OBJECTIVE:This in vivo pilot study investigated the role of argon laser irradiation and combined fluoride and argon laser treatment in accelerated natural caries development in sound enamel surfaces beneath plaque-retentive orthodontic bands.METHOD AND MATERIALS:Five patients (3 female, 2 male, ages 19 to 28 years) requiring tooth extraction prior to orthodontic treatment, participated in the study. Buccal surfaces were treated with either: (1) argon laser (250 mW for 10 seconds, ARGO-MOD); (2) topical fluoride (0.5% fluoride ion, Thera-Flur-N) followed by argon lasing; or (3) no treatment (control). Orthodontic bands with plaque-retentive slots on buccal surfaces were placed on the teeth slated for extraction (n = 14). Following a minimum of 5 weeks of intraoral exposure, the teeth were extracted for laboratory analysis. The teeth underwent serial longitudinal sectioning (12 sections per tooth). The sections were imbibed in water, and lesion depths were determined with each section, using polarized light microscopy. Comparisons were made among treatment groups (analysis of variance, Duncan's multiple range test for paired samples).RESULTS:Mean lesion depths were: 261 +/- 24 microm for the no treatment control group (n = 84 sections); 147 +/- 18 microm for the argon laser group (n = 24 sections); and 99 +/- 12 microm for the fluoride and argon laser group (n = 60 sections). Both the argon laser (44%) and the fluoride and argon laser groups (62%) had significant lesion depth reductions compared to controls. The addition of fluoride treatment prior to argon lasing resulted in a 32% reduction in lesion depth compared to argon laser treatment alone.CONCLUSIONS:Within this clinical pilot study, in vivo natural caries formation was affected significantly by a single exposure to low fluence argon laser irradiation. Topical fluoride treatment in combination with argon lasing provided an even greater degree of resistance against in vivo enamel caries development. A simple technique for reducing the caries susceptibility of enamel may be a clinical reality.

This polarized light (PL) and scanning electron microscopic (SEM) in vitro study investigated the effect of argon laser (AL) and visible light (VL) polymerization on the interfaces between compomer and composite resin restorations and the enamel cavosurfaces. Surface topography by SEM revealed a smooth transition between the restorative materials and adjacent enamel surfaces with no microspaces between the restorations and enamel surfaces. The enamel surfaces showed relatively smooth surface coatings with AL curing, compared with exposure of etched prism endings with VL curing. The restoration-enamel interface by PL showed an intimate relationship between the restorative materials and the cavosurface enamel. No differences were found between AL and VL polymerization.With the restoration-enamel interface by SEM, compomers and composite resins were adapted closely to the cavosurface enamel and tags of restorative material protruded into the adjacent cavosurface enamel. Both VL and AL polymerization of compomers and composite resin restorations in vitro produced closely adapted restorations with intimate restorationenamel interfaces. Such restoration-enamel interfaces may provide a certain degree of resistance against secondary caries formation, and this may be enhanced by the caries protective effect of argon laser irradiation.

PURPOSE:The purpose of this descriptive scanning electron microscopic study was to characterize surface alterations in primary tooth enamel after in vitro argon laser irradiation alone and combined with topical fluoride treatment either before or after argon laser irradiation.METHODS:Twenty extracted or exfoliated primary teeth underwent soft tissue debridement and a fluoride-free prophylaxis. Buccal and lingual surfaces were determined to be caries-free by macroscopic examination (stereo-zoom binocular microscope, x16). Treatment groups were: (1) no-treatment control; (2) argon laser irradiation (ALI; 11.5 J/cm2); (3) 1.23% acidulated phosphate fluoride (APF before ALI); and (4) ALI before APF. Both buccal and lingual surfaces were evaluated following standard scanning electron microscopic preparation techniques.RESULTS:With controls, enamel surfaces were relatively smooth with occasional enamel prism ends present on their surfaces. There were no areas with cavitations or surface defects. With ALI, the lased surfaces were roughened mildly to moderately irregular without cavitation of the enamel or exposure of enamel prism ends. The surfaces possessed adherent granules to globules, with most being <3 microm in greatest dimension. Only occasional fine cracks and porosities in the surface coatings were noted and these were typically less than 1 microm in width or diameter. With APF before ALI, the surfaces possessed an irregular contour, with numerous granules to globules varying in size from 1 to 3 microm in greatest dimension. With ALI before APF, a homogenous confluent surface was present that masked typical enamel surface markings. The previously noted adherent granules and globules with argon laser treatment alone or APF before ALI were not seen. The argon laser effects on the enamel surfaces were masked by the uniformity of these surface coatings.CONCLUSIONS:Argon laser irradiation and combined APF and argon laser treatment of primary tooth enamel created surfaces that may provide a protective barrier against a cariogenic attack. The surface coatings associated with combined APF and argon laser treatment may contain fluoride-rich calcium and phosphate mineral phases that could act as reservoirs for fluoride, calcium, and phosphate and provide a certain degree of protection from a caries lesion challenge.

Objective: The purpose of this in vitro laboratory study was to determine the effect of low-fluence argon laser (AL) irradiation delivered from two different argon laser systems on enamel caries-like lesion initiation and progression. Background Data: Previous in vitro investigations and a recent in vivo pilot study have shown that AL irradiation of enamel provided a protective effect against in vitro and in vivo cariogenic challenges. Materials and Methods: Twenty extracted human molars were selected, and 10 teeth were assigned to the HGM argon laser group and 10 were assigned to the LaserMed argon laser group. The exposed buccal windows of sound enamel were exposed to low-fluence irradiation, while the lingual windows of enamel were not exposed to laser irradiation and served as the no-treatment (control) group. Enamel caries-like lesions were created using an acidified gel. Two longitudinal sections were taken per sample (n = 20 lesions per group) and evaluated by polarized light microscopy for body of the lesion depths after lesion initiation (8 weeks) and progression (12 weeks) periods. Results: After lesion initiation and progression, the body of lesion depths were similar for both argon-irradiated groups (p > 0.05). With the no-treatment (control) group, there were significant increases in lesion depth with a 61-78% increase for the lesion initiation period and a 50-69% increase for the lesion progression period when compared with the argon laser-treated groups. Conclusion: Argon laser irradiation provides a certain degree of protection against in vitro enamel caries initiation and progression. Resistance to a continuous caries challenge was similar with either argon laser delivery systems (HGM and LaserMed). Argon laser irradiation may prove to be beneficial in reducing the caries susceptibility of sound enamel and white spot lesions in the clinical environment.

Journal of Clinical Laser Medicine & SurgeryVol. 17, No. 4 A Tribute to the Late Dr. Richard J. BlankenauG. Lynn PowellG. Lynn PowellSearch for more papers by this authorPublished Online:29 Apr 2009https://doi.org/10.1089/clm.1999.17.iAboutSectionsPDF/EPUB Permissions & CitationsPermissionsDownload CitationsTrack CitationsAdd to favorites Back To Publication ShareShare onFacebookTwitterLinked InRedditEmail "A Tribute to the Late Dr. Richard J. Blankenau." , 17(4), p. iFiguresReferencesRelatedDetails Volume 17Issue 4Jan 1999 To cite this article:G. Lynn Powell.A Tribute to the Late Dr. Richard J. Blankenau.Journal of Clinical Laser Medicine & Surgery.Jan 1999.i-i.http://doi.org/10.1089/clm.1999.17.iPublished in Volume: 17 Issue 4: April 29, 2009PDF download

Journal of Clinical Laser Medicine & SurgeryVol. 16, No. 6 Editorial: The New Era of Laser DentistryG. Lynn PowellG. Lynn PowellSearch for more papers by this authorPublished Online:29 Apr 2009https://doi.org/10.1089/clm.1998.16.297AboutSectionsPDF/EPUB Permissions & CitationsPermissionsDownload CitationsTrack CitationsAdd to favorites Back To Publication ShareShare onFacebookTwitterLinked InRedditEmail "Editorial: The New Era of Laser Dentistry." , 16(6), p. 297FiguresReferencesRelatedDetails Volume 16Issue 6Dec 1998 To cite this article:G. Lynn Powell.Editorial: The New Era of Laser Dentistry.Journal of Clinical Laser Medicine & Surgery.Dec 1998.297-297.http://doi.org/10.1089/clm.1998.16.297Published in Volume: 16 Issue 6: April 29, 2009PDF download