Incidência de desfechos protéticos associados à overdenture mandibular retida por quatro mini-implantes: estudo prospectivo aninhado a ensaio clínico randomizado

Nenhuma Miniatura disponível



Título da Revista

ISSN da Revista

Título de Volume


Universidade Federal de Goiás


The use of mini-implants is gaining popularity due to less surgical complexity and advantages for cases of atrophic mandibles, and a new system of mini-implants was recently launched (Straumann Optiloc Mini-Implant System®). Aim: This prospective study is part of a randomized clinical trial and aimed to evaluate the incidence of prosthetic outcomes and associated factors in completely edentulous patients after the insertion of mandibular overdentures retained by four mini-implants. Methods: Completely edentulous individuals using conventional complete dentures were recruited for the installation of four mini-implants for treatment with mandibular overdenture. The study combined two surgery protocols (flapped or flapless) and loading (immediate or delayed). During follow-up, the incidence of prosthetic complications and maintenance events were recorded at scheduled and unscheduled appointments. Independent variables were considered as age, gender, surgery and loading protocol, and ridge form (CAWOOD & ROWEL, 1988). A classification of prosthetic outcome (six-field protocol) (PAYNE et al., 2001) was assessed at the end of the follow-up period. Descriptive statistical analysis was performed, with measurements of incidence rates, as well as Kaplan-Meier survival analysis and Cox regression, considering the significance level of p<0.05. Results: 74 participants were accompanied, with a mean age of 64 years (35-80 years), and total follow-up time varied between 19 and 26 months. There were a total of 182 prosthetic events in 147 consultations, 88 of which (59.87%) were unscheduled. The most frequent event was the need for minor adjustments to the base of the overdenture (incidence of 38), due to sore spots; followed by minor repairs at the base (incidence of 16); total (incidence of 21) or partial (incidence of 11) exchange of matrices; indirect relining (incidence of 21) due to instability; new intraoral capture (incidence of 8); fracture of the overdenture (n = 1) and tooth fracture (n = 1). The outcome of success was attributed to 69 participants (93.2%). The most significant predictor for the incidence of adjustments was the flapless surgery protocol (p=0.011), and the age was the most one for the incidence of total matrix replacement (p=0.031). There was no statistically significant difference in the incidence of other prosthetic complications with regard to gender, loading protocol, or ridge form (p>0.05). Conclusions: There was a high incidence of prosthetic events, but they were considered acceptable and mostly represented by small adjustments or repairs to the overdenture base in the initial period of treatment. The high survival and success rate of the implant and prosthesis shows that this is a favorable treatment option for this follow-up, and it is recommended to establish scheduled appointments for the expected events. Longer follow-ups are recommended to obtain more representative data regarding prosthetic outcomes.