ABSTRACT
BACKGROUND: During the orthodontic treatment, the results of related reports on potential risk factors affecting the clinical success rate of miniscrew implants are inconsistent. The influential factors that clinicians concern are not all included in this study, and the conclusions from animal experiments are difficult to apply to clinical practice directly. Therefore, what factors affect the clinical success rate of miniscrew implants need further thorough and systematic research. OBJECTIVE: To investigate the factors that influence the clinical success rate of miniscrew implants used as orthodontic anchorage. METHODS: A total of 114 patients with oral implants, including 42 males and 72 females, aged (19. 26±9. 19) years were included in this study. A total of 253 miniscrew implants were implanted as orthodontic anchorage. The following influential factors were included: Gender, age, vertical skeletal facial pattern, implant site, implant arch, soft tissue type at the implant site, oral hygiene status, diameter and length of the miniscrew implants, implantation method, implantation angle, stress loading timing and intensity, and clinical use. Logistic regression analysis was used to study the correlation between success rate and all variables. Analysis of variance was used to test the effect of each variable on clinical success rate. This trial protocol was approved by the Medical Ethics Committee of Sichuan University. RESULTS AND CONCLUSION: Among 253 successful miniscrew implants, the overall success rate was 88. 54% with an average loading period of 9. 5 months. The average loading period of the 29 failed miniscrew implants was 2. 3 months. The chi-square test, Fisher exact test and Logistic regression revealed that age, oral hygiene, vertical skeletal facial pattern, and implant site were significantly correlated with clinical success rate (P 0. 05). These results suggest that to minimize the failure of miniscrew implants, proper oral hygiene instruction and effective supervision should be given to patients, in particular to those young (< 12 years) high mandibular plane patients.
ABSTRACT
BACKGROUND:Mini-implants are widely applied in the clinical treatment of orthodontics and orthognathics, because they can provide absolute skeletal anchorage. However, the relatively high failure rates have always been their major drawback, and how to improve the success rates of mini-implants becomes the main research direction in recent years. OBJECTIVE:To summarize the factors influencing the stability of mini-implants. METHODS:A computer-based search of Wanfang, VIP and PubMed databases was performed using the keywords of “mini-implants, stability, success rate, osseointegration” in Chinese and English. RESULTS AND CONCLUSION:Mibni-implants are an effective means of anchorage control. In clinics, the factors such as implant design, health status of patients, implantation methods and regions, loading patterns and maintenance after implantation wil al have an influence on the stability and success rates of mini-implants. To improve the success rate of the mini-implants, the selection of appropriate implant area is necessary in clinical applications, for example, thicker cortical bone and higher mini-implants are recommended clinicaly; using reasonable and loading implants, studies have shown that non-scored mini-implants is beneficial to reduce the dropout rate of mini-implants during early orthodontic loading; maintenance during healing periods after implantation is emphasized, and currently, stress loading on the mini-implants is preferred immediately after implantation or earlier, which can have a better success rate.