Salivary duct strictures: nature and incidence in benign salivary obstruction

OBJECTIVES

The aim of this study was to establish the incidence and character of salivary duct strictures by carrying out a 10 year retrospective review. Salivary gland obstruction is most commonly caused either by salivary calculi or duct strictures. These strictures or stenoses develop secondarily to inflammation in the duct wall and may be single or multiple.

METHODS

All reports of sialographic examinations performed on patients referred to the Dental Radiology Department in a London Dental Hospital between 1995 and 2004 were reviewed and those patients with symptoms of salivary obstruction identified. In total, 1362 sialograms using the conventional hand injection technique with water-soluble contrast media were performed on 1349 patients with obstructive symptoms during the 10-year period.

RESULTS

Of the 1362 sialograms performed, the reports revealed that 877 (64.4%) showed evidence of benign intraductal obstruction. The remaining 485 (35.6%) were normal. 642 of the cases (73.2%) revealing obstruction were reported to be due to salivary calculi, 198 due to duct strictures (22.6%) and the remaining 37 (4.2%) were considered to be due to mucous plugs. Detailed analysis of the patients with strictures showed they were more common in women with a mean age of 52 years. Single strictures were evident in 66.7% of cases while 33.3% showed multiple stenoses. Strictures were more common in the parotid duct (75.3%). 7% of patients presented with bilateral stenoses.

CONCLUSION

This is the largest review of duct strictures to be reported. It has shown that ductal stricture formation accounts for almost 25% of cases of benign salivary obstruction and appears to have been an under-recognized condition. Strictures more commonly affect parotid ducts and are typically found in the fourth, fifth or sixth decades, particularly in women.

Comparison of ultrasound, digital and conventional radiography in differentiating periapical lesions

OBJECTIVES

To carry out an in vivo comparative pilot study to evaluate the efficacy of ultrasound, digital (DR) and conventional plain film-based imaging (PF) in the differential diagnosis of periapical lesions.

METHODS

Fifteen patients aged between 13 years and 40 years with periapical lesions associated with anterior maxillary or mandibular teeth requiring endodontic surgery were selected and consented for the study. Pre-operative periapical radiographs (PF) and charge coupled device (CCD) DR were obtained. Measurements and provisional diagnoses of the apical areas were made by three specialist observers (two dental radiologists and one endodontist) on three separate occasions. Pre-operative ultrasound examinations were then performed and the images assessed by two specialist observers (ultrasonographer and endodontist) for the size, contents, vascular supply and a provisional diagnosis made as to whether the lesion was a cyst or granuloma. Endodontic surgery was performed including curettage of the apical tissues to enable histopathological investigation, which provided the gold standard diagnosis. All measurements and findings were compared and statistically analysed.

RESULTS

On PF and DR the periapical lesions were readily identified but observers were unable to differentiate granuloma from cyst using either modality. Dimensional measurements were subject to greater interobserver variation on DR than on PF. Where sufficient buccal cortical bone had been resorbed, ultrasound imaging was straightforward but underestimated the size of the lesions compared with PF and DR. In all 15 cases, the ultrasound diagnosis agreed with the histopathological gold standard.

CONCLUSIONS

PF and DR enable diagnosis of periapical disease existence, but not of its nature; while ultrasound underestimates the extent of disease, but can provide accurate information on the pathological nature of the lesion.

What happens if you delay scanning Digora phosphor storage plates (PSPs) for up to 4 hours?

OBJECTIVES

To assess, both objectively and subjectively, the effects of different combinations of storage conditions and delaying scanning for up to 4 h on digital images captured using Digora phosphor storage plates (PSPs).

METHOD

Standardized images were obtained of an aluminium step wedge and dry mandible in acrylic using GE 1000 and phosphor storage plates (PSPs) from the Digora (Soredex) digital system. 12 plates were exposed and immediately scanned to produce the baseline gold standard. The plates were re-exposed and stored using three different storage combinations--(A) ambient temperature, (R) refrigeration and (S) low humidity, and then scanned after 10 min, 30 min, 1 h, 2 h, 3 h or 4 h. The objective analysis was carried out by pixel density measurements and the data analysed statistically using analysis of variance. Subjective analysis was carried out by three oral radiologists and the results analysed using the Mann Whitney U-test.

RESULTS

Objective analysis showed loss of pixel density after 4 h using all storage combinations. Subjectively, this loss of density was not evident.

CONCLUSION

There is a loss of image density at 4 h when using Digora PSPs which can not be detected clinically, but could compromise multisite research.

Poland-Moebius syndrome: a case with oral anomalies

The combination of Moebius and Poland anomalies is rarely described in the literature. While some authors believe this association is an independent syndrome, others think that Poland, Moebius and Poland-Moebius syndromes are variations of the same condition. We report a case of Poland-Moebius syndrome in a 6-year-old girl who presented with bilateral convergent strabismus, the inability to abduct her eyes beyond the midline and brachydactyly of her right hand. Oral manifestations included incompetent lips and an abnormal tongue. Other facial features included hypoplasia of her mandible and her left ear at a slightly lower level than her right ear. Panoramic and lateral skull radiographs confirmed the absence of certain teeth and the hypoplastic mandible. The diagnosis of Poland-Moebius syndrome was made on the basis of cranial nerve involvement and oro-facial manifestations.

Osteopetrosis - a review and report of two cases

We present a brief review of the rare condition of osteopetrosis together with two case reports of this disease in the same family affecting the jaws. The first in a 41-year-old woman, and the second in her 39-year-old brother. Plain films and computed tomography showed marked sclerosis of the affected bones with obliteration of the medullary cavities and thickening of the cortices as well as multiple absent and unerupted teeth. In addition radiographs showed discrete mixed radiopaque/radiolucent areas consistent with the appearance of fibro-cemento-osseous dysplasia, but which may also represent part of the overall spectrum of bone changes in osteopetrosis.

Interpretation of skull radiographs for facial fractures by medical staff working in UK emergency departments: a pilot study

OBJECTIVES

This was a pilot study to determine the ability of hospital doctors (1) to assess the technical quality of occipitomental (OM) radiographs and (2) to identify facial fractures.

METHOD

Twenty-two doctors from four UK Accident and Emergency (A&E) departments participated in a two part study: Part A was a postal questionnaire containing questions on demographic data, educational background, selection criteria, assessing radiographs and radiation protection; and Part B was a clinical viewing session to interpret 20 randomized OM radiographs divided into four groups; technically good and poor without fractures, and technically good and poor with fractures.

RESULTS

Study participants ranged from junior house officers to senior consultants. There was considerable variation in educational background and radiographic interpretation instruction at undergraduate and postgraduate level. OM radiographs constituted 10% of all skull radiographs examined per week, yet only 40% of the doctors felt confident when assessing technical quality. The majority of participants had only a limited knowledge of radiation protection legislation. During the viewing session, only 50% of the participants correctly identified those radiographs with fractures and those with technique errors. There was no significant difference between house officers and other grades of staff. A higher level of seniority did not equate with greater interpretative ability. Subjective confidence in assessing film quality did not correlate with the actual film viewing.

CONCLUSION

Only half of the A&E doctors taking part in the study were able to correctly assess film quality and identify facial fractures on OM radiographs. If the pilot sample is representative, then the findings are of considerable concern.

Analysis of digital images acquired using different phosphor storage plates (PSPs) subjected to varying reading times and storage conditions

OBJECTIVES

To assess, both objectively and subjectively, the effects of different combinations of storage conditions and varying delays in reading on digital images captured using phosphor storage plates (PSPs).

METHOD

Standardized images were obtained of an aluminium step wedge and a dry mandible in acrylic using GE 1000 and PSPs from the Digora (Soredex) and DenOptix (Gendex) digital systems. Twelve plates from each system were exposed and immediately scanned to produce the baseline gold standard. The plates were re-exposed and stored using three different storage combinations, (A) ambient temperature, (R) refrigeration and (S) low humidity, and then scanned after 6 h, 12 h, 18 h, 24 h, 48 h or 72 h. Objective analysis was carried out by pixel density measurements and the data were analysed statistically using analysis of variance. Subjective analysis was carried by three oral radiologists and the results were analysed using Mann-Whitney U-test.

RESULTS

For the DenOptix system there were no differences either objectively or subjectively in the images obtained from all the plates using different storage conditions and after varying time intervals. For Digora, objective analysis showed loss of pixel density after 6 h using all storage conditions. This loss of density was also evident subjectively after 6 h on plates stored under certain storage conditions.

CONCLUSION

Storage of DenOptix PSPs for up to 72 h in different conditions does not affect the quality of the digital images. However, there is a loss of image density within 6 h when using Digora PSPs, which may affect clinical image interpretation.

Haemangioma of the body of the mandible: a case report

We present a case of haemangioma of the mandible in a 46-year-old woman. The radiological appearance was of a unilocular radiolucency that looked similar to other more common lesions of the mandible. This case shows that a potentially life-threatening haemangioma can present as an apparently benign cyst-like unilocular radiolucency, and highlights the need to include haemangioma in many differential diagnoses, and the importance of taking all radiological features into account.

Survey of radiography and radiation protection in general dental practice in Uganda

OBJECTIVES

To carry out the first survey in Uganda of all dentists and all public health dental officers (PHDO) to assess the status of dental radiography and radiation protection.

METHODS

All 74 dentists and 76 PHDOs in Uganda were sent a postal questionnaire including 33 questions relating to various demographic details, radiographic equipment and radiographic techniques, including processing and radiation protection. A second questionnaire was sent to non-respondents after 3 months.

RESULTS

Eighty-two per cent of dentists responded and 83% of PHDOs. Seventy per cent of the dentists and 100% of the PHDOs were trained in Uganda. Seventy-five per cent of the dentists and 30% of the PHDOs had access to one of the approximately 30 X-ray machines in the country. The majority of the equipment did not comply with current recommendations in Europe. Fifty-one per cent of dentists used machines with mechanical timers, 28% used machines with no visual warning signal and 17% used equipment with no audible warning signal. Most of the equipment was over 30 years old and only 15% of dentists knew when the equipment was last serviced. The most relevant finding of the surveys was the level of 'don't know' responses to many questions from both groups.

CONCLUSIONS

The lack of knowledge regarding dental radiography and radiation protection plus the condition of most equipment in Uganda is a matter of concern. Standards of care are considerably lower than in developed countries requiring improved undergraduate training, provision of postgraduate courses and Ugandan governmental or international financial assistance.

Survey of dental radiographic services in private dental clinics in Damascus, Syria

OBJECTIVES

To perform a radiographic survey of private dental clinics in Damascus, Syria using a postal questionnaire to produce recommendations for improving the quality of dental radiographic services and education in Syria.

METHODS

Three hundred private dental clinics in Damascus were surveyed using a postal questionnaire (in English and Arabic) containing 27 questions on demographic information, equipment, techniques, selection criteria, frequency of examinations, and undergraduate/ postgraduate education.

RESULTS

Two hundred and two (67%) dentists responded of which 95% graduated in Syria. The results showed a general lack of knowledge and understanding of dental radiography. Sixty four per cent did not know the kVp setting of their equipment, 73% used D-speed film, 57% did not use film holders and beam aiming devices, 25% did not use a viewing box. In addition, 45% of known equipment operated at 50 kVp or less and 16% was over 20 years old. No meaningful selection criteria existed with a wide variation in type and frequency of radiographs used for different clinical conditions. Syrian undergraduate training in dental radiology was minimal and there was no postgraduate education in the speciality.

CONCLUSIONS

Several areas of the radiographic service in Damascus fall short of current recommendations on good practice. Recommendations are made to improve the service, the quality of undergraduate education and to establish postgraduate education.

Radiographic diagnosis of root resorption in relation to orthodontics

The literature regarding external root resorption in relation to orthodontics and its radiographic diagnosis is reviewed, including a summary of the more common radiographic techniques available. Sample cases are presented which demonstrate the need for good radiographic technique and an awareness of the limitations of certain radiographs. A provisional diagnosis of external root resorption may need to be confirmed by further radiographic views where appropriate.

Intra-oral ultrasound imaging of a submandibular duct calculus

A case is presented showing the first reported use of a small, digitally-guided, intra-oral ultrasound probe to image a calculus in a submandibular salivary duct. This use of intra-oral ultrasound is discussed in the context of the overall current status of intra-oral and extra-oral ultrasound imaging. It is proposed that using a combination of intra-oral and extra-oral probes, the whole of the salivary apparatus may now be examined sonographically for the presence of calculi.

An evaluation of the diagnostic yield from bitewing radiographs of small approximal and occlusal carious lesions in a low prevalence sample in vitro using different film types and speeds

AIM

To compare diagnostic yield in caries diagnosis from D- and E-speed films.

DESIGN

A laboratory study.

SETTING

A UK dental school between 1992 and 1994.

MATERIALS AND METHODS

96 extracted teeth containing approximal and occlusal lesions, but representing a low caries prevalence sample, were set in occluding dental arches. Bitewing radiographs were taken and interpreted by 5 examiners for the presence or absence of caries. Each examiner was also asked which film image he or she subjectively liked best.

MAIN OUTCOME MEASURES

The teeth were subsequently sectioned and histologically examined to validate diagnostic decisions.

RESULTS

For all film types the percentage of lesions with caries histologically in dentine correctly identified radiologically (sensitivity) was low (approximal caries 8-22%; occlusal caries 0-30%). The number of sound dentine sites correctly identified (specificity) was high (approximal caries 98-100%; occlusal caries 79-100%). There were no significant differences between D- and E-speed films. Sensitivity was unaffected by each examiner's subjective preference for a particular film. The variation in sensitivity of diagnosis was due to differences between examiners.

CONCLUSIONS

The reluctance of many GDPs to use E-speed film because they 'do not like the image' cannot be endorsed or supported. Both E-speed film types examined can be recommended for use in general practice.

Stafne's bone cavity: a review of the literature and report of two cases

This paper reports two cases of Stafne's bone cavity, one of which shows apparent regression over a period of 8 years: an unusual feature that has not previously been reported. A comprehensive review of the literature dealing with this well demarcated mandibular radiolucency of unknown aetiology accompanies these two case reports.