Lack of clinical evidence on low-level laser therapy (LLLT) on dental titanium implant: a systematic review

The effect of photobiomodulation therapy on implant stability: A systematic review and meta-analysis

This study was designed to determine the effect of photobiomodulation therapy on dental implant stability. A complete systematic search was performed in PUBMED/MEDLINE, COCHRANE library databases, EMBASE, SCOPUS, and Google Scholar databases on articles published until June 2024. All the RCTs and CCTs reported the solo impact of photobiomodulation on dental implant stability in humans were included. The means and standard deviation for implant stability and sample size were extracted for the meta-analysis. The statistical analysis was conducted using Stata 17 software, and random effect models were applied to assess the source of heterogeneity. The I2 statistic was used to estimate the significance of any discrepancies in the therapy result. After a full-text inspection, 17 articles were qualified for systematic review, and 14 were included in the meta-analysis. Statically significant differences in implant stability were observed between the laser and the control groups on weeks 2 in ISQ reporting groups (p = 0.01, CI 95%) and weeks 4 and 8 in PTV reporting groups (p < 0.001, CI 95%). Despite limitations, the study suggests that PBM therapy benefits patients with dental implants at different periods, particularly during the early phases of healing.

Parameter-Tuned Pulsed Wave Photobiomodulation Enhances Stem Cells From Apical Papilla Differentiation: Evidence From Gene and Protein Analyses

This study examines the effects of pulsed wave photobiomodulation (pwPBM) on the osteogenic differentiation of stem cells from the apical papilla (SCAP). Using 810 nm near-infrared (NIR) light with 300 Hz pulses and a 30% duty cycle, pwPBM was applied at a total energy density of 750 mJ/cm2. Osteogenesis was evaluated through both in vitro and in vivo analyses. In vitro experiments demonstrated significant enhancement of alkaline phosphatase (ALP) activity, along with upregulation of key osteogenesis-related genes and proteins, as confirmed by real-time polymerase chain reaction (PCR) and Western blot analyses. In vivo, histological assessments following SCAP transplantation revealed increased bone tissue formation, further corroborated by osteocalcin staining. These findings underscore the potential of pwPBM as an innovative and effective tool for dental tissue regeneration and engineering.

The Effects of Surface Patterning and Photobiomodulation on the Osseointegration of Titanium Implants in Osteoporotic Long Bones: An In Vivo Study in Rats

This study aimed to assess the impact of titanium surface patterning used in combination with photobiomodulation therapy on enhancing osseointegration in osteoporotic bone fractures. C.p. titanium implants were employed, half with an unmodified surface and half with a modified one, showing a nanostructured cellular surface. Surface patterning aimed to obtain a complex morphology designed for better osseointegration, using a selective anodization process after photoresist coating. A total of 52 rats were used, of which 4 were sacrificed 12 weeks after ovariectomy to evaluate bone density. A total of 48 rats received titanium implants in both tibiae and underwent surgery for implant placement and bone fracture. Half of the rats were subjected to photobiomodulation. The times of sacrifice were 2, 4, and 6 weeks after finalizing LASER therapy. The evaluation methods were micro-CT scanning, the mechanical pull-force test, and morphology. Mechanical tests revealed a significant difference in the surface-patterned titanium with the LASER group at 2 weeks, but not at 4 and 6 weeks. This group outperformed regular titanium and titanium/LASER groups. Micro-CT showed no significant differences, while the morphology indicated better bone quality at 4 weeks in all LASER-treated groups. The effect of surface patterning and photobiomodulation leads to better osseointegration, especially in the earlier stages.

Effect of 980 nm photobiomodulation delivered by a handpiece with Gaussian vs. Flat-Top profiles on proliferation and differentiation of buccal fat pad stem cells

The aim of this study was to compare the effectiveness of the Gaussian and Flat-Top profiles in proliferation and differentiation of mesenchymal stem cell of buccal fat pad. Based on the timing schedule and type of laser handpieces, the cells were assigned to a control group with no radiation, and two irradiation test groups (980 nm) with Flat-Top (F) (power of 1.1 W, beam area of 1 cm2) and standard Gaussian (G) (power of 0.7 W, beam area of 0.5 cm2) handpieces. Each test group was divided into three subgroups, receiving one time (60 J/cm2), two times (120 J/cm2), and three times (180 J/cm2) irradiation. 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) and Annexin V tests were performed. The Alizarin Red staining and polymerase chain reaction tests were done both at the beginning and the end of the first and second weeks. The degree of mineralization and expression of osteogenic markers, RUNX2, OCN, and OPN were evaluated. Based on the MTT and Annexin V test results, both test groups outperformed the control group in degrees of cell proliferation during the first day of laser irradiation (p < 0.05). After one and two times irradiation, the expression of osteogenic markers in the test groups was significantly higher than the control group. PBM with Flat-Top and Gaussian handpieces can enhance ossification and cell differentiation regardless of the type of handpieces.

Effect of postoperative 660-nm low-level laser therapy on the radiographic crestal bone loss of fresh-socket dental implants

Background

Although the benefits of low-level laser therapy (LLLT) in soft tissue healing have been demonstrated, the effects of laser on bone have remained controversial. This study investigated the impact of postoperative 660-nm LLLT on the radiographic crestal bone loss of fresh-socket dental implants.

Methods

Thirty patients referred to the Department of Oral and Maxillofacial Surgery for tooth extraction and placement of fresh-socket implants were selected and assigned to two groups: laser (intervention) and no-laser (control) groups. Immediately after tooth extraction, the implant was inserted into the tooth socket. 660-nm LLLT was immediately started after surgery and was repeated three times per week for two weeks. Bone quantification at the implant site was assessed using periapical intraoral radiographs and computerized software immediately after surgery and after six months.

Results

This study showed a statistically significant difference in mean bone resorption between the mesial and distal aspects of the two groups, with lower bone resorption in the laser group compared to the no-laser group.

Conclusion

The results of this study suggest that LLLT can effectively reduce bone resorption in fresh-socket implant placement. This might indicate the positive effect of LLLT on bone resorption reduction.

Effectiveness of concentrated growth factor and laser therapy on wound healing, inferior alveolar nerve injury and periodontal bone defects post-mandibular impacted wisdom tooth extraction: A randomized clinical trial

The extraction of wisdom teeth with mandibular impact frequently results in complications including damage to the inferior alveolar nerve (IAN) and malformations of the bone. The objective of this research endeavour was to assess the efficacy of low-level laser therapy and concentrated growth factor (CGF) in facilitating nerve recovery and wound healing in such instances. A total of thirty-one patients (mean age 27.52 ± 5.79 years) who presented with IAN injury after extraction were randomly assigned to one of three groups: control group (which received oral mecobalamin), CGF group (which received CGF gel applied to the extraction sockets) and laser group (which received low-level lasers (808 nm, 30 mW, 10 J/cm2 )) at the extraction site. Patients' recovery from IAN paresthesia was evaluated seven times over the course of 14 days utilizing visual analogue scale (VAS) and the pinprick test (PP). At multiple intervals following surgery, periodontal probing and bone level measurements were utilized to assess the recovery of both soft and hard tissues. The findings revealed that, compared with the control group, both the CGF and laser treatment groups exhibited a markedly greater improvement in VAS scores and wound healing of soft tissues, as well as in PP results (p < 0.001), indicating enhanced wound healing processes. Despite these improvements, there was no significant difference in wound healing outcomes between the CGF and laser groups. Notably, the CGF group showed a statistically significant improvement in healing bone defects at 30 and 90 days post-treatment compared with the control group (p = 0.003 and p = 0.004, respectively), underscoring its effectiveness in bone healing as a critical aspect of the overall wound healing process. However, in terms of other wound healing comparisons, no significant differences were observed. CGF and laser therapy significantly enhanced the healing of wounds, including soft tissue and bone recovery, in addition to accelerating the recovery of IAN injuries following mandibular wisdom tooth extraction. Although both treatments were equally effective in nerve recovery, CGF notably excelled in promoting bone healing, suggesting its pivotal role in comprehensive wound healing. This highlights that both CGF and laser therapy are viable options for not only nerve recovery but also for overall wound healing in such dental procedures.

Use of Photobiomodulation to Reduce Postoperative Pain, Edema, and Trismus After Third Molar Surgery: A Systematic Review and Meta-Analysis

PURPOSE

Third molar extraction can cause surgical trauma, which is associated with pain, edema, trismus, and functional limitations. The aim of the present systematic review was to investigate the effects of photobiomodulation (PBM) following the extraction of impacted mandibular third molars.

METHODS

An electronic search was conducted in 10 databases from inception up to October 2021 and the grey literature, with no restrictions regarding language or year of publication. Randomized controlled clinical trials (RCT) were included. Studies that were not RCTs were excluded. Reviewers independently analyzed titles and abstracts, followed by full-text analysis. This systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The exposure variable was the use of PBM and the outcomes were pain, edema, and trismus. Meta-analysis was performed using a random-effects model. The estimate was calculated considering standardized mean differences (SMD) and respective 95% confidence intervals (CI) obtained for each outcome on the first, second, third and seventh postoperative days. The level of evidence was assessed using the GRADE approach.

RESULTS

The search resulted in the 3,324 records. Thirty-three RCTs were included in the systematic review and 23 of these were included in the meta-analyses. The studies involved a total of 1,347 participants (56.6% female and 43.4% male) between 16 and 44 years of age. A greater reduction in pain was found in the PBM group compared to the control group on the third postoperative day (SMD: -1.09; 95% CI: -1.63; -0.55; P < .001; low certainty). Edema was discretely lower in the PBM group on the second postoperative day (SMD: -0.61; 95% CI: -1.09; -0.13; P < .001; low certainty) and trismus was discretely lower in the PBM group on the seventh postoperative day (SMD: 0.48; 95% CI: 0.00; 0.96; P < .001; very low certainty).

CONCLUSION

The evidence of the effect of PBM regarding the control of pain, edema, and trismus following third molar extractions is low or very low.

The Role of Low-Level Laser Therapy in Bone Healing: Systematic Review

Low-level laser therapy (LLLT) is a treatment that is increasingly used in orthopedics practices. In vivo and in vitro studies have shown that low-level laser therapy (LLLT) promotes angiogenesis, fracture healing and osteogenic differentiation of stem cells. However, the underlying mechanisms during bone formation remain largely unknown. Factors such as wavelength, energy density, irradiation and frequency of LLLT can influence the cellular mechanisms. Moreover, the effects of LLLT are different according to cell types treated. This review aims to summarize the current knowledge of the molecular pathways activated by LLLT and its effects on the bone healing process. A better understanding of the cellular mechanisms activated by LLLT can improve its clinical application.

Effect of LED photobiomodulation on dental implant osseointegration: An in vivo study

Background

Photobiomodulation (PBM) may be prescribed after dental surgery to accelerate tissue healing and improve implant stability. The objective of this study is to evaluate the efficiency of LED-PBM on the dental implant osseointegration.

Methods

A total of 48 implants (KontactTM) were inserted in 8 Yucatan minipigs (6 implants per minipig) divided into 2 groups (test and control). The test group received LED-PBM with a total energy of 124.2 J/cm2 delivered over 4 sessions (at day0, day+8, day+15 and day+28) lasting 12 minutes each. At day+28, all animals were sacrificed, and their mandibles removed to perform histologic and histomorphometric analysis. Implant osseointegration was evaluated using the computation of bone/implant contact (BIC) index and bone surface/total surface (BS/ TS) ratio. The groups were compared using Student's unpaired t test.

Results

BIC index and BS/TS ratio were significantly higher within the test group as compared to the control group (P<0.01). Histologic observations on bone tissues demonstrated that LED-PBM may improve and accelerate dental implant osseointegration: 25% of dental implants analyzed within the test group were completely osseointegrated, versus 12.5% within the control group.

Conclusion

This experimental study indicates that LED-PBM contributes to enhancing implant treatment outcomes.

The Influence of Low-Level Laser Therapy on CBCT Radiographic and Biochemical Profiles of Type II Controlled Diabetic Patients After Dental Implant Insertion: A Randomized Case-Control Study

Background Low-level laser treatment (LLLT) was thought to increase bone quality during osseointegration when combined with dental implants. However, there is no sufficient information on its impact on dental implants in diabetics. Osteoprotegerin (OPG) has been described as a marker for bone turnover to determine implant prognosis. The current research aims to evaluate the effect of low-level laser therapy (LLLT) on bone density (BD) and osteoprotegerin levels in peri-implant crevicular fluid (PICF) in type II diabetic patients. Methods This study comprised 40 individuals with type II diabetes mellitus (T2DM). Implants were randomly placed in 20 non-lasered T2DM patients (control) and 20 lasered T2DM patients (LLLT group). At the follow-up stages, BD and OPG levels in the PICF were evaluated in both groups. Results Significant variations were shown among control and LLLT groups concerning OPG level and BD (p≤0.001). OPG was significantly decreasing with follow-up points (p≤0.001). There was a significant decrease in OPG with time in both groups with a higher decrease in the control group. Conclusion LLLT is promising in controlled T2DM patients due to its outstanding influence on BD and estimated crevicular levels of OPG. Regarding its clinical significance, LLLT significantly improved bone quality during osseointegration on dental implants in T2DM. LLLT is considered potentially important for T2DM patients during implant placement. Trial registration The study was registered on ClinicalTrial.gov under registration number NCT05279911 (registration date: March 15, 2022) (https://clinicaltrials.gov/ct2/show/NCT05279911).

Effect of Low-Level Laser Therapy on Bone Formation in Rapid Palatal Expansion: A Systematic Review

Introduction: Crossbite is a common malocclusion with a 7-23% prevalence rate. Treatment is based on the expansion of the mid-palatal suture (MPS) with Rapid Palatal Expansion(RPE) followed by a retention period to reach new bone maturation, enough to maintain the results stable. This systematic review was conducted to evaluate the effectiveness of low-level laser therapy (LLLT) in increasing bone formation in MPS. Methods: This article was written by the PRISMA checklist. Electronically, 3 databases, namely PubMed, Scopus, and Embase, were searched with the keywords selected based on PICO. Time (2010-2021) and language restrictions were performed. Results: 528 articles, out of which 374 studies were screened, were found, and 9 full-text articles were subsequently included considering these inclusion criteria: randomized clinical trial (RCT) that examines the efficacy of LLLT in rapid palatal expansion (RPE), age under 15 years, non-surgical RPE with a tooth-supported appliance, and low-intensity laser application. Finally, 4 articles were appraised by Cochrane version 5.2.0 with 7 domains. 3 of 4 articles showed LLLT has a significant impact on bone formation. One of them showed no significant difference in pain perception and bone density between the laser and non-laser groups. Conclusion: While many studies have assessed the effect of LLLT on bone formation in animal models, high-quality clinical trials are missing in this regard. The available clinical trials suggest a positive effect of LLLT on sutural bone formation after RPE.

The Effects of Photobiomodulation on Bone Defect Repairing in a Diabetic Rat Model

The purpose of this study is to examine the prospective therapeutic effects of photobiomodulation on the healing of bone defects in diabetic mellitus (DM) using rat models to provide basic knowledge of photobiomodulation therapy (PBMT) during bone defect repair. For in vitro study, an Alizzarin red stain assay was used to evaluate the effect of PBMT on osteogenic differentiation. For in vivo study, micro-computed tomography (microCT) scan, H&E and IHC stain analysis were used to investigate the effect of PBMT on the healing of the experimental calvarial defect (3 mm in diameter) of a diabetic rat model. For in vitro study, the high glucose groups showed lower osteogenic differentiation in both irradiated and non-irradiated with PBMT when compared to the control groups. With the PBMT, all groups (control, osmotic control and high glucose) showed higher osteogenic differentiation when compared to the non-irradiated groups. For in vivo study, the hyperglycemic group showed significantly lower bone regeneration when compared to the control group. With the PBMT, the volume of bone regeneration was increasing and back to the similar level of the control group. The treatment of PBMT in 660 nm could improve the bone defect healing on a diabetic rat calvarial defect model.

Assessment of the Healing of Dental Implant Surgical Site Following Low-Level Laser Therapy Using Bioclinical Parameters: An Exploratory Study

The purpose of this study was to evaluate whether low-level laser therapy improves healing of the implant surgical site with clinical and biochemical parameters. Thirty patients with an edentulous space spanning a single tooth were selected. The patients were randomly allocated to 1 of 2 groups: control group and test group. The test group received laser energy at a power of 2 J/cm2 with a total of 4-6 J energy over each implant. Clinical parameters (implant stability quotient, probing index, modified sulcus bleeding index) and osteoprotegerin were assessed at baseline and follow-up intervals (2 weeks, 6 weeks, and 3 months). The test group showed significantly higher implant stability quotient than the control group at 2 weeks (57.93 ± 3.95 vs 35.67 ± 3.08; P < . 01) and 3 months (58.86 ± 3.75 vs 67.06 ± 3.78; P < . 01). A significant rise in osteoprotegerin levels of the test group (686.30 ± 125.36 pg/mL at baseline and 784.25 ± 108.30 pg/mL at 3 months; P < . 01) was seen contrary to significant decline in the control group (839.50 ± 249.08 pg/mL at baseline vs 415.30 ± 78.39 pg/mL at 3 months; P < . 01). Within the limitations of the study, the findings suggest that the healing of peri-implant hard and soft tissues may be enhanced with the use of low-level laser therapy as an explicit modality during the postoperative period.

Influence of low-level laser therapy on implant stability in implants placed in healed sites: a randomized controlled trial

Background

The present study aims to assess the influence of low-level laser therapy (LLLT) on stability in implants placed in healed sites.

Material and methods

The present study followed the SPIRIT statement and is reported according to CONSORT. Patients were randomly allocated to LLLT or control groups. LLLT consisted in the application of 808-nm GaAlA laser applied before the preparation of the implant bed and after suturing (80 seconds; 11J/cm²). Implant stability quotient (ISQ) and the distance between the implant platform to the alveolar bone crest (millimeters) were assessed at implant placement (T₀) and the abutment selection phase (4–6 months, T_a).

Results

A total of 64 implants were placed in 33 patients. The insertion torque ranged from 10 to 70 N.cm (mean 43.23; SD ±16.82). The T₀ ISQ ranged from 18 to 95.5 (mean 61.7; SD ±18.23) and the crestal bone radiographic distance was 2.03 mm (SD±1.27). At T_a, the ISQ ranged from 39 to 90 (mean 64.2; SD±9.84), and the mean crestal bone radiographic loss was 1.70mm (SD±1.65). However, no differences were observed when LLLT and control groups were compared with ISQ difference (T_a–T₀; p=0.598) or radiographical peri-implant alterations (p=0.531).

Conclusion

LLLT did not influence the implant stability in implants placed in healed sites compared to a control group.

Trial registration

ReBEC, RBR-35TNJ7. Registered May 23, 2018

Photobiomodulation in Periodontology and Implant Dentistry: Part 1

(Part 2 of this article can be located at www.liebertpub.com/doi/10.1089/photob.2019.4731.) Objective: Finding evidence-based treatment strategies for low-level light therapy (LLLT) and the correct incorporation of these treatment methods in the clinical practice of periodontics. Background: Photobiomodulation has been shown to have biostimulatory, anti-inflammatory and analgesic effects that can be beneficial in periodontal and dental implant treatment procedures. Methods: In this review we have addressed some clinical questions regarding the potential clinical application of low-level light irradiation and its photobiomodulatory effects in periodontology and implantology. The literature was searched for in vivo (animal or clinical) articles written in English in four electronic databases of PubMed, Scopus, Google Scholar, and Cochrane Library until April 2019. Only studies with low irradiation doses without any thermal effects used only for their photobiomodulatory purposes were included. Results: We were able to find relevant studies for all of our questions, and positive effects for the application of light therapy were reported in most of the studies. However, there is still great deal of heterogeneity in terms of study designs and most importantly in light irradiation devices and the parameters used. Owing to this issue it was not possible to reach specific evidence-based irradiation protocols for the questions addressed in this review. Conclusions: Based on our search results, an obvious positive effect of LLLT on stimulation of healing of periodontal soft and hard tissues and reduction of inflammation can be seen. Future well-designed randomized control studies with the same irradiation settings and systematic reviews evaluating the studies found on the questions mentioned are necessary to reach evidence-based recommendations.

Effect of Low-Level Laser Irradiation on Stability and Marginal Bone of Narrow Implants Retaining Overdentures in Moderately Controlled Diabetic Patients

The researchers investigated the influence of low-level laser irradiation (LLLI) on implant stability and marginal bone of small-diameter implants retaining mandibular overdentures in patients with moderately controlled diabetes. Twenty patients (mean age = 59.32 ± 4.1 years) with moderately controlled diabetes mellitus (glycated hemoglobin A1c [HbA1c] = 8.1%-10.0 %) were rehabilitated by maxillary and mandibular conventional dentures. Two small-diameter implants (3 × 12 mm) were inserted in the canine areas of the mandible and immediately loaded by mandibular dentures. In a split-mouth design, LLLI was applied to 1 of the 2 implants in a random order (study group [SG]); the other implant was left as a control (control group [CG]). For each patient, gallium aluminum-arsenide diode low-level laser (940-nm wavelength, 0.50 ± 2 mW output power, 0.004 cm² spot size; Epic, Biolase, Inc, San Clemente, Calif) was applied around each implant with total delivered energy of 90 J (equally divided by 6 irradiation points) in 3 sessions. The application was done immediately after implant insertion, 3 days and 1 week after surgery. Implant stability (measured by Periotest) and marginal bone loss (MBL; measured by cone beam computerized tomography) were evaluated at implant loading (T1), 6 months (T6), and 12 months (T12). One implant failed in the CG and no failures occurred in the SG, resulting in 95% and 100% survival rates, respectively. The SG recorded higher Periotest values than the CG at all observation times. However, the difference was significant (P = .039) at T6 only. The SG recorded lower MBL values than the CG. No difference in MBL was detected between groups or peri-implant sites (mesial, distal, buccal, and lingual) at T6 and T12. Within the limits of this study, LLLI had no effect on marginal bone around immediately loaded small-diameter implants retaining overdentures in patients with moderately controlled diabetes. However, it was beneficial in improving implant stability 6 months after overdenture insertion.

Effect of photobiomodulation on the stability and displacement of orthodontic mini-implants submitted to immediate and delayed loading: a clinical study

The aim of this study was to evaluate the effect of photobiomodulation (PBM) on the stability and displacement of orthodontic mini-implants (MIs) submitted to loading. Forty-eight and 35 mini-implants (1.5 × 8 × 1 mm) were assessed for stability and displacement, respectively (19 patients). MIs were allocated according to the intervention in 1-PBM + immediate loading (IL), 2-PBM + delayed loading (DL) (four weeks after implantation), 3-IL only, and 4-DL only. PBM (Therapy XT, DCM) was implemented using a red emission (660 nm, 4 J/cm², 0.1 W, 20 s) immediately after implantation (day 0) and infrared emissions (808 nm; 8 J/cm², 0.1 W, 40 s) in the following appointments every 48-72 h during two weeks (days 2, 4, 7, 9, 11, and 14). Loading of 150 gF was applied during three months for all MIs. The stability was assessed by resonance frequency analysis (Osstell ISQ), and images from Cone beam computed tomography were evaluated to determine the amount of the displacement of the MI's head. MIs from the PBM groups presented lower loss of stability (P = 0.0372). When the analysis considered the loading protocol as an additional variable, group two showed the lowest loss of stability, being significantly different from groups that did not receive PBM (P = 0.0161). There was no difference between groups two and four during the period without loading (P > 0.05). DL groups presented lower loss when the effective period of loading was assessed, independently of the application of PBM (P < 0.0001). All groups showed displacement of the MIs head without significant differences (P > 0.05). DL potentiated the effect of PBM, decreasing the loss of stability.

Clinical evidence of photobiomodulation therapy (PBMT) on implant stability and success: a systematic review and meta-analysis

Background

Photobiomodulation therapy (PBMT), a type of light therapy that uses the concept of photobiomodulation, is developed to promote bone healing. Clinical studies have been conducted to assess the influence of PBMT on dental implant stability and success rate. This is the first systematic review and meta-analysis to assess the effect of PBMT and methodological quality of these studies on implants in human clinical trials.

Methods

An electronic search was performed in Pubmed, Embase, and the Cochrane Controlled Register of Trials (CENTRAL).

Results

Initially, 675 articles were identified, among which only 8 met the inclusion criteria. Four of the 8 studies presented a low risk of bias, whereas the other 4 were of moderate risk. Our review focused on implant success rates and implant stability measured at days 0 and 10, and at 3, 4, 6, and 12 weeks. No significant differences were observed between the PBMT group and the control group regarding implant stability or success rate.

Conclusions

The existing clinical studies did not provide sufficient evidence to observe positive effects of PBMT on implants in patients. An increased number of high-quality clinical randomized controlled trials (RCTs) are required to verify the data and to draw convincing conclusions.

Can Low-Level Laser and Light-Emitting Diode Enhance the Stability of Dental Implants?

Purpose

Stability of dental implants is an important factor for evaluation of osseointegration. The aim of this study was to evaluate the effect of combined use of low-level laser (LLL) and light-emitting diode (LED) therapy on the stability of dental implants during the healing phase.

Materials and Methods

This was a randomized clinical trial. Patients were assigned to two groups: In group 1, patients received LLL and LED 20 min/day for 10 days after implant insertion. Patients in group 2 (controls) did not undergo LLL and LED. The implant stability quotient (ISQ) was measured at 0 (time 0), 10 (time 1), 21 (time 2), 42 (time 3) and 63 days (time 4) after implant placement. Independent t test was used to compare the ISQs between the two groups.

Results

Fifty-eight patients were studied in two groups (n = 28). The mean ISQ did not differ immediately after insertion (P > 0.05). The mean ISQ differed significantly between the two groups on days 10, 21, 42 and 63 (P < 0.05). Results demonstrated an increase in the amount of ISQ in group 1 (intervention) at times 1, 2, 3 and 4. In the control group, the amount of ISQ decreased on days 10 and 21 following implant insertion, but increased afterward on days 42 and 63.

Conclusion

The results of this study showed that simultaneous use of LLL and LED increased the stability of the implants after 9 weeks of follow-up.

A pilot study of laser energy transmission through bone and gingiva

BACKGROUND

The use of low-level laser therapy is growing in the field of dentistry especially in orthodontics to speed up tooth movement and in implantology to aid osseointegration. In these dental applications, the laser energy needs to penetrate through the periodontium to the target site to stimulate photobiomodulation. The percentage of energy loss when laser is transmitted through the periodontium has not been previously studied. With the use of an 808-nanometer diode laser, the aim was to investigate the percentage loss of laser energy when transmitted through the periodontium to the extraction socket.

METHODS

The percentage energy loss of an 808-nm diode laser through the periodontium was measured in 27 tooth sockets by using a specifically designed photodiode ammeter.

RESULTS

For each millimeter of increased bone thickness there was 6.81% reduction in laser energy (95% confidence interval, 5.02% to 8.60%). The gingival thickness had no statistically significant effect on energy penetration.

CONCLUSION

Energy penetration depends markedly on bone thickness and is independent of gingival thickness.

PRACTICAL IMPLICATIONS

To the best of the authors' knowledge, this study is one of the first to investigate laser penetration through the periodontium. Evidence from this study showed that laser energy penetration through the periodontium is markedly affected by bone thickness but less so by gingival thickness. Clinicians need to be aware of the biological factors that could affect laser energy penetration to the target site and adjust their laser dosages accordingly. These findings may guide dental practitioners in selecting the appropriate laser dosage parameters for low-level laser therapy.

Laser for bone healing after oral surgery: systematic review

The purpose of this study is to perform a systematic review on the use of lasers in oral surgery for bone healing. Selection of articles was carried out by two evaluators in Pubmed and Web of Science databases for published articles and OpenGray for gray literature. Search strategy was developed based on the PICO Question "Does the use of lasers after oral surgery improve bone healing?". Eligibility criteria were: being on laser; evaluate bone healing; involve oral surgery; do not be about implant, periodontics, orthodontics, osteonecrosis or radiotherapy, nor revisions, clinical cases, etc. Data were collected from each article in a structured spreadsheet and a descriptive analysis was performed. Risk assessment of bias of the articles was carried out through the tool elaborated by the Cochrane collaboration. A total of 827 potentially relevant references were identified. No articles were found in OpenGray. Eleven articles met the eligibility criteria and were included in the systematic review. Most of studies were in vivo and in jaw, being conducted with low-power lasers which were applied immediately after the surgical procedure of extraction. Neoformation and bone density were the outcomes of choice and there was a tendency of increase in bone density, neoformation, regeneration, mineralization, or bone condensation when laser was applied. Regarding the bias risk assessment, studies were not clear in reporting most of the parameters. Low-power laser therapy seems to reduce time of bone healing in oral surgery, although there are no defined protocols and the level of evidence is still considered weak.

Influence of low-level laser therapy on the healing of human bone maxillofacial defects: A systematic review

PURPOSE

This systematic review evaluates the effectiveness of low-level laser therapy (LLLT) to enhance maxillofacial area bone repair.

METHODS

A comprehensive search of studies published up to February 2017 and listed in PubMed/MEDLINE, Scopus, and Cochrane Library databases was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement.

RESULTS

The 15 selected studies evaluated a total of 374 patients (mean age, 28.5years) who were treated with LLLT. Gallium-arsenide (GaAs) and gallium aluminium arsenide (GaAlAs) were the most commonly used devices, and LLLT parameters varied greatly. Wavelengths varied from 500 to 1000nm. Tooth extraction, distraction osteogenesis, maxillary expansion, periodontal defects, orthodontic movement and maxillary cystic defects were evaluated. From the 15 selected studies, six evaluated bone repair (primary outcomes). Of these, four studies showed improvement in bone formation after using LLLT, two demonstrated improved results for only one follow up period, and one showed no additional benefits. The other 9 studies evaluated secondary parameters related to healing (secondary outcomes) in the maxillofacial area after applying LLLT, including anti-inflammatory, analgesic, and healing accelerator effects, and quality of life related to oral health. There were no adverse or negative effects of LLLT reported.

CONCLUSION

Within the limitation of this review, a possible improvement in bone density can be found when LLLT is applied postoperatively in maxillofacial bony defects. LLLT also seems to promote anti-inflammatory and analgesic effects and accelerate healing, as well as enhance quality of life related to oral health. However, LLLT use protocols need to be standardized before more specific conclusions can be drawn about this subject.

Non-thermal atmospheric pressure plasma functionalized dental implant for enhancement of bacterial resistance and osseointegration

OBJECTIVE

Even though roughened titanium (Ti) and Ti alloys have been clinically used as dental implant, they encourage bacterial adhesion, leading to failure of the initial stability. Here, the non-thermal atmospheric pressure plasma jet (NTAPPJ) functionalized Ti and Ti alloy were investigated to promote cellular activities but inhibit the initial attachment of the adherent pioneer bacterium, Streptococcus sanguinis, without topographical changes.

METHODS

After the produced radicals from NTAPPJ were characterized, bacterial adhesion to specimens was assessed by PrestoBlue assay and live-dead staining with or without the NTAPPJ functionalizing. After the surface was characterized using optical profilometry, X-ray photoelectron spectroscopy and contact angle analysis, the ions released from the specimens were investigated. In vitro initial cell attachment (4h or 24h) with adhesion images and alkaline phosphatase activity (ALP, 14 days) measurements were performed using rat bone marrow-derived mesenchymal stem cells.

RESULTS

The initial bacterial adhesion to the Ti and Ti alloy was significantly inhibited after NTAPPJ functionalizing (p<0.05) compared to those without NTAPPJ functionalizing. The bacterial adhesion-resistance effect was induced by carbon cleaning, which was dependent on the working gas used on the Ti specimens (nitrogen>ammonia and air, p<0.05). The initial cell adhesion with well-developed vinculin localization and consequent ALP activity at 14days to the NTAPPJ-functionalized specimens were superior to the non-treated specimens.

SIGNIFICANCE

For the promising success of dental implants, NTAPPJ functionalizing is suggested as a novel surface modification technique; this technique can help ensure the success of integration between the dental implants and bone tissues with less concern of inflammation.