Implant surgical guides are often fabricated using CBCT technology. In this study, an alternative technique is proposed. The aim of this in vitro study was to compare the accuracy of the guide sleeve ...corrections of a geometric approach to guided surgery to the accuracy of in vitro studies of stereolithographic guides.
Four arch forms were milled from acrylic blocks each with 12 root form sites. Root form inserts were made. Holes were milled in the inserts at arbitrary angles. Guide posts were placed in these sites. Guide sleeves were placed on the posts and connected with light-cured resin to form verification jigs. The goal was to correct the angles of the guide sleeves to a vertical position 90 degrees from the base of the arch forms. The initial angles from the vertical and horizontal positions of the center of each guide sleeve were determined radiographically and geometrically. Horizontal and angle corrections were made using two-piece guide posts. Guide sleeves placed over the corrected guide posts were connected with light-cured resin, forming new verification jigs. The accuracy of the angle correction and the coronal horizontal and apical horizontal deviations of the 3-mm guide sleeves were determined. The experimental sites were divided into two groups to determine if the size of the initial angles of the guide sleeves had any effect on the accuracy of the corrections.
The initial angles of the guide sleeves before corrections revealed the mean difference between the two methods of measurements in groups 1 and 2 as 0.36 degrees (P = .14) and 0.69 degrees (P = .07), respectively. A comparison of the angle error measurements from 90 degrees after corrections between the two groups in the mesiodistal and buccolingual planes was not significant. The coronal and apical horizontal deviations after corrections revealed a significant difference between the two groups at the coronal level (P = .005) but not at the apical level (P = .14). In comparison of the methods of the two measurements of the angle error from vertical after corrections, the mean difference was 1.23 degrees (P = .01) and 0.69 degrees (P = .02).
The in vitro accuracy of the guide sleeve corrections made with the geometric approach for implant guidance was compared to the results of the meta-analyses of in vitro studies of implant placement with stereolithographic guides. The mean errors were smaller and within the recommendations of the EAO Consensus Conference of 2012.
Extraction of the natural tooth may be a prelude to implant placement. This may be done using an immediate placement protocol or require a delayed approach depending on multiple factors that include ...residual infection related to the failed tooth being extracted, availability of bone to stabilize the implant at placement, or soft tissue issues. Socket preservation is recommended when the delayed approach is selected to create an osseous bed with adequate height and width that can accommodate the implant that is planned.
The systemic oral health connection: Biofilms Kurtzman, Gregori M; Horowitz, Robert A; Johnson, Richard ...
Medicine (Baltimore),
2022-Nov-18, 2022-11-18, 20221118, Volume:
101, Issue:
46
Journal Article
Peer reviewed
Open access
Frequently, periodontal health and it's associated oral biofilm has not been addressed in those patients who have systemic health issues, especially those who are not responding to medical treatment ...via their physician. Oral biofilm may be present in the periodontal sulcus in the absence of clinical disease of periodontal disease (bleeding on probing, gingival inflammation) and periodontal reaction is dependent on the patient's immune response to the associated bacterial and their byproducts. Increasing evidence has been emerging the past decade connecting oral biofilm with systemic conditions, either initiating them or complicating those medical conditions. The patient's health needs to be thought of as a whole-body system with connections that may originate in the oral cavity and have distant affects throughout the body. To maximize total health, a coordination in healthcare needs to be a symbiosis between the physician and dentist to eliminate the oral biofilm and aid in prevention of systemic disease or minimize those effects to improve the patient's overall health and quality of life. Various areas of systemic health have been associated with the bacteria and their byproducts in the oral biofilm. Those include cardiovascular disease, chronic kidney disease, diabetes, pulmonary disease, prostate cancer, colon cancer, pancreatic cancer, pre-term pregnancy, erectile dysfunction Alzheimer's disease and Rheumatoid arthritis. This article will discuss oral biofilm, its affects systemically and review the medical conditions associated with the oral systemic connection with an extensive review of the literature.
Patients may present with failing mandibular dentition either involving the entire arch, partial arch that currently has a partial denture to replace the prior missing teeth or wearing a full ...denture. Finances may limit restoration of the arch with an All-on-X concept and the patient's goals are a stable prosthesis that does not move whenconcept and the patient's goals are a stable prosthesis that does not move when eating or speaking is the patient's expressed goal. Overdentures can fulfil that goal and provide a stable restored arch at a lower treatment cost than treatment with a fixed hybrid prosthesis. Traditionally, when these type cases have been treated, the remaining dentition has been extracted, depending on availability of bone, implants are placed. Those typically were left to osseointegrate and loaded several months later with a delayed loading approach. This requires relining the denture and the patient having a loose, non-stable prosthesis during that healing phase. An alternative approach utilizes immediate activation of the implants with overdenture attachments thus, providing an immediate stable retentive full arch mandibular removable prosthesis (overdenture) by immediate activation of overdenture attachments (ie.Locators) aids the patient in their goals without delays in treatment. This article will present two case examples of mandibular arches with failing dentition related to caries and periodontal issues and their treatment with immediate implant placement and loading with Locator attachments. Long-term follow-up of 1-year 8-months in one case and 33-months in the other case demonstrate crestal bone stability with this immediate overdenture loading protocol.
Peri-implantitis is an inflammatory process initiating in the soft tissue and then progressing to the hard tissue surrounding dental implants leading to loss of osseous support and potential loss of ...the implant if not identified early in the process. This process initiates in the soft tissue, which become inflamed spreading to the underlying bone leading to decreases in bone density with subsequent crestal resorption and thread exposure. In the absence of treatment of the peri-implantitis, the bone loss at the osseous implant interface progresses with inflammatory mediated decrease in the bone density that moves apically, eventually leading to mobility of the implant and its failure. Low-magnitude high-frequency vibration (LMHFV) has been shown to improve bone density, stimulate osteoblastic activity, and arrest progression of peri-implantitis with improvement of the bone or graft around the affected implant with or without surgery as part of the treatment. Two cases are presented using LMHFV to augment treatment.
Frozen section telepathology interpretation experience has been largely limited to practices with locations significantly distant from one another with sporadic need for frozen section diagnosis. In ...2010, we established a real-time nonrobotic telepathology system in a very active cancer center for daily frozen section service. Herein, we evaluate its accuracy compared to direct microscopic interpretation performed in the main hospital by the same faculty and its cost-efficiency over a 1-year period. From 643 (1,416 parts) cases requiring intraoperative consultation, 333 cases (690 parts) were examined by telepathology and 310 cases (726 parts) by direct microscopy. Corresponding discrepancy rates were 2.6% (18 cases: 6 0.9% sampling and 12 1.7% diagnostic errors) and 3.2% (23 cases: 8 1.1% sampling and 15 2.1% diagnostic errors), P = .63. The sensitivity and specificity of intraoperative frozen diagnosis were 0.92 and 0.99, respectively, in telepathology and 0.90 and 0.99, respectively, in direct microscopy. There was no correlation of error incidence with postgraduate year level of residents involved in the telepathology service. Cost analysis indicated that the time saved by telepathology was $19,691.00 over 1 year of the study period, whereas the capital cost for establishing the system was $8,924.00. Thus, real-time nonrobotic telepathology is a reliable and easy-to-use tool for frozen section evaluation in busy clinical settings, especially when frozen section service involves more than one hospital, and it is cost-efficient when travel is a component of the service.
•Analysis of frozen sections performed by real-time nonrobotic telepathology and direct microscopy.•A unique setting of resident/faculty cooperation team.•Cost analysis of using a relatively inexpensive telepathology system.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Various grafting materials have been used in oral and periodontal surgeries to augment and rebuild bone intraorally. Calcium sulfate, a synthetic material, also known as an alloplast, has been used ...for decades in orthopedics, plastic surgery, and oncologic and maxillofacial surgeries for the treatment of osseous deficiencies caused by trauma or inflammation. Biphasic calcium sulfate provides benefits as a short-term space maintainer. Use of biphasic calcium sulfate as the sole material are limited to relatively small osseous defects surrounded by at least 3 bony walls (eg, extraction sockets). Thus, for augmenting large and more complex bone deficiencies Bond Apatite, a composite graft formulation, is indicated. This work will review the various clinical applications of Bond Apatite as an alternative to other graft materials.
Implant planning has moved in recent years to virtual planning with a CBCT scan and fabrication of a surgical guide based on that virtual planning. Unfortunately, positioning based on prosthetics is ...typically missing from the CBCT scan. Use of a diagnostic guide fabricated in office permits information from ideal prosthetic positioning to improve virtual planning and subsequent fabricated of a corrected surgical guide. This becomes more important when insufficiencies in the ridges horizontal aspects (width) will require ridge augmentation to allow later implant placement. This article discusses a case with insufficient ridge width and determination of where augmentation is required to house implants in ideal prosthetic positions, the subsequent grafting, implant placement and restoration.
The formation of block copolymer nanoparticles is commonly obtained by switching solvent quality from good solvent for both blocks to a selective solvent for one block. The effect of the selective ...solvent on particle dimension, shape and inner structure has been analyzed in detail, instead less attention has been focused on the role of the common solvent. Poly(ethylene oxide)-block-poly(lactic acid) (PEO-b-PLA) is widely used for the preparation of nanometric drug delivery systems and the control of the particle morphology has relevant effects on bioactivity. In this work we investigate the effect of using different common solvents (acetone, dioxane, tetrahydrofuran, dimethylformamide) on the self-assembly behavior of narrowly dispersed PEO-b-PLA copolymers, synthesized by metal free ring-opening polymerization, with large variation of molecular weight of the hydrophobic block (from 65 to 1300 lactic units). Dynamic light scattering (DLS) and cryo-electron microscopy (cryo-EM) analyses of PEO-b-PLA nanoparticles reveal that their size and shape are strongly dependent on the hydrogen bonding ability of the common solvent used in the self-assembly process. As consequence of these variations, also the cytoxicity of the nanoparticles is affected.
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•A library of PEO-b-PLA copolymers has been synthesized by DBU catalyzed ROP.•The self-assembly of PEO-b-PLA copolymers has been realized in a variety of common solvents.•The hydrogen bonding ability of the solvent has a relevant effect on the self-assembly.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
