Traditional methods of visualization and detection of oral potentially malignant lesions (OPML) and oral squamous cell carcinoma (OSCC) involve a conventional oral examination (COE) with digital...

Technologies Enable Early and Accurate Oral Cancer Detection

postato da lilyeven12 il 28/06/2018
Categoria: Fumetti e Cartoni Animati - tags: water picker

Traditional methods of visualization and detection of oral potentially malignant lesions (OPML) and oral squamous cell carcinoma (OSCC) involve a conventional oral examination (COE) with digital palpation. Currently, COE is the accepted method to assess the clinical characteristics of OPML under normal clinical light without the use of stains, light filters, or magnification. However, evidence indicates that COE is a poor discriminator of oral mucosal lesions. Many optical adjuncts have been developed to assist the clinician to better visualize and detect oral mucosal abnormalities and to differentiate benign lesions from sinister pathology. Characteristics that should be noted include changes in color, texture, and ulceration and the presence of a persistent swelling. Studies have shown that an annual oral examination carried out by a primary care dentist can detect mucosal abnormalities that are unknown to the patient. Devices utilizing the principles of tissue reflectance, tissue auto-fluorescence, or reflectance spectroscopy have been commercialized as adjunctive aids to COE for the detection of OPML and OSCC, although these devices are equally helpful in determining the nature of other benign mucosal pathology such as oral lichen planus, pigmented lesions, and vascular lesions once the clinician fully understands the basic principles of their use. Although a common feature of these devices is their ease of use, a common unappreciated problem with them is the skill required on behalf of the clinician to interpret their findings, particularly for those devices utilizing fluorescence or spectroscopy approaches. Reflectance Oral mucosal examination has traditionally been undertaken under incandescent yellow light of often inadequate intensity, mounted on an extension arm attached to a dental chair. Anyone who has used a white LED headlight would confirm that the traditional manner of oral examination is ineffective for proper visualization of oral mucosal surfaces and mucosal pathology. The best way to currently undertake a comprehensive head and neck examination is with the use of white LED light, preferably with some form of magnification (typically up to 2.5) with the use of loupes. This enhances both illumination and magnification, resulting in a superior oral examination and an increased opportunity to visualize and detect lesions, improving the net gains from the examination as well as patient care several-fold. A good example of this combination is Orascoptic’s HiRes 2 (2.5x) loupes and Discovery headlight. This combination is closely comparable to more advanced and expensive imaging modalities used by otolaryngologists and head and neck surgeons in tertiary care facilities. Another device that also enhances oral mucosal surfaces is AdDent’s battery operated intraoral LED Microlux DL trans-illuminator with diffused light attachment Dental Chair. Fluorescence Next-level optical adjuncts take advantage of the oral mucosa’s fluorescent characteristics and how they change under different pathological conditions. Devices such as LEDDental’s VELscope, DentalEZ’s Identafi, Forward Science’s OralID, and AdDent’s Bio/Screen all operate by emitting violet or blue excitation light at 405 to 450 nm. In the case of VELscope, OralID, and Bio/Screen, which emit blue light, normal oral mucosa is associated with a pale green fluorescence when viewed through a filter, whereas abnormal tissue is associated with loss of auto-fluorescence, also known as fluorescence visualisation loss, and appears dark. In the case of Identafi, which emits violet (405 nm) light, normal oral mucosa appears blue when viewed through a filter whereas abnormal tissue presents with a dark purple hue dental scaling machine. Auto-fluorescence is a phenomenon whereby an extrinsic light source is used to excite endogenous fluorophores such as certain amino acids, metabolic products, and structural proteins. The fluorophores absorb photons from the exogenous light source and emit lower-energy photons that present clinically as fluorescence. Each fluorophore is associated with specific excitation and emission wavelengths. Assessment of oral mucosal pathology utilizing fluorescence-based optical adjuncts should always occur after a white light examination, as undertaking an auto-fluorescence examination without first noting any soft tissue changes with white light will result in a significant number of false positives and undue referral for biopsy of tissues. In fact, a specific decision-making protocol should be adopted to avoid false positive findings and to enhance the utility of these devices in general dental practice. It should be remembered that vascular, haemorrhagic, and pigmented lesions in addition to areas of exogenous staining such as amalgam tattoos will all lose auto-fluorescence water picker. Applying pressure to the lesion, known as diascopy, can help determine if the lesion is vascular or inflammatory, as both these lesion types will blanch under pressure, whereas haemorrhagic lesions such as petechia or purpura and foreign bodies such as amalgam will not.