Microbial Contamination of Different Toothbrush Types Stored in Bathrooms and Rooms in Adolescents

Participants assigned to this arm used a standard plastic toothbrush (Colgate Extra Clean) twice daily for two minutes using the modified Stillman brushing technique and standardized fluoride toothpaste. After each use, the toothbrush was rinsed under tap water and stored upright and uncovered in the bathroom. The intervention lasted one month, after which the toothbrush was collected for microbiological analysis.

A commercially available standard plastic toothbrush (Colgate Extra Clean, Colgate-Palmolive Company, New York, NY, USA) was used as the active comparator. Participants brushed their teeth twice daily for two minutes using the modified Stillman technique and standardized fluoride toothpaste for one month. After each use, the toothbrush was rinsed under tap water and stored upright and uncovered in the assigned storage environment (bathroom or room outside the bathroom). At the end of the intervention period, toothbrushes were collected for microbiological analysis.

Participants assigned to this arm used a standard plastic toothbrush (Colgate Extra Clean) twice daily for two minutes using the modified Stillman brushing technique and standardized fluoride toothpaste. After each use, the toothbrush was rinsed under tap water and stored upright and uncovered in a room outside the bathroom. The intervention lasted one month, after which the toothbrush was collected for microbiological analysis.

A commercially available standard plastic toothbrush (Colgate Extra Clean, Colgate-Palmolive Company, New York, NY, USA) was used as the active comparator. Participants brushed their teeth twice daily for two minutes using the modified Stillman technique and standardized fluoride toothpaste for one month. After each use, the toothbrush was rinsed under tap water and stored upright and uncovered in the assigned storage environment (bathroom or room outside the bathroom). At the end of the intervention period, toothbrushes were collected for microbiological analysis.

Participants assigned to this arm used a silver nanoparticle-containing toothbrush (Splat Sensitive Silver) twice daily for two minutes using the modified Stillman brushing technique and standardized fluoride toothpaste. After each use, the toothbrush was rinsed under tap water and stored upright and uncovered in the bathroom. The intervention lasted one month, after which the toothbrush was collected for microbiological analysis.

A commercially available silver nanoparticle-containing toothbrush (Splat Sensitive Silver, SPLAT-COSMETICA, Moscow, Russia) was used to evaluate microbial contamination compared with a standard plastic toothbrush. Participants brushed their teeth twice daily for two minutes using the modified Stillman technique and standardized fluoride toothpaste for one month. After each use, the toothbrush was rinsed under tap water and stored upright and uncovered in the assigned storage environment (bathroom or room outside the bathroom). At the end of the intervention period, toothbrushes were collected for microbiological analysis.

Participants assigned to this arm used a silver nanoparticle-containing toothbrush (Splat Sensitive Silver) twice daily for two minutes using the modified Stillman brushing technique and standardized fluoride toothpaste. After each use, the toothbrush was rinsed under tap water and stored upright and uncovered in a room outside the bathroom. The intervention lasted one month, after which the toothbrush was collected for microbiological analysis.

A commercially available silver nanoparticle-containing toothbrush (Splat Sensitive Silver, SPLAT-COSMETICA, Moscow, Russia) was used to evaluate microbial contamination compared with a standard plastic toothbrush. Participants brushed their teeth twice daily for two minutes using the modified Stillman technique and standardized fluoride toothpaste for one month. After each use, the toothbrush was rinsed under tap water and stored upright and uncovered in the assigned storage environment (bathroom or room outside the bathroom). At the end of the intervention period, toothbrushes were collected for microbiological analysis.

Participants assigned to this arm used a bamboo charcoal toothbrush (Colgate Bamboo Charcoal) twice daily for two minutes using the modified Stillman brushing technique and standardized fluoride toothpaste. After each use, the toothbrush was rinsed under tap water and stored upright and uncovered in the bathroom. The intervention lasted one month, after which the toothbrush was collected for microbiological analysis.

A commercially available bamboo charcoal toothbrush (Colgate Bamboo Charcoal, Colgate-Palmolive Company, New York, NY, USA) was used to evaluate microbial contamination compared with a standard plastic toothbrush. Participants brushed their teeth twice daily for two minutes using the modified Stillman technique and standardized fluoride toothpaste for one month. After each use, the toothbrush was rinsed under tap water and stored upright and uncovered in the assigned storage environment (bathroom or room outside the bathroom). At the end of the intervention period, toothbrushes were collected for microbiological analysis.

Participants assigned to this arm used a bamboo charcoal toothbrush (Colgate Bamboo Charcoal) twice daily for two minutes using the modified Stillman brushing technique and standardized fluoride toothpaste. After each use, the toothbrush was rinsed under tap water and stored upright and uncovered in a room outside the bathroom. The intervention lasted one month, after which the toothbrush was collected for microbiological analysis.

A commercially available bamboo charcoal toothbrush (Colgate Bamboo Charcoal, Colgate-Palmolive Company, New York, NY, USA) was used to evaluate microbial contamination compared with a standard plastic toothbrush. Participants brushed their teeth twice daily for two minutes using the modified Stillman technique and standardized fluoride toothpaste for one month. After each use, the toothbrush was rinsed under tap water and stored upright and uncovered in the assigned storage environment (bathroom or room outside the bathroom). At the end of the intervention period, toothbrushes were collected for microbiological analysis.

The presence or absence of Streptococcus mutans on toothbrush bristles was assessed after one month of use. Bristle samples were cultured on selective Mitis Salivarius agar supplemented with bacitracin and potassium tellurite following broth enrichment. Suspected isolates were identified using the VITEK 2 Compact system. The outcome was recorded as a binary variable (detected/not detected), and the proportion of contaminated toothbrushes was compared across toothbrush types and storage environments.

The presence or absence of Lactobacillus spp. on toothbrush bristles was assessed after one month of use. Bristle samples were cultured on Rogosa agar adjusted to pH 5.5 following broth enrichment. Suspected isolates were identified using the VITEK 2 Compact system. The outcome was recorded as a binary variable (detected/not detected), and the proportion of contaminated toothbrushes was compared across toothbrush types and storage environments.

The presence or absence of Candida albicans on toothbrush bristles was assessed after one month of use. Bristle samples were cultured on Sabouraud dextrose agar supplemented with chloramphenicol following broth enrichment. Suspected isolates were identified using the VITEK 2 Compact system. The outcome was recorded as a binary variable (detected/not detected), and the proportion of contaminated toothbrushes was compared across toothbrush types and storage environments.

Dental plaque accumulation was assessed using the Silness and Löe Plaque Index at baseline and after one month of toothbrush use. The change in plaque index was calculated by subtracting the baseline score from the one-month score. Changes were compared across toothbrush types and storage environments. Lower scores indicate less plaque accumulation.

Gingival inflammation was assessed using the Löe and Silness Gingival Index at baseline and after one month of toothbrush use. The change in gingival index was calculated by subtracting the baseline score from the one-month score. Changes were compared across toothbrush types and storage environments. Lower scores indicate less gingival inflammation.

Buccal periodontal probing depth was measured in millimeters using a periodontal probe (Hu-Friedy No. 15) at baseline and after one month of toothbrush use. Measurements were obtained as part of a standardized six-site periodontal examination of all teeth present. The change in buccal probing depth was calculated by subtracting the baseline value from the one-month value. Changes were compared across toothbrush types and storage environments. Positive values indicate an increase in probing depth.

Lingual periodontal probing depth was measured in millimeters using a periodontal probe (Hu-Friedy No. 15) at baseline and after one month of toothbrush use. Measurements were obtained as part of a standardized six-site periodontal examination of all teeth present. The change in lingual probing depth was calculated by subtracting the baseline value from the one-month value. Changes were compared across toothbrush types and storage environments. Positive values indicate an increase in probing depth.

Bleeding on probing (BOP) was assessed at six sites per tooth using a periodontal probe (Hu-Friedy No. 15) at baseline and after one month of toothbrush use. BOP was expressed as the percentage of examined sites exhibiting bleeding. The change in BOP was calculated by subtracting the baseline percentage from the one-month percentage and was expressed in percentage points. Changes were compared across toothbrush types and storage environments. Negative values indicate a reduction in gingival bleeding.