The relationship between masticatory ability, age, and dental and prosthodontic status in an institutionalized elderly dentate population in Qingdao, China

Objectives To identify relationships between masticatory ability and age, and dental and prosthodontic status amongst an institutionalized elderly dentate population in China. Materials and methods A sample of 512 elders living in eight nursing homes in Qingdao was categorized based on a hierarchical dental functional classification system with and without tooth replacements. Masticatory disability scores (MDSs) were analyzed using multiple regression models with only age, and age and dentition variables for participants having ≥ 10 natural and those having < 10 natural teeth in each jaw. Results Overall, associations between MDS and age, number of teeth, and number of teeth replaced by dental prostheses were identified. For participants having ≥ 10 natural teeth in each jaw, no significant associations between MDS and age and dental and prosthodontic status were found. Participants having < 10 natural teeth in each jaw had higher MDS (increasing chewing difficulties) at higher ages . However, when “premolar region sufficient” and “molar region sufficient” were included, MDS was not associated with age, but with these dentition variables. For participants having ≥ 10 teeth including prosthodontically replaced teeth in each jaw, age was the only variable associated with MDS. For participants having < 10 teeth including teeth replaced in each jaw, the significant factor was “premolar region sufficient.” Overall, lower MDS was associated with increasing number of teeth, as well as with increasing number of teeth replaced by dental prostheses. Conclusions In this population of institutionalized dentate elderly, masticatory ability was significantly associated with dental and prosthodontic status. Clinical relevance For institutionalized elderly, having less than ten natural teeth in each jaw is associated with chewing problems. Most important dentition factor is the presence of three to four premolar pairs. Teeth added by partial removable dental prostheses compensate impaired masticatory ability due to tooth loss for 50% compared to natural teeth.