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"Horner, Keith"
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Can preoperative imaging help to predict postoperative outcome after wisdom tooth removal? A randomized controlled trial using panoramic radiography versus cone-beam CT
Objectives
The primary objective of the study was to compare the postoperative complications following surgical removal of impacted third molars using panoramic radiography (PAN) images- and cone-beam computed tomography (CBCT)-based surgeries for “moderate-risk” cases of impacted third mandibular molars. The secondary objective was to compare the reliability of CBCT with that of PAN in preoperative radiographic determination of the position of the third molar, number of roots, and apical divergence.
Materials and methods
A randomized controlled multicenter trial was conducted to compare the surgical complications of PAN- and CBCT-based surgeries of impacted third molars. The sample consisted of impacted third molars from 256 patients with a close relation to the inferior alveolar nerve (IAN). Exclusion criteria were “no risk” and “high risk” of damage to the IAN based on the assessment of the panoramic radiograph. Patients were divided into two groups: the CBCT group (
n
= 126) and the PAN group (
n
= 130). The incidences of IAN sensory disturbance and other postoperative complications were recorded for each group at 7 days after surgery. Statistical analysis (kappa values) was used to compare the diagnoses of five trained dentomaxillofacial radiologists and to relate radiologic diagnoses to perioperative findings. Logistic regression was used to determine whether the imaging modality influenced occurrence of postoperative complications.
Results
Two extractions (1.5 %) in the CBCT group and five (3.8 %) in the PAN group resulted in IAN sensory disturbance (
p
= 0.45). Logistic regression models did not show that CBCT modality decreased postoperative complications following surgical removal of impacted third molars. Yet, CBCT revealed the number of roots and apical divergence of the roots more reliably than panoramic radiographs.
Conclusions
CBCT was not better than panoramic radiography in predicting postoperative complications for moderate-risk cases of impacted third mandibular molars. Nonetheless, a CBCT buccolingual view can accurately confirm the number of roots and root morphology of the third molar better than PAN.
Clinical relevance
For management of postoperative complications for moderate-risk cases of impacted mandibular third molars, careful preoperative radiographic planning followed by an atraumatic surgical approach seems to be valuable, irrespective of the 2D or 3D nature of the preoperative images.
Journal Article
Questionnaire surveys - sources of error and implications for design, reporting and appraisal
Questionnaire surveys of dentists are a commonly used research method which can yield important results. Nevertheless, in order to give reliable information, surveys must be carefully designed to avoid bias. The challenge of planning, designing and implementing a questionnaire study is often underestimated. While headline response rate is commonly used as an indication of survey quality, there are four potential areas of survey error. These are coverage, sampling, measurement and response. These four areas of error are discussed, with examples from the current literature, to assist readers in critically appraising questionnaire studies. We make 12 key recommendations to researchers to help avoid bias in their research; approaches to response enhancement are also considered. Reporting guidelines for questionnaire studies are suggested which improve transparency and assist in understanding of research methodologies and results. We have termed these guidelines: Reporting Items for Surveys and Questionnaires (RISQ). In conclusion, there is no single solution that can guarantee a successful study. Conversely, failure to pay careful attention to any one of many crucial aspects of survey design can be the downfall of an otherwise robust study.Key pointsThe challenge of planning, designing and implementing a questionnaire study is often underestimated.There are four potential areas of survey error; these are coverage, sampling, measurement and response.Failure to pay careful attention to any one of many crucial aspects can be the downfall of an otherwise robust study.
Journal Article
Development and applicability of a quality control phantom for dental cone‐beam CT
Cone‐beam CT (CBCT) has shown to be a useful imaging modality for various dentomaxillofacial applications. However, optimization and quality control of dental CBCT devices is hampered due to the lack of an appropriate tool for image quality assessment. To investigate the application of different image quality parameters for CBCT, a prototype polymethyl methacrylate (PMMA) cylindrical phantom with inserts for image quality analysis was developed. Applicability and reproducibility of the phantom were assessed using seven CBCT devices with different scanning protocols. Image quality parameters evaluated were: CT number correlation, contrast resolution, image homogeneity and uniformity, point spread function, and metal artifacts. Deviations of repeated measurements were between 0.0% and 3.3%. Correlation coefficients of CBCT voxel values with CT numbers ranged between 0.68 and 1.00. Contrast‐to‐noise ratio (CNR) values were much lower for hydroxyapatite (0
Journal Article
Effectiveness of hard inserts in sports mouthguards: a systematic review
Objectives To improve the protective capacity of conventional ethylene-vinyl acetate mouthguards, some authors have suggested reinforcement with a hard material to distribute impact energy more widely. The research question for this systematic review was: 'does the inclusion of a hard insert in mouthguards improve the protection of anterior teeth from a direct blow?'Data sources Three bibliographic databases (PubMed/Medline, Ovid/Embase and the Cochrane CENTRAL databases) were searched up to 20 February 2021. Additional searches included hand searching of key articles and journals.Data selection A systematic search of the literature included studies where the intervention was the incorporation of hard material into sports mouthguards and where the comparator was conventional mouthguard material. Eligibility required the use of anatomical specimens or anatomical analogues which included or represented anterior maxillary teeth. Twelve eligible publications were identified.Data extraction Data extraction was first carried out independently by two reviewers. Discrepancies were resolved by discussion.Data synthesis Results of individual studies were conflicting and methodological diversity created difficulty in making a synthesis of results. All studies employed low-energy impacts that did not represent the potentially high-energy impacts encountered in sport.Conclusion The efficacy of hard inserts in sports mouthguards has not been demonstrated.
Journal Article
Potential neurovascular damage as a result of dental implant placement in the anterior maxilla
Introduction A patient requested dental implant therapy to replace his missing upper left central incisor. Pre-operative cone beam computed tomography (CBCT) imaging revealed a complex neurovascular supply to the anterior maxilla.Discussion Imaging demonstrated accessory neurovascular canals around the nasopalatine foramen which directly communicate with canalis sinuosus. They are, therefore, most likely to carry branches of the anterior superior alveolar nerve and vessels. One of these canals was directly in the path of proposed dental implant placement. A review of the dental literature suggests that such anatomical variation is relatively common. Some authors have proposed that injury to these structures is a cause of intractable pain following dental implant placement. Following discussion with the patient, it was agreed that the provision of an adhesive bridge was a realistic alternative in this case.Conclusion The availability of CBCT imaging in recent years has shown that complex neurovascular anatomy in the anterior maxilla is not uncommon. Evidence is lacking regarding the relevance of this to dental implant placement but it is possible that injury to these structures explains some cases of postoperative intractable pain.
Journal Article
ORCA-EFCD consensus report on clinical recommendation for caries diagnosis. Paper I: caries lesion detection and depth assessment
Objectives
The aim of the present consensus paper was to provide recommendations for clinical practice considering the use of visual examination, dental radiography and adjunct methods for primary caries detection.
Materials and methods
The executive councils of the European Organisation for Caries Research (ORCA) and the European Federation of Conservative Dentistry (EFCD) nominated ten experts each to join the expert panel. The steering committee formed three work groups that were asked to provide recommendations on (1) caries detection and diagnostic methods, (2) caries activity assessment and (3) forming individualised caries diagnoses. The experts responsible for “caries detection and diagnostic methods” searched and evaluated the relevant literature, drafted this manuscript and made provisional consensus recommendations. These recommendations were discussed and refined during the structured process in the whole work group. Finally, the agreement for each recommendation was determined using an anonymous Delphi survey.
Results
Recommendations (
N
= 8) were approved and agreed upon by the whole expert panel: visual examination (
N
= 3), dental radiography (
N
= 3) and additional diagnostic methods (
N
= 2). While the quality of evidence was found to be heterogeneous, all recommendations were agreed upon by the expert panel.
Conclusion
Visual examination is recommended as the first-choice method for the detection and assessment of caries lesions on accessible surfaces. Intraoral radiography, preferably bitewing, is recommended as an additional method. Adjunct, non-ionising radiation methods might also be useful in certain clinical situations.
Clinical relevance
The expert panel merged evidence from the scientific literature with practical considerations and provided recommendations for their use in daily dental practice.
Journal Article
Savings Incentives and OAS/GIS Costs
Le vieillissement de la population canadienne entraînera une hausse des coûts du programme de la Sécurité de la vieillesse/Supplément de revenu garanti (SV/SRG). Dans ce contexte, si l'on augmentait les prestations du programme SV/SRG proportionnellement aux salaires pour maintenir son efficacité dans la lutte contre la pauvreté, le coût du programme, en termes de pourcentage du produit intérieur brut, serait multiplié par deux en 2030. C'est ce scénario que je prends comme point de départ dans cet article. À l'aide d'un modèle de cycle de vie - et en tenant compte de l'interaction entre le niveau des prestations de SV/SRG et le niveau des sommes que les individus épargnent en vue de la retraite -, j'analyse ensuite l'impact, sur les coûts du programme, de divers changements qui pourraient lui être apportés. Mes résultats indiquent, entre autres, qu'augmenter - plutôt que de diminuer - le taux de réduction de 50% de la prestation de SRG réduirait, malgré l'effet d'une telle mesure sur l'épargne, les coûts du programme. /// An aging population will raise the cost of Canada's Old Age Security/Guaranteed Income Supplement (OAS/GIS) programs. If the benefit levels under OAS and GIS were increased in line with wages to maintain their antipoverty effectiveness, the program cost would double by 2030 as a percentage of the gross domestic product. With this scenario as a base, we employ a life-cycle model to explore the effect of program design changes on the cost of benefits, taking into account the interaction between OAS/GIS benefits and private retirement saving. One finding is that, despite savings responses, raising-not lowering-the 50 percent benefit-reduction rate under the GIS would reduce program costs.
Journal Article
Savings Incentives and OAS/GIS Costs
An aging population will raise the cost of Canada's Old Age Security/Guaranteed Income Supplement (OAS/GIS) programs. If the benefit levels under OAS and GIS were increased in line with wages to maintain their antipoverty effectiveness, the program cost would double by 2030 as a percentage of the gross domestic product. With this scenario as a base, we employ a life-cycle model to explore the effect of program design changes on the cost of benefits, taking into account the interaction between OAS/GIS benefits and private retirement saving. One finding is that, despite savings responses, raising-not lowering-the 50 percent benefit-reduction rate under the GIS would reduce program costs. Adapted from the source document.
Journal Article
Savings Incentives and OAS/GIS Costs
An aging population will raise the cost of Canada's Old Age Security/Guaranteed Income Supplement (OAS/GIS) programs. If the benefit levels under OAS and GIS were increased in line with wages to maintain their antipoverty effectiveness, the program cost would double by 2030 as a percentage of the gross domestic product. With this scenario as a base, we employ a life-cycle model to explore the effect of program design changes on the cost of benefits, taking into account the interaction between OAS/GIS benefits and private retirement saving. One finding is that, despite savings responses, raising—not lowering—the 50 percent benefit-reduction rate under the GIS would reduce program costs.
Journal Article
Approaches to Strengthening Canada's Retirement Income System
Canada's retirement income system is considered to be well structured, and it has performed well over the last several decades. The system faces important challenges, though, that threaten its continuing ability to provide Canadians with satisfactory retirement incomes. These challenges include increasing longevity, an aging population declining coverage of the workforce in private pension plans, and weaknesses in individual retirement saving. Concern about the implications of these trends has led to calls for a full review of the system and proposals for new government-sponsored savings institutions. This article provides information and analysis on the challenges facing the system and some of the policy issues that they raise. It also outlines different approaches that could be considered in helping the system to accommodate changing needs, and provides a preliminary analysis of the strengths and weaknesses of the various options. Recent research indicates that low pension coverage is centred on small-employer sectors of the economy, and that large-scale pension plans offer striking advantages over small pension plans and individual savings plans. These findings cast doubt on the likely benefits of trying to encourage higher pension coverage in traditional pension plans. They also suggest that enriched savings incentives would be of limited value. Rather, the research supports the calls for those concerned with reform of the system to look carefully at the possibility of creating new large-scale government-sponsored pension or savings plans. [PUBLICATION ABSTRACT]
Journal Article