A randomized follow-up study of the general health and quality of life of an elderly edentulous population wearing either mandibular two-implant overdentures or conventional dentures

The global greying of society indicates that health care systems face new challenges.  High levels of disability can be reduced through new technologies, health promotion and preventive strategies.  Recent literature has underlined the superiority of mandibular implant overdentures over conventional dentures for patient satisfaction and quality of life. However, it is still not clear whether this benefit has any long-term positive effects on oral and general health, as well as on the quality of life of elderly populations.  Objectives, Hypotheses: We aimed to measure the impact of mandibular two-implant overdentures on the general and oral health quality of life, as well as on oral health and sleep quality of edentulous elders. We tested the null hypothesis that there is no difference in the general and oral health quality of life, as well as, on oral health and sleep quality of those wearing mandibular two-implant overdentures (IODs) and those who wear conventional dentures (CDs), one year following prosthesis delivery.  Methods: In this randomized controlled trial, 255 elders randomly received IODs or CDs, both opposed by conventional maxillary dentures. OHRQoL and perceived general health were measured with the Oral Health Impact Profile (OHIP-20) and the Short Form-36 (SF-36) at baseline and after one year.  Sleep quality and daytime sleepiness were measured with the Pittsburg Sleep Quality global score and the Epworth Sleepiness Scale.  Clinical exams were conducted to evaluate oral health.  Independent variables included sense of coherence and prosthesis type, as well as socio-demographic variables.  Between and within group comparisons were performed using bivariate and multivariate statistical tests. Results: Pre/post treatment differences in OHIP scores were significantly greater for the IOD than the CD group (p<0.05).  Type of treatment and pre-treatment scores were significant contributors to OHRQoL (p<0.0001).  In the CD group, there was a statistically significant decrease in physical component scores (PCS), physical functioning, role physical and bodily pain from baseline to one year follow up, indicating decreased perceived general health. In the IOD group, no statistically significant decrease was seen in SF-36 subscale scores from baseline to one year, except for bodily pain.  The final regression model demonstrated that, after controlling for age, sex, marital status and type of treatment, the OHIP total final and the PCS baseline scores predict PCS final scores (p<0.0001).  No significant correlation between sense of coherence and OHRQoL was detected (r= -0.1; p> 0.05). Elders wearing conventional dentures were almost 5 times more likely to have denture stomatitis than those wearing mandibular two-implant retained overdentures (p < 0.0001).  Elders with low perceived general health had poorer sleep than those with high perceived general health (p<0.05).  Those with low oral health related quality of life were almost 4 times sleepier during the day than those with high OHRQoL (p=0.003, χ2; OR =3.8 CI 1.5 to 9.8).  Regression analysis showed that perceived general health and OHRQoL predict sleep quality (p=0.022 and p=0.001, respectively) and daytime sleepiness (p=0.017 and p=0.005, respectively).  Conclusions:  The results of this study suggest that, in edentulous elders, mandibular two-implant overdentures provide significant improvement in oral health related quality of life and maintain perceived physical health. Implant overdentures may contribute to oral health by reducing oral mucosa trauma and control denture stomatitis. Edentulous elders whose oral health related quality of life is low may also have poor sleep quality.

Keyphrases: Randomized clinical trial, Implant overdenture, General health, Qulity of life, Denture stomatitis, Sleep, Sense of coherence