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Paper text:
periodontal diseases can be treated by both non - surgical and surgical therapy . with the evidence of the bacterial specificity in periodontal diseases,1
the non - surgical therapy alone may fail to eliminate the pathogenic bacteria completely because of their location within gingival tissues or in deeper areas inaccessible to periodontal inflammation . to overcome this problem , nowadays a treatment protocol that include the usage of host modulation agents and antimicrobial agents
is being tried as an adjunct to mechanical therapy in the treatment of periodontal diseases . by the introduction of metronidazole ,
a nitromidazole compound developed in france to treat protozoal infections , started the new era of antimicrobial which has highly effective antibacterial spectrum covering most of the strict anaerobic and certain facultative anaerobic bacteria .
it appears to be one of the most useful antimicrobials for the treatment of periodontitis .
numerous controlled studies2 - 7 have demonstrated that metronidazole applied locally or administered orally alone or in combination with mechanical debridement induces a significant reduction in the depth of the periodontal pockets .
these positive results are also supported by systematic reviews.8 - 10 this clinical improvement is often accompanied by a reduction in the number of anaerobic micro - organisms in the subgingival flora of the dental plaque .
several materials have been developed such as bioabsorbable films,11 electrospun poly ( l - lactide - co - d / l - lactide ) fibers,12 hollow fibres gels and dialysis tubes,13 acrylic strips,2 ethyl cellulose strips14 and subgingival irrigations15 to act as a device for the local administration of the antibacterial agent in order to avoid the need for systemic administration which is responsible for adverse effects , failure to comply with treatment and resistance .
5% metronidazole using natural bovine collagen6 when in contact with human gingival crevicular fluid , rapidly forms unresorbable gel that is nonirritant as it is virtually devoid of any immunogenicity .
this preparation in the form of collagen sponges containing 5% metronidazole with the trade name  metrogene 
, an attempt has been made to evaluate the efficacy of 5% metronidazole in collagen device on periodontal status with and without scaling and root planning in chronic periodontitis patients .
twenty volunteers complying to the inclusion criteria were selected from the department of periodontics , royal dental college , chalissery , kerala .
three sites having moderate periodontitis with more than 5 mm periodontal pocket were identified in them . 

both the sexes were included in the age range of 35 - 70 yearsall the volunteers were free from any systemic diseasethe volunteers had not received surgical or non - surgical therapy for the past 6 monthsall the volunteers were asked to abstain from smoking or drinking alcohol during the study periodpregnant women or nursing mothers were not included in the study . 
 
both the sexes were included in the age range of 35 - 70 years all the volunteers were free from any systemic disease the volunteers had not received surgical or non - surgical therapy for the past 6 months all the volunteers were asked to abstain from smoking or drinking alcohol during the study period pregnant women or nursing mothers were not included in the study .
selected sites had periodontal pockets measuring equal to or > 5 mm in different quadrants of the mouth . in each patient , three sites were selected . 

control site ( these sites were treated by scaling and root planing without local drug delivery ( 5% metronidazole)experimental site a ( these sites were treated by local drug delivery ( 5% metronidazole ) without scaling and root planing)experimental site b ( these sites were treated by scaling , root planing and local drug delivery ( 5% metronidazole ) . 
  control site ( these sites were treated by scaling and root planing without local drug delivery ( 5% metronidazole ) experimental site a ( these sites were treated by local drug delivery ( 5% metronidazole ) without scaling and root planing ) experimental site b ( these sites were treated by scaling , root planing and local drug delivery ( 5% metronidazole ) .
selected sites were subjected to baseline clinical examination which includes plaque index,16 gingival index,17 bleeding index18 and measurement of probing pocket depth using william s graduated probe at 0 , 15 and 30 day ( pockets were probed on 0 and 30 day only ) . at baseline after variable assessment , each patient received scaling and root planing .
these sponges were administrated to the apical limit of the pocket using a plastic spatula .

 both the sexes were included in the age range of 35 - 70 yearsall the volunteers were free from any systemic diseasethe volunteers had not received surgical or non - surgical therapy for the past 6 monthsall the volunteers were asked to abstain from smoking or drinking alcohol during the study periodpregnant women or nursing mothers were not included in the study . 
 
both the sexes were included in the age range of 35 - 70 years all the volunteers were free from any systemic disease the volunteers had not received surgical or non - surgical therapy for the past 6 months all the volunteers were asked to abstain from smoking or drinking alcohol during the study period pregnant women or nursing mothers were not included in the study .
selected sites had periodontal pockets measuring equal to or > 5 mm in different quadrants of the mouth . in each patient
control site ( these sites were treated by scaling and root planing without local drug delivery ( 5% metronidazole)experimental site a ( these sites were treated by local drug delivery ( 5% metronidazole ) without scaling and root planing)experimental site b ( these sites were treated by scaling , root planing and local drug delivery ( 5% metronidazole ) . 
 
control site ( these sites were treated by scaling and root planing without local drug delivery ( 5% metronidazole ) experimental site a ( these sites were treated by local drug delivery ( 5% metronidazole ) without scaling and root planing ) experimental site b ( these sites were treated by scaling , root planing and local drug delivery ( 5% metronidazole ) . selected sites were subjected to baseline clinical examination which includes plaque index,16 gingival index,17 bleeding index18 and measurement of probing pocket depth using william s graduated probe at 0 , 15 and 30 day ( pockets were probed on 0 and 30 day only ) . at baseline after variable assessment , each patient received scaling and root planing .
these sponges were administrated to the apical limit of the pocket using a plastic spatula .
controlled delivery devices with solid supports have been used in resorbable or non - resorbable forms .
metronidazole sponges , the subject of the present application , therefore , appears to be a superior choice for the clinician over the other non - surgical modalities currently recommended for the treatment of periodontal diseases .
the clinical parameters like plaque index , gingival index and bleeding index were recorded at  0 day , 15 day and 30 day ( figures 1 - 6 ) . however , the pocket depth was recorded on  0 day and 30 day .
experimental site b : pocket depth  30 day . the mean reduction in plaque score between the control site , an experimental site a and experimental site b showed a significant reduction ( p < 0.01 ) overall ( table 1 ) . comparison of change in plaque score in different groups .
the mean reduction in gingival inflammation between the control site and experimental site a and experimental site b , showed a significant reduction ( p < 0.001 ) ( table 2 ) .
the mean reduction in bleeding index between control and experimental site a and experimental site b showed a significant reduction ( p < 0.001 ) ( table 3 ) .
comparison of probing pocket depth between control and experimental site a , did not show statistically significant differences in pocket depth on 0 - 30 day which is similar to the observations of leeper et al.20 who observed metronidazole therapy was no more effective than root planing alone , where as it contradicts the findings the findings of aziz gandour et al.19 and lindhen et al.14 when it is compared between control and experiment site b , the difference was statistically highly significant , which is consistent with the findings of aziz gandour et al.19 and lindhen et al.14 the mean reduction in pocket depth between experimental site a and experimental site b shows a statistically highly significant difference which strongly supports the findings of aziz gandour et al.19 and hitzig et al.,6 who observed a dramatic reduction in probing pocket depth after metronidazole therapy along with mechanical debridement from 0 day to the end of the study .
local administration of metronidazole along with root planing and no plaque control reinforcement in case of experimental site b appeared to be more effective in reducing pocket depth than oral administration of metronidazole along with root planing and no plaque control . this can be attributed to a greater effectiveness of local delivery of metronidazole rather than its systemic administration in periodontal therapy ( tables 4 and 5 ) .
the mean reduction in plaque score between the control site , an experimental site a and experimental site b showed a significant reduction ( p < 0.01 ) overall ( table 1 ) .
the mean reduction in gingival inflammation between the control site and experimental site a and experimental site b , showed a significant reduction ( p < 0.001 ) ( table 2 ) .
the mean reduction in bleeding index between control and experimental site a and experimental site b showed a significant reduction ( p < 0.001 ) ( table 3 ) .
comparison of probing pocket depth between control and experimental site a , did not show statistically significant differences in pocket depth on 0 - 30 day which is similar to the observations of leeper et al.20 who observed metronidazole therapy was no more effective than root planing alone , where as it contradicts the findings the findings of aziz gandour et al.19 and lindhen et al.14 when it is compared between control and experiment site b , the difference was statistically highly significant , which is consistent with the findings of aziz gandour et al.19 and lindhen et al.14 the mean reduction in pocket depth between experimental site a and experimental site b shows a statistically highly significant difference which strongly supports the findings of aziz gandour et al.19 and hitzig et al.,6 who observed a dramatic reduction in probing pocket depth after metronidazole therapy along with mechanical debridement from 0 day to the end of the study .
local administration of metronidazole along with root planing and no plaque control reinforcement in case of experimental site b appeared to be more effective in reducing pocket depth than oral administration of metronidazole along with root planing and no plaque control . this can be attributed to a greater effectiveness of local delivery of metronidazole rather than its systemic administration in periodontal therapy ( tables 4 and 5 ) .
the major advantage of local application of antibacterial agents as a control release device form is to limit the drug to its target site and thus achieving maximum local concentration .
collagen appears to be a good resorbable support for the immobilization of various drug substances . from the above study
, it can be concluded that the subgingival application of 5% metronidazole in a collagen carrier can be more effective when associated with mechanical debridement in the treatment of chronic periodontitis .
the local tolerance of the sponges , a rapidly resorbable and virtually non - immunogenic material , was excellent , and the risk of developing systemic adverse effects is very unlikely in view of the very small quantity of metronidazole administered .
however , further studies with larger sample size and microbiological assays would be helpful in establishing a concrete inference of these results .
background : a short - term study was undertaken with an objective to demonstrate the therapeutic benefit resulting from the use of metronidazole sponges combined with and without mechanical debridement to mechanical treatment alone in the treatment of periodontal pockets in chronic periodontitis.materials and methods : the study compared the plaque index , gingival index , sulcus bleeding index and probing pocket depth in twenty control sites that received superficial scaling and root planing without the local drug delivery with experimental site a ( 20 sites that received local drug delivery ( 5% metronidazole ) without superficial scaling and root planing ) and experimental site b ( 20 sites received superficial scaling , root planing and local drug delivery ( 5% metronidazole ) at  0  day , 15th day and 30th day.results:there was a significant reduction in plaque index , gingival index , sulcus bleeding index and probing pocket depth in both experimental sites a and b at different intervals from the baseline.conclusion:from the above conclusions , it can be suggested that a single subgingival application of 5% metronidazole in a collagen carrier can be effective , when associated with debridement in the treatment of adult periodontitis .