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 Table of Contents  
ORIGINAL RESEARCH REPORT
Year : 2017  |  Volume : 14  |  Issue : 1  |  Page : 42-48

Comparative evaluation of fisiograft (polylactic and polyglycolic acid co-polymer) with open flap debridement (OFD) versus open flap debridement (OFD) alone in the treatment of periodontal intra-bony defects: A clinical and radiographic study


1 Department of Periodontics and Implantology, Saraswati Dhanwantari Dental College and Hospital and Postgraduate Research Institute, Parbhani, Maharashtra, India
2 Department of Periodontics and Implantology, SMBT Dental College and Hospital, Sangamner, Maharashtra, India
3 Department of Oral Medicine and Radiology, Saraswati Dhanwantari Dental College and Hospital and Postgraduate Research Institute, Parbhani, Maharashtra, India
4 Department of Periodontics and Implantology, CSMSS Dental College and Hospital, Aurangabad, Maharashtra, India

Date of Web Publication30-Jan-2017

Correspondence Address:
Abhishek Singh Nayyar
44, Behind Singla Nursing Home, New Friends' Colony, Model Town, Panipat - 132 103, Haryana
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/2468-6859.199171

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  Abstract 

Background: Among treatment modalities, grafting of biomaterials/bone substitutes has been used with varying success to accomplish the reconstruction of the lost periodontal attachment apparatus. Biodegradable polymers, especially those belonging to the family of polylactic acid (PLA) and polyglycolic acid (PGA), are playing an increasingly important role in bone reconstructive procedures. The aim of this study was to evaluate the clinical outcome of reconstructive surgery in human deep intrabony defects with the use of fisiograft (polylactic and PGA copolymer) with open flap debridement (OFD) versus OFD alone in the treatment of periodontal intrabony defects. Materials and Methods: Thirty 2- or 3-walled intrabony defects were treated in 15 (ten male and five female) patients with a mean age of 50.4 years. All had completed nonsurgical treatment and a period of supportive periodontal therapy. The study used a split-mouth design where two intrabony defects were randomly chosen to receive fisiograft (polylactic and PGA copolymer) with OFD (Group 1) on 15 sites and remaining 15 sites were chosen only for OFD alone (Group 2). Statistical Analysis: Wilcoxon's signed-rank test as an alternative to paired t-test and Mann–Whitney U-test as an alternative to unpaired t-test were used for statistical analysis. Results: There was a decrease in probing pocket depth of 3.93 ± 0.08 mm for PGA/PLA with OFD and 3.14 ± 0.41 mm for OFD alone with a mean gain of relative clinical attachment level of 3.81 ± 0.30 and 2.46 ± 0.03 for PGA/PLA with OFD and OFD alone, respectively. Gingival margin position was 0.667 ± 0.51 mm and 3.626 mm for the PGA/PLA with OFD and OFD alone. The mean amount of defect fill for PGA/PLA with OFD and OFD alone was 1.80 ± 0.86 mm and 1.20 ± 0.94 mm, with a mean change in the level of alveolar crest after 6 months being 0.267 ± 0.46 and − 0.86 ± 0.74 for the two groups, respectively. The mean difference in percentage of original defect resolved when compared between the test and control groups 6 months postoperatively was found to be 31.85% which was statistically significant (P = 0.001). Conclusion: In the present study, fisiograft (polylactic and PGA copolymer) with OFD group showed better results than where OFD alone was used in the treatment of periodontal intrabony defects in terms of both clinical as well as radiographic assessment. Although Fisiograft® has shown promising results on clinical and radiological evaluation in the present study, it would be inappropriate to draw definite conclusions regarding the nature of the defect fill.

Keywords: Open flap debridement, periodontal intrabony defects, polylactic and polyglycolic acid copolymer


How to cite this article:
Jangid MR, Rakhewar P S, Nayyar AS, Cholepatil AR. Comparative evaluation of fisiograft (polylactic and polyglycolic acid co-polymer) with open flap debridement (OFD) versus open flap debridement (OFD) alone in the treatment of periodontal intra-bony defects: A clinical and radiographic study. J Clin Sci 2017;14:42-8

How to cite this URL:
Jangid MR, Rakhewar P S, Nayyar AS, Cholepatil AR. Comparative evaluation of fisiograft (polylactic and polyglycolic acid co-polymer) with open flap debridement (OFD) versus open flap debridement (OFD) alone in the treatment of periodontal intra-bony defects: A clinical and radiographic study. J Clin Sci [serial online] 2017 [cited 2021 Apr 11];14:42-8. Available from: https://www.jcsjournal.org/text.asp?2017/14/1/42/199171


  Introduction Top


Periodontal disease is one of the most prevalent afflictions worldwide. The most serious consequence is the loss of the periodontal supporting structures, which includes the periodontal ligament, alveolar bone, and cementum [1] resulting in the early loss of teeth. Regeneration of the lost periodontium is one of the major goals of periodontal therapy. Conventional periodontal treatment, such as scaling and root planning, is highly effective at repairing disease-related defects and halting the progression of periodontitis. However, they do little to promote regeneration of the lost periodontium. On the other hand, periodontal surgery, in particular, regenerative periodontal surgical procedures, aims not only to eliminate pockets but also to regenerate a new attachment apparatus and reconstructs the periodontal unit within previously existing normal physiologic limits. Historically, autogenous bone grafts were the first bone replacement grafts to be reported for periodontal application and are till today considered as the gold standard for periodontal regeneration.[2] However, disadvantages associated with autogenous bone grafts (need for second surgical site to procure tissue and the frequent lack of intraoral donor sites to obtain sufficient quantities of donor bone for multiple or deep osseous defects) spurred the development of periodontal bone allograft. An inorganic synthetic material seemed to fulfill the criteria for an “ideal” graft material. Several alloplastic materials have also been used in an attempt to improve clinical conditions and to regenerate the bone in periodontal intrabony defects. The alloplastic graft materials are plaster of Paris, polymers, calcium carbonates, ceramics, resorbable tricalcium phosphates, resorbable hydroxyapatite (HA), nonresorbable dense HA, porous HA, and bioglass.[3],[4] A systematic review on the effect of grafting biomaterials and biologic agents in the treatment of deep intrabony defects showed that a clinical benefit may be obtained from various bone substitutes used as an adjunct to open flap debridement (OFD) procedure. Overall, the results indicated that the implantation of bone substitutes produced a more favorable clinical attachment level (CAL) gain, probing pocket depth (PPD) reduction, and increased defect fill when compared to OFD procedure done alone.[5] Biodegradable polymers, especially those belonging to the family of polylactic acid (PLA) and polyglycolic acid (PGA), are playing an increasingly important role in bone reconstructive procedures. Although extensively used in orthopedics from more than a decade, PLA/PGA biomaterials have been scarcely used in craniomaxillofacial applications. In dentistry, surgical sutures and absorbable membranes in PGA and/or PLA acids have been available for use in guided tissue regeneration procedures.[6],[7] However, only in recent years, absorbable synthetic biopolymers have been used as bone fillers in periodontology, proving effective stimulants to bone regeneration in some cases.[8],[9] Implantation of PLA-derived devices was studied to prevent alveolar osteitis or dry socket in extraction sites [10],[11] and in the treatment of periodontal osseous defects with access flap alone, PLA implant, and decalcified freeze-dried bone allograft.[12] Recently, a new copolymer (Fisiograft ®, Ghimas s.r.l, Casalecchio di, Italy) of 50% DL-lactic acid and 50% glycolic acid (50 PLA: 50 PGA) mixed with dextran 125 as excipient has been marketed in different formulations, such as sponge, gel, and powder. Being synthetic, it is absolutely risk-free from cross-contamination due to pathological agents such as bacterial subacute endocarditis, hepatitis, and HIV. It is biocompatible and well tolerated as it is reabsorbed and degraded in Krebs cycle. It can be easily molded, shaped, and functions as an absorbable space maintainer. It has lower molecular weight which permits a more rapid biological degradation, completely absorbed within 4-6 months. Fisiograft ® has osteoconductive properties because it is penetrated by and totally substituted by trabecular bone.[13] The aim of this study was to evaluate the clinical outcome of reconstructive surgery in human deep intrabony defects with the use of fisiograft (polylactic and PGA copolymer) with OFD versus OFD alone in the treatment of periodontal intrabony defects.


  Materials and Methods Top


A clinical trial was carried out on 15 patients (thirty sites). The study uses a split-mouth design where two intrabony defects on the collateral sites were selected randomly and were assigned as the test and control site.

Test site (a): 15 sites were treated with the use of fisiograft (polylactic and PGA copolymer) [Figure 1] with OFD.
Figure 1: Fisiograft (sponge form)

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Control site (b): 15 sites were treated with OFD alone. All participants, following an initial examination and treatment planning appointment, were given detailed instructions in plaque control measures and were, then, subjected to full mouth scaling and root planning. At reevaluation, the proposed nature of the study was explained to the patient provided that the tissue response was satisfactory. A customized acrylic stent was fabricated for each patient.[14] The stent was grooved in an occluso-apical direction so that the probe could be returned to the same position for successive measurements and the clinical measurements could be made from a reproducible point at the apical end of the stent, which served as a fixed reference point.

Following clinical parameters were recorded at baseline (BL), 3 months, and 6 months postsurgery:

  1. Plaque index (PI) (Turesky-Gilmore-Glickman modification of Quigley-Hein PI, 1970)[15]
  2. Sulcus bleeding index (SBI) (Muhlemann and Mazor, 1958)[16]
  3. PPD measured from the crest of the gingival margin to the base of the pocket [Figure 2]
  4. CAL measured from cementoenamel junction (CEJ) to the base of pocket
  5. Gingival margin position (GMP) measured from the fixed reference point to the gingival margin [Figure 3].


Surgical procedure

Following local anesthesia, an intracrevicular incision was made [Figure 4] and a full thickness mucoperiosteal flap reflected attempting to retain all soft tissue. Following flap reflection, all accretions were removed from the root surfaces and the defects were debrided and saline irrigation was done [Figure 5]. The test sites (a) were treated in the same manner, however, following debridement of the root surfaces and bone defect, the Fisiograft ® graft was utilized to fill the defects to the most coronal level of the osseous walls and care was taken not to overfill the defect [Figure 6]. The control (b) as well as the test (a) sites were, then, sutured with interrupted sutures using 4-0 black silk sutures [Figure 7] and were supported with periodontal dressing (Coe-Pak) [Figure 8]. Patients were, then, periodically monitored at one, 3, and 6 months intervals after the surgical procedure. At each of the recall visits, oral hygiene was assessed and oral hygiene instructions were reinforced.
Figure 2: Fixed reference point to base of the pocket with customized acrylic stent fabricated for each patient being seen

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Figure 3: Fixed reference point to the gingival margin

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Figure 4: Incision being given

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Figure 5: With full thickness mucoperiosteal flap reflected, the accretions were removed from the root surface attempting to retain all soft tissue and the defect was debrided followed with saline irrigations

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Figure 6: Placement of Fisiograft (sponge form)

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Figure 7: Sutures placed

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Figure 8: Periodontal dressing (Coe-Pak) placed

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Postsurgical procedure

Following the surgical procedure, the patients were asked to refrain from tooth brushing, flossing, and interdental cleaning techniques in the treated areas for 2 weeks after surgery. After 1 week, dressing, sutures, and any plaque present in the area were removed. Recall appointments were, then, made at 14 days and 30 days for additional follow-ups and plaque control and then, for every 3 months up to a period of 6 months. PI, SBI, PPD, CAL, and change in GMP were recorded at 3 and 6 months intervals. Additional radiographs using film holders were taken at 6 months interval.

Standardized radiographs of the test (a) and control (b) sites were taken using a paralleling technique with a film holder. This was taken to measure the bone fill. Intraoral periapical (IOPA) radiographs of each site were digitized using a X-digi-USB IOPA X-ray digitizer (Jolly computers, Surat). The distance between the two points of each line was measured using the superimposed square gridlines pre- and post-operatively [Figure 9]a and [Figure 9]b. The CEJ, the base of the defect (BD), and the alveolar crest (AC) were located on the image. Using the connector line tool, two lines were drawn from CEJ to BD and also from CEJ to AC, respectively [Figure 10]a and [Figure 10]b. Subtracting the two measurements, the depth of the osseous defect was obtained.
Figure 9: (a and b) For measurements, connector line tool was used. The distance between the two points of each line was measured using the superimposed square gridlines pre- and post-operatively

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Figure 10: (a and b) The cementoenamel junction, the base of the defect, and the alveolar crest were located on the image. Using the connector line tool, two lines were drawn from cementoenamel junction to base of the defect and also from cementoenamel junction to alveolar crest, respectively. Subtracting the two measurements, the depth of the osseous defect was obtained

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Calculations made

The following calculations were made:

  1. BL depth of the defect = BL CEJ to BD − BL CEJ to the AC
  2. Postsurgical depth of the defect = Postsurgical BL CEJ to BD − BL CEJ to the AC.
  3. Amount of defect fill (mm) = Initial depth of the defect − postsurgical depth of the defect
  4. Change in AC level = AC level at BL − AC level postsurgically.
  5. % of the original defect resolved = % of defect fill − % of change in the level of AC.


Statistical analysis

Wilcoxon's signed-rank test as an alternative to paired t-test and Mann–Whitney U-test as an alternative to unpaired t-test were used for statistical analysis.

Wilcoxon's signed-rank test (alternative to paired t-test): Ranks were assigned to differences (from BL) without considering the signs. Original signs were retained to ranks. Sum of + ve and − ve ranks were found.

Least of the two sums was, then, compared with the table values for significance.

Mann–Whitney U-test (alternative to unpaired t-test): Ranks were assigned to the combined values of the two groups and then, ranks were separated to corresponding groups. Sum of the ranks was found (i.e., R1 and R2).





Least of U1 ∞ U2 is compared with table values for significance.


  Results Top


All 15 patients completed the study. The healing phase progressed uneventfully. No signs of inflammation, infection, and/or allergy were noted. The data obtained were compiled and subjected to statistical analysis. For all the parameters, the subject mean was the basis of the statistical analysis, not the sites alone. The data from the investigation are presented in [Table 1],[Table 2],[Table 3],[Table 4],[Table 5],[Table 6]. There was no change in the mean PI score [Table 1] and the mean SBI score [Table 2] when compared between the test and control groups at BL, 3 months, and 6 months postoperatively and the results were not found to be statistically significant. The intragroup comparison showed a reduction in the mean PI score and the mean SBI score at test (a) and control (b) sites from BL to 6 months postoperatively which was statistically significant in both the groups.
Table 1: Comparison of the mean plaque index score between the test and control groups at baseline, 3 months, and 6 months intervals postoperatively

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Table 2: Comparison of the mean sulcus bleeding index score between the test and control groups at baseline, 3 months, and 6 months intervals postoperatively

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Table 3: Comparison of the mean probing pocket depth score between the test and control groups at baseline, 3 months, and 6 months intervals postoperatively

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Table 4: Comparison of the mean clinical attachment level score between the test and control groups at baseline, 3 months, and 6 months intervals postoperatively

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Table 5: Comparison of the mean gingival margin position score between the test and control groups at baseline, 3 months, and 6 months intervals postoperatively

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Table 6: Comparison of the “osseous changes” between the test and control groups at baseline, 3 months, and 6 months intervals postoperatively

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Soft tissue changes

There was a decrease in PPD of 3.93 ± 0.08 mm for PGA/PLA with OFD and 3.14 ± 0.41 mm for OFD alone [Table 3] with a mean gain of relative CAL of 3.81 ± 0.30 and 2.46 ± 0.03 for PGA/PLA with OFD and OFD alone [Table 4], respectively. GMP was 0.667 ± 0.51 mm and 3.626 mm for the PGA/PLA with OFD and OFD alone [Table 5].

Osseous changes

The mean amount of defect fill for PGA/PLA with OFD and OFD alone was 1.80 ± 0.86 mm and 1.20 ± 0.94 mm, respectively. The mean percentage of defect fill was 46.55 ± 20.15 and 33.93 ± 24.75 for the two groups, respectively [Table 6]. The mean change in the level of AC after 6 months was 0.267 ± 0.46 and − 0.86 ± 0.74 for the two groups. The mean percentage of change in AC level after 6 months was 6.113 ± 10.67 and 23.78 ± 20.52 for the two groups, respectively [Table 6]. The mean percentage of original defect resolved after 6 months postoperatively was 42.07 ± 18.81 and 10.22 ± 27.2 for the two groups, respectively [Table 6]. The mean difference in percentage of original defect resolved when compared between the test and control groups 6 months postoperatively was found to be 31.85% which was statistically significant (P = 0.001) [Table 6].


  Discussion Top


The primary goal of periodontal treatment is the maintenance of the natural dentition in health and comfortable function.[17] When periodontal disease has caused a loss of the attachment apparatus, optimal care seeks to regenerate the periodontium to its predisease state. Loss of alveolar bone is one of the characteristic signs of destructive periodontal disease and is generally considered to represent the anatomical sequel to the apical spread of periodontitis.[18] To be considered a regenerative modality, a material or technique must histologically demonstrate that bone, cementum, and a functional periodontal ligament can be formed on a previously diseased root surface. Bone grafts and their synthetic substitutes have been used in an attempt to gain this therapeutic endpoint.[19] This study compared the soft tissue and hard tissue changes with the use of fisiograft (polylactic and PGA copolymer) with OFD versus OFD alone in the treatment of periodontal intrabony defects. A comparison of clinical parameters of PI, SBI, soft tissue parameters (PPD, CAL, and change in GMP) at BL, 3 months, and 6 months and hard tissue parameters at BL and 6 months were made. In this study, it is observed that the soft tissue changes such as PPD reduction, CAL gain, and GMP were seen maximum and statistically significant in the first 3 months and the changes seen in subsequent period, i.e., 3–6 months period were minimal in both grafted and nongrafted sites. In relation to the hard tissue changes, significant results were seen with respect to changes in AC and percentage of original defect resolved, but no significant changes were seen with respect to the amount of defect fill on comparison between test and control sites at 6 months postsurgery. However, radiographically, the grafted sites showed better and more positive results than debridement sites in relation to all the parameters. In grafted sites, the angular defects remained visible but diminished in size and increased in radio density, which was seen as healing progressed, not appreciated at OFD sites. Hence, Fisiograft ® polymer appeared to be a beneficial graft material for the repair of periodontal osseous defects. Measuring the success in osseous grafting requires an analysis of parameters to be used in comparative studies. Although the ultimate test for regeneration is histologic assessment, this measurement is often prevented in human trials due to ethical considerations. Human histological studies have found little or no new bone growth with OFD alone [20] and new bone growth was evident when fisiograft was used as a filler for bone defects in humans.[21]


  Conclusion Top


In the present study, fisiograft (polylactic and PGA copolymer) with OFD group showed better results than where OFD alone was used in the treatment of periodontal intrabony defects in terms of both clinical as well as radiographic assessment. Although Fisiograft ® has shown promising results on clinical and radiological evaluation in the present study, it would be inappropriate to draw definite conclusions regarding the nature of the defect fill.

Limitations of the study

Fisiograft ® showed promising results on clinical and radiological evaluation in the present study although it would be inappropriate to draw definite conclusions regarding the nature of the defect fill which remains a major limitation of the current study that should be evaluated in future studies in this area of research.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

 
  References Top

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Trombelli L, Heitz-Mayfield LJ, Needleman I, Moles D, Scabbia A. A systematic review of graft materials and biological agents for periodontal intraosseous defects. J Clin Periodontol 2002;29 Suppl 3:117-35.  Back to cited text no. 5
    
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Robert P, Mauduit J, Frank RM, Vert M. Biocompatibility and resorbability of a polylactic acid membrane for periodontal guided tissue regeneration. Biomaterials 1993;14:353-8.  Back to cited text no. 6
    
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Robert PM, Frank RM. Periodontal guided tissue regeneration with a new resorbable polylactic acid membrane. J Periodontol 1994;65:414-22.  Back to cited text no. 7
    
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Lundgren D, Nyman S, Mathisen T, Isaksson S, Klinge B. Guided bone regeneration of cranial defects, using biodegradable barriers: An experimental pilot study in the rabbit. J Craniomaxillofac Surg 1992;20:257-60.  Back to cited text no. 8
    
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Winet H, Hollinger JO. Incorporation of polylactide-polyglycolide in a cortical defect: Neoosteogenesis in a bone chamber. J Biomed Mater Res 1993;27:667-76.  Back to cited text no. 9
    
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Olson RA, Roberts DL, Osbon DB. A comparative study of polylactic acid, Gelfoam, and surgicel in healing extraction sites. Oral Surg Oral Med Oral Pathol 1982;53:441-9.  Back to cited text no. 10
    
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Brekke JH, Olson RA, Scully JR, Osbon DB. Influence of polylactic acid mesh on the incidence of localized osteitis. Oral Surg Oral Med Oral Pathol 1983;56:240-5.  Back to cited text no. 11
    
12.
Meadows CL, Gher ME, Quintero G, Lafferty TA. A comparison of polylactic acid granules and decalcified freeze-dried bone allograft in human periodontal osseous defects. J Periodontol 1993;64:103-9.  Back to cited text no. 12
    
13.
Minenna L, Herrero F, Sanz M, Trombelli L. Adjunctive effect of a polylactide/polyglycolide copolymer in the treatment of deep periodontal intra-osseous defects: A randomized clinical trial. J Clin Periodontol 2005;32:456-61.  Back to cited text no. 13
    
14.
Clark DC, Chin Quee T, Bergeron MJ, Chan EC, Lautar-Lemay C, de Gruchy K. Reliability of attachment level measurements using the cementoenamel junction and a plastic stent. J Periodontol 1987;58:115-8.  Back to cited text no. 14
    
15.
Turesky S, Gilmore ND, Glickman I. Reduced plaque formation by the chloromethyl analogue of Vitamin C. J Periodontol 1970;41:41-3.  Back to cited text no. 15
    
16.
Mühlemann HR, Son S. Gingival sulcus bleeding – A leading symptom in initial gingivitis. Helv Odontol Acta 1971;15:107-13.  Back to cited text no. 16
    
17.
Zander HA, Polson AM, Heijl LC. Goals of periodontal therapy. J Periodontol 1976;47:261-6.  Back to cited text no. 17
    
18.
Papapanou PN, Tonetti MS. Diagnosis and epidemiology of periodontal osseous lesions. Periodontol 2000 2000;22:8-21.  Back to cited text no. 18
    
19.
Rosen PS, Reynolds MA, Bowers GM. The treatment of intrabony defects with bone grafts. Periodontol 2000 2000;22:88-103.  Back to cited text no. 19
    
20.
Stahl SS, Froum SJ, Tarnow D. Human clinical and histologic responses to the placement of HTR polymer particles in 11 intrabony lesions. J Periodontol 1990;61:269-74.  Back to cited text no. 20
    
21.
Zaffe D, Leghissa GC, Pradelli J, Botticelli AR. Histological study on sinus lift grafting by Fisiograft and Bio-Oss. J Mater Sci Mater Med 2005;16:789-93.  Back to cited text no. 21
    


    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9], [Figure 10]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]



 

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