Central giant cell granuloma of the mandibular condyle: a case report and review of the literature.

Central giant cell granuloma (CGCG) is a benign intraosseous lesion. The true nature of this lesion is controversial and remains unknown; the three competing theories are that it could be a reactive lesion, a developmental anomaly or a benign neoplasm. Furthermore, the actual aetiology of CGCG is still unclear, although inflammation, haemorrhage and local trauma have all been suggested; it has also been hypothesized that CGCG may have a genetic aetiology. Lesions central to the mandibular condylar head are very rare, with only three documented cases in the English language literature, none of which elaborates on the CT features. In this case report, a 31-year-old male patient complaining of a left pre-auricular mass underwent radiographic investigation. CT images revealed a lesion central to the mandibular condyle and demonstrated features that were highly suggestive of CGCG. The patient underwent surgical curettage, and the subsequent histopathological examination confirmed the diagnosis of CGCG. 3 years after the procedure the patient presented with a recurrence and underwent complete resection of the mandibular condyle with immediate reconstruction. This report presents CT characteristics of a rare occurrence of CGCG of the mandibular condyle, compares it with other published cases and poses the question of the role of radiology in predicting the degree of aggressive behaviour of these lesions before surgery.

Gorham's disease of the maxilla: a case report.

A case of Gorham's disease in the maxilla of a 56-year-old male patient is described. The clinical presentation, radiographic and histopathological features and treatment are presented. A discussion of the current understanding of this rare disease, based on review of the literature, is offered.

The occurrence of keratocystic odontogenic tumours in nevoid basal cell carcinoma syndrome.

OBJECTIVES: This retrospective study reviews the occurrence of keratocystic odontogenic tumours (KOTs) in nevoid basal cell carcinoma syndrome (NBCCS) patients seen in the Oral and Maxillofacial Radiology Special Procedures Clinic in the Faculty of Dentistry at the University of Toronto. METHODS: This study examines the number and radiographic features of KOTs identified in 11 NBCCS patients who presented with 43 KOTs between January 1989 and 30 June 2007 on plain film radiographs and CT. RESULTS: Regression analysis revealed a statistically significant (P < 0.01) relationship between the age at first KOT occurrence and the total number of lifetime KOTs (r = -0.78). Of the KOTs identified, 25 developed in the mandible and 18 developed in the maxillae. The majority of these were associated with a change in either the size or shape of the follicular space, and both plain film radiography and CT were equally effective at demonstrating these changes. CT was, however, more effective at demonstrating endosteal scalloping of cortical bone than plain film radiography (P < 0.001) while the opposite was true for showing tooth displacement (P < 0.01). For patients imaged with both plain radiography and CT (29 KOTs), 5 KOTs were detectable only by CT. CONCLUSIONS: Our results suggest that there should be early and frequent monitoring of NBCCS patients for the development of KOTs in youth and adolescence, and that CT imaging should play an important role in these investigations.

Methods of determining the relationship of the mandibular canal and third molars: a survey of Australian oral and maxillofacial surgeons.

BACKGROUND: Surgical extraction of third molars is one of the most common oral and maxillofacial surgical procedures performed and may have a number of associated complications. One of these complications is inferior alveolar nerve (IAN) dysaesthesia or impairment of sensory perception (including paraesthesia and/or anaesthesia). Previous studies assume that most clinicians use various combinations of nine radiologic criteria on panoramic radiographs as indicators of the relationship and, therefore, predictors of the risk of postoperative dysaesthesia. Our study assessed both the current radiologic modalities and assessment criteria used by Australian oral and maxillofacial surgeons when determining the proximity of mandibular canal to third molars. METHODS: A survey of all surgeon members of the Australian and New Zealand Association of Oral and Maxillofacial Surgeons (ANZOMS) practising in Australia was undertaken. RESULTS: Of the 105 questionnaires sent to surgeons, 72 responses (68 per cent) were returned. All surgeons reported using the panoramic radiograph but only 25 per cent considered it sufficiently accurate in determining the relationship between the mandibular canal (MC) and the third molar root, while 61 per cent of surgeons use CT for this purpose but the average frequency of use was very low (five per cent). This study also revealed that the nine radiologic criteria on a panoramic radiograph are used to varying extents by Australian surgeons. Nearly all surgeons use 'change in MC direction' and 'MC narrowing' to determine and close relationship. Thirty-one per cent used superimposition of the MC and the root of the third molar alone and 24 per cent used appearance of contact of the root with the MC alone in the absence of any other radiologic criteria to indicate close or intimate relationship. CONCLUSION: Further research is required to determine the accuracy and observer agreement or reliability of using the nine panoramic characteristics, to determine this relationship and whether the presurgical determination of proximity and position (buccal or lingual) of the canal utilizing CT has any usefulness in determining the surgical protocol or affect on postoperative morbidity.

Periapical health and treatment quality assessment of root-filled teeth in two Canadian populations.

AIM: The prevalence of apical periodontitis (AP) and the quality of root fillings and restorations were determined in two Canadian populations differing in avail-ability of endodontists. METHODOLOGY: Radiographs of first-time university patients aged 25-40 years in Toronto and Saskatoon were examined for missing teeth, presence and standard of root fillings, standard of restoration, and AP according to the Periapical Index. Patients with root-filled teeth were invited for clinical examination and interview to inspect the restorations, and to reveal the providers of endodontic treatment and reasons for extractions of missing teeth. Chi-square and independent t-tests interpreted at the 5% significance level were used to examine associations between the prevalence of AP in root-filled teeth and the standard of the root filling, restoration, and providers of treatment. RESULTS: Proportion of patients with root-filled teeth was significantly higher (P < 0.001) in Toronto than in Saskatoon (39 and 26%, respectively). Presence of AP about root-filled teeth (44% in Toronto, 51% in Saskatoon) was significantly associated with poor density (OR = 2.7) short (OR = 2.4) and long (OR = 2.8) root fillings, and with poor radiographic quality of the restoration (OR = 1.7) Prevalence of AP did not differ significantly between teeth treated by generalists and endodontists. CONCLUSIONS: The prevalence of AP in root-filled and untreated teeth was comparable to that reported in previous methodologically compatible studies. The quality of both the root filling and the restoration were found to impact on the periapical health of root-filled teeth, with the impact of the restoration being most critical when the quality of the root filling was adequate.

Imaging techniques and image interpretation for dental implant treatment.

PURPOSE: This article reviews the literature on radiographic imaging techniques and image interpretation for dental implant treatment. MATERIALS AND METHODS: MEDLINE was used to identify published peer-reviewed literature for this report. RESULTS: Radiographic images are indispensable in the evaluation of osseous structures when planning treatment for dental implants. Potential bone sites for implant placement can be assessed clinically by means of palpation or probing through the mucosa; however, diagnostic imaging provides the best means for indirectly measuring bone dimensions. After healing of the implant site, the application of radiology is useful to verify the amount of bone adjacent to the implant and that the transmucosal abutments fit the implant. Upon completion of the implant prosthesis, radiology may be used to monitor initial and long-term success of implant treatment. CONCLUSION: Recommendations for the application of radiology over the course of treatment are made for various implant cases ranging from the overdenture to the single-tooth implant.

Influence of the addition of restorations on the diagnosis of caries from digitized bitewing radiographs.

OBJECTIVES: The purpose of this study was to assess the influence of additional caries and restorations on the detection of caries on the same radiograph. STUDY DESIGN: Six participants examined five series of four radiographs in which natural carious lesions were present. Each series consisted of the same image with progressively more restorative treatment digitally painted on. The films were randomly presented to the observers who examined the films for the presence and depth of carious lesions. The observers were not informed that the 20 films were disguised versions of the same original five radiographs. RESULTS: The number of carious lesions reported by the six observers did not increase despite the apparent increased restorative intervention viewed on the radiographs. CONCLUSIONS: The complexity of restorative care does not affect observers' ability to correctly detect approximal carious lesions.

Characteristics of an oral and maxillofacial radiology department. Report of the ad hoc Department Characteristics Committee of the American Academy of Oral and Maxillofacial Radiology.

Oral and maxillofacial radiology is a dynamic and multifaceted discipline that plays a critical role in patient care, the education of general dentists and dental specialists, and the academic health of the dental school. Diagnostic and treatment advances in temporomandibular joint disorders (TMD), implants trauma and orthognathic surgery, and craniofacial abnormalities depend heavily on conventional and advanced imaging techniques. Oral and maxillofacial radiology contributes to the education of pre- and post-doctoral dental students with respect to biomedical and clinical knowledge, cognitive and psychomotor skills, and the professional and ethical values necessary to properly prescribe, obtain, and interpret radiographs. The development of an active and successful oral and maxillofacial radiology department, division, or section requires the committment of institutional resources. This document may serve as a guide to dental schools committed to excellence in oral and maxillofacial radiology.

Restorative certainty and varying perceptions of dental caries depth among dentists.

OBJECTIVE: The question of whether dentists who most frequently identify tooth surfaces for definite restoration perceive dental caries as significantly deeper than other dentists is assessed. METHODS: One group of 20 dentists independently examined 145 unrestored approximal tooth surfaces on 16 bitewing radiographs and recorded their restorative and depth decisions. Another group of 15 dentists similarly scored 304 unrestored surfaces on 30 bitewing radiographs. Each group of dentists was later divided into four subgroups according to the number of surfaces designated for definite restoration by each dentist. RESULTS: As the number of tooth surfaces designated for definite restoration increased, mean caries depth (P < .05 for the high vs low subgroups) and the percent of dentinally carious surfaces increased, while the percent of surfaces assessed as sound decreased. Dentists with the lower numbers of surfaces designated for definite restoration came closest to the true histologic mean caries depth of the examined tooth surfaces. CONCLUSIONS: Dentists who designated high numbers of approximal tooth surfaces for definite restoration assessed caries as deeper than other dentists, and deeper than was proven histologically.

Radiographic features of segmental odontomaxillary dysplasia: a study of 12 cases.

The purpose of the study was to analyze the radiographic features of segmental odontomaxillary dysplasia by studying the radiographs of 12 new cases. With a standard data collection form, the radiographic characteristics were assessed by the two principal investigators who studied available radiographs of all cases. As in previously reported cases, abnormal findings in all patients were confined to the posterior segment of one maxilla. The most common findings in the cases studied were sclerosis and thickening of bony trabeculae, missing permanent premolar teeth, abnormal spacing of primary molars vertical orientation of bony trabeculae, a smaller maxillary sinus, and delayed eruption of permanent posterior teeth. Less commonly observed features were enlarged crowns, roots, and pulps of primary molars, irregular resorption of primary molar roots, mediolateral expansion of the alveolar process, splayed roots of primary molars, and an abnormal medial position of the teeth.

A radiological analysis of chronic sclerosing osteomyelitis of the mandible.

OBJECTIVE: To determine the frequency of specific characteristics of chronic sclerosing osteomyelitis (CSO) of the mandible in plain films compared with CT scans. METHODS: After calibration, three observers studied 13 cases of plain films and 11 sets of separated and masked CT scans from the same cases. Controls consisted of cases of fibro-osseous disease with a similar appearance. Comparison with the results of nuclear scans of eight of the cases was made. RESULTS: Periosteal new bone formation, sclerosis and bone enlargement were the most common characteristics. When the CT scans were analysed, detection of sequestra improved from 45 to 91%. There was greater agreement between observers when analysing CT scans compared with plain films. The results of the gallium scans supported the diagnosis in only two of the eight cases. CONCLUSION: In this study, the CT scans were the most reliable imaging method for revealing characteristics such as sequestra which are useful for the diagnosis of CSO.

Radiographic features of the mandible in neurofibromatosis: a report of 10 cases and review of the literature.

The radiographs of 10 cases with a diagnosis of neurofibromatosis involving the mandible were evaluated by two reviewers to document common radiographic characteristics. The most common findings included increase in bone density, enlarged mandibular foramen, lateral bowing of the mandibular ramus, increase in dimensions of the coronoid notch, and a decrease in the mandibular angle. The six cases for which computed tomography scans were available, enlargement of the mandibular foramen and concavity of the medial surface of the ramus were seen. In five of these cases, there was no associated tumor mass adjacent to the concavity; instead a soft tissue mass with density of fat was found. This supports the theory that neurofibromatosis may have manifestations of a mesodermal dysplasia.

Radiographic differentiation of osteogenic sarcoma, osteomyelitis, and fibrous dysplasia of the jaws.

UNLABELLED: Biopsy and histopathologic analysis may fail to consistently separate osteogenic sarcoma, osteomyelitis, and fibrous dysplasia. OBJECTIVES: To establish useful radiographic characteristics to differentiate these diseases, an objective preliminary study of radiographs of 30 cases of these diseases was done. STUDY DESIGN: After precisely defining several radiographic characteristics and completing a calibration study, three observers unaware of the diagnosis examined study cases that were randomly ordered. RESULTS: Despite using trained observers and strict criteria, differentiation of the three conditions is difficult on the basis of radiographic features alone. In osteogenic sarcoma, the distinguishing features were: permeative lesion borders, stippled bone pattern, destruction of cortical outlines, perpendicular spiculations of periosteal new bone, destruction of lamina dura, and widening of the entire periodontal ligament space. Presence of sequestra and laminations of periosteal new bone were the most useful distinguishing features in cases of osteomyelitis that otherwise resemble fibrous dysplasia. In fibrous dysplasia, superior displacement of the mandibular canal and a fingerprint bone pattern were pathognomonic. Displacement of the maxillary sinus cortex, alteration of lamina dura to the abnormal bone pattern, and narrowing of the periodontal ligament space were also useful distinguishing features. CONCLUSIONS: Our findings indicate that diagnosis cannot rely on radiographic characteristics alone, although some radiographic findings were more useful than others.

A radiographic comparison of apical root resorption after orthodontic treatment with the edgewise and Speed appliances.

Apical root resorption is a serious iatrogenic problem sometimes associated with orthodontic treatment. The Speed appliance (Strite Industries, Ltd., Ontario, Canada) provides a continuous rotatory and torque action through its spring clip mechanism, in contrast with the edgewise appliance that may provide an interrupted force. The effect of continuous action on root resorption compared with the interrupted action of the edgewise system has not been investigated previously. The purpose of the present investigation is to test the null hypothesis that there is no difference in the apical root resorption seen after orthodontic treatment with the edgewise straight wire and the Speed appliance systems. Pretreatment and posttreatment periapical radiographs of 63 patients, (30 treated with the Speed 0.018 bracket and 33 with the 0.018 edgewise bracket) were studied. The long cone paralleling technique was used for all the radiographs. Any image distortion between the pretreatment and posttreatment radiograph was calculated and compensated for by using the crown length measurements, on the assumption that the crown length remains unaltered during the treatment period. Quantitative measurements of crown and root lengths for the maxillary and the mandibular central and lateral incisors were compared. Means and standard deviations for the percentage root resorption per tooth group were calculated. A three-factor analysis for variance (ANOVA test) was performed to determine whether there was an appliance, treatment, or gender effect on the amount of root resorption seen after treatment. No statistically significant difference in root resorption between the two appliance systems was found.(ABSTRACT TRUNCATED AT 250 WORDS)

Odontogenic infections: Part one. Anatomy and radiology.

Odontogenic infections are frequently encountered by the dentist. The signs and symptoms of these common dental emergencies are outlined in this two-part article. A thorough knowledge of the fascial planes and anatomical routes of infection spread is a critical prerequisite to understanding the clinical manifestations, potential complications, and appropriate management of these infections.

Temporomandibular joint imaging.

New advances in imaging have added a significant amount of information, which has resulted in more accurate and detailed diagnosis of temporomandibular joint disorders. In the future, treatment methods may be devised that can use effectively this diagnostic information.

Evaluation of temporomandibular joint internal derangement.

The incidence of internal derangement of the temporomandibular joint has been documented in patients with temporomandibular disorders. However, the detection and diagnosis of a displacement of the temporomandibular joint disc in relation to internal derangement is not always accurate, and it varies according to the method of examination. A prospective clinical investigation of 26 patients (45 temporomandibular joints) with signs and symptoms of temporomandibular joint pain and dysfunction was completed to examine the accuracy of clinical examination, sagittal recording device tracings, arthrography, and magnetic resonance imaging in detecting internal derangement in the temporomandibular joint. A group of 16 asymptomatic control subjects (32 temporomandibular joints) was examined for the presence of internal derangement by the methods under consideration. Incidence of bilateral internal derangement in the temporomandibular joints of the symptomatic patients was also assessed. Findings obtained through clinical examination and sagittal recording device tracings agreed most often with the arthrographic findings of internal derangement. Magnetic resonance imaging often failed to detect the presence of arthrographically detected internal derangement. Internal derangement was identified bilaterally in a significant number of patients, despite the absence of bilateral symptoms. This incidence varied according to the technique used. In the control group, 9% of the temporomandibular joints that had been assessed as normal according to clinical examination and sagittal recording device tracings were found to have internal derangement according to magnetic resonance imaging.

Imaging techniques and their clinical significance.

A variety of imaging modalities are available for the preoperative evaluation of potential implant sites. The pantomograph provides initial screening information. Cephalometric films are most useful in analyzing the incisor regions. Tomography can provide cross-sectional views of segments at a relatively low patient radiation dose. Computed tomography is a superior method when the analysis of complete arches is required. Experimental designs of postoperative radiologic evaluation of small changes in bone height require reproducible image geometry and the evaluation of intraobserver error.