- Email: [email protected]
Silk and polyglycolic acid in oral surgery: A comparative study
Silk and polyglycolic acid in oral surgery: A comparative study Francesco Sortino, MD,a Claudia Lombardo, MD,a and Agata Sciacca,b Catania, Italy UNIVERSITY OF CATANIA
The inflammatory reaction caused by 2 different suture materials, black silk and polyglycolic acid, was evaluated 8 days after application and permanence in the oral environment. A randomized sample of 55 patients, aged 9 to 76, who had undergone oral urgery was examined. The suture materials (30 black silk and 25 polyglycolic acid), soon after removal, were placed in sterile containers and transferred to the laboratory. A bacterial count was carried out and the sutures were observed under light microscope (⫻100 magnification) to indirectly evaluate the inflammatory reaction. All patients were recommended to properly disinfect the wound with a 0.2% chlorhexidine solution. The inflammatory reaction of gingival tissues was lower for polyglycolic acid compared to silk sutures. However, the wound conditions, evaluated 8 days after surgery, were acceptable in patients treated with both silk and polyglycolic acid sutures. The use of chlorhexidine solution did not significantly affect the presence and type of microorganisms in either kind of suture. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2008;105:e15-e18)
During the 1960s and early 1970s great innovations were made in the field of suture materials. Thus, the development of synthetic materials has allowed the introduction of several sutures with different features, good quality, and a reasonable cost. These synthetic suture materials have been well accepted and rapidly adopted by surgeons so that they have almost completely replaced natural suture materials. However, one problem linked to the use of natural sutures, i.e., bacterial infections due to wound contamination, has not been overcome with the use of synthetic sutures. This problem can be a serious complication in patients who have undergone surgery1 and may be particularly relevant in oral surgery in which the wound is easily exposed to bacterial contamination present in the oral cavity and to saliva, food residues, ingested liquids, microorganisms, and so forth. Handling of suture materials within the oral cavity, as well as their removal, may favor spreading of bacterial infections, with the risk of more serious complications especially for patients with chronic illnesses, including diabetes and heart disease.2 It has been well established that the presence of suture material in the wound increases the risk of infection,1 a phenomenon that is more pronounced with multifilament materials. Following the first observation by Lilly,3 several studies have demona
Professor, Department of Medical-Surgical Specialties, Section of Dentistry II, University of Catania, Italy. b Department of Microbiological Sciences, University of Catania, Italy. Received for publication Jun 20, 2007; returned for revision Sep 10, 2007; accepted for publication Sep 24, 2007. 1079-2104/$ - see front matter © 2008 Mosby, Inc. All rights reserved. doi:10.1016/j.tripleo.2007.09.019
strated and confirmed a reduced inflammatory response after the application of monofilament suture materials in oral wounds compared to multifilament ones. It has been hypothesized that a “wicking” phenomenon, occurring more frequently with multifilament suture materials, could be responsible for the diffusion of the infection in the wound.3 In addition, it has been demonstrated that multifilament structure may favor the presence of bacteria in its interstices,4 thus inducing a more prolonged tissue inflammatory response.5,6 In contrast, Rothenburger et al.7 have shown that wound infection depends on suture material and its structure, but is not necessarily related to mono- or multifilament composition. However, as suggested by Altemeier and Culbertson,8 the presence of bacteria inside the wound does not necessarily implicate development of infection. It seems in fact that the risk of infection of the wound can be calculated as the ratio between bacterial contamination and its virulence and the host resistance. Elek and Cohen9 demonstrated that 7.5 million viable staphylococci are necessary to induce an intradermal infection, whereas only 300 bacteria are sufficient to produce a similar response in the presence of a silk suture. MATERIALS AND METHODS We analyzed bacterial contamination of black silk and polyglycolic acid sutures that had been in the oral cavity for 8 days. Fifty-five patients, 26 males and 29 females, aged 9 to 76, were included in the study. They were randomly divided into 2 groups: 30 treated with black silk and 25 with polyglycolic acid following an oral surgery intervention. All surgery involved the mandible angle, an aspect that has to be taken into account because of the difficulty in performing an adequate oral hygiene in the posterior e15
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Fig. 2. Presence of cells of the inflammatory reaction in materials obtained from black silk (A) and polyglycolic acid (B) sutures. Ly, lymphocytes; ep, epithelial cells; neu, neutrophils; fib, fibrin.
Fig. 1. Microscopic analysis of materials obtained from sutures after removal from the oral cavity showing the presence of different cell types. In particular, epithelial cells and cocci (A); leukocytes, epithelial cells, and cocci (B); and neutrophils, bacterioides, and fungi (C) are evident (Gram stain, magnification ⫻100).
region of the mouth following oral surgery. All patients were asked to carry out a careful cleaning of the mouth, 3 times a day with a 0.2% chlorhexidine solution, and always after eating. Eight days after surgery, sutures were removed, placed in sterile containers, and sent to laboratory for processing. After suspension in 1 mL sterile saline, 10-microliter aliquots were seeded on (1) tryptose agar with 5% blood for total count; (2) Columbia agar for anaerobic bacteria; (3) Sabouraud agar for fungi; (4) MacConkey agar for enterobacteria; and (5) mannite salt agar for staphylococci. Cultures were placed in an incubator at 37°C for 24 to 48 hours. At the same time, materials were smeared onto glass slides for Gram and Giemsa staining. All samples were then examined with a light microscope, magnification ⫻100 (Fig. 1).
RESULTS Microscopic analysis of materials obtained from 30 black silk sutures with Giemsa stain revealed the presence of inflammatory cells in almost all samples examined (29 of 30). Lymphocytes were present in 41% of samples and epithelial cells and neutrophils in 13% (Fig. 2, A). In 17% of samples, neutrophils and lymphocytes coexisted. Lymphocytes and neutrophils together with different cellular elements were prevalent in black silk when compared to polyglycolic acid sutures. In addition, in 13 (52%) of 25 polyglycolic acid samples, cells were lacking and only fibrin was visible, whereas in 12% both epithelial cells and fibrin were present (Fig. 2, B). Black silk sutures exhibited a high degree of aerobic bacteria. In particular, Streptococcus viridans, Neisseria saprofita, Corynebacterium, and Staphylococci were detected. In addition, several bacteria potentially pathogenic were present: Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus, Streptococcus pyogenes, and Enterobacterium. Finally, in 9 of 30 sutures, fungi, in particular Candida albicans, were observed (Fig. 3, A). Polyglycolic acid sutures did not show significant differences for the presence of saprophyte bacteria if compared to black silk sutures (Fig. 3, B). However, pathogenic bacteria as well as fungi were missing in polyglycolic acid sutures. Both kinds of sutures had a similar degree of anaerobic bacteria; in particular Fusobacterium nucleatus, Peptococcus, and Bacteroides melaninogenicus were observed. (Fig. 4, A, B). Unexpectedly, the use of a 0.2% chlorhexidine solu-
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Sortino et al. e17
Table I. Effect of chlorhexidine on contamination of silk and polyglycolic acid sutures Silk, % ⫹
Microorganisms Chlorhex Streptococcus viridans Neisseria Peptococcus anaerobius Fusobacterium nucleatum Candida albicans
Fig. 3. Presence of aerobic bacteria in materials obtained from black silk (A) and polyglycolic acid (B) sutures. Str vir, Streptococcus viridans; staph coag neg, Staphylococcus coagulase negative; staph au, Staphylococcus aureus; str pyo, Streptococcus pyogenes; neiss, Neisseria; cor, Corynebacterium; pseudo, Pseudomonas; enter, enterobacteria; cand alb, Candida albicans.
Fig. 4. Presence of anaerobic bacteria in materials obtained from black silk (A) and polyglycolic acid (B) sutures. Pep an, Peptococcus anaerobius; fus nuc, Fusobacterium nucleates; bac mel, Becteroides melaninogenicus.
tion did not significantly affect the pattern of bacterial contamination detected in both suture materials. In fact, although all patients were advised to use the 0.2% chlorhexidine solution several times a day, only 25% to 50% of the patients, in the silk and polyglycolic acid– treated groups, respectively, had carried out proper cleaning of the mouth at the time of suture removal, 8 days after surgery. However, as reported in Table I, the profile of bacterial contamination was similar in the 0.2% chlorhexidine–treated and – untreated groups. DISCUSSION Two different kinds of sutures can be used in surgery based on the preference of adsorbable versus nonadsorbable materials. Adsorbable sutures, because of their
Polyglycolic acid, % ⫺
Chlorhex
Chlorhex⫹ Chlorhex⫺
100
100
71
60
32 50
25 25
57 50
50 20
66
39
43
70
50
25
—
—
Comparison of profile of contaminations in black silk and polyglycolic acid sutures after exposure (chlorhex⫹) or not (chlorhex⫺) to a 0.2% chlorhexidine solution during the 8 days of maintenance of sutures in the oral cavity. Data are expressed as the percentage of sutures in each group showing the presence of the indicated microorganism.
metabolism that includes enzymatic digestion and phagocytosis, may cause a greater degree of inflammation in contrast to nonadsorbable materials that produce only a blind inflammatory response.10-12 In the present study we used 2 kinds of materials commonly used in oral surgery: black silk, a nonadsorbable suture, and polyglycolic acid, material that is adsorbed with time. This choice has been dictated by their large diffusion and because several surgeons still prefer silk sutures, as this material is considered highly reliable, handy, easy to use, and stable for the duration of suture. However, silk sutures are known to cause a rather strong inflammatory response, due to the specific molecular composition and to the structure that represents a good recipient for bacteria. Polyglycolic acid sutures, on the other hand, are frequently used even if their performance is not comparable to that of silk sutures and although oral surgery only rarely requires the use of absorbable materials. The preference toward silk by oral surgeons is also because polyglycolic acid, if not removed, requires time for its reabsorption,13 a condition that may favor inflammatory events. In the present study we evaluated the microbiological features of the 2 suture materials and they were related to the wound conditions upon removal of the suture. All materials analyzed were removed 8 days after surgery. The wounds were considered in good state in both study groups independently of the presence of different bacteria. The inflammatory reaction was more restricted in patients treated with polyglycolic acid sutures, as from the presence of inflammatory cells in this suture material. Accordingly, despite a similar presence of anaerobic and aerobic bacteria, potentially patho-
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Sortino et al.
genic microorganisms as well as fungi were missing in polyglycolic acid sutures. In addition, contamination was not affected by daily use of the 0.2% chlorhexidine solution. In fact, a detailed analysis on the presence of microorganisms in sutures from chlorhexidine-treated and -untreated patients did not show any significant difference in most cases. Surprisingly, when differences were present, they did not show any reduction by chlorhexidine. Accordingly, no clear relationship was apparent between the incidence of bacteremia and the preprocedural use of an oral rinse with a 0.12% chlorhexidine solution after intraoral suture removal.14 In addition, it has been reported that placement of sutures in gingival induces an inflammatory reaction regardless of antiinfective therapy.15 In conclusion, the slightly better performances obtained with polyglycolic acid in the present study may be balanced by the better tension exhibited by black silk sutures (data not shown), making a definite choice between one or the other suture material in oral surgery difficult. REFERENCES 1. Chu CC, Williams DF. Effects of physical configuration and chemical structure of suture materials on bacterial adhesion. Am J Surg 1984;147:197-204. 2. King RC, Crawford JJ, Small EW. Bacteremia following intraoral suture removal. Oral Surg Oral Med Oral Pathol 1988; 65:23-8. 3. Lilly GE. Reaction of oral tissues to suture materials. Oral Surg Oral Med Oral Pathol 1968;26:128-33. 4. Lilly GE, Armstrong JH, Salem JE, Cutcher JL. Reaction of oral tissues to suture materials. II. Oral Surg Oral Med Oral Pathol 1968;26:592-9.
5. Durdley P, Bucknall TE. Assessment of sutures for use in colonic surgery: an experimental study. J R Soc Med 1984;77:472-7. 6. Grigg TR, Liewer FR, Patton WR, Buxton TB, McPherson JC. Effect of the wicking behaviour of multifilament sutures. J Endod 2004;30:649-52. 7. Rothenburger S, Spangler D, Bhende S, Burkley D. In vitro antimicrobial evaluation of coated Vicryl plus antibacterial suture (coated polyglactin 910 with triclosan) using zone inhibition assays. Surg Infect 2002;3:79-87. 8. Altemeier WA, Culberston WR. Surgical infection. In: Moyer CA, Rhoads JE, Allen JG, Harkins HN, eds. Surgery, principles and practice. Ed 3. Philadelphia: Lippincott; 1965. p. 51-77. 9. Elek SD, Cohen PE. The virulence of S. pyogenes for man. A study of the problems of wound infection. Br J Exp Pathol 1957;38:573-86. 10. Yaltirik M, Dedeoglu K, Bilgic B. Comparison of four different suture materials in soft tissue of rats. Oral Dis 2003;9:284-7. 11. Greenwald D, Shumway S, Albear P, Gottlieb L. Mechanical comparison of 10 suture materials before and after in vivo incubation. J Surg Res 1994;56:372-7. 12. Giray CB. Clinical and electron microscope comparison of silk sutures and n butyl-2-cyanoacrylate in human mucosa. Aust Dent J 1997;42:255-8. 13. Shaw RJ, Negus TW, Mellor TK. A prospective clinical evalutation of the longevity of resorbable sutures in oral mucosa. Br J Oral Maxillofacial Surg 1996;34:252-4. 14. Brown AR, Papasian CJ, Shultz P, Theisen FC, Shultz RE. Bacteremia and intraoral suture removal: can an antimicrobial rinse help? J Am Dent Assoc 1998;129:1455-61. 15. Leknes KN, Selvig KA, Boe OE, Wikesjo UME. Tissue reaction to sutures in the presence and absence of anti-infective therapy. J Clin Periodontol 2005;32:130-8. Reprint requests: Francesco Sortino, MD c/o Clinica Odontoiatrica Via s. Sofia 78 95123 Catania, Italy [email protected]
The inflammatory reaction caused by 2 different suture materials, black silk and polyglycolic acid, was evaluated 8 days after application and permanence in the oral environment. A randomized sample of 55 patients, aged 9 to 76, who had undergone oral urgery was examined. The suture materials (30 black silk and 25 polyglycolic acid), soon after removal, were placed in sterile containers and transferred to the laboratory. A bacterial count was carried out and the sutures were observed under light microscope (⫻100 magnification) to indirectly evaluate the inflammatory reaction. All patients were recommended to properly disinfect the wound with a 0.2% chlorhexidine solution. The inflammatory reaction of gingival tissues was lower for polyglycolic acid compared to silk sutures. However, the wound conditions, evaluated 8 days after surgery, were acceptable in patients treated with both silk and polyglycolic acid sutures. The use of chlorhexidine solution did not significantly affect the presence and type of microorganisms in either kind of suture. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2008;105:e15-e18)
During the 1960s and early 1970s great innovations were made in the field of suture materials. Thus, the development of synthetic materials has allowed the introduction of several sutures with different features, good quality, and a reasonable cost. These synthetic suture materials have been well accepted and rapidly adopted by surgeons so that they have almost completely replaced natural suture materials. However, one problem linked to the use of natural sutures, i.e., bacterial infections due to wound contamination, has not been overcome with the use of synthetic sutures. This problem can be a serious complication in patients who have undergone surgery1 and may be particularly relevant in oral surgery in which the wound is easily exposed to bacterial contamination present in the oral cavity and to saliva, food residues, ingested liquids, microorganisms, and so forth. Handling of suture materials within the oral cavity, as well as their removal, may favor spreading of bacterial infections, with the risk of more serious complications especially for patients with chronic illnesses, including diabetes and heart disease.2 It has been well established that the presence of suture material in the wound increases the risk of infection,1 a phenomenon that is more pronounced with multifilament materials. Following the first observation by Lilly,3 several studies have demona
Professor, Department of Medical-Surgical Specialties, Section of Dentistry II, University of Catania, Italy. b Department of Microbiological Sciences, University of Catania, Italy. Received for publication Jun 20, 2007; returned for revision Sep 10, 2007; accepted for publication Sep 24, 2007. 1079-2104/$ - see front matter © 2008 Mosby, Inc. All rights reserved. doi:10.1016/j.tripleo.2007.09.019
strated and confirmed a reduced inflammatory response after the application of monofilament suture materials in oral wounds compared to multifilament ones. It has been hypothesized that a “wicking” phenomenon, occurring more frequently with multifilament suture materials, could be responsible for the diffusion of the infection in the wound.3 In addition, it has been demonstrated that multifilament structure may favor the presence of bacteria in its interstices,4 thus inducing a more prolonged tissue inflammatory response.5,6 In contrast, Rothenburger et al.7 have shown that wound infection depends on suture material and its structure, but is not necessarily related to mono- or multifilament composition. However, as suggested by Altemeier and Culbertson,8 the presence of bacteria inside the wound does not necessarily implicate development of infection. It seems in fact that the risk of infection of the wound can be calculated as the ratio between bacterial contamination and its virulence and the host resistance. Elek and Cohen9 demonstrated that 7.5 million viable staphylococci are necessary to induce an intradermal infection, whereas only 300 bacteria are sufficient to produce a similar response in the presence of a silk suture. MATERIALS AND METHODS We analyzed bacterial contamination of black silk and polyglycolic acid sutures that had been in the oral cavity for 8 days. Fifty-five patients, 26 males and 29 females, aged 9 to 76, were included in the study. They were randomly divided into 2 groups: 30 treated with black silk and 25 with polyglycolic acid following an oral surgery intervention. All surgery involved the mandible angle, an aspect that has to be taken into account because of the difficulty in performing an adequate oral hygiene in the posterior e15
e16
Sortino et al.
OOOOE March 2008
Fig. 2. Presence of cells of the inflammatory reaction in materials obtained from black silk (A) and polyglycolic acid (B) sutures. Ly, lymphocytes; ep, epithelial cells; neu, neutrophils; fib, fibrin.
Fig. 1. Microscopic analysis of materials obtained from sutures after removal from the oral cavity showing the presence of different cell types. In particular, epithelial cells and cocci (A); leukocytes, epithelial cells, and cocci (B); and neutrophils, bacterioides, and fungi (C) are evident (Gram stain, magnification ⫻100).
region of the mouth following oral surgery. All patients were asked to carry out a careful cleaning of the mouth, 3 times a day with a 0.2% chlorhexidine solution, and always after eating. Eight days after surgery, sutures were removed, placed in sterile containers, and sent to laboratory for processing. After suspension in 1 mL sterile saline, 10-microliter aliquots were seeded on (1) tryptose agar with 5% blood for total count; (2) Columbia agar for anaerobic bacteria; (3) Sabouraud agar for fungi; (4) MacConkey agar for enterobacteria; and (5) mannite salt agar for staphylococci. Cultures were placed in an incubator at 37°C for 24 to 48 hours. At the same time, materials were smeared onto glass slides for Gram and Giemsa staining. All samples were then examined with a light microscope, magnification ⫻100 (Fig. 1).
RESULTS Microscopic analysis of materials obtained from 30 black silk sutures with Giemsa stain revealed the presence of inflammatory cells in almost all samples examined (29 of 30). Lymphocytes were present in 41% of samples and epithelial cells and neutrophils in 13% (Fig. 2, A). In 17% of samples, neutrophils and lymphocytes coexisted. Lymphocytes and neutrophils together with different cellular elements were prevalent in black silk when compared to polyglycolic acid sutures. In addition, in 13 (52%) of 25 polyglycolic acid samples, cells were lacking and only fibrin was visible, whereas in 12% both epithelial cells and fibrin were present (Fig. 2, B). Black silk sutures exhibited a high degree of aerobic bacteria. In particular, Streptococcus viridans, Neisseria saprofita, Corynebacterium, and Staphylococci were detected. In addition, several bacteria potentially pathogenic were present: Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus, Streptococcus pyogenes, and Enterobacterium. Finally, in 9 of 30 sutures, fungi, in particular Candida albicans, were observed (Fig. 3, A). Polyglycolic acid sutures did not show significant differences for the presence of saprophyte bacteria if compared to black silk sutures (Fig. 3, B). However, pathogenic bacteria as well as fungi were missing in polyglycolic acid sutures. Both kinds of sutures had a similar degree of anaerobic bacteria; in particular Fusobacterium nucleatus, Peptococcus, and Bacteroides melaninogenicus were observed. (Fig. 4, A, B). Unexpectedly, the use of a 0.2% chlorhexidine solu-
OOOOE Volume 105, Number 3
Sortino et al. e17
Table I. Effect of chlorhexidine on contamination of silk and polyglycolic acid sutures Silk, % ⫹
Microorganisms Chlorhex Streptococcus viridans Neisseria Peptococcus anaerobius Fusobacterium nucleatum Candida albicans
Fig. 3. Presence of aerobic bacteria in materials obtained from black silk (A) and polyglycolic acid (B) sutures. Str vir, Streptococcus viridans; staph coag neg, Staphylococcus coagulase negative; staph au, Staphylococcus aureus; str pyo, Streptococcus pyogenes; neiss, Neisseria; cor, Corynebacterium; pseudo, Pseudomonas; enter, enterobacteria; cand alb, Candida albicans.
Fig. 4. Presence of anaerobic bacteria in materials obtained from black silk (A) and polyglycolic acid (B) sutures. Pep an, Peptococcus anaerobius; fus nuc, Fusobacterium nucleates; bac mel, Becteroides melaninogenicus.
tion did not significantly affect the pattern of bacterial contamination detected in both suture materials. In fact, although all patients were advised to use the 0.2% chlorhexidine solution several times a day, only 25% to 50% of the patients, in the silk and polyglycolic acid– treated groups, respectively, had carried out proper cleaning of the mouth at the time of suture removal, 8 days after surgery. However, as reported in Table I, the profile of bacterial contamination was similar in the 0.2% chlorhexidine–treated and – untreated groups. DISCUSSION Two different kinds of sutures can be used in surgery based on the preference of adsorbable versus nonadsorbable materials. Adsorbable sutures, because of their
Polyglycolic acid, % ⫺
Chlorhex
Chlorhex⫹ Chlorhex⫺
100
100
71
60
32 50
25 25
57 50
50 20
66
39
43
70
50
25
—
—
Comparison of profile of contaminations in black silk and polyglycolic acid sutures after exposure (chlorhex⫹) or not (chlorhex⫺) to a 0.2% chlorhexidine solution during the 8 days of maintenance of sutures in the oral cavity. Data are expressed as the percentage of sutures in each group showing the presence of the indicated microorganism.
metabolism that includes enzymatic digestion and phagocytosis, may cause a greater degree of inflammation in contrast to nonadsorbable materials that produce only a blind inflammatory response.10-12 In the present study we used 2 kinds of materials commonly used in oral surgery: black silk, a nonadsorbable suture, and polyglycolic acid, material that is adsorbed with time. This choice has been dictated by their large diffusion and because several surgeons still prefer silk sutures, as this material is considered highly reliable, handy, easy to use, and stable for the duration of suture. However, silk sutures are known to cause a rather strong inflammatory response, due to the specific molecular composition and to the structure that represents a good recipient for bacteria. Polyglycolic acid sutures, on the other hand, are frequently used even if their performance is not comparable to that of silk sutures and although oral surgery only rarely requires the use of absorbable materials. The preference toward silk by oral surgeons is also because polyglycolic acid, if not removed, requires time for its reabsorption,13 a condition that may favor inflammatory events. In the present study we evaluated the microbiological features of the 2 suture materials and they were related to the wound conditions upon removal of the suture. All materials analyzed were removed 8 days after surgery. The wounds were considered in good state in both study groups independently of the presence of different bacteria. The inflammatory reaction was more restricted in patients treated with polyglycolic acid sutures, as from the presence of inflammatory cells in this suture material. Accordingly, despite a similar presence of anaerobic and aerobic bacteria, potentially patho-
e18
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Sortino et al.
genic microorganisms as well as fungi were missing in polyglycolic acid sutures. In addition, contamination was not affected by daily use of the 0.2% chlorhexidine solution. In fact, a detailed analysis on the presence of microorganisms in sutures from chlorhexidine-treated and -untreated patients did not show any significant difference in most cases. Surprisingly, when differences were present, they did not show any reduction by chlorhexidine. Accordingly, no clear relationship was apparent between the incidence of bacteremia and the preprocedural use of an oral rinse with a 0.12% chlorhexidine solution after intraoral suture removal.14 In addition, it has been reported that placement of sutures in gingival induces an inflammatory reaction regardless of antiinfective therapy.15 In conclusion, the slightly better performances obtained with polyglycolic acid in the present study may be balanced by the better tension exhibited by black silk sutures (data not shown), making a definite choice between one or the other suture material in oral surgery difficult. REFERENCES 1. Chu CC, Williams DF. Effects of physical configuration and chemical structure of suture materials on bacterial adhesion. Am J Surg 1984;147:197-204. 2. King RC, Crawford JJ, Small EW. Bacteremia following intraoral suture removal. Oral Surg Oral Med Oral Pathol 1988; 65:23-8. 3. Lilly GE. Reaction of oral tissues to suture materials. Oral Surg Oral Med Oral Pathol 1968;26:128-33. 4. Lilly GE, Armstrong JH, Salem JE, Cutcher JL. Reaction of oral tissues to suture materials. II. Oral Surg Oral Med Oral Pathol 1968;26:592-9.
5. Durdley P, Bucknall TE. Assessment of sutures for use in colonic surgery: an experimental study. J R Soc Med 1984;77:472-7. 6. Grigg TR, Liewer FR, Patton WR, Buxton TB, McPherson JC. Effect of the wicking behaviour of multifilament sutures. J Endod 2004;30:649-52. 7. Rothenburger S, Spangler D, Bhende S, Burkley D. In vitro antimicrobial evaluation of coated Vicryl plus antibacterial suture (coated polyglactin 910 with triclosan) using zone inhibition assays. Surg Infect 2002;3:79-87. 8. Altemeier WA, Culberston WR. Surgical infection. In: Moyer CA, Rhoads JE, Allen JG, Harkins HN, eds. Surgery, principles and practice. Ed 3. Philadelphia: Lippincott; 1965. p. 51-77. 9. Elek SD, Cohen PE. The virulence of S. pyogenes for man. A study of the problems of wound infection. Br J Exp Pathol 1957;38:573-86. 10. Yaltirik M, Dedeoglu K, Bilgic B. Comparison of four different suture materials in soft tissue of rats. Oral Dis 2003;9:284-7. 11. Greenwald D, Shumway S, Albear P, Gottlieb L. Mechanical comparison of 10 suture materials before and after in vivo incubation. J Surg Res 1994;56:372-7. 12. Giray CB. Clinical and electron microscope comparison of silk sutures and n butyl-2-cyanoacrylate in human mucosa. Aust Dent J 1997;42:255-8. 13. Shaw RJ, Negus TW, Mellor TK. A prospective clinical evalutation of the longevity of resorbable sutures in oral mucosa. Br J Oral Maxillofacial Surg 1996;34:252-4. 14. Brown AR, Papasian CJ, Shultz P, Theisen FC, Shultz RE. Bacteremia and intraoral suture removal: can an antimicrobial rinse help? J Am Dent Assoc 1998;129:1455-61. 15. Leknes KN, Selvig KA, Boe OE, Wikesjo UME. Tissue reaction to sutures in the presence and absence of anti-infective therapy. J Clin Periodontol 2005;32:130-8. Reprint requests: Francesco Sortino, MD c/o Clinica Odontoiatrica Via s. Sofia 78 95123 Catania, Italy [email protected]