Frontiers in Dentistry

Relationship between Voxel Value of Cone Beam CT and Hounsfield Unit of CT: Systematic Review and Meta-Analysis

Daryush Goodarzipour, Ahmad Reza Shamshiri, Zahra Khodadadi — Tue, 03 Feb 2026 00:00:00 +0330

This systematic review aims to investigate the relationship between voxel value obtained from Cone Beam Computed Tomography (CBCT) in studies compared to Hounsfield of Multidetector Computed Tomography (MDCT) in homogeneous and heterogeneous samples. A literature search was carried out in the databases PubMed, Scopus, Embase, and Web of Science searching for relevant literature until February 2022 (updated at July 2023). A risk of bias assessment of the studies was performed using a modified checklist based on the Cochrane Collaboration’s tool and the Journal of Biomedical Informatics. The software version 20.104 of MedCalc was used to conduct the meta-analysis of correlation coefficients. Out of 4750 articles in the initial search, 13 met the eligibility criteria. Out of the articles, eight studies were included in the meta-analysis. Both heterogeneous and homogenous samples showed a strong correlation between the voxel value of CBCT and Hounsfield Unit (HU), with high heterogeneity (r=0.900 and 0.998 respectively and I2>70%). Two other meta-analyses were conducted for kVp and voxel size, which showed a high correlation. The 95% confidence interval was used to present the estimated pooled correlation. The strong correlation of voxel value and HU indicates the possible potential of CBCT in radiographic bone density measurement. However, further research is needed to obtain an accurate conversion equation for translating voxel values of CBCT to HU. Calibration of voxel values within each scan using a reference object and consideration of both linear and non-linear regression could improve accuracy.

Accuracy of Grayscale Value in Diagnosis of Odontogenic Keratocyst and Radicular Cyst

Mahdi Niknami, Amir Ali Hoseini, Mahsa Bayati — Tue, 03 Feb 2026 10:17:15 +0330

Objectives: Radicular cyst (RC) and odontogenic keratocyst (OKC) are among the most commonly identified cysts in both the maxilla and mandible. With the advancements in 3D imaging techniques such as cone-beam computed tomography (CBCT), there is an opportunity to thoroughly examine the boundaries of these lesions and quantify the grayscale of CBCT images, known as the grayscale value (GSV). This study investigated the reliability of CBCT GSV in distinguishing between RC and OKC.

Materials and Methods: A total of 60 specimens with confirmed pathological diagnoses of RC and OKC were meticulously selected. Before surgical biopsy of each lesion, CBCT images were obtained and analyzed using Romexis version 2.9.2 software to compute the mean GSV of each lesion. Statistical analysis was then conducted using SPSS version 1.0.0.1406, and a linear, backward regression model was used to analyze the differences in GSV between lesion categories (alpha=0.05).

Results: Upon extracting the mean GSV of the selected sections of each type of lesion, no statistically significant difference was observed between the mean GSVs of the two lesion categories (P>0.05).

Conclusion: The present findings regarding lack of a significant difference in the mean GSV between RC and OKC were substantial, and suggest that the GSV may not be a reliable index for differentiating these cystic lesions from each other, a conclusion that could potentially impact future diagnostic practices.

Association of Dental Status and Dry Mouth with Mental Health in Elderly Patients

Tue, 03 Feb 2026 10:24:26 +0330

Objectives: Psychological disorders are prevalent medical conditions that can negatively affect oral health. Due to the increase in the elderly population, and higher risk of psychological conditions in this age group, this study assessed the association of mental health evaluated by the 28-Item General Health Questionnaire (GHQ-28) and oral health in the elderly patients.

Materials and Methods: Overall, 150 elderly patients aged 60 years and higher presenting to the dental clinic of School of Dentistry, Tehran University of Medical Sciences in 2019 participated in this cross-sectional study. Oral and dental examinations were conducted to assess the dental caries status using the decayed, missing, and filled teeth (DMFT) index, number of existing teeth, and self-reported dry mouth. Sociodemographic status, oral hygiene behaviors, and medical history of the participants were also recorded. The GHQ-28 was used to assess their mental health. Data were analyzed by SPSS version 25 using the correlation tests (alpha=0.05).

Results: Of all the participants, 64 (42.7%) were females, and the age range was 60 to 90 years (mean age: 67.56±6.42 years). The mean total GHQ score was 4±3.8. The DMFT score and number of teeth had significant associations with severe depression and social dysfunction (P<0.05). Dry mouth was directly associated with the total GHQ score and anxiety (P<0.05).

Conclusion: Elderly people with severe depression suffered from poor oral health. Comprehensive oral and dental examination and paying close attention to mental health aspects should be considered in regular dental check-ups and oral health promotion programs for the elderly.

Morphological and Morphometric Analysis of the Incisive Foramen: A Retrospective Study on Dry Human Skulls

Tue, 03 Feb 2026 10:39:34 +0330

Objectives: This study aimed to examine the morphological and morphometric characteristics of the incisive foramen and incisive canal in dry human skulls.

Materials and Methods: The sample consisted of 150 dry adult skulls, with no distinction regarding sex or ethnicity. The analysis included the number of incisive canals within the foramen, their dimensions (area and diameter), and their anatomical connections with the incisive fossa and the nasal cavity.

Results: All incisive canals were found to communicate with the nasal cavity. The most frequently observed configuration was foramina containing two or more canals.

Conclusion: Precise anatomical knowledge about the incisive canal and its foramen is essential for clinical procedures involving the anterior maxilla. Morphological variations in this region may affect surgical access, technique selection, and procedural outcomes.

A Challenging Case of Prosthetic Dental Rehabilitation by a Root-Retained Overdenture Using Intra-Radicular Attachments: A Clinical Report with a Seven-Year Follow-Up

Mahnaz Arshad, Negin Yaghoobi Yaghoobi — Tue, 03 Feb 2026 09:53:17 +0330

Conventional complete dentures cause underlying bone resorption over time, which leads to retention loss and poor adaptation of denture. These complications can be prevented in use of root-supported or tooth-supported overdentures. A tooth-retained overdenture with intra-radicular attachments is recommended in case of insufficient inter-arch space to improve denture retention, stability, function, and support. This study describes a tooth-supported overdenture to gain retention from the canine teeth, and compensate for the limitation in inter-occlusal space. This clinical report helps dental clinicians in selection of the appropriate attachment type in different conditions, and designing a suitable treatment plan. After 7 years of follow-up, no complication was observed.