Quality assessment of PBM protocols for oral complications in head and neck cancer patients: part 2.

PURPOSE: To investigate the role of photobiomodulation (PBM) in patients undergoing head and neck cancer (HNC) treatment. We focused on the consequences of the main complications, such as quality of life (QoL), analgesia, functional impairment, and nutritional status, as well as on the impact on survival/ recurrences, radiotherapy (RT) interruption, adherence, cost-effectiveness, safety, feasibility, and tolerability. METHODS: An electronic search in PubMed and Scopus databases was performed. Full texts were carefully assessed, and data were assimilated into a tabular form for discussion and consensus among the expert panel. RESULTS: A total of 22 papers were included. Overall, a beneficial effect of PBM was evidenced in the amelioration of QoL, nutritional status, the reduction of pain, and functional impairment. Preventive PBM may reduce the incidence and duration of RT interruptions, potentially contributing to improved cancer treatment outcomes. PBM treatments are safe and recommended for routine use, with the caveat of avoiding direct tumor exposures where feasible. However, it does not appear to impact cancer survivorship/recurrences directly. Despite additional clinical efforts involving routine PBM use, the individual and public health benefits will positively impact oncology care. CONCLUSIONS: Quality of life, pain and functional impairment, nutritional status, and survival may be effectively improved with PBM. Given its established efficacy also in reducing RT interruptions and its safety, feasibility, and tolerability, PBM should be included in the field of supportive cancer care in HNC patients. Improved understanding of PBM mechanisms and precise dose parameters is enabling the generation of more robust, safe, and reproducible protocols; thus, it is imperative to support further clinical implementation as well as both applied and basic science research in this novel field.

Soins bucco-dentaires et épidémie de Coronavirus COVID-19.

The COVID-19 Coronavirus epidemic started in December 2019 in China, and progressed very quickly in France. Its consequences were the implementation of national measures such as the containment of the population, but also a disorganization of the healthcare system, in particular concerning oral care. Indeed, dental procedures produce aerosols which can be loaded with viral particles, and as such, constitute a major contamination route by the virus. At the request of the Conference of Deans of the Faculties of Odontology, the National College of University Dentists in Public Health (CNCDUSP) set up a working group in order to issue recommendations for oral care in the context of the COVID-19 epidemic, given the specific risks faced by practitioners. Considering the lack of awareness of the specifics of dentistry in the medical world and among decision-makers, and given the speed with which national measures to fight the epidemic were implemented, the recommendations of the CNCDUSP had to be drawn up rigorously and quickly before being released to the profession. They take into account epidemiological data related to the virus, the specificities of oral care, and thus propose protective measures for dental surgery professionals.The necessary adaptation of the healthcare system during an epidemic will certainly make it possible to learn lessons from this health crisis.

[Oral care and the Coronavirus COVID-19 epidemic] / Soins bucco-dentaires et épidémie de Coronavirus COVID-19.

The COVID-19 Coronavirus epidemic started in December 2019 in China, and progressed very quickly in France. Its consequences were the implementation of national measures such as the containment of the population, but also a disorganization of the healthcare system, in particular concerning oral care. Indeed, dental procedures produce aerosols which can be loaded with viral particles, and as such, constitute a major contamination route by the virus. At the request of the Conference of Deans of the Faculties of Odontology, the National College of University Dentists in Public Health (CNCDUSP) set up a working group in order to issue recommendations for oral care in the context of the COVID-19 epidemic, given the specific risks faced by practitioners. Considering the lack of awareness of the specifics of dentistry in the medical world and among decision-makers, and given the speed with which national measures to fight the epidemic were implemented, the recommendations of the CNCDUSP had to be drawn up rigorously and quickly before being released to the profession. They take into account epidemiological data related to the virus, the specificities of oral care, and thus propose protective measures for dental surgery professionals.The necessary adaptation of the healthcare system during an epidemic will certainly make it possible to learn lessons from this health crisis.

[Oral care and the Coronavirus COVID-19 epidemic]. / Soins bucco-dentaires et épidémie de Coronavirus COVID-19.

The COVID-19 Coronavirus epidemic started in December 2019 in China, and progressed very quickly in France. Its consequences were the implementation of national measures such as the containment of the population, but also a disorganization of the healthcare system, in particular concerning oral care. Indeed, dental procedures produce aerosols which can be loaded with viral particles, and as such, constitute a major contamination route by the virus. At the request of the Conference of Deans of the Faculties of Odontology, the National College of University Dentists in Public Health (CNCDUSP) set up a working group in order to issue recommendations for oral care in the context of the COVID-19 epidemic, given the specific risks faced by practitioners. Considering the lack of awareness of the specifics of dentistry in the medical world and among decision-makers, and given the speed with which national measures to fight the epidemic were implemented, the recommendations of the CNCDUSP had to be drawn up rigorously and quickly before being released to the profession. They take into account epidemiological data related to the virus, the specificities of oral care, and thus propose protective measures for dental surgery professionals.The necessary adaptation of the healthcare system during an epidemic will certainly make it possible to learn lessons from this health crisis.

Multicenter randomized, double-blind controlled trial to evaluate the efficacy of laser therapy for the treatment of severe oral mucositis induced by chemotherapy in children: laMPO RCT.

OBJECTIVES: To demonstrate the efficacy of laser photobiomodulation (PBM) compared to that of placebo on severe oral mucositis (OM) in pediatric oncology patients. The primary objective was the reduction of OM grade (World Health Organization [WHO] scale) 7 days after starting PBM. Secondary objectives were reduction of pain, analgesic consumption, and incidence of side effects. METHODS: One hundred and one children with WHO grade > 2 chemotherapy-induced OM were enrolled in eight Italian hospitals. Patients were randomized to either PBM or sham treatment for four consecutive days (days +1 to +4). On days +4, +7, and +11, OM grade, pain (following a 0-10 numeric pain rating scale, NRS) and need for analgesics were evaluated by an operator blinded to treatment. RESULTS: Fifty-one patients were allocated to the PBM group, and 50 were allocated to the sham group. In total, 93.7% of PBM patients and 72% of sham patients had OM grade < 3 WHO on day +7 (P = 0.01). A significant reduction of pain was registered on day +7 in the PBM versus sham group (NRS 1 [0-3] vs. 2.5 [1-5], P < 0.006). Reduced use of analgesics was reported in the PBM group, although it was not statistically significant. No significant adverse events attributable to treatment were recorded. CONCLUSIONS: PBM is a safe, feasible, and effective treatment for children affected by chemotherapy-induced OM, as it accelerates mucosal recovery and reduces pain.

The effect of laser therapy on the expression of osteocalcin and osteopontin after tooth extraction in rats treated with zoledronate and dexamethasone.

PURPOSE: Laser therapy has been used for the prevention and management of medication-related ostenecrosis of the jaw (MRONJ). The aim of this paper was to investigate the action of laser therapy on extraction socket healing in rats in conditions at risk for MRONJ, evaluating the expression of markers of bone metabolism. METHODS: Thirty male Sprague-Dawley rats were divided in four groups: control group (C, n = 5), laser group (L, n = 5), treatment group (T, n = 10), and treatment plus laser group (T + L, n = 10). Rats of group T and T + L received zoledronate 0.1 mg/kg and dexamethasone 1 mg/kg every 2 days for 10 weeks. Rats of group C and L were infused with vehicle. After 9 weeks, the left maxillary molars were extracted in all rats. Rats of groups L and T + L received laser therapy (Nd:YAG, 1064 nm, 1.25 W, 15 Hz, 5 min, 14.37 J/cm(2)) in the socket area at days 0, 2, 4, and 6 after surgery. Western blot analysis was performed to evaluate the alveolar expression of osteopontin (OPN) and osteocalcin (OCN) 8 days after extraction. RESULTS: Rats of groups L and T + L showed a significant higher expression of OCN compared to rats of groups C and T (+348 and +400 %, respectively; P = 0.013 and P = 0.002, respectively). The expression of OPN did not show significant differences among the different groups. CONCLUSIONS: Our findings suggest that laser irradiation after tooth extraction can promote osteoblast differentiation, as demonstrated by the higher expression of OCN. Thus, laser irradiation could be considered a way to improve socket healing in conditions at risk for MRONJ development.

450 nm Blue Laser and Oral Surgery: Preliminary ex vivo Study.

INTRODUCTION: Dental diode lasers were started to be used at the end of the 1990s and were shown to possess several important characteristics, such as small size and low cost, as well as the advantage of optic fibers delivering system. Although only two wavelengths (810 and 980 nm) had been the most used dental diode lasers, a wavelength emitting in the blue portion of the spectrum has recently been proposed. AIM: The aim of this ex vivo study was to compare the effectiveness of five different fiber-delivered laser wavelengths (450, 532, 808, 1064, and 1340 nm) in the oral soft tissue ablation. MATERIALS AND METHODS: Specimens were surgically collected from the dorsal surface of four bovine tongues and, while deep thermal increase was measured by two thermocouples at 0.5 and 2 mm depth, surface temperature was recorded by an infrared thermometer. Subsequently, specimens were fixed in 10% buffered formalin solution, cut into slices, and embedded in paraffin blocks, and a pathologist made a morphological analysis by optic microscope assigning a score based on the quality of the cut and tissue damage. RESULTS: The analysis showed the best quality of the cut and the lowest temperature increase on the specimens obtained with the shortest laser wavelength (450 nm). CONCLUSION: Even considering this as preliminary study, the use of 450 nm blue diode laser in oral surgery may be suggested to the clinician in their daily practice. CLINICAL SIGNIFICANCE: This study opens a new perspective in oral surgery. Blue diode laser has demonstrated a good quality of the cut with a low energy causing a minimal thermal damage to the tissue, promising a better comfort to patients.

Effects of 915 nm GaAs diode laser on mitochondria of human dermal fibroblasts: analysis with confocal microscopy.

Low-level laser therapy (LLLT) is widely used in tissue regeneration and pain therapy. Mitochondria are supposed to be one of the main cellular targets, due to the presence of cytochrome C oxidase as photo-acceptor. Laser stimulation could influence mitochondria metabolism affecting mainly transmembrane mitochondrial potential (Δψm). The aim of our study is to evaluate "in vitro" the early mitochondrial response after irradiation with a 915 GaAs laser. Since some evidences suggest that cellular response to LLLT can be differently modulated by the mode of irradiation, we would like to evaluate whether there are changes in the mitochondrial potential linked to the use of the laser treatments applied with continuous wave (CW) in respect to those applied with pulsed wave (PW). In this study, we analyzed effects of irradiation with a 915-nm GaAs diode laser on human dermal fibroblast. We compared effects of irradiation applied with either CW or PW at different fluences 45-15-5 J/cm(2) on Δψm. Laser scanning microscopy (LSM) was used in living cells to detect ROS (reactive oxygen species) using calcein AM and real-time changes of and Δψm following distribution of the potentiometric probe tetramethylrhodamine methyl ester (TMRM). At higher doses (45-15 J/cm(2)), fibroblasts showed a dose-dependent decrement of Δψm in either the modalities employed, with higher amplitudes in CW-treated cells. This behavior is transient and not followed by any sign of toxicity, even if reactive oxygen species generation was observed. At 5 J/cm(2), CW irradiation determined a little decrease (5%) of the baseline level of Δψm, while opposite behavior was shown when cells were irradiated with PW, with a 10% increment. Our results suggest that different responses observed at cellular level with low doses of irradiation, could be at the basis of efficacy of LLLT in clinical application, performed with PW rather than CW modalities.

Different laser wavelengths comparison in the second-stage implant surgery: an ex vivo study.

The implant surgery consists of two distinct techniques, the transmucosal, also known as "one-stage" and the "two-stage" technique. Lasers represent a possible aid in implant dentistry, especially in the two-stage technique and its main characteristics are represented by a decreased trauma to bone and soft tissues, a reduction of pain as well as a reduction of the risk of postoperative infections. The aim of this study was to analyze in an animal model the thermal elevation induced by four different laser wavelengths (diode, Nd:YAG, Er:YAG, KTP) during the implant uncovering. Four pig jaws were used to carry out this study. Five implants were placed in each anatomical specimen for a total of 20 fixtures. Four wavelengths (532, 810, 1,064 and 2,940 nm) were used to uncover the implants. Two thermocouples were used to measure temperature changes during laser irradiation at bone level, peri-implant tissues and on the fixture surface The thermocouples were connected with two probes of 1.5 mm in diameter, in order to simultaneously recording two temperature variations. Surface temperature was also checked during all procedures with a thermal camera (Thermovision A 800, Flyr Systems, Stockolm, Sweden) connected to a PC. The mean temperatures of each specimen (five fixtures) were calculated (TM1, mean temperature at the beginning; TM2, mean peak temperature). Furthermore, a record of the temperature at 1 min after the end of the surgical procedure was taken (mean: TM3). All the recorded values were statistically evaluated by one-way analysis of variance (ANOVA). The thermocouples recorded a lower increase in temperature for Er:YAG and KTP laser; Nd:YAG and diode laser produced similar increases characterized by higher values. The thermo-camera pointed out the lower increase for Er:YAG and higher for diode laser. KTP laser resulted faster in uncovering implants and diode laser was the one that needed more time. This ex vivo study showed that laser utilization with the recommended parameters gives no risks of dangerous thermal elevation to the tissues and implants.

Tooth extractions in high-risk patients under bisphosphonate therapy and previously affected with osteonecrosis of the jaws: surgical protocol supported by low-level laser therapy.

Trauma during dental surgery is a predisposing factor for medication-related osteonecrosis of the jaws (MRONJ). There are no specific guidelines for the management of dental extractions in patients under bisphosphonate therapy (BPT). The authors proposed in 2013 a successful protocol for tooth extractions in patients under BPT supported by Nd:YAG low-level laser therapy (LLLT). The aim of this study was to validate the safety and efficacy of this protocol reporting the data related to its application in a particular category of patients under BPT at high risk for MRONJ and who were previously affected with MRONJ. Eighty-two tooth extractions were performed in 36 patients previously affected with MRONJ. Antibiotic treatment was administered 3 days before and 2 weeks after tooth extractions. Patients were additionally treated with Nd:YAG LLLT, 5 applications 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. In a total of 82 extractions, minimal bone exposure was observed in 2 cases, treated with Er:YAG laser vaporization and then completely healed. The data confirmed that laser biostimulation is a reliable technique that can be considered in the surgical protocol for patients under BPT.

Odontogenic myxofibroma: a concise review of the literature with emphasis on the surgical approach.

PURPOSE: The aim of this work is to report a review of the literature concerning epidemiology, clinical and radiographic features as well as treatment of odontogenic myxofibroma (MF). METHODS: The PubMed database was searched using the following keywords: "odontogenic myxofibroma", "odontogenic fibromyxoma", "myxofibroma of the jaw" and "fibromyxoma of the jaw". RESULTS: Fifteen articles reporting the experience with 24 patients were identified. Male/female ratio was 1:1.4 and the average age 29.5 years. The most frequent location was the mandible. In 66.7% of the cases the radiographic appearance was a multilocular radiolucency. Swelling was observed in 13 patients (92.86%), varying degrees of pain in 5 (35.71%) and paresthesia in only one patient (7.14%). Six out of 24 patients (26.09%) were treated with radical surgery and 17 out of 24 (73.91%) with a conservative approach. In two out of 21 cases (9.52%) a recurrence was reported. CONCLUSIONS: MF is an extremely rare tumour and no agreement exist on the causes of its development. According to the present review, the choice of treatment should depend on variables such as localization, presence of a primary or of a recurrent lesion, age, general medical conditions and aesthetic needs of the patient.

Er:YAG 2,940-nm laser fiber in endodontic treatment: a help in removing smear layer.

Cleaning and disinfection of the root canal system are some of the most important goals in endodontic therapy. The aim of this preliminary study is to assess the effectiveness of Er:YAG laser fiber in removing the smear layer produced during root canal walls instrumentation. Forty-eight single-rooted teeth were prepared with manual and rotary Ni-Ti instruments, in addition to 2.5% NaOCl irrigation. Samples were randomly subdivided into groups and treated with: three irradiations of 5 s each, with 300-µm Er:YAG endodontic fiber, 1 W and 2.5% NaOCl solution (A Group); two laser irradiations with 17% EDTA solution and 2.5% NaOCl solution (B Group); laser irradiation plus 17% EDTA solution and 2.5% NaOCl (C Group); only in the final wash of 17% EDTA (control group D). During laser treatment, temperature variations were analyzed by using thermocouple and thermal camera devices in order to test both deep and superficial temperatures. Each sample was finally observed by scanning electron microscope (SEM) at the coronal, medium, and apical thirds at ×500 magnification and blindly scored depending on the amount of smear layer. Statistical analysis of the results was conducted using the Kruskal-Wallis and Mann-Whitney test to determine the eventual significant differences between the quantity of smear layer in each group and between the groups at coronal, medium, and apical third: a p value <0.05 was considered significant. The thermal analysis realized by thermocouple with the used parameters demonstrated that laser endodontic fiber produces an average deep temperature increase of 3.5 ± 0.4 °C; analysis performed with a thermal camera showed an average superficial temperature increase of 1.3 ± 0.2 °C produced by laser endodontic fiber use. Deep and superficial temperatures fall immediately after irradiation possibly without causing structural damage or anatomical alteration inside the root canal and neither on periodontal tissues. SEM analysis showed that specimens of group B had the highest level of cleaning in every third, with a significant difference with groups D and A; group C samples showed a good percentage of cleaned tubules in apical and middle thirds, while group D teeth showed open dentinal tubules in coronal third, with a statistical difference with group A samples which were the worst cleaned. The Er:YAG fiber double irradiation with EDTA 17% and NaOCl 2.5% has been demonstrated to be effective in removing smear layer, even in the apical third which is described as the hardest area to clean during endodontic treatment.

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.

In vitro bactericidal effect of Nd:YAG laser on Actinomyces israelii.

A bactericidal effect has been reported by the use of near-infrared laser light on both Gram-positive and Gram-negative bacteria. The aim of this study was to evaluate the effect of Nd:YAG laser on Actinomyces israelii, filamentous bacteria causing cervicofacial actinomycosis. Experiments were realized on bacterial cells in saline suspension or streaked on Mueller-Hinton (MH) agar plates with or without India ink. Laser application was performed in Eppendorf tubes with different powers and frequencies for 40 s; bacterial suspensions were then streaked on agar plates and incubated at 35 °C in proper conditions for 5 days before colony enumeration. A reduction of colony number variable from 60.13 to 100 % for powers of 2, 4, and 6 W at 25-50 Hz of frequency was observed in comparison with growth control. For agar plates, laser application was performed with different powers at 50 Hz for 60 s. A growth inhibition was observed after 5 days of incubation on MH plates with powers of 6 W and on MH-ink plates with all applied powers. This preliminary study showed a bactericidal effect caused by Nd:YAG laser application worthy to be evaluated in further experiments in vivo.

Laser-assisted surgery with different wavelengths: a preliminary ex vivo study on thermal increase and histological evaluation.

Since the introduction of laser in clinical practice, different wavelengths have been used for oral surgery on the basis of the different characteristics and affinities of each one. The aim of this study was a comparison of different laser wavelengths in relation to both thermal increase and "histological quality" in a model of soft tissue surgery procedures. Thermal evaluation was realized, during laser-assisted surgery excision performed on a bovine tongue, by a thermal camera device to evaluate thermal increase on the surface of the sample and with four thermocouples to evaluate thermal increase on the depth of the specimen; temperature was recorded before starting surgical procedure and at the peak of every excision. The quality of excision, in terms of tissue damage and regularity, was realized by two blind examiners on the basis of established criteria. The highest superficial thermal increase was recorded for Superpulse 5-W CO2 laser, the lowest one for Er:YAG laser. The highest in depth thermal increase was recorded for 5 W Diode laser, the lowest one for Er:YAG laser. The best quality of incision was obtained with a 3-W CO2 laser and 3-W diode laser; epithelial, stromal, and vascular damages were evaluated with different degrees for all the used wavelengths with the best result, in terms of "tissue respect," for Er:YAG laser. In all the surgical procedures performed, thermal increase was evaluated until the end of the procedure; at remaining tissue level, thermal decrease was evaluable in the few seconds after surgery. The Er:YAG laser was the device with a lower influence on thermal increase; CO2 and diode lasers revealed a good histological quality. Further studies may be necessary to test the reliability of laser devices for the excision of all the types of specimens needing histological evaluation and diagnosis.

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, being 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.

Bisphosphonates-related osteonecrosis of the jaws: a concise review of the literature and a report of a single-centre experience with 151 patients.

The osteonecrosis of the jaws (ONJ) is an adverse side effect of long-term bisphosphonate therapy (BPT) firstly described in 2003. The aetiology of BRONJ remains unknown, and the pathogenesis seems multifactorial and related to several local or general factors. Many expert panel developed preventive protocols to facilitate specialists involved in the multidisciplinary management of BRONJ patients. In this paper, we present a concise review of the literature, and we report the experience of the University of Parma with 151 patients that assumed BPT for both oncological (121 patients) and non-oncological (30 patients) diseases. One hundred and thirty-nine BRONJ sites were treated with different approaches (surgical and non-surgical, laser-assisted and non-laser-assisted): in terms of clinical improvement, a statistically significant difference was found between the group treated with the only medical therapy; in terms of complete healing, the introduction in the treatment protocols of both laser-assisted approach and surgical approach improves the therapeutical results.

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 was to evaluate the 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 cm² with a Nd:YAG laser (MSP 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.

Quality Assessment of PBM Protocols for Oral Complications in Head and Neck Cancer Patients: Part 1.

Background: Radiotherapy and chemotherapy are frequently employed in head and neck cancer (HNC) patients causing significant side effects that impair life quality and prognosis. Photobiomodulation (PBM) has become a growing approach to managing such oral complications. Despite its proven efficacy and absence of contraindications, there is still a lack of universally accepted disease-specific PBM protocols. Objective: A narrative review was conducted to identify the current proposals relating to the use of PBM to treat complications of oncological treatments in HNC patients. Methods: An electronic search in PubMed and Scopus databases was performed with the following keywords: ("photobiomodulation" OR "PBM" OR "laser therapy" OR "LLLT" OR "laser") AND ("head and neck cancer" OR "oral cancer") AND ("mucositis" OR "oral mucositis" OR "dysgeusia" OR "oedema" OR "xerostomia" OR "dermatitis" OR "trismus") until October 2021. Results: A total of 35 papers were included in the narrative review. Oral mucositis was the most studied complication, and advisable protocols are conceivable. Although there is a growing interest in PBM to manage of xerostomia, radiodermatitis, pain, and trismus, literature is still scarce to propose a universally feasible protocol. Conclusions: PBM therapy could significantly prevent or reduce the severity of many side effects related to cancer therapies. More research is needed to obtain recommendations over the preferable parameters.