Orthodontic mini-implant stability under continuous or intermittent loading: a histomorphometric and biomechanical analysis.
Clin Implant Dent Relat Res
; 17(1): 163-72, 2015 Feb.
Article
em En
| MEDLINE
| ID: mdl-23714260
ABSTRACT
BACKGROUND:
Both continuous and intermittent loadings are commonly applied in orthodontics. Clinical experiences and some studies believed that longer duration of force produce more effect (tooth movement, suture expansion, bone remodeling) than transient forces applied with the same magnitude. Alternatively, others indicated that interruption or recovery periods of various periods between loadings cause more bone remodeling and less root resorption. Therefore, which force is more favorable for osseointegration and stability of orthodontic mini-implant remains to be elucidated.PURPOSE:
To evaluate the influence of continuous or intermittent loading on stability of titanium mini-implants. MATERIALS ANDMETHODS:
One hundred ninety-two mini-implants were implanted bilaterally in intraradicular zones of mandibular M1 and P2 in 48 beagles. Loadings were delivered consecutively in continuous group, pauses were given for the last 3 or 7 days of each 2-week reactivation period for intermittent group A and B, respectively. The group unloaded was set as control. After 2, 4, 6 and 8 weeks, the animals were sacrificed and microscopic computerized tomography (µCT), histomorphological observation and pull-out test were applied.RESULTS:
The µCT parameters of mini-implants in four groups were gradually increased with loading time prolonged, while the value of peak load at extraction (F(max)) increased and reached summit at week 6, but dropped slightly at week 8. In continuous group, all measurements were lower than those in intermittent groups at all time points (p < .05), and all values in intermittent group B were higher than those in intermittent group A. Histomorphology observation revealed different degrees of bone remodeling with new bone formation in the peri-implants region in different groups.CONCLUSIONS:
Intermittent loading regimen is more favorable for obtaining stability than continuous force.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Implantes Dentários
/
Implantação Dentária Endóssea
/
Procedimentos de Ancoragem Ortodôntica
/
Mandíbula
Limite:
Animals
Idioma:
En
Revista:
Clin Implant Dent Relat Res
Assunto da revista:
ODONTOLOGIA
Ano de publicação:
2015
Tipo de documento:
Article
País de afiliação:
China