ISSN:1044-5471    

DOI:10.1089/clm.1999.17.1

年代:1999

数据来源: MAL

摘要:

ABSTRACTObjective:This study was conducted to comparein vitropulp chamber temperature changes induced by conventional curing light and argon laser under common conditions.Summary Background Data:Previousin vitrostudies have shown that impacting the surface of teeth with either an argon laser or conventional curing light causes pulp temperature increases of various degrees.Methods:The sample tooth had a class V composite restoration placed with 2.48-mm distance from the surface of the composite to a Thermister Thermometer. The thermometer was inserted into the cutaway pulp chamber to measure the temperature increase from stabilized room temperature, which was caused by exposure to argon laser or conventional curing light.Results:Temperature increases for the argon laser for the recommended curing time were 3°F or less. The longer the exposure times for either method of curing, the higher the temperature increased.Conclusion:At recommended curing times,in vitropulp chamber temperature increases from laser units were significantly lower than those of the conventional curing lights

ISSN:1044-5471    

DOI:10.1089/clm.1999.17.3

年代:1999

数据来源: MAL

摘要:

ABSTRACTObjective:The purpose of this study was to investigate morphological changes in human enamel and dentin structures irradiated with the use of an Er:YAG laser.Summary Background Data:Despite the high number of research projects concerned with digital applications of lasers, few studies have targeted the effects of Er:YAG laser irradiation on human enamel or dentin structures.Methods:Enamel and dentin surfaces of 40 extracted human teeth were irradiated for 5 seconds with a 2.94 μm wavelength, at an output of 300 mJ. Histological and scanning electron microscope studies were then performed to determine the morphological changes in the enamel and dentin structures of those teeth.Results:The Er:YAG laser beam produced defects without signs of serious thermal damage to enamel or dentin. Undesirable thermal effects such as surface cracking or carbonization were not observed. Histological examinations revealed the presence of a thin basophilic line at the bottom and along the walls of defects in the dentin. These morphological changes were evidence of minimal thermal damage to surrounding tissue.Conclusions:These findings suggest that it is possible to remove the enamel and dentin using Er:YAG laser irradiation with minimal thermal changes. However, the mechanism involved in the ablation of enamel and dentin by Er:YAG laser irradiation has not been clarified in this study. Therefore, more research is necessary before the Er:YAG laser can be used clinically in the future

ISSN:1044-5471    

DOI:10.1089/clm.1999.17.7

年代:1999

数据来源: MAL

摘要:

ABSTRACTObjective:The purpose of thisin vitrostudy was to evaluate the potential use of pulsed CO2laser radiation to remove selectively residues of orthodontic bonding resin that remain after debonding of fixed orthodontic appliances.Summary Background Data:Current techniques used for removal of orthodontic bonding resin after removal of fixed appliances include rotary instruments, debonding pliers, and ultrasonic scalers. These techniques, however, are time-consuming and inefficient, and may damage tooth enamel.Methods:A standardized cylinder of orthodontic bonding resin was bonded to the buccal surfaces of 100 extracted premolar teeth, which were then divided into 10 groups of 10 specimens each. In 9 groups, the resin was ablated using 1 of 9 different laser parameters, while in the remaining control group, the resin was removed with a slow speed tungsten carbide bur. Specimens were evaluated by light microscopy and scanning electron microscopy (SEM) to assess the amount of resin remaining and the extent of the damage to the underlying enamel.Results:The 2 W/100 ms combination was optimal, with a high efficiency of resin removal and the least enamel damage. Higher laser powers increased the extent of enamel damage without enhancing resin removal.Conclusions:This laser technique appears promising, however, further studies of the extent of thermal changes at the level of the dental pulp are necessary to establish more fully the risk-benefit ratio.

ISSN:1044-5471    

DOI:10.1089/clm.1999.17.13

年代:1999

数据来源: MAL

摘要:

ABSTRACTObjective:The morphological and atomic analytical changes of the root canal wall dentin, treated with 38% diamine silver fluoride [Ag(NH3)2F] solution and irradiated by carbon dioxide (CO2) laser at the continuous wave mode were evaluatedin vitro.Summary Background Data:There has been no report on the morphological or atomic analytical changes of the effect of Ag(NH3)2F solution and CO2laser on root canal walls.Methods:Eighty extracted human single-rooted teeth were instrumented using a conventional technique and randomly divided into 8 groups of 10 teeth each. The teeth in group 1 were neither treated with Ag(NH3)2F solution nor lased. Groups 2, 3, and 4 were irradiated by laser at the parameters of 1, 2, and 3 W for 10 seconds, respectively. Group 5 was treated with Ag(NH3)2F solution only. The other 3 groups were treated with Ag(NH3)2F solution and then lased by the same method as groups 2, 3, and 4. After this treatment, 4 specimens each from group 1, 5, and 6 were analyzed by scanning electron microscope-energy dispersive x-ray spectroscopy (SEM-EDX) and other specimens in all groups were examined by scanning electron microscopy (SEM).Results:The smear layer and debris of the control and lased specimens were not completely removed, but the areas of carbonization of evaporation of smear layer and open dentinal tubules were observed on the specimens treated with Ag(NH3)2F and lased at 1 W (group 6). After laser irradiation, the amount of silver on the root canal surfaces was significantly reduced to approximately one-third level on the measurement of SEM-EDX (p<0.01).Conclusion:These results suggest that CO2laser is an effective method to remove or melt smear layer of root canal walls after treatment with 38% Ag(NH3)2F solution if an appropriate parameter is selected.

ISSN:1044-5471    

DOI:10.1089/clm.1999.17.19

年代:1999

数据来源: MAL

摘要:

ABSTRACTObjective:The use of percutaneous laser disc decompression (PLDD) for the treatment of erectile dysfunction caused by herniated disc disease is described.Summary Background Data: Disc herniation is often overlooked as a cause of erectile dysfunction, with few cases reported in the literature.Methods:Two patients with erectile dysfunction were treated with PLDD as outpatients.Results:In addition to the early return of erectile function in both cases, immediate pain relief was achieved in the second case. Follow-up visits confirmed continued normal sexual function and lack of pain.Conclusions:The literature now includes 23 cases well-documented cases of erectile dysfunction caused by spinal cord disc herniation. PLDD is a minimally invasive procedure that that can be used to treat herniation of intervertebral discs, which has been found to cause erectile dysfunction.

ISSN:1044-5471    

DOI:10.1089/clm.1999.17.25

年代:1999

数据来源: MAL

摘要:

ABSTRACTObjective:The semiconductor or laser diode (GaAs, 904 nm) is the most appropriate choice in pain reduction therapy.Summary Background Data: Low-power density laser acts on the prostaglandin (PG) synthesis, increasing the change of PGG2and PGH2into PG12(also called prostacyclin, or epoprostenol). The last is the main product of the arachidonic acid into the endothelial cells and into the smooth muscular cells of vessel walls, that have a vasodilating and anti-inflammatory action.Methods:Treatment was performed on 372 patients (206 women and 166 men) during the period between May 1987 and January 1997. The patients, whose ages ranged from 25 to 70 years, with a mean age of 45 years, suffered from rheumatic, degenerative, and traumatic pathologies as well as cutaneous ulcers. The majority of patients had been seen by orthopedists and rheumatologists and had undergone x-ray examination. All patients had received drug-based treatment and/or physiotherapy with poor results; 5 patients had also been irradiated with He:Ne and CO2lasers. Two-thirds were experiencing acute symptomatic pain, while the others suffered long-term pathology with recurrent crises. We used a pulsed diode laser, GaAs 904 nm wavelength once per day for 5 consecutive days, followed by a 2-day interval. The average number of applications was 12. We irradiated the trigger points, access points to the joint, and striated muscles adjacent to relevant nerve roots.Results:We achieved very good results, especially in cases of symptomatic osteoarthritis of the cervical vertebrae, sport-related injuries, epicondylitis, and cutaneous ulcers, and with cases of osteoarthritis of the coxa.Conclusions:Treatment with 904-nm diode laser has substantially reduced the symptoms as well as improved the quality of life of these patient, ultimately postponing the need for surgery.

ISSN:1044-5471    

DOI:10.1089/clm.1999.17.29

年代:1999

数据来源: MAL

ISSN:1044-5471    

DOI:10.1089/clm.1999.17.35

年代:1999

数据来源: MAL

ISSN:1044-5471    

DOI:10.1089/clm.1999.17.37

年代:1999

数据来源: MAL