Endodontics can be one of the most satisfying aspects of dental practice, provided it is performed in a well-managed working environment. Consideration should be given to specific organizational requirements, which affect the operator, the staff, the patient and, ultimately, the tooth to be treated. The practice of endodontics has become very gadget-oriented and may demand a vast array of small instruments and equipment, depending upon the operator’s preferences, as well as large adjunctive equipment, such as the operation microscope and X-ray machine. Nurses may grow to abhor endodontic cases if they are not fully engaged or involved in the management of the patient. Nurses may also find preparation for an endodontic case laborious in comparison to other procedures. The growth of specialized equipment and materials for various disciplines has enormously complicated the management of ergonomic practice. Endodontic procedures also rate highly on the list of medico-legal challenges posed to defence organizations. It is well to consider, systematically and thoroughly, the clinical operatory, nurse support, operator and medico-legal aspects, patient and finally, the tooth.
The clinical area, office or “operatory”, benefits from having a fresh, bright, warm and welcoming atmosphere. The design, layout and décor help contribute a great deal to enhance its image and comfort for the patient. An environment designed and constructed to allow staff to work efficiently, with comfort and ease, will decrease stress, encourage smooth, relaxed working days, and increase job satisfaction. The operatory should be designed in an uncluttered fashion to facilitate unhindered movement to and from the working area. The image (Fig. 6.1) shows a sub-optimally designed operatory with poor space and access.
The organization of endodontic equipment requires careful thought and should be planned to satisfy the needs of the operator’s working methods and nursing support. Dental equipment companies are increasingly aware of the rapidly changing needs and will help facilitate redesign to meet modern requirements. Thought should be given to the frequency and sequence of use of equipment and materials on a procedure basis, followed by the ergonomic manner in which the procedure could be delivered. This will have implications for how the equipment is laid out within easy reach and where the responsibility lies for smooth delivery in sequential fashion. Engineers have even given thought to the design of a computer controlled dispensing machine that delivers the correct endodontic tool in timely and ordered fashion.
In traditional surgeries, cabinetry and cupboards in an L- or U-shaped configuration should be placed within the working area of both operator and assistant. Work can often be simplified by considering the most useful positions to place the more commonly used instruments. The key element here is the basic space within which this is fitted. Figure 6.1 shows an operatory that could potentially be effective but is severely compromised by lack of sufficient space.
The distance traversed by hand instruments during operative procedures should be minimized; the use of a mobile cabinet or cervical tray (Fig. 6.2) may help achieve this. A mobile cabinet provides flexibility with a worktop area and drawers, which may be sited close to the patient. Simple cervical trays without hand-piece and 3-in-1 cord fittings will also allow instruments to be approximated to the tooth being treated.
Customized carts have been favoured among endodontists since they provide easy and ergonomic access to a range of hand-pieces, including air-rotors, slow speed motors, reducing speed/controlled torque handpieces, ultrasonic or sonic instruments, irrigation devices and obturation devices (Fig. 6.3). Some believe that the development of cordless devices may obviate the need for cart or mobile systems. However, given the pace of change in equipment and material available demands flexibility and it seems the best way to achieve this is not to have fixed worktops but mobile, multilayered systems providing an increased area within easy reach (Fig. 6.4). The mobile systems may be stored away in a separate area where they can be replenished and be ready for use in any surgery. The trend may be toward having separate mobile units for different speciality or procedure work. Such a system should also be complemented by an effective restocking system that prioritizes the most frequently used items. Finally, the system should be adaptable enough to allow immediate and easy integration of new equipment and materials, which appear on the market annually, without disrupting the previous system.
Thought should be given to rapid turnaround between patients, so that disinfection can be facilitated and the new set-up delivered by exchange of a mobile unit. Flow and space should be streamlined so that used equipment is directly transferred for washing and disinfection.
The work surfaces of dental units and cupboards are readily contaminated by aerosol from the use of hand-pieces, triple syringe sprays and ultrasonic instruments, and therefore, selected surfaces should be easy to maintain clean. The junction between the work surface and the wall should cove to aid cleaning. Any joints on the work surface should be sealed to prevent accumulation of contaminated matter and allow cleaning.
Surfaces liable to become contaminated with body fluids or infected matter should be identified and designated high contamination zones. These areas benefit from impervious disposable coverings that can be changed and the surface beneath cleaned between patients. All disposable and sterilizable instruments and trays fall within this area (Fig. 6.5).
Low contamination zones include all other areas that, during normal clinical procedures, are not expected to become coated with infected material. In these areas, procedures should be adopted to limit the number of surfaces touched each time a patient is treated. The operator should be aware that their hands are generally contaminated and hand-washing techniques have gained a high priority in helping to eliminate serious infection spread in hospitals. Figure 6.6 shows bacterial growth on agar plates from hand prints before and after hand washing using Hibiscrub hand cleanser.
All waterlines and airlines should be fitted with antiretraction valves to help prevent contamination of the lines. Water retraction valves may aspirate infected material back into the tubing. Hand-pieces with water sprays should be allowed to discharge water into the sink for 20–30 seconds after each patient. Overnight microbial accumulation can be reduced if the hand-piece is run for two minutes at the beginning of each day. Many units now have a bottled water system, disinfectants advised by the manufacturer may be run through the system at the end of each day to reduce the microbial load and prevent the build-up of biofilm. Specific agents, such as Alpron (Fig. 6.7) are now available to eradicate biofilms in dental unit water lines (Fig. 6.8).
Fig. 6.7 Dental unit waterline decontaminant – Alpron solution (Quality Water Specialists Ltd, Yorkshire) containing citric acid, sodium-p-toluolsulphonechloramide <0.2%, EDTA and sodium tosylchloramide
A very wide range of instruments designed specifically for endodontic treatment is available. Some of these instruments have been used for many years; others are new and, in some cases, highly technical. The instruments described in this book are readily available and commonly used, while a range of customized instruments named by their inventors or modifiers are also available.
Use of the front surface mirror overcomes the problems associated with double images, which are produced when the reflecting surface is beneath a layer of glass. The endodontic locking tweezers allow small items to be gripped safely and transferred between assistant and operator (Fig. 6.10). They are particularly useful when handling gutta-percha points, paper points and cotton-wool pledgets. The tips of the beaks should be blunt and grooved. A Mitchell’s trimmer may be used to remove cement and either temporary or permanent crowns. The canal probe or DG 16 should be long, fine, sharp and strong. It is used to feel the floor of the pulp chamber when locating canal orifices. A Briault probe is used to feel for overhangs when removing the roof of the pulp chamber and to check the internal margins of any restorations. Two other probes, although not included in the basic kit, are useful in periodontal assessment: the explorer EXD3CH (Fig. 6.11) (used to examine restorations, such as bridges), furcation probe with markings (for measuring the extent of periodontal furcation involvement in posterior teeth); and a pocket measuring probe with a fine shank, blunt end, and millimetre markings (as illustrated in Chapter 11). Long-shanked excavators (Fig. 6.12) come in a range of designs to allow access to the pulp chamber. These are used for scooping out the remains of the pulp and excess gutta-percha; also for flicking away pulp stones. The flat plastic assists in placement of inter-appointment provisional restorations. The ruler is used to measure and set instrument lengths. The nurse can provide initial measurement but the operator may wish to use a finger-ring held ruler for checking or fine adjustments.
There are many brands of Dental Operating Microscopes available on the market. They vary by the optical system; a continuous zoom versus series of steps of magnification (3.4×, 5.1×, 8.5×, 13.6×, 21.3×); fixed versus inclinable binoculars; halogen, Xenon or LED illumination; and manual versus foot pedal for hands-free operation. Installation of video camera and monitor or assistant scope could facilitate four-handed endodontic practice. The former set-up would allow the dental assistant to carry out other tasks and for documentation purposes. The type of microscope and installation (ceiling mounts, wall mounts, floor-stands, custom-mounts) may be limited by the size of the dental surgery and the quality of the ceiling and walls. An optimal mounting arrangement would facilitate easy access and positioning, as well as make best use of the available surgery space (Fig. 6.13).
All medical devices, including X-ray machines, purchased for use in countries within the European Union should have acquired CE (stands for Communauté Européenne, i.e. European Community) marking according to the Medical Devices Regulations 2002. The wiring must comply with BS 7671: 2008, 17th edition. Each newly installed X-ray machine must receive a Critical Examination (IRR99 reg 31) by the installer confirming the correct function of safety systems, leakage exposure rates and in-beam dose. An acceptance test must be performed prior to clinical use and, thereafter, routine tests at suitable intervals.
Current dental X-ray machines are normally microprocessor-controlled digital devices with touch contact keyboards to set the exposure time and area to be exposed. The tube voltage of most current machines is 70 kV and must comply with a suitable British or international standard for construction. Most current machines are suitable to be used with conventional and digital radiographic techniques.
Dental X-ray machines come in a variety of configurations including mobile units or wall, floor column or dental unit mounted machines. Recently, a number of cordless hand-held dental X-ray machines with high-frequency, 60 kV DC X-ray generator have become available (Fig. 6.14). The advantages of these hand-held units include flexibility in positioning, spacing saving and economy as a single device can serve multiple surgeries. However, the X-ray tube, X-ray control circuitry, and high voltage generator (transformer) contained in a single, lead shielded housing may increase the risk of operator exposure to radiation as a result of tube leakage and radiation back scatter. The back scatter can be reduced by a properly deployed lead acrylic disc surrounding the exposure aperture cylinder to absorb and limit this unnecessary dose. A theoretical increase in patient dose from these units could result from repeated exposure required due to operator/patient movement.
Each employer is responsible for ensuring that all Practitioners, Referrers and Operators are suitably trained. Normally, a practice should appoint a Radiation Protection Supervisor. Persons responsible for exposing X rays should be suitably trained, a record of current training should be recorded and regular refresher training scheduled and audited by the employer.
It is important to use some form of magnification during non-surgical retreatment – if you can see it, you can probably do it, for example removing a trough of dentine around a post or fractured instrument requires good magnification, good lighting, and a steady hand. Longer appointments are required for retreatment cases, in particular for removal of foreign material from root canals. Ultrasonic units and tips (Fig. 6.16) are very useful equipment for cutting a trough around embedded metallic material. There is equipment specifically designed for removal of coronal cast restorations (Fig. 6.17), posts (Fig. 6.18), fractured instruments (Figs 6.19, 6.20) and for repair of strip perforation.
Fig. 6.19 (a) Steiglitz and (b) endodontic fine-beaked forceps, (c) instrument removal system (IRS), (d) Cancellier tubes and cyanoacrylate glue, (e) ultradent tubes as an alternative to Cancellier tubes
All instruments contaminated with oral and other body fluids should be cleaned and sterilized after use. There are three stages to the sterilization process: presterilization cleaning; sterilization; and storage. The surgery should be designed to facilitate a dirty-to-clean workflow to prevent recontamination of decontaminated instruments. An example layout (Fig. 6.29) for essential quality requirements for setting up a decontamination area is given by the Health Technical Memorandum 01-05: Decontamination in primary care dental practices. Dentists should note the manufacturers’ instructions and ensure these are followed. There is a progressive move towards using instruments once only. Many nickel–titanium rotary instruments have a sign on the packet showing a number 2 with a diagonal line running through it, which means for one use only (Fig. 6.30). It should be noted that />