Comparative evaluation of the efficacy of probiotic, Aloe vera, povidine-iodine, and chlorhexidine mouthwashes in the treatment of gingival inflammation: A randomized controlled trial.

BACKGROUND: Chemical plaque control with mouthwashes as an adjunct to mechanical plaque control with a toothbrush and dental floss has been considered an effective method for controlling gingivitis. The anti-inflammatory effects of chemical plaque control benefit the oral tissues by reducing inflammation and bleeding. OBJECTIVES: The aim of the present study was to evaluate and compare the clinical efficacy of probiotic, Aloe vera, povidine-iodine, and chlorhexidine (CHX) mouthwashes in treating gingivitis patients by assessing changes in their clinical parameters. MATERIAL AND METHODS: This prospective study was conducted on 40 patients from our outpatient department, divided into 4 groups of 10 patients each: probiotic mouthwash group (group 1); herbal (Aloe vera) mouthwash group (group 2); povidone-iodine mouthwash group (group 3); and CHX mouthwash group (group 4). All participants were provided with the same type of manual toothbrush, the Pepsodent® toothpaste and a respective mouthwash for twice-daily use until the end of a 28-day observation period. Clinical parameters, such as the marginal plaque index (MPI) and bleeding on interdental brushing (BOIB), were recorded at baseline, and on the 14th and 28th day of the study period. RESULTS: All groups showed a significant decrease in the MPI and BOIB scores. The results were similar in patients who used a probiotic mouthwash and those who used a CHX mouthwash. A comparable change in the mean scores was observed among the herbal and povidone-iodine groups from baseline to day 28. CONCLUSIONS: In the treatment of chronic gingivitis patients,a probiotic mouthwash was nearly as effective as CHX in reducing the plaque and bleeding scores. It showed better results in all clinical parameters than herbal and povidone-iodine mouthwashes. Using a mouthwash along with routine tooth brushing can help in treating gingivitis and slow the progression of the periodontal disease.

Skin Antisepsis before Surgical Fixation of Extremity Fractures.

BACKGROUND: Studies evaluating surgical-site infection have had conflicting results with respect to the use of alcohol solutions containing iodine povacrylex or chlorhexidine gluconate as skin antisepsis before surgery to repair a fractured limb (i.e., an extremity fracture). METHODS: In a cluster-randomized, crossover trial at 25 hospitals in the United States and Canada, we randomly assigned hospitals to use a solution of 0.7% iodine povacrylex in 74% isopropyl alcohol (iodine group) or 2% chlorhexidine gluconate in 70% isopropyl alcohol (chlorhexidine group) as preoperative antisepsis for surgical procedures to repair extremity fractures. Every 2 months, the hospitals alternated interventions. Separate populations of patients with either open or closed fractures were enrolled and included in the analysis. The primary outcome was surgical-site infection, which included superficial incisional infection within 30 days or deep incisional or organ-space infection within 90 days. The secondary outcome was unplanned reoperation for fracture-healing complications. RESULTS: A total of 6785 patients with a closed fracture and 1700 patients with an open fracture were included in the trial. In the closed-fracture population, surgical-site infection occurred in 77 patients (2.4%) in the iodine group and in 108 patients (3.3%) in the chlorhexidine group (odds ratio, 0.74; 95% confidence interval [CI], 0.55 to 1.00; P = 0.049). In the open-fracture population, surgical-site infection occurred in 54 patients (6.5%) in the iodine group and in 60 patients (7.3%) in the chlorhexidine group (odd ratio, 0.86; 95% CI, 0.58 to 1.27; P = 0.45). The frequencies of unplanned reoperation, 1-year outcomes, and serious adverse events were similar in the two groups. CONCLUSIONS: Among patients with closed extremity fractures, skin antisepsis with iodine povacrylex in alcohol resulted in fewer surgical-site infections than antisepsis with chlorhexidine gluconate in alcohol. In patients with open fractures, the results were similar in the two groups. (Funded by the Patient-Centered Outcomes Research Institute and the Canadian Institutes of Health Research; PREPARE ClinicalTrials.gov number, NCT03523962.).

Nasal Iodophor Antiseptic vs Nasal Mupirocin Antibiotic in the Setting of Chlorhexidine Bathing to Prevent Infections in Adult ICUs: A Randomized Clinical Trial.

Importance: Universal nasal mupirocin plus chlorhexidine gluconate (CHG) bathing in intensive care units (ICUs) prevents methicillin-resistant Staphylococcus aureus (MRSA) infections and all-cause bloodstream infections. Antibiotic resistance to mupirocin has raised questions about whether an antiseptic could be advantageous for ICU decolonization. Objective: To compare the effectiveness of iodophor vs mupirocin for universal ICU nasal decolonization in combination with CHG bathing. Design, Setting, and Participants: Two-group noninferiority, pragmatic, cluster-randomized trial conducted in US community hospitals, all of which used mupirocin-CHG for universal decolonization in ICUs at baseline. Adult ICU patients in 137 randomized hospitals during baseline (May 1, 2015-April 30, 2017) and intervention (November 1, 2017-April 30, 2019) were included. Intervention: Universal decolonization involving switching to iodophor-CHG (intervention) or continuing mupirocin-CHG (baseline). Main Outcomes and Measures: ICU-attributable S aureus clinical cultures (primary outcome), MRSA clinical cultures, and all-cause bloodstream infections were evaluated using proportional hazard models to assess differences from baseline to intervention periods between the strategies. Results were also compared with a 2009-2011 trial of mupirocin-CHG vs no decolonization in the same hospital network. The prespecified noninferiority margin for the primary outcome was 10%. Results: Among the 801 668 admissions in 233 ICUs, the participants' mean (SD) age was 63.4 (17.2) years, 46.3% were female, and the mean (SD) ICU length of stay was 4.8 (4.7) days. Hazard ratios (HRs) for S aureus clinical isolates in the intervention vs baseline periods were 1.17 for iodophor-CHG (raw rate: 5.0 vs 4.3/1000 ICU-attributable days) and 0.99 for mupirocin-CHG (raw rate: 4.1 vs 4.0/1000 ICU-attributable days) (HR difference in differences significantly lower by 18.4% [95% CI, 10.7%-26.6%] for mupirocin-CHG, P < .001). For MRSA clinical cultures, HRs were 1.13 for iodophor-CHG (raw rate: 2.3 vs 2.1/1000 ICU-attributable days) and 0.99 for mupirocin-CHG (raw rate: 2.0 vs 2.0/1000 ICU-attributable days) (HR difference in differences significantly lower by 14.1% [95% CI, 3.7%-25.5%] for mupirocin-CHG, P = .007). For all-pathogen bloodstream infections, HRs were 1.00 (2.7 vs 2.7/1000) for iodophor-CHG and 1.01 (2.6 vs 2.6/1000) for mupirocin-CHG (nonsignificant HR difference in differences, -0.9% [95% CI, -9.0% to 8.0%]; P = .84). Compared with the 2009-2011 trial, the 30-day relative reduction in hazards in the mupirocin-CHG group relative to no decolonization (2009-2011 trial) were as follows: S aureus clinical cultures (current trial: 48.1% [95% CI, 35.6%-60.1%]; 2009-2011 trial: 58.8% [95% CI, 47.5%-70.7%]) and bloodstream infection rates (current trial: 70.4% [95% CI, 62.9%-77.8%]; 2009-2011 trial: 60.1% [95% CI, 49.1%-70.7%]). Conclusions and Relevance: Nasal iodophor antiseptic did not meet criteria to be considered noninferior to nasal mupirocin antibiotic for the outcome of S aureus clinical cultures in adult ICU patients in the context of daily CHG bathing. In addition, the results were consistent with nasal iodophor being inferior to nasal mupirocin. Trial Registration: ClinicalTrials.gov Identifier: NCT03140423.

Decolonization in Nursing Homes to Prevent Infection and Hospitalization.

BACKGROUND: Nursing home residents are at high risk for infection, hospitalization, and colonization with multidrug-resistant organisms. METHODS: We performed a cluster-randomized trial of universal decolonization as compared with routine-care bathing in nursing homes. The trial included an 18-month baseline period and an 18-month intervention period. Decolonization entailed the use of chlorhexidine for all routine bathing and showering and administration of nasal povidone-iodine twice daily for the first 5 days after admission and then twice daily for 5 days every other week. The primary outcome was transfer to a hospital due to infection. The secondary outcome was transfer to a hospital for any reason. An intention-to-treat (as-assigned) difference-in-differences analysis was performed for each outcome with the use of generalized linear mixed models to compare the intervention period with the baseline period across trial groups. RESULTS: Data were obtained from 28 nursing homes with a total of 28,956 residents. Among the transfers to a hospital in the routine-care group, 62.2% (the mean across facilities) were due to infection during the baseline period and 62.6% were due to infection during the intervention period (risk ratio, 1.00; 95% confidence interval [CI], 0.96 to 1.04). The corresponding values in the decolonization group were 62.9% and 52.2% (risk ratio, 0.83; 95% CI, 0.79 to 0.88), for a difference in risk ratio, as compared with routine care, of 16.6% (95% CI, 11.0 to 21.8; P<0.001). Among the discharges from the nursing home in the routine-care group, transfer to a hospital for any reason accounted for 36.6% during the baseline period and for 39.2% during the intervention period (risk ratio, 1.08; 95% CI, 1.04 to 1.12). The corresponding values in the decolonization group were 35.5% and 32.4% (risk ratio, 0.92; 95% CI, 0.88 to 0.96), for a difference in risk ratio, as compared with routine care, of 14.6% (95% CI, 9.7 to 19.2). The number needed to treat was 9.7 to prevent one infection-related hospitalization and 8.9 to prevent one hospitalization for any reason. CONCLUSIONS: In nursing homes, universal decolonization with chlorhexidine and nasal iodophor led to a significantly lower risk of transfer to a hospital due to infection than routine care. (Funded by the Agency for Healthcare Research and Quality; Protect ClinicalTrials.gov number, NCT03118232.).

Effect Of Elastomeric Separator On Microbial Count In Gingival Crevicular Fluid.

BACKGROUND: The separators are a preliminary step for band insertion, but there is a potential risk of bacteraemia during their placement, particularly in susceptible patients. The objective of the study is to determine the effect of separators on the bacterial count in gingival crevicular fluid (GCF) and to assess the efficacy of chlorhexidine mouth rinse and saline irrigation in the reduction of the bacterial count. METHODS: This randomized controlled trial was conducted on 51 participants who were divided into three equal g roups randomly (brushing only/control, saline irrigation, and 2% chlorhexidine mouthwash rinse). The inclusion criteria were age between 18-25 years, good oral hygiene, gingival and plaque index <1, no previous orthodontic treatment, and healthy individuals. The bacterial count was obtained from GCF samples after two hours, on the third day, and on the seventh day. Kruskal Wallis test was used to compare the bacterial count among the three groups, and post hoc analysis was done using Dunn's test. Friedman test was applied to see the difference at three-time points in each group. RESULTS: In both saline and chlorhexidine groups the mean bacterial count decreased significantly from baseline to 3rd day and 7th day after separator placement (p<0.001). For the third day, a significant difference was found in control versus saline and control versus chlorhexidine. No significant difference was found between saline and chlorhexidine on the third day. Similar results were found on the 7 thday. For controls, the bacterial count increased with time and for both saline and chlorhexidine groups the bacterial count decreased. The highest decrease in the bacterial count was found for the chlorhexidine group. CONCLUSIONS: After the placement of separators, there was an increase in the bacterial count in GCF. Notably, chlorhexidine was found to be more effective than saline irrigation in reducing the bacterial count.

Acute central corneal haze and thinning with atypical keratitis presentation.

A 24-year-old woman presented with a 7-day history of blurry vision, redness, and extreme pain in her right eye. She had no pertinent medical or ocular history and did not use spectacles or contacts. Uncorrected distance visual acuity (UDVA) was 20/40 in the right eye and could not be improved with refraction. Slitlamp examination revealed a 1.5 × 1.5 mm central epithelial defect with surrounding white blood cell recruitment. Confocal microscopy (Figure 1JOURNAL/jcrs/04.03/02158034-202304000-00020/figure1/v/2023-03-24T200747Z/r/image-tiff) was performed, and she was treated with chlorhexidine 0.02% drops every hour in the right eye. 2 weeks later, the cornea had completely re-epithelialized; however, persistent corneal haze, decreased visual acuity, and corneal thinning and flattening was noted. Pachymetry was 484 µm in the right eye and UDVA was 20/40 (Supplemental Figure 1, available at http://links.lww.com/JRS/A836). In the following 2 weeks, UDVA improved to 20/25. 6 months after the initial presentation, UDVA was unchanged and faint central corneal haze was noted on examination (Figure 2JOURNAL/jcrs/04.03/02158034-202304000-00020/figure2/v/2023-03-24T200747Z/r/image-tiff). Of interest, her family history is significant for her younger 16-year-old brother with 3 prior episodes of a similar type of keratitis/keratopathy over the course of 2 years in both eyes with similar central paracentral corneal haze, thinning, and flattening and similar confocal findings (Figure 3JOURNAL/jcrs/04.03/02158034-202304000-00020/figure3/v/2023-03-24T200747Z/r/image-tiff). He also was unresponsive to topical antibiotics and antivirals except topical chlorhexidine. Her brother has been our patient for the last several years prior to her first visit to our clinic. What is your diagnosis? What medical diagnostic tests, if any, would you recommend? Is this an infectious or simply an inflammatory response? Is there any genetic or familial predisposition?

Should oral chlorhexidine remain in ventilator-associated pneumonia prevention bundles?

Ventilator-associated pneumonia (VAP) is related with high mortality, duration of mechanical ventilation and costs. Recent studies have questioned the safety and effectiveness of oral chlorhexidine to prevent VAP. We sought to verify whether the adverse effects of this substance outweigh its benefits. We searched several databases and selected studies that investigated the use of oral chlorhexidine and its impact on mortality. No association between oral chlorhexidine and lower VAP rates was found on meta-analyses of double-blind randomized trials, however significant increase in mortality was reported. It is speculated that chlorhexidine can cause damage to several organic sectors and cytotoxicity. Although it still can be beneficial in specific settings, robust evidence to recommend its routine application for all mechanically ventilated patients is lacking; therefore, given the possibility of harm, it would be better to follow the principle of non-maleficence until more studies becomes available.

A Mice Model of Chlorhexidine Gluconate-Induced Peritoneal Damage.

Peritoneal fibrosis is an important complication of peritoneal dialysis (PD). To investigate and address this problem, an appropriate animal model of PD is required. The present protocol establishes a chlorhexidine gluconate (CG) induced peritoneal fibrosis model that mimics the condition of a patient with PD. Peritoneal fibrosis was induced by intraperitoneal injection of 0.1% of CG in 15% ethanol for 3 weeks (administered every other day), for a total of nine times in male C57BL/6 mice. Peritoneal functional tests were then performed on day 22. After the mice were sacrificed, the parietal peritoneum of the abdominal wall and the visceral peritoneum of the liver were harvested. They were thicker and more fibrotic when analyzed microscopically after Masson's trichrome staining. The ultrafiltration rate decreased, and glucose mass transport indicated a CG-induced increase in peritoneal permeability. The PD model thus established may have applications in improving PD technology, dialysis efficacy, and prolonging patient survival.

Should oral chlorhexidine remain in ventilator-associated pneumonia prevention bundles? / ¿Debe permanecer la clorhexidina oral en los paquetes de prevención de la neumonía asociada al respirador?

Ventilator-associated pneumonia (VAP) is related with high mortality, duration of mechanical ventilation and costs. Recent studies have questioned the safety and effectiveness of oral chlorhexidine to prevent VAP. We sought to verify whether the adverse effects of this substance outweigh its benefits. We searched several databases and selected studies that investigated the use of oral chlorhexidine and its impact on mortality. No association between oral chlorhexidine and lower VAP rates was found on meta-analyses of double-blind randomized trials, however significant increase in mortality was reported. It is speculated that chlorhexidine can cause damage to several organic sectors and cytotoxicity. Although it still can be beneficial in specific settings, robust evidence to recommend its routine application for all mechanically ventilated patients is lacking; therefore, given the possibility of harm, it would be better to follow the principle of non-maleficence until more studies becomes available (AU)

La neumonía asociada al respirador (VAP) está relacionada con una elevada mortalidad, mayor duración de la ventilación mecánica y costes elevados. Estudios recientes han cuestionado la seguridad y la eficacia de la clorhexidina oral para prevenir la VAP. Hemos intentado verificar si los efectos adversos de esta sustancia superan sus beneficios. Se realizaron búsquedas en diversas bases de datos y se seleccionaron estudios que habían investigado el uso de la clorhexidina oral y su impacto sobre la mortalidad. En los metaanálisis de los ensayos aleatorizados a doble ciego no se encontró ninguna asociación entre clorhexidina oral y tasas de VAP más bajas; sin embargo, sí se informó de un aumento significativo de la mortalidad. Se especula que la clorhexidina puede causar daño a varias partes del organismo y citotoxicidad. Pese a que todavía podría ser beneficiosa en entornos específicos, no se dispone de evidencias sólidas para recomendar su aplicación rutinaria para todos los pacientes sometidos a ventilación mecánica; por lo tanto, dada la posibilidad de ocasionar daños, sería mejor seguir el principio de no maleficencia hasta que se disponga de más estudios (AU)

Effect of pH-sensitive nanoparticles on inhibiting oral biofilms.

Dental caries is a biofilm-related preventable infectious disease caused by interactions between the oral bacteria and the host's dietary sugars. As the microenvironments in cariogenic biofilms are often acidic, pH-sensitive drug delivery systems have become innovative materials for dental caries prevention in recent years. In the present study, poly(DMAEMA-co-HEMA) was used as a pH-sensitive carrier to synthesize a chlorhexidine (CHX)-loaded nanomaterial (p(DH)@CHX). In vitro, p(DH)@CHX exhibited good pH sensitivity and a sustained and high CHX release rate in the acidic environment. It also exhibited lower cytotoxicity against human oral keratinocytes (HOKs) compared to free CHX. Besides, compared with free CHX, p(DH)@CHX showed the same antibacterial effects on S. mutans biofilms. In addition, it had no effect on eradicating healthy saliva-derived biofilm, while free CHX exhibited an inhibitory effect. Furthermore, the 16s rDNA sequencing results showed that p(DH)@CHX had the potential to alter oral microbiota composition and possibly reduce caries risk. In conclusion, the present study presents an alternative option to design an intelligent material to prevent and treat dental caries.

The efficacy of henna (Lawsonia inermis L.) mouthwash versus chlorhexidine gluconate 0.2% mouthwash as adjuvant therapy of oral lichen planus: A randomized double-blind clinical trial.

ETHNOPHARMACOLOGICAL RELEVANCE: In modern medicine, some traditional remedies are introduced to be effective in treatment. Accordingly, the henna plant (Lawsonia inermis L.) is studied more than before. Previous studies have shown many medical properties for henna, such as anti-inflammatory and anti-fungal properties. AIM OF THE STUDY: Oral lichen planus (OLP) is a common mucocutaneous disease with chronic immunomodulatory disruptions. Topical corticosteroids are the first line of OLP treatment. Previous studies have suggested different adjunctive therapies for preventing the side effects of corticosteroids overuse. This study aimed to compare the effects of henna and chlorhexidine mouthwashes as adjunctive therapy. MATERIALS AND METHODS: This parallel-group, double-blind, randomized controlled study was conducted on forty OLP patients. Luteolin content was determined in Henna mouthwash composed of 2% aqueous extract of henna, 2% ethanol, 10% glycerol, and 0.1% methylparaben distilled water. Henna or chlorhexidine mouthwashes were prescribed twice daily as an adjuvant to the topical corticosteroid treatment. Visual analog scale (VAS) index and Thongprasom rating were used to measure pain intensity and clinical signs of patients at days 0,7, and 14. The collected data were analyzed using SPSS software (version 26.0; SPSS). Ordinal logistic regression was used to investigate the effect of independent variables on Thongprasom and VAS scores. RESULTS: In this clinical trial, 82.6% of the participants were women. There was no difference between the two study groups in terms of VAS scores (p = 0.404) and clinical features (p = 0.305) in the second follow-up visit. All drug regimens caused clinical signs and symptoms relief. CONCLUSIONS: There was no significant difference between the groups receiving topical corticosteroid supplementation, neither henna mouthwash nor chlorhexidine mouthwash. The therapeutic effects of henna mouthwash in the main or adjuvant treatment of OLP need more evaluation in future research. Henna mouthwash can be a good alternative to chlorhexidine mouthwash if no side effects are reported.

Effects of Hand Hygiene Using 4% Chlorhexidine Gluconate or Natural Soap During Hand Rubbing Followed by Alcohol-Based 1% Chlorhexidine Gluconate Sanitizer Lotion in the Operating Room.

Objective: Hand hygiene using either 4% chlorhexidine gluconate (CHG) or natural soap during hand rubbing, followed by alcohol-based 1% CHG sanitizer lotion in the operating room was compared to assess bacterial reduction, skin moisture, skin texture, and hand hygiene using qualitative questionnaires. Approach: A crossover study with 36 professional scrub nurses at two medical centers was performed to compare 4% CHG followed by alcohol-based 1% CHG sanitizer lotion, the Two-stage method with handwashing using natural soap followed by alcohol-based 1% CHG sanitizer lotion, and the Waterless method, after a period of 10 days of use. The study completely followed CONSORT, www.consort-statement.org. Results: There was no significant difference in bacterial reduction based on the bacterial colony-forming units between the two methods. The skin moisture and skin roughness scores were not significantly different between the two methods. The Waterless method was significantly better than the Two-stage method regarding "foaming," "quality," "longevity" (p < 0.0001, p < 0.0001, and p < 0.0001, respectively), but "disappearance" was significantly better by the Two-stage method (p = 0.0095) during washing and rubbing. Immediately after washing and rubbing, the Waterless method was significantly better regarding "tightness" and "moisture," whereas the Two-stage method was significantly better regarding "stickiness" (p = 0.0114, p = <0.0001, and 0.0059, respectively) Innovation: The Waterless method using natural soap during handwashing followed by alcohol-based 1% CHG sanitizer lotion was as effective as the Two-stage method of 4% CHG followed by alcohol-based 1% CHG sanitizer lotion. Conclusion: Handwashing using natural soap is simple and superior to hand scrubbing in several aspects.

Pseudomembranous oral candidiasis resolved with a mouthwash containing 0.05% chlorhexidine + 0.05% cetylpyridinium chloride.

A 50-year-old woman was referred to the clinic reporting oral discomfort during the previous month and plaques of a white removable slough. Diagnosis of pseudomembranous oral candidiasis was clinically confirmed. When the tongue and palatal mucosa were wiped with gauze, the soft yellowish-white slough detached revealing the erythematous surface beneath. The patient also presented paranoid schizophrenia and severe depression, pulmonary emphysema, and two vertebral hernias. She was a smoker (10 cigarettes per day) with xerostomia that was being treated with: bupropion, reboxetine, quetiapine, trazadone clotiapine, pregabalin, fentanyl (patches), and alprazolam. To minimize the risk of potential drug interactions, a mouthwash containing 0.05% chlorhexidine + 0.05% cetylpyridinium chloride was prescribed three times a day for two weeks. At the end of the two weeks, the candidiasis had abated.

Regression discontinuity of blood culture contamination rate after changing of disinfectants: retrospective observational study.

Blood cultures are indispensable for detecting life-threatening bacteremia. Little is known about associations between contamination rates and topical disinfectants for blood collection in adults. We sought to determine whether a change in topical disinfectants was associated with the rates of contaminated blood cultures in the emergency department of a single institution. This single-center, retrospective observational study of consecutive patients aged 20 years or older was conducted in the emergency department (ED) of a university hospital in Japan between August 1, 2018 and September 30, 2020. Pairs of blood samples were collected for aerobic and anaerobic culture from the patients in the ED. Physicians selected topical disinfectants according to their personal preference before September 1, 2019; alcohol/chlorhexidine gluconate (ACHX) was mandatory thereafter, unless the patient was allergic to alcohol. Regression discontinuity analysis was used to detect the effect of the mandatory usage of ACHX on rates of contaminated blood cultures. We collected 2141 blood culture samples from 1097 patients and found 164 (7.7%) potentially contaminated blood cultures. Among these, 445 (20.8%) were true bacteremia and 1532 (71.6%) were true negatives. Puncture site disinfection was performed with ACHX for 1345 (62.8%) cases and with povidone-iodine (PVI) for 767 (35.8%) cases. The regression discontinuity analysis showed that mandatory ACHX usage was significantly associated with lower rates of contaminated blood cultures by 9.6% (95% confidence interval (CI): 5.0%-14.2%, P < 0.001). Rates of contaminated blood cultures were significantly lower when ACHX was used as the topical disinfectant.

Reducing surgical site infections in low-income and middle-income countries (FALCON): a pragmatic, multicentre, stratified, randomised controlled trial.

BACKGROUND: Surgical site infection (SSI) is the most common postoperative complication worldwide. WHO guidelines to prevent SSI recommend alcoholic chlorhexidine skin preparation and fascial closure using triclosan-coated sutures, but called for assessment of both interventions in low-resource settings. This study aimed to test both interventions in low-income and middle-income countries. METHODS: FALCON was a 2 × 2 factorial, randomised controlled trial stratified by whether surgery was clean-contaminated, or contaminated or dirty, including patients undergoing abdominal surgery with a skin incision of 5 cm or greater. This trial was undertaken in 54 hospitals in seven countries (Benin, Ghana, India, Mexico, Nigeria, Rwanda, and South Africa). Patients were computer randomised 1:1:1:1 to: (1) 2% alcoholic chlorhexidine and non-coated suture, (2) 2% alcoholic chlorhexidine and triclosan-coated suture, (3) 10% aqueous povidone-iodine and non-coated suture, or (4) 10% aqueous povidone-iodine and triclosan-coated suture. Patients and outcome assessors were masked to intervention allocation. The primary outcome was SSI, reported by trained outcome assessors, and presented using adjusted relative risks and 95% CIs. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, NCT03700749. FINDINGS: Between Dec 10, 2018, and Sept 7, 2020, 5788 patients (3091 in clean-contaminated stratum, 2697 in contaminated or dirty stratum) were randomised (1446 to alcoholic chlorhexidine and non-coated suture, 1446 to alcoholic chlorhexidine and triclosan-coated suture, 1447 to aqueous povidone-iodine and non-coated suture, and 1449 to aqueous povidone-iodine and triclosan-coated suture). 14·0% (810/5788) of patients were children and 66·9% (3873/5788) had emergency surgery. The overall SSI rate was 22·0% (1163/5284; clean-contaminated stratum 15·5% [454/2923], contaminated or dirty stratum 30·0% [709/2361]). For both strata, there was no evidence of a difference in the risk of SSI with alcoholic chlorhexidine versus povidone-iodine (clean-contaminated stratum 15·3% [223/1455] vs 15·7% [231/1468], relative risk 0·97 [95% CI 0·82-1·14]; contaminated or dirty stratum 28·3% [338/1194] vs 31·8% [371/1167], relative risk 0·91 [95% CI 0·81-1·02]), or with triclosan-coated sutures versus non-coated sutures (clean-contaminated stratum 14·7% [215/1459] vs 16·3% [239/1464], relative risk 0·90 [95% CI 0·77-1·06]; contaminated or dirty stratum 29·4% [347/1181] vs 30·7% [362/1180], relative risk 0·98 [95% CI 0·87-1·10]). With both strata combined, there were no differences using alcoholic chlorhexidine or triclosan-coated sutures. INTERPRETATION: This trial did not show benefit from 2% alcoholic chlorhexidine skin preparation compared with povidone-iodine, or with triclosan-coated sutures compared with non-coated sutures, in preventing SSI in clean-contaminated or contaminated or dirty surgical wounds. Both interventions are more expensive than alternatives, and these findings do not support recommendations for routine use. FUNDING: National Institute for Health Research (NIHR) Global Health Research Unit Grant, BD.