A 10-Year Prospective Study of Single Tooth Implants Placed in the Anterior Maxilla

Eleven- to fifteen-year outcome for two-piece implants with an internal tube-in-tube connection: a cross-sectional analysis of 245 implants

PURPOSE

The aim of this retrospective study was to evaluate the outcomes of a two-piece implant system with a tube-in-tube internal connection after up to 15 years of clinical use.

MATERIAL AND METHODS

A retrospective follow-up examination of patients treated with internal tube-in-tube implants between 2003 and 2006 was conducted. The implant survival rates, peri-implant conditions (marginal bone loss, bleeding on probing, plaque index, probing depth), and technical complications were determined.

RESULTS

In total, 312 dental implants were placed in 152 patients. Of the original 152 patients enrolled, 245 implants in 112 patients were available for a follow-up evaluation after 11 to 15 years (mean observation time, 12.9 ± 1.1 years). The overall implant survival rate was 93.9%. Outcomes for MBL (1.49 ± 1.23 mm), PI (24.3 ± 22.2%), BOP (18.3 ± 28.7%), and PD (2.74 ± 1.21 mm) were observed. Selected parameters (time after implant surgery, smoking habits, bone augmentation (GBR)) showed an influence on MBL and PD.

CONCLUSIONS

The internal tube-in-tube implant system showed favorable long-term results. The correlation of MBL and PD with the patient-specific factor smoking habit is in accordance with other studies.

CLINICAL RELEVANCE

Camlog Root-Line implants with a tube-in-tube implant-abutment connection and a 1.6-mm polished neck configuration have demonstrated favorable long-term outcomes in daily clinical practice. However, it is important to note that these implants are no longer available on the market.

Clinical and radiographic outcomes of a combined surgery approach to treat peri-implantitis

Peri-implant infra-bony defects are difficult to treat, and data on the management of peri-implantitis are lacking. The aim of this study was to evaluate the effect of a combined surgical approach to manage peri-implantitis: implantoplasty with xenogeneic bone grafting and a concentrated growth factor membrane. Two independent examiners analysed the medical records and radiographs taken before surgery and at the last follow-up. Data were analysed at the implant level; some patient-level data (age, sex, smoking habit) were also considered. Linear regression analysis with generalized estimating equations (GEE) was used to explore the effect of variables of interest (including marginal bone level (MBL)) on implantitis treatment success and resolution rates. The effect of the prosthesis type on postoperative clinical and radiographic parameters was also explored by GEE, with adjustment for age, sex, tooth site, location, follow-up duration, and implant length (model IV including all). Thirty patients with 72 implants were investigated. The implant survival rate was 100% over a mean observation period of 3.3 years (range 2-11 years). The treatment success rate (bone loss <0.5 mm, no bleeding on probing (BOP), no suppuration, probing depth (PD) < 5 mm) was higher in females than males (50% vs 19.0%; P = 0.008). At the last postoperative follow-up, the MBL (1.51 ± 1.07 vs 4.01 ± 1.13 mm), PD (3.61 ± 0.84 vs 6.54 ± 1.01 mm), and BOP (23.38 ± 23.18% vs 79.17 ± 15.51%) were significantly reduced when compared to pre-surgery values (all P < 0.001). Furthermore, a significantly higher PD reduction (β = -1.10 mm, 95% confidence interval -1.97 to -0.23 mm, P = 0.014) was observed for implants with a single crown than a full-arch prosthesis (GEE model IV). Preliminary clinical and radiographic data indicate that implantoplasty in combination with surgery could be an effective treatment option for peri-implantitis.

Immediate Loading Using the Digitalized Customized Restoration of Single-tooth Implants Placed in Fresh Extraction Sockets in the Aesthetic Anterior Maxilla: A 10-Year Prospective Study of Marginal Bone Level

AIM

The objective of this study was to assess marginal bone level around single implants inserted in fresh extraction sockets in the anterior maxillary region and instantly restored with computer-aided design/computer-aided manufacturing customized temporary crowns cemented on the final abutment.

MATERIALS AND METHODS

A total of 20 patients (15 females and 5 males, with a mean age of 30 years), where 20 were placed in fresh extraction sockets. After raising a full-thickness flap, atraumatic extraction was performed the implant site was prepared and fixtures were stabilized on the palatal bone wall. The implant location was immediately transmitted to the prepared master model using the pick-up impression coping seated in the surgical guide template. Prefabricated abutments were used as the final abutment on the master model, scanned and the crown was planned using computer-aided manufacturing customized software. Later on 8th weeks, abutments were torqued as per the manufacturer's recommendation, and the final crowns were cemented. Using personalized intraoral radiographs marginal bone level was evaluated mesially and distally to the implant shoulder as a reference at implant placement, 8 weeks, 1, 3, 5, and 10 years after loading.

RESULTS

Wholly implants were osteo-integrated positively after 10 years of practical loading, but only 18 were available for clinical and radiological follow-up, and 2 patients with two implants were excluded from the study due to relocation abroad without any implant failure. The average marginal bone loss (MBL) in the current report was 0.16 ± 0.167 mm at crown cementation, 0.275 ± 0.171 mm after 1 year, 0.265 ± 0.171 mm after 3 years, 0.213 ± 0.185 mm after 5 years, and 0.217 ± 0.194 mm at 10 years.

CONCLUSION

The strategy of inserting and not removing the final abutment at the time of implant placement facilitates the establishment of adequate attachment of both soft and hard tissues to the abutment surface, ensuring uninterrupted organization of tissue architecture and offers advantages in helping maintain soft tissue maturation and preventing marginal bone level.

CLINICAL SIGNIFICANCE

Immediately loaded implants in freshly extracted sockets lead to a significant reduction in marginal ridge resorption. The use of a temporary crown on a prefabricated abutment, exclusive of successive abutment manipulation, proved effective in preserving the primarily founding blood clot and served as a prototype for shaping the soft tissue around the previously wounded gum. How to cite this article: Berberi A, El Zoghbi A, Aad G, et al. Immediate Loading Using the Digitalized Customized Restoration of Single-tooth Implants Placed in Fresh Extraction Sockets in the Aesthetic Anterior Maxilla: A 10-Year Prospective Study of Marginal Bone Level. J Contemp Dent Pract 2024;25(3):213-220.

Clinical study with sandblasted dental implants: a 17-year retrospective follow up

Sandblasting is a standard procedure used for treating dental implant (DI) surfaces to enhance the osseointegration with known clinical success. This clinical study aimed to evaluate the long-term clinical outcomes of DIs with external hexagon connections and a surface sandblasted with calcium phosphate. Two hundred and seventy-five Mg-osseous™ (Mozo-Grau™) screw DIs were placed in 86 patients using a two-stage surgical technique and conventional loading protocol (at three months). Dental implants and prosthetic clinical findings were evaluated during a 17-year follow up. Four DIs were lost during the healing period, and 108 prostheses were placed over the 271 DIs left: 58 unitary implant-supported prosthesis (ISP), 31 partially ISP, 14 full-arch ISP, and five overdentures. Fourteen DIs were lost during the follow-up period. Clinical results indicated a DI survival rate of 93.50%. A total of 11.80% of DIs showed peri-implantitis as the primary biological complication. The mean (SD) marginal bone loss was 1.78 (0.40) mm, ranging from 0.90 to 2.80 mm. The most frequent complication was mechanical prosthodontic complications (24.40%). Sandblasted surface DIs inserted in both maxillary and mandibular areas produce favourable long-term (17-year follow up) outcomes and stable tissue conditions when a delayed loading protocol is followed.

Two adjacent implant-supported restorations in the aesthetic region: A 10-year prospective case series

INTRODUCTION

The treatment outcome of two adjacent implant-supported restorations in the maxillary aesthetic region was assessed regarding peri-implant soft and hard tissues, and satisfaction during a 10-year follow-up period.

METHODS

Twenty patients missing two adjacent teeth in the maxillary aesthetic region and treated with two implant-supported restorations were followed prospectively. The patients' clinical and radiographic parameters, as well as their satisfaction, were scored for a 10-year follow-up period.

RESULTS

Seventeen patients' data were available for the 10-year follow-up. The survival rate of the implants and restorations was 100%. The 10-year mean peri-implant bone change at the side facing the adjacent tooth was +0.11 ± 0.57 mm and at the side facing the adjacent implant was -0.08 ± 0.50 mm. The peri-implant soft tissues were healthy and the patients' satisfaction was high, but the papilla-index showed compromised inter-implant papillae and low Pink Esthetic Scores. These figures were of the same magnitude at all time points.

CONCLUSION

While it is difficult to obtain sufficient inter-implant papillae and satisfactory Pink Esthetic Scores, the initial treatment results remained stable and the patients were satisfied with the final result throughout the 10-year follow-up period.

Survival and complication rates of two dental implant systems supporting fixed restorations: 10-year data of a randomized controlled clinical study

OBJECTIVES

To compare clinical, radiographic, biological and technical long-term outcomes of two types of dental implants over a period of 10 years.

MATERIALS AND METHODS

Ninety-eight implants were placed in 64 patients, randomly allocated to one of two manufacturers (AST and STM). All implants were loaded with fixed restorations. Outcome measures were assessed at implant insertion (Ti), at baseline examination (TL), at 1, 3, 5, 8 and 10 (T10) years. Data analysis included survival, bone level changes, complications and clinical measures.

RESULTS

Re-examination was performed in 43 patients (23 AST and 20 STM) at 10 years. The implant level analysis was based on 37 (AST) and 32 (STM) implants. Survival rates of 100% were obtained for both groups. The median changes of the marginal bone levels between baseline and T10 (the primary endpoint) amounted to a loss of 0.07 mm for group AST and a gain of 0.37 mm for group STM (intergroup p = 0.008). Technical complications occurred in 27.0% of the implants in group AST and in 15.6% in group STM. The prevalence of peri-implant mucositis was 29.7% (AST) and 50.1% (STM). The prevalence of peri-implantitis amounted to 0% (AST) and 6.3% (STM).

CONCLUSIONS

Irrespective of the implant system used, the survival rates after 10 years were high. Minimal bone level changes were observed, statistically significant but clinically negligible in favor of STM. Technical complications were more frequently encountered in group AST, while group STM had a higher prevalence of peri-implant mucositis.

Corrosion Resistance and Titanium Ion Release of Hybrid Dental Implants

One of the strategies for the fight against peri-implantitis is the fabrication of titanium dental implants with the part close to the neck without roughness. It is well known that roughness favors osseointegration but hinders the formation of biofilm. Implants with this type of structure are called hybrid dental implants, which sacrifice better coronal osseointegration for a smooth surface that hinders bacterial colonization. In this contribution, we have studied the corrosion resistance and the release of titanium ions to the medium of smooth (L), hybrid (H), and rough (R) dental implants. All implants were identical in design. Roughness was determined with an optical interferometer and residual stresses were determined for each surface by X-ray diffraction using the Bragg-Bentano technique. Corrosion studies were carried out with a Voltalab PGZ301 potentiostat, using Hank's solution as an electrolyte at a temperature of 37 °C. Open-circuit potentials (Eocp), corrosion potential (Ecorr), and current density (icorr) were determined. Implant surfaces were observed by JEOL 5410 scanning electron microscopy. Finally, for each of the different dental implants, the release of ions into Hank's solution at 37 °C at 1, 7, 14, and 30 days of immersion was determined by ICP-MS. The results, as expected, show a higher roughness of R with respect to L and compressive residual stresses of -201.2 MPa and -20.2 MPa, respectively. These differences in residual stresses create a potential difference in the H implant corresponding to Eocp of -186.4 mV higher than for the L and R of -200.9 and -192.2 mV, respectively. The corrosion potentials and current intensity are also higher for the H implants (-223 mV and 0.069 μA/mm²) with respect to the L (-280 mV and 0.014 μA/mm² and R (-273 mV and 0.019 μA/mm²). Scanning electron microscopy revealed pitting in the interface zone of the H implants and no pitting in the L and R dental implants. The titanium ion release values to the medium are higher in the R implants due to their higher specific surface area compared to the H and L implants. The maximum values obtained are low, not exceeding 6 ppb in 30 days.

Quantitative parameters of digital occlusal analysis in dental implant supported restorative reconstruction recent 5 years: a systematic review

OBJECTIVE

The aims of this systematic review were to evaluate the clinical masticatory performance of implant-supported restorations, observe the occlusal force changes in the distribution of the implant restoration and reveal the positive and negative contributing factors of implant design and components based on the outcomes of digital occlusal measurement.

MATERIAL AND METHODS

An extensive search was conducted through PubMed and CENTRAL to identify clinical trials on implant-retained restorations using digital occlusal analysis methods. Two researchers assessed the identified studies and data extraction independently, and the data synthesis strategies without meta-analysis that summarizes the effect estimates were adopted.

RESULTS

The search screened 3821 titles and abstracts, then full-text analysis for 26 articles was performed, and 14 studies were included in the quantitative synthesis. Four of six studies for implant-retained overdenture showed statistically significant improved bite force when immediate loading (p = .00045, .00005, .00055, and .00005, respectively), and no statistically significant results in the other two studies (p = .225, .371, respectively.) However, the results of the favoured intervention were not statistically significant (p = .104, .166, respectively) in two studies of single posterior implant restorations. In all three studies, the bite force distributed on the implant prostheses of partially fixed implant-retained restoration increased statistically significantly (p = .013, .001, .05, respectively).

CONCLUSIONS

The edentulous restoration supported by implants seems to significantly improves bite force and chewing efficiency compared with conventional dentures. Regular quantitative occlusal measurement is recommended to avoid the possible risk of overload. Smaller implants size and relatively small and flexible attachment designs may be more conducive to the stability and retention of the restoration of atrophy of alveolar bone.

Clinical performance of different types of dental prosthesis in patients with head and neck tumors-a retrospective cohort study

OBJECTIVES

To investigate how different types of dental prosthesis perform in patients with head and neck tumors.

MATERIALS AND METHODS

In this retrospective clinical cohort study, the impact of different patient-related factors was analyzed as influencing factors on the survival probability of dental prosthesis using Kaplan-Meier estimate. For analysis, the dental prosthesis was divided into groups: group 1 (fixed dental prosthesis), group 2 (removable dental prosthesis), group 3 (implant-supported dental prosthesis), and group 4 (prostheses anchored using wrought wire clasps and obturators). The incidental aftercare measures were also evaluated.

RESULTS

Two hundred seventy-nine restorations were observed (mean observation: 2.7 ± 3.0 years, max.14.8 years) out of which 49 (17.6%) had to be replaced during the observation. After 5 years, 100% of group 1 restorations, 79.9% of group 2 restorations, 91.4% of group 3 restorations, and 30% of group 4 restorations were still functional. Four hundred eighty-eight dental implants were observed, of which 77 (15.8%) failed.

CONCLUSIONS

Groups 1, 2, and 3 restorations showed good survival times after 5 years in function, whereas group 4 presented the worst survival times. Group 2 restorations showed the highest amount of necessary aftercare measures.

CLINICAL RELEVANCE

The current investigation shows that groups 1, 2, and 3 restorations should be preferred in the prosthetic treatment planning of patients with head and neck tumors. A treatment with group 4 restorations should only be considered if no other prosthetic treatment is possible or as temporary treatment.

Effect Morphology and Surface Treatment of the Abutments of Dental Implants on the Dimension and Health of Peri-Implant Biological Space

Statement of the problem: The gingival configuration around implant abutments is of paramount importance for preserving the underlying marginal bone, and hence for the long-term success of dental implants. Objective: The objective was to study, clinically and histologically, the effects of the change in the morphology of abutments connected to the endosseous implant, and of their surface treatment. In particular, the objective was to ascertain the effect of changing the shape of the transepithelial pillar and the treatment of its surface on the dimensions, quality and health of the components of the peri-implant biological space, such as the dimensions of the epithelial and connective tissues of the biological space, the concentration of inflammatory cells and the density of collagen fibers. Methods: A clinical trial of 10 patients with a totally edentulous maxilla, who had four implants (IPX4010_GALIMPLANT®, Sarria, Spain) inserted in the area of the first and second molars on both sides with computer-guided implant surgery, was conducted with the final purpose of assessing the quality of the peri-implant soft tissue attachment around the transepithelial abutments which were employed (aesthetic machined (RM), aesthetic anodized (RA), slim machined (SM) and slim anodized (SA)). At 8 weeks and following the collection of the samples (removal of the implant-abutment assembly with its surrounding hard and soft tissue) and their processing for subsequent histological and histomorphometric analysis in order to study the dimensions, quality and health of the peri-implant soft tissue area, the variables previously mentioned were determined according to the aims of the study. By using appropriate diameter trephine in order to obtain a useful fringe of soft tissue around the transepithelial pillars, ANOVA and chi-square tests were performed. Results: The SPSS statistical analysis ANOVA results revealed that the machined slim abutments have a better performance considering the variables analyzed with epithelial and connective attachment heights of 1.52 mm and 2.3 mm, respectively, and that connective density (density of collagen fibers) was high at 85.7% of the sample size affected by the design for the slim abutments and 92.9% of the high-density sample size affected by the surface treatment for the machined surface. Conclusions: All variables studied, despite the small sample size, showed the superiority of the slim machined abutment among the four groups.

Randomized controlled clinical study comparing two types of two‐piece dental implants supporting fixed restorations – results at 8 years of loading

Objectives

To assess clinical, technical, biological, and radiographic outcomes of implants supporting fixed restorations using two types of dental implants with non‐matching implant–abutment junctions at 8 years.

Materials and methods

Sixty‐four patients were randomly assigned to receive one of two implant systems (S1 or S2) and eventually fixed restorations. Patients were examined at loading (T_L), one (T₁), three (T₃), five (T₅), and eight years (T₈). Outcome measures included implant and restoration survival, technical and biological complications, and radiographic bone levels. All data were analyzed on the implant and patient level.

Results

Ninety‐eight implants were inserted in 64 patients and loaded with fixed restorations. At 8 years, 49 patients with 42 (S1) and 36 (S2) implants (25 in group S1 and 24 in group S2 on the patient level) were re‐examined. The survival rates on the patient level were 97.6% (S1) and 97.2% (S2). The marginal bone levels (the primary endpoint) amounted to a gain of 0.21 mm (Q1: −0.11 mm; Q3: 0.5 mm) (S1) (p = .007) and to a loss of 0.24 mm (Q1: −0.79 mm; Q3: 0.05 mm) (S2) (p = .001) between baseline (T_L) and T₈ (intergroup p < .001). The technical complication rates were 28% (S1) and 12.5% (S2) (intergroup p = .289). Peri‐implant mucositis was observed in 24% (S1) and 50% (S2) of the implants on the patient level (intergroup p = .792). The respective figures for peri‐implantitis were 0% (S1) and 12.5% (S2) (intergroup p = .11).

Conclusions

Dental implants with non‐matching implant–abutment junctions supporting fixed restorations resulted in high survival rates independent of the system used. Differences, mainly observed in terms of technical complications (in favor of S2), biological complications (in favor of S1), and marginal bone‐level changes (in favor of group S1), appear to be clinically negligible.

Implant treatment after traumatic tooth loss: A systematic review

BACKGROUND/AIMS

Treatment after traumatic tooth loss is challenging and is currently guided by expert opinion and the individual patient situation. The aim of this study was to provide an overview on the outcome of dental implant treatment in the anterior maxilla after traumatic tooth loss, based on a systematic review of the existing evidence.

MATERIALS AND METHODS

A systematic search of the literature was performed on PubMed, Cochran Library and Web of Science following the PRISMA guidelines based on a structured research question (PICO). All clinical studies of five patients or more with follow-up of at least 1 year after implant loading were included. Patients were at least 18 years of age. Cohen's Kappa-coefficient was calculated. The Newcastle-Ottawa Scale was applied to assess the quality of the included studies. Descriptive statistical methods were applied.

RESULTS

Nine hundred and ninety-nine articles were identified through the systematic search. Finally, six articles were eligible for inclusion. The studies comprised prospective and retrospective cohort studies and case series. From these, 96 patients with 120 implants were included. The age ranged from 18 to 59 years. The survival rates of implants and superstructures were 97% and 95%, respectively, after a mean follow-up of 3.5 years. Mean marginal bone resorption was 0.56 mm (range 0.21-1.30 mm). Complication rates were 7% and 11% on implant and superstructure level, respectively. Patient-reported outcome measures and objective evaluations showed a high level of satisfaction with the aesthetic outcome. Bone augmentation was performed in 60 implant sites. Three patients underwent pre-surgical orthodontic treatment. The maxillary central incisor was the most frequently replaced tooth (70%).

CONCLUSIONS

This systematic review revealed a low level of evidence on the outcome of dental implant treatment after traumatic tooth loss. Systematic reporting of treatment outcomes of tooth replacements after dental trauma is highly encouraged to further guide dentists for the benefit of these challenging patients.

Osseoperception following dental implant treatment: a systematic review

OBJECTIVES

Osseoperception is defined as the ability to perceive tactile sensation via mechanoreception in the peri-implant environment. The objective was to systematically review the available literature on the osseoperception phenomenon following dental implant placement and to explore potential factors which might improve the perception capacity.

MATERIAL AND METHODS

A literature search was performed using PubMed, Cochrane, Embase, and Web of Science databases up to June 2021. Both human and animal studies assessing sensory capacity or innervation following implant placement were included in this review. Two reviewers independently performed the study selection, data extraction and quality assessment of the included studies. The methodological quality of the included papers was assessed using Cochrane risk of bias for human studies and SYRCLE's risk of bias tool for animal studies.

RESULTS

The electronic search of databases yielded 1667 results. Following removal of duplicates, title and abstract screening and full-text reading, 22 publications were eligible to be included in the review. Psychophysical evidence from 14 studies indicated a lower tactile function of implants, where active and passive threshold level were found to be 5 and 50 times higher for implants compared to natural teeth, respectively. The neurophysiological evidence from 3 studies indicated cortical plasticity following dental implant placement, measured via trigeminal nerve evoked potentials and functional magnetic resonance imaging. Histological evidence from 5 studies demonstrated the presence of myelinated nerve fibres in the peri-implant tissues. Additionally, immediate implant placement and loading showed beneficial effect on peri-implant tissue (re)innervation, however, no other biological or physiological factors could be identified influencing osseoperception.

CONCLUSIONS

The reported evidence supported the existence of so-called osseoperception phenomenon for restoring the sensory feedback pathway following oral implant rehabilitation. Further studies are required to identify factors that might further assist physiological integration of the oral implants in the human body as such to approach natural oral function.

Patient's perception of timing concepts in implant dentistry: A systematic review

Protocols for implant dentistry, most frequently include periods until healing of the extraction sockets and osseointegration of the implant. Deductional thinking imply that patients would prefer if treatment time in implant dentistry were reduced.

AIM

What is the patient perception of immediate or early implant placement or loading in comparison with traditional, delayed placement, and/or loading assessed by patient-reported outcome measures, as evidenced in randomized controlled clinical trials or prospective controlled studies?

MATERIAL AND METHODS

A systematic review was performed following the PRISMA guidelines with a literature search up to June 30. All hits were imported into Rayyan online software and analyzed by two authors for eligibility. Cochrane RoB2.0 and Newcastle-Ottawa Scale were used to evaluate risk of bias in the individual studies.

RESULTS

Of the initially 1439 articles, 76 underwent full-text analysis and finally 40 articles, representing 35 cohort studies, were included. The quality evaluation demonstrated some concerns among most of the studies.

CONCLUSION

a) There is no strong evidence to support that the time for implant placement or loading of implant-supported single or short-span reconstructions or overdentures influence patients´ discomfort, satisfaction with function or esthetics or overall satisfaction with the implant treatment. b) There is some evidence that studies including edentulous patients rehabilitated with implant-supported full-arch FDPs demonstrate more satisfied patients with immediate than for the early or delayed loaded implant reconstructions after short time, but the difference is not clear one year after treatment.

Long-term outcomes of maxillary single-tooth implants in relation to timing protocols of implant placement and loading: Systematic review and meta-analysis

OBJECTIVES

The aim of the present systematic literature review was to determine whether long-term treatment results with single-tooth implants may differ depending on the timing of implant placement in relation to tooth extraction (immediate IP/early EP/delayed DP) and the timing of prosthetic loading (immediate IL/early EL/delayed DL).

MATERIAL AND METHODS

Electronic and manual searches were performed to identify studies reporting on long-term results (survival rate and/or marginal bone resorption after ≥3 years) of maxillary single-tooth implants in the aesthetic zone using defined placement and loading protocols. Comparative trials were subjected to meta-analyses whilst data from single-arm studies were pooled to evaluate differences between timing protocols.

RESULTS

A total of 7 controlled trials were considered for meta-analyses: immediate loading was compared to delayed loading in 3 studies on immediate placement (IPIL vs. IPDL, p = .306) and in 2 studies on delayed placement (DPIL vs. DPDL, p = 1.000) whilst 2 studies compared early versus delayed placement with delayed loading (EPDL vs. DPDL, p = .600), however, without significant differences. Pooled data analysis of 29 studies (965 implants) did not show differences between timing of placement or loading as well as marginal bone remodelling. No impact of the one abutment - one time concept, flap design and simultaneous bone or soft tissue augmentation could be established.

CONCLUSIONS

Insufficient data are available for meta-analytic comparison of all combinations of implant placement and loading protocols.

An open, randomised, multi-centre study, comparing straight and tapered apex implants design, in partially and totally edentulous maxillae

The design of the commercially available implant OsseoSpeed^® (control) was changed to a tapered apex with a smaller apical diameter; OsseoSpeed^® TX (test).

OBJECTIVE

The present study evaluated the clinical outcome of marginal bone level as primary outcome, and cumulative implant survival rate, primary stability and condition of the peri-implant mucosa as secondary outcomes, one year after loading.

MATERIAL AND METHODS

92 subjects (150 implants, ten centres), with partially or totally edentate maxillae were randomized to receive either test or control implants. One to six implants were placed in each subject using a one-stage surgical procedure. Subjects received a permanent prosthesis 10-12 weeks after implant placement and were followed for one year.

RESULTS

47 subjects in the test group received 82 implants and 45 subjects in the control group received 68 implants. Marginal bone level alterations from loading to 1-year follow-up was -0.02 × 0.41 mm (mean × SD) and -0.03 × 0.38 mm (mean × SD) for the test and the control group, respectively, indicating no difference between the groups. Non-inferiority was declared as confidence interval for the difference between control and test implants was no worse than 0.5 mm. The CSR was 98.8% in the test group and 100% in the control group, with no statistically significant difference between the groups.

CONCLUSIONS

Change of the apical design of a commercially available implant showed no significant effect on marginal bone level and CSR compared to the control implant. Missing data and many investigators may have influenced on the result. Trial registration number: NCT01324778.

Clinical and radiographical performance of implants placed with simultaneous guided bone regeneration using resorbable and nonresorbable membranes after 22-24 years, a prospective, controlled clinical trial

Aim

The aim was to evaluate the performance of implants placed with simultaneous guided bone regeneration (GBR) using resorbable or nonresorbable membranes compared to implants placed in pristine bone without bone regeneration after an observation period of 22–24 years.

Material and Methods

The patient cohort of this clinical trial was treated from 1994 to 1996. Dehiscence defects were treated with GBR by either using resorbable collagen membranes (BG) or nonresorbable ePTFE membranes (GT). Implants placed in pristine bone served as a control (CT). Clinical parameters, marginal bone levels, and technical outcomes were evaluated following restoration placement and at the present follow‐up. A 3D radiographic analysis was conducted in order to assess buccal and oral bone dimensions. Implant survival was assessed with Kaplan–Meier analysis and a frailty model (level of significance 5%).

Results

Out of the originally 72 patients (mean age 75.4 ± 15.70 years) with 265 implants, 39 patients with 147 implants were included in the study after a median period of 23.5 years. Implant survival was 89.3% in group BG (n = 100), 90.2% in group GT (n = 37), and 93.8% in group CT (n = 105), without significant differences (Frailty proportional hazard model p = .79). Smoking had a negative effect on survival (p = .0122). Mean vertical marginal bone levels were −2.3 ± 1.4 mm (BG, n = 59), −3.0 ± 1.5 mm (GT, n = 21), and −2.3 ± 1.6 mm (CT, n = 52). The vertical buccal bone levels were −3.0 ± 1.9 mm (BG, n = 57), −3.5 ± 2.2 mm (GT, n = 21), and −2.6 ± 1.8 mm (CT, n = 49), without significant differences.

Conclusion

Implant placement with GBR procedures provides treatment outcomes with favorable implant survival rates (89.3%–93.8%) after 23.5 years. Smoking, however, affected implant survival negatively.

The effect of implant-abutment connections on peri-implant bone levels around single implants in the aesthetic zone: A systematic review and a meta-analysis

Objective

To systematically review literature about the effect of different implant‐abutment interface designs on peri‐implant bone level changes, implant loss and mid‐buccal mucosa changes around single implants in the anterior maxilla. Reviewing three connection configurations: Platform switched conical (PS‐conical); Platform switched parallel (PS‐parallel); Platform matched parallel (PM‐parallel).

Methods

A detailed search was carried out in Pubmed, EMBASE, Cochrane, Scopus, Open Gray and African journals Online (until December 1, 2020) and was restricted to clinical prospective studies of at least 1 year and with at least 10 human participants. A meta regression analysis was carried out primarily on the pooled peri‐implant bone level changes followed by implant loss and mid‐buccal mucosa level change. Risk of bias was assessed with RoB 2.0 and ROBINS‐I. The manuscript complied with the PRISMA guidelines and was registered in the PROSPERO database (ID: 225092).

Results

A total of 5513 hits gave 44 eligible articles for the analyses. Bone level change did not differ significantly between the two platform switched connections; their bone loss scores were significantly lower than PM‐connection. The PS‐conical connections have significantly lower implant losses than the PM connection. Mid‐buccal mucosa level change was comparable between the three connection configurations. Moderate to high risk of bias was detected in the included studies.

Conclusions

The performance of PS‐conical and PS‐parallel connection configurations both favored bone loss scores compared to the PM‐parallel connection configuration. All three demonstrated mid‐buccal mucosa changes that were small and did not differ significantly amongst the groups.

Short vs. regular length implants to rehabilitate partially edentulous mandible: a 2-year prospective split-mouth clinical study

Many studies have evaluated short implants (SIs); however, it is still unclear whether SIs are reliable and can be used to simplify surgical and prosthetic protocols with successful clinical outcomes. The aim of this non-random, conveniently sampled, prospective, split-mouth study was to compare the clinical outcomes when short (SI) (≤8 mm) or regular-length implants (RIs) (>10 mm) were used in the posterior mandible two years after the delivery of splinted reconstructions. Each participant (N=10) received four implants in the posterior mandible; two SIs were placed on one side, and two RIs were placed contra-laterally. Implants were restored with splinted, screw-retained, porcelain-fused-to-metal reconstructions. Survival and success rates, peri-implant marginal bone level (MBL), and soft tissue parameters were evaluated. No participant drop-outs were recorded. Both types of implants showed 100% success and survival rates. From prosthetic delivery to 24 months post-loading, bone remineralization of +0.40 mm for the SIs and +0.36 mm for the RIs was observed without statistically significant differences in MBL between the implant types (p=0.993). SIs showed significantly higher (p=0.001) clinical attachment level (CAL) and probing depth (PD) values. Chipping occurred in one situation in the RI group resulting in a 97.5% prosthetic success rate, which was 100% for the SIs. After 2 years, SIs with splinted reconstructions showed comparable clinical outcomes to those of RIs. Further long-term controlled clinical studies with balanced experimental designs evaluating random and larger populations are required to corroborate these findings.

Bibliometric analysis of the scientific production of literature on peri-implant diseases in the Web of Science

BACKGROUND

The exponential increase in implant placement worldwide and the high prevalence of its associated pathologies have prompted an increasing contribution by the scientific community to the number of publications related to peri-implant pathologies.

PURPOSE

The objective of this work is to carry out a bibliometric analysis of scientific production on peri-implant diseases.

MATERIALS AND METHODS

The search strategy included titles, keywords, and abstracts based on the term peri-implantitis and all the possible combinations existing in Science Citation Index Expanded (SCIE) of the main collection of Web of Science. Two limits were established: the document typology was limited to Article and Review, and articles published up to 2019 were selected. All articles were refined and standardized manually to avoid typographical errors and duplications in authors' names or institutions.

RESULTS

The total number of papers collected was 2547. A significant increase was observed in the number of articles published, especially in the past 10 years. The three most productive authors were Europeans, and the 45 most productive institutions were the universities. The most productive funding entities were the governments. Of the published works, 42.28% were funded. Of the 2547 records, 86.53% presented keywords.

CONCLUSIONS

Scientific literature on peri-implantitis shows scientific growth in recent years, with a growing trend towards collaboration between authors and institutions. Most of the works have been published in high-impact journals, and in the last 2 years, more than half of the works have received some type of public or private funding.

Cross-sectional evaluation of clinical and immunological parameters at partially microgrooved vs machined abutments in humans

OBJECTIVE

The objective of the present study was to examine the clinical and immunological parameters in samples collected from the peri-implant crevicular fluid (PICF) of machined titanium (M) abutments compared to titanium abutments with a laser-microtextured surface (LMS) on dental implants.

MATERIAL AND METHODS

A total of 40 patients with one titanium implant, half of them (n=20) provided with a M abutment (control group) and the other half (n=20) with LMS abutments (test group), were included in the study. Clinical parameters pocket probing depth (PD), full-mouth plaque score (FMPS), radiographic bone loss (RBL), clinical attachment level (CAL), mucosal recession (MR), bleeding on probing (BOP), and width of keratinized mucosa (KM) were evaluated. The peri-implant sulcus fluid was analyzed for cytokines IL-1α, IL-1β, IL-6, IL-8, and IL-10 via flow cytometry.

RESULTS

Clinical evaluation demonstrated no significant difference of PD (mean LMS = 3.50 mm/SD 0.95 mm vs mean M = 3.45 mm/SD 0.76 mm (p=0.855)), MR (mean LMS = 0.30 mm/SD 0.57 mm vs mean M = 0.35 mm/SD 0.67 mm (p=0.801)), CAL (mean LMS = 3.60 mm/SD 1.14 mm vs mean M = 3.55 mm/SD 0.89 mm (p=0.878)), and KM (mean LMS = 2.03 mm/SD 1.08 mm vs mean M = 2.13 mm/SD 0.92 mm (p=0.754)) between LMS and M abutments. LMS abutments showed less BOP than M abutments (26.7% vs 30.8%), but statistically not significant (p = 0.2235). Radiographic bone loss (mean LMS = 0.22 mm/SD 0.44 mm vs mean M = 0.59 mm/SD 0.49 mm) was reduced in the test group in comparison with the control group (p=0.016). In the collected PICF, the levels of pro-inflammatory cytokines IL-1α (median LMS = 180.8 pg/ml vs M = 200.9 pg/ml (p=0.968)) and IL-1β (median LMS = 60.43 pg/ml vs M = 83.11 pg/ml (p=0.4777)) were lower, and the levels of IL-6 (median LMS = 180.8 pg/ml vs M = 200.9 pg/ml (p<0.0001)) were significantly lower in the test group. In contrast, the levels of IL-8 (median LMS = 255.7 pg/ml vs M = 178.7 pg/ml (p=0.3306)) were higher in the test group, though not significantly. The levels of anti-inflammatory IL-10 were significantly increased in the test group (LMS median = 0.555 pg/ml vs M median = 0.465 pg/ml (p=0.0365)). IL-1β showed a significant correlation to radiologic bone loss (p=0.0024). The other variables IL-1α, IL-6, IL-8, and IL-10 had no significant correlation to radiological bone loss.

CONCLUSION

Within the limitations of this study, titanium implants provided with laser-microtextured surface abutments seem to demonstrate less pro-inflammatory and more anti-inflammatory activity and to show reduced radiographic bone loss compared to machined titanium abutments.

CLINICAL RELEVANCE

The use of laser-microtextured surface abutments might have the potential to support peri-implant tissue health.

Scientometric Analysis of Dental Implant Research over the Past 10 Years and Future Research Trends

BACKGROUND

We conducted a bibliometrics analysis to explore the recent trends in dental implant research which could help researchers have a clear grasp of the relevant research hotspots and prospects. Material and Methods. Altogether, 15,770 articles on dental implants, from January 1, 2010, to October 31, 2019, were selected from the Web of Science Core Collection. We used BICOMB software to extract the high-frequency MeSH terms and construct binary and coword matrices. gCLUTO software was used for biclustering and visual analysis, Ucinet 6 software for social network analysis, SCIMAT software for strategic diagram building, Citespace 5.5 software to form timeline visualization, and VOSviewer software, eventually, for bibliometrics cocitation network.

RESULTS

Altogether, 72 high-frequency keywords were extracted from the selected articles and 4 clusters and 7 subcategories were identified through biclustering analysis in the dental implant research field. The use of the strategic diagram also enabled us to find the research hotspot and development trends.

CONCLUSIONS

The survival rate of dental implants and subsequent restoration have always been the core focus of research. Sinus floor elevation and guided bone regeneration are worthy of constant exploration owing to their reliability. With continuous improvement in technology, immediate loading could become a future research hot spot.

Need for lateral bone augmentation at two narrow-diameter implants: A prospective, controlled, clinical study

OBJECTIVES

To detect the potential influence of implant diameter and anatomic factors on the need for bone augmentation procedures (BAPs) when replacing congenitally missing lateral incisors (MLIs).

MATERIALS AND METHODS

Patients with congenitally missing MLIs with a mesio-distal distance between the canine and the central incisor of 5.9-6.3 mm received a Ø2.9 mm implant while Ø3.3 mm implants were placed when the distance was 6.4-7.1 mm. The following linear measurements were recorded using a calliper: width of the alveolar process (WAP), width of the bony alveolar ridge (WAR) and thickness of the facial bone after implant osteotomy (TFB). Guided bone regeneration was performed in case of fenestration- or dehiscence-type defects or a thin TFB (<1.7 mm).

RESULTS

Fifty Ø2.9 mm and 50 Ø3.3 mm were included in 100 patients. WAP and WAR did not differ between the groups (p > .05). TFB was statistically significant larger in the Ø2.9 group (1.75 ± 0.59 mm) compared to the Ø3.3 group (1.5 ± 0.63 mm) (p = .041). Fenestration-type defects (p = .005) and a thin facial bone wall (p = .045) was observed more frequently in the Ø3.3 compared to the Ø2.9 group. Correspondingly, BAP was indicated more frequently in the Ø3.3 compared to the Ø2.9 group (p = .017). WAP, MD and WAR were statistically significant correlated to the need for BAP (p < .001). As independent variable, only WAR influenced the probability of BAP (p < .001).

CONCLUSION

The use of 2.9 diameter implants was correlated to a reduced frequency of BAP compared to 3.3 mm implants, without reaching a statistically significant difference. Measurement of the WAP provides the clinician useful information to predict BAP.

The risk for infraposition of dental implants and ankylosed teeth in the anterior maxilla related to craniofacial growth, a systematic review

BACKGROUND

The aim of the study was to evaluate a potential association between individuals with different craniofacial types or other exposures, and the risk of infraposition due to continued growth/eruption of adjacent teeth in the anterior maxilla.

MATERIALS AND METHODS

This is a systematic review in which primary studies as well as other systematic reviews are scrutinised. A search of PubMed (Medline), Scopus, Web of science and Health technology assessment (HTA) organisations and a complementary handsearch was carried out. Selected studies were read in full-text by several reviewers. The quality of the included primary studies was assessed using a protocol for assessment of risk of bias in exposure studies.

RESULTS

The literature search resulted in 3,296 publications. Title and abstract screening yielded 25, whereof one systematic review, potential publications allocated for full-text inspection. The quality assessment resulted in a total of seven studies with a low/moderate risk of bias and four studies with a high risk of bias.

CONCLUSION

In conclusion, a long-term risk for infraposition of dental implants, or ankylosed teeth, among natural teeth can be observed in some cases. The predisposing factors are still not fully understood since the current scientific evidence is very limited.

Clinical performance of single implant-supported ceramic and metal-ceramic crowns: A systematic review and meta-analysis of randomized clinical trials

STATEMENT OF PROBLEM

Evidence relating to the choice of materials for single implant-supported crowns is sparse.

PURPOSE

The purpose of this systematic review and meta-analysis was to assess articles that compared the clinical performance of ceramic and metal-ceramic (MC) implant-supported single crowns with regard to prosthesis failure, complication rate, and patient satisfaction.

MATERIAL AND METHODS

A comprehensive search of databases (PubMed/MEDLINE, Scopus, and Cochrane Library) was performed. The last search was conducted in December 2019. Randomized clinical trials comparing ceramic and MC implant-supported single crowns with at least a 12-month follow-up were included, all of which were published in English. The pooled effects were presented as both a risk difference (RD) and mean difference according to the type of data with 95% confidence intervals (CIs).

RESULTS

Seven randomized clinical trials fulfilled the eligibility criteria and were included in the meta-analysis. The pooled data did not show any statistically significant differences concerning prosthesis failure (RD: 0.000, 95% CI: -0.05 to 0.06), marginal bone loss (mean difference [MD]: -0.02, 95% CI: -0.75 to 0.35), mechanical complications (RD: -0.06, 95% CI: -0.18 to 0.07), biological complications (RD: 0.02, 95% CI: -0.07 to 0.11), or patient satisfaction (MD: 4.86, 95% CI: -2.86 to 12.58).

CONCLUSIONS

Ceramic and MC crowns had similar outcomes with regard to prosthesis failure, mechanical and biological complication rates, and patient satisfaction. As a result, the selection of single implant crown material depends on the preference of the dentist and patient.

Reproducibility and validity of anterior implant esthetic indices: A review

Background:

The purpose of this review was to narrate about the reproducibility and validity of different indices evaluating esthetic aspects in anterior single implant-supported restorations.

Materials and Methods:

An electronic search of Medline, Scopus, Embase, Cochrane Central, and Web of Science databases was performed using the keywords “dental implants,” “anterior esthetics,” “esthetic score,” and “esthetic index.” Besides, a manual search of dental implant journals was carried out.

Results:

The electronic search revealed 932 titles. After further review, 14 articles fulfilled the eligibility criteria and were included in this review. Because of the heterogeneity of the study designs, interventions, and parameters used for assessment of esthetics, no meta-analysis could be performed.

Conclusion:

Many indices have been proposed for the evaluation of the esthetic aspects of single implant-supported reconstructions in the anterior maxilla. All of them have some advantages and drawbacks that this review pointed out. The evidence level of studies used for the validation of these indices is poor. It is necessary to achieve a consensus on the tools for assessment of the esthetic aspect and perform evidence-based studies to validate an appropriate index.

Effectiveness and clinical performance of early implant placement for the replacement of single teeth in anterior areas: A systematic review

AIM

To assess the effectiveness and clinical performance of early implant placement, 4-8 (Type 2) or 12-16 weeks (Type 3) after extraction, in single anterior sites.

METHODS

Studies reporting on Type 2 and Type 3 implant placement were identified. Findings were summarized in evidence tables. Main outcome was implant survival. Peri-implant soft and hard tissues changes, periodontal parameters, aesthetics and patient-reported outcomes were also evaluated. Quality of reporting of the included studies was evaluated through Consort, Newcastle-Ottawa scale and IHE quality appraisal checklist.

RESULTS

Nineteen eligible articles (seven from one RCT, three from two CCTs and nine from three case series) reporting on 140 patients and 140 implants were included. Type 3 implants showed comparable results to Type 4: 95% vs. 100% survival rates. Studies reported high values of implant survival, minimal technical and biological complications and high aesthetic scores in both short and long-term follow-ups for both Type 2 and Type 3 implant placement. Quality evaluation highlighted important weaknesses in the included trials.

CONCLUSIONS

Limited data on Type 2 and Type 3 implant placement appear to indicate that they can perform well both short and long term. However, the limited number of cases, the significant heterogeneity of the included studies and the high risk of biases importantly reduce the generalizability of the findings. CRD42018117363.

Analysis of trends in implant therapy at a surgical specialty clinic: Patient pool, indications, surgical procedures, and rate of early failures-A 15-year retrospective analysis

OBJECTIVES

To evaluate the patient population over a 3-year period and to compare it to observations of the population at the same clinic over a period of 15 years.

MATERIAL AND METHODS

Records of patients receiving dental implants in the Department of Oral Surgery and Stomatology, University of Bern, between January 2014 and December 2016 were analyzed and then compared with data from patients treated between 2002 and 2004 and between 2008 and 2010. Patients were analyzed for demographics and for indications for therapy, as well as for presence or absence and type of complications. Inserted implants were analyzed for type, length, and diameter, as well as for the number and type of associated tissue regeneration procedures.

RESULTS

Analysis revealed a continuous linear increase in the average age of patients seeking implant treatment. The most common indication for implant therapy was a single-tooth gap (STG) (50.5%), followed by distal extension situations (22.3%) and extended edentulous gaps (20.5%). A total of 60.8% of implants placed needed some type of bone augmentation, and 83.5% of implants placed in the anterior maxilla required simultaneous augmentation. Staged guided bone regeneration (GBR) was only necessary in 7% of the cases. Implant failure rates remained low at 0.6%, with postoperative hematomas being the most common postoperative complication (13.4%).

CONCLUSIONS

The rising demand for dental implants continues as the patient population ages. Single-tooth gaps remained consistently the most common indication for implant therapy in recent years. Proper case selection and evidence-based surgical protocols are essential for high success rates.

A systematic review of the survival and complication rates of zirconia-ceramic and metal-ceramic single crowns

OBJECTIVES

The aim of the present systematic review was to analyze the survival and complication rates of zirconia-based and metal-ceramic implant-supported single crowns (SCs).

MATERIALS AND METHODS

An electronic MEDLINE search complemented by manual searching was conducted to identify randomized controlled clinical trials, prospective cohort and retrospective case series on implant-supported SCs with a mean follow-up time of at least 3 years. Patients had to have been clinically examined at the follow-up visit. Assessment of the identified studies and data extraction was performed independently by two reviewers. Failure and complication rates were analyzed using robust Poisson's regression models to obtain summary estimates of 5-year proportions.

RESULTS

The search provided 5,263 titles and 455 abstracts, full-text analysis was performed for 240 articles, resulting in 35 included studies on implant-supported crowns. Meta-analysis revealed an estimated 5-year survival rate of 98.3% (95% CI: 96.8-99.1) for metal-ceramic implant supported SCs (n = 4,363) compared to 97.6% (95% CI: 94.3-99.0) for zirconia implant supported SCs (n = 912). About 86.7% (95% CI: 80.7-91.0) of the metal-ceramic SCs (n = 1,300) experienced no biological/technical complications over the entire observation period. The corresponding rate for zirconia SCs (n = 76) was 83.8% (95% CI: 61.6-93.8). The biologic outcomes of the two types of crowns were similar; yet, zirconia SCs exhibited less aesthetic complications than metal-ceramics. The 5-year incidence of chipping of the veneering ceramic was similar between the material groups (2.9% metal-ceramic, 2.8% zirconia-ceramic). Significantly (p = 0.001), more zirconia-ceramic implant SCs failed due to material fractures (2.1% vs. 0.2% metal-ceramic implant SCs). No studies on newer types of monolithic zirconia SCs fulfilled the simple inclusion criteria of 3 years follow-up time and clinical examination of the present systematic review.

CONCLUSION

Zirconia-ceramic implant-supported SCs are a valid treatment alternative to metal-ceramic SCs, with similar incidence of biological complications and less aesthetic problems. The amount of ceramic chipping was similar between the material groups; yet, significantly more zirconia crowns failed due to material fractures.

How do peri-implant biologic parameters correspond with implant survival and peri-implantitis? A critical review

Objectives

The aim of this critical review was to evaluate whether commonly used biologic diagnostic parameters correspond to implant survival and peri‐implantitis prevalence.

Materials and methods

Publications from 2011 to 2017 were selected by an electronic search using the Pubmed database of the US National Library of Medicine. Prospective and retrospective studies with a mean follow‐up time of at least 5 years and reporting prevalence of peri‐implantitis as well as mean bone loss and standard deviation were selected. The correlation between reported prevalence of peri‐implantitis and reported implant survival, mean follow‐up time, mean bone loss, mean probing depth, and mean bleeding on probing was calculated. Mean bone loss and standard deviation were used for estimation of proportion of implants with bone loss exceeding 1, 2, and 3 mm.

Results

Full‐text analysis was performed for 255 papers from 4,173 available ones, and 41 met all the inclusion criteria. The overall mean weighted survival rate was 96.9% (89.9%–100%) and the reported prevalence of peri‐implantitis ranged between 0% and 39.7%, based on 15 different case definitions. The overall weighted bone loss was 1.1 mm based on 8,182 implants and an average mean loading time ranging from 5 to 20 years. No correlation was found between mean bone loss and the reported prevalence of peri‐implantitis. The estimated prevalence of implants with bone loss above 2 mm was 23%. The overall weighted mean probing depth was 3.3 mm, and mean weighted bleeding was 52.2%. Only a weak correlation was found between survival and function time (r = −0.49). There was no relation between the probing depth or bleeding and the mean bone loss, mean follow‐up time, and reported prevalence of peri‐implantitis.

Conclusion

Biologic parameters mean probing depth and mean bleeding on probing do not correlate with mean bone loss and this irrespective of follow‐up. Case definition for peri‐implantitis varied significantly between studies indicating that an unambiguous definition based on a specified threshold for bone loss is not agreed upon in the literature.

The clinical performance of all-ceramic implant-supported single crowns: A systematic review and meta-analysis

OBJECTIVE

This review aimed at evaluating the survival and technical complication rates of all-ceramic implant-supported single crowns (SC).

MATERIAL AND METHODS

Three electronic databases were searched for clinical studies conducted at ≥ 15 patients examining implant-supported all-ceramic SCs over ≥ 12 months. Survival rates of implants and restorations plus technical complication rates of SCs were calculated and tested for statistical correlation with confounding variables. Statistical analysis was performed using a negative binomial distribution model to calculate 5- and 10-year survival and complication estimates.

RESULTS

Forty-one included studies reported on implant-supported SCs made of veneered and monolithic high-strength oxide ceramics, monolithic, and veneered glass-based ceramics and of a monolithic resin-nano-ceramic (RNC). Survival estimates for SCs of 93% (95% CI: 86.6%-96.4%) after 5 years and 94.4% (95% CI: 91.1%-96.5%) after 10 years were calculated, corresponding values for implant survival were 95.3% (95% CI: 90.6%-97.7%) and 96.2% (95% CI: 95.1%-97.1%). Technical complication rates after 5/10 years were as follows: chipping 9.0% (95% CI: 5.4%-14.8%)/2.7% (95% CI: 2.1%-3.5%), framework fractures 1.9% (95% CI: 0.7%-4.9%)/1.2% (95% CI: 1%-1.5%), screw loosening 3.6% (95% CI: 1.6%-8.4%)/5.2% (95% CI: 3.6%-7.5%), and decementations with 1.1% (95% CI: 0.4%-2.8%) after 5 years. Some confounding variables influenced the above-mentioned estimates significantly.

CONCLUSIONS

All-ceramic implant-supported SCs showed-with the exception of a RNC material-high survival rates. However, failures and technical complications occurred which have to be considered when informing patients on the treatment with implant-supported all-ceramic SCs.

Peri-implant inflammation and marginal bone level changes around dental implants in relation to proximity with and bone level of adjacent teeth

OBJECTIVES

This retrospective study assessed radiographic bone changes and prevalence of inflammation around teeth and neighbouring implants supporting a single-unit fixed dental prosthesis (FDP), in relation to implant- positioning and characteristics.

MATERIAL AND METHODS

Patients with an implant-supported FDP in function for at least 1 year were recruited. The radiographic horizontal and vertical position of the implants were identified. Probing depth (PD), bleeding on probing (BOP) and radiographic bone level around implants and adjacent teeth at the time of placement, prosthesis delivery, and the most recent review were assessed.

RESULTS

98 patients with 195 implants were evaluated for a mean of 37.8 months. Survival rate was 99.6% and success ranged from 31.3% to 91.3% when different success criteria were utilized. Significantly greater interproximal bone loss around teeth and higher prevalence of interproximal peri-implant inflammation occurred when the horizontal distance of BL implants was <1 mm, but not with TL implants. There was no significant impact of the corono-apical positioning of the implants on marginal bone loss.

CONCLUSION

Proximity of implants to adjacent teeth of <1 mm leads to increased prevalence of inflammation and interproximal bone resorption at the teeth adjacent to bone level implants.

Long-term clinical outcome of single implants inserted flaplessly or conventionally

BACKGROUND

Flapless implant surgery is mostly performed using guided surgical protocols, however, long-term studies on free-handed flapless surgery for single implants are lacking.

PURPOSE

This prospective study evaluates bone level changes, peri-implant health, and complications of solitary implants placed using a conventional flap (F) or flaplessly (FL) after 6-9 years.

MATERIALS AND METHODS

Fifty-three single TiUnite Brånemark implants were originally inserted in 49 patients using an one-stage delayed loading protocol with flap (n = 27, F) or flaplessly (n = 26, FL) based on available bone volume and surgeon's decision-making. Thirty-six patients with 37 implants participated in the prospective follow-up investigation 6-9 years later whereby survival, bone level changes, peri-implant health, and complications were assessed.

RESULTS

After 88 months (range 76-107), all implants were survived. For F and FL combined, the overall average radiographic bone level was above the first implant thread, 1.26 mm apical of the implant-abutment junction (SD 1.08; 0-4.9) and statistically comparable. Bone loss from time of loading was 0.49 mm (SD 1.1; -1.3 to 2.8) for F and -0.89 mm (SD 1.0; -2.8 to 0.7) for FL (P < .01), suggesting regrowth of bone in FL due to initial countersinking. One implant (2.7%) had a probing depth above 5 mm.

CONCLUSION

Free-handed flapless implant surgery for single implants with neighboring teeth is a predictable long-term treatment provided when there is sufficient bone volume.

Retention failures in cement- and screw-retained fixed restorations on dental implants in partially edentulous arches: A systematic review with meta-analysis

PURPOSE

This systematic review aimed to evaluate retention failures in cement- and screw-retained fixed restorations on dental implants in partially edentulous arches.

METHODS

The relevant articles were retrieved from MEDLINE (PubMed), Cochrane Library, and EBSCO electronic databases for articles published from January 1995 to January 2016 and were restricted to randomized controlled trials and retrospective and prospective studies on human subjects that were reported in English. A further hand search was conducted on individual journals and reference list of the articles found. Reviewed studies which reported retention failures in fixed implant-supported prostheses using screw and cement retention mechanism. Information on the type and nature of restoration, as well as different luting cement, were also collected.

RESULTS

Thirty-three articles were finalized, 20 short-term clinical studies (up to 5 years) and 13 long-term studies (≥5 years). Out of 33 studies, 16 studies were included in meta-analysis, 8 in short-term and 8 in long-term studies. The results of the meta-analysis for short-term studies showed statistically significant difference between cement-retained and screw-retained prosthesis, with the forest plot favoring cement-retained prostheses (risk ratio [RR]: 0.26; confidence interval [CI]: 0.09-0.74; P < 0.0001; I2 = 79%). In long-term studies, the forest plot revealed statistically significant difference between both retention systems favoring cement-retained prostheses (RR: 0.31; CI: 0.13-0.76; P = 0.03; I2 = 56%).

CONCLUSION

Analysis of the short- and long-term studies shows lesser retention failures with cement-retained prostheses when compared to screw-retained prostheses. Further, multicentric, high-quality randomized controlled studies with long-term observations and modified cementation protocols can yield higher grades of recommendation to avoid retention failures.

Influence of implant location on the clinical outcomes of implant abutments: a systematic review and meta-analysis

Purpose

To compare the failure events and incidence of complications of different abutment materials in anterior and posterior regions. Failure was defined as complete loss of the abutment requiring replacement by a new abutment.

Materials and methods

Electronic searches using PubMed/Medline and Google Scholar complemented with manual searches were performed with specific search terms. Searches were restricted to publications in English between January 2006 and March 2016.

Results

A total of 863 and 1,264 implants were inserted in the anterior and posterior regions, respectively, in a total of 1,529 patients. No titanium abutments failed in anterior or posterior regions. On the other hand, 1.6% of zirconia abutments failed in the anterior region and 1.5% failed in the posterior region. Technical complications occurred mostly in the posterior region and mostly involved zirconia abutment. Meta-analysis was possible only for zirconia-abutment failure, due to considerable heterogeneity of studies and outcome variables. No significant difference in failure rate was found between anterior and posterior zirconia abutments (risk ratio 1.53, 95% CI 0.49–4.77; P=0.47).

Conclusion

This systematic review and meta-analysis showed similar outcomes of different abutment materials when used in anterior and posterior regions in terms of failure events and biological and aesthetic complications. The only significant finding was the increased incidence of technical complications in the posterior region, mostly involving zirconia abutments. Abutment-screw loosening was the most common technical complication.

Clinical and Radiologic Outcomes of Submerged and Nonsubmerged Bone-Level Implants with Internal Hexagonal Connections in Immediate Implantation: A 5-Year Retrospective Study

PURPOSE

To evaluate the 5-year clinical and radiologic outcome of immediate implantation using submerged and nonsubmerged techniques with bone-level implants and internal hexagonal connections and the effects of potential influencing factors.

MATERIALS AND METHODS

A total of 114 bone-level implants (XiVE S plus) with internal hexagonal connections inserted into 72 patients were included. Patients were followed up for 5 years. A t-test was used to statistically evaluate the marginal bone loss between the submerged and nonsubmerged groups. The cumulative survival rate (CSR) was calculated according to the life table method and illustrated with Kaplan-Meier survival curves. Comparisons of the CSR between healing protocols, guided bone regeneration, implants with different sites, lengths, and diameters were performed using log-rank tests.

RESULTS

The 5-year cumulative implant survival rates with submerged and nonsubmerged healing were 94% and 96%, respectively. No statistically significant differences in terms of marginal bone loss, healing protocol, application of guided bone regeneration, implant site, or length were observed.

CONCLUSIONS

High CSRs and good marginal bone levels were achieved 5 years after immediate implantation of bone-level implants with internal hexagonal connections using both the submerged and nonsubmerged techniques. Factors such as implant length, site, and application of guided bone regeneration did not have an impact on the long-term success of the implants.

Effects of modified abutment characteristics on peri-implant soft tissue health: A systematic review and meta-analysis

Objectives

The purpose of this systematic review was to evaluate the impact of the abutment characteristics on peri‐implant tissue health and to identify the most suitable material and surface characteristics.

Methods

A protocol was developed aimed to answer the following focused question: “Which is the effect of the modification of the abutment design in regard to the maintenance of the peri‐implant soft tissue health?” Further subanalysis aimed to investigate the impact of the abutment material, macroscopic design, surface topography and surface manipulation. Randomised controlled trials (RCTs) with a follow‐up of at least 6 months after implant loading were considered as inclusion criteria. Meta‐analyses were performed whenever possible.

Results

Nineteen final publications from thirteen investigations were included. The results from the meta‐analysis indicated that zirconia abutments (Zi) experienced less increase in BOP values over time [n = 3; WMD = −26.96; 95% CI (−45.00; −8.92); p = .003] and less plaque accumulation [n = 1; MD = −20.00; 95% CI (−41.47; 1.47); p = .068] when compared with titanium abutments (Ti). Bone loss was influenced by the method of abutment decontamination [n = 1; MD = −0.44; 95% CI (−0.65; −0.23); p < .001]. The rest of the studied outcomes did not show statistically significant differences.

Conclusions

The macroscopic design, the surface topography and the manipulation of the implant abutment did not have a significant influence on peri‐implant inflammation. In contrast, the abutment material demonstrated increased BOP values over time for Ti when compared to Zi abutments.