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Reaction of oral tissues to suture materials
Reaction of oral tissuesto suture materials Part
II
Gilbert E. Lilly, Lieutenant Colonel, DC, UXA,Ic James H. Armstrong, B.S., *+ John E. Salem, Major, DC, lrSA,“+” and James L. Cutcher, Lieutenant Colonel, DC, USA**” UNITED
STATES ARMY MEDICAL
PRESIDIO OF SAN FRANCISCO,
RESEARCH UNIT,
CALIF.
T
here is currently available to the clinician a wide variety of suture materials for the closure of oral wounds. Although these materials have been evaluated in animals and in human beings, such investigations have usually involved the closure of wounds other than those of the oral cavity.1-17 A previous investigation in this laboratory has indicated that, in dogs, the comparative reaction of oral tissues to suture materials placed through the intact mucosa is not the same as that reported for other anatomic sites.l* This investigation revealed that the monofilament suture materials evaluated (steel, nylon, gut, and chromic) resulted in a milder tissue response than the multifilament materials (polyester, twisted silk, cotton, braided silk, and linen). These findings suggested that the physical nature of the suture may be an important factor affecting the response o’f oral tissues to sutures placed through the oral mucosa.. The morphologic characteristics of the respective sutures may result in differences in their “wicking” action, which could result in the transmission of a variable number of bacteria to the depths of the wound. This variation in the number of bacteria may be responsible for observed differences in tissue response. In view of the possible effect of bacteria on tissue response and the fact that the previous investigation involved animals that were not receiving antibiotic therapy, t.he present study was undertaken to evaluate the effect of systemic antibiotics on the comparative response of oral tissues to sutures. In addition, an attempt was made to relate the presence of bacteria in tissue to the type of suture material used. *Chief, Oral and Maxil1ofacia.l Sciences Program. **Chief, Histopathology Laboratory, Oral and Maxillofacial “““Oral and Maxillofacial Sciences Program. ****Assistant Chief, Oral and Maxillofa&al Sciences Program.
592
Sciences Program.
Oral tissue reaction to suture materials
Volume 26 Number 4
593
MATERIALS AND METHODS Nine different commercially available suture materials were selected for this study (Table I). These were the same materials used in the previous investigation.18 All sutures were of the 4-O size and were prepa,ckaged in individual sterile packs. Sixteen adult mongrel dogs served as the experimental subjects. Each animal was given 500,006 units of procaine penicillin and 0.25 grams of streptomycin intramuscularly one hour before the start of the experimental procedure. This antibiotic therapy was repeated daily until the animal’s death. Each animal was given a general anesthetic, and interrupted sutures were placed through the intact buccal mucosa and lateral border of the tongue with a half-circle cutting needle. A separate sterile needle was used for each suture. Nine sutures (one of each type) were placed in the buccal mucosa, and a similar number and type were placed in the tongue of each animal. The anatomic location of the different suture materials varied from one animal to another. Fourteen of the animals were sa,crificed in groups of two at 1, 2, 3, 4, 6, 8, and 10 days postoperatively. At death, the tissues were recovered by block section and fixed in 10 per cent neutral buffered formalin. Block sections were grossed at a point perpendicular to the suture path at the greatest suture depth. After grossing, the sutures were carefully removed and the tissues were processed for histologic study. Multiple sections were cut at 5 microns and routinely stained with hematoxylin and eosin. All sections were examined microscopically without the examiner knowing the type of suture material used. The tissue reaction was arbitrarily classified as mild, moderate, or severe, depending upon its intensity, nature, and extent. Selected sections were stained after the method of Brown and Brenn (B and B) and examined for the presence of bacteria. Two animals were sacrificed at 4 and 6 days, respectively. Their tissues were processed as previously described, except that the sutures were not removed
Table I T&sue response Suture material
1
Mild
1 Mod&-ate
1
Severe ---I 1 ( 4%)
.-:I’ -’ specwnens .--. 26 17 26
Nylon (monofilament) 15 (57%) 10 (39%) Surgical gut (plain) 6 (35%) 10 (59%) Chromic (medium) 12 (46%) 9 (35%) Steel (mohofih&ment) 10 (37%) 12 (44%) Silk (black braided) 7 (25%) 16 (59%) Polyester Aber (green braided) 9 (32%) 12 (43%) Cotton (white twisted) ;; 3 (11%) 15 (55%) Dermal (black twisted silk) 26 2 ( 7%) 17 (65%) Linen (natural color) 24 1 ( 5%) 15 (62%) The figures under each type of tissue response indicate the number of specimens judged representative for each response to each material. Percentages are based on the total number of tissue specimens available for each suture material. Suture materials are listed in the order of their comparative mean tissue response, based on arbitrary values of 1, 2, s,ud 3 assigned to “mild,” “moderate,” and “severe” responses.
594
Lilly
et al.
O.S., O.M. & O.P. October, 1968
when the tissues were grossed, However, the steel sutures were rcmovrd prior to histologic processing. RESULTS
In most instances, four tissue specimens were availa.ble for each suture material for each sacrifice date. Occasionally, however, sutures were lost during the postoperative, phase, and gut sutures were not present in the B- and lo-day specimens. With the noted exception of gut (at 8 and 10 days), there was a minimum of three specimens available for microscopic study in e,achinstance. The results of the microscopic examination are summarized in Table I. In general, the inflammatory response was less exaggerated than that previously observed in animals not receiving systemic antibiotics.18 The reactions associated with the sutures placed in the buccal mucosa and tongue were comparable and, therefore, will not be described separately. The tissue responses during the first three postoperative sacrifice dates (1, 2, and 3 days) were less consistent for specific suture materials than those observed in later specimens. Reactions associated with l-day specimens consisted of hemorrhage, edema,,and a mild inflammatory infiltrate which was primarily neutrophilic. There was little variability among the different types of suture materials, and most reactions were classified as moderate (Fig. 1). Specimens examined 2 and 3 days after placement of sutures exhibited divergent reactions which were more consistent for each type of suture material. Mild reactions consisted of a localized inflammatory infiltrate of neutrophils, lymphocytes, and histiocytes. Early evidence of fibroblastic activity was observed (Fig. 2). Severe reactions contained a broader zone of inflammatory reaction, with a dense infiltrate of neutrophils and little evidence of fibroblastic proliferation (Fig. 3).
1. Moderate reaction associated with cotton suture edema, hemorrhage, and diffuse inflammatory x40.) ly neutrophi lit. (Magnification, Fig.
operatively.Note
in buccal mucc ,sa, 1 day postinfiltrate which is pr edomi nant-
Volume 26 Number 4
Oral tissue reactiolz to suture materials
595
Four to 6 days after placement of sutures, mild reactions were characterized by increased fibroblastic proliferation and a circumscribed inflammatory infiltrate of lymphocytes, neutrophils, and plasma cells (Fig. 4). An occasional foreign-body giant cell was observed. These did not appear to be specific for any type of suture material. In the severe reactions, there was no evidence of significant fibroblastic proliferation or foreign-body giant cells. The inflammatory infiltrate was dense, not circumscribed, and predominantly neutrophilic. Suture abscesses, however, were not observed (Fig. 5). Eight to 10 days after placement of sutures, mild reactions exhibited progressive fibrosis and contained a mild infiltrate of plasma cells and lymphocytes (Fig. 6). Foreign-body giant cells were observed in some cases. These were not specific for any type of suture materials. Severe reactions con-
Fig. a
Fig.
3
Fig. 9. Mild reaction associated with monofilament gut suture in buccal mucosa, 3 days postoperatively, showing early evidence of fibroblastic proliferation. Note mixed inflammatory infiltrate of neutrophils, plasma cells, and lymphocytes. (Magnification, x100.) Fig. 8. Severe tissue reaction in tongue associated with multifilament braided silk, 3 days postoperatively. Note dense infiltrate of neutrophils. (Magnification, x100.)
596
Lilly
et al.
4
Fig. 5
Fig. 4. Mild reaction in bucoal mucosa to monofilament steel suture, 4 days postoperatively. Tissues are infiltrated by lymphocytes and plasma cells. (Magnification, x100.) Fig. 5. Severe reaction in tongue associated with twisted silk (Dermal), 6 days postoperatively. Note dense infiltrate of neutrophils. Void at upper right-hand corner represents suture site. (Magnification, x200.)
tained a diffuse neutrophilic inflammatory infiltrate with microabscesses (Fig. 7). Approximately one half of the specimens associated with multifilament sutures contained microabscesses. Responses that were judged to be moderate were observed at all postoperative dates. These were considered to be intermediate between the mild and the severe reactions. A detailed description of these reactions is not considered necessary. None of the sections interpreted as showing moderate rea,ctions contained microabscesses. Small particles which appeared to represent bacteria were observed in almost all sections stained by the Brown and Brenn method prepared from specimens from which the sutures had been removed prior to processing. These bacteria were usually located in the void left by the removed suture and on the mucosal
Volume 26 Number 4
Oral tissue reaction. to suture materials
Fig.
597
6
Fig. 7
Pig. 6. Mild tissue reaction associated with monofilament nylon suture in tongue, 10 days postoperatively. Numerous fibroblasts are observed, and collagen formation is evident. Note sparse inflammatory infiltrate. (Magnification, x200.) Fig. 7. Severe tissue response associated with multifilament polyester suture in tongue, 8 days postoperatively. Note dense uncircumscribed inflammatory infiltrate, which is predominantly neutrophilic. Dense cellular areas adjacent to suture site were interpreted as microabscesses. (Magnification, x40.)
surface. They were seldom identified deep within the tissue. The number of bacteria present varied considerably from one specimen to another. Although no attempt was made to correlate the number of bacteria present with the type of suture, their numbers did appear to be roughly correlated with the degree of tissue response. Brown and Brenn staining revealed that sections prepared from specimens with sutures in place contained numerous small particles within the interstices of the multifilament sutures (Fig. 8). On the basis of their morphology and staining characteristics, these particles were interpreted as bacteria. Similar particles also were observed in association with monofilament sutures. These were fewer in number, however, and did not permeate the suture.
O.H., OX 84O.P. CMobtv, 1968
Fig. 8. Cross section of multifilament braided silk suture in buccal mucost+, 6 days postoperatively. Numerous small particles between silk filaments rrcrr interpreted as bacteria. (Brown and Brenn stain. Magnification, x900.)
DISCUSSION Although the tissue response to ea.ch suture material was variable, there was sufficient consistency to permit a categorization of the different suture materials. The monofila,ment materials were associated with less severe tissue responses than the multifilament materials. This finding is the same as that reported in a previous study in which the same suture materials were placed in dogs that were not receiving systemic antibiotic therapy.ls There was some minor variation from previous findings in the relative acceptability of the sutures within the monofilament and multifilament groups. Some of this varia,tion may have been due to trauma associated with suture placement, particularly in regard to the steel suture. Although systemic antibiotics appeared to reduce the tissue response to oral sutures, they did not appreciably alter the compa,rative response to the various suture materials. These findings indicate that the tissue reaction to the placement of oral sutures is different from that reported for other anatomic locations59 Gsg, I13I2 These results provide additional s~~pport to the thesis suggested by Katz and Evans7 that the physical nature of the suture is a major factor affecting tissue response. The particles interpreted as bacteria., observed between the filaments of the multifilament suture material in sections stained by the Brown and Brenn method, suggest that variation in bactesial transmission is responsible for this difference. This, coupled with the over-all reduction in the magnitude of the tissue response observed in these animals receiving antibiotics, as compared to previous work, further suggests that bacteria, play a role in determining the tissue reaction and that certain oral sutures do act as wicks. The ability of sutures to transmit bacteria has been demonstrated in vitro in this laboratory. These studies, however, have failed to demonstrate any selective differences between the various suture materials. This failure to
Volume 26 Number 4
Oral tissue reactiost to suture materials
demonstrate differences in bacterial transmission inadequacies in our laboratory model.
is considered
599
to be due to
SUMM.ARY The response of oral tissues to nine different suture materials was studied histologically in dogs that were receiving systemic antibiotic therapy. The monofilament suture materials-nylon, gut, steel, and chromic-were associated with less severe reactions than the multifilament materials-silk (braided), polyester fiber, cotton, Dermal (twisted silk), and linen. These findings indicate that the oral tissue response is related to the physical nature of the suture and that systemic antibiotics do not appreciably alter the comparative response to various suture materials. Brown and Brenn staining of tissue sections demonstrated particles within the interstices of multifilament suture materials, suggesting that variation in the transmission of bacteria may account for the difference in tissue response. REFERENCES
1. Bellas, J. E.: Influence of Sutures Upon Operative Wounds, Ann. Surg. 112: 112-121, 1940. 2. Britt! C!. I., Miller, E. M., Felder, M. E., and Sirak, H. D.: Comparative Reaction of Mersilene and Silk Sutures Implanted Within the Heart, Ann. Surg. 153: 52-62, 1961. 3. Corm, Julius, and Beal, J. M.: Evaluation of Multistrand Stainless Steel Wire Sutures, Am. J. Surg. 103: 593596, 1962. 4. Dettinger, G. B., and Bowers, W. F.: Tissue Response to Orlon and Dacron Sutures: A Comparison With Nylon, Cotton, and Silk, Surgery 42: 325-335, 1957. 5. Gaskin, E. R., and Chdders, M. D.: Increased Granuloma Formation From Absorbable Sutures, J. A. M. A. 185: 142-144, 1963. 6. Homes, E. L.: The Strength of Wounds Sutured With Catgut and Silk, Surg. Gynec. & Obst. 57: 309-317, 1935. Sutures : An Evaluation of Tissue 7. Katz,. A. B., and Evans, H. D. : Linear Polyethylene Reaction, Am. J. Surg. 103: 208-216, 1962. 8. Large, 0. P.: Comparison of Tissue tiactions From New Sutures, Am. J. Surg. 60: 414-423, 1943. 9. Deterling, R. A., Jr., Coleman, C. C., Jr., Kee, J., and Humphreys, C. H., II: An Experimental Evaluation of Catgut as a Vascular Suture Material and a Report on Its Clinical Use, J. Thorax. Surg. 23: 303-326, 1952. 10. Latimer, E. O., and Werr, J. A.: ClinicaI Experience With Dacron as a Nonabsorbable Suture Material, Surg. Gynec. & Obst. 112: 373-374, 1961. 11. Localio, 5. A. Casale, W., and Hinton, J. W.: Wound Healing-Experimental and Statistical Study. V. Bacteriology and Pathology in Relation to Suture Material, Surg. Gynec. & Obst. 77: 481-492, 1943. 12. Madsen, E. T.: An Experimental and Clinical Evaluation of Surgical Suture Materials. II, Surg. Gynec. & Obst. 97: 439-444, 1953. 13. Narat, J. K., Cangelosi, J. P., and Belmonte, J. V.: Evaluation of Dacron Suture Material for General Surgery, Surg. Forum 7: 176-178, 1957. 14. Postlethwait, R. W., Floyd, B. J., Dillon, M. L., and Stowe, D. G.: Tissue Reaction to Blood Vessel Sutures, Am. Surg. 28: 799-801, 1962. 15. Postlethwait, R. W., Schauble, J. F., Dillon, M. L., and Morgan, J.: Wound Healing. Il. An Evaluation of Surgical Suture Material, Surg. Gynec. & Obst. 108: 555-566, 1959. 16. Postlethwait, R. W., Schauble, J. F., Dillon, M. L., and Freeman, J. Wound Healing, Arch. Surg. 78: 948961, 1959. 17. Shumacker, H. B., and Mandelbaum, I.: Clinical Evaluation of Dacron Suture Material, Arch. Surg. 83: 647-649, 1961. 18. Lilly, G. E.: Reaction of Oral Tissues to Suture Materials, ORAL Suao., On,.& MED. & On&r, PATH. 26: 128-133, 1968.
II
Gilbert E. Lilly, Lieutenant Colonel, DC, UXA,Ic James H. Armstrong, B.S., *+ John E. Salem, Major, DC, lrSA,“+” and James L. Cutcher, Lieutenant Colonel, DC, USA**” UNITED
STATES ARMY MEDICAL
PRESIDIO OF SAN FRANCISCO,
RESEARCH UNIT,
CALIF.
T
here is currently available to the clinician a wide variety of suture materials for the closure of oral wounds. Although these materials have been evaluated in animals and in human beings, such investigations have usually involved the closure of wounds other than those of the oral cavity.1-17 A previous investigation in this laboratory has indicated that, in dogs, the comparative reaction of oral tissues to suture materials placed through the intact mucosa is not the same as that reported for other anatomic sites.l* This investigation revealed that the monofilament suture materials evaluated (steel, nylon, gut, and chromic) resulted in a milder tissue response than the multifilament materials (polyester, twisted silk, cotton, braided silk, and linen). These findings suggested that the physical nature of the suture may be an important factor affecting the response o’f oral tissues to sutures placed through the oral mucosa.. The morphologic characteristics of the respective sutures may result in differences in their “wicking” action, which could result in the transmission of a variable number of bacteria to the depths of the wound. This variation in the number of bacteria may be responsible for observed differences in tissue response. In view of the possible effect of bacteria on tissue response and the fact that the previous investigation involved animals that were not receiving antibiotic therapy, t.he present study was undertaken to evaluate the effect of systemic antibiotics on the comparative response of oral tissues to sutures. In addition, an attempt was made to relate the presence of bacteria in tissue to the type of suture material used. *Chief, Oral and Maxil1ofacia.l Sciences Program. **Chief, Histopathology Laboratory, Oral and Maxillofacial “““Oral and Maxillofacial Sciences Program. ****Assistant Chief, Oral and Maxillofa&al Sciences Program.
592
Sciences Program.
Oral tissue reaction to suture materials
Volume 26 Number 4
593
MATERIALS AND METHODS Nine different commercially available suture materials were selected for this study (Table I). These were the same materials used in the previous investigation.18 All sutures were of the 4-O size and were prepa,ckaged in individual sterile packs. Sixteen adult mongrel dogs served as the experimental subjects. Each animal was given 500,006 units of procaine penicillin and 0.25 grams of streptomycin intramuscularly one hour before the start of the experimental procedure. This antibiotic therapy was repeated daily until the animal’s death. Each animal was given a general anesthetic, and interrupted sutures were placed through the intact buccal mucosa and lateral border of the tongue with a half-circle cutting needle. A separate sterile needle was used for each suture. Nine sutures (one of each type) were placed in the buccal mucosa, and a similar number and type were placed in the tongue of each animal. The anatomic location of the different suture materials varied from one animal to another. Fourteen of the animals were sa,crificed in groups of two at 1, 2, 3, 4, 6, 8, and 10 days postoperatively. At death, the tissues were recovered by block section and fixed in 10 per cent neutral buffered formalin. Block sections were grossed at a point perpendicular to the suture path at the greatest suture depth. After grossing, the sutures were carefully removed and the tissues were processed for histologic study. Multiple sections were cut at 5 microns and routinely stained with hematoxylin and eosin. All sections were examined microscopically without the examiner knowing the type of suture material used. The tissue reaction was arbitrarily classified as mild, moderate, or severe, depending upon its intensity, nature, and extent. Selected sections were stained after the method of Brown and Brenn (B and B) and examined for the presence of bacteria. Two animals were sacrificed at 4 and 6 days, respectively. Their tissues were processed as previously described, except that the sutures were not removed
Table I T&sue response Suture material
1
Mild
1 Mod&-ate
1
Severe ---I 1 ( 4%)
.-:I’ -’ specwnens .--. 26 17 26
Nylon (monofilament) 15 (57%) 10 (39%) Surgical gut (plain) 6 (35%) 10 (59%) Chromic (medium) 12 (46%) 9 (35%) Steel (mohofih&ment) 10 (37%) 12 (44%) Silk (black braided) 7 (25%) 16 (59%) Polyester Aber (green braided) 9 (32%) 12 (43%) Cotton (white twisted) ;; 3 (11%) 15 (55%) Dermal (black twisted silk) 26 2 ( 7%) 17 (65%) Linen (natural color) 24 1 ( 5%) 15 (62%) The figures under each type of tissue response indicate the number of specimens judged representative for each response to each material. Percentages are based on the total number of tissue specimens available for each suture material. Suture materials are listed in the order of their comparative mean tissue response, based on arbitrary values of 1, 2, s,ud 3 assigned to “mild,” “moderate,” and “severe” responses.
594
Lilly
et al.
O.S., O.M. & O.P. October, 1968
when the tissues were grossed, However, the steel sutures were rcmovrd prior to histologic processing. RESULTS
In most instances, four tissue specimens were availa.ble for each suture material for each sacrifice date. Occasionally, however, sutures were lost during the postoperative, phase, and gut sutures were not present in the B- and lo-day specimens. With the noted exception of gut (at 8 and 10 days), there was a minimum of three specimens available for microscopic study in e,achinstance. The results of the microscopic examination are summarized in Table I. In general, the inflammatory response was less exaggerated than that previously observed in animals not receiving systemic antibiotics.18 The reactions associated with the sutures placed in the buccal mucosa and tongue were comparable and, therefore, will not be described separately. The tissue responses during the first three postoperative sacrifice dates (1, 2, and 3 days) were less consistent for specific suture materials than those observed in later specimens. Reactions associated with l-day specimens consisted of hemorrhage, edema,,and a mild inflammatory infiltrate which was primarily neutrophilic. There was little variability among the different types of suture materials, and most reactions were classified as moderate (Fig. 1). Specimens examined 2 and 3 days after placement of sutures exhibited divergent reactions which were more consistent for each type of suture material. Mild reactions consisted of a localized inflammatory infiltrate of neutrophils, lymphocytes, and histiocytes. Early evidence of fibroblastic activity was observed (Fig. 2). Severe reactions contained a broader zone of inflammatory reaction, with a dense infiltrate of neutrophils and little evidence of fibroblastic proliferation (Fig. 3).
1. Moderate reaction associated with cotton suture edema, hemorrhage, and diffuse inflammatory x40.) ly neutrophi lit. (Magnification, Fig.
operatively.Note
in buccal mucc ,sa, 1 day postinfiltrate which is pr edomi nant-
Volume 26 Number 4
Oral tissue reactiolz to suture materials
595
Four to 6 days after placement of sutures, mild reactions were characterized by increased fibroblastic proliferation and a circumscribed inflammatory infiltrate of lymphocytes, neutrophils, and plasma cells (Fig. 4). An occasional foreign-body giant cell was observed. These did not appear to be specific for any type of suture material. In the severe reactions, there was no evidence of significant fibroblastic proliferation or foreign-body giant cells. The inflammatory infiltrate was dense, not circumscribed, and predominantly neutrophilic. Suture abscesses, however, were not observed (Fig. 5). Eight to 10 days after placement of sutures, mild reactions exhibited progressive fibrosis and contained a mild infiltrate of plasma cells and lymphocytes (Fig. 6). Foreign-body giant cells were observed in some cases. These were not specific for any type of suture materials. Severe reactions con-
Fig. a
Fig.
3
Fig. 9. Mild reaction associated with monofilament gut suture in buccal mucosa, 3 days postoperatively, showing early evidence of fibroblastic proliferation. Note mixed inflammatory infiltrate of neutrophils, plasma cells, and lymphocytes. (Magnification, x100.) Fig. 8. Severe tissue reaction in tongue associated with multifilament braided silk, 3 days postoperatively. Note dense infiltrate of neutrophils. (Magnification, x100.)
596
Lilly
et al.
4
Fig. 5
Fig. 4. Mild reaction in bucoal mucosa to monofilament steel suture, 4 days postoperatively. Tissues are infiltrated by lymphocytes and plasma cells. (Magnification, x100.) Fig. 5. Severe reaction in tongue associated with twisted silk (Dermal), 6 days postoperatively. Note dense infiltrate of neutrophils. Void at upper right-hand corner represents suture site. (Magnification, x200.)
tained a diffuse neutrophilic inflammatory infiltrate with microabscesses (Fig. 7). Approximately one half of the specimens associated with multifilament sutures contained microabscesses. Responses that were judged to be moderate were observed at all postoperative dates. These were considered to be intermediate between the mild and the severe reactions. A detailed description of these reactions is not considered necessary. None of the sections interpreted as showing moderate rea,ctions contained microabscesses. Small particles which appeared to represent bacteria were observed in almost all sections stained by the Brown and Brenn method prepared from specimens from which the sutures had been removed prior to processing. These bacteria were usually located in the void left by the removed suture and on the mucosal
Volume 26 Number 4
Oral tissue reaction. to suture materials
Fig.
597
6
Fig. 7
Pig. 6. Mild tissue reaction associated with monofilament nylon suture in tongue, 10 days postoperatively. Numerous fibroblasts are observed, and collagen formation is evident. Note sparse inflammatory infiltrate. (Magnification, x200.) Fig. 7. Severe tissue response associated with multifilament polyester suture in tongue, 8 days postoperatively. Note dense uncircumscribed inflammatory infiltrate, which is predominantly neutrophilic. Dense cellular areas adjacent to suture site were interpreted as microabscesses. (Magnification, x40.)
surface. They were seldom identified deep within the tissue. The number of bacteria present varied considerably from one specimen to another. Although no attempt was made to correlate the number of bacteria present with the type of suture, their numbers did appear to be roughly correlated with the degree of tissue response. Brown and Brenn staining revealed that sections prepared from specimens with sutures in place contained numerous small particles within the interstices of the multifilament sutures (Fig. 8). On the basis of their morphology and staining characteristics, these particles were interpreted as bacteria. Similar particles also were observed in association with monofilament sutures. These were fewer in number, however, and did not permeate the suture.
O.H., OX 84O.P. CMobtv, 1968
Fig. 8. Cross section of multifilament braided silk suture in buccal mucost+, 6 days postoperatively. Numerous small particles between silk filaments rrcrr interpreted as bacteria. (Brown and Brenn stain. Magnification, x900.)
DISCUSSION Although the tissue response to ea.ch suture material was variable, there was sufficient consistency to permit a categorization of the different suture materials. The monofila,ment materials were associated with less severe tissue responses than the multifilament materials. This finding is the same as that reported in a previous study in which the same suture materials were placed in dogs that were not receiving systemic antibiotic therapy.ls There was some minor variation from previous findings in the relative acceptability of the sutures within the monofilament and multifilament groups. Some of this varia,tion may have been due to trauma associated with suture placement, particularly in regard to the steel suture. Although systemic antibiotics appeared to reduce the tissue response to oral sutures, they did not appreciably alter the compa,rative response to the various suture materials. These findings indicate that the tissue reaction to the placement of oral sutures is different from that reported for other anatomic locations59 Gsg, I13I2 These results provide additional s~~pport to the thesis suggested by Katz and Evans7 that the physical nature of the suture is a major factor affecting tissue response. The particles interpreted as bacteria., observed between the filaments of the multifilament suture material in sections stained by the Brown and Brenn method, suggest that variation in bactesial transmission is responsible for this difference. This, coupled with the over-all reduction in the magnitude of the tissue response observed in these animals receiving antibiotics, as compared to previous work, further suggests that bacteria, play a role in determining the tissue reaction and that certain oral sutures do act as wicks. The ability of sutures to transmit bacteria has been demonstrated in vitro in this laboratory. These studies, however, have failed to demonstrate any selective differences between the various suture materials. This failure to
Volume 26 Number 4
Oral tissue reactiost to suture materials
demonstrate differences in bacterial transmission inadequacies in our laboratory model.
is considered
599
to be due to
SUMM.ARY The response of oral tissues to nine different suture materials was studied histologically in dogs that were receiving systemic antibiotic therapy. The monofilament suture materials-nylon, gut, steel, and chromic-were associated with less severe reactions than the multifilament materials-silk (braided), polyester fiber, cotton, Dermal (twisted silk), and linen. These findings indicate that the oral tissue response is related to the physical nature of the suture and that systemic antibiotics do not appreciably alter the comparative response to various suture materials. Brown and Brenn staining of tissue sections demonstrated particles within the interstices of multifilament suture materials, suggesting that variation in the transmission of bacteria may account for the difference in tissue response. REFERENCES
1. Bellas, J. E.: Influence of Sutures Upon Operative Wounds, Ann. Surg. 112: 112-121, 1940. 2. Britt! C!. I., Miller, E. M., Felder, M. E., and Sirak, H. D.: Comparative Reaction of Mersilene and Silk Sutures Implanted Within the Heart, Ann. Surg. 153: 52-62, 1961. 3. Corm, Julius, and Beal, J. M.: Evaluation of Multistrand Stainless Steel Wire Sutures, Am. J. Surg. 103: 593596, 1962. 4. Dettinger, G. B., and Bowers, W. F.: Tissue Response to Orlon and Dacron Sutures: A Comparison With Nylon, Cotton, and Silk, Surgery 42: 325-335, 1957. 5. Gaskin, E. R., and Chdders, M. D.: Increased Granuloma Formation From Absorbable Sutures, J. A. M. A. 185: 142-144, 1963. 6. Homes, E. L.: The Strength of Wounds Sutured With Catgut and Silk, Surg. Gynec. & Obst. 57: 309-317, 1935. Sutures : An Evaluation of Tissue 7. Katz,. A. B., and Evans, H. D. : Linear Polyethylene Reaction, Am. J. Surg. 103: 208-216, 1962. 8. Large, 0. P.: Comparison of Tissue tiactions From New Sutures, Am. J. Surg. 60: 414-423, 1943. 9. Deterling, R. A., Jr., Coleman, C. C., Jr., Kee, J., and Humphreys, C. H., II: An Experimental Evaluation of Catgut as a Vascular Suture Material and a Report on Its Clinical Use, J. Thorax. Surg. 23: 303-326, 1952. 10. Latimer, E. O., and Werr, J. A.: ClinicaI Experience With Dacron as a Nonabsorbable Suture Material, Surg. Gynec. & Obst. 112: 373-374, 1961. 11. Localio, 5. A. Casale, W., and Hinton, J. W.: Wound Healing-Experimental and Statistical Study. V. Bacteriology and Pathology in Relation to Suture Material, Surg. Gynec. & Obst. 77: 481-492, 1943. 12. Madsen, E. T.: An Experimental and Clinical Evaluation of Surgical Suture Materials. II, Surg. Gynec. & Obst. 97: 439-444, 1953. 13. Narat, J. K., Cangelosi, J. P., and Belmonte, J. V.: Evaluation of Dacron Suture Material for General Surgery, Surg. Forum 7: 176-178, 1957. 14. Postlethwait, R. W., Floyd, B. J., Dillon, M. L., and Stowe, D. G.: Tissue Reaction to Blood Vessel Sutures, Am. Surg. 28: 799-801, 1962. 15. Postlethwait, R. W., Schauble, J. F., Dillon, M. L., and Morgan, J.: Wound Healing. Il. An Evaluation of Surgical Suture Material, Surg. Gynec. & Obst. 108: 555-566, 1959. 16. Postlethwait, R. W., Schauble, J. F., Dillon, M. L., and Freeman, J. Wound Healing, Arch. Surg. 78: 948961, 1959. 17. Shumacker, H. B., and Mandelbaum, I.: Clinical Evaluation of Dacron Suture Material, Arch. Surg. 83: 647-649, 1961. 18. Lilly, G. E.: Reaction of Oral Tissues to Suture Materials, ORAL Suao., On,.& MED. & On&r, PATH. 26: 128-133, 1968.