Elementary Lesions

Elementary Lesions

Introduction :

The mucous membrane of the oral cavity, like the skin, is a covering tissue, an interface between the external environment and the body.  

A careful examination is required to enable the recognition of a lesion of the oral cavity; this is partly related to the nature of the oral environment (repeated trauma, permanent presence of saliva, secondary infection).

Thus, it is very common at the level of the oral mucosa to see the replacement of the easily identifiable primary lesion by a non-specific ulceration.

1. Histological reminder:

       The oral cavity is entirely lined by a mucosa resting on the connective, muscular and bony planes. The mucosa consists of a lining epithelium resting on the lamina propria through a basement membrane.

1. The epithelium:

It is paved, stratified, keratinized or not depending on the location, it includes:

• A germinative cell base backed by the basement membrane (made up of cubic cells and melanocytes, this is the stratum germinatum)
• A Malpighian mucous body (stratum spinosum). The cells are larger and begin to flatten (this phenomenon becomes more pronounced as the cells migrate towards the surface.
• Granular layer (stratum granulosum) found in the keratinized mucosa area.
• Superficial horny layer (stratum corneum) which flakes off.    

2. The chorion:

Loose, richly vascularized connective tissue containing:

• Accessory salivary glands 
• Nerve endings 
• Fibroblasts 
• Lymphocytes, plasma cells, monocytes and macrophages

It is logical to deduce that there are several histological variations related to the topography and physiology of the oral mucosa.

• Masticatory mucosa: attached gingiva, hard palate; or the epithelium is keratinized
• Covering mucosa: cheeks, lips, ventral surface of tongue, floor, soft palate or non-keratinized epithelium
• Specialized mucosa: dorsal surface of the tongue, keratinized, is provided with taste buds

2. Physiology of the oral mucosa: 

As in the skin, the integrity of this epithelium is maintained by the permanent renewal of cells through mitotic divisions of the deep layers and the migration of the cells thus formed, which differentiate, regularly replacing the aged and desquamated layers.

Keratinization of the oral mucosa: corresponds to the appearance of a special protein

 “Keratin” is secreted by keratinocytes and is eliminated at the level of superficial epithelial cells in the oral cavity.

 Turnover: this is the time required for the elimination, by desquamation, of all epithelial cells and their replacement by an equivalent number of cells from 4 to 15 days at the level of the MB.

This keratinization is a physiological phenomenon of defense of the oral mucosa intended to protect the underlying tissues.

3. Basic lesions 
   1. Definition :

The elementary lesion translates the lesion process on a morphological level.

Recognizing an elementary lesion is essential to make the diagnosis, so it begins with a so-called primary lesion, rapidly modified by the presence of saliva, which dissociates the epithelial layers, and incessant movements of the lips, tongue, and teeth, thus reflecting so-called secondary lesions which represent the evolution of the initial process, 

Overall, the terminology used in dermatology to describe skin lesions can be used for oral lesions.

2. Primary elementary lesions  :
   1. The macule: change in the color of the mucous membrane (red)  

It has neither relief nor infiltration, it introduces the notion of erythema, which is a 

pink or red macule that fades with vitropression. This erythema is due to a 

vasodilation or inflammatory hyperemia of the chorion. (Example: stomatitis, glossitis, gingivitis) 

2. Papule: is a raised, circumscribed, solid lesion not containing 

liquid, may be related to increased epithelial mass or 

that of the chorion by edema (for example edema of the lips during the urticarial crisis)

3. The nodule: 

Is a round, protruding bump with a diameter greater than 1 cm, corresponding

to deep cellular infiltration of the chorion, (eg carcinoma)

An infiltration: is a sign of induration found on palpation and must be 

systematically search even if the lesion is flat, it first evokes 

a cancerous lesion occurs. 

4. The vesicle: produces a circumscribed lifting of the oral epithelium of small size (1 to 2 mm), very quickly ruptured at the level of the oral mucosa and it is necessary

 suggest a vesicle in the face of secondary lesions such as ulcerations, 

painful erosions and ulcerated, crusted lesions (eg 

herpes (classic cold sore) with vesicles grouped together in a cluster).

5. The bubble: produces a circumscribed lifting of the epithelium (detachment) covering more than 5 mm and containing a clear liquid, or sero-haematic, like the vesicles the bubbles are quickly ruptured and leave room for erosions with a smooth bottom, bordered by flaps of epithelium often forming a peripheral grayish collar. (Example: erythema multiforme, pemphigus)

The eruption of the blister is accompanied by oral discomfort, burning sensation and dysphagia. Skin involvement is often associated, which should be carefully investigated.

4. Purpura: extravasation of blood outside the vessels of the skin or mucous membranes which can result in either petechiae (red spots which do not disappear with pressure) or bruises.
5. Pustule: They are rarely observed, it is a circumscribed elevation of the skin or mucous membrane and whose content is purulent.
6. Gum: This is a large, protruding, deep, inflamed, suppurative and ulcerated formation (tertiary phase syphilis) 
7. Secondary elementary lesions  : following primary lesions;
8. Pultaceous coatings  : excessive desquamation of the epithelium forms so-called pultaceous coatings, coatings which are easily detached from the mucosa without hemorrhage.
9. Crusts: These are serous formations, transient in the oral cavity due to moistening by saliva, and are observed rather at the level of the lips. They can be purulent or hemorrhagic.
10. Pseudomembranes: consist of sloughed epithelial cells, fibrin, inflammatory cells, microorganisms, and food debris that are easily detached leaving a normal or red surface.
11. Fissures: This is a linear erosion of the epithelium and the upper part of the chorion. It is mainly observed on the tongue, angular cheilitis is a fissure of the corners of the lips.
12. Erosion: is a very superficial solution of continuity of the epithelium, abrading the epithelium, which heals without scarring. It is painful.
13. Ulceration: is a deep loss of substance, interesting 

the entire height of the epithelium and extending to the chorion or even 

beyond that, may also be secondary to a bubble.

7. Atrophy: constitutes a thinning of the oral mucosa that can be encountered in certain candidiasis.
8. Scars: this is newly formed tissue that has repaired a deep loss of substance as in the case of scar tissue.
9. Clinical examination: includes an exo-oral (cervico-facial) examination and an endo-oral examination.

It should be noted that the appearance of lesions in the oral cavity is difficult to recognize due to:

• Histological characteristics of the oral epithelium (rapidly renewing)
• From the nature of the oral environment: repeated microtraumas, permanent presence of saliva, frequency of superinfections, constant heat and chemical and thermal irritation.
• The interrogation must seek:
  • Age 
  • General background
  • Concept of taking medication  
  • Alcohol and tobacco poisoning
  • Notions of recent counting
  • Circumstances and date of appearance of the injuries 
  • Duration, mode of evolution
  • Functional discomfort and pain or notion of burning mucous membrane
  • Concept of recurrence 
  • Previous treatment and their effectiveness
  • General signs

1. Cervico-facial examination: the entire skin covering is explored without omitting the scalp, neurological functions (motor skills, sensitivity), underlying bone structures, and natural orifices (nostrils, external auditory canals). 

Palpation of the cervical lymph node areas is an essential part of the examination.

A general clinical examination of the skin covering in case of suspicion of systemic involvement.     

2. Examination of the oral cavity: under good lighting, use a tongue depressor or mouth mirror to separate the lips, corners of the mouth and tongue, and to visualize areas that are difficult to access with direct vision.

Tweezers and a probe are also needed.

1. Dental examination: by dental formula, CAD index, note periodontal lesions, coronal reconstructions, remove prostheses which sometimes can hide a lesion of the underlying mucosa. The occlusion will also be examined.
2. Mucosa and fibromucosa:

Very methodical, the inspection examines each region of the oral cavity from the outside to the inside even if the lesion appears at first glance.

Spread the lips outwards to clearly visualize the vestibular cul-de-sacs, as well as the folds between the cheek and the gums.

Likewise, the corners of the lips must be unfolded; examination of the palate is facilitated by the mouth mirror.

Palpation of the lips, floor and cheeks can be done in combination with an exo buccal hand. We finish with the examination of the soft palate, tonsils and posterior pharyngeal wall.

3. The tongue: a gentle protraction of the tongue with the tip held by a

compress, is useful for examining the faces and edges, as well as the oral floor.

4. Salivary glands: bilateral parotid and submaxillary regions by inspecting their excretory orifices, and bimanual palpation will also be performed to assess the quality of the saliva. 
5. Main criteria for describing an elementary lesion:

            Will be assessed upon inspection of a lesion:

Criteria	Description
Size
Shape	Regular irregular
Edges	Well limited diffuse lesion
Arrangement	Dispersed grouped confluence
Extension	Localized regional generalized (body)

Palpation will look for pain, bleeding, flexibility or induration at the base, especially when it is an ulceration, and finally its consistency.

3. Additional examinations:

The anamnesis and clinical study make it possible to limit the examinations to the strict minimum in the following:

Local samples in an infectious hypothesis: direct examination and cultures

(virological, bacteriological, mycological);

● Histological examination (biopsy) with, possibly, direct immunofluorescence examination in the case of autoimmune pathology.

● serodiagnosis of bacterial or viral infections: apart from the serodiagnosis of syphilis, they are requested on a case-by-case basis, depending on the diagnosis mentioned.

Conclusion :

The oral cavity can be the site of multiple lesions reflecting the general state of a dermatological pathology and which can be the first stage, hence the importance of knowing how to label them clinically despite the very often detected changes in these lesions and this in relation to the particularity of the oral environment.

Elementary Lesions

  Wisdom teeth can cause infections if not removed.
Dental crowns restore the function and appearance of damaged teeth.
Swollen gums are often a sign of periodontal disease.
Orthodontic treatments can be performed at any age.
Composite fillings are discreet and durable.
Composite fillings are discreet and durable.
Interdental brushes effectively clean tight spaces.
Visiting the dentist every six months prevents dental problems.
 

Elementary Lesions