Article • Handbook for Dental Chair Side Assistants Part 1
Dental pathology is the science that investigates the causes, progression and effects of oral health related diseases. Hard tissue pathologies involve bones and teeth. While soft tissue pathologies involve oral and paraoral region epithelia and mesenchyme. Some of the oral pathologies have been discussed.
Developmental defects of lips include cleft lip and palate which causes difficulty in feeding, phonation, micrognathia and also has psychological impact.Double lip is the redundant fold of tissue on mucosal side of lip, more common on upper lip.
Fissured tongue is generally associated with Melkerson Rosenthal syndrome, Down syndrome, Benign migratory glossitis.Geographic tongue/benign migratory glossitis is constantly changing pattern of serpiginous white lines surrounding areas of smooth, depapillated mucosa.
Germinated teeth arise from division of a single tooth germ resulting in incomplete formation of two teeth. Talon cusp which arises lingually from the cingulum areas of a maxillary or mandibular permanent incisors is more prevalent in Rubenstein Taybi syndrome. Supernumerary teeth are more prevalent in permanent dentition and in the maxilla more than mandible.
Environmental enamel hypoplasia is the incomplete or defective formation of the organic enamel matrix of teeth. Amelogenesis imperecta can be hypoplastic, hypocalcified or hypomaturation types.
Natal teeth are teeth present in infant mouth at birth and present a risk of aspiration, trauma to tongue and interfere breastfeeding.
Premalignant lesions are morphplogically altered tissue in which cancerlis more likely to develop than apparent normal counterparts egLeukoplakia, Erythroplakia, Actinic chelitis. The metasatic spread of oral squamous cell carcinoma is mainly through the lymphatics to the ipsilateral cervical lymph nodes
Oral submucousfibrosisIs a precancerous disorder characterized by abnormal collagen depositioncausing burning sensation ,opaque white fibrous bands leading to difficulty in opening mouth. Fibroma is a firm sessile/ predunculate swelling having same color as surrounding tissues. Haemangioma can be capillary or cavernous types.
Salivary gland pathology like mucocele is mainly caused due to trauma and spillage of mucin into the surrounding soft tissues .Xerostomia has multitude of etiological factors like developmental aplasia of salivary glands, radiation, systemic diseases, sjogren syndrome etc.Medications responsible can be antihistamine, antidepressant,antipyschotic, sedatives and anxiolytics, antihypertensive, and anticholinergics.
Inflammation is defined as the local protective response of living mammalian involving host cells,blood vessels. Its cardinal signs are pain(dolor), heat(calor), redness(rubor), swelling(tumor), loss of function(functionlaesa). The acute inflammation response is rapid( lasting less than 2 weeks ) and provides early body reaction delivering leukocytes and plasma proteins to sites of injury , resolves quickly and is usually followed by healing. Chronic inflammation is of prolonged duration in weeks to years in which continuing inflammation ,tissue injury andhealing often by fibrosis proceeds simultaneously.Granulomatous inflammation is a distinctive pattern of chronic inflammation with the presence of activated macrophages with scattered lymphocytes.
Discoloration of teeth can be extrinsic egwith tobacco or intrinsic as with tetracycline ingestion at formative age.
Ectodermal dysplasia is an inherited disorder involving ectodermal structures like skin,hair,nails,teeth and eccrine glands causing trichodysplasia, onchodysplasia, odontodysplasia.
Lichen planus is an autoimmune, mucocutaneous lesion with cutaneous changes on flexor surfaces presenting Wickham’s straie. Erythema multiforme is aglistening,ulcerative,mucocutaneous disease with target lesion/ bull’s eye lesion on the tongue , the palate ,the lips and the gingiva. Congential ichthyosis is a group of monogenetic disorders of cornification sometimes associated with systemic symptoms. The oral manifestations are a high arched palate, periodontits, dental caries and reduced salivary flow. Osteogenesis imperfecta is caused due to mutation in col1a1 on 17q21 &col1a2 on 7q22:1 leads to fragility &porosity of bones, blue sclera and deafness. Pyogenic granuloma is a vascular lesion that occurs on both mucosa and skin and appears as an overgrowth of tissue due to irritation , physical trauma or hormonal factors.