Biopsy of different oral soft tissues lesions by KTP and diode laser: histological evaluation.

INTRODUCTION: Oral biopsy aims to obtain clear and safe diagnosis; it can be performed by scalpel or laser. The controversy in this latter application is the thermal alteration due to tissue heating. The aim of this study is the histological evaluation of margins of "in vivo" biopsies collected by diode and KTP lasers. MATERIAL AND METHODS: 17 oral benign lesions biopsies were made by diode 808 nm (SOL, DenMatItalia, Italy) and KTP 532 nm (SmartLite, DEKA, Italy). Samples were observed at OM LEICA DM 2000; margin alterations were evaluated through Leica Application Suite 3.4. RESULTS: Epithelial and connective damages were assessed for each pathology with an average of 0.245 mm and a standard deviation of ± 0.162 mm in mucoceles, 0.382 mm ± 0.149 mm in fibromas, 0.336 mm ± 0.106 mm in hyperkeratosis, 0.473 mm ± 0.105 mm in squamous hyperplasia, 0.182 mm in giant cell granuloma, and 0.149 mm in melanotic macula. DISCUSSION: The histologic aspect of lesions influenced the response to laser, whereas the greater inflammation and cellularity were linked with the higher thermal signs. Many artifacts were also associated to histologic procedures. CONCLUSION: Both tested lasers permitted sure histologic diagnosis. However, it is suggested to enlarge biopsies of about 0.5 mm, to avoid thermal alterations, especially in inflammatory lesions like oral lichen planus.

Photon-Induced Photo-Acoustic Streaming vs. Shock Wave-Enhanced Emission Photo-Acoustic Streaming-The Effect of Three Final Irrigation Protocols on the Bond Strength of an Individually Formed Fiber Post.

(1) Background: This study aimed to evaluate how laser-activated irrigation (LAI) influences the retention of a fiber post when used before an endodontic filling, as well as after post space preparation. (2) Materials and Methods: Sixty freshly extracted human incisors were selected. The teeth were randomly assigned to three groups-CONVENTIONAL (CONV), PIPS or SWEEPS-and treated endodontically. Each group received irrigation with 1 × 5 mL EDTA (17%) and 3 × 5 mL NaOCl (5.25%). In the first group, the irrigants were not activated, while in the second and third group, LAI was adopted using PIPS and SWEEPS protocols (Lightwalker from Fotona, Ljubliana, Slovenia). After post space preparation, each group received the same irrigation protocol initially established. Sticky posts (everStick Post, GC AUSTRIA GmbH Swiss) were individually adapted to the corresponding post spaces and cemented using dual cure resin cement (Gradia Core, GC Austria GmbH Swiss). All specimens were vertically embedded into self-curing acrylate (Duracryl plus, Spofa Dent, Europe), and each was sectioned into three segments of type A and type B samples for debonding through push-out and pull-out tests. The results were statistically analyzed. (3) Results: The pull-out test showed the superiority of the SWEEPS group, with a mean fracture force of 133.0 ± 50.7 N, followed by the PIPS group, with 102 N, with a lower standard deviation of ± 34.5 N. The CONV group registered the lowest fracture force. Concerning the push-out test, the SWEEPS group showed superior shear stress in comparison to the other two groups (13.45 ± 4.29 MPa); the CONV group was inferior, with shear tension values of 8.31 ± 4.67 MPa. (4) Conclusions: It can be stated that the SWEEPS and PIPS protocols resulted in considerably higher fiber post retention than the conventional method, whereas the SWEEPS protocol was superior to the PIPS protocol.

Laser treatment of 13 benign oral vascular lesions by three different surgical techniques.

OBJECTIVES: Benign Oral Vascular Lesions (BOVLs) are a group of vascular diseases characterized by congenital, inflammatory or neoplastic vascular dilations clinically evidenced as more or less wide masses of commonly dark bluish color. If traumatized BOVLs are characterized by a great risk of hemorrhage and their treatment usually requires great caution to prevent massive bleeding. In the last decades lasers have dramatically changed the way of treatment of BOVLs permitting the application of even peculiar techniques that gave interesting advantages in their management reducing hemorrhage risks. The aim of this study was to evaluate the capabilities and disadvantages of three laser assisted techniques in the management of BOVLs. STUDY DESIGN: In this study 13 BOVLs were treated by three different laser techniques: the traditional excisional biopsy (EB), and two less invasive techniques, the transmucosal thermocoagulation (TMT) and the intralesional photocoagulation (ILP). Two different laser devices were adopted in the study: a KTP laser (DEKA, Florence, Italy, 532 nm) and a GaAlAs laser (Laser Innovation, Castelgandolfo, Italy, 808 nm) selected since their great effectiveness on hemoglobin. RESULTS: In each case, lasers permitted safe treatments of BOVLs without hemorrhages, both during the intervention and in the post-operative period. The minimally invasive techniques (TMT and ILP) permitted even the safe resolution of big lesions without tissue loss. CONCLUSIONS: Laser devices confirm to be the gold standard in BOVLs treatment, permitting even the introduction of minimal invasive surgery principles and reducing the risks of hemorrhage typical of these neoplasms. As usual in laser surgery, it is necessary a clear knowledge of the devices and of the laser-tissue interaction to optimize the results reducing risks and disadvantages.

SEM Evaluation of Thermal Effects Produced by a 445 nm Laser on Implant Surfaces.

The aim of this in vitro study was to evaluate thermal effects on implant surfaces using a 445 nm diode laser (Eltech K-Laser Srl, Treviso, Italy) with different power settings and irradiation modalities. Fifteen new implants (Straumann, Basel, Switzerland) were irradiated to evaluate surface alteration. Each implant was divided into two zones: the anterior and posterior areas. The anterior coronal areas were irradiated with a distance of 1 mm between the optical fiber and the implant; the anterior apical ones were irradiated with the fiber in contact with the implant. Instead, the posterior surfaces of all of the implants were not irradiated and used as control surfaces. The protocol comprised two cycles of laser irradiation, lasting 30 s each, with a one-minute pause between them. Different power settings were tested: a 0.5 W pulsed beam (T-on 25 ms; T-off 25 ms), a 2 W continuous beam and a 3 W continuous beam. Lastly, through a scanning electron microscopy (SEM) analysis, dental implants' surfaces were evaluated to investigate surface alterations. No surface alterations were detected using a 0.5 W laser beam with a pulsed mode at a distance of 1 mm. Using powers of irradiation of 2 W and 3 W with a continuous mode at 1 mm from the implant caused damage on the titanium surfaces. After the irradiation protocol was changed to using the fiber in contact with the implant, the surface alterations increased highly compared to the non-contact irradiation modality. The SEM results suggest that a power of irradiation of 0.5 W with a pulsed laser light emission mode, using an inactivated optical fiber placed 1 mm away from the implant, could be used in the treatment of peri-implantitis, since no implant surface alterations were detected.

Comparison of Two Root Canal Filling Techniques: Obturation with Guttacore Carrier Based System and Obturation with Guttaflow2 Fluid Gutta-Percha.

INTRODUCTION: The aim of the present study was to compare the quality of the root canal obturation obtained with two different techniques, i.e., thermoplastic gutta-percha introduced through a carrier (GuttaCore) and fluid gutta-percha (GuttaFlow2). MATERIALS AND METHODS: The study included 40 permanent single-rooted human teeth, divided into two groups and obturated with Guttaflow (group G) and with GuttaCore (group T). The teeth were fixed and transversely sectioned, they were examined by scanning electron microscopy. The dentin-cement-gutta-percha interface and the percentage of voids produced by the two techniques were statistically analyzed. RESULTS: GuttaCore showed a better filling in the apical third of the canal with a percentage of voids equal to 5%. GuttaFlow showed a lower percentage of voids in the middle and coronal thirds of the canal, 1.6% of coronal voids. Statistical analysis showed a statistically significant difference in the percentage of voids in the two groups (GuttaCore and Guttaflow2) in each portion. CONCLUSIONS: GuttaFlow2 seems to flow optimally in the middle and coronal third of the canal, with greater difficulty in filling the apical third. Due to the rigidity of the carrier, GuttaCore is able to reach better the most apical portions of the canals, with greater difficulty in creating the three-dimensional seal at the level of the middle third and coronal third.

Evaluation of the efficacy of a new low-level laser therapy home protocol in the treatment of temporomandibular joint disorder-related pain: A randomized, double-blind, placebo-controlled clinical trial.

Objective: This study analyzed a home, low-level laser therapy (LLLT) protocol to manage temporomandibular joint disorders (TMJDs)-related pain.Methods: Ninety TMJD patients (12M, 78F) between 18 and 73 years were randomly subdivided into three groups. Study group (SG) received 1-week home protocol LLLT by B-cure Dental Pro: 808 nm, 5 J/min, 250 mW, 15 KHz for 8', 40 J each, over pain area, twice daily. Placebo group (PG) followed the same protocol using sham devices. Drugs group (DG) received conventional drugs. Pain was evaluated by visual analog scale (VAS) before and after therapy.Results: Statistical analysis showed that treatment was effective (F(2,83) = 4.882; p = .010). Bonferroni post-hoc analysis indicated a lower pain decrease in PG. SG registered a 34-point decrease per patient, while in PG and DG, the reduction was 25.6 and 35.3, respectively.Conclusion: The study supports the efficacy of home LLLT management of TMJD related pain.

Disinfection of Root Canals with Laser-Activated Irrigation, Photoactivated Disinfection, and Combined Laser Techniques: An Ex Vivo Preliminary Study.

Objective: This study aimed to evaluate the efficacy of laser-activated irrigation using photon-induced photoacoustic streaming (PIPS®) and photoactivated disinfection (PAD) techniques and their combination to improve penetration and activation of toluidine blue in the endodontic space of teeth experimentally infected with Enterococcus faecalis. Materials and methods: Twenty-seven extracted single-root teeth were instrumented, sterilized, and infected with E. faecalis and divided into seven groups of three teeth each: Group A [sodium hypochlorite (NaClO) 5% hand irrigation], Group B [NaClO 5% hand irrigation+ethylenediaminetetraacetic acid (EDTA)+NaClO 5% activated by PIPS], Group C (EDTA+NaClO 5% activated by PIPS), Group D (toluidine blue activated by PAD), Group E (toluidine blue activated by PIPS and PAD), Group F (NaClO 5% hand irrigation+toluidine blue activated by PAD), and Group G (NaClO 5% hand irrigation+toluidine blue activated by PIPS and PAD). Finally, positive and negative group controls were prepared. The presence of biofilms after the treatments was assessed by the BioTimer assay. PIPS was performed with an Er:YAG laser (2940 nm, LightWalker, Fotona® d.o.o., Slovenia) at 20 mJ, 15 Hz, 0.3 W, and 50-µs pulse duration. PAD was performed with a 635 nm diode laser (Smart M, Lasotronix®, Poland) at 400 mW in continuous wave (CW). Results: When NaClO was used, significant decontamination (p ≤ 0.05) was obtained in all experimental groups with respect to the positive control, other than Group G. Irrigation with EDTA+NaClO activated by PIPS produced a higher level of decontamination than Group A (p ≤ 0.05). Significant results in reducing biofilm load compared with the control and Group A were observed when NaClO was coupled with toluidine blue activated by PAD (p ≤ 0.05). Conclusions: Disinfection of root canals can be obtained using a combination of different irrigants, photosensitizers, and activation protocols. EDTA+NaClO using the PIPS protocol and toluidine blue activated by PAD (both preceded by NaClO irrigation) can be considered effective tools. The possibility of replacing NaClO with toluidine blue, whatever the method of activation, should be further investigated.

Comparison of the Effects of Photobiomodulation with Different Lasers on Orthodontic Movement and Reduction of the Treatment Time with Fixed Appliances in Novel Scientific Reports: A Systematic Review with Meta-Analysis.

Background: The duration of orthodontic treatment is one of the most important aspects considered by patients. Photobiomodulation (PBM) depends upon the exposure of the tissue to particular, therapeutic wavelengths of light in the "therapeutic window" (from 600 to 1200 nm). PBM increases cell metabolism, which leads to higher ATP production. Increasing the amount of ATP in well-vascularized bone cells promotes cell proliferation and differentiation, creating a favorable environment for tooth movement. Objective: The aim of the study is to discuss and compare the use of PBM in accelerating the orthodontic movement and reducing the time of treatment. Materials and methods: A systematic review was conducted. Literature searches were performed using Medline (PubMed), Web of Science, and Scopus (from September 13 to September 20, 2019). The quality assessment was performed using the Jadad scale for reporting randomized controlled trials for randomized clinical trial and randomized control clinical trial studies, and the Newcastle/Ottawa Quality Assessment Form for case/control studies. Results: Thirty-three articles from PubMed, 46 from Scopus, 5 from Web of Science were selected. After removal of duplicates, 82 articles were analyzed. Subsequently, 74 articles were excluded because they did not meet the inclusion criteria. The remaining eight articles were included in the qualitative synthesis. Conclusions and summary: PBM is an efficient, effective, and noninvasive method to accelerate orthodontic tooth movement. PBM should be introduced into the daily practice of treating various malocclusions as an additional procedure. Intraoral application gives better results and its introduction to treatment seems more reasonable.

Effectiveness of KTP laser versus 980 nm diode laser to kill Enterococcus faecalis in biofilms developed in experimentally infected root canals.

This study aimed to evaluate the antibacterial action of KTP (potassium-titanyl-phosphate) laser irradiations (compared with 980 nm diode laser), associated with conventional endodontic procedures, on Enterococcus faecalis biofilms. Fifty-six dental roots with single canals were prepared with Ni-Ti rotary instruments, autoclaved, inoculated with an E. faecalis suspension and incubated for 72 h. They were randomly allocated to control and treatment groups. Laser parameters were as follows: power 2.5 W, Ton 35 ms, Toff 50 ms (KTP laser); power 2.5 W, Ton 30 ms, Toff 30 ms (980 nm diode laser). To evaluate the residual bacterial load, BioTimer Assay was employed. The chemo-mechanical treatment together with laser irradiations (KTP and 980 nm diode lasers) achieved a considerable reduction of bacterial load (higher than 96% and 93%, respectively). Regarding both laser systems, comparisons with conventional endodontic procedures (mortality rate of about 67%) revealed statistically highly significant differences (P ≤ 0.01). This study confirms that laser systems can provide an additional aid in endodontic disinfection.

Enamel pearls as a predisposing factor to localized periodontitis.

Enamel pearls are enamel anomalies on primary and permanent teeth roots that usually appear at furcation areas, especially in maxillary second and third molars. Enamel pearls usually occur singularly, but as many as four have been observed on the same tooth. This report describes an unusual case of multiple enamel pearls associated with periodontal pockets localized on all maxillary first and second molars. Because the patient had an advanced stage of periodontitis, the maxillary right first and left second molars were extracted. The remaining two maxillary molars were included in a strict follow-up protocol. Enamel pearls were confirmed as the cause of localized periodontitis; therefore, it is very important to recognize their radiologic aspect to ensure proper treatment of the involved teeth.

The low level laser therapy in the management of neurological burning mouth syndrome. A pilot study.

BACKGROUND AND OBJECTIVE: Burning Mouth Syndrome (BMS) is a common disease but still a diagnostic and therapeutic challenge for clinicians. Despite many studies its nature remains obscure and controversial; nowadays there is no consensus about definition, diagnosis and classification. BMS is characterized clinically by burning sensations in the tongue or other oral sites, often without clinical and laboratory findings. According to the etiology, BMS cases should be subdivided into three subtypes: BMS by local factors (lfBMS), BMS by systemic factors (sfBMS) and neurological BMS (nBMS), the most frequent, in which the symptom is caused by central or peripheral neurological malfunctions affecting in particular the taste pathway. To establish the type of BMS, both anamnesis and clinical examination, including laboratory tests, are necessary; nBMS cases will be recognized by exclusion of any other type. In case of lfBMS or sfBMS, the treatment of the main pathology will be resolutive; in nBMS cases many Authors proposed different pharmacological trials without satisfactory results and the current opinion is that a multidisciplinary approach is required to keep the condition under control. This pilot study aimed to investigate whether the biostimulative effect of Low Level Laser Therapy (LLLT) could enhance the symptoms of nBMS cases, improving patients' quality of life. STUDY DESIGN/MATERIALS AND METHODS: Among 160 patients affected by oral burning sensation attending to the Oral Pathology Complex Operative Unit of the Department of Stomatological Sciences of Sapienza University of Rome, 77 resulted affected by nBMS. Twenty-five of these patients, 16 females and 9 males, were randomly selected for low level laser applications. All the patients were irradiated with a double diode laser (Lumix 2 Prodent, Italy) emitting contemporarily at 650 nm and 910 nm, with a fluence of 0.53 J/cm(2) for 15 minutes twice a week for 4 weeks. The areas of irradiation were the sides of the tongue on the path of taste fibers. A NRS (numerical rating scale) evaluation of maximum and minimum pain was registered before and after the treatment. In each case to the total value of NRS rates registered before the treatment was deducted the total NRS rate registered after the treatment. The difference was estimated effective if over two points. The Kruskall-Wallis test revealed the significance of the study (p<0.0001) and the Dunn's Multiple Comparison test, applied to compare NRS rates before and after the treatment, showed that there is not a statistically relevant difference between min NRS ratings before and after treatment, while there are statistically significant differences between max NRS ratings (p<0.05). RESULTS: All the patients agreed the treatment confirming the general good compliance related to laser treatments. No side effects were registered and all the patients completed the therapy without interruption. Seventeen patients (68%) had relevant benefits from the treatment with valid reduction of NRS ratings. In 8 cases the differences of NRS rates were not relevant being under the limit of reliability established in study design. In no case there was a worsening of the symptoms. CONCLUSIONS: According to the results of this pilot study it is reasonable to suppose that LLLT may play an important role in the management of nBMS cases, more investigations are needed to clarify, by a greater number of cases and a placebo control group, the real effectiveness of this innovative LLLT application.

Bone damage induced by different cutting instruments--an in vitro study.

The aim of this study was to compare the peripheral bone damage induced by different cutting systems. Four devices were tested: Er:YAG laser (2.94 mm), Piezosurgery, high-speed drill and low-speed drill. Forty-five bone sections, divided into 9 groups according to different parameters, were taken from pig mandibles within 1 h post mortem. Specimens were fixed in 10% buffered formalin, decalcified and cut in thin sections. Four different parameters were analyzed: cut precision, depth of incision, peripheral carbonization and presence of bone fragments. For statistical analysis, the Kruskal-Wallis test was applied to assess equality of sample medians among groups. All sections obtained with the Er:YAG laser showed poor peripheral carbonization. The edges of the incisions were always well-shaped and regular, no melting was observed. Piezosurgery specimens revealed superficial incisions without thermal damage but with irregular edges. The sections obtained by traditional drilling showed poor peripheral carbonization, especially if obtained at lower speed. There was statistically significant differences (p<0.01) among the cutting systems for all analyzed parameters. Er:YAG laser, gave poor peripheral carbonization, and may be considered an effective method in oral bone biopsies and permits to obtain clear and readable tissue specimens.

Bone damage induced by different cutting instruments: an in vitro study

The aim of this study was to compare the peripheral bone damage induced by different cutting systems. Four devices were tested: Er:YAG laser (2.94 mm), Piezosurgery, high-speed drill and low-speed drill. Forty-five bone sections, divided into 9 groups according to different parameters, were taken from pig mandibles within 1 h post mortem. Specimens were fixed in 10 percent buffered formalin, decalcified and cut in thin sections. Four different parameters were analyzed: cut precision, depth of incision, peripheral carbonization and presence of bone fragments. For statistical analysis, the Kruskal-Wallis test was applied to assess equality of sample medians among groups. All sections obtained with the Er:YAG laser showed poor peripheral carbonization. The edges of the incisions were always well-shaped and regular, no melting was observed. Piezosurgery specimens revealed superficial incisions without thermal damage but with irregular edges. The sections obtained by traditional drilling showed poor peripheral carbonization, especially if obtained at lower speed. There was statistically significant differences (p<0.01) among the cutting systems for all analyzed parameters. Er:YAG laser, gave poor peripheral carbonization, and may be considered an effective method in oral bone biopsies and permits to obtain clear and readable tissue specimens.

O objetivo deste estudo foi comparar o dano ósseo periférico produzido por diversos sistemas de corte. Foram avaliados 4 dispositivos: laser Er:YAG (2,94 mm), Piezo-cirurgia, broca em alta rotação e broca em baixa rotação. Para isto, foram utilizadas 45 seções ósseas retiradas de mandíbulas de suínos, até 1 h post-mortem, divididas em 9 grupos de acordo com diversos parâmetros. As amostras foram fixadas em formalina a 10 por cento tamponada, descalcificadas e cortadas em lâminas finas. Foram analisados 4 parâmetros diferentes: a precisão do corte, a profundidade da incisão, a carbonização periférica e presença de fragmentos ósseos. A análise estatística empregou o teste de Kruskal-Wallis para avaliar a similaridade das medianas entre os grupos. Todas as seções feitas com o laser Er:YAG exibiram pouca carbonização. As margens das incisões foram todas bem acabadas e regulares, sem apresentar pontos de fusão. As amostras obtidas por piezo-cirurgia apresentaram incisões superficiais sem danos térmicos, mas com margens irregulares. As seções obtidas pelas brocas convencionais apresentaram pouca carbonização marginal, particularmente as feitas em baixa rotação. Foram observadas diferenças estatisticamente significantes (p<0,01) entre todos os sistemas de corte para cada um dos parâmetros analisados. O laser Er:YAG apresentou pouca carbonização e pode ser considerado como um método eficaz para biópsias de ossos bucais, produzindo amostras de tecido limpas e fáceis de analisar.