[Federal Register Volume 62, Number 13 (Tuesday, January 21, 1997)]
[Rules and Regulations]
[Pages 2900-2903]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-1336]
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DEPARTMENT OF HEALTH AND HUMAN SERVICES
Food and Drug Administration
21 CFR Part 872
[Docket No. 95N-0033]
Dental Devices; Endodontic Dry Heat Sterilizer
AGENCY: Food and Drug Administration, HHS.
ACTION: Final rule.
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SUMMARY: The Food and Drug Administration (FDA) is issuing a final rule
to require the filing of a premarket approval application (PMA) or a
notice of completion of a product development protocol (PDP) for the
endodontic dry heat sterilizer, a medical device. Commercial
distribution of this device must cease, unless a manufacturer or
importer has filed with FDA a PMA or a notice of completion of a PDP
for its version of the endodontic dry heat sterilizer within 90 days of
the effective date of this regulation. This regulation reflects FDA's
exercise of its discretion to require a PMA or notice of completion of
a PDP for the preamendments device.
EFFECTIVE DATE: January 21, 1997.
FOR FURTHER INFORMATION CONTACT: Joseph M. Sheehan, Center for Devices
and Radiological Health (HFZ-215), Food and Drug Administration, 1350
Piccard Dr., Rockville, MD 20850, 301-827-2974.
SUPPLEMENTARY INFORMATION:
I. Background
In the Federal Register of August 12, 1987 (52 FR 30082), FDA
issued a final rule classifying the endodontic dry heat sterilizer
(Sec. 872.6730 (21 CFR 872.6730)) into class III (premarket approval).
Section 872.6730 applies to: (1) Any endodontic dry heat sterilizer
that was in commercial distribution before May 28, 1976, the date of
enactment of the Medical Devices Amendments of 1976 (Pub L. 94-295),
and (2) any device that FDA has found to be substantially equivalent to
the endodontic heat sterilizer and that has been marketed on or after
May 28, 1976.
In the Federal Register of December 30, 1980 (45 FR 86155), FDA
published the recommendation of the Dental Device Classification Panel
(the panel), of the Medical Devices Advisory Committee, an FDA advisory
committee, regarding the classification of the device.
The panel recommended that the device be in class III (premarket
approval) because the device presented an unreasonable risk of illness
or injury. According to the panel, the devices failed to sterilize
adequately various endodontic and dental instruments. The panel felt
that the failures could be the result of: (1) The device not reaching
and maintaining an adequate temperature because of a faulty thermostat
or (2) the result of unequal heat distribution by the glass beads
throughout the well despite sufficient heat. The panel believed that it
was not possible to establish an adequate performance standard for the
device because satisfactory performance had never been demonstrated.
The panel recommended the device to be subject to premarket approval to
ensure that manufacturers of the device demonstrate satisfactory
performance and that further study was necessary to determine the
causes of the device's ineffectiveness.
FDA agreed with the panel's recommendation that endodontic dry heat
sterilizers be classified into class III. FDA believed that there was
an unreasonable risk of illness or injury because of the potential
failure of the device to sterilize dental instruments adequately. FDA
believed that there was inadequate information to determine if general
controls or a performance standard would provide reasonable assurance
of safety and effectiveness.
In the Federal Register of June 7, 1995 (60 FR 30032), FDA
published a proposed rule to require the filing under section 515(b) of
the Federal Food, Drug, and Cosmetic Act (the act) (21 U.S.C. 360e(b))
of a PMA or a notice of completion of a PDP for the endodontic dry heat
sterilizer. In accordance with section 515(b)(2)(A) of the act, FDA
included in the preamble to the proposal the agency's proposed findings
with respect to the degree of risk of illness or injury designed to be
eliminated or reduced by requiring the device to meet the premarket
approval requirements of the act, and the benefits to the public from
use of the device (60 FR 30032 at 30037). The June 7, 1995, proposed
rule also provided an opportunity for interested persons to submit
comments on the proposed rule and the agency's findings. Under section
515(b)(2)(B) of the act, FDA also provided an opportunity for
interested persons to request a change in the classification of the
device based on new information relevant to its classification. Any
petition requesting a change in classification of the endodontic heat
sterilizer was required to be submitted by September 5, 1995. The
comment period closed August 7, 1995.
[[Page 2901]]
FDA received one comment in response to the proposed rule. The
comment recommended that the endodontic dry heat sterilizer remain
classified as class III, until sufficient evidence has been submitted
documenting the safety and efficacy of these devices. It also pointed
out concern in the use of the endodontic dry heat sterilizer for the
generalized sterilization of instruments because of marked temperature
gradients within the well which could result in inadequate
sterilization and the appropriate use of the devices to sterilize large
bulk instruments. FDA agrees with the concern and the comment that a
PMA be required for endodontic dry heat sterilizers.
II. Findings With Respect to Risks and Benefits
A. Degree of Risk
The primary risk to health is infection through the use of
inadequately sterilized instruments. A review of the literature has
identified the following problems associated with the use of endodontic
dry heat sterilizers which can contribute to the inability of these
devices to sterilize instruments, including general medical
instruments.
1. Temperature Variations Within the Well.
There are many reports in the literature describing the temperature
variations found within the wells of endodontic dry heat (glass bead)
sterilizers. It has been reported that the temperature distribution in
four brands of these devices at two different sites from the center and
at six different depths in the well varied significantly depending upon
location. The temperature was highest at a location which was closest
to the wall and midway down from the surface. Furthermore data have
demonstrated temperature variations as much as 10 deg.C over time near
the periphery of the well. The information in the literature suggested
that endodontic dry heat (glass bead) sterilizers should not be used as
a substitute for dry heat convection or steam sterilization sterilizers
because of the temperature variations.
2. Exposure Times for the Sterilization of Instruments.
The manufacturers' recommended exposure times for sterilization of
instruments vary from as short as 2 seconds to 45 seconds for
sterilizers whose purported operating temperatures were from 218 to 260
deg.C. However, location in the well, size and mass, number and shape
of the instruments must be factored into the amount of time required
for sterilization. Larger instruments composed of more metal take more
time to heat than smaller instruments. It was reported that the time
required to raise an instrument's temperature was dependent upon its
size. Small instruments such as root canal files heated rapidly while
large instruments such as cotton pliers never reached the specified
operating temperature. Endodontic dry heat (glass bead) sterilizers
have been reported to be effective only with small instruments that can
be imbedded into the heat transfer media and that their effectiveness
has not been demonstrated for instruments of larger bulk. The insertion
of large instruments would reduce the temperature of the glass beads
below the minimum temperature required for sterilization. Heat
conduction in a large, partially imbedded device would be variable.
Precleaning of the instruments before insertion into the heat
transfer medium in the well of the sterilizer is critical to the
effectiveness of the device. It was reported that if endodontic
instruments were contaminated with a protein load (blood), the time
required for sterilization was more than doubled. Such adverse
conditions can easily be found in infected or gangrenous pulp. There
are reports that spores, which are more resistant to sterilization
processes than vegetative organisms, have been found in the oral cavity
and cultured from pulp material.
3. Lack of Methods to Monitor the Performance/Sterilization Efficacy of
the Device.
There are no identified methods for the routine monitoring of the
sterilization efficacy of the endodontic dry heat sterilizer such as
the ones which exist with the traditional sterilization methods, i.e.,
steam autoclaves, hot air dry heat sterilizers, or ethylene oxide
sterilizers. Chemical and biological indicators are available for
routine monitoring of the efficacy of the cycle parameters and for the
validation of the process specifications for these traditional
sterilizers. The data in the literature, as noted above, suggest that
the user can not be assured that instruments inserted into an
endodontic dry heat sterilizer will be reliably exposed to the minimum
cycle parameters required for sterilization, i.e., exposure of the
device to the set temperature for the specified time.
4. Warm-up Times for Endodontic Dry Heat (Glass Bead) Sterilizers.
Reported warm-up times for these devices range from 15 minutes to
50 minutes with the average of 15-20 minutes. However, it has been
reported that it took up to 30 minutes for the temperature of the glass
beads to stabilize even though the manufacturer claimed that the device
reached operating temperature within 10 minutes.
5. Maintenance of Sterility After Removal From the Device.
The instructions for use for most of the devices do not instruct
the user on the proper procedure to remove instruments from the device
and how to maintain sterility of the instruments or the processed
portion of the instrument during the cool down period. Because of the
temperature variations reported within the wells, there exists the
possibility that heat resistant microorganisms could survive on the
glass beads in the cooler regions near the top of the glass beads and
contaminate the instruments as they are removed from the well. Since
endodontic dry heat sterilizers only process that portion of the
instrument which has been inserted into the glass beads, there is also
the potential of contaminating a sterile field with a device which had
not been properly processed.
6. Heat Transfer Medium Remaining Upon the Devices.
Occasionally the heat transfer medium has been observed to adhere
to wet instruments. If the particles are not detected before the
devices are inserted into the site, then they could cause blockage of
the wound site. This would cause significant problems if the heat
transfer media were glass beads or molten metal.
B. Benefit of the Device
The endodontic dry heat sterilizer is used to decontaminate
endodontic instruments during a procedure on a single patient provided
the instruments are properly cleaned to remove organic debris before
insertion into the unit. In theory the number of microorganisms that
would be introduced into the same site or into a new site on the same
patient during a single procedure would be reduced. Once the procedure
is over, the instruments should be processed using traditional methods
of decontamination and sterilization before use in the next patient.
[[Page 2902]]
C. Discussion of Risks and Benefits
The data in the literature indicate a lack of uniform sterilization
parameters among the various endodontic dry heat (glass bead)
sterilizers which have been marketed. Because of the temperature
variations found within the wells of glass bead sterilizers, exposure
of an instrument to an adequate sterilizing temperature is difficult to
determine and must be confirmed independently for each instrument. Also
determination of the sterilization exposure time is dependent upon
instrument size and mass. It has been reported that some instruments
never reach the appropriate temperature because of their size and mass;
and that endodontic dry heat sterilizers are not appropriate for large
bulk instruments.
Review of the claims being made for these devices suggests that
manufacturers are expanding the claims beyond those originally defined
in Sec. 872.6730. The claims have been expanded to include the
sterilization of general medical instruments and electrolysis and
acupuncture needles, and to devices not regulated by FDA such as
manicurist's instruments. The claims imply that these devices can be
used as a substitute for the traditional methods of sterilization. It
has been noted in the literature that endodontic dry heat sterilizers
are not sterilizers, but are decontaminating devices and that they
should not be used to sterilize instruments between patients. No system
exists for: (1) Monitoring the exposure of the instrument to
sterilization conditions or (2) demonstrating that the sterilization
exposure parameters have been achieved within the well. Only the
portion of the instrument which is inserted into the heat transfer
medium has the potential of being sterilized; the portion which is not
inserted into the glass beads is not sterilized. The use of endodontic
dry heat sterilizers with general medical instruments and with the
implication as a substitute sterilization method raises serious safety
and efficacy questions which the manufacturers of these devices have
not adequately addressed. There is the serious risk of infection
through the use of inadequately processed instruments.
III. Final Rule
Under section 515(b)(3) of the act, FDA is adopting the findings as
published in the preamble to the proposed rule and is issuing this
final rule to require premarket approval of the generic type of device,
endodontic dry heat device, by revising Sec. 872.6730(c).
Under the final rule, a PMA or a notice of completion of a PDP is
required to be filed with FDA within 90 days of the effective date of
this regulation for any endodontic dry heat sterilizer device that was
in commercial distribution before May 28, 1976, or any device that FDA
has found to be substantially equivalent to such a device on or before
September 5, 1995. An approved PMA or declared completed PDP is
required to be in effect for any such device on or before 180 days
after FDA files the application. Any other endodontic dry heat
sterilizer device that was not in commercial distribution before May
28, 1976, or that FDA has not found, on or before September 5, 1995, to
be substantially equivalent to an endodontic dry heat sterilizer device
that was in commercial distribution before May 28, 1976, is required to
have an approved PMA or declared completed PDP in effect before it may
be marketed.
If a PMA or notice of completion of a PDP for an endodontic dry
heat sterilizer device is not filed on or before September 5, 1995,
that device will be deemed adulterated under section 501(f)(1)(A) of
the act (21 U.S.C. 351(f)(1)(A)), and commercial distribution of the
device will be required to cease immediately. The device may, however,
be distributed for investigational use, if the requirements of the
investigational device exemption (IDE) regulations part 812 (21 CFR
part 812) are met.
Under Sec. 812.2(d) of the IDE regulations, FDA hereby stipulates
that the exemptions from the IDE requirements in Sec. 812.2(c)(1) and
(c)(2) will no longer apply to clinical investigations of the
endodontic dry heat sterilizer devices. Further, FDA concludes that
investigational endodontic dry heat sterilizer devices are significant
risk devices as defined in Sec. 812.3(m) and advises that as of the
effective date of the regulations in Sec. 872.6730(c), requirements of
the IDE regulations regarding significant risk devices will apply to
any clinical investigation of an endodontic dry heat sterilizer device.
For any endodontic dry heat sterilizer device that is not subject to a
timely filed PMA or notice of completion of a PDP, an IDE must be in
effect under Sec. 812.20 on or before September 5, 1995, or
distribution of the device for investigational purposes must cease. FDA
advises all persons currently sponsoring a clinical investigation
involving an endodontic dry heat sterilizer to submit an IDE
application to FDA no later than August 7, 1995, to avoid the
interruption of ongoing investigations.
IV. Environmental Impact
The agency has determined under 21 CFR 25.24(a)(8) and (e)(4) that
this action is of a type that does not individually or cumulatively
have a significant effect on the human environment. Therefore, neither
an environmental assessment nor an environmental impact statement is
required.
V. Analysis of Impacts
FDA has examined the impacts of the final rule under Executive
Order 12866 and the Regulatory Flexibility Act (Pub. L. 96-354).
Executive Order 12866 directs agencies to assess all costs and benefits
of available regulatory alternatives and, when regulation is necessary,
to select regulatory approaches that maximize net benefits (including
potential economic, environmental, public health and safety, and other
advantages; distributive impacts; and equity). The agency believes that
this final rule is consistent with the regulatory philosophy and
principles identified in the Executive Order. In addition, the final
rule is not a significant regulatory action as defined by the Executive
Order and so is not subject to review under the Executive Order.
The Regulatory Flexibility Act requires agencies to analyze
regulatory options that would minimize any significant impact of a rule
on small entities. Because for more than 10 years the manufacturers of
these devices have been aware of the need to prepare PMA's for these
devices, the agency certifies that the final rule will not have a
significant economic impact on a substantial number of small entities.
Therefore, under the Regulatory Flexibility Act, no further analysis is
required.
List of Subjects in 21 CFR 872
Medical devices.
Therefore, under the Federal Food, Drug, and Cosmetic Act and under
authority delegated to the Commissioner of Food and Drugs, 21 CFR part
872 is amended as follows:
PART 872--DENTAL DEVICES
1. The authority citation for 21 CFR part 872 continues to read as
follows:
Authority: Secs. 501, 510, 513, 515, 520, 701 of the Federal
Food, Drug, and Cosmetic Act (21 U.S.C. 351, 360, 360c, 360e, 360j,
371).
2. Section 872.6730 is amended by revising paragraph (c) to read as
follows:
Sec. 872.6730 Endodontic dry heat sterilizer.
* * * * *
[[Page 2903]]
(c) Date premarket approval application (PMA) or notice of
completion of product development protocol (PDP) is required. A PMA or
notice of completion of a PDP is required to be filed with the Food and
Drug Administration on or before September 5, 1995, for any endodontic
dry heat sterilizer that was in commercial distribution before May 28,
1976, or that has on or before September 5, 1995, been found to be
substantially equivalent to the endodontic dry heat sterilizer that was
in commercial distribution before May 28, 1976. Any other endodontic
dry heat sterilizer shall have an approved PMA or declared completed
PDP in effect before being placed in commercial distribution.
Dated:September 18, 1996.
Joseph A. Levitt,
Deputy Director for Regulations Policy, Center for Devices and
Radiological Health.
[FR Doc. 97-1336 Filed 1-17-97; 8:45 am]
BILLING CODE 4160-01-F
