Effect of laser irradiation on the growth and development of fetal mouse limbs in an in vitro model

Investigation of active matrix- metaloproteinase-8 (aMMP-8) as a reference parameter for path control in antimicrobial photothermal therapy (aPTT) using a split-mouth design

OBJECTIVES

This retrospective data-collection study aims to explain how the active matrix-metalloproteinase-8-titer (aMMP-titer) influences the immune response of the subject. This is done through monotherapy scaling and root planing (SRP) which is then compared to SRP combined with antimicrobial photothermal therapy (aPTT, Emundo®).

METHODS

Data collection was monocentric, randomized and split-mouth based. A study group of twenty patients with chronic periodontal disease with a periodontal pocket depth (PPD) 4 mm ≤ PPD ≤8 mm, a periodontal screening index (PSI: > 3), and a gingival recession ≤2 mm were selected.A diode laser, manufactured by A.R.C. Laser GmbH, with 810 nm wavelength was used. This device implemented three different light transmission systems for transgingival and intra-gingival irradiation. Power settings between 200 and 300 mW were deployed for 10 s during all treatment steps. The photothermic dye of EmunDo® system (A.R.C. Laser GmbH) was infracyaningreen.The adjuvant effect of the antimicrobial photothermal therapy (aPTT) with EmunDo® in combination with conventional SRP on the teeth 15 and 35 was compared with the results of monotherapy SRP on teeth 25 and 45.

RESULTS

A reduction of the aMMP-8-titer in gingival crevicular fluid (GCF) was observed in both groups (follow up group and control group) after one month. However; the decrease in the follow up group under SRP in combination with aPTT was significantly more pronounced. The periodontal pocket depths was reduced in both treatment groups. The periodontal probing depth (in mm) shows a larger decrease of the periodontal pocket depth within the follow up group (SPR with aPTT) compared with the control group (SRP).

CONCLUSION

The aMMP-8-titer showed differences in both groups prior to and after treatment. Active matrix-metalloproteinase-8 (aMMP-8) as a reference parameter for path control in antimicrobial photothermal therapy (aPTT) seems acceptable.

Comparison of Early Oncological Results of Diode Laser Surgery with Radiotherapy for Early Glottic Carcinoma

Objective

To evaluate the oncologic results of transoral endolaryngeal microscopic diode laser surgery (MDLS) and radiotherapy (RT) for T1 and T2 glottic carcinoma.

Study Design

Case series with planned chart review.

Setting

Ankara Oncology Education and Research Hospital.

Subjects and Methods

The study was conducted on a series of 140 cases of early glottic carcinoma (T1, T2) treated with MDLS or RT. The tumors were defined according to T stage and the involvement of the anterior commissure (AC).

Results

The 3-year locoregional control rate of MDLS and RT groups was 93.1% and 89.7%, respectively ( P = .434). There was no difference in 3-year disease-free survival when comparing T1 and T2 tumors treated with MDLS and those treated with RT ( P = .618 for T1, P = .084 for T2). There was no difference in disease-free survival when comparing AC– and AC+ tumors treated with MDLS and those treated with RT ( P = .291 for AC– and P = .530 for AC+ tumors).

Conclusions

Microscopic diode laser surgery in early glottic cancer seems to be an oncologically safe procedure that has similar oncological results with RT. In T2 glottic tumors and AC involvement, the results with either treatment are less satisfactory.

The efficacy of low-power lasers in tissue repair and pain control: a meta-analysis study

OBJECTIVE

We used statistical meta-analysis to determine the overall treatment effects of laser phototherapy on tissue repair and pain relief.

BACKGROUND DATA

Low-power laser devices were first used as a form of therapy more than 30 years ago. However, their efficacy in reducing pain or promoting tissue repair remains questionable.

METHODS

Following a literature search, studies meeting our inclusion criteria were identified and coded. Then, the effect size of laser treatment, that is, Cohen's d, was calculated from each study using standard meta-analysis procedures.

RESULTS

Thirty-four peer-reviewed papers on tissue repair met our inclusion criteria and were used to calculate 46 treatment effect sizes. Nine peer-reviewed papers on pain control met the inclusion criteria and were used to calculate nine effect sizes. Meta-analysis revealed a positive effect of laser phototherapy on tissue repair (d = +1.81; n = 46) and pain control (d = +1.11; n = 9). The positive effect of treatment on specific indices of tissue repair was evident in the treatment effect sizes determined as follows: collagen formation (d = +2.78), rate of healing (d = +1.57), tensile strength (d = +2.13), time needed for wound closure (d = +0.76), tensile stress (d = +2.65), number and rate of degranulation of mast cells (d = +1.87), and flap survival (d = +1.95). Further, analysis revealed the positive effects of various wavelengths of laser light on tissue repair, with 632.8 nm having the highest treatment effect (d = +2.44) and 780 nm the least (d = 0.60). The overall treatment effect for pain control was positive as well (d = +1.11). The fail-safe number-that is, the number of studies in which laser phototherapy has negative or no effect-needed to nullify the overall outcome of this analysis was 370 for tissue repair and 41 for pain control.

CONCLUSIONS

These findings mandate the conclusion that laser phototherapy is a highly effective therapeutic armamentarium for tissue repair and pain relief.

Effects of ultrasound delivered through a mist of saline to wounds in mice with diabetes mellitus

OBJECTIVE

To examine the effects of ultrasound administered through a fine mist of saline on surgically placed full-thickness excisional wounds in mice with experimental diabetes mellitus.

METHOD

Fifty male CD-I mice received alloxan monohydrate (100 mg/kg), a drug known to induce diabetes mellitus. The animals received five ultrasound (n = 27) or sham (n = 23) treatments for 1.5 minutes, on alternate days, for 10 days, and were then sacrificed. Following sacrifice, each animal's wound was excised and the tissues prepared for qualitative and quantitative histological analysis.

RESULTS

No difference in wound-surface area was found between the groups after the treatment period. However, blinded assessment of tissue sections revealed significantly increased deposition of collagen and blood vessels in the granulation tissue of animals treated with ultrasound compared with those that received sham therapy.

CONCLUSION

Ultrasound delivered through a fine mist of saline significantly altered the composition of newly formed granulation tissue in animals with experimental diabetes mellitus. Further research needs to be completed to determine other effects of this novel ultrasound therapy and to examine its clinical effectiveness.