Expression of extracellular matrix macromolecules around demineralized freeze-dried bone allografts

Role of adjunct use of omega 3 fatty acids in periodontal therapy of periodontitis. A systematic review and meta-analysis

BACKGROUND

Host modulation therapy has emerged as a new concept for the treatment of periodontal disease. Recently, a lot of research is being done in product containing docosahexaenoic acid (DHA) and eicosapentanoic acid (EPA). Omega-3 PUFA have therapeutic, anti-inflammatory and protective properties. This systematic review analysed the adjunctive use of omega-3 fatty acids in periodontal therapy of periodontitis patients.

METHODS

PICO question (patient, intervention, comparison, and outcome) was formed. Keywords were generated and were fed in databases. The databases were Pubmed, Cochrane library and LIVIVO. Studies selected are Randomized clinical trial, clinical studies, and longitudinal studies. Meta -analysis were performed for Pocket depth (PD), Clinical attachment level (CAL), Gingival index (GI) and Plaque Index (PI). Risk of bias was also assessed.

RESULTS

On analysis of all the 8 studies at 3 months showed significant effect of omega -3 fatty acid on clinical attachment level (CAL), Pocket depth (PD). There was significant effect of omega-3 fatty acids in 4 studies at 6 months.

CONCLUSION

Within the limitation of the review, omega- 3 polyunsaturated fatty acids seems to have a positive effect on periodontal healing following periodontal therapy. Chronic periodontitis patient should be counselled to incorporate omega -3 fatty acid in their diet along with standard periodontal therapy.

Tibial tunnel enlargement and joint instability after anterior cruciate ligament reconstruction. A prospective comparison between autograft and allograft

PURPOSE

To investigate tibial tunnel widening and knee instability after ACL reconstruction with hamstring autograft or irradiated soft tissue allograft.

METHODS

Eight-two patients were divided into two groups: autograft group and allograft group. Radiographic and clinical evaluations were performed.

RESULTS

Seventy patients were followed up with median of 36.3 months (range 36-38 months). Tibial tunnel widening was at or greater than 30% for nine patients in the autograft group and 15 patients in the allograft group (P = 0.0417). The average percentage of tibial tunnel widening was 26.7 ± 4.0 % and 29.7 ± 5.3 % in autograft and allograft groups, respectively (P = 0.0090). Knee range of motion was not affected by the reconstruction operation or different grafts. Thigh atrophy improved significantly within 24 months after ACL reconstructions in both groups. ACL reconstruction with the allograft leaded to less knee stability than that with the autograft from one year after operation (P = 0.0023). There was no significant difference between two groups with respect to Lysholm score (P = 0.1925) and Tegner score (P =0 .0918) at the final follow-up.

CONCLUSION

The allograft group reported significantly more tibial tunnel widening and knee instability compared with the autograft group.

Crevicular fluid levels of interleukin-8, interleukin-17 and soluble intercellular adhesion molecule-1 after regenerative periodontal therapy

Objective:

The aim of this study is to evaluate the influence of regenerative periodontal therapy on clinical parameters and interleukin-8 (IL-8), IL-17 and soluble intercellular adhesion molecule-1 (sICAM-1) levels in gingival crevicular fluid (GCF) of subjects with chronic periodontitis (CP).

Materials and Methods:

Fifteen patients received demineralized freeze-dried bone allograft (DFDBA) surgically to the site of infrabony defect. Clinical periodontal indices were recorded, and GCF samples were collected at baseline and at the 6^th and the 9^th month after the surgery.

Results:

Except plaque index, all clinical parameters improved following surgery (P < 0.05). The volume of GCF diminished from baseline to follow-up periods (P < 0.05). However, no effect was observed on the total amount of IL-8, IL-17 and sICAM-1 in GCF.

Conclusion:

DFDBA improved clinical outcome in CP subjects and was effective on decreasing the volume of GCF, but no effect was determined on IL-8, IL-17 and sICAM-1. Findings did not indicate a direct relationship between biochemical parameters and periodontal healing after demineralized freeze-dried bone grafting.

Evaluation of bioactive glass and demineralized freeze dried bone allograft in the treatment of periodontal intraosseous defects: A comparative clinico-radiographic study

AIM

The purpose of this study was to evaluate the efficacy of demineralized freeze dried bone allograft (DFDBA) and bioactive glass by clinically and radiographically in periodontal intrabony defects for a period of 12 months.

MATERIALS AND METHODS

Ten systemically healthy patients diagnosed with chronic periodontitis, with radiographic evidence of at least a pair of contralateral vertical osseous defects were included in this study. Defect on one-side is treated with DFDBA and the other side with bioactive glass. Clinical and radiographic measurements were made at baseline 6 month and 12 month after the surgery.

RESULTS

Compared to baseline, the 12 month results indicated that both treatment modalities resulted in significant changes in all clinical parameters (gingival index, probing depth, clinical attachment level (CAL) and radiographic parameters (bone fill); P < 0.001*). However, sites treated with DFDBA exhibited statistically significantly more changes compared to the bioactive glass in probing depth reduction (2.5 ± 0.1 mm vs. 1.8 ± 0.1 mm) CAL gain 2.4 ± 0.1 mm versus 1.7 ± 0.2 mm; (P < 0.001*). At 12 months, sites treated with bioactive glass exhibited 56.99% bone fill and 64.76% bone fill for DFDBA sites, which is statistically significant (P < 0.05*).

CONCLUSION

After 12 months, there was a significant difference between the two materials with sites grafted with DFDBA showing better reduction in probing pocket depth, gain in CAL and a greater percentage of bone fill when compared to that of bioactive glass.

ACL graft healing and biologics

Operative reconstruction of a torn anterior cruciate ligament (ACL) has become the most broadly accepted treatment. An important, but underreported, outcome of ACL reconstruction is graft failure, which poses a challenge for the orthopedic surgeon. An understanding of the tendon-bone healing and the intra-articular ligamentization process is crucial for orthopedic surgeons to make appropriate graft choices and to be able to initiate optimal rehabilitation protocols after surgical ACL reconstruction. This article focuses on the current understanding of the tendon-to-bone healing process for both autografts and allografts and discusses strategies to biologically augment healing.

Allografts in Anterior Cruciate Ligament Reconstruction

Usual allograft sources for anterior cruciate ligament (ACL) reconstruction are patellar ligament, Achilles tendon, tibialis anterior, and posterior. The advantages of the use of allograft include reduced donor-site morbidity, shorter operative time, smaller incisions, and no size restrictions. The disadvantages include increased cost, slower graft embodiment, and the risk of viral or bacterial infection, which may occur either by transmission from an infected donor or by contamination by the healthcare provider. Careful donor selection, aseptic graft procurement and processing, and tissue sterilization, by irradiation or proprietary chemical processing, are the three major steps of the graft preparation procedure. Successful allograft implantation depends on sterility, reduction of antigenicity, and preservation of the biomechanical properties of the graft. To date, reports on the clinical and functional outcomes of allograft compared to autograft ACL reconstruction are controversial. Overall, graft choice depends on surgeon and patient preference, since no graft can perfectly match the properties of the native ACL.

The efficacy of host response modulation therapy (omega-3 plus low-dose aspirin) as an adjunctive treatment of chronic periodontitis (clinical and biochemical study)

BACKGROUND AND OBJECTIVE

Regeneration of lost periodontal tissues is considered to be one of the most challenging aspects of periodontal therapy. Our current understanding of the role of the host immuno-inflammatory response in periodontal diseases forms the basis of new therapeutic approaches. The aim of this study was to evaluate the efficacy of systemic administration of omega-3 polyunsaturated fatty acids plus low-dose aspirin as an adjunctive treatment to regenerative therapy of furcation defects.

MATERIAL AND METHODS

Forty patients displaying at least a single grade II furcation defect were enrolled in the study. They were randomly allocated into two groups: an experimental group receiving decalcified freeze-dried bone allograft (DFDBA) + omega-3 polyunsaturated fatty acids combined with low-dose aspirin; and a control group receiving DFDBA + placebo. Clinical parameters were monitored at baseline, and at 3 and 6 mo following therapy, and included plaque index, gingival index, gingival bleeding index, probing pocket depth and clinical attachment level. The biochemical markers assessed in gingival crevicular fluid samples were interleukin-1β and interleukin-10.

RESULTS

The experimental intervention resulted in a greater mean probing pocket depth reduction (P < 0.001) and gain in clinical attachment (P < 0.05) compared with the control at 6 mo. Furthermore, the experimental protocol was able to achieve a significant modulatory effect on the levels of interleukin-1β and interleukin-10 compared with control therapy.

CONCLUSION

The findings suggest that the combination therapy demonstrated successful reduction of gingival inflammation, reduction of pocket depth and attachment level gain, accompanied by a trend for modulation of the cytokines profile in gingival crevicular fluid.

Biology of autograft and allograft healing in anterior cruciate ligament reconstruction

The graft-bone attachment site is the weak link in anterior cruciate ligament (ACL) reconstruction surgery because healing is slow and often incomplete. Each of the many graft options for ACL reconstruction surgery has different healing characteristics and potential. Autografts that allow bone-to-bone healing offer the best healing potential. An understanding of the biology of graft healing should give the surgeon context in graft selection and rehabilitation for ACL reconstruction.

Quantitative and sensitive in vitro assay for osteoinductive activity of demineralized bone matrix

A sensitive, rapid, reliable and quantitative method to check the bone forming potential of demineralized bone matrix (DBM) has been developed. The osteoinductivity of the bone morphogenetic proteins (BMPs), present in DBM, can be measured in vitro using a pluripotent myoblast C2C12 cell line. Alkaline phosphatase activity induced by co-incubation of DBM with C2C12 cells was dose-responsive and corresponds to the amount of active BMPs in DBM. Bone forming potential was simultaneously tested in vivo by implanting DBM intra-muscularly in nude rats. ALP activity induced in C2C12 cells, correlated with bone formation in vivo (r=0.88), determined by alkaline phosphatase activity, mineralization density and histomorphology of the DBM explants. Results from DBM batches, originating from five established Bone Banks, showed good consistency between in vitro and in vivo assays. However, DBM activity varied widely from bank to bank as well as from batch to batch within the same bank.

Identification of Bone Morphogenetic Proteins 2 and 4 in Commercial Demineralized Freeze-dried Bone Allograft Preparations: Pilot Study

BACKGROUND

Demineralized freeze-dried bone allografts (DFDBAs) have been proposed as a useful adjunct in periodontal therapy to induce periodontal regeneration through the induction of new bone formation. The presence of bone morphogenetic proteins (BMPs) within the demineralized matrix has been proposed as a possible mechanism through which DFDBA may exert its biologic effect. However, in recent years, the predictability of results using DFDBA has been variable and has led to its use being questioned. One reason for the variability in tissue response may be attributed to differences in the processing of DFDBA, which may lead to loss of activity of any bioactive substances within the DFDBA matrix. Therefore, the purpose of this investigation was to determine whether there are detectable levels of bone morphogenetic proteins in commercial DFDBA preparations.

METHODS

A single preparation of DFDBA was obtained from three commercial sources. Each preparation was studied in triplicate. Proteins within the DFDBA samples were first extracted with 4M guanidinium HCI for seven days at 40 degrees celsius and the residue was further extracted with 4M guanidinium HCL/EDTA for seven days at 40 degrees celsius. Two anti-human BMP-2 and -4 antibodies were used for the detection of the presence of BMP's in the extracts.

RESULTS

Neither BMP-2 nor BMP-4 was detected in any of the extracts. When recombinant human BMP-2 and -4 were added throughout the extraction process of DFDBA extraction, not only were intact proteins detected but smaller molecular weight fragments were also noted in the extract.

CONCLUSIONS

These results indicate that all of the DFDBA samples tested had no detectable amounts of BMP-2 and -4. In addition, an unknown substance present in the DFDBA may be responsible for degradation of whatever BMPs might be present.

Clinical evaluation of the treatment of class II furcation involvements with bioabsorbable barriers alone or associated with demineralized freeze-dried bone allografts

BACKGROUND

Class II furcation lesions are a challenging scenario for periodontal therapy and a serious threat for tooth prognosis. Guided tissue regeneration represents a viable treatment option, but some aspects remain to be clarified as to the efficacy of bone substitutes used in GTR procedures. The clinical efficacy of demineralized freeze-dried bone allografts (DFDBA) for regenerative procedures is presently under scrutiny.

METHODS

This study evaluated the adjunctive clinical effects of DFDBA associated with a bioabsorbable (polylactic acid) barrier membrane in the regenerative treatment of human Class II furcation lesions as compared to the same type of barrier alone. Twelve patients with bilateral Class II furcation defects on lower first molars participated in the study. In each patient, one tooth was randomly assigned to treatment consisting of open surgical debridement followed by the placement of DFDBA (GTR+DFDBA, or test group) and a bioabsorbable barrier, while the contralateral side received the same flap surgery followed by use of the bioabsorbable membrane alone (GTR, or control group). The clinical efficacy of the 2 treatment modalities was evaluated at 6 and 12 months postoperatively. Measurements included vertical probing depth (VPD), horizontal probing depth (HPD), clinical attachment level (CAL), amount of gingival recession (GR), and change in class of clinically detectable furcation involvement (FC).

RESULTS

Both treatments yielded significant improvements for all clinical parameters between baseline and 6 and 12 months (P<0.05). The comparison between test and control groups revealed significantly greater reduction in HPD (P=0.01) and higher values of GR (P=0.008) for the test group. The mean gain in HPD for test sites was 2.3 mm, while it amounted to 1.7 mm for controls. A significantly greater proportion of test sites could be classified postoperatively as Class I defects compared to controls (91% versus 50%, respectively).

CONCLUSIONS

The results of this study indicate that significant improvements from baseline occurred in VPD, HPD, CAL, and clinically detectable furcation involvement after the treatment of Class II furcation lesions with a bioabsorbable membrane with or without the adjunctive use of DFDBA. In addition, the placement of DFDBA in the furcation defect under the bioabsorbable membrane resulted in a greater mean reduction of horizontal probing depth when compared to the regenerative therapy alone.

An assessment of the osteoinductive potential of commercial demineralized freeze-dried bone in the murine thigh muscle implantation model

Early studies have demonstrated that implantation of laboratory preparations of demineralized freeze dried bone (DFDB) into the thigh muscle of mice induces ectopic osteoinduction. However, with the development of commercial preparations of DFDB for clinical use, concerns have been raised as to the osteoinductive properties of such preparations. The aim of this study was to investigate the osteoinductive potential of some commercial preparations of DFDB compared to a newly developed product which incorporates DFDB into a collagen sponge. Commercial preparations of DFDB or the DFDB/collagen sponge were inserted into the thigh muscles of 60 adult Swiss CD-1 mice. At the completion of each experimental period (7, 14, 30, 90 and 180 days), the animals were sacrificed, and the hindquarters of the mice were radiographed. The area where each graft had been placed was then excised, processed for light microscopy, and stained with hematoxylin and eosin or von Kossa's stain. Histological analysis of the DFDB/collagen sponges demonstrated significant remineralization which increased with time. Remineralization of the DFDB/collagen sponges was verified by radiographs which showed a significant increase in radiopacity over time. There was no radiographic evidence of mineralized tissue formation or remineralization in any of the commercial DFDB samples studied. At all time points studied, histological analyses failed to show evidence of bone formation for any of the preparations. The results suggest that commercially available DFDB is not osteoinductive in the murine model and question the use of such materials in clinical periodontics. The results found for the DFDB/collagen sponge indicate a different mechanism of activity from DFDB as evidenced by its rapid remineralization. The role this remineralization process has in osteoinduction is unknown and requires further study.

Histologic findings after implantation and evaluation of different grafting materials and titanium micro screws into extraction sockets: case reports

The purpose of this study was to compare extraction socket healing in 8 patients after implantation with either xenogenic bovine bone (n=5 sites), demineralized freeze-dried bone (DFDBA) (n=3 sites), autologous bone (n=3 sites), or human bone morphogenetic proteins in an osteocalcein/osteonectin carrier (hBMP/NCP) (n=2 sites). Three of the patients received 6 commercially pure micro screws which were fixed into extraction sockets, after which the sockets were implanted with either bovine bone (n=3 sites), DFDBA (n=2 sites) or intraoral autologous bone (n=1 site). Biopsies of the extraction sockets were taken from 3 to 6 months after treatment (average, 4.6 months). For comparison of healing between the implanted materials, histologic evaluation and bone scores were determined. Bone scores of 0 indicated an absence of new bone, with dead implanted bone particles entrapped within connective tissue, while a score of 3 indicated the entire field consisted of vital bone. Biopsies from bovine bone sockets revealed dead implanted particles surrounded by connective tissue. Isolated sections showed host bone in contact with the bovine bone particles. Bone scores ranged from 0 to 3. Biopsies from DFDBA-implanted sites revealed dead particles entrapped with dense connective tissue. The bone scores ranged from 0 to 1. Biopsies from sites implanted with hBMP/NCP revealed a combination of woven and lamellar bone with bone scores of 3. Five of the 6 micro screws were processed and evaluated. One screw was mobile at the time of removal and was not evaluated. Bone scores were used to compare new bone formation adjacent to the micro screws. Bone scores ranged from 0 to 2. A score of 0 indicated non-vital implant material in contact with host bone and connective tissue in contact with implant; 2 indicated vital bone in contact with the majority of the implant surface. Retrieved sockets with micro screws implanted with bovine bone (n=2) demonstrated a connective tissue interface between the screws and the surrounding tissues (bone score 0). The adjacent tissues showed dead bovine particles entrapped within fibrous tissue. Retrieved screws implanted with DFDBA (n=2) were surrounded by connective tissue, with dead bone particles enmeshed within fibrous tissue (bone score 0). The screw implanted with intra-oral autologous bone was primarily surrounded by vital bone with a connective tissue interface (bone score 1). Three implant threads were in contact with bone. The results of this study indicate that bovine bone, DFDBA, and intraoral autologous bone do not promote extraction socket healing. Sockets implanted with hBMP/NCP contained vital woven and lamellar bone. Xenogenic bovine bone and DFDBA did not contribute to bone to micro screw contacts and are not recommended for enhancement of vital bone to implant contacts. Intraoral autogenous bone also does not appear to significantly contribute to bone to implant contacts. Intraoral autologous bone, xenogenic bone, and DFDBA appear to interfere with normal extraction socket healing.