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Background The use of intraoral scanners (IOS) has facilitated the use of digital workflows for the fabrication of implant-supported prostheses not only for single missing teeth, but also for multiple missing teeth. However, the clinical application of IOS and computer-aided design/manufacturing (CAD/CAM) in implant-supported prosthodontics remains unclear. This study aimed to compare the accuracy of digital and silicone impressions for single-tooth implants for bounded edentulous spaces and two-unit and three-unit implant-supported fixed dental prostheses for free-end edentulous spaces. Methods This study enrolled 30 patients (n = 10 for each of the three groups) with an average age of 61.9 years. Conventional silicone-based and digital IOS-based impressions were made for all patients, and the implant superstructures were fabricated. We measured the scan-body misfit and compared the accuracy of the impressions for single-unit, two-unit, and three-unit implant prostheses with a bounded edentulous space by superimposing the standard triangulated language (STL) data obtained from IOS over the STL data of the plaster model used for final prosthesis fabrication. The scan bodies of the superimposed single-molar implant, two-unit implant prosthesis without teeth on the mesial side, two-unit implant prosthesis without teeth on the distal side, three-unit implant prosthesis without teeth on the mesial side, and three-unit implant prosthesis without teeth on the distal side were designated as A, B1, B2, C1, and C2, respectively. The misfit for each scan body was calculated and the accuracies were compared using the Tukey–Kramer method. Results The average scan-body misfit for conditions A, B1, B2, C1, and C2 was 40.5 ± 18.9, 45.4 ± 13.4, 56.5 ± 9.6, 50.7 ± 14.9, and 80.3 ± 12.4 μm, respectively. Significant differences were observed between the accuracies of A and B2, A and C2, and C1 and C2 (P Conclusions IOS and CAD/CAM can find clinical applications for implant-supported prostheses of up to three units for a bounded edentulous saddle. The use of IOS could render implant treatment easier, benefiting both the surgeons and patients. Prosthesis maladjustment may lead to peri-implantitis and prosthetic fracture. Therefore, further validation of the accuracy of IOS impressions is required in patients with multiple missing teeth in long-span implant prostheses.

Objective Missing maxillary lateral incisors is a common developmental anomaly and often creates a major esthetic problem due to their position in the dental arch. Treatment in such cases depends on either creation of space followed by prosthetic replacement or closing the space and replacing the missing lateral incisors by canines. In this report we highlight some of the key factors which should be considered for replacement of missing lateral incisors using single tooth implant. Methods This clinical report describes the treatment of a patient with bilateral missing maxillary lateral incisors. An interdisciplinary approach involving Orthodontist, implant surgeon and prosthodontist was used in the treatment. Results At the end treatment, the patient presented with class I molar and canine, normal overbite and overjet, and good facial esthetics with canine protected occlusion. Conclusion When indicated, space opening and replacement of missing lateral incisors with implant supported tooth substitution may provide excellent esthetics and functional results.

To compare the active tactile sensibility (AST) between natural teeth and implant dentures, and explore the risk factors. To establish a database of normal tactile thresholds of natural teeth, and integrate the results from experiments. 50 patients underwent posterior dental implant restoration. A healthy group was also enrolled as control. Patients were firstly placed in semi-supine position with soothed tension and wore ear pads and goggles. Next, T-scan II digital occlusal analysis system (Tekscan,USA). The test was performed in double-blind way and recorded by the third. Results were analyzed using SPSS software and P value less than 0.05 was considered as statistically significant. Active tactile sensibility showed no statistically significant difference between natural teeth and dental implants among males and females (P > 0.05). However, there was difference between the natural tooth and implant tooth (P < 0.01), and there was also statistically significant difference between the front tooth and the back of the natural tooth and implant tooth (P < 0.01). There is no significant difference in the determination of the active tactile sensitive threshold difference between the implanted tooth and the natural tooth, which could serve as a comprehensive guiding for clinical strategies of tooth implantation.

Nitinol metal alloy that changes shape according to temperature has been in clinical use at select clinics worldwide for the past 2 years and is now released for general use. The Smileloc Abutment and nitinol sleeve enable "cementless," "screwless," crown fastening that saves time and cost with the prospect of replacement of much of the present, sometimes troublesome, anthropic, soon to be anachronistic, technology.

AIM This randomized controlled clinical trial (RCT) aimed to compare the accuracy of implant positions between static computer-assisted implant surgery (CAIS) and freehand implant surgery in a single edentulous space. MATERIALS AND METHODS Sites with single edentulous spaces and neighbouring natural teeth were randomized into static CAIS or freehand implant surgery groups. In both groups, digital implant planning was performed using data from cone beam computed tomography (CBCT) and surface scans. In the static CAIS group, a surgical guide was produced and used for fully guided implant surgery, while in the freehand group, the implants were placed in a freehand manner. Postoperative CBCT was used for nine measurements representing the deviations in angles, implant shoulders and apexes between planned and actual implant positions. RESULTS Fifty-two patients received 60 single implants. The median (IQR) deviations in angles, shoulders and apexes were 2.8 (2.6)°, 0.9 (0.8) mm and 1.2 (0.9) mm, respectively, in the static CAIS group, and 7.0 (7.0)°, 1.3 (0.7) mm and 2.2 (1.2) mm, respectively, in the freehand group. Statistically significant differences were found in 6 out of nine measured parameters using Mann-Whitney U test (p

Anterior immediate implant placement (IIP) has many biological and esthetic challenges, including inevitable soft and hard tissue loss after extraction. Previous literatures have discussed the facial bone architecture and defective socket classification. However, none of them discussed the depression of the cervical root area which can be seen frequently after IIP in type IIB and U-shaped defective sockets. In our limited experiences, we found that the labial interproximal bone edges of type IIB and U-shaped defect dominated the esthetic result after IIP. With more labial projection of the interproximal bone present, better esthetic result could be expected in the facial aspect. With adequate evaluation of this osseous scalloping before IIP, both patient and clinician could have a comprehensive understanding of the final esthetic result. This article also detailed the process of patient selection, diagnosis, surgical options, and executions required to achieve functional and esthetic success with IIP and provisionalization.

Statement of problem Whether the presence of a screw access channel on the occlusal surface of a lithium disilicate cement-retained single tooth implant restoration reduces its fracture rate is unclear. Purpose The purpose of this randomized controlled clinical trial was to compare the fracture rate of lithium disilicate cement-retained posterior single tooth implant restorations with or without screw access channels. The study also evaluated whether the crown dimensions and location of the occlusal screw access channel would affect the fracture rate. Material and methods A split-mouth study was conducted where 40 participants having 2 implants placed to restore single missing posterior teeth with crowns were enrolled. Implants were randomly allocated into a conventional crown group or a screw access group, receiving cement-retained restorations fabricated from lithium disilicate glass-ceramic with and without an occlusal screw access channel. Crown dimensions were recorded in millimeters from the designing software. Follow-up evaluations were made at 3, 6, and 12 months by observing visible cracks or fractures of the crowns. The Kolmogorov-Smirnov test of normality was used. Comparisons were carried out by using the Student and Welch t tests (α=.05). Results After a 12-month follow-up period, no crowns fractured or revealed visible cracks, resulting in a 100% success rate. No statistically significant differences were found between the conventional crown group and screw access channel group in all crown dimensions (P>.05). Conclusions The presence of an occlusal screw access channel did not affect the short-term fracture rate of lithium disilicate cement-retained single implant–supported posterior crowns. The amount of axial cantilever, occlusal ceramic thickness, and location of the screw access channel on the occlusal surface of the restoration have no effect on its fracture rate.

Objective: Over the last decades, techniques and materials have evolved with the improvement in digital technology. Computer-aided impressions have been transforming the dental implant field with these developments. The aim of this in vivo study was to compare the accuracy and time efficiency between two intraoral scanning systems in single tooth implant treatment. Material and Method: 10 patients with single tooth bone level implant (Straumann, Basel, Switzerland) received one conventional impression with polyvinyl siloxane and three scans with 2 different intra-oral scanners (CEREC AC Omnicam and Straumann CARES IOS). The time required for the impressions was measured at this stage. The casts obtained from conventional impressions were scanned as the master model to evaluate accuracy. Digital impression files were analyzed using software (Geomagic Control). Independent Samples Test was performed for trueness and precision. One-way ANOVA was executed for time efficiency. Least significant difference test for post hoc comparison was conducted (p0.05), but a statistically significant difference was found in the time efficiency (P

This study evaluated the von Mises stress (MPa) and equivalent strain occurring around monolithic yttria-zirconia (Zir) implant using three clinically simulated finite element analysis (FEA) models for a missing maxillary central incisor. Two unidentified patients' cone-beam computed tomography (CBCT) datasets with and without right maxillary central incisor were used to create the FEA models. Three different FEA models were made with bone structures that represent a healed socket (HS), reduced bone width edentulous site (RB), and immediate extraction socket with graft (EG). A one-piece abutment-implant fixture mimicking Straumann Standard Plus tissue level RN 4.1 X 11.8mm, for titanium alloy (Ti) and Zir were modeled. 178 N oblique load and 200 N vertical load were used to simulate occlusal loading. Von Mises stress and equivalent strain values for around each implant model were measured. Within the HS and RB models the labial-cervical region in the cortical bone exhibited highest stress, with Zir having statistically significant lower stress-strain means than Ti in both labial and palatal aspects. For the EG model the labial-cervical area had no statistically significant difference between Ti and Zir; however, Zir performed better than Ti against the graft. FEA models suggest that Ti, a more elastic material than Zir, contributes to the transduction of more overall forces to the socket compared to Zir. Thus, compared to Ti implants, Zir implants may be less prone to peri-implant bone overloading and subsequent bone loss in high stress areas especially in the labial-cervical region of the cortical bone. Zir implants respond to occlusal loading differently than Ti implants. Zir implants may be more favorable in non-grafted edentulous or immediate extraction with grafting.

In the anterior region, the common reason for tooth loss is due to traumatic injury or congenital anomaly. Loss of a single tooth may cause functional and esthetic deficits to the patient. There are different treatment options available for replacing a missing incisor. Implant dentistry should be considered as first treatment alternative for replace a missing tooth. This case report presents the replacement of a missing maxillary left central incisor in a compromised site with dental implants along with bone graft followed by frenectomy to obtain a good clinical result and for better function and esthetics of the patient.

The replacement of one tooth using one implant involves a set of unique criteria for long-term success. Successful therapy should be based on long-term function and health of the adjacent tissues. Sections of this article examine these critical criteria that when working together can result in successful long-term tooth replacement.

Agenesis, the absence of permanent teeth, is a common occurrence among dental patients. The total incidence of tooth agenesis is about 4.2% among patients that are seeking orthodontic treatment and with the exception of third molars, the maxillary lateral incisors are the most common congenitally missing teeth with about a 2% incidence. Esthetically correcting congenitally missing maxillary lateral incisors is a common challenge that every orthodontist and dental team will face, and dentists must consider the treatment options that are most appropriate for each patient. This paper describes the therapeutic use of osseointegrated implants to replace congenitally missing upper lateral incisors. Highlighting the importance of the Orthodontic/Restorative interface.

Congenitally missing teeth are frequently presented to the dentist. Interdisciplinary approach may be needed for the proper treatment plan. Several treatment options exist for the replacement of congenitally missing lateral incisors.This case report addresses the fundamental considerations related to replacement of a congenitally missing lateral incisor by a team approach. Keywords: congenitally missing lateral incisor, interdisciplinary treatment, dental implant.

Background: This study aims to assess, with regard to marginal bone level (MBL), whether the outcome of immediate implant placement in bony defects in the esthetic zone was non-inferior to delayed implant placement after 1 year.Methods: Forty patients with a failing tooth in the esthetic zone and a labial bony defect of >= 5 mm after removal of a tooth were randomly assigned for immediate (n = 20) or delayed (n = 20) implant placement. Second-stage surgery and provisionalization occurred after 3 months of healing. Follow-up was at 1 month and 1 year after definitive crown placement. The study was powered to detect a difference in MBL of >0.9 mm. Buccal bone thickness, soft tissue peri-implant parameters, esthetic indices, and patient satisfaction were also assessed.Results: One year after definitive crown placement, MBL loss was 0.56 +/- 0.39 mm mesially and 0.74 +/- 0.51 mm distally for the immediate placement group and 0.51 +/- 0.43 mesially and 0.54 +/- 0.45 distally mm for the delayed placement group, respectively (not significant). Regarding differences in means, non-inferiority was observed after 1 year (difference in mean for immediate versus delayed: mesially 0.04 mm [95% confidence interval (CI) = -0.22 to 0.30 mm, P = 0.40]; distally 0.21 mm [95% CI = -0.10 to 0.51 mm, P = 0.58]). No significant differences in the other outcome variables were observed.Conclusions: Immediate implant placement with delayed provisionalization was non-inferior to delayed implant placement with delayed provisionalization in labial bony defects of >= 5 mm regarding change in MBL. Although not powered for other outcome variables, no clinically relevant differences were observed in these variables.

Purpose To correlate patients’ satisfaction and dentists’ observations regarding two abutment designs used for single crowns in the esthetic zone: a divergent one (control) and a curved one (experimental), with special emphasis on muco-gingival esthetics. Materials and Methods Twenty-six patients with nonadjacent missing teeth in the esthetic zone were enrolled in a randomized clinical trial (within-subject comparison). Two implants placed in each were restored using abutments of different geometry. Patients’ appreciation was assessed on a visual analog scale (VAS) by recording answers to three questions, and dentists’ appreciation was determined by means of the Pink Esthetic Score (PES) at T0 (crown cementation, baseline) and at T12 (1 year post-cementation). ANOVA with post hoc analysis was used to identify differences between groups and at different moments in time. Pearson correlations were calculated between all variables, both at T0 and at T12. Results No statistically significant differences were found at any time between the control and experimental abutment design, either for the PES or for the VAS score. PES slightly improved after 1 year, as did the VAS rating related to functioning with the implant-crown compared to the natural teeth. All PES and VAS scores demonstrated highly significant correlation. Both patient satisfaction and professional appreciation of muco-gingival conditions after single implant treatment in the esthetic zone were high; however, the curved, experimental abutment design performed no better than the conventional, divergent type. Conclusion Curved abutment design does not significantly impact crown or gingival esthetics as assessed by PES and VAS scored by dentists and patients, respectively.

In the maxillary arch from premolar to premolar, 26 single dental implants were inserted in fresh extraction sockets and immediately provisionalized. The bone-to-implant gap was grafted with a bovine bone mineral. After 3 months, definitive ceramic crowns were placed. At baseline and after 1 year, the soft tissue horizontal width, mesiodistal papillary level, midfacial gingival level, and pink esthetic score were evaluated. No statistical differences were found between baseline and 1 year for all parameters. Immediate single-tooth implants, with immediate restoration, are capable of maintaining the soft tissue contour and esthetics compared to the pretreatment status.

Aesthetic considerations continue to become more relevant in dentistry, with patients becoming increasingly discerning about the results achieved from a cosmetic point of view. As such, the orthodontic/prosthodontic interface, in relation to managing congenitally absent maxillary lateral incisors, requires an integrated management approach, ensuring an aesthetic as well as a functional and stable outcome. This article explores the key orthodontic and prosthodontic approaches to achieve optimal treatment outcomes.

To test whether or not pink veneering of the submucosal part of zirconia abutments influences clinical, microbiological and histological outcomes of cemented implant-supported single crowns (ISSC).A total of 20 patients with one single-tooth implant in the esthetic zone were included. Implants were randomly restored with either pink-veneered zirconia abutments (test group; n = 10) or non-veneered white zirconia abutments (control group; n = 10) and with adhesively cemented all-ceramic crowns. At the 6-month follow-up, soft tissue biopsies were prepared for histological evaluation and microbiological samples were collected around abutments and the respective contra-lateral teeth (in 10 of 20 patients). One year after the initiation of loading, clinical parameters were assessed. Robust linear mixed model and cumulative linked mixed model analyses were performed to investigate the effect of group and time-point on clinical and biological outcomes.Clinical evaluations revealed stable peri-implant soft tissues in terms of probing pocket depth, but a high BOP index (87.5% control; 80.0% test). No statistically significant differences were observed between the test and control group for any outcome measure (P 0.05). No major biological complications occurred during the observation period. Histological samples revealed a remarkable degree of inflammation in both groups without clear differences in qualitative histological features. Microbiological evaluation demonstrated a slightly higher bacterial count at implants compared to natural teeth at one year of loading without marked differences between groups.Limited by a small sample size and a relatively short observation period, pink-veneered zirconia abutments exhibited similar clinical, histological and microbiological outcomes as non-veneered zirconia abutments supporting cemented single crowns.

Introduction: Minor rotation of impression coping secured in the impression is an avoidable error that needs to be minimized to ensure precise positioning of implant analog in master cast. Aim: The aim of the study was to compare the precision in obtaining master casts by improving the stability of impression copings in the impression with the use of tray adhesive along various surface treatments to increase surface area and by mechanical locking. Materials and Methods: A total of 60 samples were made (15 samples for each group). A total of 15 samples for Group I were prepared with untreated impression copings, 15 samples for Group II with impression copings treated and modified by application of tray adhesive only. Group III includes 15 samples which were fabricated with impression copings modified by making four vertical grooves on surface of impression coping and coated with adhesive. Group IV had 15 samples which were fabricated with impression copings sandblasted with 50 µm aluminum oxide powder and coated with adhesive. Profile projector was used to evaluate the rotational accuracy of the implant analogs by comparing Molar Implant Angle (MIA) and Premolar Implant Angle (PIA) of test samples with reference model. One-way ANOVA and Student t-test were used to analyze the data. Results: One-way ANOVA didn’t show any significant differences for both MIA and PIA between the Groups I, II, III and IV. Student’s unpaired t-test revealed no significant difference in the mean MIA and mean PIA. Conclusion: Though results were statistically non-significant, all types of surface treatments of the impression copings showed more accurate transfer than those with no treatment. Sandblasted and adhesive coated impression copings showed minimum amount of rotation followed by those with vertical slots and adhesive coated impression copings.

Background Flapless implant placement using surgical templates may guarantee predictable and esthetic results provided that preplanned implant positions are transfered precisely into surgical reality. Purpose The study aims to investigate the effect of three-dimensional accuracy in guided implant surgery on the esthetic outcome of single-tooth implants in the anterior maxilla. Materials and Methods Single-tooth implants for delayed replacement of upper incisors were inserted in 27 patients using stereolithographic templates. Superimposition of postoperative cone beam computed tomography (CBCT) scans allowed assessment of positional inaccuracy at the implant shoulder and apex, as well as angular deviation. Objective evaluation of implant esthetics was performed after a mean follow-up of 2.3 years using the Pink Esthetic Score (PES). Results Mean deviation between planned and actual implant position was 0.84 mm at the implant shoulder and significantly correlated to average PES of 12 (p = .031). Inaccuracy toward the buccal side was most frequent (70%). Deviations ≥ 0.8 mm resulted in significantly worse implant esthetics (median PES: 9.5, interquartile range [IQR]: 8–11) compared with more accurate implant positions (median PES: 13, IQR: 12–13, p = .039). Conclusion Positional inaccuracy is low in guided implant surgery, but may however significantly compromise implant esthetics in the anterior maxilla.

The objective of this study was to assess the ability of the University of Illinois at Chicago College of Dentistry (UIC-COD) predoctoral students to provide single tooth implant (STI) prostheses in the maxillary esthetic zone. The patient's esthetic satisfaction and the correlation between prosthodontists' and patients' perspectives were examined. Twenty-seven patients were recruited for recall examinations at the UIC-COD predoctoral implant program and underwent clinical and radiographic examination with clinical photographs of the implant sites. The patients completed a semantic differential scale questionnaire. The collected information was formulated into a PowerPoint presentation for two Diplomate of the American Board of Prosthodontists to use the Pink/White Esthetic Score (PES/WES) to evaluate the esthetic outcome. Descriptive analyses, Cohen kappa test, and Spearman rank correlation coefficient test were performed. The average PES/WES were above 6.0 (out of 10). The median for the patient satisfaction and esthetic outcome questionnaires were 10 and 9, respectively, on a scale with 10=highest. There was a medium and positive correlation between prosthodontists' and patients' perspectives in esthetic outcome. This study found that, with strict guidance and proper selection criteria, predoctoral students were able to provide esthetically acceptable STI prostheses in the maxillary esthetic zone and patients were satisfied with the treatment provided.

Statement of problem A consensus regarding which implant-abutment connection type would perform best in the anterior maxilla is lacking. Purpose The purpose of this systematic review was to determine the best implant-abutment connection type for anterior single-tooth implants considering esthetics, success, and survival rates. Material and methods An electronic search was conducted in MEDLINE, Scopus, Embase, and the Cochrane Library databases to identify clinical studies on single-tooth implants with external and internal hexagon, and/or Morse taper connections. These studies needed to describe at least one of the following outcomes: esthetic score, survival/success rate, or marginal bone loss. The included studies and reports were assessed for bias using the Cochrane risk of bias tool. Results Of the 891 articles identified, 29 were selected and analyzed. The most common technical complications were abutment screw loosening and crown-cement loosening, while dehiscence and recession were the most common biological complications. The most frequent complications were dehiscence for external hexagon, crown-cement loosening for the internal hexagon, and ceramic fracture for the Morse taper. Esthetics were favorable for all connections, but the internal hexagon performed better. However, better results for marginal bone loss, success, and survival were found for the Morse taper. The global annual failure rate was 0.90% and 0.2% for Morse taper, 0.3% for external hexagon, and 2.2% for internal hexagon. Conclusions This review suggests that Morse taper performs better for survival, success, and marginal bone loss. Internal hexagon performed better for esthetic parameters. Additional controlled studies are needed to provide stronger evidence because the evidence generated in this study was considered low.

Objectives Single-tooth replacement of anterior mandibular teeth is frequently complicated by insufficient bucco-lingual bone width and limited mesio-distal space available for implant placement. The aim of the present study was to assess implant esthetics in the partially edentulous anterior mandible. Material and methods Esthetic evaluation of 43 anterior mandibular single-tooth implants in 15 women and 28 men was performed using esthetic indices (PES = Pink Esthetic Score, PI = Papilla Index, SES = Subjective Esthetic Score) as well as subjective patients' Visual Analogue Scale (VAS) ratings. Clinical and radiological parameters (implant and crown dimensions, pocket depth, bleeding on probing, plaque, keratinized mucosa, marginal bone level, and distance to adjacent teeth) were tested for influence. Results Implant esthetics were judged satisfactory (PES ≤10) in 42% of implants compared with a patient satisfaction rate of 87%. Correlation between objective indices (PES/PI: rs = 0.62, PES/SES: rs = −0.73, PI/SES: rs = −0.48) was highly significant (P ≤ 0.001); however, no association to subjective patients' ratings could be observed. Type of prosthetic restoration (single crown vs. tulip-shaped double crowns), mesio-distal crown width as well as anatomic crown length significantly affected esthetic scores. Patients' judgment, by contrast, could not be associated to any prognostic factor. Conclusion Subjective patient satisfaction with implant esthetics in the partially edentulous anterior mandible is high, however, remains hard to predict or objectively quantify.

Transplantation of teeth has been done for hundreds of years. In the late 18th and early 19th century transplants of teeth between individuals were relatively common at specialist dental practices in London. Surprisingly tooth allotransplants have been found to last 6 years on average. In Scandinavia during the 1950 and 1960's autotransplantation of teeth began to be carried out under increasingly controlled conditions. These have proved to be very successful in long term studies with autotransplants surviving up to 45 years post-surgery. Recent developments in cone beam CT and rapid 3D prototyping have enabled the fabrication of accurate surgical templates which can be used to prepare the recipient site immediately prior to transplantation. This has resulted in a drastically reduced extra-oral time for the transplant teeth which can be expected to improve success rates further. Autotransplants provide significant advantages compared to single tooth implants and should be considered the treatment of choice in the growing child.

Purpose: The phenomenon of developing a certain tactile sensibility through osseointegrated dental implants is called osseoperception. Active tactile sensibility can be tested by having the subject bite on test bodies. The aim of the study was to assess the active tactile sensibility of osseointegrated single tooth dental implants according to psychophysical method of constant stimuli. Materials and methods: Twenty subjects (10 male and 10 female) with single tooth implants located in the posterior region with natural, healthy antagonistic teeth were included in the study. Ten implants were located in the maxilla and 10 in the mandible. The subjects were also divided into two age groups 30 to 40 years and 40 to 50 years, and the active tactile perception was studied according to the psychophysical method of constant stimuli. Results: The active tactile perception of osseointegrated single tooth dental implants with natural healthy antagonist revealed a threshold ranging between 24 ± 8 μ. The active tactile perception of healthy natural tooth with natural healthy antagonist revealed a threshold ranging between 12 ± 4 μ. No statistically significant results were found between different age groups (30-40 years age group and 40-50 years age group). The threshold for tactile perception was found to be similar in both male and female subjects. No statistical significance was found in the threshold between different implant locations (maxilla and mandible). Conclusion: Active tactile sensibility of implants with natural antagonistic teeth is similar to that of teeth. Implant-supported prosthesis restores jaw function more appropriately, with improved psychophysiological discriminatory ability.

The use of single tooth implant restoration in anterior and lateral regions is increasing . Replacing single missing teeth especially in the anterior region has always been a challenge for clinicians and dental technicians .With the advent of single tooth implant restoration ;an acceptable alternative is identified .Implant abutment must meet biological, functional and esthetic requirements . Biological and mechanical implant- abutment connection complications and failures are still present in clinical practice, frequently compromising oral function. Abutment screw loosening has occurred with many of other designs used for single tooth implant .The purpose of this review is to highlight the mode of failure as well as the reasons. Clinical cases, experimental and non-experimental studies were included, as well as literature reviews.

The purpose of this controlled study was to determine the impact of a single-tooth implant, fixed implant prosthesis and completely removable dental prosthesis on intelligibility, articulation and oromyofunctional behaviour. Additionally, the self-perceived overall satisfaction of the dental replacements and the effect on speech was questioned. Objective (acoustic analysis) as well as subjective assessment techniques (perceptual evaluation) were used. The satisfaction of single-tooth implant group was very high (100%) followed by a satisfaction of 87% for the fixed implant prosthesis group and 68% for the removable prosthesis group. The results of the phonetic analyses revealed a normal intelligibility and oromyofunctional behaviour in the three groups of dental replacements. Only one type of articulation disorders was observed in the single-tooth implant group, followed by three types of disorders in the removable prosthesis group and six types of disorders in the fixed implant prosthesis group. In this last group, not only 87% of the subjects showed distortions of one or more consonants but also most consonants of the Dutch language were disturbed in comparison with the single-tooth implant and removable prosthesis users. Special attention must be paid to the fricative /s/ because in more than 50% of all groups, this sound is disturbed.

Immediate implant placement is one of the treatment options in postextraction sites in anterior region. This article describes the high esthetic value of a single-tooth implant immediately placed in the anterior maxilla using a flapless approach and modifying a provisional restoration. The case reported illustrates the practical procedure involved in developing natural esthetics with modifying a provisional restoration. The technique provides an accurate impression of the soft tissue through the intraoral use of provisional restoration. The final restoration uses a custom-made titanium abutment and porcelain fused gold crown. The technique is relatively simple and provides excellent results from an esthetic point of view, which is demonstrated by the results of pink esthetic scores and white esthetic scores after 1 year.

Objectives: The aim of the present multi-center study was to evaluate the treatment outcome of immediately restored one-piece single-tooth implants with a diameter of 3 mm after 1 year. Material and methods: A total of 57 one-piece implants (NobelDirect® 3.0) were inserted in 47 patients (26 females, 21 males) with a mean age of 31 years (range: 17–76 years) at five different centers. The implants replaced maxillary lateral incisors and mandibular incisors. The implants were placed either in conjunction with tooth extraction or in healed sites, and all implants were immediately restored with a provisional resin crown. If needed, the abutment part of the implant was prepared before crown cementation. The permanent crown was placed after 1.9–14.5 months. Radiographs were taken at implant insertion as well as after 6 and 12 months to evaluate the peri-implant marginal bone level and bone loss. Moreover, plaque, bleeding on probing and complications were assessed. Results: A total of 44 patients (23 females, 21 males) with 54 implants were available for the 1-year follow-up. One implant was lost, thus the 1-year implant survival was 98%. A statistically significant mean marginal bone loss was observed between baseline and 6 months (1.1 mm, range: −0.7 to 4.4 mm; n=49) and between baseline and 12 months (1.6 mm, range: −0.8 to 4.6 mm; n=50). A total of 18% of the implants were characterized by a bone loss of more than 3 mm. No bleeding on probing was observed around 83% of the implants. Plaque was registered at 15% of the implants. The most common complications were related to the provisional crown, i.e. fracture (n=3) and loss of retention (n=3). Conclusions: A high 1-year implant survival was observed in the present study. However, the excessive peri-implant marginal bone loss around several implants indicates that this implant should be used with caution until further studies have been conducted. To cite this article: Zembic A, Johannesen LH, Schou S, Malo P, Reichert T, Farella M, Hammerle CHF. Immediately restored one-piece single-tooth implants with reduced diameter: one-year results of a multi-center stud

The primary goal of the dental surgeon is to restore function as well as esthetics, and these objectives influence both the surgical andrestorative phases of treatment.This report presents a conservative management of congenitally missing bilateral maxillary lateral incisors that was treated with amultidisciplinary approach between an orthodontist and a prosthodontist to redistribute spaces and establish buccolingual alveolarwidth by orthodontic movement of permanent canines distally in the maxillary arch followed by placement of implants to achieve adesirable esthetic result.

To our knowledge, no study has evaluated the success or survival rate of single-tooth implants that replaced missing maxillary and mandibular second molars. The purpose of the present study was to evaluate the 1- to 5-year cumulative survival rate (CSR) for single-tooth implants placed in the second molar region and the effects of associated factors.Four hundred eighty-nine patients (298 males and 191 females; age range: 23 to 91 years; mean age: 47 years) who were admitted to the Seoul National University Dental Hospital between March 2003 and July 2008 and treated with single-tooth implants in the second molar region (227 maxillary implants and 294 mandibular implants; total: 521 implants) were included in the study. Thirty-two subjects received two implants each. A 1- to 5-year CSR was calculated using a life-table analysis. A comparison of CSRs between maxillary versus mandibular implants, one-stage versus two-stage implants, short (or=8.5 mm) versus long (10 mm) implants, and standard-diameter (or=4.0 mm) versus wide-diameter (or=5.0 mm) implants was performed using Wilcoxon (Gehan) statistics. P0.05 was considered significant.Fifteen of the 521 implants were lost between insertion and the follow-up examinations. The 1- to 5-year CSR was 95.1%. There were no statistically significant differences in CSRs between implants placed in maxillas and mandibles (96.3% versus 94.9%, respectively; P = 0.084), one- and two-stage implants (95.6% versus 94.7%, respectively; P = 0.267), short and long implants (100% versus 95.1%, respectively; P = 0.582), and standard- and wide-diameter implants (93.8% versus 96.8%, respectively; P = 0.065).Within the limitations of the study, the placement of single-tooth implants in the second molar region was an effective and reliable treatment modality. Also, associated factors such as implant diameter, length, and location (the maxilla versus the mandible) may not have an impact on the long-term success of implants.

Implant-supported restorations are a commonly used treatment modality. However, insufficient data are available that compare treatment outcomes of implant restorations using different protocols. Similarly, data comparing the treatment outcomes of different implant designs are limited.This retrospective, non-randomized study evaluates 241 single implants in 241 patients (127 males and 114 females; mean age: 49.3 years; range: 45 to 75 years). Tapered-type (TAP; n = 118) and cylindric screw-type (CYL; n = 123) implants were used. Implants were grouped into the treatment categories of immediate placement, delayed placement, immediate non-occlusal loading, and delayed loading. Clinical parameters, including clinical attachment level (CAL), plaque index (PI), and bleeding on probing (BOP), were recorded at examinations at baseline (BSL) and 1 (E1), 3 (E3), and 5 years (E5) after loading with the final restoration.Eleven implants were lost (five CYL and six TAP). CAL and PI outcomes were similar for both implant types. No significant influence of implant position was found. A CAL loss of 1.5 mm was observed during the first 3 years. The type of implant and timing of placement showed no significant influence on the survival rate, whereas the failure rate was lower for immediate non-occlusal loaded implants.The type of implant, position, and timing of placement and loading did not influence the survival rate of this treatment method.

The term osseoperception describes the capability of developing a subtle tactile sensibility over dental implants. The present clinical study aims at clarifying the question of how far tactile sensibility is to be attributed to the periodontium of the natural opposing tooth of the implant.

Introduction: The aim of this review was to compare the differences between nonsurgical root canal treatment and single-tooth implants. With the emerging field of implant dentistry gaining acceptance, the choice to retain a diseased tooth through the use of root canal therapy or extract it and replace the tooth with an implant-supported crown has become controversial. Many practitioners consider the single-tooth implant as a reasonable alternative to the preservation of a diseased tooth. Methods: An extensive search of the dental literature was accomplished to identify publications related to the differences in root canal therapy and dental implants. Several comparative studies were also considered. Results: The treatment modalities were reviewed with respect to outcome measures and study design, success/failure, functional rehabilitation and psychological differences, complications related to treatment, cost differences, and factors influencing treatment planning considerations. Conclusions: With the reviewed information in hand, the practitioner should be better prepared to determine which treatment option is most appropriate for each individual patient. (J Endod 2009;35:1325‐1330)

The purposes of this study were to determine success and survival rates for implants and teeth adjacent to implants and the incidence of endodontic implantitis (E-I) (endodontic involvement in adjacent teeth causing implant failure) and implant endodontitis (I-E) (implant placement causing endodontic failure). The data were from 233 single-tooth implants placed in 116 subjects by postgraduate periodontal students with recall radiographs taken >or=9 months after implant placement. Three groups were analyzed: group A, implants with no adjacent teeth (n = 90); group B, implants with nonendodontically treated adjacent teeth (n = 123); and group C, implants with endodontically treated adjacent teeth (n = 20). The success and survival rates for implants were both 92.2% in group A, 98.4% and 99.2% for group B, and 85% and 95% for group C, respectively. For adjacent teeth, they were both 99.4% in group B compared with 75% and 90% in group C. However, after case review, none of the implants or adjacent teeth in group B were considered to have E-I or I-E, and one (5%) of the implants in group C had E-I and two (10%) of the adjacent teeth may have had I-E. The results of the present study agree with previous research, which suggests that endodontically treated teeth adjacent to single-tooth implants are usually successful and should be maintained.

STATEMENT OF PROBLEM Despite careful attention to waxing, investing, and casting, marginal discrepancies are inevitable. Vertical and horizontal discrepancies can result in crestal bone resorption, peri-implantitis, and loss of osseointegration. PURPOSE The aim of this study was to evaluate marginal gap and overhang in 3 casting techniques for implant framework fabrication. MATERIALS AND METHODS A total of 24 frameworks, 8 each with the Burn-out Cap (ITI; Straumann) (group BC), with Impression Cap (ITI; Straumann) (group IC), and with conventional wax-up technique (group WX) were fabricated. All specimens were waxed on the analog abutments and cast with Type IV gold alloy. All castings were fixed on the analog abutments with cyanoacrylate and embedded in acrylic resin. Specimens were sectioned and prepared for scanning electron microscope evaluation. Frameworks were analyzed for vertical and horizontal discrepancies with x200 magnification (scanning electron microscopy). Data were analyzed statistically by multivariate analysis and the post hoc tests (alpha = 0.05). RESULTS The vertical discrepancy measurements for the 3 groups showed mean values of 53.74 +/- 11.0 mum, 63.6 +/- 13.2 mum, and 50.1 +/- 17.3 mum, respectively. The interfacial gap differences were not statistically significant in all groups (P > 0.05). Waxing the frameworks with impression caps significantly increased the horizontal discrepancy at the interfaces (P < 0.001). CONCLUSIONS Within the limitations of this experiment, it was demonstrated that the vertical discrepancy of the frameworks made with the 3 techniques were comparable in lack of accuracy with each other. Although conventional waxing produced the least horizontal discrepancy, the difference with burn-out cap group was not statistically different.

One of the major issues confronting the contemporary dental clinician is the treatment decision between extracting a tooth with placement of a dental implant or preserving the natural tooth by root canal treatment. The factors that dictate the correct selection of one procedure over the other for each particular case are not yet established by randomized controlled studies. The aim of this review is to evaluate key factors allowing the clinician to make clinical decisions on the basis of the best evidence and in the patient's best interests. General considerations are discussed that will help the reader analyze clinical studies focused on this problem. Importantly, the major studies published to date indicate that there is no difference in long-term prognosis between single-tooth implants and restored root canal-treated teeth. Therefore, the decision to treat a tooth endodontically or to place a single-tooth implant should be based on other criteria such as prosthetic restorability of the tooth, quality of bone, esthetic demands, cost-benefit ratio, systematic factors, potential for adverse effects, and patient preferences. It can be concluded that endodontic treatment of teeth represents a feasible, practical, and economical way to preserve function in a vast array of cases and that dental implants serve as a good alternative in selected indications in which prognosis is poor.

A technique is presented for the restoration of single-tooth, implant-supported crowns where the abutment and the crown material are chemomechanically bonded; therefore, there is no need for cement, and the implant and implant-abutment are connected with a screwless locking-taper. The clinical and laboratory procedures involved in the fabrication and insertion of the restoration are described in detail. This restoration offers the restorative dentist some advantages: excellent marginal adaptation with a cementless interface, a bacterially sealed implant-abutment connection, a crown material with a similar wear rate and hardness values of human enamel, a simple laboratory technique, and a reduced number of prosthetic components. Due to the light-cured nature of the crown material, chairside modifications can be accomplished. The major drawbacks are: studies are necessary to assess the long-term performance of the Integrated Abutment Crown (IAC)'s in both anterior and posterior areas of the mouth. Resin materials have higher roughness values, accumulate plaque at a higher rate, and are more likely to stain than tooth structure and all-ceramic restorations.

Statement of problem The crown-root ratio guidelines used to establish a prognosis for teeth serving as abutments are commonly applied to a dental implant-supported restoration or potential implant site. These guidelines are generally empirical and therefore lack scientific validation. Purpose The purpose of this study was to first determine the crown-implant ratios of single tooth implant-supported restorations, and then to compare the crown-implant ratios to the guidelines established for the crown-root ratios of natural teeth. Material and methods A retrospective cohort study design was used. The cohort was composed of subjects (n=294) having 1 or more single tooth implants (Bicon) placed between May 1992 and April 2004. A chart review was conducted to obtain radiographs in which the entire crown and implant were visible. The length of the crown and implant were measured directly from the radiographs using magnification to calculate the crown-to-implant ratio. The length of the crown was divided by the length of the implant to determine the crown-implant ratio. Calculations were made to within 0.1 mm. Implant failure was recorded and defined as removal of the implant for any reason. Data were analyzed with descriptive statistics. Results A total of 889 single tooth implants from 294 patients were measured and included in the study. The mean (SD) follow-up time was 2.3 (1.7) years, with a range of 0.1 to 7.4 years. Sixteen failures were recorded for a survival rate of 98.2%. The crown-implant ratios ranged from 0.5:1 to 3:1. The mean (SD) crown-implant ratio of implants in function was 1.3:1 (0.34). The mean crown-to-implant ratio of failed implants was 1.4:1 (2.5). Conclusions The results of this study suggest that the crown-to-root ratio guidelines associated with natural teeth should not be applied to a potential implant site or existing implant restoration. The crown-to-implant ratios of those implants that were in function were similar to those implants that failed.

A single-tooth implant restoration is generally performed for maxillary single-first-molar replacement. If the interdental space between the second premolar and the second molar is large enough, a double-implant placement can be performed to avoid creating mesiodistal cantilever and to distribute occlusal loading forces. If there is not adequate space for a double-implant placement to be performed mesiodistally along the crest of the alveolar ridge line, they should be placed along a diagonal line offset lingually to increase the space. This procedure has two primary advantages. First, greater stability is provided by a double-implant placement. Resistance to lateral forces (palatal-buccal) is much stronger than two implants placed along the alveolar crest ridge line. Residual palatal and buccal bone can provide support against occlusal forces, provided that there is adequate residual bone in these regions. If anatomical conditions are favorable, the placement of two diagonal implants in the palatal and buccal residual bones can be a rational procedure. We report on two typical patients. The progress of these patients was followed using computed tomography for 7 and 6 years, respectively.