Doses, Benefits, Safety, and Risks in Oral and Maxillofacial Diagnostic Imaging

Accuracy of measurements on CBCT-generated digital models using different exposure parameters (in vitro study)

INTRODUCTION

Dental imaging comprises a wide range of techniques and modalities, each with different diagnostic features influenced by numerous parameters, all of which contribute to the precision and effectiveness of dental evaluations and treatments. This study examined the dimensional reproducibility of arch measurements from CBCT scans with different voxel sizes and exposure parameters compared to a reference model from Extra-oral scanners (EOS) and how these parameters affected digital matching and diagnostic image quality.

METHODS

A diagnostic observational study of arch dimensions, including inter-canine, inter-premolar, intermolar, arch width and arch length, was conducted on digital models (DMs) created from 65 CBCT scans of a full dentate epoxy maxillary model. The measurements obtained from EOS scans served as the control for the study. Normality was tested with the Shapiro-Wilk test, comparisons used the Kruskal-Wallis test with Bonferroni-adjusted pairwise comparisons for significant results, and data were analysed using IBM SPSS (Version 26.0), with significance set at p < .05.

RESULTS

Significant deviations were revealed among study groups, with group I (smallest voxel size) consistently displaying the lowest values, mean (SD) deviation was reported as 0.01 (0.006) and group IV (lowest kV value) exhibiting the highest deviations, mean (SD) deviation of 0.16 (0.17).

CONCLUSION

Combining a small voxel size (0.12 mm) with high milliampere (8 mA) and kilovoltage (90 kV) settings in CBCT ensured detailed anatomical visualization and accurate linear measurements, crucial for precise dental assessments, and emphasizing the necessity for strict control over CBCT parameters in dental applications.

Evaluation of Third Molar Maturity Index by Cone Beam Computed Tomography in Legal Age Estimation: A Preliminary Study

ABSTRACT

This retrospective study aimed to evaluate the accuracy and applicability of the third molar maturity index (I 3M ) for discriminating Turkish minors from adults, and its relationship with chronological age using cone beam computed tomography (CBCT). A total of 122 CBCT scans of Turkish individuals (55 boys and 67 girls) aged 13 to 23 years were evaluated using the I 3M cutoff value. Chronological age gradually decreased as the I 3M value increased. The overall accuracy was 95.9%. The sensitivity and specificity of this test were 93.5% and 97.4%, respectively. Positive predictive value was 95.6%. The intraclass correlation coefficient values of the I 3M for the intraobserver and interobserver agreements were 0.998 and 0.996, respectively. This study showed relatively higher reproducibility of measurements on CBCT scans than on panoramic radiographs in the literature. Cone beam computed tomography may be advantageous and preferred over panoramic radiographs in distinguishing the legal age threshold of 18 years according to Cameriere's method when a more extensive investigation is needed to support the solution of challenging and uncertain cases in forensic medicine.

The "Dedicated" C.B.C.T. in Dentistry

This position statement represents a consensus of an expert committee composed by the Italian Academy of General Dentistry (Accademia Italiana Odontoiatria Generale COI-AIOG) and Italian Academy of Legal and Forensic Dentistry (Accademia Italiana di Odontoiatria Legale e Forense OL-F) on the appropriate use of cone beam computed tomography (C.B.C.T.) in dentistry. This paper analyzes the use of C.B.C.T. in light of the rapid evolution of volumetric technologies, with the new low- and ultra-low-dose exposure programs. These upgrades are determining an improvement in the precision and safety of this methodology; therefore, the need of a guideline revision of the use of C.B.C.T. for treatment planning is mandatory. It appears necessary to develop a new model of use, which, in compliance with the principle of justification and as low as reasonably achievable (ALARA) and as low as diagnostically acceptable (ALADA), can allow a functional "Dedicated C.B.C.T." exam optimized for the individuality of the patient.

Impact of dentists and equipment in the performing dental imaging examinations: a longitudinal analysis

In this study, we aimed to identify factors associated with performing dental imaging examinations in public health services. Brazilian data at the municipal level (n = 5,564) in two time periods, P0 (2005-2007) and P1 (2014-2016), were collated from health information systems. The increase in the municipal rates of intraoral and extraoral radiographic imaging procedures was the outcome. Changes in the use of clinical procedures and the rates of dentists and equipment were the main predictors. Multiple logistic regression analysis was performed to estimate the adjusted odds ratio (OR). Approximately 35.3% of the Brazilian municipalities increased the dental radiography equipment rate, 9.9% increased the fan-beam computed tomography (CT) equipment rate, and 5.9% increased the magnetic resonance imaging (MRI) equipment rate. In addition, 31.8% increased the periapical/interproximal radiography rate, 10.5% increased the CT rate, and 4.4% increased the MRI rate. Increases in the dental radiography, CT, and MRI rates were associated with higher chances of periapical/interproximal images (OR = 1.90, p < 0.01), face and neck images (OR =1 5.3, p < 0.01), and MR images (OR = 18.1, p < 0.01), respectively. Municipalities that increased the rates of endodontists increased the rates of periapical/interproximal (OR = 2.50, p < 0.01) and occlusal (OR = 1.60, p < 0.01) imaging procedures, and those that increased the rates of radiologists also increased the rates of occlusal (OR = 2.00, p < 0.01) and panoramic (OR = 1.70, p < 0.01) imaging procedures. The implementation of a secondary dental care center, Centro de Especialidades Odontológicas (CEO) was associated with an increase in the chances of performing periapical/interproximal and panoramic radiographic procedures in 1.5 and occlusal radiographic examinations in 2.0. The rates of dentists, equipment, specialized dental centers, and specific dental procedures were associated with the increased use of imaging procedures in dentistry in the Brazilian public health system.

An anthropomorphic maxillofacial phantom using 3-dimensional printing, polyurethane rubber and epoxy resin for dental imaging and dosimetry

OBJECTIVE

The aim of this study was to construct an anthropomorphic maxillofacial phantom for dental imaging and dosimetry purposes using three-dimensional (3D) printing technology and materials that simulate the radiographic properties of tissues.

METHODS

Stereolithography photoreactive resins, polyurethane rubber and epoxy resin were modified by adding calcium carbonate and strontium carbonate powders or glass bubbles. These additives were used to change the materials' CT numbers to mimic various body tissues. A maxillofacial phantom was designed using CT images of a head.

RESULTS

Commercial 3D printing resins were found to have CT numbers near 120 HU and were used to print intervertebral discs and an external skin for the maxillofacial phantom. By adding various amounts of calcium carbonate and strontium carbonate powders the CT number of the resin was raised to 1000 & 1500 HU and used to print bone mimics. Epoxy resin modified by adding glass bubbles was used in assembly and as a cartilaginous mimic. Glass bubbles were added to polyurethane rubber to reduce the CT number to simulate soft tissue and filled spaces between the printed anatomy and external skin of the phantom.

CONCLUSION

The maxillofacial phantom designed for dental imaging and dosimetry constructed using 3D printing, polyurethane rubbers and epoxy resins represented a patient anatomically and radiographically. The results of the designed phantom, materials and assembly process can be applied to generate different phantoms that better represent diverse patient types and accommodate different ion chambers.

Ectopic eruption of the first permanent molar: Predictive factors for irreversible outcome

INTRODUCTION

The present study aimed to analyze possible factors involved in irreversible (IRR) ectopic eruption (EE) of the first permanent molar and explore potential predictors for the IRR outcome.

METHODS

Children aged 4-11 years, with at least 1 EE and who took their first panoramic radiograph before the age of 8 years, were selected in this study. The subjects were assigned to the self-correcting (SC) and IRR groups. Patients' age, sex, distribution of EE, and accompanying dental anomalies were recorded. Eruptive angulation (EA) of the first permanent molar, the grade of root resorption in the second deciduous molar, the magnitude of impaction index (MOII), and horizontal distance were measured on the panoramic radiographs. Chi-square tests and independent-sample t test were used for nominal and continuous variables, respectively. The receiver operative characteristic curve was used to determine the critical value.

RESULTS

A total of 406 children with 634 first permanent molars, presenting EE, were enrolled, with 61.3% of the teeth in the SC group. Sex of children with EE and distribution of EE were not relevant to the IRR outcome. The presence of supernumerary teeth might be a protective factor for the IRR outcome. The increasing severity of root resorption in the second primary molar indicated an IRR outcome. A higher MOII and a larger EA suggested an IRR outcome with moderate-to-high quality. The horizontal distance exhibited debatable results, with a low predictive quality.

CONCLUSION

Close monitoring and early intervention would benefit children with increasing severity of distal atypical resorption in the second primary molar, higher MOII, and larger EA.

Estimation of x-ray radiation related cancers in US dental offices: Is it worth the risk?

OBJECTIVES

The objective of this study was to estimate the possible number of cancer cases produced during 2019 in US dental offices from radiography, estimate the possible reduction in those rates resulting from use of intraoral rectangular collimation and selection criteria, and determine the frequency and quality of website radiation risk information and informed consent forms.

STUDY DESIGN

An analysis of dental radiation examinations in 2014 to 2015 US national survey data, Nationwide Evaluation of X-ray Trends, and National Council on Radiation Protection and Measurements surveys was performed, in addition to an analysis of 2008 to 2020 Journal of Clinical Orthodontics national orthodontic surveys for radiographic examination frequencies. Lifetime attributable cancer risk estimates from US and European studies were used to generate the total dental and orthodontic office cancer totals. In total, 150 offices were examined online for the quality and frequency of risk information in websites and consent forms.

RESULTS

The 2019 estimate for all office cancers is 967. Collimation and selection criteria could reduce this to 237 cancer cases. Most cancers arise from intraoral and cone beam computed tomography examinations, with 135 orthodontic cancers over 21 months (average treatment time). Collimation and selection criteria could reduce this to 68. Only 1% of offices use collimators or informed consent for radiography. The website and consent information were of poor quality.

CONCLUSIONS

Dentists are not following selection criteria or using collimators according to guidelines. Up to 75% of cancer cases could be avoided.

Are recent available blended collagen-calcium phosphate better than collagen alone or crystalline calcium phosphate? Radiotextural analysis of a 1-year clinical trial

OBJECTIVES

The purpose of this study is to compare bone regeneration properties of recently available collagen-calcium phosphate (C-CP) blend as bone substitute (BS) material in oral surgery with calcium phosphate (CP) as well as collagen material (Collagen). Is C-CP better than the classic loose CP, or is it at least equally effective in the jawbone regeneration with the superiority of a coherent consistency?

MATERIALS AND METHODS

This study included 102 patients during 12-month follow-up. All patients underwent the following surgical procedures: sinus lift (52patients) and tooth extraction (50patients). Patients were divided into 3 groups which are as follows: experimental group with C-CP, CP and pure Collagen as control groups. Texture analysis was performed in intra-oral radiographs. Analyses were performed in the MaZda 4.6 software. Average 2444-pixel ROIs were established in the image of BS materials and normal trabecular bone for texture comparison to evaluate the jawbone regeneration process. Four features were calculated and investigated.

RESULTS

Texture analyses revealed that all 4 features described the healing process well. Reference textural value of feature SumOfSqrs < 102.37 was soft tissue, DifEntr < 1.1 was not the bone, Entr < 2.62 was not a bone and LngREmph > 1.8 was soft tissue. For 12 months, bone regeneration was proved by 3 of 4 investigated features. Only Entr indicated to CP remnants in the ROI (p < 0.05).

CONCLUSIONS

This study proves that blended collagen-calcium phosphate as a BS material can bring satisfactory and predictable outcomes in jawbone regeneration.

CLINICAL RELEVANCE

Clinicians can choose a satisfactory and predictable material for bone regeneration treatment.

Attitude in Radiographic Post-Operative Assessment of Dental Implants among Italian Dentists: A Cross-Sectional Survey

There is a lack of evidence in the attitude and prescribing practice of implantologists in dental implant post-operative assessment; therefore, the aims of this cross-sectional study were to investigate these habits and the knowledge about radiographic aspect of retrograde peri-implantitis (RPI) among Italian implantologists. A questionnaire was sent via email to dentists randomly selected from the register of implantology and oral surgery societies. It included three questions: the preferred X-ray after implant placement, the timing of post-operative assessment and the knowledge of the RPI radiographic representation. A final sample of 434 implantologists was included in the study. The majority of them (84.3%) perform a periapical X-ray as control radiograph and picked the correct radiographic representation of RPI (74.3%), without statistically significant differences (p > 0.05) for sex, age, years of working practice and number of implants placed per year. Just 47.7% of dentists perform a control radiograph at prostheses delivery, to establish a proper baseline. A statistically significant difference (p < 0.05) was detectable only for the number of implants placed per year, with dentists placing > 80 implants selecting the correct choice. To the best of authors’ knowledge, this is the first study to report data on attitude of implantologists in radiographic imaging after implant placement.