International Journal of Prosthodontics

PURPOSE: To update data on the transfer accuracy of digital implant impressions by using a coordinate-based analysis, latest intraoral scanners (IOSs) were investigated in an established clinical close model set-up. MATERIALS AND METHODS: An implant master model (IMM) of the maxilla with four implants in the posterior area (#14/#24 and #16/#26) and a reference cube was scanned with four different IOS (i700 (Medit), Primescan (Dentsply Sirona), Trios 4 and Trios 5 (3Shape) ten times each...

PURPOSE: To evaluate the adherence of three types of bacteria [Staphylococcus (S) aureus, Escherichia (E) coli, Pseudomonas (Ps) aeruginosa] and the size of the microgap of three different implant systems (JD, ORA, and Ankylos) under four different screw torque values. MATERIALS AND METHODS: Ten samples for each tested implant system were used under different torques to determine the width of the gaps. The abutments were connected to the fixtures using a universal digital wrench...

PURPOSE: The aim of the present study was to investigate the influence of three post-and-core systems and two crown materials on stresses in restored premolars using Finite Element Analysis (FEA). MATERIALS AND METHODS: A maxillary second premolar 3D model was created in SolidWorks 2014 (Dassault Systémés). Severe loss of tooth structure was simulated with six restorative options: 1) glass-fiber-reinforced composite post and composite core (GFRC)+CAD/CAM leucite-reinforced glass-ceramic crown (LRC); 2) carbon-fiberreinforced composite post and composite core (CFRC)+LRC; 3) metal cast post-and-core (MPC)+LRC 4) GFRC+CAD/CAM composite resin crown (CC); 5) CFRC+CC; 6) MPC+CC...

PURPOSE: To evaluate the effect of cheek retractors on the accuracy of capturing peripheral borders in totally edentulous digital scans by comparing the conventional impression technique to digital scans made using two different cheek retractors. MATERIAL AND METHODS: Sixteen edentulous maxillary impressions were made using three techniques: the conventional impression technique, using modeling thermoplastic compound and zinc oxide eugenol paste; the digital intraoral scanning technique using the DIO scan retractor (DIO); and using the Br...

PURPOSE: To compare the fracture load of two framework materials, zirconia and a new fiber-reinforced composite (FRC), for full-arch implant-supported rehabilitations using various cross- sections. MATERIAL AND METHODS: A cobalt-chromium metal model simulating the all-on-four concept and including 2 anterior straight and 2 posterior 45- degree angled multi-unit digital implant analogs was manufactured. 4 straight multi-unit abutments were screwed onto the implant analogs...

PURPOSE: The aim of this study was to evaluate the influence of restoration bonding and type of preparation on load bearing capacity of a tooth restored with indirect glass ceramic or hybrid ceramic occlusal veneer restoration. MATERIALS AND METHODS: Occlusal surfaces of extracted human molar teeth were prepared for indirect occlusal veneers with or without circumferential chamfer. The occlusal veneers were milled either from CAD/CAM hybrid ceramic (HC) Cerasmart (GC), or lithium-disilicate glass ceramic (LDGC) IPS e...

PURPOSE: The aim of this study was to determine and compare color differences of pressed lithium disilicate ceramic specimens after repeated firing cycles. An additional objective was to determine and evaluate correlation of CIEDE2000 values analyzed by X-Rite Color i5 Spectrophotometer, VITA EasyShade Advance 4.0 and Adobe Photoshop. MATERIAL AND METHODS: Tile specimens (N=36) with 8 x 10 x 1.5mm dimensions were prepared by IPS e.max Press lithium disilicate MT Monochromatic ingots and IPS e...

PURPOSE: To develop a system for assessment of the status of a tooth to receive a full coverage crown and depict it on a measurable scale, and to validate its use by assessing examiner reproducibility. METHODS: The index was developed based on the inputs from experts in the field with a consensus on factors (4 periodontal, 2 endodontic, and 4 prosthodontic), stages of severity (stage 1 to stage 4), assigned scores, and relative weights pertaining to varied clinical scenarios...

PURPOSE: To investigate the medium-term survival of Dalbo-Rotex retention elements, identify potential risk factors for complication or loss, and to consider economic factors. MATERIALS AND METHODS: Patients treated with Dalbo-Rotex retention elements in a university setting were retrospectively identified and examined. Clinical data comprised assessments of the dental, periodontal, endodontic, and prosthetic situation, including radiographic analysis. Patient satisfaction was quantified with visual analog scale questionnaires...

PURPOSE: The purpose of this work is to observe the effect of the cavity design of the direct composite restoration on a real case of the patient's tooth structures after applying his mandibular kinematics with finite element analysis. MATERIALS AND METHODS: Four complex maxillomandibular models of teeth 17 and 47 were constructed from the patient's cone-beam acquisition and the patient's kinematic data recorded with Modjaw® were added. Different shapes and sizes of mesio-occluso-distal (M...

BACKGROUND: Maxillary premolars have a unique anatomical location. This is an CBCT based study where the suitability of maxillary premolars for immediate implant placement (IIP) is evaluated. Based on prosthetically driven treatment treatment planning a simple classification system is put forth. MATERIALS AND METHODS: 150 CBCTs of maxillary first premolars were analysed in BlueskyBio software. The topographic position of the tooth was determined by analysing the dimensions of the buccal and lingual cortical plates, the distance between the bucco-lingual plates and the residual bone height from the root apex to the floor of the sinus...

PURPOSE: To determine the frequency of insert changes for combined maxillary and mandibular implant overdentures (IOD) using the Locator Legacy system. A secondary objective was to assess the survival of dental implants with IODs. MATERIALS AND METHODS: This retrospective audit reviewed clinical records with up to 12 years follow up from 785 patients who received IODs using the Locator system at a dental hospital. From these, 151 had a combined maxillary opposed by a mandibular IOD and from this, 37 had data retrieved using a minimum data set...

PURPOSE: To evaluate the circumferential bone level and the morphological changes in posterior mandibular ridge of mandibular overdenture wearers submitted to conventional and immediate loading through cone beam computed tomography (CBCT) at 1 and 3 years. MATERIAL AND METHODS: Twenty participants who received 2 NDI (Facility - 2.9x10 mm) were randomly allocated to the conventional loading (CL: n=10) or immediate loading (IL: n=10) groups. CBCT scans were performed in each group to analyze the vertical (VBL) and horizontal (HBL) bone level around the implants, analyzed together with the posterior bone remodeling of the mandible measured at distances of 5, 10, 15, and 20 mm from the mental foramen (L1-L4)...

PURPOSE: Several procedures are performed to achieve optimal esthetic results in single-tooth implants. However, there is discordance regarding the potential benefit and risks of immediate implant loading/provisionalization. The aim of this prospective case series is to investigate the effect of immediate provisionalization of single-tooth implants at healed sites for periimplant soft-tissue conditions, focusing on papilla formation around single implants. MATERIALS AND METHODS: Twelve patients received a total of 12 implants in the incisor, canine or premolar region of the upper and lower jaw at healed sites with immediate chair-side provisionalization...

PURPOSE: To evaluate the surface characteristics, accuracy (trueness and precision), and dimensional stability of tooth preparation dies fabricated using conventional gypsum and direct light processing (DLP), stereolithography (SLA), and polymer jetting printing (PJP) techniques. MATERIALS AND METHODS: Gypsum preparation dies were replicated according to the reference data and imported into DLP, SLA, and PJP printers, and the test data were obtained by scanning after 0, 1, 3, 7, 14, 28, and 42 days...

PURPOSE: The purpose of the study was to examine the long-term performance of bonded all-ceramic restorations, veneers in particular, in patients with Amelogenesis Imperfecta (AI). There are few studies of long-term outcome using a minimally invasive procedure in these patients. This aspect is essential when treating young patients. All-ceramic restorations, especially veneers, offer a more tissue-preserving treatment but rely on a successful bonding. Due to the defect enamel in AI patients, the bond strength is however lower...

PURPOSE: To determine whether food texture affects chewing side preference (CSP) and to investigate the relationship between CSP and masticatory factors such as occlusal contact area, bite force, and masticatory performance. MATERIALS AND METHODS: Forty-seven adults (20 women and 27 men; mean age, 24 years) participated in this study. Three types of food (chewing gum, beef jerky, and peanuts) were provided to assess CSP. Occlusal contact area was measured at various ranges of interocclusal distance, and the bite force was measured...

Int J Prosthodont 2024. doi: 10.11607/ijp.8475.

PURPOSE: To analyze the micro-gap changes between hybrid abutment crowns made of two materials and three internal taper connection implants each having different connection designs before and after thermodynamic loading. MATERIALS AND METHODS: A total of 30 implants; ten each of Straumann Bone Level Implant-RC [STR]; GC AADVA Implant [AAD] and Astra-Tech OsseoSpeed EV [AST]were included in this laboratory study. Each implant has an internal taper connection, but their designs are slightly different...

In our previous test model, the abutment teeth and the model base were printed with resin and bonded with a polyether material. Some abutment teeth fractured during the mechanical load test. Therefore, the aim was to develop and to evaluate a new model under mechanical loading until fracture with zirconia FPD frameworks. Up to a fracture load of 1636 N, neither the artificial abutment teeth nor the base model fractured. Furthermore, the artificial abutment teeth did not detach from the base model. Therefore, the model should be suitable for mechanical testing of most ceramic-based framework materials for three-unit FPDs...