An in vitro study of the characteristics of a computer-aided radiographic evaluation (CARE) system for longitudinal assessment of density changes

In recent years, several systems for computerized analysis of radiographs have been introduced, most of which use digital conversion of the image followed by subtraction of consecutive images to assess changes. This paper introduces a computer-based qualitative and quantitative radiographic evaluation system based on the CADIA algorithm. Problems associated with computerized radiographic analysis are discussed and evaluation criteria for this type of system are suggested. These criteria include evaluation of system noise and threshold setting, reproducibility, and establishment of the system working curve (validity). The CARE system noise ranged from a - 10 to + 10 CADIA value and the threshold was set on 13 for all measurements. The reproducibility was high, both for the radiographic technique and for repeated measurements. The working curve was established and showed the system's ability to detect small density changes of 0.048 O.D. which corresponds to 0.27 mm of aluminum thickness or compact bone equivalent. The linear range of the curve was between 0.7 and 1.8 O.D. By controlling the exposure parameters it was possible to work within the linear range of the curve. Based on these evaluation criteria, the CARE system can be used to quantitatively evaluate small density changes on sequential radiographs for early detection of caries and periodontal disease.     

Radiographic evaluation of endodontic therapy and the influence of observer variation

Abstract – In radiographic evaluation of the results of endodontic therapy the development or persistence of periapical radiolucencies often serve as criteria for therapeutic failure. In the present study the influence of inter- and intraexaminer variation on these results was investigated. Three endodontists and three radiologists interpreted periapical conditions and quality of root filling seal in radiographs of 119 endodontically treated roots. Consensus on the pretence of periapical lesion was reached in 27% of cases classified as pathologic. In 6% reports of increased width of the periodontal membrane space accorded. The examiners agreed completely on normal periapical conditions in 37% of the cases. On assessing the quality of root filling seal the opinions of observers differed even more. Complete agreement on cases with adequate and defective seal was reached in 25% and 12%, respectively. For the individual examiner the widened periodontal membrane space was the diagnosis most difficult to reproduce. The present study indicates that the large variation noted among clinical and radiographic studies on the results of endodontic therapy could partly be explained by difficulties in defining and maintaining criteria for radiological evidence of periapical disease.     

A 10-year prospective clinical and radiographic study of one-stage dental implants

OBJECTIVE: The purpose of this prospective study was to evaluate one-stage dental implants clinically and radiographically after 10 years in function. MATERIAL AND METHODS: Twenty-five patients with a total of 68 implants [46 hollow screws (HS) and 22 hollow cylinders (HC)] who previously participated in 5-year prospective clinical study returned for a 10-year follow-up. For each patient, informed consent was obtained, medical and dental history was reviewed and soft and hard tissue conditions were evaluated using the modified plaque index, modified sulcus bleeding index, probing depth, suppuration, attachment level, distance from the implant crown margin to the coronal border of the peri-implant mucosa keratinized mucosa and periapical radiographs to calculate crestal bone-level changes. RESULTS: As expected, the mean crestal bone-level changes were the greatest in the first year following restoration placement, while only minimal changes were noticed in the subsequent years. HC implants showed a statistically significant higher mean crestal bone loss when compared with HS implants at year 10. Gender was also statistically significantly related to the mean crestal bone loss at years 1, 3, 5 and 10, with male subjects exhibiting more bone loss than female subjects. However, age and peri-implant soft tissue parameters showed low levels of correlation with the mean crestal bone-level changes, and proved to be weak predictors for the mean crestal bone loss at years 5 and 10. CONCLUSIONS: This study confirms that the mean crestal bone loss rates of the HS and HC implants are well within the clinically acceptable parameters. In addition, some of the clinical parameters could be used to assess and predict future crestal bone loss.     

The radiographic outcomes of direct pulp-capping procedures performed by dental students: a retrospective study

BACKGROUND: The decision between pulp capping and root canal therapy after pulp exposure is a clinical issue. The aim of the authors' study was to evaluate the outcome of direct pulp-capping procedures performed by dental students. METHODS: The authors followed the treatment outcomes of 193 patients with 204 pulp exposures with direct pulp capping. They determined the outcome of pulp capping radiographically using periapical radiographs taken at least three years after pulp exposure. The outcome was considered as successful if the tooth was present and not associated with periapical radiolucency or root canal treatment; otherwise, the outcome was considered as being a failure. RESULTS: Overall, the success rate of pulp capping was 59.3 percent. The success was associated more with mechanical exposure than with carious exposure (92.2 versus 33.3 percent) (P < .001), more with permanent restoration than with temporary restoration (80.8 versus 47.3 percent) (P < .001) and more with class I occlusal restoration (83.8 percent) than with proximal multiple surface restorations (Class II, 56.1 percent; Class III, 58.8 percent; mesial-occlusal-distal, 28.6 percent) (P = .009). Patients' age, sex, and tooth location and position had no significant effect on the outcome (P > .05). CONCLUSION: The success rate of direct pulp capping was 92.2 percent with mechanical exposure and 33.3 percent with carious exposure. CLINICAL IMPLICATIONS: Direct pulp capping is recommended after mechanical exposure with immediate placement of permanent restoration, while root canal therapy would be the choice of treatment if the exposure was due to caries.     

A 5-year prospective clinical and radiographic study of non-submerged dental implants

Osseointegrated implants as anchors for various prosthetic reconstructions have become a predictable treatment alternative. It was expected that implants required submucosal placement during the healing period for successful tissue integration. However, it has been demonstrated that healing and long-term health of implants could be achieved with equal predictability in a 1-stage, non-submerged approach. This prospective 5-year study not only calculates implant success by life table analysis, but also evaluates the correlation between observed bone level changes with clinical parameters as measured by suppuration, plaque indices, bleeding indices, probing depth, attachment level and mobility. A total of 112 ITI dental implants were inserted in different areas of the jaws. Clinical and radiographic parameters were evaluated annually for 5 years, whereas a portion of the study group for which 6-year evaluations were available were included in the life-table analysis. The overall success rate after 5 years in service was 99.1%, while after 6 years it was reduced to 95.5% due to the fracture of 3 implants in 1 patient. The mean crestal bone loss experienced during the first year was 0.6 mm followed by an annual yearly loss of approximately 0.05 mm. No significant differences could be found between the amount of bone loss measured at each of the yearly follow-up visits. This suggests that statistically the followed implants did not show any radiographically measurable bone loss following the initial period of bone loss associated with implant placement and osseointegration. Low levels of correlation between the individual and cumulative clinical parameters with radiographically measured bone loss suggests that these parameters are of limited clinical value in assessing and predicting future peri-implant bone loss.     

Apical inflammatory root resorption: a correlative radiographic and histological assessment

AIM: To assess the reliability of routine single radiographs in the diagnosis of inflammatory apical root resorption by correlating the radiographic and histological findings. METHODOLOGY: The material comprised serial and step serial sections of plastic-embedded root-apices with attached apical periodontitis lesions that were prepared for a previous study and the diagnostic radiographs. The histological sections of 114 specimens were analysed by light microscopy and categorized into three groups: (i) those without any resorption (0); (ii) those with moderate resorption (+); and (iii) those with severe resorption (+ +). The radiographs were examined by a separate examiner and graded with a similar categorization of no resorption (0); moderate (+); and severe (+ +) apical resorption. RESULTS: Radiographically, 19% of the teeth were diagnosed as having apical inflammatory root resorption, whereas histologically, 81% of the teeth revealed apical inflammatory root resorption. A correlative radiographic and histological assessment (n = 104) revealed a coincidence of diagnosis in 7% of the specimens and noncoincidence of diagnosis in 76% of the specimens. CONCLUSIONS: The results indicate that routine single radiographs are not sufficiently accurate or sensitive to consistently diagnose apical root resorptive defects developing as a consequence of apical periodontitis.     

Magnetic resonance imaging of the temporomandibular joint: a study of inter- and intraobserver agreement

Objective The purpose of this study was to estimate the inter- and intraobserver agreement for interpreting magnetic resonance (MR) images of the temporomandibular joint (TMJ).Methods The study was based on MR images of 30 TMJs. The images were interpreted by seven observers for disk configuration, disk position, joint fluid, bone marrow changes, and diagnosis. The observers were not calibrated. Kappa statistics were used.Results The kappa values were, for interobserver agreement of disk configuration, 0.10; for disk position in the sagittal plane with closed mouth, 0.35; for a combination of closed mouth and open mouth, 0.44; for disk position in the coronal plane, 0.17; for joint fluid, 0.36; for bone marrow changes, 0.01; and for diagnosis, 0.39. Intraobserver agreement was generally higher than interobserver agreement.Conclusion Agreement on disk position in the sagittal plane, on presence and amount of joint fluid, and on diagnosis was fair to moderate. Agreement on disk configuration, on disk position in the coronal plane, and on bone marrow changes was poor.     

Freestanding and tooth-implant connected prostheses in the treatment of partially edentulous patients Part II: An up to 15-years radiographic evaluation

Abstract: A total of 123 patients were followed between January 1983 and July 1998 with 140 tooth‐implant connected prostheses. The age of the patients at prosthesis installation ranged from 20 to 79 years (mean 51.8). 339 (Brånemark^® system) implants were connected to 313 teeth. The loading time ranged from 1.5 to 15 years (mean: 6.5). 123 patients were randomly selected as a control group with freestanding implant‐supported prostheses only. The age of the patients at prosthesis installation ranged from 22 to 78 years (mean 52.3). The loading time for the 329 freestanding (Brånemark^® system) implants ranged from 1.3 to 14.5 years (mean: 6.2). Evolution of the marginal bone stability around the implant in the tooth‐implant connected as well as the freestanding group was studied with respect to the prognosis of the implants. Over the period from 0 to 15 years, there was significantly more marginal bone loss (0.7 mm) in tooth‐implant connected versus freestanding prostheses. No significant difference in marginal bone loss was found between the non‐rigid tooth‐implant connected prostheses versus freestanding prostheses. However, there was a significant difference in marginal bone loss for rigid and multi‐connected tooth‐implant connected prostheses versus freestanding ones. The results of this study indicate that more bone is lost around implants which are rigidly connected to teeth. This suggests that bending load, which is increased in tooth‐implant connected prostheses, might be responsible for this phenomenon. These observations favor the use of freestanding prostheses whenever possible. However, the clinical significance of greater bone loss in rigid versus non‐rigid connections might outweigh the annoying phenomenon of tooth intrusion in the case of non‐rigid tooth connection, when connection is considered.     

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

Abstract 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 extending into the gingival pocket.     

Clinical and radiographic evaluation, following delivery of fixed reconstructions, at GBR treated titanium fixtures

Conditions following incorporation of fixed reconstructions, at endosseous titanium implants augmented at local bony dehiscence and fenestration defects using a bioabsorbable Resolut® membrane were studied in 7 patients. Fixture stability, radiographic marginal bone levels and peri‐implant soft tissue status were evaluated at 2 1 membrane treated and 17 control fixtures (installed in regions of adequate bone volume), following a 2‐year period of functional loading. Prosthetic reconstructions were removed and clinical examination and Periotest values revealed that all fixtures were stable. All peri‐implant soft tissues were clinically healthy. The mean probing depths at buccal sites for fixtures with original dehiscence ( n =10) and fenestration ( n =11) defects were 1.6 ± 0.7 mm and 1.2 ± 0.4 mm respectively. The control fixture group had a mean buccal probing depth of 1.4 ± 0.6 mm. At abutment connection radiograph membrane treated fixtures had significantly lower marginal bone levels than control fixtures, indicating that optimal bone regeneration was not achieved at all defects. Mean radiographic bone loss 23–7 months following delivery of fixed reconstructions for original dehiscence and fenestration defect fixtures was 0.7 ± 0.8 mm and 0.8 ± 0.6 mm respectively at mesial surfaces, and 0.8 ± 0.7 mm and 0.6 ± 0.5 mm at distal surfaces. In the control fixture group a mean loss of 0.7 ± 0.5 mm at mesial surfaces and 0.5 ± 0.4 mm at distal surfaces was found. Results showed no significant difference in the rate of bone loss following functional loading between membrane treated and control fixtures.     

Bone Histomorphometry using interactive image analysis. A methodological study with application on the human temporomandibular joint

The aim was to develop a reproducible method for bone histomorphometry with the aid of a computerized image analysis program, and to examine the variation when assessing the total and the trabecular bone volume. Histologic sections of 18 temporomandibular joint autopsy specimens were read interactively using a cursor. The two parameters total bone volume and trabecular bone volume, of the condyle and the temporal component respectively, were estimated 2 × by 1 observer using 3 different threshold settings: an automatic, a semiautomatic and a manual technique. The threshold was based on the gray-scale distribution of the image. 2 observers read the same sections with the aid of the semi-automatic technique. The intra-observer variation expressed as coefficient of variation ranged between 1.9% and 7.1% for the different parameters, when the automatic threshold setting technique was employed, and between 2.8% and 8.7% with the semi-automatic technique. The manual technique resulted in a high intra-observer variation with a coefficient of variation between 5.2% and 19.9%. There was a systematic difference between the estimates of the 2 observers. In general, intra- and inter-observer variation was higher in the temporal component than in the condyle. The inter-section variation was moderate, the coefficient of variation ranging from 3.8% to 11.1%. The automatic and semi-automatic techniques resulted in comparable intra-observer variation, with a lower bias in the estimates of the semi-automatic technique. By letting one observer apply the semi-automatic technique, it was possible to achieve fast and reproducible analysis of the total and trabecular bone volume.     

Impact of chronic oral mucosal disease on daily life: preliminary observations from a qualitative study

Oral Diseases (2011) 17 , 265–269 Objective: To explore the experience of daily life of persons with chronic oral mucosal conditions. Methods: Purposive sampling was used to recruit patients from the Oral Medicine Unit of Cork University Dental School and Hospital. An experienced independent facilitator convened the focus groups and conducted individual interviews in a non clinical setting. Focus groups were mixed with regard to gender, age, chronic oral mucosal condition, time since diagnosis and severity. A total of 24 patients took part, including patients with oral lichen planus, mucous membrane pemphigoid, pemphigus vulgaris, recurrent aphthous stomatitis and orofacial granulomatosis. Results: Analysis of the interviews revealed that patient views could be divided into the following themes – biopsychosocial issues, treatment limitations and side effects, unpredictability of the conditions and the potential for malignant transformation and issues for the healthcare professionals. Conclusion: Chronic oral mucosal conditions impact upon the experience of daily life of patients in a variety of areas from physical health and functioning, to concerns about their future. The role of the oral medicine practitioner in treating patients with chronic oral mucosal diseases extends beyond active management and symptomatic relief to the management of all aspects of these conditions that impact upon their daily lives.     

Asymptomatic radiopaque lesions of the jaws: a radiographic study using cone-beam computed tomography

Panoramic radiography and cone-beam computed tomography (CT) were used to analyze asymptomatic radiopaque lesions in the jaw bones and determine the diagnostic relevance of the lesions based on their relationships to teeth and site of origin. One hundred radiopaque lesions detected between 1998 and 2002 were examined by both panoramic radiography and cone-beam CT. On the basis of panoramic radiographs, the region was classified as periapical, body, or edentulous, and the site was classified as molar or premolar. Follow-up data from medical records were available for only 36 of these cases. The study protocol for simultaneous use of cone-beam CT was approved by the ethics review board of our institution. A large majority of radiopaque lesions were observed in premolar and molar sites of the mandible; 60% of lesions were periapical, 24% were in the body, and 16% were in the edentulous region. An interesting type of radiopaque lesion, which we named a pearl shell structure (PSS), was observed on cone-beam CT in 34 of the 100 lesions. The PSS is a distinctive structure, and this finding on cone-beam CT likely represents the start of bone formation before bone sclerosis.     

Effect of microthread on the maintenance of marginal bone level: a 3-year prospective study

OBJECTIVES: The purpose of the present study was to evaluate the long-term effect of the microthread on the maintenance of marginal bone level. MATERIAL AND METHODS: Seventeen patients were selected and two types of Astra Tech implants were installed, with the Microthread on the coronal portion of the fixture [Astra Tech Single Tooth Implant (ST)] or without the Microthread [Astra Tech TiOblast Implant (TB)]. ST and TB were installed adjacent to each other within the same partially edentulous sites and marginal bone loss was evaluated by radiographic image. The marginal bone-level alteration of the each fixture after prosthesis insertion was analyzed. RESULTS: The marginal bone loss of ST and TB differed significantly during the observation period (P<0.01). Marginal bone levels of both ST and TB were stabilized after 1 year of lading. CONCLUSIONS: The Microthread might have an effect in maintaining the marginal bone loss against loading.     

The prognostic value of several periodontal factors measured as radiographic bone level variation: a 10-year retrospective multilevel analysis of treated and maintained periodontal patients

BACKGROUND: Assigning a prognosis to a periodontal patient is one of the greatest challenges in clinical practice. Many different factors can affect the result of periodontal therapy. The purpose of this study was to evaluate the prognostic value of some clinical, genetic, and radiographic variables in predicting bone level variation in periodontal patients (aged 40 to 60) treated and maintained for 10 years. METHODS: Sixty consecutive non-smoking patients (mean age 46.77 +/- 4.96) with moderate to severe chronic periodontitis were treated with scaling and root planing (SRP). Some patients also underwent additional surgical treatments. All patients were maintained in the same private practice for 10 years. At baseline (T0) and at least 10 years later (T2), the following clinical variables were evaluated: probing depth (PD), tooth mobility (TM), presence of prosthetic restorations (PR), and molar teeth (MT). In addition, radiographic measurements were taken of the mesial and distal distances from the cemento-enamel junction (CEJ) to the bottom of the defect (BD), to the bone crest (BC), and to the root apex (RA). At T2, a genetic test to determine the IL-1 genotype and genetic susceptibility for severe periodontal disease was performed for all 60 patients. Based on the results of this assay, the patients were categorized as IL-1 genotype positive (G+) or negative (G-). The differences between the bone levels measured at T0 and T2 (ABD), indicating the bone level variation, was used as the outcome variable. Different predictor variables were then tested using a 3-level statistical model (multilevel statistical analysis; patient, tooth, and site level). At the patient level these were: age, gender, and interaction between mean bone loss and the IL-1 genotype (mean CEJ-BD(T0) x IL-1 genotype). At the tooth level the variables were: TM(T0), PR(T0), MT(T0); and at the site level the evaluated factors were: the infrabony component of the defect (CEJ-BD(T0) - CEJ-BC(T0), PD(T0), bone level (CEJ-BD(T0)), and the residual supporting bone (BD-RA(T0)). RESULTS: Among the considered predictor parameters, the following were significantly associated with the outcome variable: 1) mean CEJ-BD(T0) x IL-1 genotype (P = 0.0019); 2) TM(T0) (P < 0.0000); 3) CEJ-BD(T0) (P < 0.0000); 4) CEJ-BD(T0) - CEJ-BC(T0) (P < 0.0000); 5) PD(T0) (P = 0.0010). Deeper probing depths at a site and tooth mobility at baseline were associated with worst prognosis. Greater CEJ-BD(T0) distance and infrabony component at a site at baseline were associated with a better prognosis. The interaction between mean CEJ-BD measurement at baseline and IL-1 genotype was significantly associated both with a good or a poor prognosis. The other parameters evaluated - age, gender, presence of molars and prosthetic restorations, and residual supporting bone - were not significantly associated with bone level variation. CONCLUSIONS: Within the scope of this study design, many traditional prognostic factors were ineffective in predicting future bone level variation and therefore were of no prognostic value. Conversely, a few specific factors at each level emerged as valuable prognostic factors. At the patient level, the prognostic factor was initial mean bone level in conjunction with a positive IL-1 genotype. At the tooth level, the prognostic factor was tooth mobility. At the site level, the significant prognostic factors were initial bone level at a site, the infrabony component of a defect, and initial probing depth at a site. The use of these factors may be of value to clinicians as predictors of bone level variation when assigning a prognosis to a patient, a tooth, or a site.