Temporary Implants for Patients with Low Bone Density of the Upper Maxilla: An Alternative Rehabilitation Strategy

Background: The use of removable provisional prosthesis after implant placement is undesirable for many patients. In addition, removable prostheses place unfavorable pressure over implants during the healing period. Purpose: The use of temporary implants enable greater stability and functionality of the prostheses. Materials and Methods: This clinical report shows the use of temporary implants in a low density maxilla in conjunction with a fixed provisional prosthesis. Results: The temporary implants contributed to the support of the provisional fixed upper arch prosthesis and to patient comfort with a fixed prosthesis during the healing period. Conclusions: Fixed provisional prostheses are a potentially desirable alternative treatment strategy.     

Treatment of the edentulous atrophic maxilla using zygomatic implants: evaluation of survival rates over 5–10 years

The aim of this retrospective observational cohort study was to analyse and report the 5–10-year survival rates of endosseous zygomatic implants used in the rehabilitation of the atrophic maxilla. Forty-three consecutive zygomatic implant placements in 25 patients were evaluated over a 5–10-year period. All zygomatic implant surgery was carried out under general anaesthesia. Nobel Biocare zygomatic machined-surface implants were used, and placement was undertaken using the modified sinus slot method. The main outcome measures and determinants for success were survival of the restored implants and the proportion of originally planned prostheses delivered to patients. Of the 25 patients treated, 12 were male and 13 were female; 19 were non-smokers, and the mean age at time of surgery was 64 years. Patients were treatment-planned for implant-retained bridgework, a removable prosthesis retained by fixed cast gold or milled titanium beams, or magnet-retained removable prostheses. A combination of zygomatic and conventional implants was used in all but one patient. In this study it was shown that the overall success rate for zygomatic implants was 86%, with six of the implants either failing to integrate or requiring removal due to persistent infection associated with the maxillary sinus. All patients received their planned prosthesis, although in six cases the method of retention required modification. This study illustrates that zygomatic implants are a successful and important treatment option when trying to restore the atrophic maxilla, with the potential to avoid additional augmentation/grafting procedures and resulting in a high long-term success rate.     

A comparative study between currently used methods and Small Volume-Cone Beam Tomography for surgical placement of mini implants

Objective:To compare the outcome of mini implant placement by four different methods: blind placement, a single periapical radiograph (PA), a single panoramic radiograph, and a small-volume cone-beam computed tomography (SV-CBCT). Our hypothesis was that SV-CBCT, with its high resolution, low radiation dose, and three-dimensional depiction of area of interest would yield superior diagnostic information in assessing the potential anchorage site compared to currently used methods that often result in undesired root perforations.Materials and Methods:Potential mini implant sites of 20 dentate or partially dentate human skulls were imaged using three different imaging modalities: PA, panoramic radiograph, and SV-CBCT. Mini implants were placed in 10 maxillary and 10 mandibular randomized sites blindly and using each of the three imaging modalities. Large-volume CBCT scans done postoperatively were used to detect root perforation. Two oral radiologists analyzed the images for perforation of root structures at each site.Results:There was significantly (P < .05) less root perforation with SV-CBCT when compared with other imaging modalities. Fifty-five percent of mini implants placed blindly, 60% of mini implants placed using PA, and 50% of mini implants placed using a panoramic radiograph perforated a root structure, whereas only 5% of mini implants placed using SV-CBCT perforated a root structure.Conclusions:Preoperative evaluation of potential mini implant insertion sites using SV-CBCT aids in predictable placement and results in the least amount of root perforation.     

Mini dental implants for long-term fixed and removable prosthetics: a retrospective analysis of 2514 implants placed over a five-year period

Over the past decade, endosseous implants of increasingly smaller diameters have been introduced into the field of dentistry. Small diameter implants (SDIs) are generally 2.75 mm to 3.3 mm in diameter. They are frequently used in cases of limited alveolar anatomy Mini dental implants (MDIs) are smaller than their SDI counterparts, with diameters ranging from 1.8 mm to 2.4 mm. They are suitable for long-term use-a task for which the device was approved by the Food and Drug Administration. The following study describes the authors' experience with MDIs under this indication. Over a 5-year period, 2514 MDIs were placed in 531 patients. The mean duration of follow-up was 2.9 years. The implants supported fixed (1278) and removable prostheses (1236), with nearly equal placement in the mandible and maxilla (1256 and 1258, respectively). The overall implant survival was 94.2%. Based on a Cox proportional hazards model, statistically significant predictors of failure include use in removable prostheses (hazard ratio = 4.28), the posterior maxilla (3.37), atrophic bone (3.32), and cigarette smokers (2.28). Implant failures (145) were attributed to mobility with or without suppuration (19% vs 81%, respectively). The mean failure time for these implants was approximately 6.4 months (193+/-42 days). This temporally correlates with the osseointegration period. A learning curve was established for this procedure, and implant survival improved with placement experience. Based on these results, the authors have devised treatment guidelines for the use of MDIs in long-term fixed and removable prostheses. MDIs are not a panacea; however, proper training enables the general dentist to successfully implement MDIs into clinical practice.     

Within-subject comparisons of maxillary fixed and removable implant prostheses: Patient satisfaction and choice of prosthesis

Dental implants provide patients with restorative options for the edentulous maxilla. Both fixed and removable prostheses can be attached to the edentulous maxilla, but the efficacy of different designs has not been determined. In this two-session within-subject crossover trial we compared maxillary implant retained fixed prostheses with removable implant overdentures opposed by mandibular implant-supported overdentures. Sixteen patients, who had previously received mandibular implants, entered the study and received four to six maxillary implants. After dropouts as a consequence of a lack of osseointegration and general health problems, 13 remained. Of these, five received the removable prosthesis first and eight the fixed prosthesis. After 2 months, the prostheses were exchanged and the second was also worn for 2 months. Psychometric measurements of general satisfaction with the prostheses as well as comfort, ability to speak, stability, esthetics, ease of cleaning and occlusion were obtained once each prosthesis had been worn for 2 months. Chewing ability was assessed for seven types of food. Removable long-bar overdentures received significantly higher ratings of general satisfaction than fixed prostheses (P = 0.003). Patients also rated their ability to speak and ease of cleaning significantly better with the removable overdentures. Nine patients chose to keep the removable prosthesis and four preferred to keep the fixed prosthesis. The results suggest that maxillary removable overdentures on multiple implants may provide patients with better function than fixed prostheses.     

Artificial intelligence models for tooth-supported fixed and removable prosthodontics: A systematic review

Statement of problemArtificial intelligence applications are increasing in prosthodontics. Still, the current development and performance of artificial intelligence in prosthodontic applications has not yet been systematically documented and analyzed.PurposeThe purpose of this systematic review was to assess the performance of the artificial intelligence models in prosthodontics for tooth shade selection, automation of restoration design, mapping the tooth preparation finishing line, optimizing the manufacturing casting, predicting facial changes in patients with removable prostheses, and designing removable partial dentures.Material and methodsAn electronic systematic review was performed in MEDLINE/PubMed, EMBASE, Web of Science, Cochrane, and Scopus. A manual search was also conducted. Studies with artificial intelligence models were selected based on 6 criteria: tooth shade selection, automated fabrication of dental restorations, mapping the finishing line of tooth preparations, optimizing the manufacturing casting process, predicting facial changes in patients with removable prostheses, and designing removable partial dentures. Two investigators independently evaluated the quality assessment of the studies by applying the Joanna Briggs Institute Critical Appraisal Checklist for Quasi-Experimental Studies (nonrandomized experimental studies). A third investigator was consulted to resolve lack of consensus.ResultsA total of 36 articles were reviewed and classified into 6 groups based on the application of the artificial intelligence model. One article reported on the development of an artificial intelligence model for tooth shade selection, reporting better shade matching than with conventional visual selection; 14 articles reported on the feasibility of automated design of dental restorations using different artificial intelligence models; 1 artificial intelligence model was able to mark the margin line without manual interaction with an average accuracy ranging from 90.6% to 97.4%; 2 investigations developed artificial intelligence algorithms for optimizing the manufacturing casting process, reporting an improvement of the design process, minimizing the porosity on the cast metal, and reducing the overall manufacturing time; 1 study proposed an artificial intelligence model that was able to predict facial changes in patients using removable prostheses; and 17 investigations that developed clinical decision support, expert systems for designing removable partial dentures for clinicians and educational purposes, computer-aided learning with video interactive programs for student learning, and automated removable partial denture design.ConclusionsArtificial intelligence models have shown the potential for providing a reliable diagnostic tool for tooth shade selection, automated restoration design, mapping the preparation finishing line, optimizing the manufacturing casting, predicting facial changes in patients with removable prostheses, and designing removable partial dentures, but they are still in development. Additional studies are needed to further develop and assess their clinical performance.     

Assessing bone's adaptive capacity around dental implants: A literature review

BackgroundIncreased stress (force) on prostheses induces strain (deformation) in the peri-implant bone. Elevated stress and strain could result in the failure of implants that support prostheses. However, the survival rate of implants supporting prostheses under increased stress is high. Either the bone is stronger than expected or it adapts to increased stress. Concepts regarding bone’s adaptive capacity continue to evolve and are the focus of this literature review.Types of Studies ReviewedThe authors searched the literature to find studies that addressed the bone’s capacity to adjust to increased stress and strain. They assessed experimental and clinical trials in which investigators monitored healing after placement of dental implants.ResultsThe data indicate that forces greater than the bone’s adaptive ability can induce loss of osseointegration, as well as osseous resorption. In contrast, it is possible that increased stress on prostheses initiates a reparative process, thereby facilitating retention of implants experiencing increased stress. Numerous lines of evidence support the concept that bone can modify itself to withstand increased mechanical forces.Practical ImplicationsThe authors provide an explanation for the high success rate of prostheses and implants in bone that are exposed to increased stress and strain.     

Management of the edentulous patient

Being edentulous is a handicap, and the main objective of implant placement is to provide support of fixed prostheses or to stabilize complete dentures in the edentulous jaw. Clinical experience and clinical studies have demonstrated the broad application of non-submerged ITI implants in prosthetic therapy in standard sites and in situations of advanced atrophy or substantial loss of tissue. The ITI implant was developed for universal use in partially and completely edentulous patients and for replacement of single missing teeth. The abutment system offers the choice of both removable and fixed prostheses with identical secondary parts. The present article describes the use of ITI implants for prosthodontic rehabilitation in the completely edentulous jaw. Indications and various types of fixed or removable prostheses, alternatives and variations of design are discussed. Prosthetic design is dependent on the number and location of implants, and conversely, the number of implants that can be placed will determine the choice of prosthesis. Treatment planning in general and with respect to individual anatomic-morphologic conditions is described for the upper and lower jaw. Details of clinical procedures with ITI implants related to the specific design of prostheses are presented. Biomechanical aspects of fixation and stabilization of prostheses and aspects of occlusion to be built up complete the overview.     

Influence of implant and conventional prostheses on satisfaction and quality of life: A literature review. Part 2: Qualitative analysis and evaluation of the studies

PURPOSE: To review the influence of prosthodontic and dental implant treatment on patient satisfaction and oral health-related quality of life (OHQOL) based on a systematic search of the literature. MATERIALS AND METHODS: A systematic literature search was carried out for articles published between 1960 and February 2003. Details of the search process and results were reported in Part 1 of the study (Int J Prosthodont2004;17:83-93). The included studies were categorized and evaluated according to their level of evidence, following the guidelines of the Agency for Health Care Policy and Research. The characteristics and content of the studies were analyzed and tabulated. RESULTS: Among the 114 included studies, there were 76 publications reaching evidence level III. The results showed that the effects of compromised oral health are not limited to traditional clinical aspects, but can considerably affect patients in various activities of daily life. Twenty-four of the 38 investigations with evidence levels I and II dealt with implant stabilization of complete mandibular prostheses, comparing implant prostheses to conventional complete dentures. Fully edentulous patients experience negative impacts on OHQOL from their condition. They benefit significantly from the use of dental implants to support mandibular prostheses. However, support by more than 2 implants does not appear to further significantly increase patient satisfaction and OHQOL. CONCLUSIONS: To date, research in the field of patient-based outcomes has concentrated on dental implant treatment for the edentulous patient. Other prosthetic treatments such as single crowns, fixed and removable partial dentures, or further treatment concepts (eg, the shortened dental arch concept) are not well represented. The use of patient-centered outcome measures can help to find an individual, patient-oriented prosthetic solution.     

Implant loss and crestal bone loss in immediate versus delayed load in edentulous mandibles: A systematic review and meta-analysis

Statement of problemThe current trend is to shorten the loading times of dental implants. However, information about the risk of early loss of implants that have been loaded immediately is scant if compared with data available for those conventionally loaded.PurposeThe purpose of this systematic review and meta-analysis was to study immediate (IL) and delayed loading (DL) protocols in edentulous mandibles to determine whether differences exist in implant success and crestal bone loss and to evaluate these possible differences in relation to the type of prosthesis and the splinting of the implants.Material and methodsThe literature review was conducted in PubMed, Scopus, and the Cochrane Library. Nine randomized clinical trials were included.ResultsThe result of a meta-analysis of implant loss before 1 year was 2.63 (95% CI: 1.22, 5.68), favoring the DL control group, while the outcome for crestal bone loss at the observation year was 0.42 (95% CI: -0.35, 1.20), with a tendency toward reduced bone loss for DL.ConclusionsThe risk of early loss in the IL group was higher than that in the DL group. For removable prostheses and nonsplinted implants, DL was preferred. The quality of scientific evidence significantly favors DL.     

Influence of surface treatment by laser irradiation on bacterial adhesion on surfaces of titanium implants and their alloys: Systematic review

ObjectiveThe aim of this systematic review was to present the current knowledge on the influence of laser surface treatment on the adhesion of bacteria to titanium and its alloys.DesignThis review was structured according to PRISMA guidelines for systematic reviews and meta-analyses, and registered on the Open Science Framework platform (https://doi.org/10.17605/OSF.IO/FTA3W). Article searches were performed in 4 databases: PubMed, Scopus, Embase, and Science Direct. In addition, a manual search was performed in the reference lists of the selected articles. The selection of articles was performed by two reviewers. The articles found were screened for eligibility using the previously established inclusion and exclusion criteria. The methodological quality of the studies was assessed using the Joanna Briggs Institute (JBI) Critical Assessment Checklist for Quasi-Experimental Studies (non-randomized experimental studies).ResultsMost of the studies evaluated showed that surface treatment by laser irradiation can affect the adhesion of bacteria to titanium surfaces and that this is directly related to changes in surface properties such as chemical composition, morphology, roughness, and wettability, as well as the type of bacterial species involved.ConclusionsThe studies considered in this systematic review have shown that surface treatment by laser irradiation is a promising technique to reduce the adhesion of bacteria on the surface of titanium implants.     

Mechanical Self-performed Oral Hygiene of Implant Supported Restorations: A Systematic Review

A systematic review of self-performed oral hygiene practices for optimal maintenance of dental implant-supported restorations reveals a lack of evidence to support best practices.BackgroundThe standard of the patients' home care is a key factor for long term stability of dental implants and the prevention of biological complications. The objective of this systematic review is to evaluate and summarize the literature with respect to various mechanical oral hygiene modalities around implant-supported restorations.MethodsMEDLINE, Cochrane-CENTRAL and EMBASE databases were searched up to October 2013 to identify eligible studies. Five studies that met the inclusion criteria were included. Two cohort studies about powered toothbrushes and three (randomized) controlled trials comparing powered to manual toothbrushes were reviewed. All studies showed an improvement in the clinical parameters over time. Powered toothbrushes were found to perform better than manual toothbrushes but no firm conclusions can be made between treatment modalities.ConclusionsThere is a lack of evidence with respect to effective and optimal self-performed oral hygiene around dental implants. At present, home care recommendations are based on the knowledge that is available with respect to cleaning of natural teeth. It becomes evident that there is an urgent need for academic institutions and industry to initiate and support high quality randomized controlled clinical trials on this topic in the near future.     

Tilted Implants for the Rehabilitation of Edentulous Jaws: A Systematic Review

Purpose: The aim of this review was to evaluate the survival rate of upright and tilted implants supporting fixed prosthetic reconstructions for the immediate rehabilitation of partially and fully edentulous jaws, after at least 1 year of function. Materials and Methods: An electronic search of databases plus a hand search on the most relevant journals up to December 2009 was performed. The articles were selected using specific inclusion criteria, independent of the study design. Results: The literature search yielded 347 articles. A first screening based on the title and abstract identified 25 eligible studies. After full‐text review of these studies, 10 articles were selected for analysis. Seven were prospective single‐cohort studies and three had a retrospective design. A total of 462 patients have been rehabilitated with 470 immediately loaded prostheses (257 in the maxilla, 213 in the mandible), supported by a total of 1,992 implants (1,026 upright and 966 tilted). Twenty‐five implants (1.25%) failed in 20 patients within the first year. All failures except one occurred in the maxilla. No significant difference in failure rate was found between tilted and upright implants, nor between maxillary and mandibular implants. No prosthesis failure was reported. Limited peri‐implant bone loss was reported with no difference between upright and tilted implants. Full patients' satisfaction for function, phonetics, and esthetics was reported in three studies, based on questionnaires. Conclusions: The use of tilted implants to support immediately loaded fixed prostheses for the rehabilitation of edentulous jaws can be considered a predictable technique, with an excellent prognosis in the short‐medium term. However, randomized long‐term trials are needed to determine the efficacy of this surgical approach.     

The Marius implant bridge: surgical and prosthetic rehabilitation for the completely edentulous upper jaw with moderate to severe resorption: a 5-year retrospective clinical study

Background: Patients seeking replacement of their upper denture with an implant‐supported restoration are most interested in a fixed restoration. Accompanying the loss of supporting alveolar structure due to resorption is the necessity for lip support, often provided by a denture flange. Attempts to provide a fixed restoration can result in compromises to oral hygiene based on designs with ridge laps. An alternative has been an overdenture prosthesis, which provides lip support but has extensions on to the palate and considerations of patient acceptance. The Marius bridge was developed as a fixed bridge alternative offering lip support that is removable by the patient for hygiene purposes, with no palatal extension beyond normal crown‐alveolar contours. Purpose: Implant‐supported restorative treatment of completely edentulous upper jaws, as an alternative to a complete denture, is frequently an elective preference, and it requires significant patient acceptance beyond the functional improvement of chewing. Patients with moderate to severe bone resorption and thin ridges present additional challenges for adequate bone volume and soft‐tissue contours. The purpose of this investigation was to develop a surgical and prosthetic implant treatment protocol for completely edentulous maxillae in which optimal lip support and phonetics is achieved in combination with substantial implant anchorage without bone grafting. Materials and Methods: The Marius bridge is a complete‐arch, double‐structure prosthesis for maxillae that is removable by the patient for oral hygiene. The first 45 consecutive patients treated by one person (YF) in one center with this concept are reported, with 245 implants followed for up to 5 years after prostheses connection. Results: The cumulative fixture survival rate for this 5‐year retrospective clinical study was 97%. Five fixtures failed before loading, in five different patients, and two fixtures in the same patient failed at the 3‐year follow‐up visit. None of the bridges failed, giving a prostheses survival rate of 100%. The complications were few and mainly prosthetic: nine incidences of attachment component complications, one mesobar fracture, and three reports of gingivitis. All complications were solved or repaired immediately, with minimal or no interruption of prostheses use. Conclusions: Satisfactory medium‐term results of survival and patient satisfaction show that the Marius bridge can be recommended for implant dentistry. The technique may reduce the need for grafting, because it allows for longer implants to be placed with improved bone anchorage and prostheses support.     

Number of implants for mandibular implant overdentures: a systematic review

PURPOSE

The aim of this systematic review is to address treatment outcomes of Mandibular implant overdentures relative to implant survival rate, maintenance and complications, and patient satisfaction.

MATERIALS AND METHODS

A systematic literature search was conducted by a PubMed search strategy and hand-searching of relevant journals from included studies. Randomized Clinical Trials (RCT) and comparative clinical trial studies on mandibular implant overdentures until August, 2010 were selected. Eleven studies from 1098 studies were finally selected and data were analyzed relative to number of implants.

RESULTS

Six studies presented the data of the implant survival rate which ranged from 95% to 100% for 2 and 4 implant group and from 81.8% to 96.1% for 1 and 2 implant group. One study, which statistically compared implant survival rate showed no significant differences relative to the number of implants. The most common type of prosthetic maintenance and complications were replacement or reattaching of loose clips for 2 and 4 implant group, and denture repair due to the fracture around an implant for 1 and 2 implant groups. Most studies showed no significant differences in the rate of prosthetic maintenance and complication, and patient satisfaction regardless the number of implants.

CONCLUSION

The implant survival rate of mandibular overdentures is high regardless of the number of implants. Denture maintenance is likely not inflenced substantially by the number of implants and patient satisfaction is typically high again regardless os the number of implants.     

Effect of local zoledronate delivery on osseointegration: a systematic review of preclinical studies

Purpose: The aim of the present systematic review was to assess the effect of local zoledronate (ZOL) delivery (topical or as implant surface coatings) on osseointegration.

Materials and methods: In this systematic review, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. To address the focused question, ‘Does local zoledronate delivery enhance osseointegration?’ indexed databases were searched without time or language restrictions up to and including April 2017 using various combination of the following keywords: ‘zoledronate’, ‘bisphosphonates’, ‘osseointegration’ and ‘topical administration’. Letters to the Editor, historic reviews, commentaries, case-series and case-reports were excluded.

Results: Initially, 383 articles were identified out of which, 23 experimental studies fulfilled the inclusion criteria. In 18 studies, ZOL was incorporated into implants surfaces as a coating and in five studies ZOL was applied topically (bone graft or irrigation) into the bone cavities. Results from 87% studies reported that local delivery of ZOL (coating or topical) is effective in enhancing osseointegration or new bone formation around implants.

Conclusions: Local ZOL delivery (coating or topical) seems to enhance osseointegration in animals; however, from a clinical perspective, further randomized control trials with long-term follow-up are needed in this regard.     

Level of satisfaction in patients with maxillary full-arch fixed prostheses: zygomatic versus conventional implants

PURPOSE: To evaluate the satisfaction of patients with maxillary fixed prostheses supported by conventional and/or zygomatic implants. MATERIALS AND METHODS: Patients restored with complete maxillary implant-supported fixed prostheses were included in the study. They were divided into 2 groups: those with at least 1 zygomatic implant (the zygomatic group) and those with no zygomatic implants (the nonzygomatic group). Twelve months after prosthesis delivery, subjects indicated their satisfaction with the new prosthesis on a visual analog scale. Prostheses were rated in terms of general satisfaction, comfort and stability, ability to speak, easy of cleaning, esthetics, self-esteem, and functionality. RESULTS: Forty-six patients participated in the study (23 in each group). The mean level of satisfaction was high; the groups differed significantly only in satisfaction with esthetics. Patients in the zygomatic group had a higher average score for esthetics than those in the nonzygomatic group. Those who had previously worn conventional removable prostheses gave a higher score for functionality to the implant-supported fixed prosthesis compared to the removable prosthesis. CONCLUSION: Patient satisfaction with zygomatic implant-supported fixed prostheses was similar to that for fixed prostheses supported by conventional implants.     

Immediate Obturator Stabilization Using Mini Dental Implants

Edentulous patients with maxillary defects face a more challenging oral rehabilitation process than dentate patients. With the use of mini dental implants (MDIs), it is now possible to immediately increase obturator retention and stability. Implant patients can have a retentive obturator that enhances the overall efficacy of the prosthesis both in comfort and function.     

A comparison of hydroxylapatite coated implant retained fixed and removable mandibular prostheses over 4 to 6 years

In a 6-year prospective clinical study, 181 hydroxylapatite coated endosseous dental implants were placed into the anterior mandible of 48 patients. Twenty-one patients were treated with fixed prostheses and 27 patients with an overdenture. When the implants were exposed all 181 had integrated. To date, there is 100% survival of all implants and they all retain a functioning prostheses. The initial results were very promising, in both groups the interval success was over 95% in the first 4 years of the study. However, by year 6, the interval success rates had fallen to 83% for both the fixed and removable groups. This study also compares the construction and maintenance complications for the two types of restorations. The clinical time taken, after implant exposure, to construct the prostheses was similar whether the fixed (mean of 8 visits) or removable option (mean of 7 visits) was chosen. However, the removable restoration cost less than half the price of the fixed when both technical time and implant component costs were evaluated. Maintenance for both groups was higher than expected, but patients required more appointments in the removable group both in the first year and beyond. Regarding the prostheses itself, the incidence of remakes, relines and general adjustments was higher in the removable group. This study has shown that the overdenture offers an effective and initially a more economical alternative to the fixed prostheses, in the treatment of the edentulous mandible. However, long-term maintenance of such a prosthesis can be significant.