Thermal increase in the oral mucosa and in the jawbone during Nd:YAG laser applications. Ex vivo study

Objective: Literature reports bactericidal and biostimulant effects for Nd:YAG laser procedures on bone and oral mucosa but the possible overheating can cause damage to anatomical structures. The aim of the study is the evaluation of thermal increase in different levels of oral tissues: mucosa, periosteum and bone during defocused application of Nd:YAG laser at different parameters. Study Design: Superficial thermal evaluation was performed in pig jaws with a thermal camera device; deep thermal evaluation was realized by 4 thermocouples placed at a subperiosteal level and at 1,2 and 4 mm depth in the jaw bone. Laser applications of 1 minute were performed 5 times (with a pause of 1 minute) on a surface of 4 cm 2 with a Nd:YAG laser (VSP mode, 320 micrometer fiber, defocused mode) with different parameters. Temperatures were recorded before and after laser applications and after each pause in order to evaluate also the thermal relaxation of tissues. Results: At submucosal level, mean thermal increase was between 1.1°C and 13.2°C, at 1 mm depth between 1.1°C and 8.5°C, at 2 mm depth between 1.1°C and 6.8°C, at 4 mm depth between 1.0°C and 5.3°C. Temperature decrease during the rest time period was variable between 0°C and 2.5°C. Conclusions: Temperatures reached during clinical procedures with parameters reported in the literature in biostimulation protocols (1.25-2 Watts) for the five minutes of application are not dangerous for biological structures. The decrease in temperature during the rest time period is less considerable in the bone in comparison to oral mucosa

Surgical Approach and Laser Applications in BRONJ Osteoporotic and Cancer Patients

Bisphosphonates-related Osteonecrosis of the Jaw (BRONJ) has been reported with increasing frequency in literature over last years, but its therapy is still a dilemma. One hundred ninety patients affected by BRONJ were observed between January 2004 and November 2011 and 166 treated sites were subdivided in five groups on the basis of the therapeutical approach (medical or surgical, traditional or laser-assisted approach, with or without Low Level Laser Therapy (LLLT)). Clinical success has been defined for each treatment performed as clinical improvement or complete mucosal healing. Combination of antibiotic therapy, conservative surgery performed with Er:YAG laser and LLLT applications showed best results for cancer and noncancer patients. Nonsurgical approach performed on 69 sites induced an improvement in 35 sites (50.7%) and the complete healing in 19 sites (27.5%), while surgical approach on 97 sites induced an improvement in 84 sites (86.6%) and the complete healing in 78 sites (80.41%). Improvement and healing were recorded in 31 (81.5%) and 27 (71.5%) out of the 38 BRONJ sites treated in noncancer patients and in 88 (68.75%) and in 69 (53.9%) out of the 128 in cancer patients

Case series of 589 tooth extractions in patients under bisphosphonates therapy. Proposal of a clinical protocol supported by Nd: YAG low-level laser therapy

Objective: Trauma during dental surgery is a predisposing factor for bisphosphonates (BP)-related osteonecrosis of the jaws (BRONJ). However, about 40% of cases of BRONJ are not related to dental invasive procedures, be ing probably associated to endodontic or periodontal infections. Extraction of non-treatable teeth is considered a reliable choice, to improve symptoms and to reduce the risk of BRONJ. Here we report our experience of tooth extractions in patients under oral or intravenous BP therapy. Study Design: Two-hundred and seventeen patients (38 males, 179 females; mean age 68.72 ± 11.26 years, range 30 to 83 years) under BP therapy received 589 tooth extractions at the Unit of Oral Medicine, Pathology and Laser-assisted Surgery of the University of Parma, Italy, between June 2006 and December 2010. Ninety five patients were under BP therapy for oncological disease (multiple myeloma (MM): 23; bone metastases (BM): 72) and 122 patients for non oncological diseases: 119 osteoporosis (OP), 2 rheumatoid arthritis (RA) and 1 Paget's disease (PD). The mean duration of BP was of 35 months. Antibiotic treatment was administered three days before and 2 weeks after tooth extractions. Patients were additionally treated with low level laser therapy (LLLT) through Nd:YAG laser (1064 nm - power 1.25 W; frequency 15 Hz; fibre diameter: 320 µm), 5 application of 1 minute each. Patients were evaluated 3 days and once a week for 2 months after the extractions and every time they received LLLT. Mean follow-up was 15 months (ranging from 4 to 31 months). Results: In a total of 589 extractions (285 mandibular, 304 maxillary) performed, a minimal bone exposure was observed in 5 cases, treated with Er:YAG laser vaporization and than healed. Conclusions: Our experience supports the hypothesis that the association of antibiotic treatment and LLLT can be effective in preventing ONJ after tooth extractions in patients under BPT

Laser Welded versus Resistance Spot Welded Bone Implants: Analysis of the Thermal Increase and Strength

Introduction. The first aim of this “ex vivo split mouth” study was to compare the thermal elevation during the welding process of titanium bars to titanium implants inserted in pig jaws by a thermal camera and two thermocouples. The second aim was to compare the strength of the joints by a traction test with a dynamometer. Materials and Methods. Six pigs’ jaws were used and three implants were placed on each side of them for a total of 36 fixtures. Twelve bars were connected to the abutments (each bar on three implants) by using, on one side, laser welding and, on the other, resistance spot welding. Temperature variations were recorded by thermocouples and by thermal camera while the strength of the welded joint was analyzed by a traction test. Results. For increasing temperature, means were 36.83 and 37.06, standard deviations 1.234 and 1.187, and P value 0.5763 (not significant). For traction test, means were 195.5 and 159.4, standard deviations 2.00 and 2.254, and P value 0.0001 (very significant). Conclusion. Laser welding was demonstrated to be able to connect titanium implant abutments without the risk of thermal increase into the bone and with good results in terms of mechanical strength

Low energy KTP laser in oral soft tissues surgery : a 52 patients clinical study

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. The aim of this study was 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 (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. © Medicina Oral

Conservative Surgical Management of Stage I Bisphosphonate-Related Osteonecrosis of the Jaw

Purpose. To report the efficacy of conservative surgical treatment for stage I bisphosphonate-related osteonecrosis of the jaw (BRONJ). Materials and Methods. This study reports the clinical outcomes of 63 patients treated for BRONJ stage I (according to Ruggiero's staging system) at the Oral Pathology and Laser-Assisted Surgery Unit of the University of Parma between January 2004 and January 2011. Surgical interventions were performed, under local analgesia, in patients unresponsive for a period of six months to noninvasive treatments such as cycles of local or systemic antibacterial therapy combined or not to low level laser therapy, ozone therapy, or Hyperbaric Oxygen Therapy. All interventions were performed after the consultation of oncologist or physician. Results. In our experience, conservative surgical treatment is associated with the highest number of BRONJ healed sites in stage I disease. Complete healing was observed in 92.6% of sites surgically treated. Conclusions. This study confirms that treatment of patients affected by minimal bone exposition, (stage I of BRONJ), through conservative surgical strategies, possibly with laser, may result in a high control of the disease in the long term

Aesthetic Treatment Outcomes of Capillary Hemangioma, Venous Lake, and Venous Malformation of the Lip Using Different Surgical Procedures and Laser Wavelengths (Nd:YAG, Er,Cr:YSGG, CO2, and Diode 980 nm)

Different approaches with different clinical outcomes have been found in treating capillary hemangioma (CH), venous lake (VL), or venous malformations (VM) of the lips. This retrospective study aims to assess scar quality, recurrence rate, and patient satisfaction after different surgeries with different laser wavelengths. A total of 143 patients with CH or VM were included. Nd:YAG laser was used for 47 patients, diode 980 nm laser was used for 32 patients (treatments by transmucosal photo-thermo-coagulation), Er,Cr:YSSG laser was used for 12 patients (treatments by excision), and CO2 laser was used for 52 patients (treatments by photo-vaporization). The Manchester scar scale was used by practitioners to assess the scar quality. The recurrence rate and patients’ satisfaction were noted at different follow-ups during 12 months. Our retrospective study showed that laser-assisted aesthetic treatment of vascular lesions (CH, VL, and VM) of the lips can be considered effective regardless of the wavelength used (Er,Cr:YSGG, CO2, Nd:YAG, and diode 980 nm) or the treatment procedure (transmucosal photo-thermo-coagulation, photo-vaporization, and surgical excision). There was no significant difference in patient and practitioner satisfaction with aesthetic outcome at 6 months follow-up. Furthermore, the treatments of lip vascular lesions performed using Er,Cr:YSGG and CO2 lasers did not show any recurrence during the 12 months of follow-up, while recurrence rates of 11% ± 1.4% and 8% ± 0.9% were seen in the diode and Nd:YAG groups, respectively

Etude des effets du laser à CO2 sur les tissus dentaires et les muqueuses buccales: aspects fondamentaux et applications cliniques

Agrégation de l'enseignement supérieur, Orientation médecineThèse présentée pour l'obtention du grade scientifique d'Agrégé de l'Enseignement Supérieur, Orientation médecineinfo:eu-repo/semantics/nonPublishe

Effet du laser à argon sur l'émail dentaire

Doctorat en sciences médicalesinfo:eu-repo/semantics/nonPublishe

Sterilization potential of the CO2 laser.

To test the sterilizing potential of the CO2 laser, two turbines and 70 stainless steel strips have been prepared. Five microns of suspensions (microbial and salivary) have been set and exposed to the laser beam (20 seconds, power of 5 W). The experiments of sterilization, after drying of the suspension did not show any positive result. When the experiments have been done immediately after deposing the suspension and without letting the latter to dry, the results have been positive and the sterilization complete. These experiments show that the CO2 laser has an important potential of sterilization that deserved to be exploited and developed.SCOPUS: ar.jinfo:eu-repo/semantics/publishe