Polyvinylpyrrolidone-iodine (PVP-I) is a well-known antiseptic, widely used in various preparations and concentrations in all surgical fields. It is also used as an irrigant for open wounds and in some centres for irrigating sockets after tooth extraction. One of the authors (GA) incidentally discovered an anti-oedematous effect of PVP-I after using it in low concentration as an irrigant/coolant during the surgical removal of lower third molars. A prospective randomized clinical trial was subsequently performed on 50 patients (25 control, 25 treatment group) undergoing removal of impacted lower third molars. In the treatment group a 0.5% PVP-I solution at a concentration of 0.5 mg/ml (we call it as “Arakeri’s iodine solution”) resulted in a significant reduction in postoperative swelling compared with the control group ( P < 0.01). This effect of PVP-I was suspected due to its inhibitory effect on leukotriene B4 and leukocyte extravasation (chemotaxis). Further evaluation of the effects of PVP-I as an irrigant in oral and maxillofacial surgery is needed.
Polyvinylpyrrolidone-iodine (PVP-I) is a widely used antiseptic, introduced by Shelanski and Shelanski in 1956, which results from the combination of molecular iodine and polyvinylpyrrolidone . PVP-I irrigation is a simple and inexpensive solution, with the potential to reduce surgical site infection . The antiseptic action is attributed to its toxicity towards microorganisms as it combines irreversibly with tyrosine residues of proteins, interferes with the formation of hydrogen bonding by some amino acids and nucleic acids, oxidizes sulfydryl groups and reacts with sites of unsaturation in lipids .
It is commonly used on intact skin in preparation for surgery and on open wounds. Acute lacerations are soaked in iodine and surgical wounds are freely irrigated with it . Various studies report that PVP-I irrigation prevents surgical site infection compared with saline, water or no irrigation .
In oral and maxillofacial surgery, PVP-I is sometimes used as an irrigant for alveolar sockets following dental extraction . Its haemostatic action following extraction was investigated by K umar et al. and it has been found to have a wide application in all surgical specialties. To investigate this haemostatic property during the surgical removal of the lower third molar, diluted PVP-I was used as a coolant/irrigant by one of the authors (GA) and an incidental perceived reduction in postoperative oedema was observed. Its haemostatic effect during surgery was also evident.
The anti-inflammatory property of PVP-I when used as a topical applicant in burns is mentioned in some studies but there are no studies suggesting PVP-I as a specific anti-oedematous agent. White head varnish (iodoform, balsam tolutan and styrax liquid in a base liquid) has been shown to reduce pain, swelling and trismus after topical application to sockets following extraction . In that study, there was no mention of the possible anti-oedematous effects of iodine.
The authors undertook a prospective randomized study of 50 patients undergoing surgical removal of the lower third molars to evaluate whether there was any effect of diluted PVP-I when used as an irrigant/coolant in low concentration during the surgical procedure.
Materials and methods
Approval was obtained from the local ethical committee for the randomized clinical trial. Fifty consecutive patients (28 male, 22 female) who required surgical removal of an impacted single mandibular third molar under local anaesthesia were selected for this single blind randomized control trial.
For standardization of the sample the following clinical and radiographic criteria, modified from K umar et al. were used. The inclusion criteria were: healthy ambulatory patients (ASA class I) requiring removal of a single impacted lower third molar that necessitated mucoperiosteal flap elevation, buccal bone guttering with or without sectioning of the tooth; age 20–40 years; moderately difficult impaction (difficulty index value 5–6) based on radiographic assessment (as described by P ederson ); patients who did not have inflammation, infection or pain at the operating site in the 7 days before surgery; no history of bleeding disorders; no history of eventful previous extractions. Exclusion criteria were: patients with systemic diseases, pregnancy, breast-feeding or any therapy that could interfere with the healing process; the use of antibiotic or anti-inflammatory drugs in the 7 days before surgery; conditions, such as periodontitis, gingivitis and dental abscess; patients taking anticoagulant therapy; and history of hypersensitivity to iodine.
The patients were divided into two groups ( n = 25): the PVP-I (treatment) group; and the normal saline (control) group. After obtaining written consent, 2 ml of PVP-I 0.5% (w/v) (Bectodine, Ranbaxy, India) was diluted with 200 ml of saline (sodium chloride 0.9%, w/v; Parenteral Drugs, India) to obtain a PVP-I concentration of 0.5 mg/ml (approximately 5 × 10 −7 free iodine). This solution (Arakeri’s iodine solution) was used as an irrigant/coolant during bone guttering and tooth sectioning in the treatment group. The control group was irrigated with saline only. Procedures that exceeded more than 1 h were excluded from the study.
To minimize the operator’s variability all surgical extractions were performed by the same surgeon (GA). Third molar removal was performed in a standard way. Wound closure was achieved using 3-0 black braided silk (the standard material used in India). After the surgery details of the operation and duration of surgery (from incision to last suture) were recorded. The patients were reviewed postoperatively on days 1, 2 and 7.
Facial swelling was evaluated using a flexible tape and following a modification of the method described by S chultze -M osgau et al. Measurements were taken by marking 6 fixed points and 5 surgical base lines, to cover all possible directions for the extension of swelling ( Fig. 1 ). Using the flexible scale to follow the contour of the face, linear distances were noted. The measurements were made in the closed mouth position. Facial measurements were recorded preoperatively (the day of surgery) and postoperatively on days 1, 2 and 7. The sum of all measurements was taken as the facial size. Facial swelling for each patient at different time interval is calculated as the postoperative facial size (sum of postoperative facial measurements) minus the preoperative facial size (sum of preoperative facial measurements). The mean of facial swelling on each day was recorded and tabulated. Statistical analysis was carried out using paired and unpaired t- tests.
Postoperatively, all patients were prescribed only analgesic paracetamol 500 mg (1 tablet every 6 h for 2 days) following the authors’ routine protocol. All patients were discharged after having been given the usual postoperative instructions and advised to avoid any medications except those prescribed and not to seek medical help elsewhere for postoperative problems.
The study included 50 patients (28 males, 22 females). There were 12 males and 13 females in the treatment (PVP-I) group with a mean age of 26.8 ± 5.9 years (range 20–40 years). There were 16 males and 9 females in the control (saline) group with a mean age of 25.3 ± 3.9 years (range 20–34 years) ( Table 1 ).
|Treatment group (PVP-I)||Control group (saline)|
|No of subjects||25||25|
|Mean age ± SD||26.8 ± 5.9||25.3 ± 3.9|
The mean duration of surgery was 42.5 ± 7.5 min in the treatment group and 41.5 ± 13.5 min in the control group. The time difference in both groups was not significant ( P = 0.75) ( Table 2 ).