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Photobiomodulation Therapy in the Treatment of Oral Mucositis, Dysphagia, Oral Dryness, Taste Alteration, and Burning Mouth Sensation Due to Cancer Therapy: A Case Series

Authors:
  • Hammoud Hospital University Medical Center, Saida, Lebanon

Abstract and Figures

Oral complications of cancer therapy, such as oral dryness, dysphagia, and taste alteration, are associated with a negative impact in the quality of life of the patients. Few supportive care measures are available for such complications. This case series reveals the effectiveness of the photobiomodulation (PBM) therapy when used in a specific protocol and parameters, in the management of oral complications related to cancer therapy. Dysphagia was measured using the functional outcome swallowing scale for staging oropharyngeal dysphagia (FOSS). Oral mucositis was measured according to the National Cancer Institute scale. The quantity of the whole resting and stimulated saliva was measured in order to assess the oral dryness. In addition, the taste alteration was measured according to a protocol suggested by the International Standards organization (ISO). Sensation of burning mouth was measured using a visual analogue scale. These measurements were made before treatment, during, and at the end of the treatment. Diode laser 635 nm was used in 3 J/cm2. Five sessions interleaved with 24 h breaks were conducted for the dysphagia and oral dryness, and 10 sessions were conducted for the taste alteration and burning mouth sensation. Regardless of the limitations of this case series, PBM can be considered safe, time saving, and a promising approach for the management of the oral complications due to cancer therapy and the quality of life of cancer patients.
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International Journal of
Environmental Research
and Public Health
Case Report
Photobiomodulation Therapy in the Treatment of
Oral Mucositis, Dysphagia, Oral Dryness, Taste
Alteration, and Burning Mouth Sensation Due to
Cancer Therapy: A Case Series
Marwan El Mobadder 1, * , Fadi Farhat 2, Wassim El Mobadder 2and Samir Nammour 1
1Department of Dental Science, Faculty of medicine, University of Liège, 4000 Liège, Belgium;
S.Namour@ulg.ac.be
2
Department of Hematology-Oncology, Hammoud Hospital University Medical Centre, Saida 652, Lebanon;
drfadi.research@gmail.com (F.F.); wmobader@gmail.com (W.E.M.)
*Correspondence: marwan.mobader@gmail.com; Tel.: +961-71-343-767
Received: 19 October 2019; Accepted: 12 November 2019; Published: 15 November 2019


Abstract:
Oral complications of cancer therapy, such as oral dryness, dysphagia, and taste alteration,
are associated with a negative impact in the quality of life of the patients. Few supportive care
measures are available for such complications. This case series reveals the eectiveness of the
photobiomodulation (PBM) therapy when used in a specific protocol and parameters, in the
management of oral complications related to cancer therapy. Dysphagia was measured using
the functional outcome swallowing scale for staging oropharyngeal dysphagia (FOSS). Oral mucositis
was measured according to the National Cancer Institute scale. The quantity of the whole resting and
stimulated saliva was measured in order to assess the oral dryness. In addition, the taste alteration
was measured according to a protocol suggested by the International Standards organization (ISO).
Sensation of burning mouth was measured using a visual analogue scale. These measurements were
made before treatment, during, and at the end of the treatment. Diode laser 635 nm was used in
3 J/cm
2
. Five sessions interleaved with 24 h breaks were conducted for the dysphagia and oral dryness,
and 10 sessions were conducted for the taste alteration and burning mouth sensation. Regardless
of the limitations of this case series, PBM can be considered safe, time saving, and a promising
approach for the management of the oral complications due to cancer therapy and the quality of life
of cancer patients.
Keywords:
cancer complications; dysphagia; dysgeusia; oral dryness; supportive cancer care;
taste alteration
1. Introduction
Photobiomodulation (PBM) therapy (photon and biological modulation) is a therapeutic approach
that modulates biological activity by employing light at red and near-infrared wavelengths [
1
3
].
The North American Association of Laser Therapy (NAALT) and the World Association of Laser
Therapy (WALT) reached a consensus in 2014 on the nomenclature of photobiomodulation (PBM) as
the therapeutic use of light [
4
,
5
]. The first evidence of the biostimulation eect of the lasers dates back
to 1967 in an experiment by Andre Mester [
6
]. In recent years, the application of PBM has moved on
rapidly due to the combination of a better understanding of the technical, clinical, and photobiological
principles of the use of red and infrared light [
7
]. At present, a great number of studies suggest that
PBM significantly reduces inflammation process, reduces pain, prevents fibrosis, and enhances wound
healing and tissue regeneration [
7
,
8
]. Although there is a surfeit of studies evidencing that PBM
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Int. J. Environ. Res. Public Health 2019,16, 4505 2 of 11
eectively modifies biological functions, the complex biologic mechanism PBM exerts its therapeutic
eects with has not been fully understood, where it varies according to dierent tissue states, cell type,
irradiation parameters, and other factors [9]. PBM was shown to act primarily by increasing the ATP
production and causing a short burst of reactive oxygen species (ROS) [
10
]. The most acceptable theory
is that cytochrome c oxidase (CcO) by the red and infrared light will cause an increase in the ATP
production [
10
12
]. In addition, recent studies have suggested that PBM may activate transcription
factors and signaling pathways and may have a protective mechanism [1012].
It is confirmed in literature that chemotherapy (CT) and/or head and neck radiation therapy
(HNRT) can have tremendous negative impact on the quality of life of the patients and can largely
aect their adherence to the treatment [
13
,
14
]. One of the most common oral complication known
due to cancer therapy is the inflammation of the oral mucosa defined as oral mucositis (OM) [
15
,
16
].
The national cancer institute (NCI) defines oral mucositis as an acute inflammation and/or ulceration
of the oral or oropharyngeal mucosal membranes. It can cause pain/discomfort; interfere with eating,
swallowing, and speech; and may lead to infection. The severity of OM can vary from discomfort
from erythema and soreness to severe ulcers that make alimentation impossible [
15
,
16
]. In addition to
the oral mucositis, patients experience significant alteration in swallowing (dysphagia), alterations in
taste perception (dysgeusia), hyposalivation, oral dryness, osteonecrosis of the jaw, trismus, speech
alteration, as well as chronic pain [
17
19
]. According to the World Gastroenterology Organization
(WGO), dysphagia refers either to the diculty someone may have with the initial phases of a swallow
or to the sensation that foods and or liquids are somehow being obstructed in their passage from the
mouth to the stomach.
These oral complications are associated with a high possibility of a negative impact not only on
the quality of life (QoL) but also on the patient’s compliance to therapy and the clinical outcomes;
this is why it is important to prevent and to treat these complications [
19
]. On the other hand, there
are only few available measures to prevent and/or treat these oral complications of cancer therapy,
and to the best of our knowledge, very few investigations studied the use of PBM in the treatment of
dysphagia, oral dryness, and taste alteration due to cancer therapy [20].
The aim of this case series is to assess the eectiveness of photobiomodulation therapy
with a specific protocol that was suggested by a multinational panel of experts in the field of
photobiomodulation and supportive care in cancer patients in the treatment of dysphagia, oral dryness,
taste alteration, and burning mouth sensation [19].
2. Case Reports
2.1. Case 1: Oral Dysphagia and Oral Mucositis
A 59-year-old woman with breast cancer, under Everolimus medication, was brought to the clinic
complaining of a chronic swallowing impairment (dysphagia) and pain sensation with a feeling of
generalized hot oral mucosa. The patient signed a written informed consent before her engagement
in the study. The patient was under 5 mg/day Everolimus (Afinitor) for 2 months. According to
the patient, the symptoms appeared the first month of medication intake and persisted. The clinical
examination revealed the presence of erythema and ulcers, but these did not interfere with the patient’s
diet. According to a meticulous examination of the oral cavity, the patient was diagnosed with oral
mucositis grade II of the national cancer institute scale (NCI) (Table 1). A speech therapy specialist
diagnosed the patient with a chronic dysphagia. The NCI assessment scale for oral mucositis and
the functional outcome swallowing scale for staging oropharyngeal dysphagia (FOSS) (Table 2) [
21
]
were used in order to assess the severity of the complication before the treatment and after 24 h of
each treatment. According to the FOSS scale, the patient showed a compensated abnormal function
manifested by significant dietary modifications and prolonged mealtime with a stable weight and
occasional cough with an absent aspiration—therefore a stage II of the FOSS scale [
21
]. According to
the oral mucositis assessment scale for OM, the patient was diagnosed with a stage 2. The treatment of
Int. J. Environ. Res. Public Health 2019,16, 4505 3 of 11
choice was the therapeutic use of photobiomodulation therapy. For the management of oral mucositis,
diode laser 635 nm (smart M Pro, Lasotoronix, Poland) was intraorally applied at energy density of 3
J/point and a time of 30 s, output power of 100 mW, in a continuous and contact mode on four points on
the tongue and two on the oropharynx (Figure 1). Extraoral application of diode laser was conducted
with a wavelength of 635 nm, energy density of 3 J/point, output power of 100 mW, and a time of
30 s per point on the following areas: Lips, cutaneous surface corresponding to the buccal mucosae,
and bilateral cervical lymphatic chain (Table 3). For the management of dysphagia, the parameters
were as follows: Diode laser 635 nm (smart M Pro, Lasotronix, Poland) 3 J/cm2for 30 s on each point,
output power of 100 mW, continuous and contact mode. One session of PBM was conducted each
24 h for five days. The intraoral irradiated surfaces were bilaterally: Four points on the soft palate
and four points on the oropharynx. The extraoral irradiated surfaces were lateral and ventral pharynx
and larynx, midline neck, and lateral neck anterior to sternocleidomastoid muscle (Table 4). After
treatment, a significant reduction of dysphagia (from stage II to Stage 0) was noted and a significant
reduction of the oral mucositis was noted (Table 5). Therefore, PBM therapy successfully treated the
cancer therapy-induced dysphagia.
Table 1. National Cancer Institute assessment scale for oral mucositis.
Grade Description
Grade 0 (none) None
Grade 1 (mild)
Painless ulcers, erythema, or mild soreness in the absence of lesions
Grade 2 (moderate)
Painful erythema, edema, or ulcers but eating or swallowing possible
Grade 3 (severe) Painful erythema, edema, or ulcers requiring IV hydration.
Grade 4 (life-threatening) Severe ulceration or requiring parenteral or enteral nutritional
support or prophylactic intubation.
Grade 5 (death) Death related to toxicity.
Table 2.
Functional outcome swallowing scale for staging oropharyngeal dysphagia proposed by John
R. Salassa in the 39th annual meeting of the American Society for Head and Neck Surgery.
Stage Stage Criteria
Stage 0 Normal physiological function and asymptomatic.
Stage I
Normal physiological function but with episodic or daily symptoms of
dysphagia such as reflux symptoms, globus, odynophagia, repetitive
swallow, throat-clearing habit, diculty chewing, minor oral
incompetence, sensation of food getting stuck in the throat or esophagus.
Stage II
Compensated abnormal function manifested by significant dietary
modifications or prolonged mealtime. Weight is stable, cough is absent
or occasional, aspiration is absent or occasional and mild.
Stage III
Decompensated abnormal function manifested by weight loss of 10% or
loss of body weight over 6 months due to dysphagia, or frequent cough,
gagging, or aspiration during meals. Aspiration may be mild or
moderate. Patients in this stage are unstable in terms of nutrition or
respiratory status. Pulmonary complications have not occurred, but the
patient is at risk.
Stage IV
Severely decompensated abnormal function manifested by weight loss
of more than 10% of body weight over 6 months due to dysphagia,
or severe aspiration. Non-oral feeding recommended for most (>50%) of
nutrition. Patients in this stage are nearly complete failures at
swallowing and may safely swallow only under strictly defined
conditions, which do not meet their nutritional needs.
Stage V
Nonoral feeding for all nutrition. Patients in this stage are complete
failures at swallowing. They are dierent from stage IV in that they
cannot swallow anything safely.
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Int. J. Environ. Res. Public Health 2019, 16, x 4 of 11
Stage
V
Nonoral feeding for all nutrition. Patients in this stage are complete failures at swallowing. They are
different from stage IV in that they cannot swallow anything safely.
Table 3. Photobiomodulation therapy for the management of oral mucositis parameters: Applications
and treatment protocol.
Irradiation Treatment Area Parameters
Intraoral Four points on the tongue and two on
the oropharynx. Diode laser 635 nm, energy density of 3 J/cm2,
time of 30 s per spot, output power of 100 mW
in a continuous and contact mode.
Extraoral
Lips, cutaneous surface corresponding
to the buccal mucosae, bilateral cervical
lymphatic chain.
Table 4. Photobiomodulation therapy for the management of dysphagia parameters: Applications
and treatment protocol.
Irradiation Treatment Area Pa
r
ameters
Intraoral
Four points on the soft palate, four points on the
oropharynx. Bilaterally, four points to soft palate
and onto oropharynx. Wavelength of 635 nm, 3 J/cm2 for 10 s
on each point, 100 mW, continuous
and contact mode.
Extraoral
Lateral and ventral pharynx and larynx. Midline
neck and lateral neck anterior to
sternocleidomastoid muscle.
Table 5. Results of the assessments of oral mucositis using the national cancer and dysphagia using
the functional outcome swallowing scale for staging oropharyngeal dysphagia.
Assessment method Ti T1 T2 T3 T4 T5
FOSS scale 2 2 1 1 0 0
NCI scale 2 2 1 0 0 0
Ti = before treatment, T1 = after 24 h of the first session, T2 = after 24 h of the second session, T3 = 24
h after the third session, T4 = 24 h after the fourth session, T5 = 24 h after the fifth session, FOSS =
functional outcome swallowing scale for staging oropharyngeal dysphagia, NCI= national cancer
institute. Oral mucositis measurements were made according to the National Cancer Institute.
Figure 1. Photobiomodulation (PBM) treatment area for the management of oral mucositis [19].
2.2. Case 2: Oral Dryness
A 48-year-old male patient diagnosed with adenocarcinoma consistent with salivary duct
carcinoma underwent intensity-modulated radiation therapy for two months and was referred to the
clinic. The patient signed a written informed consent before his engagement in the study. During the
high dose radiation therapy, the patient started to complain of a chronic oral dryness that persisted
over time. According to the patient, the oral dryness persisted with no improvement with time. Based
Figure 1. Photobiomodulation (PBM) treatment area for the management of oral mucositis [19].
Table 3.
Photobiomodulation therapy for the management of oral mucositis parameters: Applications
and treatment protocol.
Irradiation Treatment Area Parameters
Intraoral
Four points on the tongue and two
on the oropharynx. Diode laser 635 nm, energy
density of 3 J/cm2, time of 30 s per
spot, output power of 100 mW in
a continuous and contact mode.
Extraoral
Lips, cutaneous surface
corresponding to the buccal
mucosae, bilateral cervical
lymphatic chain.
Table 4.
Photobiomodulation therapy for the management of dysphagia parameters: Applications and
treatment protocol.
Irradiation Treatment Area Parameters
Intraoral
Four points on the soft palate, four
points on the oropharynx.
Bilaterally, four points to soft
palate and onto oropharynx. Wavelength of 635 nm, 3 J/cm2for
10 s on each point, 100 mW,
continuous and contact mode.
Extraoral
Lateral and ventral pharynx and
larynx. Midline neck and lateral
neck anterior to
sternocleidomastoid muscle.
Table 5.
Results of the assessments of oral mucositis using the national cancer and dysphagia using the
functional outcome swallowing scale for staging oropharyngeal dysphagia.
Assessment Method TiT1 T2 T3 T4 T5
FOSS scale 2 2 1 1 0 0
NCI scale 2 2 1 0 0 0
Ti=before treatment, T1 =after 24 h of the first session, T2 =after 24 h of the second session, T3 =24 h after the third
session, T4 =24 h after the fourth session, T5 =24 h after the fifth session, FOSS =functional outcome swallowing
scale for staging oropharyngeal dysphagia, NCI=national cancer institute. Oral mucositis measurements were
made according to the National Cancer Institute.
2.2. Case 2: Oral Dryness
A 48-year-old male patient diagnosed with adenocarcinoma consistent with salivary duct
carcinoma underwent intensity-modulated radiation therapy for two months and was referred
to the clinic. The patient signed a written informed consent before his engagement in the study. During
the high dose radiation therapy, the patient started to complain of a chronic oral dryness that persisted
over time. According to the patient, the oral dryness persisted with no improvement with time. Based
Int. J. Environ. Res. Public Health 2019,16, 4505 5 of 11
on a meticulous clinical examination, oral dryness due to irritation of the major salivary glands was
diagnosed. The treatment of choice was photobiomodulation therapy each 24 h for five sessions. Diode
laser 635 nm (smart M Pro, Lasotronix, Poland) was used with the following parameters: Energy of
3 J/cm
2
, output power of 100 mW, time of irradiation of 30 s on each point (Figure 2), continuous and
contact mode (Table 6). In order to assess the severity of oral dryness and to measure the impact of
the treatment, quantity of resting and stimulated saliva before and after stimulation was measured.
Expectoration of all saliva into a graduated test tube was conducted for a 10-minute period without
stimulation. After citric acid stimulation, the patient was also invited to expectorate all the saliva for
only 5 min. After 24 h of each session, the measurements of the resting and stimulated saliva were
made. This method used to assess the severity and the variation of oral dryness has been suggested by
a systematic review [
22
]. The quantity of the resting and stimulated saliva increased significantly after
the treatment (Table 7). According to these findings, PBM eectively increases the salivation.
Int. J. Environ. Res. Public Health 2019, 16, x 5 of 11
on a meticulous clinical examination, oral dryness due to irritation of the major salivary glands was
diagnosed. The treatment of choice was photobiomodulation therapy each 24 h for five sessions.
Diode laser 635 nm (smart M Pro, Lasotronix, Poland) was used with the following parameters:
Energy of 3 J/cm2, output power of 100 mW, time of irradiation of 30 s on each point (Figure 2),
continuous and contact mode (Table 6). In order to assess the severity of oral dryness and to measure
the impact of the treatment, quantity of resting and stimulated saliva before and after stimulation
was measured. Expectoration of all saliva into a graduated test tube was conducted for a 10-minute
period without stimulation. After citric acid stimulation, the patient was also invited to expectorate
all the saliva for only 5 min. After 24 h of each session, the measurements of the resting and stimulated
saliva were made. This method used to assess the severity and the variation of oral dryness has been
suggested by a systematic review [22]. The quantity of the resting and stimulated saliva increased
significantly after the treatment (Table 7). According to these findings, PBM effectively increases the
salivation.
Table 6. Photobiomodulation therapy for the management of oral dryness: Parameters and treatment
protocol.
Oral
Complication Treated Area Parameters
Oral dryness
Intraoral application: 10 points on the major
salivary glands: Parotid and submandibular
glands. Minor salivary glands in each side.
10 points on the dorsal aspect of the tongue.
Diode laser 635 nm. Energy density
of 3 J/cm2 for 30 s, output power of 100
mW, continuous and contact mode.
Table 7. Assessment of the quantity of completely resting and stimulated saliva before, during, and
after treatment (Q-sal, mL/min).
Quantity of saliva Ti T1 T2 T3 T4 T5
Before stimulation 0.03 0.03 0.05 0.07 0.12 0.2
After stimulation 0.1 0.15 0.15 0.3 0.3 0.4
Ti = before treatment, T1 = after 24 h of the first session, T2 = after 24 h of the second session, T3 = 24
h after the third session, T4 = 24 h after the fourth session, T5 = 24 h after the fifth session.
Figure 2. PBM treatment area for the management of oral dryness [19]
2.3. Case 3: Taste Alteration Associated with Burning Mouth Sensation
A 42-year-old man underwent intensified head and neck radiotherapy and was referred to the
clinic with a chief complaint of a complete loss of taste function and a sensation of mouth burning.
The patient signed a written informed consent before his engagement in the study. According to a
thorough clinical examination, the diagnosis was a taste alteration due to direct neurological toxicity
of the taste buds cells of the tongue. In order to assess the severity of the taste alteration, the
International Standards Organization (ISO) ISO 3972:2011 for the measurements of taste alteration
was used. Sweet, salty, sour, bitter, and umami were each tasted in a single “sip and spit” technique
after a rinse of the mouth with room-temperature, purified water three times before and after
Figure 2. PBM treatment area for the management of oral dryness [19]
Table 6.
Photobiomodulation therapy for the management of oral dryness: Parameters and
treatment protocol.
Oral Complication Treated Area Parameters
Oral dryness
Intraoral application: 10 points on
the major salivary glands: Parotid
and submandibular glands. Minor
salivary glands in each side.
10 points on the dorsal aspect of
the tongue.
Diode laser 635 nm. Energy
density of 3 J/cm2for 30 s, output
power of 100 mW, continuous and
contact mode.
Table 7.
Assessment of the quantity of completely resting and stimulated saliva before, during, and after
treatment (Q-sal, mL/min).
Quantity of Saliva TiT1 T2 T3 T4 T5
Before stimulation 0.03 0.03 0.05 0.07 0.12 0.2
After stimulation 0.1 0.15 0.15 0.3 0.3 0.4
Ti=before treatment, T1 =after 24 h of the first session, T2 =after 24 h of the second session, T3 =24 h after the
third session, T4 =24 h after the fourth session, T5 =24 h after the fifth session.
2.3. Case 3: Taste Alteration Associated with Burning Mouth Sensation
A 42-year-old man underwent intensified head and neck radiotherapy and was referred to the
clinic with a chief complaint of a complete loss of taste function and a sensation of mouth burning.
The patient signed a written informed consent before his engagement in the study. According to
a thorough clinical examination, the diagnosis was a taste alteration due to direct neurological toxicity of
the taste buds cells of the tongue. In order to assess the severity of the taste alteration, the International
Int. J. Environ. Res. Public Health 2019,16, 4505 6 of 11
Standards Organization (ISO) ISO 3972:2011 for the measurements of taste alteration was used. Sweet,
salty, sour, bitter, and umami were each tasted in a single “sip and spit” technique after a rinse of the
mouth with room-temperature, purified water three times before and after sampling and expectorating
each solution. The solutions and their corresponding concentrations were sucrose 300 mM, NaCl 200
mM, citric acid 5 mM, caeine 10 mM, and monosodium glutamate (MSG) 200 mM. Perceived taste
quality was identified by selecting one of seven choices. Correct responses were sweet for sucrose,
salty for NaCl, sour for citric acid, bitter for caeine and savory for MSG. Further choices were none or
metallic. The score was assigned as 0–5 correct choices—if the patient failed to identify the correct
taste (0) and if the answer was correct (1). Before any examination and data collecting, the patient was
asked to stop eating and to drink only water at least one hour prior to testing. The taste alteration score
was zero out of five before treatment. In addition, in order to assess mouth-burning sensation, visual
analogue scale (VAS) was used where 0 represented no pain at all and 10 represented the greatest
pain. VAS scale was measured before and after 24 h of each treatment (Table 8). PBM therapy was
the treatment of choice. For the management of taste alteration, one session of PBM therapy was
carried out each 24 h for five consecutive days, and the same procedure was repeated after 48 h.
The irradiated areas were 10 points on the dorsum of the tongue, three points on the right lateral of the
tongue, and three points on the left lateral of the tongue (Figure 3). Diode laser 635 nm (smart M Pro,
Lasotronix, Poland) was used with an energy density of 3 J/cm
2
, 30 s of irradiation, output power of
100 mW, continuous and contact mode (Table 9). For the management of burning mouth sensation,
diode laser 635 nm was used with the same previous parameters on the following areas: Three points
on the tongue, four points on the lateral border of the tongue, 10 points on the dorsal surface of the
tongue, eight points on the buccal mucosa, five points on the labial mucosa, eight points on the hard
palate, three points on the soft palate, three points by sextant on the gingiva (Table 9). After PBM
therapy, the taste alteration score was 5/5 (Table 8). According to the results, PBM can be considered as
an eective approach for the management of taste alteration in cancer patient.
Table 8.
Assessment of the quantity of whole resting and stimulated saliva before, during and after
treatment (Q-sal, mL/min).
Assessment Method TiT1 T2 T3 T4 T5 No Treatment
for 48 h T6 T7 T8 T9 T10
ISO 3972: 2011 score for
taste alteration 0 0 1 1 2 2 2 2 4 4 5 5
Visual analogue scale for
burning mouth sensation 7 7 6 6 4 4 4 4 2 1 0
Ti=before treatment, T1 =after 24 h of the first session, T2 =after 24 h of the second session, T3 =24 h after the
third session, T4 =24 h after the fourth session, T5 =24 h after the fifth session
. . .
, T10 =24 h after the 10th session.
Int. J. Environ. Res. Public Health 2019, 16, x 7 of 11
Gingiva: Three points by sextant
Figure 3. PBM treatment area for the management of taste alteration [19].
4. Discussion
In recent years, much knowledge has been gained on the PBM therapy mechanism of action after
a plethora of laboratory, animal, and human studies [23–25]. In fact, over 100 phase III randomized
controlled trials and over 1000 laboratory studies have studied the effects of photobiomodulation in
different branches of medicine [24,25]. The biological modulation due to light therapy is the
conversion of luminous energy to metabolic energy, which will lead to the modulation of cell
functioning, and it happens when the near-infrared and infrared light reaches the targeted tissue.
Photoacceptors, also called chromophores, are molecules found in nearly all living cells that absorb
light energy and cause a change in cell function [26]. Chromophores typically absorb very specific
wavelengths of light and reflect others, and it is the absorption of energy by chromophores during
light irradiation that determines the specific biological responses [26]. Furthermore, it is now
established that PBM acts principally on the chromophore cytochrome c oxidase (CcO) and the
intracellular water. The CcO that is found in the mitochondria is the terminal enzyme of the electron
transport chain, intermediating the electron transfer from cytochrome c to molecular oxygen.
Therefore, CcO is implicated in the ATP production, which means that a stimulation of the CcO will
lead to a stimulation in the ATP production. It was found that CcO acts as a photo-acceptor and
transducer of photo-signals in the red and near-infrared regions of the light spectrum [27]. An
increase in intracellular ATP is one of the most frequent and significant findings after PBM both in
vitro and in vivo. Therefore, the stimulated synthesis of ATP is caused by an increased activity of
CcO when activated by PBM. In addition, photobiomodulation induces a redox effect by stimulating
a short and transient activation of the reactive oxygen species (ROS). Large doses of light, and even
more particularly blue light, leads to the production of ROS, and it is well known that mitochondria
are one of the most important sources of ROS; therefore, the PBM is somehow implicated in the
induction of redox effects. Moreover, PBM is implicated in the activation of transcription factors and
signaling pathways, since many of the secondary mediators of PBM, like the reactive oxygen species,
are able to activate transcription factors and signaling pathways [11].
Acute and chronic oral complication as a side effect of cancer therapy represents a serious clinical
challenge and affects largely the quality of the life of the cancer patients. The fact that
photobiomodulation has shown to be efficient in the curative and preventive management of oral
mucositis has led to a motivation for further studies to apply photobiomodulation therapy in the
other, less frequent, oral complications of cancer therapy [28]. Furthermore, studies are being
conducted on the efficacy of PBM in the reduction of neuropathy symptoms and on the possible
neuro-regenerative effects. A prospective, randomized, placebo-controlled study with seven breast
cancer patients with a chemotherapy-induced peripheral neuropathy assessed the efficacy of PBM.
Based on the study, there seems to be a tendency towards the prevention of chemotherapy-induced
peripheral neuropathy with the photobiomodulation therapy [29]. In addition, a randomized, sham-
controlled clinical trial on 70 patients showed that the chemotherapy-induced peripheral neuropathy
was significantly reduced, there was no significant reduction in the sham group, and that the addition
of physiotherapy had no positive income [30].
In this case series, the oral complications managed were oral mucositis, dysphagia, oral dryness,
taste alteration, and burning mouth sensation. To the extent of our knowledge, there are only few
published studies on PBM for the management of dysphagia, oral dryness, burning mouth sensation,
Figure 3. PBM treatment area for the management of taste alteration [19].
Int. J. Environ. Res. Public Health 2019,16, 4505 7 of 11
Table 9. Photobiomodulation therapy for the management of taste alteration.
Oral Complicatin Zone Irradiated Parameters
Taste alteration
10 points on the dorsum of the tongue
Three points on the right lateral
Three points on the left lateral aspect
of the tongue Diode laser 635 nm.
Energy density of 3 J/cm2for 30 s,
output power of 100 mW,
continuous mode
contact mode
Burning mouth sensation
Tip of the tongue: Three points
Lateral border of the tongue: Four points
Dorsal surface of the tongue: 10 points
Buccal mucosa: Eight points
Labial mucosa: Five points
Hard palate: Eight points
Soft palate: Three points
Gingiva: Three points by sextant
3. Discussion
In recent years, much knowledge has been gained on the PBM therapy mechanism of action after
a plethora of laboratory, animal, and human studies [
23
25
]. In fact, over 100 phase III randomized
controlled trials and over 1000 laboratory studies have studied the eects of photobiomodulation in
dierent branches of medicine [
24
,
25
]. The biological modulation due to light therapy is the conversion
of luminous energy to metabolic energy, which will lead to the modulation of cell functioning, and it
happens when the near-infrared and infrared light reaches the targeted tissue. Photoacceptors,
also called chromophores, are molecules found in nearly all living cells that absorb light energy and
cause a change in cell function [
26
]. Chromophores typically absorb very specific wavelengths of light
and reflect others, and it is the absorption of energy by chromophores during light irradiation that
determines the specific biological responses [
26
]. Furthermore, it is now established that PBM acts
principally on the chromophore cytochrome c oxidase (CcO) and the intracellular water. The CcO that
is found in the mitochondria is the terminal enzyme of the electron transport chain, intermediating
the electron transfer from cytochrome c to molecular oxygen. Therefore, CcO is implicated in the
ATP production, which means that a stimulation of the CcO will lead to a stimulation in the ATP
production. It was found that CcO acts as a photo-acceptor and transducer of photo-signals in the
red and near-infrared regions of the light spectrum [
27
]. An increase in intracellular ATP is one of the
most frequent and significant findings after PBM both
in vitro
and
in vivo
. Therefore, the stimulated
synthesis of ATP is caused by an increased activity of CcO when activated by PBM. In addition,
photobiomodulation induces a redox eect by stimulating a short and transient activation of the
reactive oxygen species (ROS). Large doses of light, and even more particularly blue light, leads
to the production of ROS, and it is well known that mitochondria are one of the most important
sources of ROS; therefore, the PBM is somehow implicated in the induction of redox eects. Moreover,
PBM is implicated in the activation of transcription factors and signaling pathways, since many of the
secondary mediators of PBM, like the reactive oxygen species, are able to activate transcription factors
and signaling pathways [11].
Acute and chronic oral complication as a side eect of cancer therapy represents a serious
clinical challenge and aects largely the quality of the life of the cancer patients. The fact that
photobiomodulation has shown to be ecient in the curative and preventive management of oral
mucositis has led to a motivation for further studies to apply photobiomodulation therapy in the other,
less frequent, oral complications of cancer therapy [
28
]. Furthermore, studies are being conducted on
the ecacy of PBM in the reduction of neuropathy symptoms and on the possible neuro-regenerative
eects. A prospective, randomized, placebo-controlled study with seven breast cancer patients with
a chemotherapy-induced peripheral neuropathy assessed the ecacy of PBM. Based on the study,
there seems to be a tendency towards the prevention of chemotherapy-induced peripheral neuropathy
with the photobiomodulation therapy [
29
]. In addition, a randomized, sham-controlled clinical trial on
Int. J. Environ. Res. Public Health 2019,16, 4505 8 of 11
70 patients showed that the chemotherapy-induced peripheral neuropathy was significantly reduced,
there was no significant reduction in the sham group, and that the addition of physiotherapy had no
positive income [30].
In this case series, the oral complications managed were oral mucositis, dysphagia, oral dryness,
taste alteration, and burning mouth sensation. To the extent of our knowledge, there are only few
published studies on PBM for the management of dysphagia, oral dryness, burning mouth sensation,
and taste alteration in cancer patients. A review article published by an international multidisciplinary
panel of clinicians and researchers with expertise in the area of supportive care in cancer and PBM
clinical application and dosimetry proposed a new treatment protocol to be used specifically for each
of the oral complications [
19
,
31
]. Therefore, in order to optimize the parameters in this case series,
and with the aim of having a better outcome, the suggested parameters and the treatment protocol by
the international multidisciplinary panel were followed. In this case series, a significant improvement
of taste perception and a significant decrease in the burning mouth sensation was noticed after 10
sessions of the treatment. In addition, a significant reduction of swallowing impairment after five
sessions was noted, and an increase in the whole resting and stimulated saliva quantity was noted after
five sessions. These results indicate that PBM therapy within the suggested parameters and treatment
protocol can be considered as a promising approach for the management of the oral complications due
to cancer therapy.
Despite the frequency of these oral complications in cancer patients, the pathophysiology of these
complications is not fully understood. Dysphagia can be due to anatomical, mechanical, or neurological
changes aecting any structure from the lips to the gastric cardia [
32
]. Dysgeusia during cancer therapy
is usually attributed to the destruction of the dividing taste bud cells and olfactory receptor cells that
are mostly found on the tongue, which explains the recommendations to use the PBM therapy on the
tongue [
33
]. The oral dryness and hyposalivation are usually associated with the irradiation of the
salivary glands and the loss of their function [
34
]. In some cases, apoptosis in parotid glands can be
seen if the doses are relatively high [35]. This process is p53-dependent [34].
Oral mucositis (OM) is the most frequent complication of cancer therapy, having a frequency
of appearance in 80% of patients under high-dose chemotherapy and 80% of patients undergoing
head and neck radiotherapy. A large number of studies have suggested the eectiveness of PBM in
the management of OM [
19
]. In this matter, the levels of evidence for the recommendations by the
MASCC/ISOO on the use of PBM in patients receiving hematopoietic stem cell transplantation (HSCT)
in addition to head and neck cancer (HNC) patients are respectively set at II and III [
36
]. In fact, the
panel of experts recommended the application of PBM as a preventive measure of OM in patients
undergoing high-dose CT with or without total body irradiation before HSCT using the following
parameters: Wavelength at 650 nm, power of 40 mW, and each cm
2
treated with the required time to
a tissue energy dose of 2 J/cm
2
[
19
]. As for the HNC patients, with the lower level of evidence, the
panel “suggests” the use of PBM (wavelength =632 nm) as an OM prevention in patients undergoing
radiation therapy (RT) without concurrent CT [
36
]. Concerning the burning mouth sensation, a recent
meta-analysis that included 10 studies concluded that PBM therapy seems to be eective in the
management of burning mouth sensation [
37
]. However, it is worth noting that the study did not
include any cancer patients. To the best of our knowledge, this case series is the only study available
in literature discussing the use of photobiomodulation for the management of the burning mouth
sensation in a cancer patient. Furthermore, the problem of taste alteration as a consequence of head and
neck radiotherapy and/or high dose chemotherapy has been recently highlighted as it was suggested
to uniform the terminology of such complication to dysgeusia and taste alteration instead of using the
following terms: Ageusia and taste dysfunction [
38
]. For this reason, in this case series, only the terms
“dysgeusia” and “taste alteration” were used [38].
Another important issue is the standardization of the PBM treatment protocol and the laser
irradiation parameters [
39
]. The use of infrared or near-infrared laser light is not only what it takes
to have positive results for the management of oral complications. Several factors, parameters,
Int. J. Environ. Res. Public Health 2019,16, 4505 9 of 11
and conditions influence the therapeutic eects of PBM, including fluence, irradiance, treatment timing
and repetition pulsing, and wavelength. The wavelength, power density, energy density, and time of
exposure must be properly adjusted in order to have a successful treatment [
31
,
39
]. Again, this is why
in this case series the parameters that we used were those suggested in previous published review
articles by experts in the field of PBM and supportive care [19,31].
Lastly, it is important to indicate that the North American Association for photobiomodulation
therapy (NAALT) do not recommend the PBM therapy over an active tumor site to avoid any possible
eect PBM therapy might have on active cancer sites, notably from the belief that there is a risk of
transformation of premalignant cells or stimulation of active cancer cells [
40
]. Moreover, a systematic
review suggests, based on 27 articles that meet the criteria, that the use of PBM in the prevention
and management of cancer treatment toxicities does not lead to the development of tumor safety
issues [
41
]. In accordance with the previous findings, a retrospective study of the safety of PBM in
patients with head and neck cancer showed no eect of PBM upon overall survival, time to local
recurrences, and disease-free survival of patients with head and neck cancer treated with radiotherapy
with/without chemotherapy [42].
This case series suggest the eectiveness of PBM therapy in the management of oral mucositis,
dysphagia, oral dryness, taste alteration, and burning mouth sensation due to cancer therapy. However,
the absence of a control group and the relatively small number of included patients can be considered
as a limitation of the findings. Hence, randomized clinical trials with a control group and a larger
number of included patients using the same treatment protocol and parameters is recommended.
4. Conclusions
Within the limitations of the study, photobiomodulation therapy with the specific parameters
and treatment protocol used in this study can be considered eective in the management of oral
mucositis, dysphagia, oral dryness, taste alteration, and burning mouth sensation due to cancer therapy.
Further studies need to be done to confirm its eectiveness and to identify the optimal parameters and
treatment protocol.
Author Contributions:
M.E.M.; S.N. performed the clinical examination, diagnosis, follow-up, and treatments.
M.E.M.; F.F.; W.E.M.; S.N. wrote the manuscript. M.E.M. and W.E.M. performed the literature review and data
analysis. At the end, all the authors revised the manuscript.
Conflicts of Interest: The authors declare no conflicts of interest.
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©
2019 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access
article distributed under the terms and conditions of the Creative Commons Attribution
(CC BY) license (http://creativecommons.org/licenses/by/4.0/).
... A significant number of studies have proven the beneficial effect of PBM on reducing the adverse effect of cytostatics on the oral mucosa by reducing the inflammation process, reducing pain, preventing fibrosis, and enhancing wound healing and tissue regeneration [2,[15][16][17][18][19][20]. In 2021, our group published a laboratory study on the impact of PBM on human gingival fibroblasts [21]; the in vitro results confirmed the fact that the appropriately selected wavelength and properly selected parameters of the laser settings can increase cell proliferation, modulate inflammatory markers, and decrease the susceptibility of human gingival fibroblasts to apoptosis through the downregulation of apoptosis-related genes. ...
... Having selected the protocol in the laboratory, we wanted to confirm its efficacy in vivo. Mobadder et al. [19], in case series reports of advanced OM, also used this (the suggested PBM) protocol with good treatment effect-fast and uncomplicated healing of oral lesions. Emission type low-frequency pulsed light (<100 Hz) has shown a slight advantage over CW light in the prevention of injury and wound healing rate [4], but unfortunately, the laser we used was not able to provide (set) pulse mode but only CW or gated mode. ...
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The demand for aesthetic procedures is significantly increasing worldwide. In this case report, an in-office laser-assisted protocol coupled with rejuvenating concentrate serum (Gluage, TEBISKIN Gluage, SkinMed, Italy) was made. A 24-year-old female patient presented with a chief complaint of abundant facial acne and localized pigmentation. Clinical examination revealed the presence of abundant acne on the forehead and cheeks and the presence of localized pigmentation. Laser-assisted protocol coupled with rejuvenating concentrate serum was suggested. The protocol consisted of a thorough cleansing of the face followed by irradiation with a 980 nm diode laser (Smart M, Lasotronix, Poland), followed by a 405 nm diode laser (Smart M, Lasotronix, Poland), the application of rejuvenating concentrate serum (Gluage, TEBISKIN Gluage, SkinMed, Italy), and irradiation with the 635 nm diode laser (Smart M, Lasotronix, Poland). The protocol was made once per week for three weeks (three sessions in total), and a three-month follow-up was made after the end of the last session to confirm the effectiveness of the treatment. Stomatology 1 diode laser (Smart M, Lasotronix, Poland) was used in this case report as a 980 nm, 405 nm, and 635 nm diode laser (Smart M, Lasotronix, Poland). During the follow-up period, an almost total reduction of the acne was observed with the total disappearance of the localized pigmentation. This case report confirms the effectiveness of the proposed laser-assisted facial aesthetic treatment. We invite further studies to be made within the same suggested promising protocol.
... Interestingly, the results of an in vitro study conducted by Oron et al., 2007 [100] showed a significant restoration of taste pathway-related ATP production by PBM-treated human neuronal cells in peripheral nerve dysfunction has also been found. This coincides with the histological results of a clinical study conducted by Suarez et al., 2006 [101] and a case reported by El Mobadder et al., 2019 [102]. In this context, it was proposed that a decrease in the tongue gustatory sensitivities on an electrogustometric test on the dorsal surface of the tongue is related to the degeneration of the chorda tympani nerve that leads to trigeminal neuropathy or glossopharyngeal nerve inhibition [103,104]; whereby irradiating the affected areas as well as the trigger points would capture and restore all the symptoms associated with idiopathic NP, ensuring optimal outcomes. ...
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Abstract: Neuropathic pain (NP) can be challenging to treat effectively as analgesic pharmacotherapy (MED) can reduce pain, but the majority of patients do not experience complete pain relief. Our pilot approach is to assess the feasibility and efficacy of an evidence-based photobiomodulation (PBM) intervention protocol. This would be as an alternative to paralleled standard analgesic MED for modulating NP intensity-related physical function and quality of life (QoL) prospectively in a mixed neurological primary burning mouth syndrome and oral iatrogenic neuropathy study population (n = 28). The study group assignments and outcome evaluation strategy/location depended on the individual patient preferences and convenience rather than on randomisation. Our prospective parallel study aimed to evaluate the possible pre/post-benefit of PBM and to allow for a first qualitative comparison with MED, various patient-reported outcome measures (PROMs) based on Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT-II) were used for up to a nine-month follow-up period in both intervention groups (PBM and MED). The PBM protocol applied to the PBM group was as follows: λ810 nm, 200 mW, 0.088 cm2, 30 s/point, 9 trigger and affected points, twice a week for five consecutive weeks, whereas the MED protocol followed the National Institute of Clinical Excellence (NICE) guidelines. Our results showed that despite the severe and persistent nature of the symptoms of 57.50 ± 47.93 months at baseline in the PBM group, a notably rapid reduction in PISmax on VAS from 7.6 at baseline (T0) to 3.9 at one-month post-treatment (T3) could be achieved. On the other hand, mean PISmax was only reduced from 8.2 at baseline to 6.8 at T3 in the MED group. Our positive PBM findings furthermore support more patients’ benefits in improving QoL and functional activities, which were considerably impaired by NP such as: eating, drinking and tasting, whereas the analgesic medication regimens did not. No adverse events were observed in both groups. To the best knowledge of the authors, our study is the first to investigate PBM efficacy as a monotherapy compared to the gold standard analgesic pharmacotherapy. Our positive data proves statistically significant improvements in patient self- reported NP, functionality, psychological profile and QoL at mid- and end-treatment, as well as throughout the follow-up time points (one, three, six and nine months) and sustained up to nine months in the PBM group, compared to the MED group. Our study, for the first time, proves the efficacy and safety of PBM as a potent analgesic in oral NP and as a valid alternative to the gold standard pharmacotherapy approach. Furthermore, we observed long-term pain relief and functional benefits that indicate that PBM modulates NP pathology in a pro-regenerative manner, presumably via antioxidant mechanisms.
... Interestingly, the results of an in vitro study conducted by Oron et al., 2007 [100] showed a significant restoration of taste pathway-related ATP production by PBM-treated human neuronal cells in peripheral nerve dysfunction has also been found. This coincides with the histological results of a clinical study conducted by Suarez et al., 2006 [101] and a case reported by El Mobadder et al., 2019 [102]. In this context, it was proposed that a decrease in the tongue gustatory sensitivities on an electrogustometric test on the dorsal surface of the tongue is related to the degeneration of the chorda tympani nerve that leads to trigeminal neuropathy or glossopharyngeal nerve inhibition [103,104]; whereby irradiating the affected areas as well as the trigger points would capture and restore all the symptoms associated with idiopathic NP, ensuring optimal outcomes. ...
Article
Full-text available
Neuropathic pain (NP) can be challenging to treat effectively as analgesic pharmacotherapy (MED) can reduce pain, but the majority of patients do not experience complete pain relief. Our pilot approach is to assess the feasibility and efficacy of an evidence-based photobiomodulation (PBM) intervention protocol. This would be as an alternative to paralleled standard analgesic MED for modulating NP intensity-related physical function and quality of life (QoL) prospectively in a mixed neurological primary burning mouth syndrome and oral iatrogenic neuropathy study population (n = 28). The study group assignments and outcome evaluation strategy/location depended on the individual patient preferences and convenience rather than on randomisation. Our prospective parallel study aimed to evaluate the possible pre/post-benefit of PBM and to allow for a first qualitative comparison with MED, various patient-reported outcome measures (PROMs) based on Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT-II) were used for up to a nine-month follow-up period in both intervention groups (PBM and MED). The PBM protocol applied to the PBM group was as follows: λ810 nm, 200 mW, 0.088 cm2, 30 s/point, 9 trigger and affected points, twice a week for five consecutive weeks, whereas the MED protocol followed the National Institute of Clinical Excellence (NICE) guidelines. Our results showed that despite the severe and persistent nature of the symptoms of 57.50 ± 47.93 months at baseline in the PBM group, a notably rapid reduction in PISmax on VAS from 7.6 at baseline (T0) to 3.9 at one-month post-treatment (T3) could be achieved. On the other hand, mean PISmax was only reduced from 8.2 at baseline to 6.8 at T3 in the MED group. Our positive PBM findings furthermore support more patients’ benefits in improving QoL and functional activities, which were considerably impaired by NP such as: eating, drinking and tasting, whereas the analgesic medication regimens did not. No adverse events were observed in both groups. To the best knowledge of the authors, our study is the first to investigate PBM efficacy as a monotherapy compared to the gold standard analgesic pharmacotherapy. Our positive data proves statistically significant improvements in patient self-reported NP, functionality, psychological profile and QoL at mid- and end-treatment, as well as throughout the follow-up time points (one, three, six and nine months) and sustained up to nine months in the PBM group, compared to the MED group. Our study, for the first time, proves the efficacy and safety of PBM as a potent analgesic in oral NP and as a valid alternative to the gold standard pharmacotherapy approach. Furthermore, we observed long-term pain relief and functional benefits that indicate that PBM modulates NP pathology in a pro-regenerative manner, presumably via antioxidant mechanisms.
Chapter
Among the different sensory systems, gustation is one of the most elaborate. In its sensory task, gustation is helped by interactions with other sensory systems (olfaction, vision, auditory and somatosensory, trigeminal and thermal sensations). It allows the detection and identification of soluble compounds which can be ingested or must be avoided. This function is fundamental to ingestive behavior (energy intake and selection of nutrients) in order to meet physiological needs. Taste is also fundamental to the genesis of hedonic sensations and therefore the desire to eat (appetite). The tasting step is also the first stage of the digestion, absorption, and storage of nutrients due to anticipatory reflexes. Taste disorders are therefore not simple hedonic alterations of the Epicurean canon of gastronomy; taste disorders can worsen and even compromise vital functions (malnutrition and aggravation of an underlying disease) and they always reduce quality of life. Many drugs and numerous diseases can cause gustatory loss. The mechanisms leading to taste alteration are varied. In medical practice, taste problems are frequent but not diagnosed often enough, in particular in metabolic syndrome and obesity, in neurodegenerative diseases, and in cancer. Increasing knowledge of taste disorders in disease could improve our understanding of taste pathophysiology and the prevention of malnutrition by diets adapted to taste impairment.
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Background The standard therapeutic approach for locally advanced head and neck cancer is optimal use of radiation therapy with or without concomitant chemotherapy. The most common and distressing acute complication of such therapies is oral/pharyngeal mucositis that may be associated with severe morbidity and can interfere with the planned administration of therapy. Methods We have identified all patients diagnosed with head/neck cancer between 2005 and 2009, having received radiotherapy with or without cisplatin-based chemotherapy. Radiotherapy consisted of intensity-modulated radiation therapy (IMRT) in all patients. In patients with grade > 2 mucositis, photobiomodulation (PBM) consisted of three sessions of low-level laser irradiation weekly, in accordance with recently published recommendations for PBM. Patients who did not receive PBM were those for whom that approach was not requested by the radiotherapists and those who declined it. Results Two hundred twenty-two patients (62%) received PBM and 139 did not (39%). The patient’s characteristics were equally distributed between the two groups. For overall survival, time to local recurrence, and progression-free survival, there was no statistical evidence for a difference in prognosis between patients with and without PBM. In a multivariate analysis, after adjusting for known prognostic factors, we found no statistical evidence that PBM was related to overall survival, progression-free survival, or local recurrence. Conclusions Our results show evidence of no effect of PBM upon overall survival, time to local recurrences, and disease-free survival of patients with head and neck cancer treated with radiotherapy with/without chemotherapy.
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The discomfort of patients due to dentinal hypersensitivity (DH) is one of the main challenges that dentists face in daily practice. Difficulties in DH treatment gave rise to many protocols which are currently used. The aim of this clinical study is to evaluate the effectiveness of a new protocol on the reduction of dentinal hypersensitivity with diode laser 980 nm and the application of a graphite paste. 184 patients enrolled in the study, the degree of pain was evaluated by visual analog scale (VAS), graphite paste was applied on the exposed dentine before irradiation, the application of diode laser 980 nm with continuous mode, backward motion, tangential incidence of the beam in non-contact mode and a delivery output of 1 W. Fiber’s diameter was 320 μm and total exposure time depended on the time necessary to remove the graphite paste from the teeth. Statistical analyses were performed with Prism 5® software. Pain in post-operative significantly decreased immediately after the treatment. Mean values stayed stable until a 6-month follow-up. The application is considered to be safe with long-term effectiveness.
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Here, we examined the combined effect of pulse wave photobiomodulation (PBM) with curcumin-loaded superparamagnetic iron oxide (Fe3O4) nanoparticles (curcumin), in an experimental mouse model of acute skin wound. Thirty male adult mice were randomly allocated into 5 groups. Group 1 was served as the control group. Group 2 was a placebo and received distilled water, as a carrier of curcumin. Group 3 received laser (890 nm, 80 Hz, 0.2 J/cm²). Group 4 received curcumin by taking four injections around the wound. Group 5 received laser + curcumin. One full-thickness excisional round wound was made on the back of all the mice. On days 0, 4, 7, and 14, bacterial flora, wound surface area, and tensile strength were examined and microbiological examinations were performed. In case of wound closure, the two-way ANOVA shows that wound surface area of entire groups decreased progressively. However, the decrease in laser + curcumin and laser groups, and especially data from laser + curcumin group were statistically more significant, in comparison with the other groups (F statistics = 2.28, sig = 0.019). In terms of microbiology, the two-way ANOVA showed that laser, and laser + curcumin groups have statistically a lower bacterial count than the curcumin, control, and carrier groups (F statistics = 35, sig = 0 = 000). Finally, the one-way ANOVA showed that laser + curcumin, curcumin, and curcumin significantly increased wound strength, compared to the control and carrier groups. Furthermore, laser + curcumin significantly increased wound strength, compared to the control, laser, and curcumin groups (LSD test, p = 0.003, p = 0.002, and p = 0.005, respectively). In conclusion, curcumin nanoparticles, pulse wave laser, and pulse wave laser + curcumin nanoparticles accelerate wound healing, through a significant increase in wound closure rate, as well as wound strength, and a significant decrease in Staphylococcus aureus counts. Furthermore, the statistical analysis of our data suggests that the combined treatment of pulse wave laser + curcumin nanoparticles enhances the wound closure rate, and wound strength, compared to the laser and curcumin nanoparticles alone.
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Objective: Perform systematic literature review on photobiomodulation (PBM) devices used at home for nonesthetic applications. Background: Home-use PBM devices have been marketed for cosmetic and therapeutic purposes. This is the first systematic literature review for nonesthetic applications. Methods: A systematic literature search was conducted for PBM devices self-applied at home at least thrice a week. Two independent reviewers screened the articles and extracted the data. Treatment dosage appropriateness was compared to the World Association for Laser Therapy (WALT) recommendations. The efficacy was evaluated according to the relevant primary end-point for the specific indication. Results: Eleven studies were suitable. Devices were applied for a range of indications, including pain, cognitive dysfunction, wound healing, diabetic macular edema, and postprocedural side effects, and were mostly based on near-infrared, pulsed light-emitting diodes with dosages within WALT recommendations. Regarding efficacy, studies reported mostly positive results. Conclusions: Home-use PBM devices appear to mediate effective, safe treatments in a variety of conditions that require frequent applications. Conclusive evaluation of their efficacy requires additional, randomized controlled studies.
Thesis
Chemotherapy-induced peripheral neuropathy (CIPN) is a common side effect of chemotherapeutic agents used to treat breast cancer (BC). This complication involves paresthesia, numbness and burning pain in the distal limbs. Photobiomodulation therapy (PBMT) is based on the application of (near)-infrared light on tissue to stimulate cell repair processes. Previous research has demonstrated that it can promote functional recovery of peripheral nerves. We hypothesize that PBMT is an effective treatment strategy to prevent sensory symptoms associated with CIPN leading to an improved patient's quality of life. A prospective, randomized, placebo-controlled study with 7 BC patients was performed at the Jessa Hospital, Belgium. Patients were randomized to receive PBM or placebo treatments twice-weekly starting at first until the last week of their chemotherapy. The modified Total Neuropathy Score (mTNS) and Functional Assessment of Cancer Therapy/ Gynaecologic Oncology Group Taxane scale (FACT/GOG-Taxane) was used to evaluate the severity of CIPN and the patients' quality of life respectively. Currently we cannot state that PBMT prevents the emergence of CIPN. This can be explained by the small sample size. Nonetheless, based on patients' experience, there seem to be a tendency in the prevention of CIPN with PBMT. In order verify this, a follow-up study is needed to increase the sample size.
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Background: Photobiomodulation (PBM) therapy is a rapidly growing approach to stimulate healing, reduce pain, increase athletic performance, and improve general wellness. Objective: Applying PBM therapy over the site of a tumor has been considered to be a contraindication. However, since another growing use of PBM therapy is to mitigate the side effects of cancer therapy, this short review seeks to critically examine the evidence of whether PBM therapy is beneficial or harmful in cancer patients. Materials and methods: PubMed and Google Scholar were searched. Results: Although there are a few articles suggesting that PBM therapy can be detrimental in animal models of tumors, there are also many articles that suggest the opposite and that light can directly damage the tumor, can potentiate other cancer therapies, and can stimulate the host immune system. Moreover, there are two clinical trials showing increased survival in cancer patients who received PBM therapy. Conclusions: PBM therapy may have benefits in cancer patients and should be further investigated.
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