Gingiva - Surface and Microanatomy PDF

Gingiva - Surface anatomy and microanatomy [BDS1] Dr Emily Lu, MClinDent Perio RCS Ed, PhD in Periodontology Clinical Lecturer/ Honorary Consultant in Periodontology Learning outcomes Identify and describe the surface anatomy and microanatomy of the gingiva (GDC outcome 1.1.6) What do you see? What...

Gingiva - Surface anatomy and microanatomy [BDS1] Dr Emily Lu, MClinDent Perio RCS Ed, PhD in Periodontology Clinical Lecturer/ Honorary Consultant in Periodontology Learning outcomes Identify and describe the surface anatomy and microanatomy of the gingiva (GDC outcome 1.1.6) What do you see? What do you see? Macroanatomy of the gingiva Oral mucosa Oral mucosa Ten Cate 2018 Oral mucosa Within the epithelium are several strata (layers): 1. Stratum corneum= keratinised layer 2. Stratum granulosum= granular cell layer 3. Stratum spinosum= prickle cell layer 4. Stratum basale= basal cell layer Ten Cate 2018 Epithelium Keratinised 1. Parakeratinised- superficial cells are dead but retain the nucleus 2. Orthokeratinised- nuceli are lost in epithelium Non-keratinised - examples: labial/ buccal mucosa, ventral surface of tongue, soft palate, alveolar mucosa and FOM - Lining mucosa Orthokeratinised Parakeratinised Epithelial-connective tissue interface Junction between epithelium and CT is wavy Connective tissues ‘extends’ into epithelium (lamina propria) Variation in this junction depending on location and type of mucosa (masticatory vs lining mucosa)Prominent ridges vs short/ broad Connective tissue Lamina propria 1. Papillary layer (closest to epithelial ridges) 2. Reticular layer Cells 1. Fibroblasts 2. Macrophages 3. Mast cells, inflammatory cells, lymphocytes Connective tissue Lamina propria Fibres 1. Collagen -90% type I 2. Elastic fibres Ground substance Vasculature Neural tissues Lymph vessels Principle gingival fibre groups Dentogingival fibres Alveologingival fibres Circular fibres Transeptal fibres LOCATIONS of Keratinised epithelium HARD PALATE GINGIVAE Keratinised epithelium Hard palate Gingiva Alveolar ridge Dorsal surface of tongue Vermillion zone Hard palate Epithelium is (ortho)keratinised Long papillae with thick dense collagenous tissue Tightly bound to underlying bone, immobile Epithelium, lamina propria/ periostium= mucoperiostium (no submucosa) Anterior rugae mucoperiostium Gingiva Clinically Scalloped around teeth, knife-edged Paler pink Stippling = collagen fibres run perpendicular to surface and attach lamina propria to periosteum Attached mucosa = Lamina propria directly attached to underlying periosteum (mucoperiosteum), no submucosa Mucogingival junction Gingival tissues Sulcular epithelium Junctional epithelium Gingival epithelium (Rose, Mealey 2004) Gingival tissues Gingival (oral) epithelium Orthokeratinised, stratified squamous epithelium Impermeable physical barrier Rete ridges Sulcular epithelium No rete ridges (para)keratinised – retained nuclei Junctional epithelium Non-keratinising, stratified squamous Special attachment to tooth- hemidesosomes within the JE, basal lamina produced by epithelial cells= epithelial attachment Fast turnover (2-6 days), vs 1 month for GE In health, the most apical part lies at the CEJ Widest -20-30cells thick coronally, tapers to one cell width apically Permeable Junctional epithelium Epithelial attachment = 2 basal laminae Demosomes and gap junctions Large intercellular spaces permeability: passage of GCF/ defence cells Why is the junctional epithelium important? Key tissue involved in the development and progression of periodontitis JUNCTIONAL EPITHELIUM JE Junctional epithelium ES D PDL AB Gingival tissues Sulcular epithelium Junctional epithelium Gingival epithelium (Rose, Mealey 2004) SUMMARY Surface anatomy/ microanatomy of the oral and gingival tissues: in particular, pls know your anatomical landmarks! [Revise: Ten Cate/ Berkovitz] Different types of epithelium- KT; location Gingival tissues- surface anatomy and histologic features of Gingival epithelium; sulcular epithelium; junctional epithelium