Idiopathic Radiographic Apical Root Resorption in Wind Instrument Players

Root resorption of the permanent teeth involves an elaborate interaction among inflammatory cells resulting in loss of dental hard tissues. This report describes three clinical cases where idiopathic root resorption occurred in wind instrument playing patients. These patients produce adequate non-orthodontic forces, while playing their instruments, to expose their teeth to root resorbing force. Careful clinical monitoring of patients' teeth should be undertaken, as the additive effects of orthodontic treatment and musical habits are unknown. CPD/Clinical Relevance: This paper advises that questioning about wind instrument playing during case history-taking would be beneficial to clinicians. Furthermore, careful clinical monitoring of these patients' teeth during orthodontic treatment should be undertaken.

CBCT: a revolutionary diagnostic aid for endodontic dilemmas

Successful management of endodontic problems is reliant on diagnostic imaging techniques to provide critical information about the teeth under investigation, and their surrounding anatomy. Until recently, most of this core information was obtained from conventional radiographs. The introduction of cone-beam computed tomography (CBCT) specifically dedicated to imaging the maxillofacial region heralds a true paradigm shift from a two dimensional (2D) to a three dimensional (3D) approach to data acquisition and image reconstruction. CBCT systems provide small field of view images at low dose with sufficient spatial resolution for applications in endodontic diagnosis, treatment guidance, and post treatment evaluation. CBCT has been the subject of unparalleled levels of independent research in dental imaging in the area of endodontics. It gives the edge of 3D imaging at lower radiation level in comparison to conventional CT and has helped to treat endodontic cases with external resoption, root canal variations and apical periodontitis providing the size, site and extent accurately. This paper reviews the fundamentals of CBCT and presents the applications of this imaging system in contemporary endodontic practice.

Cone beam computed tomography updated technology for endodontic diagnosis

Cone beam computed tomography has gained acceptance in the endodontic community for assistance with diagnosis, treatment, and evaluation of outcomes. This article reviews a multitude of applications, from basic principles to clinical applications, using specific cases and supporting literature to demonstrate the benefits for both the specialist and general practitioner.

A review of the questions and needs in endodontic diagnosis

The current diversity of opinions in endodontic diagnosis has been a source of interest and academic debate by clinicians and researchers. Currently, no single pulp testing technique can reliably diagnose all pulpal conditions neither it has been proven to be superior in all aspects. Despite improvements of various aspects of this process, there are no historically dramatic changes, or consensus for pulpal status in health or disease in addition to a lack of relative systematic reviews. In this review, the past, present and future most debated and critically questioned issues of endodontic diagnosis are discussed. The aim of this review is to provide insights in future diagnostic modalities and areas for further study in endodontic practice pertinent to diagnosis.

CBCT technology: endodontics and beyond, Part 2

There is a saying that knowledge is power. Without realizing it, 2-D imaging has created a large information gap due to its limitations as a technology resource. As dental professionals, we have relied on this technology while rarely questioning its validity or the quality of information it provided to us. With the advent of 3-D imaging, that information gap has been narrowed. CBCT imaging has stretched our boundaries, allowing for complete and accurate information in all 3 dimensions. This new knowledge is a most powerful force in dentistry that will dynamically change our ideas, diagnoses, and treatment options. It is the author's belief that the implementation of this technology will lead to new innovations and better care in all specialties of dentistry.

AAE and AAOMR joint position statement. Use of cone-beam-computed tomography in endodontics

All radiographic examinations must be justified on an individual needs basis whereby the benefits to the patient of each exposure must outweigh the risks. In no case may the exposure of patients to X-rays be considered "routine", and certainly CBCT examinations should not be done without initially obtaining a thorough medical history and clinical examination. CBCT should be considered an adjunct to two-dimensional imaging in dentistry. Limited field of view CBCT systems can provide images of several teeth from approximately the same radiation dose as two periapical radiographs, and they may provide a dose savings over multiple traditional images in complex cases.

Use of dental radiography among Lithuanian general dentists

OBJECTIVE

To gather information about the radiographic facilities and techniques used by Lithuanian general dentists.

MATERIALS AND METHODS

Questionnaires were sent to all 2879 Lithuanian dental practitioners registered on the Lithuanian Dental Chamber licence registry data list. The questionnaire was made with multiple-choice answers. Respondents were invited to choose the only one category of answer that best fitted their clinical attitude. Questions included in the present survey concerned general and specific information regarding peculiarities of radiographic imaging. Only answers of respondents who are licensed as general dentists were included in this study.

RESULTS

From the 2850 questionnaires mailed 1532 were returned. The response rate was 53.8%. Of the total responses 1431 questionnaires were received from licensed general dentists. Of total 956 dentists practiced in urban and 576 dentists in rural areas. 61.6% of respondents had access to an intra-oral radiographic unit in their practice and 91.5% of them used dental radiography always or often as the diagnostic tool. To support the film packet in the patient's mouth alternatively film holder or patient's finger was used by 48% of respondents, while film holder was used only by 19.3% of dentists.

CONCLUSION

Recently graduated dental practitioners more common used diagnostic radiography in endodontic pathology than dentists with a longer time from graduation. Film holder was not a popular device among general dental practitioners to perform periapical radioraphs. It is important to improve the existing dental curriculum to ensure the necessary competency when using dental radiography and film holders routinely in clinical practice.

Radiographic evaluation of the prevalence of root resorption in a Middle Eastern population

OBJECTIVE

To evaluate radiographically the prevalence of various types of root resorption in different tooth groups in a Middle Eastern population.

METHOD AND MATERIALS

Full-mouth radiographs of 712 patients (19,072 teeth) were evaluated for the presence of root resorption. Two observers evaluated each tooth from at least 2 radiographic projections on periapical films.

RESULTS

Teeth exhibiting root resorption were found in 205 radiographs (28.8%). The most common form of resorption was pulpal infection (71.2%), mainly in mandibular molars ( P< .01) and in patients 45 years and older ( P< .005). Orthodontic pressure resorption was detected in 14.6% of root resorption cases, mainly in maxillary incisors ( P< .01). Impacted tooth or tumor pressure resorption was observed in 10.2% of all cases of resorption, mainly in mandibular molars ( P< .01), and periodontal infection resorption was identified in 3.9% of all resorption cases in all tooth groups ( P > .05). Ankylotic resorption was not found in this survey.

CONCLUSION

The most common types of root resorption in the general population were pulpal infection-related root resorption, orthodontic pressure root resorption, and impacted tooth pressure resorption. It is probable that most are unrelated to traumatic injuries of the teeth.

Dental anatomical anomalies in Asians and Pacific Islanders

Dental anatomical anomalies having a significant impact on endodontic diagnosis and treatment are the talon cusp, tuberculated premolars, three-rooted mandibular molars, and C-shaped molars. Asian and Pacific Islander ethnic groups have the highest percentage of these dental anatomical anomalies compared to the general population. As the population of Asians and Pacific Islanders continues to grow in California and other western states, dentists should be aware of the diagnostic and treatment complexities associated with specific patient groups.

Incidental findings in the maxillofacial area with 3-dimensional cone-beam imaging

INTRODUCTION

The purposes of this study were to evaluate the location, nature, and occurrence of incidental findings in maxillofacial structures on 3-dimensional cone-beam volumetric scans done for dental diagnostic purposes and to look for associations between these findings and symptoms in orthodontic patients.

METHODS

Images from 500 consecutive maxillofacial 3-dimensional scans were examined. The patient sample consisted of 252 orthodontic patients, 172 implant patients, 33 endodontic patients, 34 temporomandibular joint (TMJ) disorder patients, and 10 others.

RESULTS

The overall rate of incidental findings was 24.6% (123 patients of 500). The highest rate of incidental findings was in the airway area (18.2%), followed by TMJ findings (3.4%), endodontic findings (1.8%), and others (1.2%). In the orthodontic group, the incidences were airway findings, 21.4%; TMJ findings, 5.6%; and endodontic lesions, 2.3%. Only 22% of the airway findings, such as mucosal thickness, polyps, and retention cysts, were correlated with clinical signs and symptoms.

CONCLUSIONS

For clinical diagnosis, the data should be interpreted with a full history of clinical signs and symptoms, and with detailed communications with radiological colleagues and other specialists to comprehensively evaluate possible underlying diseases.

[Root canal treatments in a patient with florid cemento-osseous dysplasia]

This article follows the comprehensive dental treatment of a patient who presented with multi periapical radiolucencies on a complete set of periapical radiographs. All the affected teeth were treated and root canal fillings were performed. None of the periapical radiolucencies showed any evidence of a healing process. On a later stage, the lesions have been diagnosed as florid cemento-osseous dysplasia. (In this article the correct diagnosis and treatment will be discussed).

Evaluation of a system for grading the complexity of root canal treatment

AIM

To evaluate the reproducibility of the Restorative Index of Treatment Need (RIOTN) system for grading the complexity of root canal treatment.

METHODOLOGY

The RIOTN system of grading the complexity of root canal treatment was applied to all endodontic referrals to a department of restorative dentistry in a district general hospital within a period of one year. Grading was repeated in 60 randomly selected teeth and weighted kappa analysis was used to test for intra-observer as well as inter-observer agreement with a consultant in restorative dentistry and a vocational trainee (VT).

RESULTS

In all, 152 patients were referred for root canal treatment of 186 teeth within the period of study. Weighted kappa for intra-observer agreement when categorising complexity was 0.636. Weighted kappa for inter-observer agreement with the consultant was 0.570 and that for agreement with the VT was 0.223.

CONCLUSION

The RIOTN system of grading the complexity of root canal treatment was incomplete; with moderate to poor reproducibility.

A clinical classification of the status of the pulp and the root canal system

Many different classification systems have been advocated for pulp diseases. However, most of them are based on histopathological findings rather than clinical findings which leads to confusion since there is little correlation between them. Most classifications mix clinical and histological terms resulting in misleading terminology and diagnoses. This in turn leads to further confusion and uncertainty in clinical practice when a rational treatment plan needs to be established in order to manage a specific pathological entity. A simple, yet practical classification of pulp diseases which uses terminology related to clinical findings is proposed. This classification will help clinicians understand the progressive nature of the pulp disease processes and direct them to the most appropriate and conservative treatment strategy for each condition. With a comprehensive knowledge of the pathophysiology of pain and inflammation in the pulp tissues, clinicians may accomplish this task with confidence.

Cigarette smoking increases the risk of root canal treatment

Few studies have investigated smoking as a risk factor for root canal treatment. We studied the effect of smoking on the incidence of root canal treatment, controlling for recognized risk factors, in 811 dentate male participants in the VA Dental Longitudinal Study. Participants were not VA patients. Follow-up ranged from 2 to 28 years. Root canal treatment was verified on radiographs and evaluated with proportional hazards regression models. Compared with never-smokers, current cigarette smokers were 1.7 times as likely to have root canal treatment (p < 0.001), but cigar and/or pipe use was not significantly associated with root canal treatment. The risk among cigarette smokers increased with more years of exposure and decreased with length of abstinence. These findings suggest that there is a dose-response relationship between cigarette smoking and the risk of root canal treatment.

Dental and oral radiographic findings in first-year university students in 1982 and 2002 in Helsinki, Finland

OBJECTIVE

This study is part of a larger research program, at the Finnish Student Health Service in Helsinki, in which changes in the dental and oral health of first-year university students (born in Helsinki) in the years 1982 and 2002 were compared.

MATERIAL AND METHODS

Panoramic radiographs were taken of 176 students in 1982, mean age 19.8 years (SD+/-0.7), and of 231 in 2002, mean age 20.2 (SD+/-0.7). DMFT index, caries and periapical changes, alveolar bone resorption, wisdom teeth, supernumerary, missing, and persisting deciduous teeth were evaluated from the radiographs. The chi-squared test and non-parametric tests were used to analyze the statistical significance of differences between the study groups and between genders.

RESULTS

The DMFT index diminished from 11.0 (SD +/- 4.2) to 2.9 (SD +/- 3.3) (p < 0.0001). In 2002, 27.9% of the students had a DMFT index of zero (in 1982, 0%, p < 0.000). The mean number of endodontically treated teeth diminished from 0.1 to 0.03 (p < 0.05). The number of impacted wisdom teeth increased in males from mean 0.41 to 0.69 (p < 0.05).

CONCLUSIONS

An improvement in dental health was obvious in the year 2002. The favorable change in DMFT index is a trend that has been going on for several decades in Finland, probably as a result of the use of fluorides and better education in dental hygiene. The change might also be connected with improved general health.

[Diagnostic possibilities of digital volume tomography]

Cone beam computed tomography allows high quality 3D images of cranio-facial structures. Although detail resolution is increased, x-ray exposition is reduced compared to classic computer tomography. The volume is analysed in three orthogonal plains, which can be rotated independently without quality loss. Cone beam computed tomography seems to be a less expensive and less x-ray exposing alternative to classic computer tomography.

Paediatric dentistry in the new millennium: I. Quality care for children

This is the first in a series of articles on paediatric dentistry in the new millennium. The aim of the series is to present a structured approach to the management of children and the common dental problems that are encountered in paediatric patients. Starting with the philosophy of 'quality care', as presented in this article, the series is intended to update readers on modern approaches to both pharmacological and non-pharmacological behaviour management, restorative techniques and the management of common developmental defects that present in both primary and young permanent teeth. Finally, preventive approaches that are easy to administer in a general dental practice will be discussed.

Long-term follow-up of cases considered healed one year after apical microsurgery

A previous report demonstrated 96.8% healing within 1 yr after apical surgery was performed with the surgical operating microscope and Super-EBA as the root-end filling material. The purpose of this paper is to report on the long-term follow-up of those cases that were considered healed at the short term. Clinical examinations were made and radiographs were evaluated 5 to 7 yr after the case had first been considered healed. Criteria for determining healed cases were the same as those used in the first report. Of the 59 roots evaluated, 54 (91.5%) remained healed, whereas 5 (8.5%) showed evidence of apical deterioration.

[Treatment of Baume class IV pulp diseases with calcium hydroxide: a clinical experimental study in Dakar]

The calcium hydroxide used as intracanalar temporary medication in modern endodontics, is the aim of this clinical and radiographic appraisal of endodontic treatment during two sessions (HESS J. C. and all. 1990); on 22 mature permanent teeth with peri apical lesion. In this second Dakar serial study, the mediate disinfection during 6 weeks in average, was followed by a root canal filling for: 11 mono-radicular teeth by compactage of gutta percha, adjusted monocone for 11 pluri-radicular teeth; and so by definitive coronal restoration. The direct magistral preparations used in this study are not expensive, but simple and efficient; our endodontic processing (pre-treatment and treatment) end up at clinical silence and radiographic apical healing in 90.91% of cases after 9 months for 66.67% of root canal filling located at the safety apical limit.

An introduction to meta-analysis within the framework of multilevel modelling using the probability of success of root canal treatment as an illustration

OBJECTIVE

To introduce the statistical methodology of meta-analysis within the framework of multilevel modelling (MLM) using an illustrative example.

BASIC RESEARCH DESIGN

In meta-analysis it is important that the quantitative pooling of study results should be carried out in conjunction with careful consideration of the variation apparent between studies. If statistical heterogeneity is found to be significant, it is due, at least in part, to clinical heterogeneity. It is possible to account for clinical heterogeneity by including covariates that are thought to be responsible, using meta-regression.

CLINICAL SETTING

A total of 38 studies of root canal treatment outcome were identified as being suitable for introducing the meta-analysis methodology. Two covariates were considered for modelling: a 'loose' or 'strict' (loose--incomplete radiographic healing; strict--complete radiographic healing) criterion for judging outcome of treatment and the year in which the study was performed.

RESULTS

There was considerable statistical heterogeneity between the study results. The effect of employing loose criteria for judging success significantly increased the probability of success when compared to employing strict criteria. Furthermore, the variance between studies was significantly reduced when this covariate was included in the modelling process when compared to the variation estimated in the model which did not consider covariates.

CONCLUSION

MLM is a good facilitator for meta-analysis and meta-regression.

Endodontic decisions based on radiographic appearance

Endodontic disease or disease that affects the internal portion of the tooth is a frequently encountered oral problem of the cat and dog. There are many etiologies that can cause the tooth's health and longevity to be adversely affected. Trauma, tooth malformations of either congenital or acquired origin, and bacterial periodontal ascending infections all can lead to pulpal inflammation, necrosis, and tooth death. One must correlate history, physical exam and radiographic impressions of the tooth, and its supporting structures and adjacent teeth in determining proper treatment options and aftercare. Based on extent, timing, and involvement of adjacent structures, resulting pathology of the tooth may be endodontically treated with either a vital pulpectomy, standard root-canal therapy, surgical root-canal therapy, or when the disease is too extensive by extraction. Through a case presentation, we will discuss some of the decisions that enter into the therapy used to treat presenting pathology. It is the authors' intent to present a thought process for deriving a treatment plan to promote healing. There are many ways to achieve this healing, and therefore, there is no right or wrong plan, but rather one that is based on all the presenting factors.

Endodontic radiographs: realities and illusions

Several case reports show how, on occasion, radiographs fail to disclose important realities. The illusions that are presented radiographically have the potential to misdirect diagnosis and treatment as well.

Comparison of different techniques for obturating experimental internal resorptive cavities

Forty extracted maxillary central incisors were instrumented at the working length to a #50 file. The roots were sectioned transversely with a diamond disk at 7 mm from the anatomical apex. At the opening of the root canal of each section, hemicircular cavities were drilled with a specially designed bur. The corresponding root sections were cemented with glue, thus obtaining root canals with similar cavities that simulated internal resorptions. Teeth were embedded in plaster casts to facilitate their handling. The specimens were randomly separated into four groups of 10. The following obturation techniques were evaluated: lateral compaction (group A), hybrid technique (group B), Obtura II (group C), and Thermafil (group D). AH26 was used as the sealer. After obturation, the plaster was removed and the teeth were radiographed in buccolingual and mesiodistal directions to evaluate the quality of the obturation at the IRC. The incisors were then cut with a scalpel at the same level as the previous section, to examine, under a stereomicroscope, the type of material that filled the IRC. Obtura II gave the best results and in most of the specimens obturated with this technique, the IRC were filled mainly with gutta-percha. Statistical analysis of the data indicated that the differences between group C and the other groups were significant (P < 0.05).

Radiographic evaluation of periapical healing after obturation of infected root canals: an in vivo study

AIM

To radiographically compare periapical repair of roots with infected root canals obturated in one-step or with calcium hydroxide (Ca(OH)2) intracanal medication in two steps.

METHODOLOGY

Standardized preoperative periapical radiographs were taken of 72 roots of vital dogs' teeth. All roots were then aseptically instrumented to ISO size 45. As negative controls, 12 roots were aseptically obturated. The remaining roots were infected with dental plaque and closed. Six weeks later, apical periodontitis was radiographically confirmed in the infected roots. The roots were divided into the following groups: group 1, one-step (n = 24); roots were irrigated with 10 cc saline, obturated, and permanently restored. Group 2, Ca(OH)2 (n = 24); roots were treated as in group 1, except that after saline irrigation Ca(OH)2 medicament was placed in the canal 1 week before obturation. Group 3, positive control (n = 12); the roots were irrigated with saline, access permanently closed but canals not obturated. Group 4, negative control (n = 12); previously aseptically obturated roots were permanently restored. After 6 months, standardized postoperative radiographs were obtained. Three independent evaluators blinded to the treatment groups evaluated the preoperative and postoperative radiographs. The evaluators were instructed to rate each root, based on changes on the radiographs, as failed, improved or healed.

RESULTS

Radiographically, the percentage of cases that completely healed were similar for the one-step and Ca(OH)2 groups (35.3% vs. 36.8%). However, the Ca(OH)2 group had fewer failed cases (15.8% vs. 41.2%) and more improved cases (47.4% vs. 23.5%) than the one-step group.

CONCLUSION

Power statistics demonstrated that at 43 cases per group, Ca(OH)2 treatment would be statistically superior to one-step treatment. We consider this number to be clinically important.

Prevalence of periradicular periodontitis associated with crowned teeth in an adult Scottish subpopulation

OBJECTIVE

To examine the periradicular status of crowned teeth in an adult population in Scotland.

DESIGN

Examination of full-mouth periapical radiographs from 319 consecutive adult patients (7596 teeth) attending Glasgow and Dundee Dental Hospitals for clinical examination.

METHODS

The periradicular status of teeth with a crown present was assessed to determine the presence of a radiolucency which may indicate pulpal disease.

RESULTS

63.3% (n = 202) of patients had at least one tooth that was crowned. The total number of crowns assessed was 802, of which 458 (57.1%) were vital preparations, and 87 (19.0%) of these had radiographic signs of periradicular disease. The majority of the teeth (62.0%) had distinct widening of the periodontal membrane space which is considered to be an early sign of periapical disease. 42.9% (n = 344) of the crowned teeth had previous root canal treatment of which 50.8% (175) had evidence of a periradicular radiolucency.

CONCLUSIONS

Pulpal damage may occur during procedures to provide a crown which may require subsequent root canal treatment. Radiographic follow-up of crowned teeth should be undertaken routinely.

Reasons for taking radiographs in general dental practice in Dar-es-Salaam, Tanzania

This study investigated the reasons why dental practitioners at the Muhimbili Dental OPD clinic in Dar-es-Salaam take radiographs. Information was obtained from medical records at the Department of Dental Radiology for an eighteen month period, during which 28,171 patients were seen at the hospital, and of which 2,672 (9.48 per cent) were radiographed. The main reasons for taking radiographs (percentages) was to detect fractures (17.2), tumours (14.1), caries (12.5), impacted teeth (12.2), periodontal disease (11.3), and non-specific dental pain (10.4). Radiographs were also taken for orthodontic (7.0 per cent) and endodontic (6.8 per cent) reasons. Some of the reasons for taking radiographs such as hypersensitive teeth, apicectomy, neuralgia and xerostomia were previously unheard of, indicating an increasing diversity of dental services. In conclusion, there is a need to increase the utilisation of dental radiographs from the present modest level in order to meet the growing need of the increasingly informed dental population in Dar-es-Salaam.

Endodontic pathology leading to implant failure--a case report

This case report documents both the placement of a single implant into an alveolar ridge site and the failure of the implant due to bacterial contamination from an endodontic lesion. After placement of the fixture using osteotomes, the adjacent bicuspid developed periapical pathology following prior crown preparation. This root-end inflammatory process proceeded to involve the mesial surface of the implant. Although endodontic therapy on the devitalized tooth was performed within one week, an osteitis developed around the implant. One month after placement, the fixture had to be removed to prevent additional sequela. The osteotomy site appeared to heal uneventfully, allowing for the placement of a tooth-supported, fixed, partial prosthesis.

Dental problems associated with hypophosphataemic vitamin D resistant rickets

OBJECTIVE

To review a series of cases of hypophosphataemic vitamin D resistant rickets. SUBJECTS INCLUDED: Seventeen cases, aged between 2 years 1 month and 15 years 9 months at first referral, and with an established diagnosis of vitamin D resistant rickets from twelve families were included in the review. Information was drawn from patient records for follow-up periods between 9 months and 20 years 4 months.

SETTING

All subjects had been referred to the Eastman Dental Hospital between 1973 and 1997.

FINDINGS

Abscessed non-carious primary and/or permanent teeth were a presenting feature in eleven of the seventeen cases. Although attrition and exposure of the abnormally formed dentine accounted for the route of infection in primary teeth, the route for microbial invasion of pulpal tissues in permanent teeth remained unexplained in a number of patients. The possible part played by infractures of the enamel as a portal of entry for infection is discussed. Enamel defects were observed in only six patients, in three of whom these changes were limited to the primary dentition. Taurodontism of permanent molar teeth was confirmed as a feature of the condition in the more severely affected male subjects.

Arteriovenous malformation of the mandible: report of a case with a note on the differential diagnosis

Arteriovenous malformations are extremely rare conditions that can result from congenital or acquired abnormalities in the structure of blood vessels; they are potentially fatal. Arteriovenous malformations may be asymptomatic or may show various signs and symptoms including soft tissue swelling, pain, changes in skin and mucosal color, erythematous and bleeding gingiva, bruit, and paresthesia. Radiographically, there are no pathognomonic features. The present case illustrates an arteriovenous malformation in a 16-year-old Hispanic female. The case report is unique because the malformation was previously interpreted as a pathosis of pulpal origin and was initially treated as such, although the tooth showed no gross or radiographic dental caries. A broad view of the diagnostic imaging, radiographic differential diagnosis, treatment, and histopathologic description is also presented.

Periapical radiographic techniques during endodontic diagnosis and treatment

The objective of this article is to describe various radiographic projections which can be used during endodontic therapy. Changes to the angulation of the X-ray beam in relation to the teeth and film can help diagnosis and treatment by producing images which provide additional information not always visible on radiographs taken with standard angulations. For example, changes in angulation can be useful to determine the number and curvature of roots and canals, to identify superimposed roots and to distinguish between anatomical landmarks and apical pathology. Although use of such techniques increases the diagnostic yield of films, it must be appreciated that such views lead to images that are less distinct because of inherent image distortion. Nevertheless, use of the various techniques during endodontics can provide substantial benefit for clinicians in their daily practice.

Detection of anaerobic odontogenic infections by fluorine-18 fluoromisonidazole

Odontogenic infections are a potential risk for patients who receive cervicofacial radiotherapy and should be treated before irradiation. Anaerobic microbial infections are the most common causes. This study assessed the value of the hypoxic imaging agent fluorine-18 fluoromisonidazole (FMISO) in detecting anaerobic odontogenic infections. Positron emission tomography (PET) imaging was performed at 2 h after injection of 370 MBq (10 mCi) of FMISO in 26 nasopharyngeal carcinoma patients and six controls with healthy teeth. Tomograms were interpreted visually to identify hypoxic foci in the jaw. All patients received thorough dental examinations as a pre-radiotherapy work-up. Fifty-one sites of periodontitis, 15 periodontal abscesses, 14 sites of dental caries with root canal infection, 23 sites of dental caries without root canal infection, and seven necrotic pulps were found by dental examination. Anaerobic pathogens were isolated from 12 patients. Increased uptake of FMISO was found at 45 out of 51 sites of periodontitis, all 15 sites of periodontal abscess, all 14 sites of dental caries with root canal infection, all seven sites of necrotic pulp and 15 sites of dental caries without obvious evidence of active root canal infection. No abnormal uptake was seen in the healthy teeth of patients or in the six controls. The diagnostic sensitivity, specificity, positive and negative predictive values, and accuracy of FMISO PET scan in detecting odontogenic infections were 93%, 97%, 84%, 99% and 96%, respectively. 18F-fluoride ion bone scan done in three patients showed that 18F-fluoride ion plays no role in the demonstration of anaerobic odontogenic infection. FMISO PET scan is a sensitive method for the detection of anaerobic odontogenic infections, and may play a complementary role in the evaluation of the dental condition of patients with head and neck tumours prior to radiation therapy.

The diagnostic value of coronal dark-gray discoloration in primary teeth following traumatic injuries

The diagnostic value of dark-gray discoloration of the crown of primary incisors following traumatic injury as a predictor of pulp vitality is controversial. This retrospective study attempted to examine the condition of the pulp of primary incisors with dark-gray discoloration following traumatic injuries. Forty-eight gray caries-free, traumatized primary incisors were examined clinically and radiographically prior to treatment. All teeth included in the study were free of any clinical and/or radiographic signs of pulp necrosis. Crown discoloration was the only clinical or radiographic sign of pulp involvement. Pulpectomy was performed in five teeth within the first month after trauma, in 16 teeth during the second month, 11 teeth between 2 and 6 months, seven teeth between 6 and 12 months, and three teeth after more than a year. In six teeth the time of injury was unknown. Endodontic treatment was initiated without local anesthetic under rubber dam, access to the pulp chamber with high speed, and debridement with a barbed broach. Assessment of the pulp condition was made upon opening the pulp chamber, as follows: Vital-pulp bled when exposed; partial necrosis-bleeding disclosed at the apical area during debridement; total necrosis-no bleeding was observed. Pulp necrosis was found in 37 teeth (77.1%), 10 teeth (20.8%) presented partial necrosis, and only one tooth (2.1%) had a vital pulp. Dark-gray discoloration of primary incisors could be interpreted as an early sign of pulp degeneration that would deteriorate into necrosis. Moreover, discolored primary incisors can be necrotic even without presenting tenderness to percussion, increased mobility, and periapical osteitis.

Odontogenic keratocyst as periradicular radiolucency in the anterior mandible: two case reports

The differential diagnosis of periradicular radiolucencies is broad. Unusual clinical or radiographic features or failure to resolve after quality root canal treatment should be viewed with suspicion and a biopsy specimen should be submitted for histologic examination. Two cases are reported in which the presence of radiolucent lesions could have been mistaken for those of pulpal origin but were subsequently found to be odontogenic keratocysts.

Microcomputed tomography: an advanced system for detailed endodontic research

This study evaluated the value of microcomputed tomography (MCT) for use in endodontic research. Four periodontally involved highly calcified maxillary first molars were extracted and then scanned for evaluation by a MCT system. The teeth were then instrumented, and 2 of the 4 obturated before rescanning for comparison evaluation. Several capabilities of the MCT to advance endodontic research significantly were observed: the ability of the MCT to present accurately the external and internal morphologies of the tooth without tooth destruction; the possibility of showing changes over time in surface areas and volumes of tissues; the ability to assess area and volume changes after instrumentation or obturation; and the capability of evaluating canal transportation following instrumentation or instrumentation and obturation. The tremendous potential of this scientific tool was discussed.

A retrospective clinical and radiologic study of teeth re-implanted following traumatic avulsion

Re-implantation is the recommended therapeutic procedure following traumatic exarticulation of teeth though its long-term prognosis remains controversial. The purpose of the following study was to evaluate the periodontal healing of 33 reimplanted incisors lost after trauma. The sample, which included 24 upper and 9 lower incisors, was divided in two groups: 15 teeth were reimplanted within 1 hour (=Group A) and 21 teeth after 3 hours or more (=Group B). The reimplanted teeth were followed for different radiographic evaluation periods up to 5 years (mean=2-9 years). The results showed a high rate of periodontal healing in Group A (66.7%), while Group B demonstrated a high percentage (83.3%) of both inflammatory and replacement resorption. Thus, even if the whole sample was prevented from drying before reimplantation, the teeth were affected by different rates of root resorption. Among the various prognostic factors suggested by the literature, bacterial contamination during extra-alveolar storage seemed the most critical.