Background. Splinting of teeth is performed for effective distribution of loads in mobile teeth and to lower the stress applied to compromised teeth. Biomechanics cannot adequately explain load distribution around natural teeth. This study aimed to compare the distribution pattern and magnitude of stress and strain around splinted and non-splinted teeth with compromised periodontium using three-dimensional (3D) finite element analysis (FEA). Methods. Six mandibular anterior teeth were scanned and data were registered in CATIA® and then SolidWorks® software programs. The jawbone was also designed. In the second model, the teeth were splinted with fiber-reinforced composite (FRC). The models were then transferred to ANSYS® software program and after meshing and fixing, 100-and 200-N loads were applied at zero and 30° angles. The magnitude and distribution of stress and strain in the periodontal ligament (PDL) and the surrounding cortical bone were determined. Results. A significant reduction in stress was noted in cortical bone around central and lateral incisors while an increase in stress was noted around the canine tooth after splinting. All these changes were more significant under 100-N load compared to 200-N load and greater differences were noted in response to the application of oblique loads compared to vertical loads. Conclusion. Splinting decreased the magnitude of stress and strain in teeth close to the center of splint and increased the stress and strain in teeth far from the center of splint. Adequate bone support of canine teeth must be ensured prior to selection of splinting as the treatment plan for the anterior mandible since it increases the longevity of all the teeth.

Background: The aim of this study was to evaluate the retention of implant‑, supported overdentures with different attachment systems. Materials and Methods: In this in vitro study edentulous model with 2 Straumann implant in symphyseal region was used to make an overdenture with different attachment systems. (Dolder bar with 1 and 3 metal clips, Hader bar with 1 and 3 plastic clips, ball on bar with 2 and 4 plastic caps, Locator, Rhein plastic caps and Eleptical matrix). Retention values were recorded by universal testing machine with a cross speed of 50. 8 mm/min in vertical, posteroanterior, and lateral direction. Repeated measure ANOVA and Duncan tests were used for the data analysis (α,=0. 05). Results: There was a statistically significant difference between the retention values of studied attachments in different dislodgment directions (P < 0. 05). The highest and lowest retention were recorded for 4 balls on bar (56. 71 N) and Rhein pink caps (27. 89 N) in the vertical direction. Three metal clips (61. 43 N) and Rhein pink cap (24. 77 had the highest and lowest retention force in the posteroanterior direction. In the lateral direction, 4 balls on bar (62. 68 N) and 1 plastic clip (32. 27 N) showed the highest and lowest retention, respectively. Conclusion: If the higher retention force has been considered for implant‑, supported overdenture attachment selection, the clinician can use splinted bar or ball on bar superstructure.

Background & Aim: Due to the great influence of impression techniques on dimensional accuracy of implant master casts and existence of controversy about the best impression technic, this study aimed to evaluate the influence of four impression techniques on dimensional accuracy of implant's master cast. Methods & Materials: In this experimental study, five implant's analogues on laboratory models was used to transfer the positions of implants with four impression techniques. For each impression technique, 4 master casts was made. Impression techniques used included: I - non splinted + perforated tray, 2- non splinted + open tray, 3- splinted + open tray, 4- splinted + perforated tray. Dimensional accuracy of master casts fabricated with different impression techniques, was evaluated with comparison of distance of indicated points on the implant's analogues between laboratory model and master casts. The distance between points was calculated on 3 axis (X, Y, Z) and special position of points was also calculated. This evaluation was calculated with micrometer in precision of I micron. Data were evaluated with SPSS software and Repeated Measure analysis.Results: Significant difference was not found between the influences of four impression techniques on dimensional accuracy of implant's master casts. None of the four impression techniques didn't transfer precisely the location of indicated points of laboratory model to master casts on X, Y, Z axes or spatial position of them.Conclusion: Acrylic resin splinting didn't show significant influence to augment the dimensional accuracy of master casts, so the non splinted technique is advisable because of simplicity and economic. Although more investigations is needed in this issues to augment the dimensional accuracy of master casts and approach to oral situation for increasing the clinical relevance.

Background. A controversial issue in implant dentistry is decision making about splinting of adjacent implants in segmental tooth replacement which is usually occurred during the planning stage. The aim of this presentation is to review the latest literature on splinting versus nonsplinting the restorations of adjacent dental implants, and discussing the advantages and disadvantages of either option. It will be tried to provide the practitioner a decision tree when they encountered such situation. Methods. A comprehensive literature review is conducted for articles evaluating the success of splinted and nonsplinted dental implants. Results. Both options have their outcomes, and no evidence is found to suggest one of them to reach the best result. However, less technical complications have been found with splinted restorations. Conclusions. Both splinting and nonsplinting are valid options for restoring adjacent implants. Nonetheless, considering the several factors related to the patient are crucial to achieve the best possible outcomes and lowest risks for complications.

Backgrounds: Rheumatoid arthritis is a chronic inflammatory disease and rest splinting may reduce inflammation and swelling and pain in acute joints, the aim of this study is to determined effect of Rest splint in reduction of inflammation in wrist and hand joints of rheumatoid arthritis patients.Materials and methods: in 50 rheumatoid arthritis patients (according to ACR criteria 1987) prescribed thermoplastic rest splint in either hands randomly for one month at night, and before and after study assessment of pain (VAS) and duration of morning stiffness and swelling and range of motion of wrist and PIP and MCP joints and hand volume and grip strength performed.Results: in final assessment of splinted hand there was significant less pain (p=0.002), less morning stiffness (p=0.01), less swelling (p=0.0003), less tenderness (p=0.004) and better range of motion of wrist (p=0.0005). In addition in final assessment in splinted and unsplinted hands there was less swelling (p=0.006), less tenderness (p=0.03) and better range of motion of the wrist (p=0.04) in splinted hands, but there was not any significant change in pain and morning stiffness, joint count, flexion of MCP and PIP joints, hand volume and grip strength.Conclusions: according to results we offer more using of this splint in treatment of RA patients.

The aim of this work is to describe a case of severe disparallelism between two implants supporting a cement‑ retained bridge, placed in the maxilla, employing two custom‑ angled abutments. Fractured abutment screw and fractured abutment involved two implant restorations in the maxilla. Once prosthetic components have been removed, a new prosthetic rehabilitation has been planned. The divergence between the implants was measured, obtaining an angle of divergence of 39° . Then, two custom‑ angled titanium abutments and two metal‑ ceramic splinted crowns were realized.

Background & Aim: The reproduction of superstructures that exhibits the best passive fit when connected to multiple abutments is one of the major objectives in making implant supported prosthesis. Taking accurate impression is the most important requirement in order to ensure passive fit. The aim of this study was to review selected databases in search of journal articles describing the best implant impression techniques or their modifications that can increase the accuracy of the impression and finally a passive supra-structure reproduction. Materials & Methods: Language restriction was applied in order to select articles in English language only. Based on our strategy, search started from Cochrane Oral Health Group’s Trials Register, followed by searching PubMed and Medline databases. Hand searching was conducted for several dental journals. We checked the bibliographies of relevant clinical trials and review articles in search of studies that may not have been included in those hand searched journals. Several implant manufacturers’ product catalogues as well as their instruction manuals were searched for relevant information. Results: A total of 92 articles were identified. Twelve of them were case-report articles that presented modified techniques. Another 50 presented detailed statistical comparison and were suitable for inclusion in this review. No RCT and Meta analysis papers were identified. Conclusion: Based on the reviewed articles it can be suggested that: Direct or open tray technique is more accurate procedure than indirect or close tray technique for duplicating oral conditions in the master cast. Polyether and polyvinylesiloxane (PVS) impression materials are more suitable for taking impression of dental implants. In case of multiple implants, splinted technique showed no advantages over non splinted techniques.

Introduction: Dental trauma mainly affects the anterior teeth, which can have significant effects on tooth function, aesthetics, and speech. Extrusion refers to the relative tooth displacement out of the socket. The emergency treatment in this injury is repositioning the tooth and flexible splint for 2 weeks. Materials & Methods: The patient is 8-year-old boy with a chief complaint of trauma to the teeth. After confirming the diagnosis of traumatic extrusion injury, the tooth # 9 was repositioned and splinted. During one-year follow-up, root canal calcification and normal response to pulp sensibility tests were observed.