12/98 CDA Journal - Digital Tools for Clinical Dentistry

1998 JOURNAL OF THE CALIFORNIA DENTAL ASSOCIATION

Digital Tools for Clinical Dentistry — An Internet Tutorial

Jack D. Preston, DDS

Copyright 1998 Journal of the California Dental Association.

Computer technology has expanded the scope of digital tools that play a significant role in the practice of dentistry. In the search for current information and references about these devices, the Internet has become an essential resource. This paper will deal with some of the available digital adjuncts and their useful application in the clinical practice of dentistry, and will point the reader to web sites that are pertinent and informative.

For many years dentistry has evolved through a series of changes that have been progressive but not dramatic. Exceptions to this have included the advent of the high-speed dental handpiece, dental implants, and the necessity for barrier protection. The advent of the age of computing did little to alter this evolution, even though many dentists began to use computers for bookkeeping and office management. However, it appears that computer-based devices are now beginning to play a more significant role in the practice of dentistry, and this role will be expanded. As computerization of the dental practice spreads from the front office into the operatories, components are more easily added and, once the first implementation is accomplished, each addition becomes easier. Integrating all the components into a networked system is often a challenge, but is essential for a fully automated dental office.

The increased computing speed and storage capacity of modern computers exceeds dentistry's demands. The storage requirements of images -- either radiographs or camera images -- mandate significant storage capacity. The easy availability of large hard drives (nine and 18 gigabytes), external and internal alternative media (such as Jaz or Zip drives), and writeable and rewriteable CD ROMs have all facilitated image storage. The size of image files mandates large storage capacity devices as well as rapid processing speeds.

With so many different products being offered to the profession, it is difficult to sort through all the conflicting advertising claims. Textbooks and periodicals cannot be published rapidly enough to accurately review current technology. The World Wide Web has become an essential reference for the electronics shopper. Before buying any product, the interested purchaser has the opportunity to use the rich facilities of the Internet to both review the various products and gather valuable scientific information about the technology. This paper will deal with some of the available digital adjuncts and their useful application in the clinical practice of dentistry, and will point the reader to web sites that are pertinent and informative. Primary consideration will be given to five devices: digital radiography, intraoral cameras, CAD/CAM, computer color matching and periodontal devices.

Digital Radiography Systems

Since its advent in the United States several years ago with the introduction of the Trophy® system, digital radiography has yet to fulfill the predictions originally made for it. Although it is difficult to accurately gather data, it is said that approximately 5 percent of the dentists in the United States use digital radiography. That percentage is higher in Europe. Approximately 6,000 digital x-ray systems have been sold in Europe in 1996, where the market is growing at a 35 percent annual rate.¹

Fig 1. The CCD of an intaroral camera is located behind the lens.
Digital radiography, also called computed radiography, is available in many forms, from the simple digitization of film using scanners or videography to the most complex and expensive computer-assisted tomography (CAT scan). The most common dental application of computed radiography involves the use of a sensor instead of typical x-ray film. This sensor is usually a charge-coupled device (CCD). Bell Laboratories invented CCDs in 1970.² Since that time, the CCD has revolutionized video recorders, cameras and other devices. Without delving deeply into the physics of this system, suffice it to say that the CCD is a type of silicon semiconductor that stores and transfers electrons. A phosphor screen photoelectrically generates electrons that are captured in wells and sequentially transferred and read out electronically. These microscopic elements of photosensitive material are comparable in size to those on radiographic film. Nearly all electronic cameras also use CCD technology (Figure 1) and there is a broad range of sizes and qualities of CCD sensors. Pertinent technical information for those wishing to gain a better understanding of CCD technology can be found on the Internet at:

www.suni.com/pages/lasrfoc.htm, and
www.suni.com/pages/laserf.htm.^3,4

The CCD digital radiography sensor is typically composed of four elements: a sealed casing, a phosphor screen, a fiberoptic conductor, and the CCD itself. The fiberoptic conductor originally was tapered to allow a larger sensing area to be conducted to a smaller CCD. Current systems have larger CCDs that prevent the need for tapering. The phosphor screen converts x-ray energy to light energy, photons, that are conducted by the fiberoptic unit to the sensor. The quantity of the photon energy is directly related to the amount of x-ray energy, and the number of electrons deposited in the well of the CCD is likewise directly related to the source energy. Each electron well represents a point of information, just as do the silver crystals of traditional film. The semiconductor wells, however, are precisely ordered while the silver crystals of film are irregular and random. The number of electrons deposited is proportional to the strength of the stimulus. The semiconductor wells are then sequentially emptied in bucket brigade fashion, and reconstructed into a signal that equates to the relative penetration of the target by the x-ray beam. This signal provides information for the positioning and relative gray levels of the pixels on a display screen (monitor). Because the image is composed of varying gray levels represented by the number of electrons in a given well, it is important not to overexpose a CCD sensor. Unlike film where increased radiation may result in a better image, an overfilled CCD results in a much poorer image. It is better to slightly underexpose the image, and then compensate by manipulating the brightness and contrast using the software tools.

Diagnostic Accuracy

The primary criterion that digital radiography must meet is diagnostic accuracy. Dental x-ray film is still the standard against which a computed radiography must be measured. Several factors contribute to the diagnostic accuracy of a digital radiograph. These include dynamic range, resolution, and signal-to-noise ratio. Dynamic range relates to the relative blackness of blacks, whiteness of whites, and definition of the gray tones in between.

Fig 2. Lesions were sijmulated in these four exracted teeth. Round burs from No. 1/2 to No. 4 were used. The burs were embedded to varying depths and some surfaces were left unaltered.
High dynamic range is desirable. Spatial resolution relates to the size of the smallest observable details. It is often measured using a line pair phantom5 or by phantom devices using calibrated radiolucent or radiopaque elements (Figure 2). A greater number of line pairs per millimeter is better, although the human eye is limited in the number of line pairs it can discern without magnification. Dental film is generally thought of as having more than 15 line pairs per millimeter. Current CCD based sensors systems are advertised as having from eight to 12 line pairs per millimeter, although much greater resolution (22 line pairs) is possible and will be shortly forthcoming from at least one developer. The signal-to-noise ratio is a measurement of the relative fidelity and clarity of the image signal against the interference from background noise. Obviously, the less noise and the stronger the signal, the better the image will be.

Film is not only the standard of comparison for diagnostic quality, but also for image size. Initially, sensors were small and bulky. Now, the active area of several sensors compares favorably to intraoral radiographic films. The active area of the sensor is less than the physical size of the sensor, since it must be encased in a hard, hermetically sealed housing.

CCD Design

The thickness of the sensor has been a matter of concern to many, since CCD sensors are all thicker than film. Sensors have become progressively thinner, with current models being between 5 and 9 millimeters and averaging approximately 6 millimeters. Much thinner sensors, 3.2 millimeters, are likely to appear on the market in the near future. The incorporation of the fiberoptic conductor between the phosphor screen and the sensor protects the CCD from direct irradiation, but sensors without a fiberoptic component can be made thinner. Such sensors have been marketed in the past, and a CCD sensor without a fiberoptic screen and using another method of sensor protection will be available soon. Again, image quality is the primary element of comparison, and advertising claims for one system or another should be supported or discounted based primarily on this criterion.

Phosphor Plates, Film, and CCDs

Phosphor plate systems, also termed PhotoStimulable Phosphor plate, or PSP, are an alternative to CCD sensors. These systems use a phosphor plate -- a film-like package -- that is stimulated by the radiation and then removed from the mouth and "read" by a scanning unit. Sensors come in numerous sizes including those for occlusal and panoramic views. This system is described in detail elsewhere in this issue (see The Integration of Filmless Radiology in a Restorative General Practice, by Arlen Lackey.) The phosphor plate "film" has an additional advantage of being flexible, whereas a flexible CCD system is, today, impossible. A primary advantage of the CCD sensors is the rapidness of processing. Current CCD systems often advertise "instant developing' whereas the actual time from image acquisition to image display may range from four to 10 seconds, and sometimes more. Nonetheless, this is far faster than either film or the phosphor plate systems. Furthermore, the image for the CCD systems is displayed while the sensor is still in position, and if correction is needed, the sensor only need be moved from the known position to the desired position. This is a great advantage, especially when the radiograph is being used for endodontics or for implant evaluation or, perhaps, locating a root tip during surgery. Since both film and phosphor plates require extraoral processing, this advantage is lost. A great advantage of the phosphor plate systems is the absence of a connecting cable. CCD systems without the cord and using radio frequency or infrared transmission technology will probably appear, but none are now available.

An advantage of both CCD and phosphor technologies over film is the reduction of the radiation burden. Although manufacturers advertise up to 90 percent reduction, this is not without diminished diagnostic quality. For some uses, such reductions are achievable and realistic.

Imaging Software

Fig 3. A cephalometric radiograph that has been colorized by a digital radiography software program. The soft tissue outline is clearly visible.
The software for a digital radiographic system is a major consideration. All image signals require initial processing to optimize image quality. Additional basic functions include image enhancement features such as incremental contrast and brightness adjustment, coloration, image rotation, image pan and zoom, grey level (gamma) correction, and image annotation. Image measurement is also helpful, but distortions may be misleading, and measurements should be considered relative, even when some form of calibration is used.

The coloration feature is often marketed as being a unique and useful feature. Actually, coloration discards a considerable amount of information by assigning a color to a range of gray levels. Coloration can be helpful, however, when attempting to define the features of a given gray level, such as the soft tissue outline of a cephalometric film, which might otherwise be difficult to discern (Figure 3). Reverse imaging (transposition of the blacks and whites) can sometimes be helpful in image evaluation.

Many companies offer free demonstration software that can be downloaded from their web site for trial. The reader is encouraged to explore the web site addresses provided and take advantage of "home shopping" for computer radiography. Some of the web site addresses for demonstration software are:

www.apteryxware.com

www.televere.com/product.htm (online request for demonstration software)

www.trophy.com (download)

www.schicktech.com (download)

Imaging software should be seamlessly integrated with office management and patient record software. The imaging software should enable the user to import images, not only from the CCD source, but also from scanned sources. Twain, an industry-wide accepted protocol for scanners that is included with Microsoft Windows 95, makes importing images a simple matter. Unfortunately, not all digital systems consider Twain-compliance necessary and some companies that were contacted in preparation of this article seemed ignorant about its usefulness.

Most medical imaging systems also support a standard protocol recommended by the American College of Radiology called DICOM (Digital Imaging and Communications in Medicine). Those who have been primary supporters and developers of digital radiography in dentistry have been active advocates of the standard. More information about Twain and DICOM can be found at:

www.whatis.com/twain.htm

www.twain.org/about.htm

ddsdx.uthscsa.edu/dicom/dicom.html

Security

One of the questions that often arises is, "How can I be assured that the image I see is an original, unaltered image?" This is a good question, since digital images can be easily altered, and the unknowing observer may be deceived. Insurance companies need to know that the conditions presented on the radiograph do, indeed, exist in the patient. This issue has been addressed in a number of ways. The most recent approach is by Eastman Kodak, who developed what has been called "Kodak DNA". The original image is given a file name extension that indicates that it is an original image. All pixels in the original image are mapped and recorded. Only the original image is given the delineating suffix, and all modifications are recorded differently. This development is relatively recent, and the success of the system is currently unclear. However, several leading software manufacturers are offering the system. Another method is known as a "secure tagged block". Original images are saved with an "stb" file type delineation (i.e. "filename.stb") and no alterations are permitted to the original image. Other systems are sure to evolve, and their success will be dependent upon the acceptance by third parties that authorize and remunerate dental care based on radiographic evidence.

Web site addresses of interest include:

www.kodak.com/US/en/health/dental/softwareMenu.html

www.apteryxware.com

www.televere.com/product.htm

CMOS Technology

Another emerging type of sensor uses a different silicon semiconductor technology. Complementary metal oxide semiconductor (CMOS) devices are beginning to appear in dental digital radiology. CCD sensors are n channel silicon devices and can be considered a subset of CMOS technology.⁶ CMOS technology uses both the p and n channel transistors on the same chip - therefore the name "complementary". CCDs are said to offer the greatest sensitivity and fidelity. Advantages that are claimed for the CMOS technology include the need for a less energy to record an image and the highest level of integration that can reduce system cost. A negative aspect can be greater signal-to-noise ratio. However, an amplifying element can be incorporated to overcome this shortcoming.

It is probable that future digital radiology devices will use a combination of CCD and CMOS technology to obtain the greatest advantages of the two technologies. It is beyond the scope of this paper to expand on the physics of these devices. Suffice it to say that the technology is relatively young but is emerging rapidly. Additional information can be found at www.suni.com/pages/laserf.htm.

Computed Radiography in Dentistry and the Internet

Almost as rapidly as information can be published, innovations and alterations make it obsolete. Readers are encouraged to use the power of the Internet to seek information on the many digital radiography systems available. The following list of web site addresses should prove helpful:

CCD or CMOS sensors:

Cygnus (Panasonic) http://www.zila.com/cygnus/cygnusray.htm

Dent-X (Raegam) http://www.dent-x.com/SensaView.html

Dexis meros.com/au/html/dexis.htm

Dimax, panoramic http://www.planmeca.com

Dixi http://www.planmeca.com/

Ni-DX (Dentsply-New Image) http://www.dentsplynewimage.com/NI-DX.html

Schick http://www.schihcktech.com

Sidexis (Sirona) http://www.sirona.de/e/index2.html or http://www.sident.co.uk/sidexis.html

Digital intraoral, panoramic, and cephalometric radiography

Trophy http://www.trophy.com

Stimulated Phosphor Technology:

Soredex http://www.soredexusa.com/default.htm

Dentoptix http://www.gendexxray.com/denoptix.htm

Other Benefits

In addition to the reduction in the radiation burden to the patient, digital radiography offers some other tangible benefits. Since the use of chemicals is obviated, there is no concern about the disposal of processing waste. This has become an issue, especially in metropolitan areas. Furthermore, although the cost of a digital radiography system is higher initially, there are fewer ongoing costs, such as the purchase of film, processing chemistry, or processors. The increasing acceptance of digital patient records mandates the incorporation of radiographs, and digital acquisition is preferable to scanning. Radiographs are not lost, and they are filed in an orderly and easily retrievable manner. This is a vast improvement over the typical random search through a myriad of envelopes and a sequence of complete mouth or bitewing mounts with which most clinicians are familiar.

As sensor technology improves and professional response makes additional investments in research feasible and profitable, improvements in digital radiography will accelerate. As this occurs, the use of film will diminish. Whether or not film will ever be replaced is a matter of conjecture.

Computer Assisted Design, Computer Assisted Manufacture (CAD/CAM)

Dental CAD/CAM has been in development for over 24 years, but has yet to be broadly accepted. It is evolving, however, and may eventually be practical in ways quite different than originally conceived. The CEREC system by Sirona has been the most commercially successful. It has evolved through two iterations, CEREC I, and CEREC II. The first used a single 3 centimeter diamond disk, and had limited resolution (256 x 256 - 8 bit). The software was also somewhat limited and the accuracy was questioned. The current system, CEREC II, uses both the diamond disk and a 2 millimeter diameter diamond point. The resolution has been doubled to 512 x 512. The software is also much improved, offering more automatic features. It also added the opportunity to define the third dimension of cusp height and groove position. These features are, however, somewhat limited. The system was designed for the chairside fabrication of ceramic inlays and onlays. More recently software has been added to allow the fabrication of crowns. Obviously the internal accuracy of such restorations is limited by the cutting tools available. More information may be gleaned from the Sirona web site at: http://www.sirona.de/e/index2.html.

The Japanese have been very active in the research and development of CAD/CAM programs. The Japanese government has underwritten a substantial portion of such investigations, but private industry has also contributed greatly. The recent introduction of the CAPS (Computer Assisted Prosthodontic System) follows the more traditional concept of CAD/CAM and is an impressive unit that uses automated laser point scanning to digitize the die. The system was developed by Nikon and although it is not commercially available in the United States it was exhibited at a recent dental meeting. Other systems are advertised but not available in the US. An example is a system found on the Internet at: http://www.advance.co.jp/dental-cadim/index-e.html.

Fig 4. The die is contact-digitized to acquire a three-dimensional image.
Noble BioCare, in conjunction with Sandvik, has developed a quite different use of CAD/CAM and redefines the role of the dental technician. The preferred tooth preparation for this all-ceramic system is a chamfer margin. Impressions are made as for a conventional restoration, and the dies sent to the dental laboratory. The dies are then traced by an automatic machine that produces a digital three-dimensional representation of the master die (Figure 4). The technician then defines the features of the die, marks the margin, and designs the coping (Figure 5).

Fig 5. The coping is designed on the digital image.
These digital data are then sent electronically to the corporate laboratory in Sweden. There a die is recreated by the CAM process, but the dimensions of the new die are expanded three-dimensionally to compensate for the shrinkage of the porcelain that will be formed upon it. A process termed "isostatic pressing" is used to form aluminum oxide ceramic onto the die. This process is not possible in a dental laboratory because of the high sintering temperature of alumina. This material is then completely sintered, resulting in an unusually strong ceramic coping (Figure 6).

Fig 6. The coping is returned to the laboratory.
This material is, however, opaque, and the completed restoration is veneered to achieve the desired esthetic result. This, of course, requires the same technique and skill needed for any other esthetic ceramic restoration. Excellent functional and esthetic results are possible (Figure 7). More information on the Procera system may be found at: http://www.nobelbiocare.se/acomp/procera.htm.

Fig 7. The completed restoration on the right central incisor. (Courtesy Rotaert Dental Laboratory, Hamilton, Ontario BC.)

Computed Color Matching:

Every dentist who places esthetic restorations has at one time or another been frustrated by the process of trying to match the color of natural teeth with ceramic or resin restorations. Conventional shade guides have severe limitations, both in design and in product execution. Even the latest iterations of shade selection systems do not cover the dental shade range. It would seem that in today's highly technical world we should be able to develop a computer-based shade selection device. After all, there are spectrophotometers at the local paint store and automobile paint shops use a spectrophotometer for your car repair. Why doesn't the dentist have one for shade selection? Unfortunately, the dental color measurement problem is very complex. It has been said⁷ that the dental shade selection problem is the most difficult of all color measurement situations. Teeth have every difficulty that can be encountered: they fluoresce, are inhomogeneous and translucent, and have small, irregular surfaces. In the past, several devices have attempted to solve the instrumental approach to dental color measurement. All failed. Today there are several devices that are presently, or soon will be, offered to the dental profession. "Pikkio", (Figure 8),

Fig 8. The Pikkio Spectrophotometer.
a development of a Swiss and Italian venture, briefly entered the marketplace and is currently being refined. It is a hand-held unit that can be downloaded to a computer. The device gives the user the closest Vita® shade guide, and the amount by which the tooth varies from it. Additional information may be found at: http://www.mht.it/.

Fig 9. Wolf Industries DCS Spectrophotometer.
Wolf Industries of Vancouver, BC (http://www.wolfindustries.com) will soon market a device that provides the nearest match to both the Vita® and Ivoclar® shade guide, and the amount by which the tooth differs from the guide (Figure 9). Shofu Dental Corporation is said to be ready to offer a device researched by the group at Iwate University in Japan. The exact software behind this device has not been released as of this writing. The appearance of multiple devices attempting to solve this problem is testimony that the scientific community recognizes the need for assistance in dental shade selection, and the willingness to underwrite the development of a solution. In addition to the devices cited, several others are known to be under development. Certainly, most restorative dentists would welcome reliable technical support in shade selection and color matching. However, the device would be most helpful if it not only correctly analyzed the tooth color, but also the optical properties such as translucency and surface gloss. Restorative materials correlated to these readings should then be developed to optimize predictable results.

Intraoral Cameras

Fig 10. Intraoral cameras have progressively decreased in size from the original cart-based systems to the recently introduced hand held wireless portable model with self-contrainedd monitor focusing.
There is no doubt that the greatest success in digital dental adjuncts has been the acceptance of intraoral cameras. It is estimated that approximately 45 percent of the dentists in the US have intraoral cameras. The market growth has slowed, but to many practitioners, the intraoral camera is an essential part of the clinical armamentarium. When intraoral cameras were first introduced they cost $25,000. Today cameras can be found for under $2,000 and up to almost $10,000. Initially, all cameras were cart based. The idea was to move the cart with the camera and a printer (and, perhaps, a computer) from operatory to operatory, as it was needed. While the concept was simple, the implementation was not, and dentists soon found that the "mobile" cart was awkward, and was rarely moved. Today's intraoral cameras have become progressively smaller, easier to use, and more "user friendly" (Figure 10). Many intraoral cameras allow the placement of docking stations and only the camera is moved from room to room. Most dentists that have found the practicality of intraoral cameras have made the investment in multiple units to solve the problem of availability, and have networked the units to a single printer.

Although there is a substantial price variation, purchasers should evaluate their needs, and consider price versus performance. There are at least 20 vendors today, and the same product may be sold under different brand names. Networking the operatories permits using one camera in multiple rooms, or to file images on a server from any room. Some cameras have an on-board chip that precludes the need for a computer to print images on a centralized printer. If images are to be filed in the computer, a digitizing board is needed to capture images from an analog camera. Actually, all images are initially digital, as they are acquired from a CCD (Figure 1), and converted to analog format for display. Digital cameras preclude the need for a digitizing board.

There are numerous cameras with various features and preference for a given camera may be an individual matter. Many factors should be considered.⁸ The camera should be easily focused, produce a clean, sharp, true-color image, and be protected from cross-contamination. Cameras should be able to capture an image of a complete arch, and be capable of focusing down to a single tooth. It is helpful if the camera is activated upon being picked up. A number of cameras are now cordless. This is a convenient feature, but it may limit the brightness, since there is no fiberoptic connection to an AC light source. The most productive way to explore each system is to surf the Internet sites and review the merits of each product and then ask for local demonstrations of selected products. Table I provides the source, product name and web site address for a number of cameras. As with all products that require a substantial investment, it is recommended that prospective buyers request a list of previous customers who can be contacted to ascertain their appraisal of the product.

SOURCE

PRODUCT

WEB SITE ADDRESS

Air Techniques

VistaCam Omni

None

Computer Age Dentist

CADcam

http://www.computeragedentist.com/software/CADcam.html

Cygnus

Cygnascope 500, Oral Vision 1000

http://www.zila.com/cygnus/index.htm

DMDS

Telicam, Telicam Elite

http://www.dmdcorp.com/telicam.html

Dentsply (New Image)

AccuCam Concept III

http://www.dentsplynewimage.com/acucam_concept3.html

AccuCam Polo

http://www.dentsplynewimage.com/acucam_polo.html

Dent-X

Sens-a-View

http://www.dent-x.com/SensaView.html

Digital Doc

DigiDoc Alntroral

http://www.digi-doc.com

Doctor Direct Sales

Opticam

None

Integra Medical

ViperCam

http://www.vipersoft.com/(under construction)

Planmeca

Intracam

http://www.planmeca.com/eng/prod/prodcat/crframes.html

RF Syste Lan

Satellite Scope

None

Schick

CDR Cam

http://www.schicktech.com/techspec.htm#cdrcam

Spectra VU

SpectraVu 1000,2000

Web site not operational currently

Sullivan-Schein

Easy Cam Ultralite II

http://www.henrytschein.com (Web site not specific for camera)

Trophy

STV

http://www.trophy-imaging.com

Ultracam

Ultracam

http://www.ultracam.com/products.html

Video Dental Supply

Quickcam 4.1

Oral Videoscope

ViperCam

http://www.videodental.com/cameras/htm

Welch-Allyn (Patterson)

Reveal SLR

Reveal MLR

None

Typically, images are filed in the patient's record and should be easily accessible, just as radiographs are filed. Image management software is helpful in modifying images, and simple maneuvers such as cropping, rotating, changing brightness and color balance are found in most basic programs. Cosmetic imaging software which enables altering the image to help plan the treatment outcome can also be helpful. Such programs have a significant learning curve, and to make the process more productive, it is often delegated to a non-dentist employee.

An intraoral camera in the hygiene area is of great help. Patients can see their original condition and be shown where they are lax in their oral care. Areas of concern can be recorded and filed, either as photographs printed and appended to the chart, or filed digitally in the patient's virtual chart. The dentist can then review the images when the patient is being treated.

Images may also be transmitted to the dental laboratory with the casts and work request. This is particularly helpful when anterior esthetic restorations are requested. Video images and radiographs may also be sent to other dentists to whom the patient might be referred.
The absolute ease of appending images to e-mail messages should not be overlooked by practitioners. In moments an image can be acquired, filed in the patient's record, and sent to another dentist, the dental laboratory, or to the third party payer. There are many additional methods of transmitting images via computer, and as modem speeds increase, the time of transmission becomes more reasonable.

Dentistry is a very "visual" profession and the intraoral camera is a valuable communication tool. Patients become interested in how, rather than if, to treat their condition, resulting in increased practice income. Image acquisition and storage is also a useful tool for documentation, and provides a record of the sequence of therapy.

Periodontal Devices

Crevicular depth probing is an essential diagnostic procedure to determine relative periodontal health. It is also time-consuming and often neglected. It would seem that a device that could automate this procedure would meet with rapid clinical acceptance. Even though such devices have been available for years, they have yet to find substantial commercial success. Several such devices are available, and have documented accuracy.⁹ Many devices have been marketed under different names, as some companies have failed to maintain economic viability and have been acquired by others.

Perhaps as the computer finds its way into the clinical operatory for other applications, the automated periodontal probe will finally become more feasible. Certainly, the digitization of probing facilitates recording, since a single individual can make the record without picking up a writing instrument or calling out the probing depths to an assistant. Automated probes deliver a calibrated probing pressure. Furthermore, the results are charted, and the various systems have differing methods of presenting the results to the patient. With at least one system, the computer calls out the recordings in either a male or female synthesized voice, obviating the need for the operator to look up at the monitor during probing. Bleeding and suppuration are also entered.

Patients have a much better comprehension of the procedure when they can see a graphic result, which seems to result in a greater interest in their periodontal health. Three web sites are worth checking for further information on periodontal probing:

Florida Probe http://www.floridaprobe.com/

Interprobe http://www.interprobe.com/

Probe One, Interprobe americandentaltech.com/probe.html

Some devices are dependent upon the computer for recording information while others offer a stand-alone solution. The most effective use is the total integration into a virtual patient record.

Conclusion

There are many other devices that are available for use in the dental operatory. The success of the ventures underwriting these devices is dependent upon the migration of the computer into the treatment area. As this happens, the individual devices become less onerous to incorporate into the treatment regimen. This paper has not addressed the subject of practice management or clinical record software. Dental software acceptance is critical to the overall implementation of digital devices. Integration of all devices with the patient record should be seamless, transparent, and obvious. As more dentists become comfortable with computer use, the integrated use of digital devices should escalate, and patient care should be simplified and improved. The Internet is a valuable tool for accessing information on many dental topics and should be used by any dentist that wishes to obtain current information on a wide variety of topics. The half-life of knowledge is increasingly shorter and it is the obligation of all practitioners to update the information upon which their practice is based.¹⁰ The opportunities for electronically refreshing one's knowledge base are rich and deep. No professional person should overlook this resource.

Author

Dr. Preston is chairman of the department of oral and maxillofacial imaging at the University of Southern California School of Dentistry and is the Don and Sybil Harrington Foundation Professor of Esthetic Dentistry.

References

1. http://http://www.mhmeyerson.com/ research /dmds/dmds09.htm.

2. Suni, P, Keynote paper, Seventh Annual IEEE International Conference on Wafer-Scale Integration, 1995, http://http://www.suni.com/pages/wsipaper.htm.

3. Suni P, Advanced design creates single-chip vision systems. Reprint from Laser Focus World, April 1997. http://http://www.suni.com/pages/laserf.htm.

4. Suni, P, Custom photodetector arrays meet design challenges. Reprint from Laser Focus World, April 1994, http://http://www.suni.com/pages/lasrfoc.htm.

5. Khademi J, Direct Digital Radiography: Preliminary review of Three FDA-Approved Systems. CDA Journal, 22(11):48-56, 1994.

6. Matsumoto C, Startup develops a CCD-CMOS hybrid, in Electronic Engineering Times Issue 935, 1/6/1997, http://http://www.suni.com/pages/eet935.htm.

7. Clark, FJJ, Proceedings of the First International Symposium on Ceramics. Quintessence Publishing Co, Chicago Ill. and Berlin, W. Ger, 1983.

8. Johnson L, A Systematic Evaluation of Intraoral Cameras, CDA Journal, 22(11):34-47, 1994.

9. Oringer RJ, Fioellini JP, Koch,G, Sharp TJ, Nevins,ML,Davis,GH, and Howell TH, Comparison of Manual and Automated Probing in an Untreated Periodontitis Population, J Periodontol 1997;68:1156-1162

10. Preston JD, Computers in Dental Education, CDA Journal, 1997; 25(10):729-733

For printed copies of this article, please contact / Jack D. Preston, DDS, USC School of Dentistry, University Park, Los Angeles, CA 90089.

JOURNAL OF THE CALIFORNIA DENTAL ASSOCIATION
©1998 CALIFORNIA DENTAL ASSOCIATION