Simultaneous 3D reconstruction and implant placement using allogenic laminar bone membranes in atrophic Mandible. A comparative clinical study

Objective: to compare the outcome of allogenic bone sheets clinically and radiographically in posterior mandibular vertical augmentation in Luhr class III cases with simultaneous implant placement using autogenous versus xenografts. Patients and methods: this study was based on a total of 12 implants placed in 4 patients, 2 of which were males and 2 females. Patients were divided into 2 groups, both treated with implants placed with exposed threads 3 mm crestally and covered buccolingually with the laminar bone membrane; group 1 received autogenous bone obtained from the same surgical site using 4.5 diameter ACM bur mixed with PRP and packed around the crestally exposed implant threads. Group 2 received xenograft bone particles mixed with PRP and packed around the crestally exposed implant threads in the same manner. Results: CBCT was done pre-operatively, immediate post-operatively and 4 months post-operatively for each implant to compare the bone gain radiographically. In group 1, the mean amount of residual bone height pre-operatively was 7.8 mm (SD 0.86) and increased to 14.44 mm (SD 1.75) and 14.1 mm (SD 1.85) immediate and 4 months post-operatively, respectively. The mean amount of bone gain after 4 months was 6.3 mm, denoting a minimal amount of graft loss during the first 4 postoperative months was 0.27 mm (less than 2%). In group 2, the mean amount of residual bone height pre-operatively was 8.37 mm (SD 0.99) and increased to 12.86 mm (SD 1.75) and 12.53 mm (SD 1.65) immediate and 4 months post-operatively, respectively. The mean amount of bone gain after 4 months was 4.16 mm, denoting a minimal amount of graft loss during the first 4 postoperative months was 0.33 mm (less than 3%). Upon comparing bone gain in both groups, Group I (Autogenous) had a bone gain of 6.33 mm versus 4.16 mm for Group II (Xenograft). Denoting more gain in Group I (autogenous). While the amount of graft loss between the immediate and 4 months postoperative CBCT was less than 2% and less than 3% in the autogenous versus the xenograft group respectively . Conclusion: Cases initially lacking keratinized mucosa will need soft tissue intervention along with this technique. Exposure after 4 months appeared to have been too early, which lead to bone loss and exposed threads. Bilateral augmentation has led to patients using the grafted edentulous sites for mastication early following soft tissue healing, prior to prosthetics, which might suggest that tooth-bounded posterior edentulous sites might be a better candidate for such technique. Results were clinically different than radiographically in the CBCT, so longer lag time is recommended before loading. Keywords: mandibular atrophy, bone graft, implants, laminar bone sheet

Effect of low-level diode laser bio-stimulation on implant stability before, during and after immediate implants in mandibular molars. (A randomized clinical study)

Introduction: Tooth loss can affect the person’s life dramatically. Tooth loss is accompanied by bone loss in all dimensions, so preservation of the bone is mandatory for placement of dental implant. Immediate implant can preserve alveolar bone. Due to difference in shape between the implants and extracted roots a gap appears between the immediately placed implant and the extraction socket resulting in jumping distance, Bone grafts are commonly used to fill this gap, recent studies suggest that jumping gaps shouldn’t always be grafted. Low level bio stimulation has stimulatory effect on bone cells so it can be used in immediate implants to increase bone formation around the implants. Patients and methods: this study was carried in the hospital of future university. A total of twelve patients with non-restorable mandibular molar participated in this study. A total of twenty implants were placed immediately in mandibular molar region without bone grafting, thew were divided equally into two groups. Surgical technique was similar for both groups. After immediate implant placement with primary stability of 35 N, both groups received custom made healing collar using flowable composite to seal the jumping distance. The study group (intervention) received a total of 60J/cm2 .10J/cm2 3 days before extraction, another 10J/cm2 at the fresh socket, another 10 J/cm2 after osteotomy, another 10J/cm2 after implant placement, another 20J/cm2 at the follow up visit with 3 days interval. After six weeks secondary implant stability was measured for both groups using Resonance Frequency Analysis device (RFA). Prosthetic phases started for implants that showed sufficient secondary stability. Results: All implants enrolled in this study showed sufficient secondary stability except for one totally avulsed implant from the control group. Study group showed more stability upon measuring using Resonance frequency analysis device after six weeks of implant placement. The study group has shown a higher secondary stability compared to control group, the mean implant stability quotient value of study (71.89±2.67) was significantly higher than control (62.43±8.62). Conclusion: Based on the results of our study we concluded that low level diode laser 980nm has a stimulatory effect on bone formation when applied before, during and after immediate implant placement, According to this study 60J/cm2 is recommended dose and it also gave better soft tissue healing result

Computer Guided Versus Conventional Maxillary Sinus Augmentation Using Allogenic Bone Blocks with Simultaneous Implant Placement in Severely Pneumatized Sinuses

Background: Maxillary sinus lifting is a complex procedure with reported complications in the literature where the presence of sinus septa further complicates the procedure, they including membrane perforation, bleeding. Aim: The aim of this study is to decrease the incidence of membrane perforation which is the most common reported complication, and to determine whether the use of surgical guides could decrease the incidence of membrane perforation. Materials and methods: A total of 12 cases where blindly divided into 2 groups; Group (A) computer guided maxillary sinus lifting and Group (B) conventional sinus lifting, both groups received allogenic bone blocks for sinus augmentation with simultaneous implant placement. Cone beam CT was performed pre operatively for planning the number and position of implants to be placed and for fabrication of the surgical guide. Results: In all cases the Schneiderian membrane was successfully elevated except for one case in Group (A) where membrane perforation occurred and 2 cases in Group (B) Conclusion: The use of surgical guide in sinus lifting procedures decreases the incidence of membrane perforation working time and improve implant positioning. Keywords: surgical guide, maxillary sinus lifting, allogenic bone blocks, simultaneous implant

Open sinus lift surgery and augmentation with (SCPC versus H.A): A systematic review

open sinus lift is used to augment the maxillary sinus prior to implant Placement in patients with sinus pneumatization due to early extraction of upper molars Where the remaining available bone length is from zero to 6mm which will not accommodate for implant placement and not sufficient for implant initial stability so we will need to do Sinus lift and augmentation of the sinus with various bone grafts either (alloplast, allograft, Autogenous). Search is conducted electronically on line in pub med & Cochrane and manual Search was also done from 2007 to 2018 the articles included assisting &evaluating various types of bone substitute used in open sinus lift surgeries.197 papers are identified through data base searching 37 Additional records identified through manual search, after duplication removal the remaining papers are 187,187 paper were reviewed&152 were excluded by title &abstract, 35 article were reviewed as full text, 27 articles were excluded by reason, 8 articles were included in this study, Eight included articles have revealed new bone formation with percentage ranges from 48%as the highest percentage&16.4 as the lowest percentage, residual material ranges from 6.3%to 34.8% which differs according to type of bone graft used, histological evaluation is performed in 7 articles in addition to radiological evaluation only one article used radiographic evaluation only This systematic review supported the fact that bone substitute act as a scaffold for new bone formation with different percentages according to type of bone substitute used

Three-Dimensional Maxillary Alveolar Ridge Augmentation Using Modified Cortical Shell Technique and Composite Bone Graft

Objective: The present study was performed to assess the 3D alveolar ridge augmentation using the cortical shell from retromolar region and composite bone particulate regarding the width of the residual alveolar ridge. Methods: Thirteen patients with age range 21-40 years old having atrophic anterior maxillary ridge ≤3mm horizontally were included in the study. All patients were subjected to ridge augmentation using composite bone graft and retromolar cortical shell that was fixed in place by two micro-screws. The alveolar ridges were assessed and compared by cone beam computed tomography (CBCT) in the pre-operative, immediate and 4 months post-operative phases by taking linear measurements at the same points after making fusion. The measurements were taken at the crest of the ridge, midway and more apically. The CBCT images were evaluated for the actual gain in width of the alveolar ridge. Statistical analysis was performed to compare CBCT and clinical findings. Results: At the crest of the ridge, midway and more apically the results showed a statistically significant difference between pre-operative and immediate post-operative results (P0.05). The mean increases in crestal bone width, midway and apically at 4 months postoperatively were 3.66mm, 4.01mm and 3.5mm respectively. Conclusion: 3D reconstruction of anterior maxillae with autogenous retromolar cortical shell is a reliable technique with stable outcomes. Two micro-screws Stabilization provides stability and minimal graft resorption. Moreover, the technique allows for implant placement 4 months post-operatively without further re-grafting

Vascularised versus Non Vascularised Autogenous Bone Grafts for Immediate Reconstruction of Segmental Mandibular Defects: A Systematic Review

Introduction: This systematic review was performed to address the focus question " what is the various success rates and complications of both vascularised and non vascularised bone grafts for immediate segmental mandibular reconstruction" in addition, this paper reviews various forms, recent advances and possible complications of autogenously vascularised and non vascularised bone grafts for mandibular reconstruction that were previously discussed in the literature. Methodology: A thorough Medline database search performed on related terms yielded 389 titles. 202 studies were excluded after title screening. Out of 187 abstracts selected, 180 full text articles were obtained for further evaluation. Results showed that a total of 51 studies followed the inclusion criteria included in this systematic review. A primary analysis of the included studies showed that the majority were case series studies (37 articles) and only 5 Randomized controlled trials and 12 case reports were identified with most not providing objective outcomes of their results. Therefore quantitative data analysis and subsequent meta-analysis could not be performed. Results showed variable success rates and complications of different immediate autogenously graft forms. Conclusion: both vascularised & non vascularised bone grafts could be used with different range of satisfactory results depending on many factors such as the size and site of the defect, patient age, histopathology of the lesion, fixation methods and radiotherapy

Up-regulation of the G3PDH ʻhousekeeping’ gene by estrogen

Proteomic and genomic studies commonly involve the assessment of mrna levels using reverse transcription- polymerase chain reaction (Pcr) and real-time quantitative Pcr. an internal standard rna is fundamentally analyzed along with the investigated mRNA to document the specificity of the effect(s) on mrna and to correct for inter-sample variations. in our studies implementing estrogen treatments on different cell lines, we initially used glyceraldehyde-3- phosphate dehydrogenase (G3PdH) as an internal standard. However, the results of PCR amplification demonstrated that 17β-estradiol enhanced the expression of the G3PdH gene, rendering it impossible to use G3PdH as an unbiased com- parative control

Effect of estrogen on bone resorption and inflammation in the temporomandibular joint cellular elements

Several epidemiological studies have reported that temporomandibular disorder is more prevalent in women, which suggests the involvement of sex hormones, such as estrogen, in the pathogenesis of this disease. PCR amplification and Western blotting were employed to target the expression of estrogen receptors (ERs) in human fibroblast-like synovial and ATDC5 cells. The effect of estrogen was investigated through the expression of RANKL, osteoprotegerin (OPG), M-CSF/CSF-1 and c-fms. We showed expression of M-CSF/ CSF-1 and c-fms, with time-dependent increase in both after the addition of estrogen. Based on previous studies reporting that M-CSF/CSF-1 regulates the proliferation and differen- tiation of hemopoietic progenitor cells into mature macro- phages, we put forward a new hypothesis based on the increased inflammation and tendency of females to suffer more from temporomandibular disorder (TMD) in the presence of external exacerbating factors. Detection of RANKL and OPG in ATDC5 and expression of both in HFLS was confirmed with complete disappearance of the RANKL band, and marked increase in the expression of OPG after 1 h from the addition of estrogen

Regulation of Human and Pig Renal Na+,K+-ATPase Activity by Tyrosine Phosphorylation of Their a1-Subunits

Abstract Modulation of the physiologically influential Na?,K?-ATPase is a complex process involving a wide variety of factors. To determine the possible effects of the protein tyrosine phosphatase (PTP) inhibitors dephostatin and Et-3,4-dephostatin on human and pig, renal cells and enzymatic extracts, we treated our samples (15 min–24 h) with those PTP inhibitors (0–100 lM). PTP inhibitors were found to possess a concentration-dependent inhibition of Na,K-ATPase activity in both human and pig samples.The inhibition was similarly demonstrated on all cellular, microsomal fraction and purified Na,K-ATPase levels.Despite rigorous activity recovery attempts, the PTP inhibitors’ effects were sustained on Na?,K?-ATPase activity. Western blotting experiments revealed the expression of both a1- and b1-subunits in both human and pig tissues. a1-Subunits possessed higher tyrosine phos- phorylation levels with higher concentrations of PTP inhibitors. Meanwhile, serine/threonine residues of both a1- and b1-subunits demonstrated diminished phosphorylation levels upon dephostatin treatment. Accordingly, we pro-vide evidence that Na?,K?-ATPase can be regulated through tyrosine phosphorylation of primarily their subunits, using PTP inhibitors