Comparison of the effect of hand instruments, an ultrasonic scaler, and an erbium-doped yttrium aluminium garnet laser on root surface roughness of teeth with periodontitis: a profilometer study

Root surface roughness evaluation following application of different periodontal instruments and Er:YAG laser: A profilometry and SEM study

AIM

The aim of the present study was to evaluate the efficacy of 30°-angled Er:YAG laser tip and different periodontal instruments on root surface roughness and morphology in vitro.

METHODS

Eighteen bovine teeth root without carious lesion were decoronated from the cementoenamel junction and seperated longitidunally. A total of 36 obtained blocks were mounted in resin blocks and polished with silicon carbide papers under water irrigation. These blocks were randomly assigned into 3 treatment groups. In Group 1, 30°-angled Er:YAG laser (2.94 μm) tip was applied onto the blocks with a 20 Hz, 120 mJ energy output under water irrigation for 20 s. In Groups 2 and 3, the same treatment was applied to the blocks with new generation ultrasonic tip and conventional curette apico-coronally for 20 s with a sweeping motion. Surface roughness and morphology were evaluated before and after instrumentation with a profilometer and SEM, respectively.

RESULTS

After instrumentation, profilometric analysis revealed significantly higher roughness values compared to baseline in all treatment groups(p < 0.05). Laser group revealed the roughest surface morphology followed by conventional curette and new generation ultrasonic tip treatment groups (p < 0.05). In SEM analysis, irregular surfaces and crater defects were seen more frequently in the laser group.

CONCLUSION

Results of the study showed that the use of new generation ultrasonic tip was associated with smoother surface morphology compared to 30°-angled Er-YAG laser tip and conventional curette. Further in vitro and in vivo studies with an increased sample size are necessary to support the present study findings.

Comparison of the Treatment Efficacy of Endo-Perio Lesions Using a Standard Treatment Protocol and Extended by Using a Diode Laser (940 nm)

Marginal and periapical periodontal diseases cause massive destruction of tooth tissues and surrounding tissues, such as alveolar bone and maxillary sinus floor, visible on radiographs. Lesions involving the apical and marginal periodontium are endo-perio (EPL) lesions. This study aimed to compare the treatment efficacy of endo-perio lesions using a standard treatment protocol and a standard diode laser-assisted treatment protocol. The 12 patients were divided into the study (a) and control (b) group. Periodontal indices, tooth vitality and mobility, occlusal status, and radiographic diagnosis were evaluated. Standard EPL treatment was then performed-without (a) and with (b) the use of diode laser (940 nm). Again, after six months, the above-mentioned parameters were evaluated and compared. The treatment of endo-perio lesions is a significant challenge for modern dentistry. Diode lasers are increasingly used in addition to traditional treatment methods. The conventional use of a 940 nm diode laser with an average power of 0.8 W in pulsed mode allows for the depth of periodontal pockets to be reduced. In addition, the use of a diode laser has a significant effect on tooth mobility and reduces bone loss.

Engineering Electrospun Nanofibers for the Treatment of Oral Diseases

With the increase of consumption of high-sugar foods, beverages, tobacco, and alcohol, the incidence rate of oral diseases has been increasing year by year. Statistics showed that the prevalence of oral diseases such as dental caries, dental pulpal disease, and periodontal disease has reached as high as 97% in 2015 in China. It is thus urgent to develop functional materials or products for the treatment of oral diseases. Electrospinning has been a widely used technology that is capable of utilizing polymer solution to generate micro/nano fibers under an appropriate high voltage condition. Owing to their excellent structures and biological performances, materials prepared by electrospinning technology have been used for a wide range of oral-related applications, such as tissue restoration, controlled drug release, anti-cancer, etc. In this regard, this article reviews the application and progress of electrospun nanofibers to various oral diseases in recent years. Firstly, engineering strategies of a variety of nanofiber structures together with their resultant functions will be introduced. Then, biological functions of electrospun nanofibers as well as their applications in the treatment of oral diseases are summarized and demonstrated. Finally, the development viewpoint of functional nanofibers is prospected, which is expected to lay the foundation and propose the direction for further clinical application.

Effect of desensitizing agents on dentin hypersensitivity after non-surgical periodontal therapy: A systematic review and meta-analysis

OBJECTIVE

To investigate the effectiveness of desensitizing agents (DA) on dentin hypersensitivity (DH) after non-surgical periodontal treatment (NSPT) through a systematic review and meta-analysis.

DATA

The PICO strategy was used to include randomized clinical trials in human subjects with DH (P) after NSPT treated with DA (I) compared to those treated with placebo or control (C) to identify DH relief (O). The Cochrane guidelines and GRADE was used to classify the risk of bias and the quality of the evidence, respectively.

SOURCES

PubMed, Web of Science, Scopus, Lilacs, Cochrane Library databases, and OpenGrey were searched on the 20^th of May 2020.

STUDY SELECTION

Nine studies were included in the quantitative synthesis. Five meta-analyses were performed. Three meta-analyzes assessed the effectiveness of DA compared to a placebo or control in relation to pain assessment stimuli and two meta-analyzes assessed the mechanism of action of DA. For the mechanical stimulus in overall analysis, the control group presented a higher mean of pain reduction (SMD 1.03 [0.73, 1.32], p < 0.001) with very low certainty of evidence. For water (SMD -0.78 [-1.22, -0.35], p = 0.0009) and evaporative in overall analysis (SMD -1.21 [-1.79, -0.64], p < 0.001) stimuli, the DA decreased DH pain with very low and low certainty of evidence, respectively.

CONCLUSION

Due to the limited quality of evidence, there is no definitive conclusion on the effectiveness of DA on DH after NSPT. Thus, further clinical studies with a low risk of bias and high-quality evidence are encouraged to reinforce the certainty of evidence on that issue.

CLINICAL SIGNIFICANCE

The use of desensitizing agents show promise for relief of dentin hypersensitivity after non-surgical periodontal therapy.

Calculus Removal and Root Surface Roughness When Using the Er:YAG or Er,Cr:YSGG Laser Compared with Conventional Instrumentation Method: A Literature Review

Objective: The purpose of this literature review was to evaluate the effectiveness of using Er:YAG (erbium-doped yttrium/aluminum/garnet) laser or Er,Cr:YSGG (erbium, chromium-doped yttrium/scandium/gallium/garnet) laser on calculus removal and their effect on the topography and roughness of root surface in comparison with the conventional instruments in the nonsurgical periodontal therapy. Background data: One of the most challenging problems in treatment of periodontal disease is the elimination of plaque and calculus, leaving a clean and smooth root surface to decrease plaque and calculus retention, and for good gingival reattachment. Materials and methods: PubMed and Google Scholar were searched for available literature. The electronic search was limited to articles published in the period between January 2007 and April 2017, in the English language. Results: A total of 47 publications fulfilled the inclusion criteria of this systematic review and screened according to the research questions. Calculus removal using the ultrasonic instrument showed remaining calculus compared with the hand instrument, whereas, on the contrary, erbium lasers revealed no remaining calculus or smaller amounts compared with the conventional instruments when used in appropriate settings. The results of this review showed that ultrasonic instrumentation produced effects on the root surface almost similar to that of hand instrumentation. Er:YAG laser and Er,Cr:YSGG laser clarify a little more surface roughness when compared with conventional instruments. Conclusions: The present systematic review indicates that a combination of scaling and root planing (SRP) using the erbium lasers as an adjunctive therapy at certain parameters can be appropriate to remove residual debris from the root surface and at the same time have little or no negative thermal effect on the root surface. The Er:YAG laser also seems to be the most suitable for nonsurgical periodontal therapy. Additional new good-designed studies are needed to evaluate the effectiveness of erbium lasers with SRP in nonsurgical periodontal therapy.

Dual micelles-loaded gelatin nanofibers and their application in lipopolysaccharide-induced periodontal disease

INTRODUCTION

Combined therapies utilizing inhibitors to remove pathogens are needed to suppress lipopolysaccharide (LPS)-induced periodontal disease. We prepared a novel, multi-agent delivery scaffold for periodontal treatment.

METHODS

In this study, we synthesized SP600125 (a JNK inhibitor) and SB203580 (a p38 inhibitor) drug-loaded poly(ethylene glycol)-block-caprolactone copolymer via dialysis method. The physical property of micelles was characterized through dynamic light scattering and transmission electron microscopy. The cell growth and LPS-induced MMP-2 and MMP-13 expression were evaluated through CCK-8, real-time PCR and Western blot assay. The release of SP600125 and SB203580 from different scaffolds was estimated. Microcomputed tomography and histology were used for evaluating the effect of the micelles-loaded nanofibers on the treatment of class II furcation defects in dogs.

RESULTS

The drug was then successfully incorporated into gelatin fibers during electrospinning process. We confirmed that the micelles had spherical structure and an average particle size of 160 nm for SP600125-micelles (SP-Ms) and 150 nm for SB203580-micelles (SB-Ms). The nanofiber scaffold showed excellent encapsulation capability, in vitro drug-release behavior, and cell compatibility. Real-time PCR and Western blot assay further indicated that LPS-induced MMP-2 and MMP-13 expression was significantly inhibited by the scaffold.

CONCLUSION

The results suggested that the dual drug-loaded system developed in this study might become a highly effective therapy for periodontal disease.

Substrate roughness induces the development of defective E-cadherin junctions in human gingival keratinocytes

Purpose

The entry of bacteria or harmful substances through the epithelial seal of human gingival keratinocytes (HGKs) in the junctional epithelium (JE) is blocked by specialized intercellular junctions such as E-cadherin junctions (ECJs). However, the influence of roughened substrates, which may occur due to apical migration of the JE, root planing, or peri-implantitis, on the development of the ECJs of HGKs remains largely unknown.

Methods

HGKs were cultured on substrates with varying levels of roughness, which were prepared by rubbing hydrophobic polystyrene dishes with silicon carbide papers. The activity of c-Jun N-terminal kinase (JNK) was inhibited with SP600125 or by transfection with JNK short hairpin RNA. The development of intercellular junctions was analyzed using scanning electron microscopy or confocal laser scanning microscopy after immunohistochemical staining of the cells for E-cadherin. The expression level of phospho-JNK was assessed by immunoblotting.

Results

HGKs developed tight intercellular junctions devoid of wide intercellular gaps on smooth substrates and on rough substrates with low-nanometer dimensions (average roughness [Ra]=121.3±13.4 nm), although the ECJs of HGKs on rough substrates with low-nanometer dimensions developed later than those of HGKs on smooth substrates. In contrast, HGKs developed short intercellular junctions with wide intercellular gaps on rough substrates with mid- or high-nanometer dimensions (Ra=505.3±115.3 nm, 867.0±168.6 nm). Notably, the stability of the ECJs was low on the rough substrates, as demonstrated by the rapid destruction of the cell junction following calcium depletion. Inhibition of JNK activity promoted ECJ development in HGKs. JNK was closely associated with cortical actin in the regulation of ECJs in HGKs.

Conclusions

These results indicate that on rough substrates with nanometer dimensions, the ECJs of HGKs develop slowly or defectively, and that this effect can be reversed by inhibiting JNK.

Effects of Root Debridement With Hand Curettes and Er:YAG Laser on Chemical Properties and Ultrastructure of Periodontally-Diseased Root Surfaces Using Spectroscopy and Scanning Electron Microscopy

Introduction: The efficacy of erbium-doped yttrium aluminum garnet (Er:YAG) laser for root debridement in comparison with curettes has been the subject of many recent investigations. Considering the possibility of chemical and ultra-structural changes in root surfaces following laser irradiation, this study sought to assess the effects of scaling and root planing (SRP) with curettes and Er:YAG laser on chemical properties and ultrastructure of root surfaces using spectroscopy and scanning electron microscopy (SEM). Methods: In this in vitro experimental study, extracted sound human single-rooted teeth (n = 50) were randomly scaled using manual curettes alone or in conjunction with Er:YAG laser at 100 and 150 mJ/pulse output energies. The weight percentages of carbon, oxygen, phosphorous and calcium remaining on the root surfaces were calculated using spectroscopy and the surface morphology of specimens was assessed under SEM. Data were analyzed using one-way analysis of variance (ANOVA). Results: No significant differences (P > 0.05) were noted in the mean carbon, oxygen, phosphorous and calcium weight percentages on root surfaces following SRP using manual curettes with and without laser irradiation at both output energies. Laser irradiation after SRP with curettes yielded rougher surfaces compared to the use of curettes alone. Conclusion: Although laser irradiation yielded rougher surfaces, root surfaces were not significantly different in terms of chemical composition following SRP using manual curettes with and without Er:YAG laser irradiation. Er:YAG laser can be safely used as an adjunct to curettes for SRP.

Scaling and root planning, and locally delivered minocycline reduces the load of Prevotella intermedia in an interdependent pattern, correlating with symptomatic improvements of chronic periodontitis: a short-term randomized clinical trial

Background

To evaluate the respective or combinatory efficacy of locally delivered 2% minocycline (MO), and scaling and root planning (SRP) by assessing both clinical parameters and the loads of four main periodontal pathogens in treating chronic periodontitis (CP).

Methods

Seventy adults with CP were randomly assigned to the three treatment groups: 1) SRP alone; 2) MO alone; and 3) combinatory use of SRP and MO (SRP + MO). Before and 7 days after the treatments, we evaluated both clinical parameters (pocket depth [PD] and sulcus bleeding index [SBI]) and the gene load of four main periodontal pathogens (Aggregatibacter actinomycetemcomitans [Aa], Fusobacterium nucleatum [Fn], Porphyromonas gingivalis [Pg], and Prevotella intermedia [Pi]).

Results

The bacterial prevalence per patient was: Aa, 31.25%; Fn, 100%; Pg, 95.31%; and Pi, 98.44%. Seven days after treatment, the three treatments significantly reduced both PD and SBI, but not detection frequencies of the four pathogens. For PD, the reduction efficacy of SRP + MO was significantly higher than that of either MO or SRP. Only Pg responded significantly to SRP. Pg and Fn were significantly reduced in the presence of MO. Only SRP + MO showed a significant reduction effect on the gene load of Pi. The reduction of PD significantly correlated with the gene load of Pi (r=0.26; P=0.042) but not of the other bacteria.

Conclusion

SRP and MO reduced the load of Pi in an interdependent pattern, which correlated with symptomatic improvements of CP.

Evaluation of the effect of low level laser therapy toothbrush in treatment of dentin hypersensitivity

INTRODUCTION

Dentin hypersensitivity is one of the most common complications that affect patients after periodontal therapy. Recently low level laser therapy has been introduced as a new treatment modality and has produced beneficial results. The purpose of this study is to evaluate the effect of low level laser therapy toothbrushes in reduction of dentin hypersensitivity.

METHODS

In this pilot interventional controlled clinical trial, 40 patients suffering from dentin hypersensitivity were selected using simple randomization. Half of the patients were given laser toothbrushes and the other half was given non-laser sensodyne toothbrushes. Primary dentin hypersensitivity was recorded by visual analogue scale (VAS) score and ice spray. Then dentin hypersensitivity was measured right after the treatment as well az in the intervals of 1 month and 2 months after initiation of the study. Data were compared using Statistical Package for the Social Sciences (SPSS) software and Analysis of variance (ANOVA) paired T test.

RESULTS

The results of this study showed that there was a significant difference in each of the two kinds of tooth brushes separately for all time intervals (P < 0.001). Also the effect of the type of toothbrush was investigated using before treatment VAS with covariance analyses. P values for immediately, 1 month and 2 months after treatment were calculated to be 0.078, 0.02, 0.01 respectfully. Also the effect of the toothbrush type was significant in the manner that laser toothbrushes reduce dentin hypersensitivity more than ordinary toothbrushes (P< 0.05).

CONCLUSION

Both sensodyne and laser tooth brushes improve dentin hypersensitivity, although the laser toothbrush led to better results in short.