Archives of Medicine and Health Sciences

: 2015  |  Volume : 3  |  Issue : 2  |  Page : 357--358

Importance of prevention of noise production in Dental College

Vagish Kumar Laxman Shanbhag 
 Department of Oral Medicine and Radiology, Yenepoya Dental College and Hospital, Yenepoya Research Centre, Yenepoya University, Mangalore, Karnataka, India

Correspondence Address:
Vagish Kumar Laxman Shanbhag
Department of Oral Medicine and Radiology, Yenepoya Dental College and Hospital, Yenepoya Research Centre, Yenepoya University, Mangalore - 575 018, Karnataka

How to cite this article:
Shanbhag VL. Importance of prevention of noise production in Dental College.Arch Med Health Sci 2015;3:357-358

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Shanbhag VL. Importance of prevention of noise production in Dental College. Arch Med Health Sci [serial online] 2015 [cited 2022 Jul 4 ];3:357-358
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Dental professionals are exposed to high noise levels either in dental colleges and/or private clinic for extended period regularly which is of significant concern. [1],[2],[3] The danger to hearing from the dental-clinic working environment in dental colleges cannot be underestimated. Also the amount of noise exposure the dental specialists receive either prior to their postgraduate specialty training or in their office environment should be considered. [4] Work-related hearing loss continues to be a critical safety and healthcare issue. Hearing loss has adverse impact on quality of life. Indeed, the National Institute of Occupational Safety and Health (NIOSH) included occupational hearing loss in the list of priority areas for research. Occupational Safety and Health Administration (OSHA) has reported the daily permissible noise level of 85 decibels for 8 hours of continual exposure. [1],[3]

The sources of dental sounds that can pose as a potential hazard to hearing system of dentists and patients include high-speed turbine hand pieces; low-speed hand pieces; contra-angle hand piece; two-way syringe; high-velocity suction; ultrasonic instruments and cleaners; vibrators; mixing devices such as amalgamators, stone mixers; polishing and lathe instruments; cutting and vibrating instruments; and model trimmers. [1],[3] Prolonged acoustic noise is harmful and can cause noise-induced hearing loss (NIHL) which intensifies during life. NIHL may be undetected for years since it is estimated that individuals lose about 28% of hearing before becoming aware of this problem. Initial complaints include tinnitus, minimal degree of high frequency sensorineural loss which can be dismissed as a temporary phenomenon or as minimal in degree as to cause no significant alteration in communicative function. [4],[5] Dentists experience high frequency hearing loss at the beginning in the 4000 Hz to 6000 Hz range. Right-handed dentists exhibit greater hearing loss in the left ear. [4] Dental college set-up had been proven in various studies to be noisier than private clinics. [1],[4],[6] Lecturers, students, technicians spending in prosthesis laboratory have risk of loss of hearing over several years of regular noise exposure. [4],[6] In dental laboratories where all work is carried out by several students and technicians simultaneously in a single, medium sized room, higher noise levels are produced. [1],[7]

Clinical set-up and laboratories should have better sound absorbing material walls, sound proof acoustical ceiling, and restricted entry. [1] Acoustic shields, barrier walls, and partial or total enclosures of noise sources should be considered. Designing acoustics of the clinic to allow for filtering or absorbing noises from other sources is important and can include air conditioning and wooden paneling. Loud sounds from air conditioners and office music should be checked and minimized. [5] Newer equipments produce less noise when compared to old ones. [1],[7] High-speed equipments generally produce more noise than low speed instruments. [7] Contact of suction pump tip with mucosa should be avoided as it intensifies the noise. Also high-volume aspirator produces significantly higher noise level than low-volume aspirator. [7] So whenever possible new, low-speed devices and low-volume aspirator should be preferred. Reducing vibration by vibration-absorbing material and the use of silencers for air and gas flow is encouraged. Ultrasonic frequencies can also damage hearing due to the generation of subharmonics and thus hearing should be protected against these frequencies. The dentist should maintain a distance of 35 cm from his eye to the patient's mouth. [8] The instruments must be activated only when they are ready to be used. Better maintenance and regular servicing of equipments is helpful to minimize high noise production. Noise emission levels of new equipments should be assessed when purchasing it. Simultaneous working of more number of equipments and machinery together result in higher noise levels and should be avoided. It is therefore evident that ways and means of reducing the levels of sound in preclinical, clinical, and laboratory areas should be given some thought along with workers' education in order to protect against the harmful effects of noise. [1]

Noise can have both auditory and non-auditory effects. Non-auditory effects include stress reactions with variations in heart rate, blood pressure, respiration, blood glucose, and lipid levels, associated with psychical consequences like annoyance, mental fatigue sleep disturbances, and a reduction in efficiency, decreased learning performance. Degree of risk to individual dentists depends on several factors such as intensity and type of noise, period of exposure each day, total work duration, distance from the source, and individual age and susceptibility. Constant levels of high noise might affect the students, technicians, and teachers in their work efficiency. Noise can induce learned helplessness, increase arousal, alter the choice of task strategy, and decrease attention to the task. [7] The importance of noise reduction in dental learning areas is obvious, especially for teachers and students, as high level of noise exposure is relatively continuous in such settings. NIHL is usually undetected until damage to the inner ear is advanced. There is no treatment for NIHL. A Hearing Conservation Program (HCP) that includes a noise survey, engineering controls, administrative controls, and personal hearing protectors should be instituted. [6],[7] Administrative controls can be implemented by switching the employees in high-noise areas with those in low-noise areas after a certain period of time has elapsed. It could also involve scheduling operating times so as to minimize the number of employees exposed to high noise levels. Custom-made earplugs or earmuffs, cotton saturated in olive oil and squeezed off excess should be used as earplugs to minimize the hazard. Regular audiograms of dental personnel should be taken to check for hearing loss. Patients with hearing aids should remove them and replace with earplugs during noisy dental procedures to protect their residual hearing, though this may hamper communication. [7],[9]

Chronic exposure to loud noise in environment of dental colleges is capable of causing hearing damage to the dentists, teaching professionals, and technicians in a long run. All personnel working in and around noisy environment should be educated well about the hazards of noise and the means of protection from it. Administrative controls, periodic check-up, and servicing of instruments and machines together with audiogram check-up of individuals working should be implemented periodically in dental colleges.


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