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1.
Transplant Proc ; 49(10): 2305-2309, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29198666

ABSTRACT

BACKGROUND: Our center has used a strategy of pancreas importation owing to long regional waitlist times. Here we assess the clinical outcomes and financial considerations of this strategy. METHODS: This was a retrospective observational cohort study of patients who received a pancreas transplant at Montefiore Medical Center (MMC) from 2014 to 2017 (n = 28). Clinical parameters, including hemoglobin A1c and complications, were analyzed. The cohort was compared with United Network for Organ Sharing (UNOS) Region 9 with the use of the UNOS/Organ Procurement and Transplantation Network database. Cost analysis of length of stay (LOS), standard acquisition (SAC) fees, and transportation was performed with the use of internal financial data. RESULTS: Pancreas importation resulted in significantly shorter simultaneous pancreas kidney transplant waitlist times compared with Region 9: 518 days vs 1001 days (P = .038). In addition, postoperative complications and 1-year HbA1c did not differ between groups: local 6.30% vs import 6.17% (P = .87). Patients receiving local pancreata stayed an average of 9.2 days compared with 11 days for the import group (P = .36). As such, pancreas importation was associated with higher mean charges ($445,968) compared with local pancreas recipients ($325,470). CONCLUSIONS: Long waitlist times in Region 9 have encouraged our center's adoption of pancreas importation to address the needs of our patient population. This practice has resulted in a reduction of waitlist times by an average of 483 days. Understandably, centers have long been wary of importation owing to perceived risk in clinical outcomes. In our single-center experience, we have demonstrated equivalent postoperative glucose control and graft survival. Importantly, there does appear to be increased costs associated with importation, which are mainly driven by LOS. Curiously, importation from regions with lower SAC fees has the potential to offset costs related to transportation expenses. Notwithstanding these findings, pancreas importation does have the potential to lessen the financial societal burden through reduction in waitlist times.


Subject(s)
Health Care Costs/statistics & numerical data , Pancreas Transplantation/economics , Tissue and Organ Procurement/economics , Transplants/economics , Waiting Lists , Adult , Databases, Factual , Female , Glycated Hemoglobin/analysis , Graft Survival , Humans , Kidney Transplantation/economics , Kidney Transplantation/methods , Length of Stay/economics , Male , Middle Aged , Pancreas , Pancreas Transplantation/methods , Retrospective Studies , Tissue and Organ Procurement/methods , Transplants/supply & distribution
2.
Transplant Proc ; 49(8): 1883-1884, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28923642

ABSTRACT

Shprintzen-Goldberg syndrome (SGS) is an autosomal dominant connective tissue disorder. To date, this report is the first account of a successful pancreas transplantation from an SGS donor. The similarity of the outcomes from previous year-on-year pancreas transplantations at the same center demonstrates promising results. Increasing awareness of the utilization of donors with SGS may promote expansion of center-specific criteria for organ acceptance. Therefore, every consideration should be given for use of organs from donors with this genetic abnormality because there is no evidence to suggest poorer allograft viability.


Subject(s)
Arachnodactyly , Craniosynostoses , Marfan Syndrome , Pancreas Transplantation , Tissue Donors , Adolescent , Adult , Blood Glucose/analysis , Diabetes Mellitus, Type 1/surgery , Diabetic Nephropathies/surgery , Female , Humans , Kidney Transplantation , Male
3.
Lasers Med Sci ; 30(8): 2157-64, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26100002

ABSTRACT

The aim of this study was to compare the results, in terms of temperature, colour change and morphology, of two different laser wavelengths with two different concentrations of hydrogen peroxide (HP). The lasers used were KTP (potassium-titanyl-phosphate) laser (λ = 532 nm (PD = 1.98 W/cm2)) and Er:YAG laser (λ = 2940 nm (PD = 2.54 W/cm2)). The bleaching gels used were PolaOffice 35% HP gel and PolaOffice+ 6% HP gel (SDI, Australia). Thirty-six extracted human teeth were selected and divided into two groups. For the 35% HP treatment, 18 teeth were randomly assigned to three subgroups: (1) HP gel without laser irradiation vs. HP gel + KTP laser irradiation; (2) HP gel without laser irradiation vs. HP gel + Er:YAG irradiation; and (3) HP gel + KTP laser irradiation vs. HP gel + Er:YAG irradiation. The same protocol was used for the 6% HP bleaching treatment. The bleaching results were analysed by a spectrophotometer, the thermal elevation by K thermocouples and the enamel surface by a scanning electron microscope (SEM). The Kruskal-Wallis test and the Mann-Whitney test were performed, and the data were analysed using the software StatView and the free Web statistics tool BiostaTGV. The thermal elevation of the Er:YAG groups was higher than KTP, while only the group 35% HP gel vs. 35% HP gel + Er:YAG showed significant colour differences (p < 0.05). SEM photographs showed slight enamel surface morphologic alterations after bleaching treatment. The Er:YAG laser may improve the bleaching results of 35% HP even if it increases the gel temperature, when compared to the KTP laser.


Subject(s)
Hydrogen Peroxide/pharmacology , Lasers, Solid-State , Spectrophotometry/methods , Temperature , Tooth/anatomy & histology , Dental Enamel/drug effects , Dental Enamel/radiation effects , Dental Enamel/ultrastructure , Gels/pharmacology , Humans , Tooth/drug effects , Tooth/radiation effects
4.
Laser Ther ; 24(4): 265-74, 2015 Dec 30.
Article in English | MEDLINE | ID: mdl-26877591

ABSTRACT

BACKGROUND AND AIMS: A 405 nm diode laser is indicated for composite materials polymerizing, thanks to the recent evolution in their compositions, absorbing in blue part of the spectrum. The purpose of this research was to evaluate its performance on two different kinds of composite resins. MATERIALS AND METHODS: Two different composites were polymerized with a traditional halogen lamp, a LED device and a 405 nm diode laser. The depth of the cure, the volumetric shrinkage, and the degree of the conversion (DC%) of the double bond during the curing process were measured. One-way ANOVA test, Kruskal-Wallis tests, and Dunn comparison tests were used for statistic analysis. RESULTS: Regarding the depth of polymerization, the laser had the worst performance on one composite while on the other, no significant difference with the other devices was observed. The volumetric shrinkage showed that laser produced the lowest change in both of the composites. The DC% measure confirmed these findings. CONCLUSIONS: Based on the results of this preliminary study, it is not possible to recommend the 405 nm diode laser for the polymerization of dental composites.

5.
Lasers Med Sci ; 30(3): 1001-6, 2015 Apr.
Article in English | MEDLINE | ID: mdl-24487955

ABSTRACT

The purpose of this study was to perform a preliminary in vitro test on the possible use of two different laser wavelengths, 405 and 532 nm, to improve the dental bleaching results. To perform the test, the degradation of a dye, rhodamine B, under the effects of hydrogen peroxide was used. One hundred and twenty vials were divided into four groups of 30 samples each and, while three of them were irradiated with different wavelengths, 365 nm (reference), 405 nm and 532 nm, the fourth was the non-irradiated control group. Each of the four groups was further divided into three subgroups of 10 cuvettes (n = 10) each. The three subgroups included a group with a rhodamine (RH) solution, a rhodamine and hydrogen peroxide (RH + HP) solution and a rhodamine plus hydrogen peroxide and ferrous gluconate (RH + FR) solution. When hydrogen peroxide was present, only UVA irradiation was able to produce significant results, whereas when the photo-Fenton reaction occurred, all the three wavelengths were able to produce a significant degradation of rhodamine B, with better results for longer wavelengths in comparison with short wavelengths. Within the limitations of this in vitro study, the light of the two laser devices, even remaining less effective than UV activation, showed its ability to improve the performance of bleaching agents based on Fenton photocatalysis, whereas when used in combination with hydrogen peroxide only, the 405-nm laser displayed a small effect and the 532-nm laser produced no effects.


Subject(s)
Lasers, Solid-State , Photobleaching , Tooth Bleaching/methods , Ferrous Compounds/chemistry , Fluorescent Dyes/chemistry , Hydrogen Peroxide/chemistry , Rhodamines/chemistry , Tooth Bleaching Agents/chemistry , Ultraviolet Rays
6.
ScientificWorldJournal ; 2014: 935946, 2014.
Article in English | MEDLINE | ID: mdl-25405238

ABSTRACT

BACKGROUND: The introduction of Er:YAG laser in dentistry for ablation of hard tissues advocated an alternative method of enamel etching for orthodontics purpose. MATERIALS AND METHODS: 55 extracted human third molars were inserted in acrylic resin blocks and divided into five groups of 11 teeth. Group 1 was treated with 37% orthophosphoric acid for 30 seconds. Group 2 was treated with laser irradiation (Er:YAG Fidelius III, Fotona, Slovenia) at 80 mJ and 4 Hz. Group 3 underwent laser treatment (80 mJ, 4 Hz), followed by 37% orthophosphoric acid for 30 seconds. The teeth in Group 4 were treated with laser at 40 mJ and 10 Hz. The teeth in Group 5 were treated with laser (40 mJ, 10 Hz), followed by 37% orthophosphoric acid for 30 seconds. The adhesive remnant index was determined after debonding. RESULTS: Kruskas-Wallis test showed that location parameters (median and mean) are significantly different between Groups 2 and 4 when compared with control group; on the contrary no significant difference was detected between Groups 3 and 5 with the controls. CONCLUSION: The use of Er:YAG laser alone, as in Groups 2 and 4, showed no significant advantages over phosphoric acid in the bonding procedure for orthodontics brackets.


Subject(s)
Acid Etching, Dental/methods , Dental Enamel/drug effects , Molar/drug effects , Phosphoric Acids/pharmacology , Acrylic Resins , Dental Bonding/methods , Dental Enamel/radiation effects , Humans , Lasers, Solid-State , Molar/radiation effects , Molar/surgery , Orthodontic Brackets , Tensile Strength , Tooth Extraction
7.
Transplant Proc ; 46(7): 2406-8, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25242795

ABSTRACT

BACKGROUND: Pulmonary embolism (PE) is an uncommon, life-threatening complication after living donor nephrectomy (LDN), and is considered among the most common causes for donor mortality. Most cases of postoperative PEs are thought to originate in deep venous thrombosis (DVT) of the lower extremities. CASE REPORT: A 56-year-old, healthy woman underwent laparoscopic left LDN. Her postoperative course was complicated by PE, presenting at postoperative day 7. Doppler ultrasonography of her lower extremities did not demonstrate DVT. Both transthoracic echocardiogram and contrast-enhanced computed tomography demonstrated a floating thrombus within the inferior vena cava (IVC) originating from a thrombus in the left renal vein stump. Symptoms resolved with systemic anticoagulation. Repeat transesophageal echocardiography demonstrated resolution of the IVC thrombus. CONCLUSIONS: Thrombus originating in left renal vein stump should be considered in patients who develop PE after LDN, especially when lower extremity DVT is not demonstrated.


Subject(s)
Nephrectomy/adverse effects , Renal Veins , Vena Cava, Inferior , Echocardiography, Transesophageal , Female , Humans , Laparoscopy , Living Donors , Middle Aged , Nephrectomy/methods , Pulmonary Embolism/etiology , Tissue and Organ Harvesting/adverse effects , Tomography, X-Ray Computed , Vena Cava Filters , Venous Thrombosis/diagnosis
8.
Case Rep Dent ; 2012: 487802, 2012.
Article in English | MEDLINE | ID: mdl-22792500

ABSTRACT

Objective. The aim of this study was to assess the ability of Er:YAG laser to remove by excision torus mandibularis and to smooth torus palatinus exostosis. Materials and Methods. Torus mandibularis (TM) and torus palatinus (TP) were surgically eliminated via the Er:YAG laser using the following parameters: TM: output power ranging from 500 to 1000 mJ, frequency from 20 to 30 Hz, sapphire tips (diameter 0.8 mm), air-water spray (ratio 5/5), pulse duration 150 µsec, fluence ranging from 99592 J/cm(2) to 199044,586 J/cm(2). TP: a peeling technique was used to eliminate TP, as excision by slicing being impossible here. Results. TM: excision was obtained after 12730 pulses. TP: smoothing technique took more time compared with excision. Once peeling was considered to be accomplished, the use of a surgical rasp was necessary to eliminate bone spicules that could delay the wound to heal in good conditions. Conclusion. Er:YAG excision (TM) or Er:YAG peeling (TP) are safe clinical techniques easy to practice even if the time required for excision or surface smoothing is more than the time required with bony burs and high speed instruments.

9.
Med Oral Patol Oral Cir Bucal ; 17(2): e287-91, 2012 Mar 01.
Article in English | MEDLINE | ID: mdl-22143694

ABSTRACT

OBJECTIVES: Since 1962 laser appliances have been used for soft tissues surgery of oral cavity with significant advantages compared to the traditional instruments: excellent bleeding control, possibility to avoid the use of suture, good patient compliance thanks to a decrease of intra- and post-operative discomfort and biostimulating effect. Unfortunately, the wavelengths so far used have been seen to cause, in association with an excellent ablation capacity, heat damage of the tissues that can decrease healing process and cause a greater discomfort to patients. To evaluate the laser-assisted KTP laser surgery at low power in terms of characteristics of intervention and patients compliance. STUDY DESIGN: In this study, we describe the application of a new and recently introduced in dentistry wavelength, the KTP laser (532 nm), used with low power parameter (1 Watt - CW), evaluating the time of interventions and, by a Numerical Rating Scale, the intra and postoperative pain. RESULTS: KTP laser used at low power permits to obtain good pain control during operations that were carried out with only a topic anaesthetic (EMLA, Astratech), as shown in VAS tests. Good healing with limited or absent burning areas in treated portion of tissue. CONCLUSIONS: These preliminary study allows us to affirm that KTP laser with low parameters permits to perform oral surgery with good pain control and good wound healing. A greater number of clinical cases are however necessary to confirm the result obtained.


Subject(s)
Lasers, Solid-State/therapeutic use , Mouth/surgery , Oral Surgical Procedures/methods , Female , Humans , Male , Young Adult
10.
Lasers Med Sci ; 25(4): 473-7, 2010 Jul.
Article in English | MEDLINE | ID: mdl-19322623

ABSTRACT

The neodymium:yttrium-aluminium-garnet (Nd:YAG) laser is currently used in dental laboratories to weld metals on dental prostheses. Recently, the use of Nd:YAG has been suggested so that dentists themselves can repair broken fixed, removable and orthodontic prostheses by welding metals directly in the mouth. This work aimed to evaluate, through a four k-type thermocouple system on calf jaws, the thermal increase in the biological structures close to the metal parts during laser welding. We put two hemispherical metal plates onto mandibular molars and then laser welded them at three points with a four k-thermocouple system to determine the thermal rise in the pulp chamber, sulcus, root and bone. This procedure was carried out on 12 samples, and the results were processed. The highest values of thermal increase were found in the pulp chamber, 1.5 degrees C; sulcus, 0.7 degrees C; root, 0.3 degrees C; and bone, 0.3 degrees C. This study showed that thermal increases in pulp chamber, sulcus, root and bone were biologically compatible and that intra-oral laser welding, at the parameters used in this work, seems to be harmless to the biological structures close to the welding and thermally affected zones.


Subject(s)
Dental Soldering/methods , Lasers, Solid-State , Animals , Bone and Bones/physiology , Cattle , Dental Pulp Cavity/physiology , Hot Temperature , In Vitro Techniques , Tooth/physiology
11.
Rev Belge Med Dent (1984) ; 64(3): 108-13, 2009.
Article in French | MEDLINE | ID: mdl-19994545

ABSTRACT

Vestibular deepening for maxillary edentulous patients is mainly indicated once instability cannot be reached due to important bone resorption. Vestibular deepening with CO2 super-pulsed laser enhance, in a bloodless environment, sustentation as well retention of those full dentures in good operative conditions as compared with conventional techniques.


Subject(s)
Jaw, Edentulous/surgery , Laser Therapy , Lasers, Gas/therapeutic use , Maxilla/surgery , Oral Surgical Procedures, Preprosthetic/methods , Vestibuloplasty/instrumentation , Aged , Denture, Complete, Upper , Female , Humans , Jaw, Edentulous/rehabilitation , Male
12.
Eur J Paediatr Dent ; 10(2): 75-82, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19566373

ABSTRACT

AIM: The aim of this study was to observe dentine and enamel surfaces of deciduous teeth under SEM after cavity preparation with Er:YAG laser using different fluences. The results showed that when using Er:YAG laser for cavity preparation in deciduous teeth, no carbonisation or cracks were observed on the enamel and dentine surfaces using energy output between 150-250 Mj, and frequency 15 Hz. The SEM images of the dentine and enamel surfaces were similar to previous studies on permanent teeth: enamel with a typical "lava flow" appearance as a result of an open core of the prism that has lost its typical hexagonal aspect and the dentine with opened tubules plus a difference in the mineral thickness between peritubular and intertubular. CONCLUSION: The difference between the SEM images of deciduous enamel and dentine when using three different energies (150-200-250 mJ) is not significant in order to recommend the use of one type of output energy. In addition, the SEM images are similar TO those of permanent teeth.


Subject(s)
Dental Enamel/ultrastructure , Dentin/ultrastructure , Laser Therapy , Microscopy, Electron, Scanning/methods , Tooth, Deciduous/ultrastructure , Humans
13.
Transplant Proc ; 41(5): 1687-90, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19545708

ABSTRACT

The inclusion of donor middle hepatic vein (MHV) in right-lobe living-donor grafts and the need for reconstruction of the MHV tributaries have long been controversial areas in living-donor liver transplantation. We report technical details in restoration of venous drainage of the anterior sector (segments V and VIII) of the right lobe of the liver graft using a preserved MHV from the recipient liver, and address the issue of reconstruction of donor MHV tributaries without use of an interposition graft. We review clinical situations in which restoration of outflow drainage of the anterior segment of the liver graft should be considered.


Subject(s)
Hepatic Veins/physiology , Liver Transplantation/methods , Living Donors , Organ Preservation/methods , Adult , Anastomosis, Surgical/methods , Humans , Liver/diagnostic imaging , Male , Middle Aged , Tomography, X-Ray Computed
14.
Lasers Med Sci ; 24(1): 81-5, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18084810

ABSTRACT

The aim of this study was to determine whether it is safe to use photo-activated disinfection (PAD) during root canal treatment without heating the periodontal tissues. Root canals of 30 freshly extracted single-rooted teeth were prepared using ProFiles up to size ISO 40 and then filled with photo-sensitiser: tolonium blue (1.2 mg/l). The 635 nm diode laser was used with the manufacturer's endo-tip. Samples were irradiated for 150 s (output power 100 mW, approximate energy density 106.16 J/cm(2)). Temperatures were recorded at working length on the external root surface. After 150 s of PAD irradiation, the average temperature rise was 0.16 +/- 0.08 degrees C. All values were lower than the 7 degrees C safety level for periodontal injury. It was concluded that, regarding the temperature increase, the use of PAD in root canals could be considered harmless for periodontal tissues.


Subject(s)
Dental Pulp Cavity/radiation effects , Disinfection/methods , Lasers , Humans , In Vitro Techniques , Photosensitizing Agents/pharmacology , Temperature
15.
Transplant Proc ; 40(10): 3541-4, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19100433

ABSTRACT

BACKGROUND: Abdominal wall closure after liver transplantation is not always feasible and may result in increased intra-abdominal pressure along with associated complications. Various temporary closure techniques as well as open wound management have been used to address this complex problem. The aim of this series was to describe an approach to definitive wound closure of the open abdomen in liver transplant patients. METHODS: We performed a retrospective review of all liver transplant patients at our institution from September 2005 to November 2007. The management of the open abdomen in 10 liver transplant patients was reviewed, and a novel approach described to manage these defects. RESULTS: Ten patients with open wounds were closed during the study period using human acellular dermal matrix (HADM). There were 7 men and 3 women of median age 55 years. Average size of HADM was 235 cm(2). The median follow-up is 10 months with no incidence of evisceration or hernia. In 1 patient, the graft failed along the lateral side due to infection; it dislodged during vacuum-assisted closure dressing change in another patient at 5 months after closure. Fascial closure was not possible due to organ edema (n = 3), a large liver (n = 4) or wound infection with dehiscence (n = 3). CONCLUSIONS: HADM can be used for primary wound closure in both clean and contaminated wounds as an alternative to an open abdomen post-liver transplantation.


Subject(s)
Abdomen/surgery , Dermatologic Surgical Procedures , Liver Transplantation/methods , Skin/anatomy & histology , Abdominal Cavity/anatomy & histology , Abdominal Wall/anatomy & histology , Adult , Aged , Body Weight , Female , Humans , Male , Middle Aged , Plastic Surgery Procedures/methods , Retrospective Studies , Wound Healing
16.
Eur J Paediatr Dent ; 9(2): 81-7, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18605890

ABSTRACT

AIM: The Er:YAG laser has proven to be effective and efficient in dental hard tissue ablation. The Minimally Invasive Dentistry (MID) approach in caries removal is to stop the disease process and to restore lost tooth structure and function, maximizing the health potential of the tooth. One of the most important concepts of the MID is to preserve as much as possible the dental tissue and this approach is even more important in primary dentition where the dimensions of the crown are smaller and the dimension of the pulp chamber is bigger in relationship to the crown. After treating 30 children's teeth (primary molars and first permanent molars) with the Er:YAG laser, we come to conclusion that laser treatment possesses the requirements of Minimal Invasive Dentistry: the possibility to ablate small area of infected layer guarantees maximum conservation of the tooth structure; using the antibacterial property of the Er:YAG laser we can decontaminate the affected layer that retains its remineralising potential; the lack of smear layer after vaporization with laser assures a better retention of the composite resin to the dentine; preparing the enamel surface with laser before etching gives a better marginal seal of the composite restoration.


Subject(s)
Dental Caries/surgery , Dental Cavity Preparation/instrumentation , Lasers, Solid-State/therapeutic use , Child , Child, Preschool , Humans , Minimally Invasive Surgical Procedures
17.
Photomed Laser Surg ; 25(5): 381-92, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17975951

ABSTRACT

OBJECTIVE: The aim of this clinical study was to observe and evaluate the surgical management efficiency of soft tissues during orthodontic treatment. MATERIALS AND METHODS: Thirty-seven young patients were selected and treated by laser-assisted surgery before or during orthodontic treatment and were classified by sex, age, and type of surgical management. Three different wavelengths were used (diode 810 nm, diode 980 nm, and Nd:YAG 1064 nm) in different surgical situations: maxillary vestibular and lingual frenectomies, surgical exposure and alignment of ectopic or retained teeth, and re-contouring gingival overgrowth. RESULTS: In all evaluated patients, the laser treatment was performed without local anesthesia or sutures. Only topical anesthetic was needed. CONCLUSION: These use of these wavelengths of laser energy was a noticeable aid in the surgical management of soft tissues before or during orthodontic treatment. The benefits of laser treatment include reduced bleeding during surgery with consequent reduced operating time and rapid postoperative hemostasis, thus eliminating the need for sutures. The lack of need for anesthetics and sutures, as well as improved postoperative comfort and healing, make this technique particularly useful for very young patients.


Subject(s)
Laser Therapy/instrumentation , Lasers, Semiconductor , Lasers, Solid-State , Mouth/surgery , Orthodontics, Corrective , Adolescent , Child , Female , Humans , Male , Periodontal Diseases/surgery , Tooth Diseases/surgery
18.
Lasers Med Sci ; 22(4): 237-44, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17308957

ABSTRACT

The laser is a very attractive tool for joining dental metallic alloys. However, the choice of the setting parameters can hardly influence the welding performances. The aim of this research was to evaluate the impact of several parameters (pulse shaping, pulse frequency, focal spot size...) on the quality of the microstructure. Grade 1 titanium plates have been welded with a pulsed Nd-Yag laser. Suitable power, pulse duration, focal spot size, and flow of argon gas were fixed by the operator. Five different pulse shapes and three pulse frequencies were investigated. Two pulse shapes available on this laser unit were eliminated because they considerably hardened the metal. As the pulse frequency rose, the metal was more and more ejected, and a plasma on the surface of the metal increased the oxygen contamination in the welded area. Frequencies of 1 or 2 Hz are optimum for a dental use. Three pulse shapes can be used for titanium but the rectangular shape gives better results.


Subject(s)
Dentistry/methods , Lasers, Solid-State , Titanium , Welding/instrumentation , Dental Alloys , Dental Casting Technique , Humans , Metallurgy/instrumentation , Metallurgy/methods , Pilot Projects
19.
Photomed Laser Surg ; 23(1): 10-4, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15782025

ABSTRACT

OBJECTIVE: The purpose of this study was to define the optimal irradiation conditions of a KTP laser during root planing treatment. METHODS: The surfaces of 60 single-root human teeth were scaled with conventional instruments before lasing. The pulpal temperature increase was measured by means of one thermocouple placed in the pulp chamber and a second one placed on the root surface at 1 mm from the irradiation site. The influence of variables of coloration by Acid Red 52 (photosensitizer), scanning speed, dentin thickness, and probe position was analyzed for a constant exposure time of 15 sec and 500 mw (spot size diameter, 0.5 mm). The pulpal temperature was below 3 degrees C for the adjustments. RESULTS: The irradiation on one point of root surface had the following results: The application of photosensitizer on the root surface before lasing produced a 50% higher temperature rise within the pulp than in the case without the application of the photosensitizer. The temperature rise in the pulp chamber was below 3 degrees C with the following settings of 500 mw: PW = 10 msec and PRR < 35; or PW= 20 msec and PRR < 20 Hz. On the other hand, for the same irradiation conditions, the temperature rise on the surface of the root was always below 7 degrees C. However, the temperature increase became higher than 7 degrees C (on the surface of the root) in the case of P > 500 mw, PW > 50 msec and PRR > 10 Hz of root surface or a scanning speed of irradiation of 1 mm/sec for a linear irradiation of 4 mm. CONCLUSION: The KTP laser may be used safely without thermal damage to pulp and periodontal tissue with respect to the biologically acceptable previously described parameters.


Subject(s)
Body Temperature/physiology , Dental Pulp/physiology , Lasers , Root Planing , Humans , In Vitro Techniques , Phosphates , Titanium
20.
Lasers Surg Med ; 36(3): 220-4, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15704099

ABSTRACT

BACKGROUND AND OBJECTIVES: The aim of this 6-month in vivo study was to investigate if argon laser irradiation of enamel can increase the retention of fluoride. STUDY DESIGN/MATERIALS AND METHODS: Ninety-eight teeth in 12 patients were randomly divided into three groups: (1) EF group: 40 teeth were only treated with fluoride gel (applied for 5 minutes followed by a 1 minute rinsing with distilled water). (2) EFL group: 40 teeth were treated the same way as in the EF group but they were lased after fluoridation. (3) E group: 18 teeth were kept without any treatment as a control group. In order to quantify the fluoride content in the enamel samples, the teeth were analyzed by proton beam delivered by a tandem accelerator (PIgE, particle induced gamma-ray emission). A low energy density of argon laser beam was used: 10.74 J/cm2 (11 mm of beam diameter, irradiation time of 30 seconds, and an output power of 340 mW in continuous mode). RESULTS: The results after 6 months showed that the lased enamel still retained 52.55+/-8.47 ppm or 14.12% of fluoride after the fluoridation process, whereas the unlased enamel retained only 12.18+/-6.82 ppm or 3.27% of fluoride. The untreated and control enamel (E group: unlased and without fluoride treatment) had 1.16+/-4.27 ppm value of fluoride. The statistical test (ANOVA tests at 95% level) showed that the difference is significant between the fluoride retention in the group EFL and the group EF 6 months after fluoridation. CONCLUSIONS: The use of argon laser at low energy density (10.74 J/cm2) significantly increased the fluoride retention in lased enamel that had approximately 400 times more fluoride than the unlased enamel. We consider this procedure as an alternative clinical procedure to increase the fluoride content of enamel surface.


Subject(s)
Acidulated Phosphate Fluoride/pharmacokinetics , Dental Enamel/radiation effects , Low-Level Light Therapy , Acidulated Phosphate Fluoride/administration & dosage , Dental Caries/prevention & control , Dental Enamel/metabolism , Follow-Up Studies , Humans
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