Relationship Between Age and Palatal Tissue and Gingival Tissue in the Guinea Pig

The Effect of Age and Strain Differences on the Incidence of Restraint-Induced Oral and Gastric Ulcers in Three Strains of Rats

“…Studies carried out recently on rats, mice, or guinea pigs have indicated that there is a reduction with age in the mitotic index of the periodontal ligament as measured by radioautography,30 and that the time taken for cells of the periodontium to double in number is less in young animals than in old.3' There appears to be some doubt as to whether these age changes progress steadily throughout the life of the animal or are restricted to early life.32'33 Estimations of biochemical changes during aging have shown that hexose and tyrosine levels increase with age,34 although the actual amounts vary in different sites in the rodent mucosa. 35 The concentrations of deoxyribonucleic acid and ribonucleic acid in the guinea pig palate have not been shown to vary significantly with age. 36 Whether any of these factors can be implicated in the etiology of oral ulceration produced by restraint will remain equivocal until our understanding of the local and general factors influencing tissue resistance to pathology is more complete.…”