Photobiomodulation therapy assisted orthodontic tooth movement:potential implications,challenges,and new perspectives

Over the past decade,dramatic progress has been made in dental research areas involving laser therapy.The photobiomodulatory effect of laser light regulates the behavior of periodontal tissues and promotes damaged tissues to heal faster.Additionally,photobiomodulation therapy(PBMT),a non-invasive treatment,when applied in orthodontics,contributes to alleviating pain and reducing inflammation induced by orthodontic forces,along with improving tissue healing processes.Moreover,PBMT is attracting more attention as a possible approach to prevent the incidence of orthodontically induced inflammatory root resorption(OIIRR)during orthodontic treatment(OT)due to its capacity to modulate inflammatory,apoptotic,and anti-antioxidant responses.However,a systematic review revealed that PBMT has only a moderate grade of evidence-based effectiveness during orthodontic tooth movement(OTM)in relation to OIIRR,casting doubt on its beneficial effects.In PBMT-assisted orthodontics,delivering sufficient energy to the tooth root to achieve optimal stimulation is challenging due to the exponential attenuation of light penetration in periodontal tissues.The penetration of light to the root surface is another crucial unknown factor.Both the penetration depth and distribution of light in periodontal tissues are unknown.Thus,advanced approaches specific to orthodontic application of PBMT need to be established to overcome these limitations.This review explores possibilities for improving the application and effectiveness of PBMT during OTM.The aim was to investigate the current evidence related to the underlying mechanisms of action of PBMT on various periodontal tissues and cells,with a special focus on immunomodulatory effects during OTM.

A phaseⅡprospective trial of photobiomodulation therapy in limiting oral mucositis in the treatment of locally advanced head and neck cancer patients

Objective:This study aimed to compare the historical incidence rate of severe oral mucositis(OM)in head and neck cancer patients undergoing definitive concurrent chemoradiation therapy(CRT)versus a prospective cohort of patients with locally advanced head and neck squamous cell carcinoma(HNSCC)treated with prophylactic photobiomodulation therapy(PBMT).Methods:This US-based,institutional,single-arm,phaseⅡprospective clinical trial was initiated in 50 patients(age≥18 years,Karnofsky Performance Scale Index>60,with locally advanced HNSCC(excluding oral cavity)receiving definitive or adjuvant radiation therapy(RT)with concurrent platinum-based chemotherapy(CT).PBMT was delivered three times per week throughout RT utilizing both an intraoral as well extraoral delivery system.Primary outcome measure was incidence of severe OM utilizing both the National Cancer Institute Common Toxicity Criteria,version 4.0(NCI-CTCAE)Grade≥3 and the World Health Organization Mucositis Grading Scale(WHO)Grade≥3 versus historical controls;secondary outcome measures included time to onset of severe OM following therapy initiation.Results:At baseline,all patients included in final analysis(N=47)had OM Grade 0.Average RT and CT dose was(66.3±5.1)Gy and(486.1±106.8)mg/m ^(2),respectively.Severe OM was observed in 11 of 47 patients(23%,confidence interval:12,38).OM toxicity grade trended upward during treatment,reaching a maximum at 7 weeks(WHO:1.8 vs.NCI-CTCAE:1.7).Subsequently,OM grade returned to baseline 3 months following completion of RT.The mean time to onset of severe OM was(35±12)days.The mean time to resolution of severe OM was(37±37)days.Conclusions:Compared to historical outcomes,PBMT aides in decreasing severe OM in patients with locally advanced HNSCC.PBMT represents a minimally invasive,prophylactic intervention to decrease OM as a major treatment-related side effect.