Volumetric evaluation of effects of platelet-rich fibrin and concentrated growth factor on early bone healing after endodontic microsurgery: a randomized controlled trial.

BACKGROUND: This randomized controlled clinical trial compared the effects of platelet-rich fibrin (PRF) and concentrated growth factor (CGF) on early bone healing after endodontic microsurgery. METHODS: Eighteen patients with an isolated periapical lesion < 10 mm in the maxillary anterior region were randomly assigned to three groups: control, PRF, or CGF. Endodontic microsurgery was performed and PRF or CGF membranes were placed over the bone defects in the experimental groups. The volume of the bone defect at postoperative one week, three months, and six months was evaluated using cone-beam computed tomography and Mimics software. The results were statistically analyzed using the Kruskal-Wallis test and post-hoc Mann-Whitney U test with Bonferroni correction. RESULTS: At the three-month follow-up, the PRF and CGF groups showed significantly greater bone healing compared with the control group (p > 0.05). However, no significant difference was observed between the PRF and CGF groups. At the six-month follow-up, no significant differences were observed between the groups. CONCLUSIONS: These results suggested that PRF and CGF promote early bone healing after endodontic microsurgery.

Technical Note on Vestibuloplasty around Dental Implants Using Erbium YAG Laser-Assisted Periosteal Fenestration (LA-PF).

Various vestibuloplasty techniques have been reported to increase the attached mucosa (AM) and vestibular depth around dental implants. However, these surgical methods have disadvantages, such as limitations in manipulation, necessity of suturing, postoperative discomfort, swelling, and pain. This study aimed to evaluate the efficacy of laser-assisted periosteal fenestration (LA-PF) in treating patients with a shallow vestibule and insufficient AM around dental implants. LA-PF was performed using an Erbium YAG laser (Er:YAG laser). First, a partial-thickness, apically positioned flap was used. A horizontal periosteal fenestration was performed using an Er:YAG laser to expose the bones. Periosteal suturing was not required. After 12 months, sufficient AM and deep vestibules were obtained and maintained. Thus, the LA-PF technique may be a simple and predictable treatment modality for shallow vestibules with insufficient AM around dental implants.

Technical Note on Simplified Free Gingival Graft Using Tack Fixation (sFGG).

Free gingival graft (FGG) is the gold standard procedure for the reliable augmentation of lost keratinized mucosa (KM) around dental implants. This conventional surgical approach has its drawbacks, including limitations in manipulation, the requirement for suturing, postoperative discomfort, and pain. This case report aimed to evaluate the efficacy of a simplified free gingival graft (sFGG) in addressing the issue of inadequate keratinized mucosa around dental implants. Fixation tacks were used to perform the sFGG procedure. Initially, a partial-thickness flap was created and apically repositioned. The gingival graft was harvested from the palate with a narrow profile and securely affixed to the recipient site using 5 mm long fixation tacks. Significant gains in keratinized mucosa were achieved and successfully maintained within 1 year. Consequently, the sFGG technique emerges as a simple and reliable treatment approach for managing inadequate keratinized mucosa around dental implants.

Implant Placement after Closure of Oroantral Communication by Sinus Bone Graft Using a Collagen Barrier Membrane in the Shape of a Pouch: A Case Report and Review of the Literature.

Oro-antral communication (OAC) acts as a pathway for bacteria between the maxillary sinus and oral cavity, and is a common complication after the removal of a dental implant or extraction of a tooth from the maxillary posterior area. In the case of an untreated OAC, oro-antral fistula develops and becomes epithelialized. We aimed to introduce a treatment for OAC closure via a sinus bone grafting procedure using bone tacks and a collagen membrane with an allograft. The procedure was performed by applying an absorbable membrane made in pouch form. This membrane acted as a barrier for closing the large sinus membrane perforation. Bone tacks were used to fix the membranes. Subsequently, the maxillary sinus was filled with the allograft, and the absorbable membrane was reapplied. Primary closure was achieved by performing a periosteum-releasing incision for a tension-free suture. After 6 months, sufficient bone dimensions were gained without any occurrence of maxillary sinusitis or recurrence of OAC. Additional bone grafts and implantation could be performed to rehabilitate the maxillary posterior area. We conclude that this technique might be a useful treatment for reconstructing the maxillary posterior area with simultaneous sinus bone graft and OAC closure.

Fusobacterium pseudoperiodonticum sp. nov., Isolated from the Human Oral Cavity.

In the present study, three strains (ChDC F213T, ChDC F251, and ChDC F267) were classified as novel species of genus Fusobacterium based on average nucleotide identity (ANI) and genome-to-genome distance (GGD) analysis and chemotaxonomic characterization. 16S rDNA sequences of strains ChDC F213T, ChDC F251, and ChDC F267 were highly similar to that of F. periodonticum ATCC 33693T (99.6, 99.4, and 99.4%, respectively). ANI and GGD values of the three isolates with F. periodonticum ATCC 33693T ranged from 92.5 to 92.6% and 47.7 to 48.2%, respectively. Considering that threshold of ANI and GGD values for bacterial species discrimination are 95-96% and 70%, respectively, these results indicate that the three isolates represent a novel Fusobacterium species. DNA G + C contents of the three isolates were 28.0 mol% each. Cellular fatty acid analysis of these strains revealed that C14:0, C16:0, and C16:1 ω6c/C16:1 ω7c were major fatty acids. Therefore, these three strains are novel species belonging to genus Fusobacterium. Strain ChDC F213T (= KCOM 1259T = KCTC 5677T = JCM 33009T) is the type strain of a novel species of genus Fusobacterium, for which a name of Fusobacterium pseudoperiodonticum sp. nov. is proposed.

Lautropia dentalis sp. nov., Isolated from Human Dental Plaque of a Gingivitis Lesion.

A novel Gram-stain-negative, motile, and facultative anaerobic coccus, strain ChDC F240T was isolated from human subgingival dental plaque of a gingivitis lesion. The phylogenetic analysis based on the 16S ribosomal RNA gene (16S rDNA) sequence showed that the strain belonged to the genus Lautropia. 16S rDNA of strain ChDC F240T had the highest similarity to that of Lautropia mirabilis ATCC 51599T (98.8%). Major cellular fatty acids of strain ChDC F240T were C16:0 (43.9%) and C16:1ω6C/C16:1ω7C (38.1%). Draft genome of the strain was 3,834,139 bp in length and the G+C content was 65.0 mol%. Average nucleotide identity and genome-to-genome distance values between strain ChDC F240T and L. mirabilis ATCC 51599 T were 81.99% and 28.50% (26.1-30.9%), respectively. These results reveal that strain ChDC F240T is a novel species within the genus Lautropia, for which the name Lautropia dentalis sp. nov. is proposed; type strain is ChDC F240T (= KCOM 2505T = JCM 33297T).

Six Month Clinical Evaluation of Interdental Papilla Reconstruction with Injectable Hyaluronic Acid Gel Using an Image Analysis System.

PURPOSE: Obtaining predictable and aesthetically pleasing interdental papilla is challenging in dental reconstruction. Hyaluronic acid gel has been successfully used to reduce facial creases and similar abnormalities. The purpose of this study was to clinically assess the efficiency of interdental papilla reconstruction with injectable hyaluronic acid gel. MATERIALS AND METHODS: Ten patients with 43 treated sites in the maxillary anterior region were studied. Photographic standardization devices were designed for image analysis before treatment. This treatment was repeated up to five times during 3-week intervals. Patients were followed 6 months after initial gel application. RESULTS: Twenty-nine sites had complete papilla reconstruction and 14 sites improved from 39 to 96% of interdental papilla reconstruction rate. Complete interdental papilla reconstruction was performed when black triangle at initial examination had area of ≤0.25 mm(2) , height of ≤1mm, or width of ≤0.5mm. CONCLUSION: Injectable hyaluronic acid gel may be a promising treatment for enhancing papillary esthetics. CLINICAL SIGNIFICANCE: Interdental papilla reconstruction with injectable hyaluronic acid gel can be suggested as a minimally invasive treatment option for interdental papilla deficiencies in small areas. However, long-term results of this treatment beyond 6 months are not yet known. (J Esthet Restor Dent 28:221-230, 2016).

Sinus floor augmentation using mineralized freeze-dried bone allograft combined with recombinant human bone morphogenetic protein-2 (rhBMP-2): A long-term retrospective study.

Background/purpose: The combination of recombinant human bone morphogenetic protein-2 (rhBMP-2) with a carrier material has not been extensively studied. This study aimed to evaluate the clinical, radiological, and histomorphometric outcomes of sinus floor augmentation using a 3:7 mixture of cancellous and cortical freeze-dried bone allografts (mixed AG) combined with rhBMP-2. Materials and methods: Mixed AG was used for sinus floor augmentation in a total of 21 patients with a residual alveolar bone height <5 mm. Among the total 47 sites, augmentation with and without rhBMP-2 was performed in 26 and 21 sites, respectively. Radiographic parameters were assessed using cone-beam computed tomography. After a six-month healing period, core biopsies were harvested for histomorphometric analysis. Results: The bone gain after healing was 13.36 ± 3.9 mm and 12.07 ± 3.8 mm in the mixed AG alone and mixed AG with rhBMP-2 groups, respectively. The survival rate of implants in both groups was 100% during the follow-up period. The proportion of newly formed bone was 24.6 ± 10.2% and 39.7 ± 18.3% in the mixed AG alone and mixed AG with rhBMP-2 groups, respectively (P < 0.05). Moreover, the percentage of residual graft material was 21.0 ± 12.2% and 9.6 ± 10.0% in the mixed AG alone and mixed AG with rhBMP-2 groups, respectively (P < 0.05). Conclusion: Mixed AG combined with rhBMP-2 could be a suitable material for sinus floor augmentation. This combination may reduce the treatment time and improve the predictability of implant placement.

Radiographic and Histomorphometric Evaluation of Sinus Floor Augmentation Using Biomimetic Octacalcium Phosphate Alloplasts: A Prospective Pilot Study.

This prospective single-arm clinical study aimed to radiographically and histomorphometrically evaluate the efficacy of the lateral approach for sinus floor elevation (LSFE) using biomimetic octacalcium phosphate (OCP) synthetic bone graft (Bontree®). LSFE using Bontree® was performed on 10 patients (15 implant placement sites) willing to undergo implant surgery, followed by implant placements after 6 months of the healing period. The vertical bone height (VBH) and Hounsfield unit (HU) values at each implant placement site were evaluated radiographically using cone-beam computed tomography at baseline immediately after surgery (T1) and 6 months after surgery (T2). A histomorphometric evaluation of the bone core biopsy specimen was also performed. The mean VBH and HU changes at all sites included a decrease by 0.91 mm and a statistically significant increase by 431.86, respectively, from T1 to T2. The mean ratio of the newly formed bone (23.34% ± 10.63%) was greater than that of the residual bone graft (19.09% ± 8.74%), indicating that Bontree® is effective for new bone formation. This pilot study suggests that Bontree® is a promising bone substitute for LSFE.

A retrospective comparison of 3 approaches of vestibuloplasty around mandibular molar implants: apically positioned flap versus free gingival graft versus modified periosteal fenestration.

PURPOSE: This study aimed to clinically evaluate the efficacy of vestibuloplasty around lower molar implants using 3 different modalities: apically positioned flap alone (APF), APF with a free gingival graft (FGG), and APF with modified periosteal fenestration (mPF). METHODS: Three different vestibuloplasty procedures during second-stage implant surgery were performed at the mandibular molar area in 61 patients with a shallow vestibule and insufficient keratinized tissue (KT). The clinical measurements of KT width were recorded at baseline, immediately after surgery (T0), 6 months after surgery (T6), and 12 months after surgery (T12). Soft tissue esthetic scores were measured. RESULTS: An additional KT width gain from baseline to T12 of approximately 2 mm was obtained with FGG and mPF compared to that with APF. Shrinkage of the re-established tissue was lower with mPF and FGG than with APF, whereas the esthetic profile was better with APF and mPF than with FGG. CONCLUSIONS: Within the limitations of this study, mPF showed potential as a promising approach for vestibuloplasty around the lower molar implants compared to the traditional APF and FGG.

Hard Tissue Volume Stability Effect beyond the Bony Envelope of a Three-Dimensional Preformed Titanium Mesh with Two Different Collagen Barrier Membranes on Peri-Implant Dehiscence Defects in the Anterior Maxilla: A Randomized Clinical Trial.

This single-blinded, randomized, controlled study aimed to clinically and radiographically evaluate hard tissue volume stability beyond the bony envelope using three-dimensional preformed titanium mesh (3D-PFTM) for peri-implant dehiscence defects in the anterior maxilla. A total of 28 patients who wished to undergo implant surgery combined with guided bone regeneration (GBR) after extraction of a single maxillary anterior tooth were randomly assigned to two groups depending on the type of collagen membrane used, additionally with the 3D-PFTM-test (n = 14, cross-linked collagen membrane; CCM) and control (n = 14, non-cross-linked collagen membrane; NCCM) groups. Each implant was evaluated radiographically using CBCT at baseline, immediately after surgery, and at 6 months postoperatively. The relative position and distances from the bony envelope to the outlines of the augmented ridge were further determined immediately after GBR and 6 months after healing. At the platform level, the mean horizontal hard tissue gain (HG) at all the sites was 2.35 ± 0.68 mm at 6 months postoperatively. The mean HG rate was 84.25% ± 14.19% in the CCM group and 82.56% ± 13.04% in the NCCM group, but the difference was not significant between the groups. In all cases, HG was maintained beyond the bony envelope even after 6 months of GBR. This study suggests that 3D-PFTM should be considered a valuable option for GBR for peri-implant dehiscence defects in the anterior maxilla. In addition, 3D-PFTM may confer predictable hard tissue volume stability even after the healing period of hard tissue augmented outside the bony envelope by GBR.

Technical Note on Root Coverage of Lower Anterior Teeth Using a Partially Deepithelialized Connective Tissue Graft (PE-CTG) Aided by a High-Speed Handpiece.

Root coverage in the mandibular anterior region is challenging because of a thin gingival biotype, shallow vestibule, and high frenum attachment. Several methods have been introduced to predict the root coverage in this area. Stimmelmayr proposed a method of performing root coverage using a combination epithelialized-subepithelial connective tissue graft (CTG). However, it is difficult to precisely acquire connective tissue according to this method. Therefore, in this case report, we would like to introduce a technique to harvest a partially deepithelialized CTG (PE-CTG) aided by a high-speed handpiece, which helps in procuring the graft easily and quickly. This method could lower the patient's morbidity at donor sites and enhance the healing process. Additionally, it could increase the amount of keratinized gingiva in the mandibular anterior region without reducing the vestibular depth. Therefore, PE-CTG using a high-speed handpiece can be a promising treatment option for the root coverage of the mandibular anterior teeth.

Sinus floor augmentation using mixture of mineralized cortical bone and cancellous bone allografts: Radiographic and histomorphometric evaluation.

BACKGROUND/PURPOSE: Due to the pneumatization of the maxillary sinus, the sinus floor augmentation is often performed to implant placement in the maxillary posterior region. The aim was to perform radiographic and histomorphometric evaluation after placement of mixed allografts (cortical freeze-dried bone allograft [FDBA] 50%:cancellous FDBA 50%) during sinus floor augmentation. MATERIALS AND METHODS: In 37 patients, anorganic bovine bone (ABB, sites = 16), mineralized cancellous bone allograft (MCBA, sites = 15), and mixed allografts (Mixed AG, sites = 20) were placed during sinus floor elevation via the lateral approach (LSFE), at total 51 sites with residual alveolar bone height (RBH) < 5 mm. Cone-beam computed tomography images were obtained before LSFE (T0), after surgery (T1), and 6 months after surgery (T2) for radiographic analysis. After a 6-month healing period, core biopsies were harvested and histomorphometric analysis was performed. RESULTS: The mean augmented bone height (ABH) of ABB, MCBA, and mixed AG groups after surgery was similar (13.86 ±â€¯4.19 mm, 13.99 ±â€¯4.07 mm, and 14.20 ±â€¯3.12 mm, respectively; P > 0.05). The mean ABH of ABB, MCBA, and mixed AG groups after 6 months was similar (13.72 ±â€¯4.55 mm, 11.83 ±â€¯3.31 mm, and 12.53 ±â€¯2.97 mm, respectively; P > 0.05). In the ABB, MCBA, and mixed AG groups, the proportion of newly formed bone (NB) was similar (36.13 ±â€¯10.01%, 39.26 ±â€¯10.72%, and 31.27 ±â€¯18.31%, respectively; P > 0.05). CONCLUSION: This result demonstrated that mixed AG led to sufficient bone augmentation and histologically comparable NB formation as compared to ABB and MCBA for sinus floor augmentation.

Novel Use of Silicone Sheets for Immediate Implant Placement in Fresh Molar Extraction Sockets.

In the recent years, the immediate placement of dental implants into fresh extraction sites has become an acceptable treatment approach. However, immediate molar implant placement presents specific challenges because of the anatomical and physiologic limitations. Such implant surgeries commonly require procedures that use a barrier membrane to generate bone and soft tissue or one that seals the molar extraction socket through a coronally advanced flap. Here, as an alternative, we report a method for treating molar extraction socket wounds in the hard and soft tissues after immediate placement of an implant using a silicone sheet.

Effects of 1,25-dihydroxyvitamin D3 on the differentiation of MC3T3-E1 osteoblast-like cells.

PURPOSE: The purpose of this study was to evaluate the effects of 1,25-dihydroxyvitamin D3 on the proliferation, differentiation, and matrix mineralization of MC3T3-E1 osteoblast-like cells in vitro. METHODS: MC3T3-E1 osteoblastic cells and 1,25-dihydroxyvitamin D3 were prepared. Cytotoxic effects and osteogenic differentiation were evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, alkaline phosphatase (ALP) activity assay, ALP staining, alizarin red S staining, and reverse transcription-polymerase chain reaction (RT-PCR) for osteogenic differentiation markers such as ALP, collagen type I (Col-I), osteocalcin (OCN), vitamin D receptor (VDR), and glyceraldehyde 3-phosphate dehydrogenase. RESULTS: The MTT assay showed that 1,25-dihydroxyvitamin D3 did not inhibit cell growth and that the rate of cell proliferation was higher than in the positive control group at all concentrations. ALP activity was also higher than in the positive control group at low concentrations of 1,25-dihydroxyvitamin D3 (10-10, 10-12, and 10-14 M). RT-PCR showed that the gene expression levels of ALP, Col-I, OCN, and vitamin D receptor (VDR) were higher at a low concentration of 1,25-dihydroxyvitamin D3 (10-12 M). Alizarin red S staining after treatment with 1,25-dihydroxyvitamin D3 (10-12 M) showed no significant differences in the overall degree of calcification. In contrast to the positive control group, formation of bone nodules was induced in the early stages of cell differentiation. CONCLUSIONS: We suggest that 1,25-dihydroxyvitamin D3 positively affects cell differentiation and matrix mineralization. Therefore, it may function as a stimulating factor in osteoblastic bone formation and can be used as an additive in bone regeneration treatment.

Production of a fermented organic rice syrup with higher isomalto-oligosaccharide using Lactobacillus plantarum.

Isomalto-oligosaccharide (IMO) syrup was prepared from organic rice, in which Lactobacillus plantarum as a starter was inoculated to raise its purity and also produce a fermented rice beverage. Of the five strains of lactic acid bacteria tested, L. plantarum was preferentially selected in terms of a viable cells (7.3 × 108 colony forming unit (CFU/mL) and higher dry cell weight (13 mg/mL). The fermented syrup-based medium did not affect the growth of L. plantarum. As expected, the residual sugar content gradually decreased by 1.34% compared with the initial concentration. It was apparent that the residual sugars but not oligosaccharides were removed during the L. plantarum fermentation period. The production of lactic acid was the highest (8125.78 mg/kg) among the organic acids produced in the fermented IMO syrup.

The association between radiographic embrasure morphology and interdental papilla reconstruction using injectable hyaluronic acid gel.

PURPOSE: The purpose of this study was to evaluate the clinical efficacy of enhancing deficient interdental papilla with hyaluronic acid gel injection by assessing the radiographic anatomical factors affecting the reconstruction of the interdental papilla. METHODS: Fifty-seven treated sites from 13 patients (6 males and 7 females) were included. Patients had papillary deficiency in the upper anterior area. Prior to treatment, photographic and periapical radiographic standardization devices were designed for each patient. A 30-gauge needle was used with an injection-assistance device to inject a hyaluronic acid gel to the involved papilla. This treatment was repeated up to 5 times every 3 weeks. Patients were followed up for 6 months after the initial gel application. Clinical photographic measurements of the black triangle area (BTA), height (BTH), and width (BTW) and periapical radiographic measurements of the contact point and the bone crest (CP-BC) and the interproximal distance between roots (IDR) were undertaken using computer software. The interdental papilla reconstruction rate (IPRR) was calculated to determine the percentage change of BTA between the initial and final examination and the association between radiographic factors and the reconstruction of the interdental papilla by means of injectable hyaluronic acid gel were evaluated. RESULTS: All sites showed improvement between treatment examinations. Thirty-six sites had complete interdental papilla reconstruction and 21 sites showed improvement ranging from 19% to 96%. The CP-BC correlated with the IPRR. More specifically, when the CP-BC reached 6 mm, virtually complete interdental papilla reconstruction via injectable hyaluronic acid gel was achieved. CONCLUSIONS: These results suggest that the CP-BC is closely related to the efficacy of hyaluronic acid gel injection for interdental papilla reconstruction.

The magnetic properties and microstructure of Co-Pt thin films using wet etching process.

Perpendicular magnetic recording (PMR) is a promising candidate for high density magnetic recording and has already been applied to hard disk drive (HDD) systems. However, media noise still limits the recording density. To reduce the media noise and achieve a high signal-to-noise ratio (SNR) in hard disk media, the grains of the magnetic layer must be magnetically isolated from each other. This study examined whether sputter-deposited Co-Pt thin films can have adjacent grains that are physically isolated. To accomplish this, the effects of the sputtering conditions and wet etching process on magnetic properties and the microstructure of the films were investigated. The film structure was Co-Pt (30 nm)/Ru (30 nm)/NiFe (10 nm)/Ta (5 nm). The composition of the Co-Pt thin films was Co-30.7 at.% Pt. The Co-Pt thin films were deposited in Ar gas at 5, 10, 12.5, and 15 mTorr. Wet etching process was performed using 7% nitric acid solution at room temperature. These films had high out-of-plane coercivity of up to 7032 Oe, which is twice that of the as-deposited film. These results suggest that wet etched Co-Pt thin films have weaker exchange coupling and enhanced out-of-plane coercivity, which would reduce the medium noise.