Bone quality assessment in patients with healing mandibular fracture sites: a computed tomography investigation.

The objective of this retrospective study was to assess the bone quality of healing mandibular fracture sites by measuring the Hounsfield units (HU) on computed tomographic (CT) images obtained presurgery and postsurgery in patients treated with rigid internal fixation (RIF). The HU values of healing fracture sites were compared to those of corresponding nonfractured (control) sites on the opposing side and cervical vertebrae sites in the same patients. In total, 31 patients with 45 mandibular fractures treated with RIF underwent presurgical and postsurgical CT examinations. The scans performed after surgery (1, 3, 6, 12, or 18 months) were taken only when there was a need for radiographic evaluation due to a complaint of discomfort from the patient or when the surgeon needed to verify the postsurgical outcome, and each patient underwent only a single postsurgical CT. At the presurgical CT examination, the HU values were lower in the fracture sites than in the control sites. At 3 months postsurgery, the HU values in the fracture sites had increased as the mandibular bone healed. At 6 months postsurgery, the HU values in the fracture sites were higher than those of the control sites. At 12 and 18 months postsurgery, the HU values of both sites were similar. The HU values of the cervical vertebrae remained constant with time. These results suggest that, in patients who have been treated with RIF for mandibular bone fracture, HU values measured by CT vary across time, expressing the physiologic bone healing process.

The oral manifestations of Huntington's disease: A systematic review of prevalence.

OBJECTIVES: The objective of this systematic literature review was to provide a complete panorama of the oral manifestations of Huntington's disease (HD). MATERIALS AND METHODS: Databases were searched, and original research studies or case report manuscripts up to May 2021 were included using keywords that describe HD combined with words related to oral health; MeSH terms were used exclusively. No time or language restrictions were applied. RESULTS: Twenty-two investigations (12 original articles and 10 case reports) regarding oral manifestations of HD were included. The subjects examined in the selected research articles were dental health, coordination of oral structures, speech, dysphagia, and swallowing alterations. The case reports described dental treatment procedures, oromandibular dyskinesia, dysphagia, and speech alterations. CONCLUSIONS: The oral manifestations of HD were found to be associated with the advance of the disease in that the more severe the HD, the worse the alterations affecting the oral cavity. Dysphagia, dysarthria, masticatory problems, oral health impairment, and choreiform movements involving the tongue and other orofacial muscles were the main manifestations of HD in the oral cavity. The PROSPERO systematic review registration number of this study is CRD42021238934.

Assessment of the correlation between mandibular radiomorphometric patterns and dual-energy X-ray absorptiometry measurements for screening bone mineral density.

The objective of this study was to investigate the correlation between scores for femoral and lumbar spine bone mineral density (dual-energy X-ray absorptiometry [DXA]) and visual, qualitative mandibular bone pattern assess¬ments (mandibular cortical index, trabecular bone pattern, and visual mandibular cortical width) as well as age and body mass index. Three trained observers evaluated 200 panoramic radiographs and 200 femoral and lumbar spine DXA measurements from 100 male and 100 female participants. The κ test showed an acceptable agreement among observers (0.73; P = 0.003). The Shapiro-Wilk test revealed that the variables were not normally distributed, so the Spearman correlation test was used. The mean age of the sample was 60.7 (13.9) years, and 86.0% of the patients were White. There were inverse correlations between the mandibular cortical index and the spine T-score in men, women, and the total sample as well as between the spine Z-score in the total sample. An inverse correlation was observed between the trabecular bone pattern and the spine T- and Z-scores in women and the total sample. The results also showed inverse correlations between the visual mandibular cortical width and all parameters analyzed in men, women, and the total sample except for the femur T-score and spine T- and Z-scores in men. Body mass index was correlated with all DXA parameters. Age was inversely correlated with femur T-scores in men and women but not with spine DXA values in men. The results suggest that qualitative assessments of radiomorphometric patterns on panoramic radiographs correlate with DXA values and therefore are suitable for screening patients at risk of developing low bone mineral density.

Impact of Temporomandibular Joint Discectomy on Condyle Morphology: An Animal Study.

PURPOSE: Temporomandibular disorders lead to parafunctional activity that may alter bone remodeling of mandibular components. This animal study aimed to assess the impact of temporomandibular joint discectomy on condylar bone microarchitecture. MATERIALS AND METHODS: A total of 30 one-month-old Wistar rats were assessed and divided into 3 equal groups (2 test groups and 1 control group) of 10. The first test group underwent disc removal, the second test group underwent disc and condylar cartilage removal, and the 10 remaining rats were analyzed as sham-operated controls, following a split-mouth design. The rats were killed humanely 2 months after surgery, and the respective mandibles were scanned with micro-computed tomography for quantitative morphometric analysis. RESULTS: There were significant differences among the 3 groups analyzed (disc removal, disc and condylar cartilage removal, and sham-operated control) for bone volume fraction (ratio of bone volume to total volume, P = .044), structure model index (P < .001), fractal dimension (P = .024), and porosity (P = .023). In addition, operated and contralateral nonoperated sides significantly differed for all variables in at least 1 of the test groups (P < .05) but not in the control group (P > .05). CONCLUSIONS: Within the limitations of this study, our results suggest that discectomy may lead to alterations of the mandibular condylar morphology.

Computed Tomographic Artifacts in Maxillofacial Surgery.

OBJECTIVES: The present study aimed to present 4 cases and to undertake a systematic review on the current knowledge of the impact of cone beam computed tomographic (CBCT) artifacts on oral and maxillofacial surgical planning and follow-up. METHODS: The MEDLINE (PubMed) database was searched for the period from February 2004 to February 2017, for studies on the impact of CBCT artifacts on surgical planning of oral and maxillofacial surgeries. The PRISMA statement was followed during data assessment and extraction. As a result, data extraction included information regarding: the use of CBCT to plan or follow-up oral and maxillofacial surgeries, presence and type identification of a CBCT artifact, and details on the impact of artifacts on image quality and/or surgical planning. Four cases were selected to illustrate the topic. RESULTS: The search strategy yielded 408 publications in MEDLINE (PubMed). An initial screening of the publications was performed using abstracts and key words. After application of exclusion criteria, a total of 11 studies were finally identified as eligible to be discussed. Studies revealed 3 main types of artifact: beam hardening, streak, and motion artifacts. Most of the studies suggest that artifacts significantly affect oral and maxillofacial surgical planning and follow-up, despite of allowing for identification of metal projectiles in cases of maxillofacial trauma. CONCLUSION: CBCT artifacts have a significant impact on oral and maxillofacial surgical planning and follow-up.

Simple Bone Cyst Mimicking Stafne Bone Defect.

Stafne bone defects (SBDs) are asymptomatic lingual bony defects in mandible, which are usually detected as an incidental finding in plain radiographs. Similarly, simple bone cysts (SBCs) are most frequently found in posterior region of the mandible and also are asymptomatic. However, due to anatomical structures overlap in plain radiographs, there is a possibility of misdiagnosing SBD that often is diagnosed by presumptive diagnosis observed in plain radiograph. This report shows an unusual case that a SBC resembles a SBD.

Comparison of Pixel Values of Maxillary Sinus Grafts and Adjacent Native Bone With Cone-Beam Computed Tomography.

PURPOSE: Pixel values from cone-beam computed tomography (CBCT) are proportional to bone density. This study aimed to correlate and compare pixel values of healed maxillary sinus grafts and adjacent native bone (NB). MATERIAL AND METHODS: This study was conducted on CBCT scan patients referred for maxillary sinus floor augmentation with biphasic calcium phosphate (n = 31). Graft height and width measurements were performed. In addition, mean pixel values were calculated in 3 different regions: NB, sinus graft close to NB (CNB), and sinus graft far from NB (FNB). Micro-CT and histological analyses of bone specimens of a representative case were also performed. RESULTS: Significant correlations were found between CNB and graft height (r = 0.41; P < 0.021); and FNB and graft width (r = 0.519, P < 0.003). In addition, pixel values from both graft groups (CNB and FNB) differed significantly (P < 0.001). Finally, histological sections revealed smaller areas with newly formed bone in the FNB area. CONCLUSIONS: Within the limitations of this study, the present findings suggest that pixel values of sinus grafted areas are directly correlated with the extension of the grafted area.

Osteoporotic alterations in a group of different ethnicity Brazilian postmenopausal women: An observational study.

OBJECTIVES: To compare peripheral bone mineral density alterations among Brazilian postmenopausal women from three ethnic groups considering age and body mass index influence; to correlate their bone mineral density with the mandibular cortical index (MCI); and to evaluate the influence of age, body mass index and ethnicity in the MCI using risk factor analysis. BACKGROUND: Osteoporosis risk is known to have ethical influences. However, little is known about the differences in ethnicity in radiomorphometric indices. MATERIALS AND METHODS: A total of 150 postmenopausal women with different ethnicities (Caucasian, Asian and Afro-descendant) who underwent peripheral dual X-ray absorptiometry and panoramic examination were included. Bone mineral density and MCI were assessed. Adjusted odds ratio analyses were performed on bone density and MCI considering the effect of age, ethnicity and body mass index. The correlations between the MCI and the dual X-ray absorptiometry results were made. RESULTS: Old age, low body mass index and non-Afro-descendant were associated with low bone density. Compared with Afro-descendants, Asians and Caucasians have higher chances of having decreased bone mass. For the MCI, statistical analysis showed that age is the only variable associated with osteoporotic alterations in the mandible. Furthermore, an inverse correlation was found between the MCI and the T-scores. CONCLUSION: Bone density is higher in Brazilian Afro-descendant women than in Caucasians and Asians. Patient's age is associated with bone density and the MCI. The mandibular cortical index is inversely correlated with the peripheral densitometry results within the study ethnic population.

Craniofacial morphology of HIV-positive children and adolescents undergoing antiretroviral therapy: A pilot study.

INTRODUCTION: In this study, we aimed to analyze craniofacial morphology by assessing the skeletal cephalometric profiles of HIV-positive patients receiving antiretroviral therapy. METHODS: For this study, 21 HIV-positive patients aged between 6 and 17 years (study group) were selected and compared with 21 normoreactive patients (control group), paired by sex and age. The patients were also divided into 3 age ranges (6-8, 9-12, and 13-17 years) considering the pubertal growth spurt as the central event. Eighteen (linear and angular) measurements were traced on teleradiographs by using 2 methodologies. The mean values of each measurement were compared between the study and control groups by age range. RESULTS: The majority of the measurements checked in the HIV-positive children and adolescents for the 13-to-17 year age range were diminished, but not enough to generate a statistically significant difference in craniofacial growth. Statistically significant differences (P <0.05) were found only in the inclination of the palatal plane (6-8 years) and the position of the maxilla in the anteroposterior direction (13-17 years). CONCLUSIONS: These results led us to conclude that some cephalometric measurements of HIV-positive children and adolescents may be similar to those of normoreactive subjects.

The use of a computed tomographic application for mobile devices in the diagnosis of oral and maxillofacial surgery.

The aim of the current technical report was to introduce a computed tomographic (CT) application for mobile devices as a diagnostic tool for analyzing CT images. An iPad and an iPhone (Apple, Cuppertino, CA) were used to navigate through multiplanar reconstructions of cone beam CT scans, using an application derived from the OsiriX CT software. Tools and advantages of this method were recorded. In addition, images rendered in the iPad were manipulated during dental implant placement and grafting procedures to follow up and confirm the implant digital planning in real time. The study population consisted of 10 patients. In all cases, it was possible to use image manipulation tools, such as changing contrast and brightness, zooming, rotating, panning, performing both linear and area measurements, and analyzing gray-scale values of a region of interest. Furthermore, it was possible to use the OsiriX application in the dental clinic where the study was conducted, to follow-up the analyzed implant placement and grafting procedures at the chairside. The current findings suggest that technological and practical methods to visualize radiographic images are invaluable resources to improve training, teaching, networking, and the performance of real-time follow-up of oral and maxillofacial surgical procedures. This article discusses the advantages and disadvantages of introducing this new technology in the clinical routine.

Mandibular tori are associated with mechanical stress and mandibular shape.

PURPOSE: The influence of mechanical stimulation on the formation of torus mandibularis (TM) is still poorly understood. We sought to understand the etiology of TMs by investigating the role of parafunctional activity and mandibular morphology on the formation of TMs. MATERIALS AND METHODS: We designed a case-control study for patients attending the dental clinic of the present study (University of São Paulo School of Dentistry, São Paulo, SP, Brazil). Patients presenting with TMs were defined as cases, and those without TMs were defined as controls. Finite element analysis (FEA) was used in 3-dimensional mandibular models to examine the stress distribution in the mandibles with and without TMs. In addition, the associations of mandibular arch shape, mandibular cortical index, and parafunctional activity with the presence of T were assessed using odds ratio analysis. RESULTS: A total of 10 patients with TMs and 37 without TMs were selected (22 men and 25 women, mean age 54.3 ± 8.4 years). FEA showed a stress concentration in the region in which TMs form during simulation of parafunctional activity. The radiographic assessment showed that those with TMs were more likely to have a square-shaped mandible with sharp angles (P = .001) and a normal mandibular cortex (P = .03). The subjects without TMs had a round-shaped mandible with obtuse angles and an eroded mandibular cortex. CONCLUSIONS: Parafunctional activity could be causing the formation of TMs by concentrating mechanical stress in the region in which TMs usually form. Thus, mandibular geometries that favor stress concentration, such as square-shaped mandibles, will be associated with a greater prevalence of TMs.

Transition from failing dentition to full-arch fixed implant-supported prosthesis with a staged approach using removable partial dentures: a case series.

The present retrospective case series is aimed at evaluating a staged approach using a removable partial denture (RPD) as an interim prosthesis in treatment to correct a failing dentition until such time as a full-arch fixed implant-supported prosthesis may be inserted. Eight patients, who had undergone maxillary full-arch rehabilitation with dental implants due to poor prognosis of their dentitions, were analyzed. All treatment included initial periodontal therapy and a strategic order of extraction of hopeless teeth. An RPD supported by selected teeth rehabilitated the compromised arch during implant osseointegration. These remaining teeth were extracted prior to definitive prosthesis delivery. Advantages and drawbacks of this technique were also recorded for the cases presented. Among the advantages provided by the staged approach are simplicity of fabrication, low cost, and ease of insertion. Additionally, RPD tooth support prevented contact between the interim prosthesis and healing abutments, promoting implant osseointegration. The main drawbacks were interference with speech and limited esthetic results. Implant survival rate was 100% within a follow-up of at least 1 year. The use of RPDs as interim prostheses allowed for the accomplishment of the analyzed rehabilitation treatments. It is a simple treatment alternative for patients with a low smile line.

Inflammatory Modifications in Paranasal Sinuses and Ostiomeatal Complex Anatomical Variations in Jet Aircraft Pilots: A Computed Tomography Study.

Introduction Jet aircraft pilots are exposed to huge pressure variation during flight, which affect physiological functions as systems, such as the respiratory system. Objectives The objective of the present investigation was to evaluate inflammatory changes of paranasal sinuses of jet aircraft pilots before and after a jet aircraft training program, using multislice computed tomography (CT), in comparison with a group of nonairborne individuals with the same age, sex, and physical health conditions. A second objective of the present study was to assess the association between the ostiomeatal complex obstruction and its anatomical variations. Methods The study group consisted of 15 jet aircraft pilots participating in the training program. The control group consisted of 41 nonairborne young adults. The 15 fighter pilots were evaluated before initiating the training program and after their final approval for the presence of inflammatory paranasal sinus disease. The ostiomeatal complex anatomical variations and obstructions were analyzed in pilots after the training program. Results Jet aircraft pilots presented higher incidence of mucosal thickening in maxillary sinus and anterior ethmoid cells than controls. Prominent ethmoidal bulla showed significant association with obstruction of the osteomeatal complex. Conclusions Jet aircraft pilots present increased inflammatory disease when compared with nonairborne individuals. The presence of a prominent ethmoidal bulla is associated with ostiomeatal complex obstruction.

Assessment of mandibular cortical index in patients with hepatic cirrhosis: A case-control study.

AIMS: To assess the presence of alterations suggestive of reduced bone mineral density (BMD) by using mandibular cortical index (MCI) in panoramic radiographs of cirrhotic individuals and to evaluate their relationship with other characteristics of hepatic cirrhosis (HC). METHODS AND RESULTS: This is an observational case-control study assessing the medical records of 165 cirrhotic patients matched by sex and age with healthy individuals. MELD (model of end stage liver disease) score, etiology, complications, comorbidities, and serum levels of vitamin D were collected. MCI was used to obtain BMD. Binary logistic regression was used to test associations and the risk estimates were expressed in odds ratio. Most of the sample consisted of men (73.93%) with median age of 56 years old. In the study group, the mean value of MELD was 16.5 and hepatitis C was the main etiology of HC (33.9%). Cirrhotic individuals are 3.99 times more likely to present alterations suggestive of reduced BMD (p < .01). There was no statistical significance in the association of MCI with levels of vitamin D, comorbidities, etiology or cirrhosis complications. CONCLUSIONS: MCI suggestive of reduced BMD is more likely to be identified in panoramic radiographs of cirrhotic individuals than of healthy ones.

Evaluation of a maxillary sinus floor augmentation in the presence of a large antral pseudocyst.

Sinus floor augmentation has been established as a predictable technique to overcome maxillary bone loss. Antral cystic lesions may lead to intrasurgical complications and should be accurately diagnosed. However, antral pseudocysts have recently been described not to be contraindicated for sinus-grafting procedures. The current article sought to report clinical, cone beam computed tomographic, and histologic results of a maxillary sinus floor augmentation, performed with piezoelectric surgery, in the presence of a large antral pseudocyst. Success of graft maturation was confirmed with histologic analysis, which also indicated the absence of inflammatory infiltration in the tissue evaluated. On the basis of our findings, it is possible to perform a predictable treatment based on sinus floor augmentation in the presence of antral pseudocysts. Graft maturation can also be achieved 6 months after sinus-lifting surgeries.

Cone beam computed tomographic evaluation of a maxillary alveolar ridge reconstruction with iliac crest graft and implants.

The present article discusses an atrophic maxilla reconstruction with iliac crest bone block and particulate grafts and dental implants. Onlay block grafts were used to restore bone volume of the anterior maxilla, whereas bilateral sinus floor augmentation was performed using a particulate graft. Ten months after the grafting surgery, 9 dental implants were placed to rehabilitate the case. Results of a 7-year follow-up were obtained clinically and by cone beam computed tomographic images.

Diffusion-weighted magnetic resonance imaging of mandibular bone marrow: do apparent diffusion coefficient values of the cervical vertebrae and mandible correlate with age?

OBJECTIVES: The objective of this investigation was to assess the correlation between the mandible and cervical vertebrae bone marrow apparent diffusion coefficient (ADC), obtained by diffusion-weighted magnetic resonance imaging (DWI), with age; to verify the correlation between ADC values from the mandible and the cervical vertebrae; to describe and assess the differences between ADC values obtained from DWI examinations of distinct mandible areas as well as cervical vertebrae. METHODS: Thirty imaging examinations with DWI for that included the mandible and C1, C2, C3, and C4 vertebrae in the same examination were included. ADC values were collected from 7 distinct areas in the mandible and the cervical vertebrae. Differences between ADC values and non-parametric correlations were performed. RESULTS: A total of 270 regions were assessed. No significant difference was found between ADC values of all areas tested. An inverse correlation was found between C2, C3, and C4 vertebrae ADC values and age. The significant correlation of anatomic area ADC values and age were presented as graphics to verify if the linear trend of ADC values and age are in accordance with the literature CONCLUSIONS: The mandible area that most correlates with the cervical vertebrae, using ADC values, is the posterior trabecular area, below the inferior molars. Also, C2, C3, and C4 vertebrae ADC values inversely correlate with age, which demonstrates the bone qualitative changes in bone composition. ADC values may be useful for the qualitative assessment of bone quality to screen patients at osteoporosis risk.

Correlation among alveolar bone assessments provided by CBCT, micro-CT, and 14 T MRI.

OBJECTIVES: The aim of this study was to evaluate bone mineral adipose tissue (BMAT) volume in 21 alveolar bone specimens, as determined by 14 T MRI, and correlate them to the radiodensity values obtained pre-operatively of regions of interest (ROIs) by cone beam computed tomography (CBCT), and to the bone-volume-to-tissue-volume ratio values obtained by micro-CT, the gold-standard for morphometric data collection. METHODS: Partially edentulous patients were submitted to a CBCT scan, and the radiographic bone densities in each ROI were automatically calculated using coDiagnostiX software. Based on the CBCT surgical planning, a CAD/CAM stereolithographic surgical guide was fabricated to retrieve a bone biopsy from the same ROIs scanned preoperatively, and then to orientate the subsequent implant placement. The alveolar bone biopsies were then collected and scanned using the micro-CT and 14 T MRI techniques. Pearson's correlation test was performed to correlate the results obtained using the three different techniques. RESULTS: In the 21 eligible bone specimens (6 females, 15 males), age (mean age 52.9 years), micro-CT, and 14 T MRI variables were found to be normally distributed (p > 0.05). The strongest-and only statistically significant (p < 0.05)-correlation was found between micro-CT and 14 T MRI values (r = 0.943), and the weakest, between 14 T MRI and CBCT values (r = -0.068). CONCLUSIONS: The findings suggest that 14 T MRI can be used to evaluate BMAT as an indirect marker for bone volume, and that CBCT is not a reliable technique to provide accurate bone density values.