Quantitative Ultrasound Analysis of Oral Mucosa: An Observational Cross-Sectional Study

Abstract

(1) Background: Ultrasonography is gaining popularity as a diagnostic tool in the study of the oral mucosa. The precision of ultrasound has made it possible to identify the various layers, based on their echogenicity. The aim of this study was to perform a quantitative analysis of healthy oral mucosa based on the analysis of greyscale, echo levels (dB), and attenuation values (dB/cm). (2) Methods: Thirty-three patients (17 females and 16 males; 58.42 ± 13.29 y.o) were recruited for this study. The images were acquired with the GE Logiq-e R7 with a linear probe at 18 MHz frequency (harmonic). For each tissue (epithelium, rete ridges, connective tissue, muscle, and bone), regions of interest were traced for the analysis of echo levels, grey levels, and attenuation values. One-way ANOVA and pairwise comparison were performed. (3) Results: Three-hundred and thirty images were analyzed. Analysis of echo levels and grey levels showed a significant difference between epithelium and rete ridges (p = 0.001), and between rete ridges and connective tissue (p = 0.001), but not between epithelium and connective tissue (p = 0.831) or connective and muscle layers (p = 0.383). The attenuation values appeared to be specific for each tissue layer (p = 0.001). (4) Conclusions: Quantitative analysis applied to ultrasound imaging of the oral mucosa allows the definition of specific tissue areas.

Keratinized mucosa width assessment at implant sites using high‐frequency ultrasonography

“…This finding corroborates the properties of HFUS in discriminating KM from alveolar mucosa based on the different reflection of the ultrasound waves. This observation is in line with previous studies in dentistry 20,21,24,33 and other medical fields 25,34 describing the ultrasonographic presentation of keratinized and nonkeratinized epithelia. The hyperechoic appearance of the keratinized epithelium compared to the alveolar mucosa is probably due not only to the presence of the keratin layer, but also to the superior thickness of the epithelium in KM compared to non-KM.…”

“…On the other hand, KM width assessment with HFUS does not depend on the color of the soft tissue but rather on the acoustic impedance of the different anatomical structures. 24,37 Previous studies have shown the properties of this technology of assessing the position and thickness of the soft tissue and buccal bone, together with the outcomes of periodontal/peri-implant phenotype modifications. 12,18,19,30 The present study further demonstrated that HFUS can also be used to determine the width of KM at implant sites, that has been conventionally assessed with periodontal probes only.…”

“…Applications of novel high‐frequency ultrasound devices (HFUS) in oral pathology and in the medical field have shown the property of this technology of characterizing the epithelium and the connective tissue, including their thickness, echotexture, and alterations in pathological conditions 21,22 . HFUS visualizes the keratinized epithelium as a thick hyperechoic line, discriminating it from the non‐keratinized alveolar mucosa and the underlying connective tissue layer, that lack of this hyperechoic border 21,23–25 . It can be speculated that HFUS can be employed as an alternative method to the conventional assessment of KM, with the possible advantage of providing a more sensitive measure, that can also take into account the profile/morphology of the soft tissue.…”

“…21,22 HFUS visualizes the keratinized epithelium as a thick hyperechoic line, discriminating it from the non-keratinized alveolar mucosa and the underlying connective tissue layer, that lack of this hyperechoic border. 21,[23][24][25] It can be speculated that HFUS can be employed as an alternative method to the conventional assessment of KM, with the possible advantage of providing a more sensitive measure, that can also take into account the profile/morphology of the soft tissue. In particular, augmented sites often exhibit a bulky soft tissue profile, that may not be accurately captured and quantified with a linear measure.…”

State of the Art in the Diagnosis and Assessment of Oral Malignant and Potentially Malignant Disorders: Present Insights and Future Outlook—An Overview

“…This technique for oral cavity exploration is not widely used, but various applications have been reported in the literature: ranging from the study of periodontal and peri-implant tissues to the clinical and surgical characterization of benign and malignant lesions of the oral mucosa [ 133 , 134 ]. Thanks to the advancement of technology, some recent ex vivo and in vivo studies suggest that high-frequency ultrasound holds the ability to distinguish between tissue layers based on image contrast [ 135 ]. This contrast represents the result of acoustic backscatter, which is directly proportional to the change in density found at the boundaries between tissue layers.…”