Current status of disinfection of dental impressions in Indian dental colleges: a cause of concern

Knowledge and practices about sterilization and disinfection

Aims

The aim of the present study was to evaluate the knowledge and practices employed for infection control in dental laboratories.

Materials and Methods

A preformed questionnaire comprised of 16 questions related to infection control measures was prepared. This questionnaire based survey was then conducted among dental technicians of 60 dental colleges in East India. Data were then recorded and analyzed.

Results

Majority of impressions/prosthesis were carried in plastic bags (93.8%) by laboratory attendants to the laboratory. The responses revealed that majority of impressions were received after wearing gloves (54.6%) from dental attendant. Majority of dental technicians (78.1%) admitted in their responses that they are not aware of infection control measures taken in dental laboratory. Only 32.8% technicians were found to practice disinfection procedure after receiving impression/prosthesis in laboratory from dental operatory. Among protective wears, 70.3%, 95.3%, 32.8%, and 92.2% technicians were found to use gloves, Apron, eye shield, and face mask, respectively. Among all respondents, 59.3% were found to be vaccinated for hepatitis B vaccine.

Conclusion

There is lack of knowledge and motivation among dental technician to practice infection control measures in dental laboratories of dental institutes in North India.

Comparative Evaluation of the Effect of Chemical Disinfectants and Ultraviolet Disinfection on Dimensional Stability of the Polyvinyl Siloxane Impressions

Context

Infection control is an important concept in the present day practice of dentistry. Disinfection of dental impressions is part of the daily routine in a dental clinics. After disinfection, it is important that impressions remain dimensionally stable.

Aim

The purpose of this study was to compare the effect of chemical disinfectants and ultraviolet (UV) disinfection on the dimensional stability of the polyvinyl siloxane impressions.

Objectives

The objective of the study is (1) To evaluate the effect of chemical disinfectant (2% glutaraldehyde and 1% sodium hypochlorite) and UV disinfectant on the dimensional stability of polyvinyl siloxane impression material. (2) Comparative evaluation of the dimensional discrepancy between the cast poured from the polyvinyl impressions material, that is subjected to chemical disinfectant and UV disinfectant to that of cast poured from impressions that were nondisinfected.

Materials and Methods

A customized tray was fabricated to make impressions. Impressions were divided into four groups, 10 samples were disinfected with 2% glutaraldehyde for 20 min, 10 samples were disinfected with 1% sodium hypochlorite for 20 min, 10 samples were disinfected with UV light for 20 min, and 10 samples were not subjected to disinfection which served as control group. All the samples were poured after 30 min in die stone. Measurements were recorded using traveling microscope of 0.001 accuracy. Statistical analysis used in this study was the one-way ANOVA test.

Results

The result showed significant dimensional changes in samples disinfected with 2% glutaraldehyde and 1% sodium hypochlorite, whereas samples disinfected with UV disinfectant unit showed no significant dimensional changes when compared with control group samples. Within the chemical groups, impressions disinfected with 1% sodium hypochlorite showed more discrepancy in the dimensions when compared to the 2% glutaraldehyde disinfected group.

Conclusions

UV light disinfectant can be safely used to disinfect impressions as compared to chemical disinfectants in clinical prosthodontic procedures.

Infection control knowledge and practice: A cross-sectional survey on dental laboratories in dental institutes of North India

Aim and Objectives

The aim of the study was to assess the knowledge of dental laboratory technicians regarding infection control and modes of infection control employed by them.

Settings and Design

A self-assessment questionnaire-based survey was carried out among dental technicians to assess the knowledge and practice of infection control in dental laboratories.

Materials and Methods

Survey instrument containing 16 questions were randomly distributed to 70 dental colleges of North India regarding knowledge of infection control methods and infection control practised in laboratories. Data were collected and analyzed.

Results

The response showed that 30.76% of dental technicians receive 30-50 or more than 50 impressions in a week. About 96.15% of the technicians used a plastic bag to carry impressions. Twenty-five percent of the dental technicians were aware of infection control protocol. Fifty-five percent of the technicians received impressions while wearing gloves and 61.53% of the institutes had a separate receiving area. Nearly 71.15% of the technicians communicate with the doctor regarding the disinfection of impression received in the laboratory. Almost 30.76% of the dental technicians disinfect all the impressions and 67.30% technicians use immersion for disinfection of impressions. Only 38.46% responded that they immerse impressions for 10 min for disinfection. About 73.07% use gloves, 90.38% use mouth masks, 57.69% wear eye shields, and 88.46% wear aprons while working. Nearly 78.84% of the technicians received vaccination against hepatitis B virus. Almost 69.23% of the technicians change pumice slurry after regular intervals, and 75% do not add any disinfectant. Nearly 59.61% of technicians disinfect the prostheses before sending it to the clinic, and 42.30% disinfect them by immersion technique. About disposal of waste, 80.76% said that they dispose the waste properly.

Conclusion

To summarize, most of the technicians were not aware of basic infection control protocols.