Arthur D. Goren

Doxycycline Effects on Serum Bone Biomarkers in Post-menopausal Women

We previously demonstrated that subantimicrobial-dose-doxycycline (SDD) treatment of post-menopausal osteopenic women significantly reduced periodontal disease progression, and biomarkers of collagen destruction and bone resorption locally in periodontal pockets, in a double-blind placebo-controlled clinical trial. We now hypothesize that SDD may also improve biomarkers of bone loss systemically in the same women, consistent with previous studies on tetracyclines (e.g., doxycycline) in organ culture and animal models of bone-deficiency disease. 128 post-menopausal osteopenic women with chronic periodontitis randomly received SDD or placebo tablets daily for 2 years adjunctive to periodontal maintenance therapy every 3-4 months. Blood was collected at baseline and at one- and two-year appointments, and sera were analyzed for bone resorption and bone formation/turnover biomarkers. In subsets of the study population, adjunctive SDD significantly reduced serum biomarkers of bone resorption (biomarkers of bone formation were unaffected), consistent with reduced risk of future systemic bone loss in these post-menopausal women not yet on anti-osteoporotic drugs.

Updated quality assurance self-assessment exercise in intraoral and panoramic radiography

This updated self-assessment exercise for the dental team by the Radiology Practice Committee of the American Academy of Oral and Maxillofacial Radiology is intended to produce the highest quality diagnostic radiographs while keeping patient exposure as low as is reasonably achievable. To continue to provide the best radiographic services to patients, those involved in dental radiography need to be aware of the latest changes and advances in dental radiography and need to use them in their practice.

Significant reduction in dental cone beam computed tomography (CBCT) eye dose through the use of leaded glasses.

OBJECTIVE In light of the increased recognition of the potential for lens opacification after low-dose radiation exposures, we investigated the effect of leaded eyeglasses worn during dental cone-beam computerized tomography (CBCT) procedures on the radiation absorbed dose to the eye and suggest simple methods to reduce risk of radiation cataract development. STUDY DESIGN Dose measurements were conducted with the use of 3 anthropomorphic phantoms: male (Alderson radiation therapy phantom), female (CIRS), and juvenile male (CIRS). All exposures were performed on the same dental CBCT machine (Imtec, Ardmore, OK) using 2 different scanning techniques but with identical machine parameters (120 kVp, 3.8 mA, 7.8 s). Scans were performed with and without leaded glasses and repeated 3 times. All measurements were recorded using calibrated thermoluminescent dosimeters and optical luminescent dosimetry. RESULTS Leaded glasses worn by adult and pediatric patients during CBCT scans may reduce radiation dose to the lens of the eye by as much as 67% (from 0.135 ± 0.004 mGy to 0.044 ± 0.002 mGy in pediatric patients). CONCLUSIONS Leaded glasses do not appear to have a deleterious effect on the image quality in the area of clinical significance for dental imaging.

Causes of excessive bitewing exposureResults of a survey regarding radiographic equipment in New York

OBJECTIVE The purpose of this study was to identify the causes of excessive exposure in those dental practices that were found to use exceptionably high levels of radiation in bitewing radiography. STUDY DESIGN Using the parameters of the Dental Exposure Normalization Technique survey, certified radiation equipment safety officers conducted on-site inspections of 186 intraoral x-ray machines in 77 dental facilities. RESULTS In 23 facilities, the safety officers identified 43 units (23.1%) that delivered entrance exposures greater than 10% in excess of the upper limit of recommended exposures. For each of 27 (63%) of these units, the cause of the elevated exposure was clearly identifiable. CONCLUSIONS The factors contributing to increased exposure, listed from most frequent to least frequent, were as follows: improper processing, kilovoltage miscalibration, use of D-speed techniques with E-speed film, use of newly installed units with default timer settings that were too high, exposure timer failure, and insufficient half-value layer. Only 18% of the facilities surveyed reported using E-speed film.

Pilot study: digital subtraction radiography as a tool to assess alveolar bone changes in periodontitis patients under treatment with subantimicrobial doses of doxycycline.

BACKGROUND Subtle changes in marginal alveolar bone level can be demonstrated using digital subtraction of sequential radiographs. OBJECTIVE We aimed to evaluate the practical application of geometrically corrected digital subtraction in a clinical study of alveolar bone response to a drug previously shown to inhibit alveolar bone loss. STUDY DESIGN Selected periapical radiographs were acquired with projective standardization of patients with clinical marginal alveolar bone loss. Subsequently, patients received a 6-month regimen of subantimicrobial doxycycline or placebo. Standardized radiographs of the same alveolar regions were acquired after 3 and 6 months, and baseline radiographs were subtracted from these images. RESULTS Blinded digital subtraction analysis indicated various levels of marginal bone gain in 3 of the 6 patients in the experimental group, whereas in 3 of the 5 placebo patients the method showed bone loss. CONCLUSION These results suggest that geometrically corrected digital subtraction possibly agrees with clinical predictors of bone loss severity.

Juvenile dosimetry of panoramic and CBCT imaging for visualizing root resorption

Background: No studies have been done to evaluate radiation exposure to a 10 year old juvenile CIRS phantom using OSL dot dosimetry in conjunction with leaded glasses and thyroid shield, utilizing two and three dimensional imaging for orthodontic purposes. Methods: A juvenile anthropomorphic phantom corresponding to a 10 year old male was used for all exposures. Panoramic radiographs were taken on a Sirona Orthophos XG machine and CBCT scans were taken on a Carestream Kodak 9000 3D machine. The preset pediatric settings were used and with the CBCT, the field of view selected was to image the anterior maxilla, showing the canines and the surrounding area. The images were performed with and without leaded glasses and thyroid shield. Dosimetry was performed using Optically Stimulated Luminescent (OSL) dosimeters. The effective radiation dose was calculated for the organs of the head and neck. Organ fractions irradiated were determined from ICRP-89. Overall effective doses were calculated in micro-Sieverts for the results and were based on the ICRP-103 tissue weighting factors. Results: The effective doses measured with the Panoramic images were significantly less when compared to the CBCT scans. The highest organ dose exposures were in the salivary glands, oral mucosa, and extrathoracic airway. The use of leaded glasses and thyroid shield resulted in a dose reduction of 25% with both the Sirona Orthophos XG and the Kodak 9000 3D machines. Conclusion: This was the first study to evaluate radiation exposure to a 10 year old juvenile CIRS phantom using OSL dot dosimetry in conjunction with leaded glasses and thyroid shield, using two and three dimensional imaging for orthodontic purposes. Restricting field of view to the anterior maxillary region allows CBCT imaging to be used in specific clinical situations when three dimensional assessment of the presence and severity of root resorption is necessary.Purpose To evaluate laboratory and clinically the uncomplicated fragment reattachment using pinholes. Materials and Methods A total of 40 extracted human intact upper permanent central incisors with close similarity were selected and randomly divided into four groups (n = 10) according to the technique of reattachment. The incisal third of 30 specimens were sectioned horizontally. Group I: pinholes, group II: internal dentinal groove, group III: simple reattachment, and group IV (control group): intact teeth. Each fragment was reattached to its sectioned tooth using adhesive bond and resin cement. All specimens were tested for fracture strength under standard conditions in an Instron testing machine. The clinical study was performed on 20 patients, aged 8–16 years, presented with uncomplicated fragments of fractured upper central incisors, and divided into two groups (10 patients each). Group I: pinholes and group II: internal dentinal groove. All patients were followed-up clinically and radiographically at 3, 6, 12, and 18 months. Data were analyzed using one-way analysis of variance and post-hoc test with the significant level P less than 0.05. Results The laboratory study showed that the control group recorded the high strength value followed by pinholes, internal groove, and simple reattachment and the difference was statistically significant. However, the clinical results showed no significant differences between the two techniques. Conclusion It was concluded that the pinholes technique had only a significant effect on fragment reattachment success in the in-vitro study.