As we all know that ageing has its effects on all the organs, periodontium is no exception to it. Just like ageing affects all others organs and their functions of human body, it also effects the periodontium.
General features of ageing in all tissues are:
- Tissue desiccation.
- Changes in cell permeability.
- Decreased elasticity.
- Decreased reparative capacity.
Age changes affects the following periodontal tissues:
- Gingiva and alveolar mucosa.
- Periodontal ligament.
- Alveolar bone.
Changes in vasculature:
- Arteriosclerosis: It is a frequent finding in ageing individuals. It may be seen in large vessels, vessels in alveolar bone and vessels in periodontal ligament. It also predispose these tissues to other changes like fibrosis, loss of cellularity and focal calcifications. It may also be related to reduced bone metabolism and slower wound healing.
- Loss of ground substance: The reduced oxygen supply associated with decreased blood flow may be related to loss of ground substance. Also, basement membrane is thicker and markedly distinct from the surrounding ground substance in older individuals.
Changes in gingival epithelium:
- The mitotic index of gingival epithelium in humans is not significantly different in older individuals, but there is significant increase in cell density, indicating slower rate of maturation.
- Decreased keretinization.
- Flattening of rete pegs, that leads to loss of stippling.
- Some studies shows that there is migration of junctional epithelium apically, accompanying gingival recession. But according to other animal studies, no apical migration has been noted. Gingival recession is not an inevitable physiologic process of aging but occurs by the combined effects of inflammation or trauma.
- Width of attached gingiva increase
Changes in gingival connective tissue:
- Ageing leads to coarser and denser gingival connective tissue.
- There is increased thickness of collagen fibers and the chemical and physical properties of collagen are altered.
- Decreased rate of synthesis of collagen.
- Increased rate of conversion of soluble to insoluble collagen.
- Increased denaturing temperature of collagen.
- Increased resistance to proteolytic enzymes.
- Increase in thermal contraction of collagen fibers.
- Decrease in in vitro extensibility of collagen fibers.
- Increased tensile strength of collagen fibers.
- Overall greater collagen content.
- Decrease in water content of collagen fibers.
Changes in periodontal ligament:
- The principal fibers of the periodontal ligament are thicker in ageing individuals, thus the well organized bundles are broad and wavy.
- The interfibrillar areas are reduced in size.
- There is decrease in ratio of ground substance to collagen.
- Decrease in organic matrix production.
- Decrease in number of fibroblasts, osteoblasts and cementoblasts.
- Decreased epithelial cell rests of Malassez.
- Increase in number of elastic fibers.
- Staining characteristics of periodontal fibers are altered, that is why even the thick and well organized fiber bundles are less distinct since they contains fewer reticular or argyrophilic fibers, so takes up silver nitrate stain only slightly.
- PDL shows hyaline and chondroid degeneration. It may be related to: decreased blood supply, response to injury, or undetermined effect of ageing.
- Calcified bodies are common in PDL of elderly humans.
Changes in cementum:
- Increase in width of cementum. (A study on 233 single rooted teeth revels that the thickness of cementum increases three-fold between the 11 and 76 years of age, with the greatest increase in apical region.). But the rate of cemental deposition slows down with increasing age.
- Attachment of cementum to dentine may get weakened with age.
- Cemental tears are frequently seen in specimens of ageing individuals .They may be related to age changes in the ground substance of cementum, to reduced vascular supply, or to thickened and less extensible ligament fibers embedded in cementum.
- Increase in surface irregularity, due to accumulation of resorption bays.
Changes in alveolar bone:
- Increase in irregularity of periodontal surface of bone.
- Bone grafts prepared from donors of more than 50 years of age are significantly less osteogenic than that obtained from younger donors.
- Alveolar bone proper shows a darkly stained margin, as an ageing characteristic of bone.
- As there is wear on occlusal surface and at contact points of teeth due to ageing, the vertical (interocclusal) dimension and arch continuity are usually maintained in old age, since the wear is compensated by apposition of bone on the distal surfaces and at the fundus of the sockets.(continuous deposition of cementum at the apex also contribute for the compensation of such wear.)
- Vascularity of bone is decreased with age.
- Osteoporosis is also reported with ageing, but decrease in trabeculation of alveolar bone is more often related to loss of function i.e extraction of the opposite tooth.
Effects of ageing on progression of periodontal disease:
Many such studies show that the effect of age is either non-existent or is clinically insignificant in the increased risk of loss of periodontal support. So, age is not a true risk factor but is an associated factor for periodontitis.
Effect of ageing towards the response to periodontal therapy:
Despite the histologic changes in periodontium due to ageing, there is no difference in its response to non-surgical and surgical treatment.
Ageing might affect other aspects of managing periodontal health, such as risk of root surface caries, as chances of root caries increases with age due to root exposure caused by gingival recession.