X-ray Diffraction and Calcium-Phosphorous Analysis of Irradiated Human Teeth

Abstract

An investigation into the effects of radiation on extracted human teeth indicated alterations in crystallinity or calcium-phosphorus ratios.Radiation-induced caries is a common sequela of radiation therapy to the head and neck region. Clinical evidence suggests tlat this is a result of alterations in the quality and qLuantity of saliva resulting from cellular destruction in the salivary glands.1,2The pattern and( rampant onset of radiation-induced caries suggest the possibility of the involvement of other causative factors. WvVieman et al reported that they found no alterations in the solubility or chemistry of tooth structure after radiation.3The present study was done to determine if any changes in crystallinity or calciumphosphorus ratios could be demonstrated in extracted human teeth subjected to radiation. A review of the literatuLre produced no evidence of similar studies using these methods of investigation. Materials and MethodsFour freslhly extracted premolar teeth from the same individual were collected for study. Two of the teeth were used as controls. The other two teeth received a single exposure of 12,000 rads using cobalt-60.One each of the control and test teeth was sectioned and prepared for analysis of calcium-phosphorus ratios with use of the electron probe. Figure 1 shows the six different probe paths used in the analysis. Calciumphosphorus counts were taken at 100-micrometer (Mm) intervals at a probe diameter of 10 [m.Enamel biopsy specimens were obtained

Microradiographic and Microscopic Studies on in situ Induced Initial Caries in Irradiated and Nonirradiated Dental Enamel

“…This is in good agreement with previous publications, where demineralization in irradiated enamel resembled natural caries quite well [Jansma et al, 1993;Kielbassa et al, 1997b,c], or where missing structural changes after irradiation have been reported [Jansma et al, 1988a;Wiemann et al, 1972;Zach, 1976]. Kielbassa/Schendera/Schulte-Mönting However, this is in contrast to earlier reports, which demonstrated either an increased solution rate [Pioch et al, 1991;Rössler et al, 1995b;Tepel et al, 1992] or reduced mineral loss and lesion depths after irradiation [Jansma et al, 1988a;Joyston-Bechal, 1985;Markitziu et al, 1989].…”

Effect of X-Ray Irradiation on the Permeability of Bovine Dental Enamel

“…As mentioned in the introduction neither SEM nor X-ray diffraction brought to light any changes in the crystalline structure of enamel af ter X-ray irradiation [Jansma et al, 1988]. Similar re sults were reported by Zach [1976] and Wiemann et al [1972], who found no chemical or structural changes in enamel subjected to X-ray irradiation treatment us ing X-ray diffraction and dispersion staining proce dures, respectively. Jervoe [1970], however, demon strated changes in the crystalline structure of enamel with X-ray diffraction, but he irradiated at an ex tremely high single experimental dose of 10,000 Gy.…”

“…Earlier studies, using scanning electron micros copy and X-ray diffraction [Zach, 1976;Jansma et al, 1988], did not show any changes in the crystalline structure after irradiation. In view of the above re ports, it was the purpose of this study to investigate possible changes in the permeability of irradiated enamel.…”

Bond strengths of two conventional glass-ionomer cements to irradiated and non-irradiated dentin

“…In summary, it was shown that set GIC materials were not affected by gamma irradiation, as seen from the recorded FTIR spectra of this study. Similarly, neither was the crystallinity nor calcium-phosphorus ratio of dentin altered after gamma irradiation 31) . Taken together, the low bond strength of postirradiated groups (A2, B2) could not be explained by the negative effect of irradiation on dentin or glass ionomer cements.…”

“…However, under radiotherapy conditions, irradiation obviously has only a minor effect on the mechanical properties of dentin 30) . Zach 31) reported that irradiated teeth showed no alterations in crystallinity or calcium-phosphorus ratio. Similarly, White et al 32) also reported that gamma irradiation did not alter the structure nor the function of dentin as determined by permeability, FTIR and UV-Vis-NIR spectroscopy.…”