Evaluation of renal osteodystrophy in the dental clinic by assessment of mandibular and phalangeal cortical indices

Mandibular bone imaging assessment in chronic kidney disease: a systematic review and meta-analysis

OBJECTIVE

This systematic review and meta-analysis sought to assess the published research on mandibular cortical and trabecular bone patterns (TBPs) in individuals with chronic kidney disease (CKD) assessed by radiomorphometric index (RMI) analysis on dental radiographs.

STUDY DESIGN

The review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Observational studies that radiographically evaluated cortical and TBPs were analyzed. Risk of bias was assessed according to the Joanna Briggs Institute Critical Appraisal Checklists. Quality of evidence was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation approach. Meta-analysis was performed for studies using dichotomous models or verifying mean differences according to RMI type.

RESULTS

Thirteen papers were included. Mandibular cortical index (MCI) and mental index (MI) were the most frequently evaluated RMIs. For MCI, the estimated risk ratio for decreased bone mineral density indicated by greater porosity in the cortices was 13.7% in CKD patients (95% confidence interval: 0.04-0.24; P = .008) when compared to healthy individuals. MI mean differences in CKD compared to control groups ranged from -0.5100 to -0.2000 mm. However, risk of bias was generally high and quality of evidence was very low.

CONCLUSIONS

MCI and MI are useful screening tests in assessing bone patterns but must be evaluated with caution due to the risk of bias and low quality of evidence in the published literature.

Peculiarities in the panoramic radiograph of patients with secondary hyperparathyroidism due to terminal renal disease: a radiologic controlled comparative study

OBJECTIVES

The present radiological observational controlled study aims to evaluate the impact of secondary hyperparathyroidism (SHPT) due to chronic kidney disease (CKD) as well as the duration of dialysis on the mineralization of the mandible by standardized qualitative evaluation of digital panoramic radiographs.

METHODS

Panoramic radiographs of CKD patients with SHPT and healthy controls were used for the qualitative analysis of the mandibular cortical index (MCI), the trabecular bone pattern (TBP), and calcification and resorption foci. Radiomorphometric indices were correlated to biochemical parameters and the duration of dialysis using the Spearman Rho test. Group comparisons were conducted using the Mann-Whitney U test and Fisher's exact test at a significance level of α ≤ 0.05. Interrater reliability of two physicians was estimated using Cohen's kappa.

RESULTS

Inclusion and exclusion criteria were fulfilled by N = 41 patients. Statistically significant differences in the MCI (p < 0.001) as well as the TBP (p = 0.002) could be detected for the experimental group in comparison to the healthy control group. Focusing on calcification and resorption foci, no statistically significant difference could be detected between the groups (p = 0.244). The level of the detected parathyroid hormone (PTH) significantly correlated with TBP (Rho = 0.338; p = 0.031), while no significant relationship between TBP and the duration of the dialysis could be found.

CONCLUSIONS

Patients with SHPT due to CKD show statistically significant bone changes in the panoramic radiograph, whereby the grade of trabecular bone change correlates to PTH values.

Use of Micro-CT Imaging to Assess Ventral Mandibular Cortical Thickness and Volume in an Experimental Rodent Model With Chronic High-Phosphorus Intake

Adverse effects of high dietary phosphorus on bone health have been observed in both animal and human studies. The aim of the investigation was to examine chronic effects of high phosphorus diet on the apical mandibular cortical thickness and volume in a hystricomorph rodent (Octodon degus) using microcomputed tomography. Male degus were randomly divided into two groups fed by different mineral contents from the age of 12 weeks till the age of 17 months. The micro-CT scanning and wall thickness analysis were applied on the region of the mandible exactly under the apices of the 4th premolar tooth, first molar tooth, and second molar tooth in two animals from each group. General overview and mapping of the ventral mandibular bone thickness revealed pronounced bony mandibular protrusions in all the animals fed a high-phosphorus diet with obvious bone thinning apically to the 4th premolar and first and second molar tooth apices. Mandibular bone volume and thickness located apically to the premolar and molars were statistically significantly smaller/thinner in the group fed by a high phosphorus diet. The thinnest bone measured 0.004 mm, where the mandibular 4th premolar tooth almost perforated the mandibular cortex. Similar studies of metabolic bone disease and its influence on alveolar bone were also published in rats and mice. The influence of different environmental, infectious, or metabolic factors on the growing tooth, alveolar bone formation, and bone pathologies must be done experimentally on growing animals. In contrast, degus have continuously growing dentition, and the effect of any of the above listed factors can be studied in this animal model at any age and for longer time periods.