Journal of
Oral Rehabilitation
Journal of Oral Rehabilitation 2014 41; 630--634
Laser light passage through restored and carious posterior teeth N. P. CHANDLER*, T. R. PITT FORD*2 & B. D. MONTEITH†
*The Sir John Walsh Research
Institute, School of Dentistry, University of Otago, Dunedin, New Zealand and †Department of Conservative Dentistry, Dental Institute, King’s College London, London, UK
Laser Doppler flowmetry (LDF) has been used to investigate pulpal blood flow as a means of pulp vitality testing. Transmission of laser light from the tooth surface to the pulp space may be influenced by caries and restorations. One hundred and twenty-two first and second molars that had caries into dentine, restorations or significant loss of coronal tissue were sectioned in half axiobucco-lingually. The two sections were illuminated with a laser from their buccal and lingual aspects 2 mm coronal to the amelocemental junction. Light reaching the pulp space was recorded. Buccal and lingual illumination sites were equally effective for 67 teeth (55%). Buccal sites alone were effective for 35 teeth (29%), despite over one-third of these surfaces being restored or featuring enamel or SUMMARY
Introduction Diagnosis of pulp disease may be problematic (1). Laser Doppler flowmeters (LDF), which detect pulp blood flow, represent an alternative to established pulp tests that stimulate neural activity and require a patient’s response. Young teeth that have been traumatized have had their pulp status investigated by LDF. These teeth have large pulps and are often unrestored. It is more challenging to determine the status of an older, receded pulp, or the pulp of a restored tooth (2). Teeth with caries into dentine and molars have received little attention, but as a result of disease and the cumulative effects of restorations, posterior
2
(Sadly deceased).
© 2014 John Wiley & Sons Ltd
dentine caries. A lingual position alone was effective for 20 teeth (16%). Caries affected light transmission, but for over half the teeth, the pulp could be illuminated from all four probe positions. No effect was found when the influence of mesial and distal restorations on transmission into the corresponding tooth section was examined. The pulp spaces of most (84%) restored, and carious posterior teeth could be illuminated by laser light from their buccal aspect and these teeth could potentially be vitality tested using LDF. KEYWORDS: endodontic diagnosis, laser Doppler flowmetry, molars Accepted for publication 23 March 2014
teeth provide a diagnostic challenge. First molars account for about one-third of teeth requiring root canal treatment (3, 4). The aim of this study was to investigate restored and carious first and second molar teeth to determine how readily their pulp spaces could be illuminated for potential LDF diagnosis.
Materials and methods One hundred and twenty-two extracted first and second molar teeth from patients aged 20–60 years were collected by three private dentists who were not part of the research group. The teeth had to be potentially conservable in the opinion of the practitioner, but extensive coronal restoration and possibly root canal treatment would have been required. In all cases, the patients had opted for extraction following ethical doi: 10.1111/joor.12173
LASER LIGHT TRANSMISSION IN DISEASED MOLARS consent. The patient’s age was noted and the teeth stored in formalin and kept well hydrated throughout the experiment. Inclusion criteria required some coronal tissue remaining and no previous root canal intervention. Of the 122 teeth, 66 were first molars and 56 second molars. The patterns of restoration and caries were very variable. Ninety-five teeth were restored, and of these, 23 had carious dentine present. Forty-three teeth, mainly first molars, had MOD restorations and 32 teeth either an MO or DO restoration. Twenty-nine teeth had dentine caries on one proximal surface, and two had lesions on both surfaces. Four teeth had occlusal caries. Eight teeth, mostly second molars, were restoration and caries-free having lost cusps or restorations. The teeth were cut into two sections axio-buccolingually half way between the mesial and distal contact points using a diamond wafering saw with a blade 020 mm thick; this had been shown previously to reduce mesio-distal length by a mean of 027 mm. Four observations of laser light passage into the buccal and lingual sides of the sections were made: two of the mesial tooth section (B1 and L1) and two of the distal section (B2 and L2) (Fig. 1). A gun sight was used as the laser source (Beamshot 1000S*) with wavelength 630–680 nm and a maximum output
Oral Rehabilitation
Journal of Oral Rehabilitation 2014 41; 630--634
Laser light passage through restored and carious posterior teeth N. P. CHANDLER*, T. R. PITT FORD*2 & B. D. MONTEITH†
*The Sir John Walsh Research
Institute, School of Dentistry, University of Otago, Dunedin, New Zealand and †Department of Conservative Dentistry, Dental Institute, King’s College London, London, UK
Laser Doppler flowmetry (LDF) has been used to investigate pulpal blood flow as a means of pulp vitality testing. Transmission of laser light from the tooth surface to the pulp space may be influenced by caries and restorations. One hundred and twenty-two first and second molars that had caries into dentine, restorations or significant loss of coronal tissue were sectioned in half axiobucco-lingually. The two sections were illuminated with a laser from their buccal and lingual aspects 2 mm coronal to the amelocemental junction. Light reaching the pulp space was recorded. Buccal and lingual illumination sites were equally effective for 67 teeth (55%). Buccal sites alone were effective for 35 teeth (29%), despite over one-third of these surfaces being restored or featuring enamel or SUMMARY
Introduction Diagnosis of pulp disease may be problematic (1). Laser Doppler flowmeters (LDF), which detect pulp blood flow, represent an alternative to established pulp tests that stimulate neural activity and require a patient’s response. Young teeth that have been traumatized have had their pulp status investigated by LDF. These teeth have large pulps and are often unrestored. It is more challenging to determine the status of an older, receded pulp, or the pulp of a restored tooth (2). Teeth with caries into dentine and molars have received little attention, but as a result of disease and the cumulative effects of restorations, posterior
2
(Sadly deceased).
© 2014 John Wiley & Sons Ltd
dentine caries. A lingual position alone was effective for 20 teeth (16%). Caries affected light transmission, but for over half the teeth, the pulp could be illuminated from all four probe positions. No effect was found when the influence of mesial and distal restorations on transmission into the corresponding tooth section was examined. The pulp spaces of most (84%) restored, and carious posterior teeth could be illuminated by laser light from their buccal aspect and these teeth could potentially be vitality tested using LDF. KEYWORDS: endodontic diagnosis, laser Doppler flowmetry, molars Accepted for publication 23 March 2014
teeth provide a diagnostic challenge. First molars account for about one-third of teeth requiring root canal treatment (3, 4). The aim of this study was to investigate restored and carious first and second molar teeth to determine how readily their pulp spaces could be illuminated for potential LDF diagnosis.
Materials and methods One hundred and twenty-two extracted first and second molar teeth from patients aged 20–60 years were collected by three private dentists who were not part of the research group. The teeth had to be potentially conservable in the opinion of the practitioner, but extensive coronal restoration and possibly root canal treatment would have been required. In all cases, the patients had opted for extraction following ethical doi: 10.1111/joor.12173
LASER LIGHT TRANSMISSION IN DISEASED MOLARS consent. The patient’s age was noted and the teeth stored in formalin and kept well hydrated throughout the experiment. Inclusion criteria required some coronal tissue remaining and no previous root canal intervention. Of the 122 teeth, 66 were first molars and 56 second molars. The patterns of restoration and caries were very variable. Ninety-five teeth were restored, and of these, 23 had carious dentine present. Forty-three teeth, mainly first molars, had MOD restorations and 32 teeth either an MO or DO restoration. Twenty-nine teeth had dentine caries on one proximal surface, and two had lesions on both surfaces. Four teeth had occlusal caries. Eight teeth, mostly second molars, were restoration and caries-free having lost cusps or restorations. The teeth were cut into two sections axio-buccolingually half way between the mesial and distal contact points using a diamond wafering saw with a blade 020 mm thick; this had been shown previously to reduce mesio-distal length by a mean of 027 mm. Four observations of laser light passage into the buccal and lingual sides of the sections were made: two of the mesial tooth section (B1 and L1) and two of the distal section (B2 and L2) (Fig. 1). A gun sight was used as the laser source (Beamshot 1000S*) with wavelength 630–680 nm and a maximum output
