***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: INTRODUCTION Bacterial plaque is an etiologic factor in the development of gingival inflammation and periodontitis . The presence of orthodontic b and s and brackets influences plaque growth and maturation . The purpose s of this research were to monitor microbiologic and periodontal changes after placement of orthodontic attachments over a 1-year period and to link these changes to alterations in cytokine concentrations in the gingival crevicular fluid ( GCF ) . METHODS This longitudinal split-mouth trial included 24 patients .  Supragingival and subgingival plaque composition , probing depth , bleeding on probing , and  GCF flow and composition  were assessed at baseline ( Tb ) and after 1 year ( T52 ) . A statistical comparison was made over time and between the b and ed and bonded sites . Prognostic factors for the clinical reaction at T52 in the GCF at Tb were determined . RESULTS Between Tb and T52 , the pathogenicity of the plaque and all periodontal parameters increased significantly , but intersite differences were not seen , except for bleeding on probing . The cytokine concentrations in the GCF did not differ significantly between the sites or between Tb and T52 . The interleukin-6 concentration in the GCF at Tb was a significant predictive value for the GCF flow at T52 ( P < 0.05 ) . The same relationship was found between the interleukin-8 concentration at Tb and the increase in probing depth at T52 ( P < 0.05 ) . CONCLUSIONS Interleukin-6 and interleukin-8 concentrations before orthodontic treatment were shown to be significant predictive factors for some potential inflammatory parameters during treatment OBJECTIVE To determine whether interleukin 1beta ( IL-1beta ) levels are elevated around microscrew implants that are used as anchorage for tooth movement . MATERIAL S AND METHODS Ten young adults , aged 16.3 + /- 2.5 years and with all four premolars extracted , comprised the study group . Twenty maxillary microscrew implants were placed bilaterally in the alveolar bone between the maxillary second premolars and first molars as anchorage units for distal movement of the maxillary canines . The maxillary canines served as the treatment group , and the microscrew implants were design ated as the implant group . The m and ibular canines were used as controls . Peri-microscrew implant crevicular fluid ( MICF ) and gingival crevicular fluid ( GCF ) were collected at the beginning of tooth movement ( 2 weeks after implant placement ) ; at 24 , 48 , and 168 hours later ; and on days 14 and 21 . An automated enzyme immunoassay was used to measure 1L-1beta in the MICF and the GCF . RESULTS The mean 1L-1beta level in the treatment group was significantly elevated at 24 hours ( P = .003 < .05 ) and 48 hours ( P = .003 < .05 ) , whereas the levels in the control and implant groups did not change significantly during the experimental period . Also , the mean 1L-1beta level of the treatment group was significantly higher that in both the control and implant groups at 24 and 48 hours . CONCLUSIONS The microscrew implants did not demonstrate increased 1L-1beta levels during tooth movement . This supports the concept that microscrew implants might be useful as absolute anchorage devices Background Pain is among the most cited negative effects of orthodontic treatment . Non-steroidal anti-inflammatory drugs seem to be an effective option for minimizing this but can have adverse effects on tooth movement owing to their ability to block prostagl and in synthesis . Acetaminophen has been suggested as the analgesic of choice during orthodontic treatment as it showed no effect on orthodontic tooth movement in previous animal studies . The purpose of this study was to compare the effects of ibuprofen and acetaminophen on the prostagl and in E2 ( PGE2 ) levels of the gingival crevicular fluid ( GCF ) during orthodontic tooth movement in human subjects . Methods A total of 42 patients ( mean age 18 ± 4.5 years ) were r and omly divided into three equal groups : ibuprofen , acetaminophen , and control groups . Maxillary canines were distalized with 150 g of force delivered by NiTi coil springs . GCF sample s were obtained before ( baseline ) and after spring activation at 24 , 48 , and 168 h. The PGE2 content of the GCF was determined using enzyme-linked immunosorbent assay . Results PGE2 levels in all groups increased significantly by 24 and 48 h of force application and decreased to baseline levels by 168 h. No significant difference was found between the acetaminophen and control groups at any time point . There was a significant decrease in PGE2 levels in the ibuprofen group at 24 and 48 h when compared to the other two groups . Conclusions Acetaminophen showed no significant effect on prostagl and in synthesis and may be the safe choice compared to ibuprofen for relieving pain associated with orthodontic tooth movement INTRODUCTION Tooth movement has been studied largely with respect to the force required for tipping when pressure distribution varies along the length of the periodontal ligament . But important factors for effective canine translation include the nature and magnitude of applied stress and the patient 's cell biology . The purpose of this research was to test 3 hypotheses : ( 1 ) the velocity of tooth translation ( v(t ) ) is related to applied stress and growth status , ( 2 ) a threshold of stress accounts for the lag phase , and ( 3 ) v(t ) is correlated with the ratio ( AI ) of 2 cytokines ( IL-1beta , IL-1RA ) measured in gingival crevicular fluid ( GCF ) and stimulated whole blood ( SWB ) . METHODS Continuous maxillary canine retraction stresses of 13 kPa and 4 , 26 , or 52 kPa were applied bilaterally in 6 growing and 4 adult subjects for 84 days . Dental models and GCF sample s were collected at 1- to 14-day intervals . Cytokines were measured in GCF and SWB cell cultures . RESULTS V(t ) was positively related to stress and was higher in growing subjects ( P = .001 ) . It was also related to AI(GCF ) in growers ( R2= 0.56 ) and nongrowers ( R2= 0.72 ) . Canines moved with 52 kPa showed a lag phase , and postlag phase AI(GCF ) was twice that of lag phase AI(GCF ) . Mean v(t ) and associated AI(GCF ) during the postlag phase were nearly double the values for canines moved with 13 and 26 kPa . SWB production of cytokines was dose-dependent . For growing subjects , SWB IL-1RA was correlated with v(t ) ( R = 0.70 - 0.72 ) , and AI(SWB ) and IL-1beta concentrations were correlated with AI(GCF ) ( R = 0.73 - 0.78 ) . CONCLUSIONS V(t ) varied with growth status and stresses < or = 52 kPa ; stresses of < 52 kPa showed no lag phase ; and equivalent stresses yielded subject-dependent differences in v(t ) , which correlated with cytokines in GCF and SWB OBJECTIVE To evaluate whether there is any correlation between ovarian activity and two potent bone-resorbing mediators ( prostagl and in E(2 ) [ PGE(2 ) ] , interleukin-1β [ IL-1β ] ) secreted from the gingival crevicular fluid ( GCF ) during orthodontic tooth movement . MATERIAL S AND METHODS Eighteen female cats were included in this study . Animals were r and omly divided into three groups ( estrous , anestrous , and ovariectomized groups ) , each having six queens . Estrous was induced by administration of 150 IU equine chorionic gonadotropin ( eCG ) to queens of the estrous group . A closed-coil spring , applied with 80 g of tipping force to the canine , was attached between the maxillary canine and mini-implant . GCF was collected on days 0 , 6 , and 12 from each cat to examine PGE(2 ) and IL-1β during orthodontic tooth movement in cats . The PGE(2 ) and IL-1β levels were determined with enzyme-linked immunosorbent assay . RESULTS There was no significant difference ( P > .05 ) between anestrous and the ovariectomized groups in terms of tooth movement on days 6 and 12 of distalization . In contrast , tooth movement in the estrous group was lower ( P < .05 ) than in the remaining two groups ( anestrous and ovariectomized ) . The mean PGE(2 ) and IL-1β levels of the canine teeth of the estrous groups were significantly lower than the remaining two groups on days 6 and 12 ( P < .05 ) of coil spring applications . CONCLUSIONS These results indicate that ovarian activity can affect orthodontic tooth movement and GCF levels of IL-1β and PGE(2 ) in cats 
    Output:
    
Results revealed an immediate release of inflammatory bone-resorptive mediators , IL-1β and TNF-α , where IL-1β increased as early as 1 min to 1 h reaching peak at 24 h while TNF-α increased at 1 h or 1 day .
This was accompanied by a fall in bone-protective mediator ( OPG ) levels at 1 h and 24 h after orthodontic force application .
Continuous forces were accompanied by a decrease in mediator levels after attaining peak levels ( most commonly at 24 h ) while repeated activations in interrupted force upregulated their secretion .
Significant correlations of IL-1β levels with pain intensity , rate of orthodontic tooth movement ( OTM ) and of activity index ( AI ) ( IL-1β/IL-1RA ) with velocity of tooth movement and growth status of individuals have also been deduced .
A greater AI and RANKL/OPG ratio was seen in juveniles as compared to adults or non-growers that were associated with faster rate of OTM in juveniles .