- Email: [email protected]
Conebeam computed tomography
Table 1.—The Commonly Presenting Signs and Symptoms Seen in Cases of Cracked Tooth Syndrome (CTS) Sudden, sharp pain on biting/chewing and in some cases on release: ‘rebound pain’ Sensitivity to cold thermal stimuli; in some cases hyper-reactivity to hot/sugary stimuli may also occur Symptoms may be present for periods ranging from weeks to months Inconsistent ability to localise the affected tooth Pain may be elicited by lateral cusp pressure, as evoked by ‘bite tests’ and tooth grinding Fracture lines may be seen clinically (sometimes upon removal of the restoration), aided by magnification, dyes or transillumination Positive response to vitality tests; exaggerated response to cold thermal stimuli Radiographs; usually inconclusive
are a maximum of 3 mm below the periodontal attachment generally have an excellent prognosis. Having both marginal ridges involved, pulp involvement, and fractures extending vertically through the pulp or involving the subpulpal floor have a poor prognosis. The prognosis is termed hopeless when there is a complete mesiodistal fracture and the fractured segment cannot be removed or exposed through gingivoplasty or alveoplasty. Other prognostic factors include tooth and root anatomy, previous history of surgery or restorations, and functional forces applied to the tooth. It is best to recognize the CTS early to prevent further cracking. Loss of pulp vitality is a negative prognostic influence, along with endodontic treatment. The operator’s skill and experience can contribute prognostically, with management choice also influential.
(Courtesy of Banerji S, Mehta SB, Millar BJ: Cracked tooth syndrome. Part 1: Aetiology and diagnosis. Br Dent J 208:459-463, 2010.)
diagnosis of CTS. Stains can also be used to identify fracture lines, but it takes several days to be effective and may require having a provisional restoration placed, with the potential to further undermine the structural integrity of the tooth. Placing a definitive esthetic restoration may also be compromised when a dye is used. Bite tests should only be given once the patient has been advised that cuspal fragmentation may result. Commercially available diagnostic tools include the Fractfinder and Tooth Slooth (Fig 4). Generally, the results of vitality testing are positive in cracked teeth, but hypersensitivity may also be shown. Apical percussion seldom provokes a positive response. Prognosis.—The key factors determining the prognosis in CTS are the location and extent of the crack. Cracks confined to the dentin that run horizontally and do not involve the pulp and those limited to a single marginal ridge that
Clinical Significance.—Understanding the epidemiology, etiology, pathophysiology, diagnostic challenges, and prognosis associated with CTS will help the practitioner handle this problem. An accurate diagnosis obtained early in the course of the fracture and appropriate management yield the best prognosis.
Banerji S, Mehta SB, Millar BJ: Cracked tooth syndrome. Part 1: Aetiology and diagnosis. Br Dent J 208:459-463, 2010 Reprints available from BJ Millar, Dept of Primary Dental Care, King’s College London Dental Inst, Bessemer Rd, London, SE5 9RW; e-mail: [email protected]
Dental Imaging Conebeam computed tomography Background.—Conebeam computed tomography (CBCT) offers a greatly reduced radiation dose compared with conventional computed tomography (CT) and a lower cost for purchasing the CBCT machine. Because of the affordable cost, CBCT machines are increasingly being made available within the dental office. Some professional oral and maxillofacial radiology organizations offer published guidelines for the use of CBCT, but the exact role of this modality in dentistry is not yet clearly defined. Legal issues have arisen concerning its use, including ownership, image volume, interpretation, licensure, and insurance questions.
Ownership.—Manufacturers now make ‘‘mini’’ CBCT machines, so it is possible for most U.S. dentists to own them and expose their images. However, in some areas patients are referred to dental x-ray laboratories. Legally, most states allow the licensed dentist to own and operate personal CBCT machines without the requirement of any training apart from that taken in dental school. States in which dental x-ray laboratories are common often require owners of such laboratories to be appropriately trained and have passed an examination, even if they are not dentists. Many states in the United States and other countries limit
Volume 55
Issue 6
2010
297
the number of CT scans, magnetic resonance imaging, positron emission tomography, and other advanced imaging equipment that can be available in a specific area. Purchase of such machines is controlled through certificates of need. Laws may also require that CBCT machines must be operated by registered medical radiology technicians, radiologists, or other specially trained health care professionals. To avoid problems, the dentist should make sure all requirements are met before purchasing and operating CBCT devices. Sales personnel of such equipment may be unaware of the specific laws pertaining to these issues, so it is advisable to check with the state agency that licenses, inspects, and tests the radiology equipment. A complication may arise if the dentist decides to purchase the machine in partnership with a physician. In that case, the dentist may become subject to laws pertaining to physicians, such as the Stark Law and the federal antikickback statute. The dentist should check with review medical boards for their regulations applying to physicians owning a CBCT. Image Volume.—The indications for and extent of imaging should be based on the clinical indications for the investigation. These principles are designed to protect the patient’s and the public’s health from unnecessary exposure to radiation. Some dentists may expand the area too far, exposing structures that are not pertinent to the patient’s signs and symptoms. Others may collimate too narrowly, sometimes because they want to avoid anatomic structures they feel unprepared to interpret. Orthodontists and practitioners who perform implant surgery are often not trained to interpret films beyond the anatomy they see on a daily basis. Interpretation.—Dental x-ray laboratories with CBCTs and some medical radiology facilities performing DentaScan imaging studies do not interpret the scans. Instead, they offer a disclaimer. Dentists who take their patients’ scans or who use facilities to obtain them and do not provide a report may be liable for the scan’s reading. The dentist is responsible for reading the scan because it applies to their area of practice or the indication for the scan as well as for reading all the structures included in the scan. A waiver of liability does not actually limit the dentist’s liability, nor can the responsibility be shifted to patients. Patient choices are limited by the boundaries of accepted standards of care, and none of the choices should be less than those standards. Licensure.—Dentists can refer CT scans out for reading by a radiologist. Such referrals must be made to a competent practitioner. Dentists are considered competent to read CTs only if they have completed a formal program in oral and maxillofacial radiology. Generally, the referral is accomplished by uploading the case to a server, where the radiologist downloads and interprets the images, and then sends back a report. Sometimes, the radiologist can log on
298
Dental Abstracts
directly to the dentist’s computer and read the images. Licensing laws to cover referrals can be problematic if they require that the radiologist be licensed in the state in which the dentist practices. Teleradiology, or reading images over the Internet, can be performed by radiologists and dentists located anywhere in the world. There are no uniform regulations currently present to address this situation. Dentists cannot circumvent the situation by classifying the interaction as a ‘‘second opinion,’’ which does not fall under the licensing regulations. A true second opinion is a one-time or occasional consultation and is given only when the dentist has already provided a diagnosis. Submitting CBCT scans for reading by a regular consultant radiologist would not fall into either of these categories. Insurance.—Insurance carriers may not cover radiologists who read images from dentists who are out of state or out of the country. Often malpractice insurance is limited to states where the practitioner took out the coverage and/ or where he or she is licensed. Should the patient be dissatisfied or other adverse outcomes occur, the patient may sue both the radiologist and the dentist. Currently such suits are rare, but the potential is present. Discussion.—Dentists seeking to acquire a CBCT machine should take steps to avoid the problems outlined. It is suggested that they (1) make sure the law of the jurisdiction in which they practice does not limit either ownership or operation of such devices, (2) be prepared to read the entire image volume or arrange for it to be read by a competent professional, (3) check with the dental board or boards to ensure that the radiologist reading the image is appropriately licensed, and (4) confirm that any out-of-state radiologist to whom cases are referred carries malpractice coverage and that their own coverage includes out-of-state practice.
Clinical Significance.—Although not all the licensing regulations have caught up to the technology of the Internet, it is essential to follow the current laws of the land. Dentists who want to include CBCT in their practices must either invest in the training to interpret all possible structures appropriately or connect with a radiologist who is appropriately licensed and trained to provide accurate interpretations. The incorporation of CBCT scans in a dental practice must be carefully considered in light of these legal complications.
Friedland B: Conebeam computed tomography: Legal considerations. Alpha Omegan 103:57-61, 2010 Reprints not available
are a maximum of 3 mm below the periodontal attachment generally have an excellent prognosis. Having both marginal ridges involved, pulp involvement, and fractures extending vertically through the pulp or involving the subpulpal floor have a poor prognosis. The prognosis is termed hopeless when there is a complete mesiodistal fracture and the fractured segment cannot be removed or exposed through gingivoplasty or alveoplasty. Other prognostic factors include tooth and root anatomy, previous history of surgery or restorations, and functional forces applied to the tooth. It is best to recognize the CTS early to prevent further cracking. Loss of pulp vitality is a negative prognostic influence, along with endodontic treatment. The operator’s skill and experience can contribute prognostically, with management choice also influential.
(Courtesy of Banerji S, Mehta SB, Millar BJ: Cracked tooth syndrome. Part 1: Aetiology and diagnosis. Br Dent J 208:459-463, 2010.)
diagnosis of CTS. Stains can also be used to identify fracture lines, but it takes several days to be effective and may require having a provisional restoration placed, with the potential to further undermine the structural integrity of the tooth. Placing a definitive esthetic restoration may also be compromised when a dye is used. Bite tests should only be given once the patient has been advised that cuspal fragmentation may result. Commercially available diagnostic tools include the Fractfinder and Tooth Slooth (Fig 4). Generally, the results of vitality testing are positive in cracked teeth, but hypersensitivity may also be shown. Apical percussion seldom provokes a positive response. Prognosis.—The key factors determining the prognosis in CTS are the location and extent of the crack. Cracks confined to the dentin that run horizontally and do not involve the pulp and those limited to a single marginal ridge that
Clinical Significance.—Understanding the epidemiology, etiology, pathophysiology, diagnostic challenges, and prognosis associated with CTS will help the practitioner handle this problem. An accurate diagnosis obtained early in the course of the fracture and appropriate management yield the best prognosis.
Banerji S, Mehta SB, Millar BJ: Cracked tooth syndrome. Part 1: Aetiology and diagnosis. Br Dent J 208:459-463, 2010 Reprints available from BJ Millar, Dept of Primary Dental Care, King’s College London Dental Inst, Bessemer Rd, London, SE5 9RW; e-mail: [email protected]
Dental Imaging Conebeam computed tomography Background.—Conebeam computed tomography (CBCT) offers a greatly reduced radiation dose compared with conventional computed tomography (CT) and a lower cost for purchasing the CBCT machine. Because of the affordable cost, CBCT machines are increasingly being made available within the dental office. Some professional oral and maxillofacial radiology organizations offer published guidelines for the use of CBCT, but the exact role of this modality in dentistry is not yet clearly defined. Legal issues have arisen concerning its use, including ownership, image volume, interpretation, licensure, and insurance questions.
Ownership.—Manufacturers now make ‘‘mini’’ CBCT machines, so it is possible for most U.S. dentists to own them and expose their images. However, in some areas patients are referred to dental x-ray laboratories. Legally, most states allow the licensed dentist to own and operate personal CBCT machines without the requirement of any training apart from that taken in dental school. States in which dental x-ray laboratories are common often require owners of such laboratories to be appropriately trained and have passed an examination, even if they are not dentists. Many states in the United States and other countries limit
Volume 55
Issue 6
2010
297
the number of CT scans, magnetic resonance imaging, positron emission tomography, and other advanced imaging equipment that can be available in a specific area. Purchase of such machines is controlled through certificates of need. Laws may also require that CBCT machines must be operated by registered medical radiology technicians, radiologists, or other specially trained health care professionals. To avoid problems, the dentist should make sure all requirements are met before purchasing and operating CBCT devices. Sales personnel of such equipment may be unaware of the specific laws pertaining to these issues, so it is advisable to check with the state agency that licenses, inspects, and tests the radiology equipment. A complication may arise if the dentist decides to purchase the machine in partnership with a physician. In that case, the dentist may become subject to laws pertaining to physicians, such as the Stark Law and the federal antikickback statute. The dentist should check with review medical boards for their regulations applying to physicians owning a CBCT. Image Volume.—The indications for and extent of imaging should be based on the clinical indications for the investigation. These principles are designed to protect the patient’s and the public’s health from unnecessary exposure to radiation. Some dentists may expand the area too far, exposing structures that are not pertinent to the patient’s signs and symptoms. Others may collimate too narrowly, sometimes because they want to avoid anatomic structures they feel unprepared to interpret. Orthodontists and practitioners who perform implant surgery are often not trained to interpret films beyond the anatomy they see on a daily basis. Interpretation.—Dental x-ray laboratories with CBCTs and some medical radiology facilities performing DentaScan imaging studies do not interpret the scans. Instead, they offer a disclaimer. Dentists who take their patients’ scans or who use facilities to obtain them and do not provide a report may be liable for the scan’s reading. The dentist is responsible for reading the scan because it applies to their area of practice or the indication for the scan as well as for reading all the structures included in the scan. A waiver of liability does not actually limit the dentist’s liability, nor can the responsibility be shifted to patients. Patient choices are limited by the boundaries of accepted standards of care, and none of the choices should be less than those standards. Licensure.—Dentists can refer CT scans out for reading by a radiologist. Such referrals must be made to a competent practitioner. Dentists are considered competent to read CTs only if they have completed a formal program in oral and maxillofacial radiology. Generally, the referral is accomplished by uploading the case to a server, where the radiologist downloads and interprets the images, and then sends back a report. Sometimes, the radiologist can log on
298
Dental Abstracts
directly to the dentist’s computer and read the images. Licensing laws to cover referrals can be problematic if they require that the radiologist be licensed in the state in which the dentist practices. Teleradiology, or reading images over the Internet, can be performed by radiologists and dentists located anywhere in the world. There are no uniform regulations currently present to address this situation. Dentists cannot circumvent the situation by classifying the interaction as a ‘‘second opinion,’’ which does not fall under the licensing regulations. A true second opinion is a one-time or occasional consultation and is given only when the dentist has already provided a diagnosis. Submitting CBCT scans for reading by a regular consultant radiologist would not fall into either of these categories. Insurance.—Insurance carriers may not cover radiologists who read images from dentists who are out of state or out of the country. Often malpractice insurance is limited to states where the practitioner took out the coverage and/ or where he or she is licensed. Should the patient be dissatisfied or other adverse outcomes occur, the patient may sue both the radiologist and the dentist. Currently such suits are rare, but the potential is present. Discussion.—Dentists seeking to acquire a CBCT machine should take steps to avoid the problems outlined. It is suggested that they (1) make sure the law of the jurisdiction in which they practice does not limit either ownership or operation of such devices, (2) be prepared to read the entire image volume or arrange for it to be read by a competent professional, (3) check with the dental board or boards to ensure that the radiologist reading the image is appropriately licensed, and (4) confirm that any out-of-state radiologist to whom cases are referred carries malpractice coverage and that their own coverage includes out-of-state practice.
Clinical Significance.—Although not all the licensing regulations have caught up to the technology of the Internet, it is essential to follow the current laws of the land. Dentists who want to include CBCT in their practices must either invest in the training to interpret all possible structures appropriately or connect with a radiologist who is appropriately licensed and trained to provide accurate interpretations. The incorporation of CBCT scans in a dental practice must be carefully considered in light of these legal complications.
Friedland B: Conebeam computed tomography: Legal considerations. Alpha Omegan 103:57-61, 2010 Reprints not available