Oral Pulse Granuloma: Histological Findings by Confocal Laser Scanning Microscopy

Personalized Medicine in Oral Oncology: Imaging Methods and Biological Markers to Support Diagnosis of Oral Squamous Cell Carcinoma (OSCC): A Narrative Literature Review

For decades, oral squamous cell carcinoma (OSCC) has been one of the most prevalent and mortal cancers worldwide. The gold standard for OSCC diagnosis is still histopathology but this narrative multidisciplinary review has the aim to explore the literature about conventional OSCC prognostic indicators related to the pTNM stage at the diagnosis such as the depth of invasion and the lymphovascular invasion associated with distant metastasis as indicators of poor life expectancy. Despite its multifactorial nature and recognizable precursors, its diagnosis at the early stages is still challenging. We wanted to highlight the importance of the screening as a primary weapon that a stomatologist should consider, intercepting all at-risk conditions and lesions associated with OSCC and its early stages. This narrative review also overviews the most promising imaging techniques, such as CT, MRI, and US-echography, and their application related to clinical and surgical practice, but also the most-investigated prognostic and diagnostic tissue and salivary biomarkers helpful in OSCC diagnosis and prognostic assessment. Our work highlighted remarkable potential biomarkers that could have a leading role in the future. However, we are still far from defining an appropriate and concrete protocol to apply in clinical practice. The hope is that the present and future research will overcome these limitations to benefit patients, clinicians, and welfare.

Hyaline ring granuloma of the mouth-A foreign-body reaction that dentists should be aware of: Critical review of literature and histochemical/immunohistochemical study of a new case

Hyaline ring granuloma (HRG) is a rare and atypical foreign-body granulomatous chronic inflammatory condition. Our aim was to make a critical review of the literature cases and also to illustrate histochemical and immunohistochemical findings of a new case. A modified PICO strategy was used. Inclusion criteria were met by case reports and case series with a histologically confirmed diagnosis of HRG, necessarily in mouth or maxillary bones. Exclusion criteria were no access to the full-text paper. The search was done up to 2019, totalizing 231 selected cases in 54 papers. The new case was analyzed through PAS, Azan-Mallory's trichrome, and CD34 and CD68 reactions. HRG is found mainly in the mandible of men, edentulous and prosthesis users, between 51 and 60 years of age, with 0.5-120 months of duration, usually causing edema and pain or discomfort. Endogenous and exogenous theories may be complementary in HRG. Eosinophilic areas could represent particles of vegetal origin, while the hyaline material could be the result of collagen degradation. Considering the material is not always present or even is ring-shaped, we suggest the change from "hyaline ring granuloma" to "granuloma induced by vegetal inoculation."

A novel method for in vivo visualization of the microcirculation of the mandibular periosteum in rats

OBJECTIVE

The periosteum plays an important role in bone physiology, but observation of its microcirculation is greatly limited by methodological constraints at certain anatomical locations. This study was conducted to develop a microsurgical procedure which provides access to the mandibular periosteum in rats.

METHODS

Comparisons of the microcirculatory characteristics with those of the tibial periosteum were performed to confirm the functional integrity of the microvasculature. The mandibular periosteum was reached between the facial muscles and the anterior surface of the superficial masseter muscle at the external surface of the mandibular corpus; the tibial periosteum was prepared by dissecting the covering muscles at the anteromedial surface. Intravital fluorescence microscopy was used to assess the leukocyte-endothelial interactions and the RBCV in the tibial and mandibular periosteum. Both structures were also visualized through OPS and fluorescence CLSM.

RESULTS

The microcirculatory variables in the mandibular periosteum proved similar to those in the tibia, indicating that no microcirculatory failure resulted from the exposure technique.

CONCLUSION

This novel surgical approach provides simple access to the mandibular periosteum of the rat, offering an excellent opportunity for investigations of microcirculatory manifestations of dentoalveolar and maxillofacial diseases.

Foreign body granuloma

Foreign bodies can penetrate soft tissues through open wounds, lacerations or through accidents iatrogenically. Among the commonly encountered foreign bodies encountered due to trauma are of glass, metal and wood in nature. We report a case of a 32 year old male who reported to our clinic, complaining of a small wound in the right upper cheek region intraorally since 1 month. Patient had a history of road traffic accident (RTA) 6 months back.

Photothermal multispectral image cytometry for quantitative histology of nanoparticles and micrometastasis in intact, stained and selectively burned tissues

There is a rapidly growing interest in the advanced analysis of histological data and the development of appropriate detection technologies in particular for mapping of nanoparticle distributions in tissue in nanomedicine applications. We evaluated photothermal (PT) scanning cytometry for color-coded imaging, spectral identification, and quantitative detection of individual nanoparticles and abnormal cells in histological samples with and without staining. Using this tool, individual carbon nanotubes, gold nanorods, and melanoma cells with intrinsic melanin markers were identified in unstained (e.g. sentinel lymph nodes) and conventionally-stained tissues. In addition, we introduced a spectral burning technique for histology through selective laser bleaching areas with nondesired absorption background and nanobubble-based PT signal amplification. The obtained data demonstrated the promise of PT cytometry in the analysis of low-absorption samples and mapping of various individual nanoparticles' distribution that would be impossible with existing assays. Comparison of PT cytometry and photoacoustic (PA) cytometry previously developed by us, revealed that these methods supplement each other with a sensitivity advantage (up to 10-fold) of contactless PT technique in assessment of thin (≤100 μm) histological samples, while PA imaging provides characterization of thicker samples which, however, requires an acoustic contact with transducers. A potential of high-speed integrated PT-PA cytometry for express histology and immunohistochemistry of both intact and stained heterogeneous tissues with high sensitivity at the zepromolar concentration level is further highlighted.