bone height using an image enhancement technique. Subgingival plaque samples were taken at baseline and every 3 months. Immunofluorescence assays were performed for the a battery of target microorganisms. Serum and GCF samples for IgG subclasses analysis were obtained at each visit and assayed using ELISA techniques. Likewise blood, samples were also drawn at each visit for a quantitative analysis of serum cotinine level. The overall mean attachment loss (AL) and bone loss (BL) were almost identical (0.159 mm and 0.164 mm, respectively). Individual patients variation was large (-0.733 to +1.004 mm). An overall 6.89% of sites were active; individual patients' means ranged from 0-28.9%. Mean pocket depth (PD) showed minimal change over the study period (-0.033 mm) thus suggesting that most if not all the AL was accompained by concomitant gingival recession. Smokers exhibited greater AL and radiographic BL compared to non-smokers. Likewise, patients' cotinine level showed direct correlation with outcomes of progressive periodontal breakdown. Past severity of periodontal involvement, as reflected in the patients baseline PD, AL and crestal bone height, showed good correlation with longitudinal changes in the periodontium. This correlation was higher for crestal BL as the outcome variable, while somewhat smaller for change in AL as the outcome variable. Bacteroides forsythus (Bf.), Prevotella intermedia (Pi.) and Porphyromonas gingivalis (Pg.) were frequently found in these patients. The presence of these microorganisms at baseline was associated with further disease progression. Subjects with mean baseline pocket depth equal or greater than 3.2 mm were at greater risk for future bone loss 1 year later (O.R. 2.97; C.I. 1.02-8.70). Smokers were at significantly greater risk for further attachment loss when compared to non-smokers (O.R. 5.41; C.I. 1.50-19.5). Subjects that harbored B. forsythus at baseline, were at seven times greater risk for increased pocket depth (O.R. 7.84; C.I.1.74-35.3). In conclusion, past periodontal destruction, smoking habits, Bf., Pg., & Pi. are prognostic factors for further periodontal breakdown. When designing clinical trials, or when evaluating epidemiological data, it is most important to balance for these factors. Also, treatment strategies should attempt to eliminate or modify these factors.