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Background: The aim of this study was to determine if image enhancement improves a clinician's ability to identify the presence of calculus on digital radiographs., Methods: Seventy-one hopeless teeth were collected from 34 patients. Teeth were stained with 1% methylene blue, the largest interproximal calculus deposit was scored, and photographs of each interproximal root surface were taken. The surface area of calculus deposit was determined as a percentage of the total interproximal root surface area. Digital radiographs of teeth taken before extraction were modified using the following enhancements: auto-contrast, emboss, invert, and sharpen. Radiographic presence of calculus was determined by two examiners. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for each examiner and enhancement. A receiver operating characteristic curve was used to compare differences between the image enhancements in the detection of dental calculus. The kappa statistic was used to compare ratings between examiners., Results: None of the enhanced images were statistically superior to original images in identifying radiographic calculus (P > 0.05). The average sensitivity of digital radiography was 50%, average specificity was 82.2%, PPV was 94%, and NPV 23.2%. A threshold of >30% of interproximal root surface covered with calculus and increasing size of deposits were associated with improved detection (P < 0.05)., Conclusions: Digital enhancements do not significantly improve radiographic detection of dental calculus. As area of calculus on the root surface and size of calculus deposits increased, sensitivity of detection also increased., (© 2020 American Academy of Periodontology.)

Objective: The aim of this in vitro study was to evaluate the ability of optical coherence tomography (OCT) to display calculus on root surfaces., Material and Methods: Ten teeth with calculus on the root surface were embedded in resin, omitting the root surface. A region of interest (ROI) was marked by small drill holes coronally and apically of the calculus and imaged by spectral-domain optical coherence tomography ([SD OCT], Telesto SP5, centre wavelength 1310 nm) and light microscopy (LM). To evaluate the impact of different fluids on calculus visualisation, using OCT, root surfaces were covered by a layer of NaCl and blood and displayed by OCT. Subsequently, teeth were completely covered with resin and sectioned for histological evaluation. Within the ROI, lengths of root surface and calculus were measured by LM and OCT, and the ratio [%] was calculated. In addition, at three sites of each ROI, agreement of presence and length of calculus was evaluated. Both methods were compared using Pearson's correlation., Results: Regarding the presence of calculus, agreement between LM and OCT was strong (κ i  = 0.783, p = 0.033), and measurements regarding the length of the calculus were strongly correlated (r i >0.906; p i <0.001). However, the values differed for dry (p = 0.023) and NaCl-covered root surfaces (p = 0.035)., Conclusion: Calculus on the root surface can be displayed by SD-OCT, which therefore may be suited as imaging technology for subgingival calculus in periodontal pockets., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The identification of root caries and calculus on tooth roots is of increasing importance with our aging population. Exposed root surfaces are often impacted by erosion, abrasion, calculus and staining which can make the identification and management of caries challenging. Identification of dental calculus on root surfaces and verification of its removal is also important for patient education and to decrease susceptibility to caries and periodontal disease. The objective of this study was to determine how the contrast of root caries lesions and dental calculus varies with wavelength in the visible to near-infrared. The contrast of suspected root caries lesions and dental calculus on 30 extracted teeth was measured using cross-polarization reflectance measurements at wavelengths from 400 to 2350 nm. Significantly higher (P < 0.05) lesion contrast was measured at wavelengths greater than 1460 nm. Stains interfered significantly at wavelengths less than 850 nm yielding non-diagnostic contrast for root caries lesions. We postulate that the high absorption of water at longer wavelengths reduced the light scattering from the surrounding and underlying normal dentin, thus increasing the lesion contrast. This study indicates that wavelengths beyond 1400 nm are advantageous for imaging calculus and caries lesions on root surfaces due to the high contrast and lack of interference from stain., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

This study evaluated the effectiveness of swept-source optical coherence tomography (ss-OCT) for detecting calculus and root cementum during periodontal therapy. Optical coherence tomography (OCT) images were taken before and after removal of subgingival calculus from extracted teeth and compared with non-decalcified histological sections. Porcine gingival sheets of various thicknesses were applied to the root surfaces of extracted teeth with calculus and OCT images were taken. OCT images were also taken before and after scaling and root planing (SRP) in human patients. In vitro, calculus was clearly detected as a white-gray amorphous structure on the root surface, which disappeared after removal. Cementum was identified as a thin, dark-gray layer. The calculus could not be clearly observed when soft tissues were present on the root surface. Clinically, supragingival calculus and cementum could be detected clearly with OCT, and subgingival calculus in the buccal cervical area of the anterior and premolar teeth was identified, which disappeared after SRP. Digital processing of the original OCT images was useful for clarifying the calculus. In conclusion, ss-OCT showed potential as a periodontal diagnostic tool for detecting cementum and subgingival calculus, although the practical applications of subgingival imaging remain limited.

Periodontal disease is a common disease of dogs and is initiated by the buildup of plaque on the tooth surface. As plaque matures, it becomes mineralized to form calculus, which although not directly involved in the etiology of periodontal disease, provides an irregular surface to which plaque can adhere. Evaluation of the quantity of plaque and calculus on dogs' teeth is therefore essential to enable the efficacy of products, designed to prevent or retard plaque and calculus accumulation, to be evaluated. The objective of this study was to determine whether quantitative light-induced fluorescence (QLF TM ) is a suitable tool to quantify the amount of calculus on the buccal surface of dogs' teeth following the removal of disclosed plaque by tooth brushing. The amount of calculus on the teeth of 26 miniature schnauzers was measured, using QLF and a calculus index method (Warrick-Gorrel), during a 28-day phase crossover study comparing feeding a daily dental chew versus providing no daily chew. Quantification of calculus using the Warrick-Gorrel method showed a 43.8% reduction in calculus buildup, with 95% confidence interval of 27.3 to 60.3 ( P < .001). With QLF, the percentage reduction in calculus accumulation was 65.8% (58.1-73.4, P < .001). A retrospective sample size analysis showed that fewer dogs were required for QLF analysis compared to the Warrick-Gorrel method. This study demonstrated that QLF is a sensitive and precise method for quantification of calculus on dogs' teeth. It removes the subjective element of human examiners and has greater accuracy and reduced variability through the continuous nature of the data.

Background: Periodontitis is a multifactorial and infectious disease that may result in significant debilitation. The aim of this study is to exploit two optical coherence tomography (OCT) systems operating in the Fourier domain at different wavelengths, 930 and 1,325 nm, for structural analysis of periodontal tissue in porcine jaws., Methods: Five fresh porcine jaws were sectioned and stored in formalin before OCT analysis. Two- and three-dimensional OCT images of the tooth/gingiva interface were performed, and measurements of the gingival structures were obtained. The 930-nm OCT system operates in the spectral domain, whereas the 1,325-nm system is a swept-source model. Stereomicroscope images, the gold standard, were used for direct comparison., Results: Through image analysis, it is possible to identify the free gingiva and the attached gingiva, the calculus deposition over tooth surfaces, and the subgingival calculus that enables the enlargement of the gingival sulcus. In addition, the gingival thickness and the gingival sulcus depth can be non-invasively measured, varying from 0.8 to 4 mm., Conclusions: Regarding the ability of the two OCT systems to visualize periodontal structures, the system operating at 1,325 nm shows a better performance, owing to a longer central wavelength that allows deeper tissue penetration. The results with the system at 930 nm can also be used, but some features could not be observed due to its lower penetration depth in the tissue.

The effective treatment of periodontitis involves the detection and removal of subgingival dental calculus. However, subgingival calculus is more difficult to detect than supragingival calculus because it is firmly attached to root surfaces within periodontal pockets. To achieve a smooth root surface, clinicians often remove excessive amounts of root structure because of decreased visibility. In addition, enamel pearl, a rare type of ectopic enamel formation on the root surface, can easily be confused with dental calculus in the subgingival environment. In this study, we developed a fiber-probe swept-source optical coherence tomography (SSOCT) technique and combined it with the quantitative measurement of an optical parameter [standard deviation (SD) of the optical coherence tomography (OCT) intensity] to differentiate subgingival calculus from sound enamel, including enamel pearl. Two-dimensional circumferential images were constructed by rotating the miniprobe (0.9 mm diameter) while acquiring image lines, and the adjacent lines in each rotation were stacked to generate a three-dimensional volume. In OCT images, compared to sound enamel and enamel pearls, dental calculus showed significant differences (P<0.001) in SD values. Finally, the receiver operating characteristic curve had a high capacity (area under the curve=0.934) for discriminating between healthy regions (including enamel pearl) and dental calculus.

Objectives: To assess the intra-examiner reliability of recordings of subgingival calculus detected using an ultrasonic device, and to investigate the influence of subject-, tooth- and site-level factors on the reliability of these subgingival calculus recordings., Materials and Methods: On two occasions, within a 1-week interval, 147 adult periodontitis patients received a full-mouth clinical periodontal examination by a single trained examiner. Duplicate subgingival calculus recordings, in six sites per tooth, were obtained using an ultrasonic device for calculus detection and removal., Results: Agreement was observed in 65 % of the 22,584 duplicate subgingival calculus recordings, ranging 45 % to 83 % according to subject. Using hierarchical modeling, disagreements in the subgingival calculus duplicate recordings were more likely in all other sites than the mid-buccal, and in sites harboring supragingival calculus. Disagreements were less likely in sites with PD ≥  4 mm and with furcation involvement  ≥  degree 2. Bleeding on probing or suppuration did not influence the reliability of subgingival calculus. At the subject-level, disagreements were less likely in patients presenting with the highest and lowest extent categories of the covariate subgingival calculus., Conclusions and Clinical Relevance: The reliability of subgingival calculus recordings using the ultrasound technology is reasonable. The results of the present study suggest that the reliability of subgingival calculus recordings is not influenced by the presence of inflammation. Moreover, subgingival calculus can be more reliably detected using the ultrasound device at sites with higher need for periodontal therapy, i.e., sites presenting with deep pockets and premolars and molars with furcation involvement.

Unlabelled: The AIM of this study was to evaluate the usefulness of 40 MHz periodontal ultrasonography in the assessment of gingival inflammation, following professional teeth cleaning., Material and Methods: The study was performed on 18 teeth without restorations having subgingival calculus (upper and lower premolars and frontal teeth). After the clinical exam the Gingival Index and the Sulcus Bleeding Index were calculated. Then a 40MHz transducer (ULTRASONIX SonoTouch device) was used to obtain longitudinal sections in the frontal plane. Three measurements were performed: alveolar crest - cementum-enamel junction distance (ACJ), gingival height (GH), and gingival width (GW). Professional cleaning was performed by ultrasound scaling (SatelecP5 booster, France) and airflow (NSK, Japan). Two and seven days after the first evaluation, ultrasonographic and clinical examinations were repeated., Results: Two days after the treatment the median value of the ACJ, was 2.70 (2.38; 2.95) mm, whereas 7 days after treatment it was 2.55 (2.45; 3.01) mm. The intraclass correlation coefficient for ACJ measurement was 98.8 (p<0.001).The values obtained measuring GH [3.84(3.44; 4.27) mm vs. 3.52 (3.00; 3.76) mm] and GW [(1.81 (1.65; 1.95) mm vs.1.62 (1.40; 1.95) mm) had statistically significant differences between the 2nd and 7th day., Conclusions: Periodontal ultrasonography is a highly precise and reproducible imagistic method, with which bone resorption, gingival inflammation as well as the presence or absence of subgingival calculus can be assessed.

Epidemiological studies have implicated dental calculus as an ideal substrate for subgingival microbial colonization. Therefore, the main objective of periodontal therapy is to eliminate the microbial biofilm along with the calculus deposits from the root surface by root surface debridement. Over the past years, a large number of clinical and laboratory studies have been conducted to evaluate the efficacy of calculus removal by various methods. None of these conventional methods or devices was effective in completely eliminating all the calculus from the diseased root surfaces. In this context, a number of newer technologies have been developed to identify and selectively remove the dental calculus. Regarding this fact, the present article highlights a critical review of these devices based on published clinical and experimental data.

Purpose: Sparse reports on the composition of mineralized deposits forming in the child's oral cavity generally reveal their lower degree of mineralization. As reports on the formation of dental calculus in children are incomplete, we decided to study some conditions in which this process takes place. The aim of the study was to determine whether fluorine is present in supragingival dental calculus. We enrolled 12-year-old children (17 girls, 11 boys) living in a large city., Results: X-ray microanalysis of dental calculus revealed the presence of carbon, oxygen, calcium, phosphorus, sodium, magnesium, potassium, sulphur, chlorine, silicon, and fluorine. Chemical analysis of 10 sites on each specimen showed large variations as to the number of elements found and their content. Fluorine was present in one specimen only (3.6%) at a very high concentration of 10.27%+/-1.27 (w/w). Chemical composition of mineralized dental deposits shows marked individual variability and the presence of fluorine is not a constant finding.

Five examples of radiographic oddities, culled from the records of private dental practitioners, are presented. Two cases feature radiographic manifestations of systemic disease, and three cases display anomalous oral findings. Each illustration is furnished with a short narrative and interpretation.

Unlabelled: Radiographs are commonly used in the diagnosis of periodontal diseases. They can be used to assess bone loss and the pattern of loss as well as in the identification of other periodontally relevant features, such as overhanging restoration margins, calculus deposits and furcation lesions. Horizontal and vertical bitewings, panoramic radiographs and periapicals can be used for periodontal assessment. Referral (selection) criteria based on clinical signs can assist the decision of the radiographs to use. All exposures must be made in accordance with the Ionizing Radiation (Medical Examination) Regulations 2000 and each exposure justified., Clinical Relevance: Following a clinical examination, optimum selection of radiographs can assist in the assessment of patients with periodontal diseases.

Objective: A radiographic investigation into the relationship between tobacco smoking and subgingival dental calculus was conducted in an adult population, including 48 current smokers, 57 former smokers, and 125 non-smokers., Material and Methods: Assessment of subgingival calculus was based on a full set of radiographs. Mesial and distal root surfaces were assessed as to presence or absence of radiopaque deposits apical to the cemento-enamel junction. The severity of subgingival calculus deposition, labeled subgingival calculus load, was estimated from both the total number and the proportion of proximal sites affected., Results: The overall prevalence of individuals exhibiting at least one subgingival calculus positive site was 43%, ranging from 15% in age stratum 20-34 years to 72% in age stratum 50-69 years. The prevalence among current smokers, former smokers, and non-smokers was 71%, 53%, and 28%, respectively. The differences between smoking groups were statistically significant (p<0.001). The mean subgingival calculus load of current smokers, former smokers, and non-smokers was 3.4, 1.2, and 0.6 affected sites per person, respectively, or expressed as mean proportions, 6.2%, 2.4%, and 1.1%, respectively. The association between smoking and subgingival calculus load was statistically significant (p<0.001). The subgingival calculus load increased with increasing smoking exposure, suggesting a dose-response relationship., Conclusion: The present observations in dentally aware adults indicate a strong and independent impact of tobacco smoking on subgingival calculus deposition., (Copyright Blackwell Munksgaard, 2004.)

The aim of this study was to determine the association between the quantity of subgingival calculus and the following factors: type and severity of periodontal disease, age, gender and tobacco consumption. A sample of 622 periodontal patients was studied. The radiographically detectable subgingival calculus in proximal root surfaces was recorded in periapical radiographs, considering the number of surfaces without calculus and the number of surfaces exhibiting deposits equal or greater than I mm. The association between the subgingival calculus and the factors under study was analyzed by distinct non-parametric tests. A statistically significant association was found between the absence/presence of subgingival calculus and the type and severity of periodontal disease (p<0.001), tobacco consumption (p=0.0049) and age (p<0.001). The quantity of radiographically-detectable subgingival calculus increased with increasing age and severity of the disease. However, the reverse association was found in smokers, which presented more surfaces free of calculus (p=0.0377) and less surfaces exhibiting deposits equal or greater than 1 mm. The amount of subgingival calculus decreased as the quantity of tobacco consumed increased (p=0.0129), and such differences were more significant in those smoker patients with severe periodontitis (p= 0.0065). An explanation is presented to justify these latter findings, since most literature supports that the presence of calculus is higher in smokers. According to the results of this study, more radiographically-detectable subgingival calculus in proximal root surfaces was found with increasing severity of the disease, with increasing age and with the absence of tobacco consumption.

Objective: The purpose of this study was to establish an optimum radiographic examination regimen for patients undergoing bone marrow transplantation. Two radiographic examinations were compared: the panoramic radiograph and the full mouth series of radiographs., Study Design: A prospective analysis of 65 consecutive patients undergoing bone marrow transplantation was undertaken. All patients were examined through use of both panoramic and full mouth series intraoral radiographs, including bitewings. Significant findings were recorded and compared by means of paired t test analysis for parametric data, such as caries, periapical inflammation and subgingival calculus, and by means of McNemar's test for nonparametric data, such as the presence or absence of severe periodontal disease., Results: Acquired findings, such as caries, periodontal disease, and clinically significant faulty restorations, were detected more frequently from the full mouth series (P < .05). There was no significant difference in the detection of periapical pathosis. In 8 of 65 patients, clinically significant information, such as evidence of impacted wisdom teeth, neoplasms, and multiple myeloma, was better detected from the panoramic radiographs., Conclusions: The results suggest a combination of both modalities as the optimum means of radiologic survey in this "high-risk" patient 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.

The pattern and distribution of periodontitis were investigated in 162 randomly selected dogs available for necropsy in veterinary practice. There were 82 males and 80 females of 50 different breeds (150 dogs were pure-bred and 12 were mongrels, aged between 7 months and 14 yr. Presence of periodontitis was determined by assessment of alveolar bone loss on radiographs of the skulls and jaws. Periodontitis occurred frequently with increasing age, although the prevalence varied markedly among and within different breeds. Of the breeds most represented in the sample, periodontitis was most frequently seen in poodles and dachshunds but was rarely recognized in German shepherd dogs. Regardless of age, the vast majority of the dogs displayed either one or both of two different radiographic patterns of alveolar bone loss. One pattern was characterized by slight, horizontal alveolar bone loss involving interradicular and interdental areas. The other pattern was one of predominantly crater-like, or narrow, vertical bone defects which, when advanced, often extended around a single root or tooth to surround the root apices. The two types of patterns did not seem to be breed-dependent. The posterior maxillary and mandibular premolars and molars were the most frequently affected teeth. Alveolar bone loss was most severe in the maxilla, while corresponding bone loss in the mandible was more often related to increasing age.

In the present study the periodontal condition of a group of adopted 6-17 year-old children of Asian origin living in Sweden was compared with that of age- and sex matched Sweden children. Thirty-one Asian children and 31 Swedish children participated. Data on general health for all the children and on age at arrival for the Asian children was collected by interview. A clinical examination included recording of presence of plaque, supragingival calculus, bleeding on probing, probing depth, and caries. Radiographs were used to determine marginal bone loss (distance between the cemento-enamel junction and the marginal bone level > 2 mm), proximal calculus, and proximal caries. In addition, previously taken and filed radiographs of the primary dentition of the older children and current radiographs of the younger children with primary teeth were analysed to determine the prevalence of bone loss and calculus. The children of Asian origin showed a significantly higher number of surfaces with plaque and bleeding on probing. No significant differences were noted in the number of individuals with probing depths > or = 4 mm, supragingival calculus, or radiographic calculus. Three of the Asian and none of the Swedish children displayed radiographic bone loss. The retrospective analysis of all available radiographs from the primary dentition showed that 9 of 29 (31%) Asian children and 2 of 29 (7%) Swedish children had experienced bone loss in primary teeth.

The mandibles of 81 randomly selected cats were examined clinically and radiographically for dental calculus, periodontitis, odontoclastic resorptive lesions (FORL) and osteoporosis. Extent of calculus increased with increasing age. Prevalence and severity of periodontitis and FORL increased with increasing age. Osteoclastic resorption and/or osteoporosis increased with age, advancing from rostral to caudal in cortical bone. No significant correlation of periodontitis with FORL could be demonstrated.

The aim of the present study was to compare the periodontal health in Vietnamese immigrant children in Sweden with that of native Swedish children. The study groups consisted of 42 6-17-year-old Vietnamese children and 42 age- and sex-matched Swedish children. Information on systemic health was obtained by interview. Clinical examination included recordings of dental plaque, supragingival calculus, bleeding on probing, probing depth, clinical attachment loss and caries. Radiographs were evaluated for presence of marginal bone loss, proximal calculus and proximal caries. In addition, previously obtained and filed radiographs were used as a supplement in order to evaluate if the children at any time point during the ages 4-11 years had experienced proximal calculus or bone loss in the primary dentition. The Vietnamese children showed significantly higher number of sites with bleeding on probing and with probing depths > or = 4 mm. Radiographic calculus was found in 55% of the Vietnamese and in 2% of the Swedish children. 5 Vietnamese children and 1 Swedish child showed periodontal bone loss at the time of examination. In all children except 1, the bone loss was confined to primary teeth. The retrospective analysis of available radiographs from the primary dentition showed that 28% of the Vietnamese children and 5% of the Swedish children had experienced bone loss in their primary teeth during the ages 4-11 years.(ABSTRACT TRUNCATED AT 250 WORDS)

The diagnostic performance of the detailed narrow-beam (DNB) technique of the Scanora multimodal X-ray system was compared with periapical radiography for detecting periodontal pathology. In total, 253 sites in 133 patients were examined. Receiver operating characteristics (ROC) of both imaging modalities were analyzed in relation to the ratings of five observers for the whole dentition, three dental regions and five types of periodontal lesion. ROC analysis demonstrated that the overall diagnostic performance of DNB radiography was better (P < 0.05) than that of periapical radiography. DNB radiography was significantly superior (P < 0.01) for detecting marginal widening of periodontal membrane space, but there was no significant difference between the two techniques for crestal erosion, vertical bone loss, furcation involvement or calculus. The regional differences found in overall diagnostic performance of the two imaging modalities were not significant. The sensitivity for periapical radiography was 71% and for DNB radiography 85%, and the specificities 82% and 81% respectively. It is concluded that DNB radiography is a good radiographic examination for periodontal disease, and an acceptable alternative to periapical radiography.

118 patients with juvenile periodontitis (JP), diagnosed when the patients were 13-19 years old, were studied retrospectively with respect to radiographic marginal bone loss in the primary dentition, experienced when the patients were 5-12 years old. 168 other 13-19 year old patients without any signs of bone loss in the permanent teeth were used as a reference group. The JP patients were classified into 2 groups according to the number of sites with bone loss in the permanent dentition: JP group I having 1 site with bone loss (n = 45) and JP group II having > or = 2 sites with bone loss (n = 73). It was found that 35 patients (52%) of JP group II displayed 1 or more sites with bone loss in the primary dentition during the age of 5-12 years. The corresponding numbers for JP group I and the reference group were 9 (20%) and 8 (5%) respectively. These findings indicate that juvenile periodontitis, at least in some individuals, may have its onset already in the primary dentition.

Dental panoramic tomographs (DPTs) were taken consecutively of 500 patients referred to a specialist periodontal department by general dental practitioners in order to assist in the diagnosis of the severity of the periodontal disease. Analysis of these DPTs showed 316 (63.2%) of these patients to have some form of dental abnormality unrelated to periodontal disease. The DPT was shown to be a valuable screening technique for clinical practice.

A method is described to produce radiographs of thin sections of human teeth and periodontal structures. These high resolution contact x-rays allow for visualization of the microscopic details of the mineralized components of these tissues in a dimension heretofore not examined. Twenty-five blocks of human jaws containing teeth affected by periodontal disease were obtained from cadavers. Sagittal, transverse and cross-sectional serial slices were cut using a rotary instrument (1500 rpm) with a water-cooled 3-inch jewelers slot saw. Five hundred-micron sections were made of jaw specimens containing 2 or 3 teeth. The radiographs were taken with a Faxitron low voltage x-ray machine on Kodak-Ortho, Type 3 film. Films were exposed at a distance of 12 inches from the x-ray source at 35 kVp and 1.0 mA for 3 minutes with the specimen in direct contact with the film. Spatial representation of the internal structure of the alveolar bone was obtained using this technique and the detailed anatomy of the vascular channels within the cancellous and cortical compartments of the jaws was studied. Mineralization patterns of plaque and calculus, calcifications in the periodontal ligament, pulp calcifications, accessory root canals, caries and detailed structural changes in the enamel and cementum were also viewed on these films with the aid of microscopy. Magnifications of up to 30 times were used without excessive image distortion resulting from film grain.

Panoramic periapical anterior and posterior bitewing radiographic, mirror-explorer, and transillumination clinical examinations were performed on 300 patients. Various combinations of the radiographic and clinical examination techniques were compared in terms of their ability to diagnose caries, alveolar bone loss, calculus, periapical bone lesions, impacted teeth, root tips, and miscellaneous conditions. A mirror-explorer clinical examination with panoramic and posterior bitewing radiographs and either anterior bitewing radiographs or transillumination proved to be as efficient in the initial examination of patients as the mirror-explorer clinical examination with periapical and posterior bitewing radiographs.

An experimental intraoral dental xeroradiographic system was evaluated for its ability to image structures important in periodontal radiographic interpretation. On consenting dental patients, similar x-ray projections were made on (1) conventional film radiography and (2) experimental dental xeroradiographs. The resultant images were compared visually. In all categories examined the information provided by xeroradiography was either equal to or greater than that provided by conventional film radiographs. Intraoral dental xeroradiography appears to be a highly accurate, low-radiation, rapid, and convenient alternative to conventional intraoral radiography.

To determine the sensitivity and specificity of the radiographic detection of calculus, 275 proximal tooth surfaces from 18 patients were evaluated. Standardized periapical radiographs obtained before extraction were coded, batch processed, and evaluated independently by two investigators under optimum viewing conditions. After extraction, the teeth were photographed and evaluated both microscopically and by planimetry on 40 X linear projections. Evaluation of calculus by conventional radiography showed low sensitivity: radiographic deposits were detected on only 44% of surfaces that demonstrated calculus microscopically. Specificity was high and the rate of false positives was only 7.5%. Detection of calculus was influenced by the thickness of calculus, the percentage of root surface occupied by calculus, and by tooth type; but not by attachment loss, probing depth, proximal surface, or arch location. These results show that present radiographic techniques are not appropriate for detecting calculus on root surfaces.