Important radiographic features in the identification of osseous dysplasia-related osteomyelitis.

OBJECTIVES: The aims of this study were to identify radiographic features that distinguish osseous dysplasia-related osteomyelitis (OD-related OM) from OD without OM and to detect possible causes of OD-related OM. STUDY DESIGN: Seventeen OD cases with and without OM were examined on planar and volumetric (cone beam computed tomography or multidetector computed tomography) imaging. Cases were divided into 3 groups based on clinical data: symptomatic OM, incidental (asymptomatic) OM, and control (OD without OM). Images were reviewed by 3 precalibrated observers, blinded to clinical information, for OD characteristics (location and extent); radiographic features of OD-related OM; and possible causes. Radiographic features of OD-related OM chosen by at least 2 observers were statistically analyzed within and between groups. RESULTS: Discontinuity of the cortical plates, widening of the radiolucent rim, decreased attenuation of the radiolucent rim, and sequestrum formation were significantly more common in symptomatic and incidental OM groups than in the control group (P ≤ .05). Two causes, atrophy of the edentulous ridge and presence of a periapical lesion, were also correlated with OD-related OM (P ≤ .05, P ≤ .01, respectively). CONCLUSIONS: Radiographic features can distinguish OD-related OM from OD. Familiarity with these radiographic features and possible causes may help improve the identification of secondarily infected OD.

Mandibular changes on panoramic imaging after head and neck radiotherapy.

OBJECTIVES: Changes to the radiographic appearance of the jaws after head and neck radiotherapy have not been thoroughly characterized. This retrospective study examines changes to the appearance of the mandible on panoramic images following intensity-modulated radiotherapy (IMRT) and relates these changes to medical co-morbidities and radiation dose. STUDY DESIGN: The medical and dental charts, and panoramic images of 126 patients who received IMRT at the Princess Margaret Hospital between January 1, 2005, and December 31, 2008, were analyzed independently by three observers. RESULTS: Of the 126 patients, 75 (60%) had post-IMRT changes, as seen on panoramic images; most, 66 (88%), consisted of widened periodontal ligament space (WPLS). The median time to WPLS was 29 months after IMRT. Female gender and radiation dose correlated with decreased time to WPLS. CONCLUSIONS: These results indicate that WPLS is a common radiographic sequela after head and neck radiotherapy, underscoring its clinical significance as a reliable marker of irradiated bone. Furthermore, this type of WPLS needs to be differentiated from odontogenic inflammatory disease and cancer recurrence to avoid unnecessary treatment that may precipitate osteoradionecrosis.

The effects of voxel size on cone beam computed tomography images of the temporomandibular joints.

OBJECTIVES: This clinical study assesses the effect of cone beam computed tomography (CBCT) voxel size on the ability to detect osseous changes associated with degenerative disease of the temporomandibular joint (TMJ). The effect of voxel size on perceived CBCT image quality is also evaluated. STUDY DESIGN: Twenty-two patients presenting for TMJ imaging with suspected degenerative disease were imaged with the Carestream 9000 CBCT unit, using separate right and left joint acquisitions (n = 44). Images were archived at native and downsampled voxel resolutions of 76 µm and 300 µm, respectively. Three oral and maxillofacial radiologists evaluated the images for osseous changes, as well as image quality by using a visual analog scale. RESULTS: There was no statistically significant difference between the voxel sizes in the detection of TMJ osteoarthritic changes. The mean visual analog scale response did, however, differ significantly between the two groups (P = .02). CONCLUSIONS: Despite no improvement in diagnostic efficacy with a smaller voxel size, perceived image quality is consistently higher for images with greater spatial resolution.

Performance of titanium alloy sintered porous-surfaced (SPS) implants supporting mandibular overdentures during a 20-year prospective study.

OBJECTIVE: This study was undertaken to assess short, sintered porous-surfaced (SPS), press-fit implants with mandibular overdentures to restore edentulous patients with severe mandibular resorption. MATERIALS AND METHODS: Implant lengths of 7, 8, 9, and 10 mm were used, all with 2-mm polished collars, making the designed intrabony lengths 5, 6, 7, and 8 mm. Each patient received three non-splinted implants placed using a two-stage protocol. RESULTS: Only 22 (with 53 implants) of the original 52 patients were available after 20 years. All but one of these patients was functioning with their implant-retained overdentures. Life table analysis accounted for all patients and implants, and showed a 20-year survival of 73.4%. Analysis of carefully standardized radiographs revealed mean cumulative bone loss after 20 years of 0.67 mm relative to the polished collar-SPS junction. CONCLUSIONS: Short SPS implants with mandibular overdentures can provide an acceptable treatment over a 20-year period for fully edentulous patients with severe alveolar resorption.

A retrospective analysis of referral patterns for oral radiologic consultation over 3 years in Ontario, Canada.

OBJECTIVES: To determine the types of practitioners who most commonly refer and the film type and diagnostic entities that are most frequently submitted for oral radiologic consultation in Ontario, Canada. STUDY DESIGN: A total of 430 referral letters and responses from 2 Ontario oral radiologists from 2003 to 2005 were analyzed. Data collected included the specialty of the referring practitioner, the film type(s) submitted, the radiographic density of the entity of interest, and the interpretation by the radiologist. RESULTS: General practitioners (58.9%) and oral surgeons (21.5%) were the most frequently referring practitioner types, representing 1.2% and 17.1% respectively of each group practicing in Ontario. Also, 18.2% of oral pathologists referred. Panoramic radiographs (79.5%) were included in referrals more often than intraoral radiographs (46.0%). Of the entities, 37.0% were radiopacities, 27.4% were radiolucencies, and 13.5% had mixed radiopaque-radiolucent density. The radiologists interpreted normal features (55.6%) most often. CONCLUSION: Panoramic radiographs with normal findings were submitted to oral radiologists for consultation most frequently in Ontario.

The role of basic sciences in diagnostic oral radiology.

Although it is generally taken for granted that dental education must include both basic science and feature-based knowledge components, little is known about their relative roles in visual interpretation of radiographs. The objectives of this study were twofold. First, we sought to compare the educational efficacy of three learning strategies in diagnostic radiology: one that used basic scientific (pathophysiologic) information, one that used feature lists structured with an organizational tool, and one that used unstructured feature lists. Our second objective was to determine whether basic scientific information provides conceptual coherence or is merely a simple means for organizing feature-based knowledge. Predoctoral dental and undergraduate dental hygiene students (n=96) were randomly assigned into three groups (basic science, structured algorithm, and feature list) and were taught four confusable intrabony entities. The students completed diagnostic and memory tests immediately after learning and one week later, and these data were subjected to a 3x2 repeated measures ANOVA. For the diagnostic test, students in the basic science group outperformed those assigned to the feature list and structured algorithm groups on immediate and delayed testing (p<0.05). A main effect of learning condition was found to be significant. On the memory test, performance was similar across all three groups, and no significant effects were found. The results of this study support the critical role of basic scientific knowledge in diagnostic radiology. This study also refutes the organized learning theory and provides support for the conceptual coherence theory as a possible explanation for the process by which basic science aids in diagnosis.

Use of sintered porous-surfaced dental implants to restore single teeth in the maxilla: a 7- to 9-year follow-up.

This report from a prospective study discusses the status of a group of 20 single maxillary sintered porous-surfaced (SPS) dental implants after 7 to 9 years in function restored with screw-retained crowns. Twenty patients each received a single SPS implant placed in a two-stage surgical approach; 65% replaced premolar or molar teeth, while the remainder replaced anterior teeth. Patients were examined annually. Standardized radiographs were used to assess peri-implant crestal bone levels and to determine an implant success rate. Jemt Papilla Index scores were used to assess the extent of papilla reformation between each implant and its two contiguous teeth. After 7 to 9 years, 17 implants were available for assessment (one patient had died, and two patients had moved away). One implant was removed after the 9-year visit because of progressive bone loss, giving a survival rate of 92.9%. The failure of this implant was related to deficiency in initial alveolar ridge width with loss of the remaining thin buccal cortical plate. With the exception of the failed implant, no significant changes in mean annual crestal bone loss were noted from years 1 to 9, giving a similar success rate (92.9%). Jemt Papilla Index scores of 2 or 3 were assigned for the majority of papillae. SPS implants can be used effectively to replace single missing maxillary teeth.

The evolution and application of dental maxillofacial imaging modalities.

During the last decades, an exciting new array of imaging modalities, such as digital imaging, CT, MRI, positron emission tomography, and cone-beam CT (CBCT), has provided astounding new images that continually contribute to the accuracy of diagnostic tasks of the maxillofacial region. The most recent, cone-beam imaging, is gaining rapid acceptance in dentistry because it provides cross-sectional imaging that is often a valuable supplement to intraoral and panoramic radiographs. The information content in such examinations is high and the dose and costs are low. The increasing trend toward the use of CBCT in dental offices may be expected to result in improved diagnosis, but with increased patient dose and health care costs. Using CBCT as a secondary imaging tool helps optimize health-to-risk ratio.

Ultrashort sintered porous-surfaced dental implants used to replace posterior teeth.

BACKGROUND: This retrospective multicenter report provides data from a case series of partially edentulous subjects treated with an ultrashort (5-mm-long) sintered porous-surfaced (SPS) dental implant. METHODS: The implant used had a tapered truncated cone shape, was 5-mm long, and had a maximal coronal diameter of 5 mm. Twenty-six implants were placed in 20 subjects to replace primarily maxillary and mandibular molar teeth. Submerged primary healing was used. Nine implants were restored with single crowns, one carried a single cantilever, and the remaining 16 implants were part of fixed implant-supported bridges, generally as the most distal abutment. RESULTS: After functional periods of 1 to 8 years, two maxillary implants failed, giving maxillary and mandibular failure rates of 14.3% and 0%, respectively. CONCLUSION: The results of this case series suggest that an SPS, press-fit, tapered dental implant with a length of 5 mm and a maximal coronal diameter of 5 mm should be investigated further as a solution for the management of highly resorbed posterior sites in partial edentulism, particularly in the mandible.

An assessment of crown-to-root ratios with short sintered porous-surfaced implants supporting prostheses in partially edentulous patients.

PURPOSE: Implant length, implant surface area, and crown-to-root (c/r) ratio and their relationship to crestal bone levels were analyzed in 2 groups of partially edentulous patients treated with sintered porous-surfaced dental implants. MATERIALS AND METHODS: One hundred ninety-nine implants were used to restore 74 partially edentulous patients with fixed prostheses. Implants were categorized according to their length ("short" versus "long") and estimated surface area ("small" versus "large"). "Short" implants had lengths of 5 or 7 mm, while "long" implants were either 9 or 12 mm in length. "Small" implants had estimated surface areas of < or = 600 mm2, while "large" implants had estimated surface areas > 600 mm2. Other data collected included c/r ratio (measured on articulated diagnostic casts), whether or not the implants were splinted, and standardized sequential radiographs. RESULTS: The mean c/r ratio was 1.5 (SD = 0.4; range 0.8 to 3.0), with 78.9% of the implants having a c/r ratio between 1.1 and 2.0. Neither c/r ratio nor estimated implant surface area (small or large) affected steady-state crestal bone levels. However, implant length and whether the implants were splinted did appear to affect bone levels. Long implants had greater crestal bone loss (0.2 mm more) than short implants; splinted implants showed greater crestal bone loss (0.2 mm more) than nonsplinted ones. These differences were statistically significant. DISCUSSION AND CONCLUSIONS: Sintered porous-surfaced implants performed well in short lengths (7 mm or less) in this series of partially edentulous patients. The data suggested that long implants and/or splinting can result in greater crestal bone loss; longer implants and splinted implants appeared to favor greater crestal bone loss in this investigation. These conclusions are, of course, specific to the implants used and would not be relevant to other implant types.

Ten-year results of a prospective study using porous-surfaced dental implants and a mandibular overdenture.

BACKGROUND: Numerous investigators have used osseointegrated dental implants as retention for mandibular overdentures, but few have reported 10-year outcomes or incorporated carefully standardized radiographs to document crestal bone loss. PURPOSE: The purpose of this study was to use a prospective clinical trial design to assess the performance of short sintered porous-surfaced dental implants with a mandibular complete overdenture when all patients in the trial had undergone 10 years of continuous function. MATERIALS AND METHODS: Fifty-two fully edentulous patients, most with advanced alveolar ridge resorption, each received three free-standing Endopore implants (7-10 mm in length, mean length, 8.7 mm; Innova Corporation, Toronto, ON, Canada) in the mandibular symphysis region. After 10 weeks of submerged healing, these implants were used to support an overdenture. Carefully standardized radiographs, using a customized stainless steel filmholder attached to each implant and the x-ray tube, were collected at baseline, 3 months, 6 months, yearly to 5 years, and then again at 7and 10 years. RESULTS: Life table analysis revealed a 10-year implant survival of 92.7% and a mean annual bone loss after year 1 of 0.03 mm. CONCLUSION: Short free-standing dental implants with a sintered porous surface used for implant fixation are a predictable and effective means of retaining a mandibular overdenture in patients with advanced mandibular ridge resorption.

Managing the posterior mandible of partially edentulous patients with short, porous-surfaced dental implants: early data from a clinical trial / Gerenciamento da mandíbula posterior de pacientes parcialmente desdentados com superfície porosa: primeiros dados de um processo clínico

Forty-eight endopore dental implants were placed in the posterior mandibles of 24 partially edentulous patients. Seventeen of these implants replaced premolar teeth, while 31 replaced molars. Only 7-mm and 9-mm implants were used, and the majority of prosthetic restorations (83 percent) were single crowns. After a mean functional time of 32.6 months (range, 8.2 to 50.3 months), the implant survival rate was 100 percent and assessment of available radiographic data showed minimal to no crestal bone loss