Current concepts in the use of lasers in periodontal and implant dentistry

A clinical protocol for immediate dental implant placement in post-extraction-infected sites decontaminated with Er,Cr:YSGG laser

BACKGROUND

Placement of dental implants into fresh extraction sockets offers some advantages, such as reduced treatment times and enhanced patient comfort. The Er,Cr:YSGG (Erbium, Chromium-doped: Yttrium, Scandium, Gallium, and Garnet) laser can significantly reduce bacterial concentration after the extraction of a compromised tooth. The aim of this article is to provide a clinical protocol for the management of implants placed in infected extraction sites decontaminated with Er,Cr:YSGG laser.

METHODS

A compromised tooth, which was an abutment for a fixed bridge, with clinical and radiological signs of infection was extracted. The infected site was treated and decontaminated with an Er,Cr:YSGG laser device (Biolase iPlus®) and two implants (Straumann®) were placed in the same surgery, in order to rehabilitate the edentulous area. The intervention was completed by tissue regeneration with biomaterials.

RESULTS

Prosthetic rehabilitation after the surgical phase allowed us to provide correct function and satisfactory esthetics. In the follow-up visit, clinicians found good tissue healing and did not observe any complications, such as implant loss or peri-implantitis. The technique used in our study is repeatable and predictable, but patient selection is very important for this type of protocol as the presence of contraindications can lead to failure. The photoacoustic effect exerted by this type of laser has been proven to be effective against many pathogens. Several authors have previously demonstrated the effectiveness of this technique.

CONCLUSIONS

Immediate implantation in infected sites decontaminated with Er,Cr:YSGG laser does not seem to contribute to an increased risk of failure; however, it is necessary to follow a certain set of protocols and procedures to prevent peri-implantitis and other complications.

Antimicrobial photodynamic therapy for the treatment of oral infections: A systematic review

Oral infection is a common clinical symptom. While antibiotics are widely employed as the primary treatment for oral diseases, the emergence of drug-resistant bacteria has necessitated the exploration of alternative therapeutic approaches. One such modality is antimicrobial photodynamic therapy (aPDT), which utilizes light and photosensitizers. Indeed, aPDT has been used alone or in combination with other treatment options dealing with periodontal disease for the elimination of biofilms from bacterial community to achieve bone formation and/or tissue regeneration. In this review article, in addition to factors affecting the efficacy of aPDT, various photosensitizers, the latest technology and perspectives on aPDT are discussed in detail. More importantly, the article emphasizes the novel design and clinical applications of photosensitizers, as well as the synergistic effects of chemical and biomolecules with aPDT to achieve the complete eradication of biofilms and even enhance the biological performance of tissues surrounding the treated oral area.

Immediate Response of Diode Laser on the Microbial Load in Subjects with Chronic Periodontitis

Background

Chronic periodontitis is the most common dental disease reported globally as well as in India. Periodontal pathogens are usually seen in samples of gingival tissues, crevicular blood, GCF (gingival crevicular fluid), and dental plaque. Apart from the conventional mechanical treatment, laser disinfection is a recent advancement that change shows greater efficacy in reducing the disease progression and changing the bacterial flora.

Aim

The present study aimed to assess the Immediate response of diode laser on the microbial load in subjects with chronic Periodontitis as assessed in saliva, crevicular blood, and GCF (gingival crevicular fluid) samples.

Materials and Methods

The study recruited 90 subjects with chronic periodontitis. For split-mouth fashion, the mouth, of each participant was divided into two halves and was divided into two groups randomly. Group I (test group) subjects underwent laser disinfection (970 ± 15 nm). Group II subjects served as controls and underwent saline irrigation. For all participants, crevicular blood, saliva, and GCF samples were collected before and immediately following disinfection for microbial analysis.

Results

Microbial load reduction was seen in both groups following treatment. However, a significantly higher reduction was seen in the test group with laser disinfection. Compared to the crevicular blood sample, a greater reduction was seen in saliva and GCF samples.

Conclusion

The present study concludes that Diode Laser (970 ± 15 nm) application shows an immediate reduction of the bacterial load in subjects with chronic periodontitis.

The Effects of Titanium Dioxide Nanoparticles on Osteoblasts Mineralization: A Comparison between 2D and 3D Cell Culture Models

Although several studies assess the biological effects of micro and titanium dioxide nanoparticles (TiO₂ NPs), the literature shows controversial results regarding their effect on bone cell behavior. Studies on the effects of nanoparticles on mammalian cells on two-dimensional (2D) cell cultures display several disadvantages, such as changes in cell morphology, function, and metabolism and fewer cell-cell contacts. This highlights the need to explore the effects of TiO₂ NPs in more complex 3D environments, to better mimic the bone microenvironment. This study aims to compare the differentiation and mineralized matrix production of human osteoblasts SAOS-2 in a monolayer or 3D models after exposure to different concentrations of TiO₂ NPs. Nanoparticles were characterized, and their internalization and effects on the SAOS-2 monolayer and 3D spheroid cells were evaluated with morphological analysis. The mineralization of human osteoblasts upon exposure to TiO₂ NPs was evaluated by alizarin red staining, demonstrating a dose-dependent increase in mineralized matrix in human primary osteoblasts and SAOS-2 both in the monolayer and 3D models. Furthermore, our results reveal that, after high exposure to TiO₂ NPs, the dose-dependent increase in the bone mineralized matrix in the 3D cells model is higher than in the 2D culture, showing a promising model to test the effect on bone osteointegration.

Comparison of clinical outcomes of non-surgical adjunctive use of the 980-nm diode laser to conventional periodontal flap procedure-a randomised controlled split-mouth clinical trial

Lasers have been found to be effective as an adjunctive in periodontal therapy. The objective of the study was to compare the outcomes of non-surgical adjunctive use of 980-nm diode laser to that of conventional flap surgery in terms of clinical outcome measures and radiographic osseous defect depths. This study was designed as a double-blinded split-mouth randomised controlled clinical trial. A total of fifteen patients (30 quadrants) with generalised periodontitis stage III grade B were randomly assigned test group (diode laser) and control group (conventional flap surgery). Both test and control groups had 15 quadrants each. At 3 months, the probing pocket depth (PPD) was 3.46 ± 0.19 mm (test) and 4.20 ± 0.20 mm (control), with a statistically significant difference between the groups (p = 0.01). Similarly, at 6 months re-evaluation, PPD was 1.46 ± 0.12 mm (test) and 2.33 ± 0.13 mm (control) with a highly significant statistical difference (p = 0.001). Plaque index showed a difference between both test and control groups at baseline, 3 months and 6 months (p = 0.001) while gingival index, modified sulcular bleeding index and radiographic osseous defect depth showed a difference at 3 months and 6 months (p = 0.001). Within the study's limitations, 980-nm diode laser can result in significant improvements in the clinical and radiographic parameters and is very well tolerated by the subjects.

Status of North American Graduate Programs in Periodontics Providing Laser Education and Clinical Training: A Cross-Sectional Survey

The aim of this cross-sectional study was to evaluate the status of laser use and training in the U.S. and Canadian graduate periodontology programs. A survey questionnaire was sent electronically to 55 periodontology program directors in North America. The questions focused on laser implementation, types of lasers used, for which procedures lasers were used, and level of education/clinical training provided to residents. Data were analyzed using descriptive statistics and Fisher’s exact test. Twenty-two directors responded (40%). Most programs (86%) used lasers and 89% used a diode laser. Laser treatment was the most used for periimplantitis (84%). Fifteen programs (79%) provided didactic and clinical training, with 47% programs giving 4–12 h of didactic training. In 53% of programs, residents completed 4 to10 procedures. Only 29% of programs had residents who had received a certification in lasers, with most (80%) programs requiring between 1–9 cases for certification. Of the participants not providing laser training, the major barrier was indicated as being “expense”, with 68.7% reporting plans to implement laser education. Conclusions: Most graduate periodontics programs were providing laser training and treatment. There was great variability regarding the training methods, specifically in number of dedicated laser courses, time allocated for laser training, and prerequisites for laser certification.

Effects of diode and erbium lasers as an adjunct to scaling and root planing on clinical and immunological parameters in non-surgical periodontal treatment: a split-mouth randomized controlled clinical trial-"effects of lasers on immunological parameters"

This study evaluated the effects of diode and erbium lasers, as an adjunct to scaling and root planing (SRP), on clinical and immunological parameters in non-surgical periodontal therapy. In this split-mouth randomized controlled clinical trial, 17 participants with at least one periodontally involved tooth in each quadrant received oral hygiene instruction and full-mouth SRP. At baseline, probing pocket depth (PPD), clinical attachment level (CAL), bleeding on probing (BOP), and full-mouth plaque index (FMPI) were measured, and gingival crevicular fluid (GCF) sampling was performed. Next, one random quadrant in each participant received 940 nm diode laser (1 W, continuous-wave), and another quadrant received 2780 nm Er,Cr:YSGG laser (1.5 W, 30 Hz) irradiation. The GCF levels of interleukin (IL)-10 and matrix metalloproteinase (MMP)-13 were measured at baseline, and after 2 and 6 months using ELISA. The clinical parameters were also measured. Data were analyzed by repeated measures ANOVA. Significant clinical improvement was noted in all groups (P < 0.05). CAL in the control group was higher at 6 months than 2 months. The increase in IL-10 in erbium group was significantly greater than that in other groups (P < 0.001). The MMP-13 level was significantly lower in laser groups with greater reduction in erbium group (P < 0.001). Application of 940 nm diode and 2780 nm Er,Cr:YSGG lasers as an adjunct to SRP significantly decreased the GCF level of MMP-13, with no significant clinical advantage over SRP monotherapy. Application of 2780 nm Er,Cr:YSGG laser in addition to SRP increased the GCF level of IL-10.Trial registration numbers: IRCT20140318017053N11 and IRCT20140318017053N9.

Laser-Assisted Management of a Rare Presentation of Peripheral Ossifying Fibroma in an Infant

Reactive hyperplasias are a group of lesions often seen in the oral mucosa, especially on the gingiva, in association with local irritation or trauma. Peripheral ossifying fibroma (POF) is a common reactive lesion, almost always affecting the tooth-bearing areas of the oral cavity. It is most often encountered in young adults but extremely rare in patients below 10 years of age. Here, we report a unique presentation of peripheral ossifying fibroma affecting the anterior mandible in a three-month-old infant. We also highlight the role of laser in the management of such lesions.

Comparative assessment between bio-adhesive material and silk suture in regard to healing, clinical attachment level and width of keratinized gingiva in gingival recession defects cases

The objective of this study was to compare the silk suture with a cyanoacrylate adhesive to stabilize the free gingival graft in conjunction with Er: YAG laser-assisted recipient site preparation to augment the keratinized tissue in gingival recession cases. This randomized trial comprised of 300 recession defects patients. All the included patients were diagnosed using Miller class I and II gingival recession defects classification. Group I sites were treated with a free gingival graft (FGG) harvested using an Er: YAG laser and further sutured with silk. Group II sites were stabilized with isoamyl 2 cyanoacrylate bio-adhesive material. Clinical parameters, such as gingival recession depth, clinical attachment level, gain in gingival tissue thickness, and width of keratinized gingiva were recorded at baseline, and at third month, sixth month, and 12th month postoperatively. The mean changes in gingival recession from months 3 to 6 and months and 6 to 12 were significant (p < 0.05) in both groups. However, the improvement in recession depth was better in group II than in group I. The mean change in clinical attachment level did not differ significantly between the groups at the different time intervals. However, values tended to be higher in group II than in group I. The width of the keratinized gingiva tended to be higher from baseline to 3 months, baseline to 6 months, baseline to 12 months, 3 to 6 months, and from 6 to 12 months in group II as compared with group I (p > 0.05). Cyanoacrylate could be used as a substitute to silk sutures to stabilize FGGs. Cyanoacrylate was easy to apply, consumed less operating time, and was considered equally efficacious for stabilizing FGGs.

Photobiomodulation in Endodontic, Restorative, and Prosthetic Dentistry: A Review of the Literature

Objective: To provide a review of the literature about the photobiomodulation therapy (PBMT) dental treatment protocols in endodontic, restorative, and prosthetic dentistry based on validated clinical studies published so far. More specifically, this study was carried out to carefully review therapeutic protocol of PBMT in clinical studies and their conclusions. Background data: The importance of using low-power lasers and photobiomodulation (PBM) is increasing in dentistry mainly due to their painless and noninvasive function. However, lack of sufficient clinical studies has led to unclear results regarding PBMT in dentistry, and also lack of an available precise protocol for clinicians. Moreover, scarcity of clinical studies in this area has made conduction of a precise systematic review study difficult. Methods: In our study, published clinical studies up to April 2019 were reviewed from library sources, Google Scholar, PubMed and Medline, Elsevier, Embase, Cochrane, Scopus, and Web of science (ISI). Inclusion criteria included those presented in clinical trials and case report/case series, language (English), and studies available in full text. Exclusion criterion was in vitro studies. Results: In general, findings of clinical studies have shown that PBMT can have a significant role in reducing postoperative dental pain, increasing depth of anesthesia, improving tooth hypersensitivity, reducing inflammation of the tissue, and helping wound healing. Conclusions: A review of clinical studies showed that the use of alternative or adjunctive PBMT is of great importance in controlling postoperative pain after endodontic treatments. In addition, evidence suggests that different parameters of light can be efficient in the treatment of tooth hypersensitivity. Nevertheless, lack of sufficient clinical studies and reliable results do not allow introducing a precise treatment protocol.

Management of massive peripheral ossifying fibroma using diode laser

Peripheral ossifying fibroma (POF) represents a non-neoplastic, reactive lesion of gingiva. The precise etiopathogenesis of POF is unclear; however, it is suggested to originate from the connective tissue of periodontal ligament. This lesion predominantly occurs in the maxillary anterior region. The standard treatment protocol involves surgical excision followed by the biopsy of lesion. The reactive nature and unpredictable course attribute to a high recurrence rate of the lesion; hence, proper postoperative monitoring and follow-up of the lesion are necessary. The present case was surgically managed using diode laser and did not show any sign of recurrence during the follow-up period of 6 months. Minimum intraoperative bleeding and postoperative pain, ease of operation, and patient's acceptance enable laser-assisted growth excision as a better treatment modality to other conventional surgical procedures, thus offering diode laser as a viable and effective treatment alternative in the management of massive overgrowth.

Decontamination of Dental Implant Surfaces by the Er:YAG Laser Beam: A Comparative in Vitro Study of Various Protocols

Oral rehabilitation with dental implants has revolutionized the field of dentistry and has been proven to be an effective procedure. However, the incidence of peri-implantitis has become an emerging concern. The efficacy of the decontamination of the implant surface, by means of lasers, is still controversial. Previous studies have revealed a reduction in osteoblast adhesion to carbon-contaminated implant surfaces. This in-vitro study aimed to evaluate the decontamination of failed implants by assessing the carbon proportion, after irradiation by low-energy erbium yttrium-aluminum-garnet laser (Er:YAG) (Fotona; 2940 nm, Ljubljana, Slovenia) for a single and for multiple passages, until getting a surface, free of organic matters; to find the appropriate procedure for dental-implant surface-decontamination. Ninety implants were used. Thirty sterile implants were kept as a negative control. Thirty failed implants were irradiated by the Er:YAG laser, for a single passage, and the other thirty, for multiple passages. The parameters used in our experiments were an irradiation energy of 50 mJ, frequency of 30 Hz, and an energy density of 3.76 J/cm². A sapphire tip, with a length of 8 mm, was used with concomitant water spray irrigation, under air 6 and water spray 4. Super short pulse mode (SSP) was of 50 μs; irradiation speed being 2 mm/s. We used energy-dispersive X-ray spectroscopy (EDX) to evaluate the carbon proportion on the surfaces of the sterile implants, the contaminated, and the lased implants, with one (LX1) and with three passages (LX3). Statistical analysis was performed by ANOVA. Results showed mean difference between the three groups (contaminated, LX1, and LX3) with p < 0.0001, as between LX1 and Group A (p < 0.0001), while the difference between LX3 and the control group was not statistically significant. The decontamination of the implant surfaces with a low-energy Er:YAG laser with three passages, appeared to be an encouraging approach.

Assessment of microleakage of class V restored by resin composite and resin-modified glass ionomer and pit and fissure resin-based sealants following Er:YAG laser conditioning and acid etching: in vitro study

Aim

The aim of this study was to make a comparison between microleakage of conventionally restored class V cavities using acid etchant and the ones conditioned by erbium-doped yttrium aluminum garnet (Er:YAG) laser, and also to assess and compare the effectiveness of enamel surface treatments of occlusal pits and fissures by acid etching and conditioned by Er:YAG laser-etch.

Materials and methods

Seventy-two extracted third molars were used in this study. The samples were divided into two major groups: class V cavities and pit and fissure sealants. Each subgroup was divided into conventional acid etching, Er:YAG laser conditioning and conventional acid etching, and combination with Er:YAG laser conditioning (n=12). The teeth were placed in 2% methylene blue dye solution, were sectioned, and were evaluated according to the dye penetration criteria. Two samples per subgroup were chosen for scanning electron microscopic (SEM) analysis.

Results

There was a significant difference between occlusal and cervical margin groups. Laser conventional composite cementum group showed more microleakage values compared to other groups. There was no significant difference between occlusal margin groups. However, there was a significant difference between cervical margin groups in terms of microleakage. In sealant groups, there was a significant difference between laser and conventional with/without laser treatment groups in terms of microleakage.

Conclusion

Based on the results reported in this study, it can be concluded that the application of the Er:YAG laser beneath the resin composite, the resin-modified glass ionomers (GIs), and the fissure sealant placement may be an alternative enamel and dentin etching method to acid etching.

The effects of the Er:YAG laser on trabecular bone micro-architecture: Comparison with conventional dental drilling by micro-computed tomographic and histological techniques

Background: The use of lasers has become increasingly common in the field of medicine and dentistry, and there is a growing need for a deeper understanding of the procedure and its effects on tissue. The aim of this study was to compare the erbium-doped yttrium aluminium garnet (Er:YAG) laser and conventional drilling techniques, by observing the effects on trabecular bone microarchitecture and the extent of thermal and mechanical damage.

Methods: Ovine femoral heads were employed to mimic maxillofacial trabecular bone, and cylindrical osteotomies were generated to mimic implant bed preparation. Various laser parameters were tested, as well as a conventional dental drilling technique. The specimens were then subjected to micro-computed tomographic (μCT) histomorphometic analysis and histology.

Results: Herein, we demonstrate that mCT measurements of trabecular porosity provide quantitative evidence that laser-mediated cutting preserves the trabecular architecture and reduces thermal and mechanical damage at the margins of the cut. We confirmed these observations with histological studies. In contrast with laser-mediated cutting, conventional drilling resulted in trabecular collapse, reduction of porosity at the margin of the cut and histological signs of thermal damage.

Conclusions: This study has demonstrated, for the first time, that mCT and quantification of porosity at the margin of the cut provides a quantitative insight into damage caused by bone cutting techniques. We further show that with laser-mediated cutting, the marrow remains exposed to the margins of the cut, facilitating cellular infiltration and likely accelerating healing. However, with drilling, trabecular collapse and thermal damage is likely to delay healing by restricting the passage of cells to the site of injury and causing localized cell death.

Mesenchymal stromal cell and osteoblast responses to oxidized titanium surfaces pre-treated with λ = 808 nm GaAlAs diode laser or chlorhexidine: in vitro study

Preservation of implant biocompatibility following peri-implantitis treatments is a crucial issue in odontostomatological practice, being closely linked to implant re-osseointegration. Our aim was to assess the responses of osteoblast-like Saos2 cells and adult human bone marrow-mesenchymal stromal cells (MSCs) to oxidized titanium surfaces (TiUnite^®, TiU) pre-treated with a 808 ± 10 nm GaAlAs diode laser operating in non-contact mode, in continuous (2 W, 400 J/cm²; CW) or pulsed (20 kHz, 7 μs, 0.44 W, 88 J/cm²; PW) wave, previously demonstrated to have a strong bactericidal effect and proposed as optional treatment for peri-implantitis. The biocompatibility of TiU surfaces pre-treated with chlorhexidine digluconate (CHX) was also evaluated. In particular, in order to mimic the in vivo approach, TiU surfaces were pre-treated with CHX (0.2%, 5 min); CHX and rinse; and CHX, rinse and air drying. In some experiments, the cells were cultured on untreated TiU before being exposed to CHX. Cell viability (MTS assay), proliferation (EdU incorporation assay; Ki67 confocal immunofluorescence analysis), adhesion (morphological analysis of actin cytoskeleton organization), and osteogenic differentiation (osteopontin confocal immunofluorescence analysis; mineralized bone-like nodule formation) analyses were performed. CHX resulted cytotoxic in all experimental conditions. Diode laser irradiation preserved TiU surface biocompatibility. Notably, laser treatment appeared even to improve the known osteoconductive properties of TiU surfaces. Within the limitations of an in vitro experimentation, this study contributes to provide additional experimental basis to support the potential use of 808 ± 10 nm GaAlAs diode laser at the indicated irradiation setting, in the treatment of peri-implantitis and to discourage the use of CHX.

Commentary: Is There Clinical Benefit From Using a Diode or Neodymium:Yttrium-Aluminum-Garnet Laser in the Treatment of Periodontitis?

Despite a quarter of a century of laser research, there is a persistent debate regarding the efficacy of dental lasers in the treatment of periodontitis or periodontal maintenance therapy. There are many claims and much hyperbole surrounding the use of lasers, either as a monotherapy or adjunctive to scaling and root planing, to treat periodontitis. There is little evidence that using a diode or neodymium:yttrium-aluminum-garnet laser adds clinical value over and above conventional non-surgical or surgical periodontal treatment. There is a significant need for better designed human clinical trials. Data from such trials should be analyzed according to initial probing depth and characteristics of the treated sites, such as non-molar, molar flat surfaces, and molar furcations, and evaluated for long-term post-treatment results.