Lasers in surgical periodontics and oral medicine

Effects of Semiconductor Laser Irradiation on Differentiation of Human Dental Pulp Stem Cells in Co-Culture with Dentin

This study aimed to determine the effect of photobiomodulation therapy induced by semiconductor laser irradiation on human dental pulp stem cell (hDPSC) proliferation and their differentiation into odontoblast-like cells (OLCs). The effects of various semiconductor laser irradiation conditions on hDPSCs were examined. Three groups were evaluated: a single laser irradiation at 6 h post-seeding, multiple laser irradiations up to four times every 4 days after the first dose, and a control with no laser irradiation. The cells were irradiated at 10, 30, and 150 mW using a semiconductor laser. The effect of laser irradiation on hDPSC differentiation into OLCs was also determined. Four groups were evaluated, including co-culture using basic medium and dentin discs, simple culture using OLC differentiation-inducing medium, co-culture using OLC differentiation-inducing medium and dentin discs, and control culture with basic medium. The expression of the nestin, ALP, DSPP, and DMP-1 genes was measured using real-time PCR. The multiple irradiation group irradiated at 30 mW exhibited significantly more cell proliferation than the control. The expression of nestin associated with differentiation into OLCs during each culture period tended to be lower, whereas DSPP and ALP expression was higher compared with that of the control. Multiple laser irradiations at a low power of 30 mW induced significant hDPSC proliferation and might induce differentiation into OLCs.

The Effects of Antimicrobial Photodynamic Therapy Used to Sterilize Carious Dentin on Rat Dental Pulp Tissue

Antimicrobial photodynamic therapy (aPDT) used to sterilize carious dentin may irritate pulp tissues because of tissue-penetrating laser and singlet oxygen generation. This study aimed to assess the effects of aPDT on rat pulp tissues. A cavity formed in a rat maxillary first molar was treated with aPDT. The combined photosensitizer and laser irradiation conditions in the aPDT groups were as follows: methylene blue and 100 mW for 60 s, brilliant blue (BB) and 100 mW for 60 s, BB and 50 mW for 120 s, and BB and 200 mW for 30 s. Each cavity was treated with an all-in-one adhesive and filled with flowable resin. aPDT was not applied for the control. In each group, the rats were sacrificed on postoperative days 1 and 14, and thin sections of the treated teeth were prepared. Pulp tissue disorganization (PTD), inflammatory cell infiltration (ICI), and tertiary dentin formation (TDF) were evaluated. At 1-day evaluation, there were significant differences between the aPDT group and controls with respect to PTD and ICI (p < 0.01); 14 days later, almost all specimens showed tertiary dentin formation. The application of aPDT caused reversible damage to the rat pulp, while in the long term, healing occurred with the formation of tertiary dentin.

Laser-Assisted Depigmentation-An Introspection of the Science, Techniques, and Perceptions

Background: Gingival hyperpigmentation is a major concern for a significant number of patients, as a relevant aesthetic or cosmetic need. Oral melanin pigmentation is considered to be multifactorial and could be related to physiological or even pathological reasons and can be the consequence of a variety of local or systemic factors. This pigmentation varies individually across races or age groups and is without any gender predilection. Evidence gleaned from literature is presented from case–control studies and from the authors’ own research work in prospective, split-mouth, double-blinded, clinical trials comparing treatment modalities in effecting depigmentation. Methods: A systematic review of published articles, using suitable assay criteria, was carried out to formulate a consensus on laser-assisted modalities. A total of 295 published sources were subject to critical analysis and resulted in six papers that were subject to data scrutiny. Additionally, evidence is presented on clinical protocols and treatment outcomes. Results: Analysis of randomized clinical studies identified the use of two laser wavelength groups—near infrared diode and erbium group of mid-infrared lasers. Several areas of analysis were examined, and inconsistent degrees of significance were obtained to establish which laser group was optimal and if they were any better than scalpel depigmentation. Conclusion: A definitive conclusion is wanting as studies with scientific and standardized protocols of evaluation are yet to provide a take on comparative assessments between different techniques of depigmentation.

The First Application of Nanoelectrochemotherapy in Feline Oral Malignant Melanoma Treatment-Case Study

Simple Summary

The current study concerns feline melanoma of the oral cavity, which is rather rarely diagnosed but is usually correlated with poor prognosis. Here we proposed a new treatment modality using CO₂ laser surgery with pulsed electric fields with ultra-short pulses in combination with bleomycin. The applied nanoelectrochemotherapy resulted in positive response and satisfactory animal recovery. Thus, nanosecond electroporation seems a reasonable anticancer approach in domestic animals.

Abstract

Background: The aim of this study was to present the first domestic animal trial of nanosecond electroporation with chemotherapy and CO₂ laser surgery. Methods: sixteen-year-old domestic cat with diagnosed melanoma on oral cavity was the case used in the study. Firstly, CO₂ laser surgery was used for the removal of most of tumor mass. Then nanoelectrochemotherapy with bleomycin was applied including appropriate margin of healthy tissue. A 15 ± 4 kV/cm × 15 ns pulsing protocol was employed with a total of 800 ± 100 pulses. Only one session of nanoelectrochemotherapy (nanoECT) was performed. Results and conclusions: during the next two weeks areas of focal necrosis were replaced by the granulation tissue. Complete wound healing was observed four weeks after initial treatment. After 15 weeks post treatment, no local recurrence was apparent.

Efficacy and safety of diode laser during circumvestibular incision for Le Fort I osteotomy in orthognathic surgery: a triple-blind randomized clinical trial

The aim of this triple-blind randomized clinical trial was to evaluate the efficacy and safety of diode laser during circumvestibular incisions for Le Fort I osteotomy in orthognathic surgeries in comparison with conventional techniques using electrocautery and scalpel. Patients were randomly allocated to one of three groups based on the technique employed to perform incisions: diode laser, electrocautery, and scalpel. The parameters used to evaluate the efficacy and safety of diode laser were incision velocity, duration of surgery, bleeding rate, alterations in postoperative functions, pain, edema, wound clinical healing, and infection. Thirty patients were enrolled in the study (10 per group). Regarding bleeding, the incisions performed with diode laser promoted a lower bleeding rate compared with scalpel and electrocautery (p = 0.00). The diode surgical laser was effective during the incision procedure, but required a longer time to perform the incisions compared with the other techniques evaluated (p < 0.05). No statistically significant difference was detected between groups regarding total surgical time or other safety parameters (p > 0.05). Thus, diode laser proved to be effective and safer during circumvestibular incisions for Le Fort I osteotomy than conventional devices.

Diode Laser - A Novel Therapeutic Approach in the Treatment of Chronic Periodontitis in Type 2 Diabetes Mellitus Patients: A Prospective Randomized Controlled Clinical Trial

Introduction: Maturity-onset diabetes mellitus affecting the elderly population is marked by insulin resistance and decreased insulin production. The relationship between periodontitis and diabetes is bidirectional. Type 2 diabetic patients are more prone to chronic periodontitis (CP) and severe periodontitis affects the glycemic control in such patients. Recently, dental diode laser has become an effective tool in controlling CP. To date, very few studies have been conducted to check the efficacy of diode laser in control of periodontal destruction in type 2 diabetes mellitus (DM2) patients. Hence, the need of the study was to evaluate whether diode laser helps improvement of periodontal outcome and reduction in anaerobic bacteria in elderly diabetic patients with CP. Methods: Forty DM2 patients with CP were randomized into group A (control): scaling and root planing (SRP) only and group B (test): SRP followed by soft tissue dental diode laser (808 nm) application. Four patients (2 in each group) were lost during follow up. Clinical parameters, plaque samples and glycated hemoglobin levels were evaluated at both baseline and 90 days post-treatment. Results: Improvement in clinical, microbiological and glycemic parameters were noted in the group that received SRP as well as SRP + LANAP (laser-assisted new attachment procedure). The reductions in clinical parameters were statistically significant after 3 months (P<0.001). The microbial analysis of plaque samples for Aggregatibacter actinomycetemcomitans (Aa) and Porphyromonas gingivalis (Pg) decreased significantly after 3 months in group B than in group A. Glycated hemoglobin level (HbA1c) decreased significantly after 90 days in both the groups (P<0.001) with more reduction in the SRP+LANAP group (6.49%) in comparison to SRP alone (16.25% vs. 9.76%). However, on the intergroup comparison, the difference in HbA1c reduction was nonsignificant. Conclusion: Laser as an adjunct to SRP is an effective procedure for improving clinical and microbiological parameters in maturity onset diabetes mellitus patients with CP. Also, there was a better improvement in glycemic control in the test group compared to control group after 3 months. Hence, medically compromised patients like DM2 with CP with delayed wound healing can effectively be treated by laser as an adjunct to nonsurgical periodontal therapy for better results.

Comparative evaluation of efficacy and soft tissue wound healing using diode laser (810 nm) versus conventional scalpel technique for second-stage implant surgery

Background:

This study was aimed to compare the efficacy and soft tissue wound healing using diode lasers (810 nm) versus conventional scalpel approach as uncovering technique during the second-stage surgery in implants. This was a prospective, randomized study which was conducted on 20 subjects in which the implants were already placed using a two-stage technique. Implant sites were examined and the patients were randomly divided into two groups.

Materials and Methods:

Patients were randomly divided into two groups, i.e., Group A and Group B. In Group A, implants were uncovered as a part of Stage II surgery with conventional scalpel technique, and in Group B, implants were uncovered using 810 nm diode laser. Clinical parameters such as need and amount of local anesthesia, duration of surgery, intraoperative bleeding, pain index, wound healing index (HI), and time for impression taking were recorded at various intervals.

Results:

Statistical differences for clinical parameters were seen between Group A and Group B showing uncovery of implant with laser more effective, and for time of impression taking, difference was statistically significant showing that impressions were taken early in case of Group A because of better healing which was recorded with help of HI, but the difference in time of healing between Group A and Group B was not statistically significant.

Conclusion:

The use of a diode laser (810 nm) in the second-stage implant surgery can minimize surgical trauma, reduce the amount of anesthesia, improve visibility during surgery due to the absence of bleeding, and eliminate postoperative discomfort.

High-power diode laser in the circumvestibular incision for Le Fort I osteotomy in orthognathic surgery: a prospective case series study

The incisions during orthognathic surgery are classically performed with conventional scalpel or electrocautery. Considering that the high-power diode laser surgery may provide advantages when compared to conventional incision techniques, the current study aimed to present a prospective case series of patients submitted to circumvestibular incision for Le Fort I osteotomy. Ten patients with dentofacial deformities who underwent to rapid assisted maxillary expansion or bimaxillary orthognathic surgery were enrolled in the study. All incisions were performed by a single surgeon using an 808-nm diode laser, with an optical fiber of 600 μm, at a power of 2.5 W, in a continuous-wave mode. The performance of the incision was evaluated by incision velocity, bleeding, edema, secondary infection, clinical healing, and pain. The velocity of the incision ranged from 0.10 to 0.20 mm/s (mean 0.13 ± 0.03 mm/s). Considering bleeding during the soft tissue incision, all surgeries were classified as absent bleeding. All patients presented a clinical healing of the surgical wound in a period that range from 3 to 5 weeks and experienced swelling during the follow-up period. On average, approximately 50% of the swelling had resolved after the third postoperative week, and 28.8% of swelling remained after 2 months after the surgery. The pain decreased after 2 and 3 days, and 90.0% of the patients reported no pain after 7 postoperative days. High-power diode laser is effective and safety during circumvestibular incisions for Le Fort I osteotomy in orthognathic surgery decreasing bleeding, surgery time, pain, and edema after orthognathic surgery.

A preliminary randomized clinical trial comparing diode laser and scalpel periosteal incision during implant surgery: impact on postoperative morbidity and implant survival

The aim of this preliminary randomized clinical trial was to compare: (1) post-operative morbidity after application of laser or scalpel incision for flap advancement during implant surgery and bone grafting and (2) implant survival rate following flap advancement with laser or scalpel incision after 6 months of loading. Eighteen patients who were scheduled for dental implant placement and simultaneous bone grafting were randomly assigned to test or control groups. Diode laser (810 nm, 2 W, pulse interval 200 μs; pulse length 100 μs, 400-μm initiated fiber tip), or scalpel (control) was used to sever the periosteum to create a tension-free flap. Visual analogue scale (VAS) pain score, rate of nonsteroid anti-inflammatory drug (NSAID) consumption, intensity of swelling, and ecchymosis were measured for the six postsurgical days. Six months after loading, implant survival was assessed. VAS pain score (during the first four postoperative days), rate of NSAID consumption (during the first three postoperative days), and intensity of swelling (during the first five postoperative days) were significantly lower in the test group compared to the control group (All P values < 0.05). One patient in the control group experienced ecchymosis. All implants were successful in function. Application of laser for performing periosteal releasing incision reduced the incidence and severity of postoperative morbidity of the patients undergone implant surgery in conjunction with bone augmentation procedure. We did not find any detrimental effect of laser incision on the implant survival within 6 months of loading.

Diode Laser Assisted Excision and Low Level Laser Therapy in the Management of Mucus Extravasation Cysts: A Case Series

Introduction: Mucus extravasation cyst is a commonly occurring lesion in oral cavity that may result from traumatic severance of a salivary gland duct with subsequent extravasation of mucus into fibrous connective tissue. After a conventional excision or marsupialization, recurrence is not uncommon. Diode laser offers an effective modality for management of such lesions. Case Reports: Four patients were referred with painless fluctuant swellings on labial and buccal mucosa. After recording history and clinical examination, provisional diagnosis of mucocele was made. All the lesions were excised with a diode laser and biopsy was performed. Surgical wounds were treated with low-level laser therapy (LLLT). Results: Uneventful healing was observed in all 4 cases. Significant reduction in postoperative discomfort was recorded after application of LLLT. Histopathological findings were suggestive of mucus extravasation cysts. Conclusion: Diode laser appears to be a good alternative to conventional modalities for the management of mucus extravasation cysts.

Periosteal Releasing Incision With Diode Laser in Guided Bone Regeneration Procedure: A Case Series

Introduction: Periosteal releasing incision (PRI) is nearly always essential to advance the flap sufficiently for a tension-free flap closure in bone augmentation procedures. However, hematoma, swelling, and pain are recognized as the main consequences of PRI with scalpel. The aim of this case series was to investigate the effectiveness of laser-assisted PRI in guided bone regeneration (GBR) procedure. In addition, postoperative hematoma, swelling, and pain and implant success were assessed. Methods: Seventeen patients needed GBR were included in this study. Diode laser (940 nm, 2 W, pulse interval: 1 ms, pulse length: 1 ms, contact mode, 400-μm fiber tip) was used in a contact mode to cut the periosteum to create a tension-free flap. Facial hematoma, swelling, pain, and the number of consumed nonsteroidal anti-inflammatory drugs (NSAIDs) were measured for the six postoperative days. Six months after implant loading, implant success was evaluated. Results: Minimal bleeding was encountered during the procedure. A tension-free primary closure of the flap was achieved in all cases. The clinical healing of the surgical area was uneventful. None of the patients experienced hematoma, ecchymosis, or intense swelling after surgery. The mean value of maximum pain (visual analogue scale - VAS) was 20.59 ± 12.10 mm (mild pain). Patients did not need to use NSAID after four postoperative days. All implants were successful and functional and none of them failed after 6 months of implant loading. Conclusion: This study revealed the effectiveness of laser-assisted PRI in GBR procedure. This technique was accompanied with minimal sequelae at the first postoperative week. All implants were successful and no complication was noted during the course of this study.

Evaluation of Patient Perceptions After Vestibuloplasty Procedure: A Comparison of Diode Laser and Scalpel Techniques

INTRODUCTION

Inadequate vestibular depth results in poor plaque control owing to an insufficient width of keratinized gingiva. Vestibuloplasty provides the necessary vestibular depth and can be performed either with a scalpel, electrocautery or lasers.

AIM

To evaluate the patient perceptions related to pain and discomfort on the 1(st), 3(rd) and the 7(th) day post vestibuloplasty and also assess the healing outcomes related to the treatment of inadequate vestibular depth either with the diode laser or the scalpel.

MATERIALS AND METHODS

Twenty patients who had inadequate vestibular depth and required vestibuloplasty were assigned randomly to undergo the procedure either with the scalpel or the laser. The data obtained was analysed for intergroup comparison with an independent paired t-test and intragroup comparison was determined by a paired t-test.

RESULTS

Intragroup comparison within the laser group for VAS scores of pain and discomfort within all the reported days exhibited a significant difference (p<0.05). Inter group comparison revealed that the patients in the laser group had lower VAS cores for pain and discomfort compared to the scalpel group (p<0.05). Analysis of the three pointer scale for healing revealed that the patients in the laser group exhibited better healing outcomes on the 1(st), 3(rd) and the 7(th) day compared to the scalpel group.

CONCLUSION

Observations from the study highlight the opinion that laser can be a safe and effective alternative to traditional vestibuloplasty performed with the scalpel.

Management of a Recurrent Pyogenic Granuloma of the Hard Palate with Diode Laser: A Case Report

INTRODUCTION

Pyogenic granuloma (PG) is a prevalent inflammatory hyperplasia of skin and oral mucosa which is often caused by constant low-grade local irritation, traumatic injury or hormonal factors. In many cases, gingival irritation and inflammation due to poor oral hygiene are precipitating factors. Oral PG occurs predominantly on the gingiva, but it is also encountered on the lips, tongue, buccal mucosa and rarely on the hard palate. Although surgical excision is the first choice of treatment, many other treatment modalities could be counted such as cryosurgery, sodium tetradecyl sulfate sclerotherapy, intralesional steroids, flash lamp pulsed dye laser, neodymium-doped yttrium aluminium garnet (Nd:YAG) laser, carbon dioxide (CO2) laser, erbium-doped yttrium aluminum garnet (Er:YAG) lasers and diode laser have been suggested. After surgical excision recurrence occurs up to 16% of these lesions. It is believed that recurrence ensues as a result of incomplete excision, failure to eliminate etiologic factors or repeated trauma.

CASE REPORT

A 50-year-old female was referred to the Department of Oral Surgery, Gazi University, School of Dentistry, complaining of a swelling and growth on the right side of the hard palate for four months. Patient reported a similar growth in the same area about two years earlier, which had turned out to be a PG by histopathology. The treatment plan included surgical excision of the lesion using diode laser.

RESULTS

The patient reported no pain after the surgery. She was discharged with a prescription of chlorhexidine mouthwash and necessary post-operative instructions. At 7 days follow up visit, immediate recurrence of the lesion was observed, and it was excised by diode laser with 2 mm margins at its clinical periphery, to a depth up to the periosteum, by the same operator. No recurrence or scarring was observed in 14 months follow-up.

CONCLUSION

Although diode laser is a secure and efficient technique for the treatment of intraoral PG, in order to minimize its recurrence, the lesion should be excised with a wider margin down to the periosteum or to the causing agent. Also due to its high recurrence rate, long-term follow-up is recommended.

Laser assisted periodontics: A review of the literature

Over the years, the use of the laser within health field and more particularly dentistry has been increasing and improving. The application of laser in the periodontal treatment takes part of a non-surgical and surgical approaches, is used for the decontamination of periodontal pockets due to its bactericidal effect, and the removal of granulation tissues, inflamed and diseased epithelium lining, bacterial deposits and subgingival calculus. However in spite of all the marketing surrounding, the use of laser highlighting its beneficial effect, the capacity of laser to replace the conventional treatment for chronic periodontitis is still debatable. In fact there is no evidence that any laser system adds substantial clinical value above conventional treatments of chronic periodontitis. Some studies showed a significant positive effect on clinical attachment level gain and probing depth reduction. In the other hand, several articles demonstrated no evidence of the superior effectiveness of laser therapy compared to root planing and scaling. Our aims is to review the literature on the capacity of erbium:Yttrium-aluminum-garnet and neodymium:Yttrium-aluminium-garnet laser to either replace or complete conventional mechanical/surgical periodontal treatments.

Laser and radiosurgery in veterinary dentistry

Lasers and radiosurgery frequently used in human dentistry are rapidly entering veterinary dental use. The carbon dioxide, diode, and low-level therapy lasers have features including hemostasis control, access to difficult to reach areas, and decreased pain, that make them useful for oral surgery. Periodontal pocket surgery, gingivectomy, gingivoplasty, gingival hyperplasia, operculectomy, tongue surgery, oropharyngeal inflammation therapy, oral mass surgery, crown, and frenectomy laser surgeries are described, including images.

Lasers in periodontics

Laser is one of the most captivating technologies in dental practice since Theodore Maiman in 1960 invented the ruby laser. Lasers in dentistry have revolutionized several areas of treatment in the last three and a half decades of the 20^th century. Introduced as an alternative to mechanical cutting device, laser has now become an instrument of choice in many dental applications. Evidence suggests its use in initial periodontal therapy, surgery, and more recently, its utility in salvaging implant opens up a wide range of applications. More research with better designs are a necessity before lasers can become a part of dental armamentarium. This paper gives an insight to laser in periodontics.