A Technique for Standardized Evaluation of Soft and Hard Peri-Implant Tissues in Partially Edentulous Patients

Marginal changes at bone-level implants supporting dental prostheses with or without intermediate standardised abutments after 36 months: Randomised controlled clinical trial

OBJECTIVE

The objective of this study is to evaluate the changes at marginal bone level at implants restored with screw-retained prosthesis connected directly to the implants or with an intermediate abutment, after 3-year follow-up.

MATERIAL AND METHODS

Thirty-six partially edentulous patients received 72 implants. Each patient received 2 implants and a 2-4-unit screw-retained implant-prosthesis. The test group implants received a screw-retained prosthesis connected directly to the implant shoulder, the control group prosthesis were connected through a 3-mm standardised intermediate abutment. Clinical and radiological data were recorded at baseline and at 6-, 12-, and 36-month follow-up.

RESULTS

At 36 months, the mean marginal bone loss was 0.13 ± 0.18 mm for the control group and 0.20 ± 0.24 for the test group, with no significant differences between groups (p > .05). Clinical variables (Probing Pocket Depth, Bleeding on Probing and Plaque Index) at 36 months also showed no significant difference between groups. Minor complications frequency was 6.7% in the control group and 5.3% in test group. None of the groups suffered from mayor complications. Patient Reported Outcomes (PROs) showed a General Satisfaction mean score in the control group of 9.40 (SD 0.82) and 9.37 (SD 1.06) in the test group with no significant differences between groups.

CONCLUSIONS

Bone-level implants restored with screw-retained partial prostheses with or without intermediate abutments showed similar radiographic and clinical outcomes after 3 years.

Single immediate implant placement in the maxillary aesthetic zone with and without connective tissue grafting: Results of a 5-year randomized controlled trial

AIM

To assess the 5-year effects of grafting connective tissue while undertaking single immediate implant placement and provisionalization at the mid-buccal mucosa level (MBML). Secondary outcomes were buccal bone wall thickness (BBT), marginal bone level (MBL) and patient satisfaction.

MATERIALS AND METHODS

Sixty patients with a single failing tooth in the maxillary anterior region were provided with an immediately placed and provisionalized implant. At implant placement, the patients randomly received either a connective tissue graft from the maxillary tuberosity (n = 30, test group) or no graft (n = 30, control group). The alveolar socket classification was mainly Type 2A. Data were collected before removing the failing tooth (T0 ), and at 1 (T1 ), 12 (T12 ) and 60 (T60 ) months after final crown placement. The primary outcome was the change in MBML compared with the pre-operative situation. Additionally, the change in BBT, MBL, aesthetics (using the Pink Aesthetic Score-White Aesthetic Score), soft-tissue peri-implant parameters and patient satisfaction were assessed.

RESULTS

At the 5-year follow-up, 27 patients could be analysed from each group. In each group, one implant was lost during the osseointegration period, within 3 months of placement, resulting in an implant survival rate of 96.7% in both groups. MBML change at T60 was -0.6 (-1.1 to -0.1) mm in the control group and 0.1 (-0.4 to 0.5) mm in the test group (p = .008). BBT and MBL, aesthetics, soft-tissue peri-implant parameters and patient satisfaction showed stable results and satisfied patients, without clinically relevant differences between the groups.

CONCLUSIONS

This 5-year follow-up study shows that grafting connective tissue when replacing a single failing tooth with immediately placed and provisionalized implant results in favourable peri-implant tissues and fewer MBML changes.

The use of digital technologies in peri-implant soft tissue augmentation - A narrative review on planning, measurements, monitoring and aesthetics

OBJECTIVE

To identify the different uses and modalities of digital technologies to diagnose, plan and monitor peri-implant soft tissue conditions and aesthetics.

METHODS

A comprehensive narrative review of pertinent literature was conducted, critically appraising key digital technologies that may assist peri-implant soft tissue augmentation and assessment. An electronic search on four databases including studies published prior to 1st July 2023 was performed and supplemented by a manual search.

RESULTS

Predominantly, tools such as cone beam computed tomography (CBCT), intraoral scanning (iOS), intraoral ultrasonography and digital spectrophotometry were commonly to assess and monitor peri-implant soft tissues. The main clinical and research applications included: (i) initial assessment of mucosal thickness, supra-crestal tissue height and keratinized mucosa width, (ii) evaluation of peri-implant soft tissue health and inflammation, (iii) monitoring profilometric changes and midfacial mucosal margin stability over time and (iv) aesthetic evaluation through colour assessment. While evidence for some digital tools may be limited, the integration of digital technologies into peri-implant soft tissue management holds great promise. These technologies offer improved precision, comfort and speed in assessment, benefiting both patients and clinicians.

CONCLUSION

As digital technologies progress, their full potential in peri-implant soft tissue augmentation and their value will become more evident with ongoing research. Embracing these innovations and their potential benefits is recommended to ensure that during progress in implant dentistry, patient care is not hindered.

Dental implant treatment for two adjacent missing teeth in the esthetic region: A systematic review and 10-year results of a prospective comparative pilot study

OBJECTIVES

The aim of the systematic review was to compare studies on implant-supported two-unit cantilever crowns with two adjacent implant-supported crowns in the anterior region. The second aim was to assess in a 10-year prospective comparative pilot study, hard and soft peri-implant tissue changes in patients with a missing central and adjacent lateral upper incisor, treated with either an implant-supported two-unit cantilever crown or two single implant-supported crowns.

MATERIALS AND METHODS

Medline, Embase, and the Cochrane Central Register of Controlled Trials were searched (last search March 1, 2023). Inclusion criteria were studies reporting outcomes of two missing adjacent teeth in the esthetic region and treated with a single implant-supported two-unit cantilever fixed dental prosthesis, or with two solitary implant-supported crowns. Outcome measures assessed included implant survival (primary), changes in marginal bone and gingiva level, restoration survival, subjective and objective esthetic scores, papilla volume, mid-facial marginal mucosa level, probing depth, bleeding on probing, and biological and technical complications with ≥1-year follow-up. In addition, in a 10-year pilot study, the same outcome measures were assessed of five patients with a single implant-supported two-unit cantilever crown and compared with five patients with two adjacent single implant-supported crowns in the esthetic zone.

RESULTS

Nine articles with 11 study groups were found eligible for data extraction. Meta-analyses of implant survival rates were 96.9% (mean follow-up 3.4 ± 1.4 years) for the implant-cantilever treatment and 97.6% (mean follow-up 3.0 ± 1.8 years) for the adjacent implants treatment (p = .79). In the 10-year comparative pilot study, no clinically relevant changes in hard and soft peri-implant tissue levels occurred in both groups. Patient satisfaction was also high in both groups.

CONCLUSION

Single implant-supported two-unit crowns can be a viable alternative to the placement of two adjacent single implant crowns in the esthetic zone.

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.

Maxillary overdentures supported by four or six implants in the anterior region: 10-year randomized controlled trial results

AIM

To evaluate bar-supported maxillary implant overdenture treatment when supported by either four or six implants after 10 years.

MATERIALS AND METHODS

Edentulous subjects with maxillary denture complaints and ample bone volume to facilitate implants in the anterior region of the maxilla were planned for implant overdenture treatment, randomized to receive either four implants (n = 25) or six implants (n = 25) and subsequently evaluated after 10 years of function. Outcome variables included peri-implant bone-level changes, implant and overdenture survival, complications, presence of plaque, calculus and bleeding, degree of peri-implant inflammation, probing depth and patient satisfaction. Differences between the groups and between evaluation periods were tested with a Student's t-test.

RESULTS

Fourteen patients with totally 72 implants were lost to follow-up. Two patients from the six-implant group experienced implant loss (four implants), resulting in 96.1% implant survival in this group versus 100% survival in the four-implant group. Clinical, radiographical and patient-reported outcome measures did not differ statistically significant between the two groups. Patients from both groups were generally quite satisfied with the result after 10 years.

CONCLUSIONS

Similar and favourable outcomes are seen in bar-supported maxillary overdentures on either four or six anteriorly placed implants after a 10-year evaluation period.

Maxillary bar overdentures on four or six posterior implants: 10-year results from a randomized clinical trial

OBJECTIVE

To compare clinical and patient-reported outcomes when providing maxillary overdentures on four and six splinted implants placed in the posterior region during a 10-year follow-up period.

MATERIALS AND METHODS

Sixty-six edentulous participants with functional maxillary denture complaints and insufficient bone volume to allow implant placement were scheduled for a bone augmentation procedure. After healing, participants were randomized to receive either four or six implants in the posterior maxilla. After 3 months of osseointegration, a bar overdenture was constructed. Implant survival, overdenture survival, clinical scores, peri-implant bone height changes, and patient satisfaction were assessed.

RESULTS

Forty-six participants completed the 10-year follow-up. Implant survival was 100% in the 4-implant group and 96.7% in the 6-implant group. Seven new overdentures were made in the 4-implant group and 12 new overdentures were made in the 6-implant group due to excessive wear of the denture base and teeth. Clinical parameters did not differ significantly between groups. Mean marginal bone loss compared to baseline was 0.41 ± 0.37 mm in the 4-implant group and 0.70 ± 1.07 mm in the 6-implant group. Overall, patient satisfaction improved significantly, but did not differ between groups.

CONCLUSION

From this 10-year follow-up trial, it was concluded that bar maxillary overdentures on four or six implants in the posterior region of an augmented maxilla resulted in a comparable treatment outcome with high implant survival, limited loss of peri-implant marginal bone, and high patients' satisfaction. (Clinical trial registration number: NTR9729).

Dental implants in dentate primary and secondary Sjögren's syndrome patients: A multicenter prospective cohort study

OBJECTIVES

To prospectively assess the clinical performance and patient-reported outcomes of dental implants in dentate patients with primary and secondary Sjögren's syndrome (pSS and sSS, respectively) compared to patients without SS.

MATERIALS AND METHODS

Thirty-seven implants were placed in 17 patients with pSS/sSS and 26 implants in 17 non-SS patients to replace missing (pre)molars. Clinical performance, marginal bone-level changes, patient satisfaction, and oral health-related quality of life (OHRQoL) were assessed at 1 (T1), 6 (T6), 12 (T12), and 18 (T18) months after placement of the superstructure. Marginal bone-level changes were measured on standardized dental radiographs. Clinical parameters included implant and crown survival, plaque, bleeding and gingival indices, and probing depth. Patient satisfaction and OHRQoL were assessed with validated questionnaires.

RESULTS

Implant survival at T18 was 100% in the patients with pSS/sSS and 96.2% in the non-SS group. Mean marginal bone loss at T18 did not differ between patients with pSS/sSS and non-SS patients, 1.10 ± 1.04 and 1.04 ± 0.75 mm, respectively (p = .87). Clinical performance was good with no differences between the groups for all outcome measures (p > .05). OHRQoL in patients with pSS/sSS had improved significantly after placement of implant supported crowns at all measuring moments compared to baseline (p < .05). Nevertheless, patient satisfaction and OHRQoL remained significantly higher for patients without SS at all measuring moments (p < .05).

CONCLUSION

Dental implants can be successfully applied in dentate patients with pSS/sSS and have a positive effect on OHRQoL.

Single implant-supported two-unit cantilever fixed partial dentures in the posterior region: a retrospective case series with a mean follow-up of 6.5 years

Background

The aim of this retrospective study was to evaluate the implant survival, clinical and radiographic outcomes, and patient satisfaction of single implant-supported two-unit cantilever fixed partial dentures in the posterior region.

Methods

Patients who received a single implant-supported fixed partial denture with a cantilever in the posterior region between January 2004 and February 2018 were included. Survival rate of the implants and the fixed partial dentures and data regarding the marginal bone level, presence of plaque, calculus, bleeding on probing, mucosa health, pocket probing depth, and patient satisfaction were collected during an evaluation visit. Complications were recorded from the medical records.

Results

Twenty-three patients (mean age 64 ± 13 years) with 28 implants could be included in the study. The mean follow-up period was 6.5 ± 4.8 years at the time of data collection. The survival rate of the implants and fixed partial dentures was 100%. Mean marginal bone loss for the mesial and distal side of the implants was 0.41 mm (SD 1.18 mm) and 0.63 mm (SD 0.98 mm) respectively. A high prevalence of peri-implant-mucositis (89.3%) and peri-implantitis (17.9%) was observed as well as a limited number of technical complications. Patients were quite satisfied, as reflected by a mean VAS score of 94.0 ± 7.2 points (range 0–100) and a OHIP-NL49 score of 10.8 (range 0–196).

Conclusions

Single implant-supported fixed partial dentures with a mesial or distal cantilever can be a predictable treatment option in the posterior region, with stable peri-implant bone levels, minor technical complications, and very content patients. However, the prevalence of peri-implant mucositis and peri-implantitis was high.

Trial registration

ISRCTN, ISRCTN79055740, Registered on March 14, 2021 – —Retrospectively registered.

Erythritol airpolishing in the non-surgical treatment of peri-implantitis: A randomized controlled trial

Objectives

To compare erythritol air polishing with piezoelectric ultrasonic scaling in the non‐surgical treatment of peri‐implantitis.

Material and methods

Eighty patients (n = 139 implants) with peri‐implantitis (probing pocket depth (PPD) ≥5 mm, marginal bone loss (MBL) ≥2 mm as compared to bone level at implant placement, bleeding, and/or suppuration on probing (BoP/SoP)) were randomly allocated to air polishing or ultrasonic treatment. The primary outcome was mean BoP (%) at 3 months after therapy (T3). Secondary outcomes were mean SoP (%), plaque score (Plq) (%), PPD (mm), MBL (mm), full mouth periodontal scores (FMPS) (%), levels of 8 classical periodontal pathogens, and treatment pain/discomfort (Visual Analog Scale, VAS). Patients who were considered successful at T3 were additionally assessed at 6, 9, and 12 months. Differences between both groups were analyzed using multilevel statistics.

Results

Three months after therapy, no significant difference in mean BoP (%) between the air polishing and ultrasonic therapy was found (crude analysis β (95% CI) −0.037 (−0.147; 0.073), p = .380). Neither secondary outcomes SoP (%), Plq (%), PPD (mm), MBL (mm), FMPS (%), and periodontal pathogens showed significant differences. Treatment pain/discomfort was low in both groups (VAS score airpolishing group 2.1 (±1.9), ultrasonic 2.6 (±1.9); p = .222). All successfully treated patients at T3 (18.4%) were still considered successful at 12‐month follow‐up.

Conclusions

Erythritol air polishing seems as effective as piezoelectric ultrasonic scaling in the non‐surgical treatment of peri‐implantitis, in terms of clinical, radiographical, and microbiological parameters. However, neither of the proposed therapies effectively resolved peri‐implantitis. Hence, the majority of patients required further surgical treatment.

Immediate single-tooth implant placement with simultaneous bone augmentation versus delayed implant placement after alveolar ridge preservation in bony defect sites in the esthetic region: A 5-year randomized controlled trial

BACKGROUND

It is unclear if an intact buccal bony plate is a prerequisite for immediate implant placement in post-extraction sockets. The aim of this 5-year randomized controlled trial was therefore comparison of peri-implant soft and hard tissue parameters, esthetic ratings, and patient-reported satisfaction of immediate implant placement in post-extraction sockets with buccal bony defects of ≥ 5 mm in the esthetic zone, with delayed implant placement after ridge preservation.

METHODS

Patients presenting a failing tooth in the esthetic region and a buccal bony defect of ≥ 5 mm after extraction were randomly assigned to immediate (Immediate group, n = 20) or delayed (Delayed group, n = 20) implant placement. Second-stage surgery and placement of a provisional restoration occurred 3 months after implant placement in both groups, followed by definitive restorations 3 months thereafter. The follow-up was 5 years. Marginal bone level (primary outcome), buccal bone thickness, soft tissue parameters, esthetics, and patient-reported satisfaction were recorded.

RESULTS

Mean marginal bone level change was -0.71 ± 0.35 mm and -0.54 ± 0.41 mm in respectively the Immediate group and the Delayed group after 5 years (P = 0.202). This difference, and in other variables, was not significant.

CONCLUSIONS

Marginal bone level changes, buccal bone thickness, clinical outcomes, esthetics, and patients' satisfaction following immediate implant placement, in combination with bone augmentation in post-extraction sockets with buccal bony defects of ≥ 5 mm, were comparable to those following delayed implant placement after ridge preservation in the esthetic zone.

Alveolar ridge preservation in defect sockets in the maxillary aesthetic zone followed by single-tooth bone level tapered implants with immediate provisionalization: a 1-year prospective case series

Background

Clinical studies of single-tooth replacement in compromised bone using bone level tapered implants in the aesthetic zone are scarce.

Aim

To assess clinically, radiographically and aesthetically over 1 year the performance of a bone level tapered implant in the maxillary aesthetic zone in sites after alveolar ridge preservation.

Material and methods

Thirty patients (16 male, 14 female) with a failing tooth and large bone defect after removal received alveolar ridge preservation. After 3 months, implants were placed with immediate provisionalization. Definitive restorations were placed after 3 months. The treatment was evaluated 1 year following the definitive restoration.

Results

All the patients attended the 1-year follow-up. One implant was lost (96.7% implant survival rate). The mean implant stability quotient value was 68.9 ± 8.74 at implant placement. The mean marginal bone level change was minor (− 0.07 ± 0.12 mm). The mean mid-buccal mucosa changed with + 0.01 ± 0.45 mm. The median Pink Esthetic Score and White Esthetic Score after 1 year were 6 [4; 7] and 8 [7; 9], respectively. The patients’ mean overall satisfaction (0–100 VAS scale) was 86.6 ± 10.3.

Conclusion

Bone level tapered implants with immediate provisionalization perform well after alveolar ridge preservation in the maxillary aesthetic zone, according to implant stability, clinical, radiographic, aesthetic and patient-centred outcomes.

Trial registration

NTR, NL8755. Registered on 1 January 2016

Biomarker levels in peri-implant crevicular fluid of healthy implants, untreated and non-surgically treated implants with peri-implantitis

AIM

To compare biomarker levels in peri-implant crevicular fluid (PICF) of healthy implants with levels in PICF of implants with peri-implantitis (before and after non-surgical treatment).

MATERIALS AND METHODS

Samples were taken from 20 healthy implants (n = 17 patients) and from 20 implants with peri-implantitis (n = 19 patients) before and 3 months after non-surgical treatment using the Airflow Master Piezon^® (EMS). A Luminex™ assay was used to evaluate pro-inflammatory and anti-inflammatory cytokines IL-1β, TNF-α, IL-6 and G-CSF, collagen degradation enzyme MMP-8, chemokines MCP-1 & MIP-1α/CCL3, bone markers OPG and sRANKL and interferon-γ. Clinical and radiographical characteristics were assessed. A Mann-Whitney U and Wilcoxon signed-rank test analysed between- and within-group differences.

RESULTS

IL-1β and MMP-8 levels were found significantly elevated in implants with peri-implantitis (p = .007; p = <.001, respectively). No difference in levels of TNF-α, IL-6, MCP-1 and MIP-1α/CCL3, OPG and G-CSF between healthy and diseased implants was found. Levels of sRANKL and INF-γ were under the level of detection. None of the biomarker levels improved after non-surgical therapy, and levels of IL-1β and MMP-8 remained high.

CONCLUSION

Implants diagnosed with peri-implantitis have higher levels of IL-1β and MMP-8 in PICF compared to healthy implants. Non-surgical therapy did not influence the inflammatory immune response.

Immediate placement of single implants with or without immediate provisionalization in the maxillary aesthetic region: A 5-year comparative study

Aim

To compare marginal bone level changes around immediately placed and immediately provisionalized implants with immediately placed and delayed provisionalized implants in the aesthetic region after five years of function.

Materials and Methods

Forty patients with a failing tooth in the maxillary anterior region were randomly assigned immediate implant placement with immediate (Group A: n = 20) or delayed (Group B: n = 20) provisionalization. Definitive crown placement occurred three months after provisionalization. The primary outcomes were changes in marginal bone level. In addition, survival rates, buccal bone thickness, soft peri‐implant tissues, aesthetics and patient‐reported outcomes were assessed.

Results

After 5 years, the mean mesial and distal marginal bone level changes were 0.71 ± 0.68 mm and 0.71 ± 0.71 mm, respectively, in group A and 0.49 ± 0.52 mm and 0.54 ± 0.64 mm, respectively, in group B; the difference between the groups was not significant (p = .305 and p = .477, respectively). Implant and restoration survivals were 100%. No clinically relevant differences in buccal bone thickness or in mid‐facial peri‐implant mucosal level, aesthetic and patient outcomes were observed.

Conclusions

The mean marginal bone level changes following immediate implant placement and provisionalization were comparable with immediate implant placement and delayed provisionalization. (www.isrctn.com: ISRCTN57251089 and www.trialregister.nl: NL8255).

Effect of connective tissue grafting on buccal bone changes based on cone beam computed tomography scans in the esthetic zone of single immediate implants: A 1-year randomized controlled trial

BACKGROUND

Connective tissue grafting has a beneficial effect on the peri-implant mucosa, but the effect of grafting the buccal mucosa on buccal bone thickness (BBT) has not been investigated, although BBT is proposed to be a key factor for the soft-tissue contour. The aim of this trial was to assess the outcome of a connective tissue graft (CTG) in the esthetic zone of single immediate implants on the change of BBT according to cone beam computed tomography (CBCT) scan analysis.

METHODS

In a 1-year randomized controlled trial, 60 patients received an immediately placed implant and provisionalization, either combined with CTG (test group) or without CTG (control group). CBCTs were taken preoperatively (T_pre ) and 1 year after definitive restoration (T₂ ). Any change in BBT was assessed at different implant levels. Additionally, the change in mid-buccal mucosal level (MBML) and approximal marginal bone level were assessed.

RESULTS

Fifty-five patients were available for statistical analysis (test group, n = 28; control group, n = 27). At T₂ , the average change in BBT was significantly larger in the test group (-0.84 ± 0.61 mm) than in the control group (-0.46 ± 0.54 mm, P = 0.02). A MBML gain of 0.07 ± 0.85 mm in the test and a MBML loss -0.52 ± 1.16 mm in the control group was observed at T₂ . Average loss of marginal bone was 0.05 ± 0.33 mm and 0.01 ± 0.38 mm, respectively.

CONCLUSIONS

The application of CTG in the esthetic zone of immediately placed and provisionalized implants is accompanied with more loss of BBT, but at the same time better maintains the mid-buccal mucosal level.

Peri-implant marginal bone loss reduction with platform-switching components: 5-Year post-loading results of an equivalence randomized clinical trial

AIM

To compare the clinical performance and marginal bone levels of implants restored with platform-switching (PS) or platform-matching (PM) abutments.

MATERIALS AND METHODS

Adult patients missing two or more adjacent teeth in the posterior mandible received 2-4 CAMLOG SCREW-LINE implants and were randomly allocated to the PM or PS group, receiving the corresponding prosthetic components from surgery onwards. Implants were conventionally loaded with single cemented crowns. Patients were followed annually for 5 years. Outcome measures were marginal bone level changes, implant survival, performance of the prosthetic components and clinical parameters plaque index, sulcus bleeding index and pocket probing depth.

RESULTS

Thirty-three patients received 72 implants in the PM group, and thirty-five patients received 74 implants in the PS group. Sixty patients attended the final appointment, 31 had received PS components and 29 had received PM components with 65 and 63 implants, respectively. Global survival rate was 96.6% with no differences between groups (p = 0.647). After 5 years of functional loading, PS restored implants presented 0.23mm (95% CI: [0.03, 0.43], p = 0.025) lower marginal bone level changes. The two groups were declared non-equivalent.

CONCLUSION

Patients requiring implant supported restorations in healed bounded or free end edentulous gaps of the mandible benefit from the use of PS components in terms of peri-implant marginal bone level maintenance, though it may not be clinically noticeable.

Performance of bone-level implants with conical connections in the anterior maxilla: A 5-year prospective cohort study

OBJECTIVES

To assess clinical, radiographic and aesthetic outcomes, and satisfaction of patients treated with single implant restorations in the maxillary aesthetic region 5 years after final restoration.

MATERIAL AND METHODS

Sixty patients (29 male/31 female, mean age 37 years) with a missing anterior tooth in the maxilla (39 central incisors/10 lateral incisors/5 cuspids/6 first premolars) received a bone-level implant with conical connection. In 29 patients, a bone augmentation procedure was necessary before implant placement (autogenous bone grafts mixed with spongiosa granules). All implants (12 with 3.3 mm diameter/ 48 with 4.1 mm diameter) were loaded after 3 months of submerged healing. The restoration consisted of an individually designed full-zirconia abutment veneered with porcelain. Follow-up with clinical and radiographic assessment was conducted until 60 months after the final restoration. Aesthetic outcome of the restoration was determined with the Pink Esthetic Score-White Esthetic Score (PES-WES). Patient satisfaction was assessed with a VAS scale and satisfaction questionnaire.

RESULTS

Fifty patients completed the 5-year follow-up. Implant survival was 100%, restoration survival 98%. Mean bone-level change was -0.13 ± 0.66 mm with a median (IQR) pocket probing depth of 2.75 [2.25; 3.25]. The mean PES and WES scores were 6.6 ± 1.7 and 7.8 ± 1.5, respectively. Patient satisfaction was high (92.1 ± 7.8 on 100 mm VAS scale). There were no differences between patients with or without a bone augmentation procedure.

CONCLUSION

Bone-level implants with a conical connection are a reliable treatment option in single-tooth replacements in the maxillary aesthetic zone.

Reproducibility of intraoral photography for pink and white tissue assessment - Is it worth the hassle?

PURPOSE

To assess the effect of the shooting angle variation on linear and planimetric measurements of the pink and white tissues on intraoral photographs.

METHODS

From intraoral three-dimensional (3D) scans of the anterior region in 10 patients, ninety-nine two-dimensional (2D) "scan pictures" each were generated with different shooting angles, each varying in 5° horizontal and vertical increments. Eleven intraoral photographs of each patient and tooth site were taken free-hand: one shot at baseline and 5 shots after 3 and 6 months at slightly varying shooting angles. Papilla height (PH) and area (PA) and tooth crown area (TCA) were estimated on all photographs; the "best-match-to-baseline" photograph from those taken at 3 and 6 months was chosen by 6 evaluators.

RESULTS

Within the first 10° of deviation from the baseline shooting angle, measurements on the 2D "scan pictures" distorted ≤0.5 mm for PH and ≤10% for PA and TCA. Compared to baseline, only 6 out of 100 photographs presented ≥0.5 mm difference in PH, none of the TCA measurements showed distortion ≥10%, and only in 4 instances a ≥10% distortion of the PA was observed. Poor to moderate inter- and intra-rater agreement in choosing the "best-match-to-baseline" photograph was found, but photographs with clinically relevant changes were only seldomly chosen.

CONCLUSIONS

Deviations in the shooting angle ≤10° from the baseline shot cause clinically negligible distortions in linear and planimetric measurements. Highly comparable intraoral photographs of the anterior maxillary teeth can be captured "free-hand" in slightly varying perspective, and then selecting the "best-match-to-baseline".

Four or six implants in the maxillary posterior region to support an overdenture: 5-year results from a randomized controlled trial

OBJECTIVE

To compare clinical and patient-reported outcomes when providing maxillary overdentures on four bar- and six bar-connected implants placed in the posterior region during a 5-year follow-up period.

MATERIALS AND METHODS

Sixty-six fully edentulous patients with functional maxillary denture complaints and insufficient bone volume to allow implant placement were scheduled for a maxillary sinus floor elevation procedure with bone from the anterior iliac crest and randomized to receive either four or six implants in the posterior maxilla and four implants in the mandible. After 3 months of osseointegration, a bar-supported overdenture was constructed. Maxillary implant survival, overdenture survival, clinical scores, peri-implant bone height changes and patient satisfaction were assessed.

RESULTS

Sixty patients completed the 5-year follow-up. Implant survival was 100% in the four-implant group and 99.5% in the six-implant group. No new overdentures had to be made in the four-implant group, and three new overdentures were made in the six-implant group due to excessive wear of the denture base and teeth (90.9% overdenture survival). Clinical parameters did not differ significantly between groups. Mean marginal bone loss compared to baseline was 0.58 ± 0.51 mm in the four-implant group and 0.60 ± 0.58 mm in the six-implant group, respectively. Overall, patient satisfaction improved significantly, but did not differ between groups.

CONCLUSION

Following a bilateral maxillary sinus floor elevation procedure, a bar-supported overdenture on four implants in the posterior maxillary region is not inferior to an overdenture supported by six implants after a 5-year evaluation period in patients with functional maxillary denture complaints and marked posterior resorption (Clinical trial registration number: NTR2969).

Immediate placement and provisionalization of implants in the aesthetic zone with or without a connective tissue graft: A 1-year randomized controlled trial and volumetric study

Objective

To volumetrically compare peri‐implant mid‐facial soft tissue changes in immediately placed and provisionalized implants in the aesthetic zone, with or without a connective tissue graft.

Material and methods

Sixty patients were included. All implants were placed immediately after extraction. After randomization, in one group, a connective tissue graft (test group, n = 30) was inserted at the buccal aspect of the implant. The other group (control group, n = 30) received no connective tissue graft. Clinical parameters, digital photographs and conventional impressions were obtained before extraction (T_pre) and at 12 months following definitive crown placement (T₁₂). The casts were digitized by a laboratory scanner, and a volumetric analysis was performed between T_pre and T₁₂.

Results

Twenty‐five patients in each group were available for analysis at T₁₂. Volumetric change, transformed to a mean (±SD) change in thickness, was −0.68 ± 0.59 mm (test) and −0.49 ± 0.54 mm (control) with a non‐significant difference between groups (p = .189). The mid‐facial mucosa level was significantly different between both groups (p = .014), with a mean (±SD) change of +0.20 ± 0.70 mm (test) and −0.48 ± 1.13 mm (control). The Pink Esthetic Score was similar between both groups.

Conclusions

The use of a CTG in immediately placed and provisionalized implants in the aesthetic zone did not result in less mucosal volume loss after 12 months, leading to the assumption that a CTG cannot fully compensate for the underlying facial bone loss, although a significantly more coronally located mid‐facial mucosa level was found when a CTG was performed.

Epicrestal and subcrestal placement of platform-switched implants: 18 month-result of a randomized, controlled, split-mouth, prospective clinical trial

OBJECTIVES

To evaluate the changes in marginal bone levels (MBL) and soft tissue dimension around platform-switched implants with the implant-abutment junction (IAJ) placed at the crest or 1.5-2 mm subcrestally.

MATERIALS AND METHODS

In all, 96 platform-switched implants were placed in either the posterior maxilla or mandible in 48 partially edentulous patients in a split-mouth study. All implants were provisionally restored after 4-5 months and definitively after 6 months (T6). Radiographic assessment of MBL was assessed at implant placement (T0), T6, 12 months (T12), and 18 months (T18) after placement. Mid-buccal soft tissue and papilla measurements were performed at T6, T12, and T18.

RESULTS

In all, 43 patients with 86 implants completed the study. The T18 examination showed an implant survival rate of 100% in both groups. Analysis showed that MBL varied as a function of IAJ location, which indicated more coronal bone levels with subcrestal (2.39 ± 0.08 mm) than with epicrestal placements (0.88 ± 0.08 mm) (p < .05). Greater average marginal bone loss was found in the subcrestal group (0.40 ± 0.07 mm) compared to the epicrestal group (0.13 ± 0.08 mm) although no statistically significant difference was found at T18 (p > .05). Levels of mid-buccal soft tissue had no significant changes over time, regardless of group (p > .05). There was a significant difference in increase in papilla between T6 and T12 and T18 (p = .005 and .001), but not between T12 and T18 (p = .61). These papilla levels and changes were similar between groups (p > .05).

CONCLUSIONS

The MBL changes around platform-switched implants with same geometry were not affected by the epicrestal or subcrestal location of the IAJ. Furthermore, the location of the IAJ did not affect the implant survival and soft tissue dimensions. However, no bone loss was located apical to the IAJ when the implants were placed subcrestally.

The effect of resorbable membranes on one-stage ridge augmentation in anterior single-tooth replacement: A randomized, controlled clinical trial

AIM

To evaluate the effect of resorbable membranes on one-stage ridge augmentation procedures in small (2-4 mm) buccal bony dehiscences in anterior maxillary single-tooth replacement.

MATERIALS AND METHODS

Patients with a buccal bony dehiscence after implant placement in the esthetic zone were randomly allocated to one-stage ridge augmentation with (M+) or without a membrane (M-). Second-phase surgery was performed after 8 weeks, and follow-up was performed 1, 6, and ≥12 months after loading. Outcomes included implant survival and success, complications, clinical and radiographic parameters, esthetic results and patient satisfaction.

RESULTS

Fifty-two patients were randomized to one-stage ridge augmentation with (n = 25) or without use of a membrane (n = 27). No significant differences in implant survival and success have been observed. The risk of having a small mucosal dehiscence was more than six times higher in the M+ group than in the M- group (RR 6.24, 95% CI 0.81 to 48.21). At the last follow-up, the bleeding index (BI) was marginally higher in the M+ group (14/9/2/0) compared to the M- group (24/2/0/0) (U = 205, Z = -2.97, p = .003, r = .42). The median change in marginal bone level was statistically lower in the M+ group (0.06 mm) than the M- group (0.60 mm) at last follow-up (U = 120, Z = -2.73 a p = .006 r = .42). Total pink esthetic index (PES) and white esthetic score (WES) and combined PES/WES were not significantly different between treatment groups at more than 12 months after loading. Only the subcategory root convexity/soft tissue color scored significantly lower in the M+ group (1.5) compared to the M- group (2.0) at the last follow-up (U = 172, Z = -2.34, p = .019 r = .34). No differences were found in patient satisfaction.

CONCLUSION

The use of a resorbable membrane in small buccal bony dehiscences in anterior maxillary single-tooth replacement resulted in less marginal bone loss, but showed more mucosal dehiscences, higher bleeding scores and lower scores on root convexity and soft tissue color after at least one year of loading. No effect was seen on implant survival and success, overall esthetic results, and patient satisfaction. The research protocol was registered at the Dutch Trial Register (NTR) with ID NTR6137.

Effect of connective tissue grafting on peri-implant tissue in single immediate implant sites: A RCT

AIM

To assess the effect of connective tissue grafting on the mid-buccal mucosal level (MBML) of immediately placed and provisionalized single implants in the maxillofacial aesthetic zone.

MATERIALS AND METHODS

Sixty patients with a failing tooth were provided with an immediately placed and provisionalized implant. During implant placement, patients randomly received either a connective tissue graft from the maxillary tuberosity (n = 30, test group) or no graft (n = 30, control group). Follow-up visits were at one (T₁ ) and twelve months (T₁₂ ) after final crown placement. The primary outcome measure was any change in MBML compared to the pre-operative situation. In addition, gingival biotype, aesthetics (using the Pink Esthetic Score-White Esthetic Score), marginal bone level, soft tissue peri-implant parameters and patient satisfaction were assessed.

RESULTS

The mean MBML change at T₁₂ was -0.5 ± 1.1 mm in the control group and 0.1 ± 0.8 mm in the test group (p = .03). No significant differences regarding other outcome variables were observed, neither was gingival biotype associated with a gain or loss in MBML.

CONCLUSIONS

This one-year study shows that connective tissue grafting in single, immediately placed and provisionalized implants leads to less recession of the peri-implant soft tissue at the mid-buccal aspect, irrespective of the gingival biotype (www.trialregister.nl: TC3815).

Dental Implant Surrounding Marginal Bone Level Evaluation: Platform Switching versus Platform Matching-One-Year Retrospective Study

The benefits and feasibility of platform switching have been discussed in several studies, reporting lesser crestal bone loss in platform-switched implants than in platform-matched implants. Objective. The aim of the present study was to observe the changes in vertical and horizontal marginal bone levels in platform-switched and platform-matched dental implants. Materials and Methods. 51 patients received 60 dental implants in the present study over a 1-year period. Measurement was performed between the implant shoulder and the most apical and horizontal marginal defect by periapical radiographs to examine the changes of peri-implant alveolar bone before and 12 months after prosthodontic restoration delivery. Results. These marginal bone measurements showed a bone gain of 0.23 ± 0.58 mm in the vertical gap and 0.22 ± 0.53 mm in the horizontal gap of platform matching, while in platform switching a bone gain of 0.93 ± 1 mm (P < 0.05) in the vertical gap and 0.50 ± 0.56 mm in the horizontal gap was found. The average vertical gap reduction from the baseline until 12 months was 0.92 ± 1.11 mm in platform switching and 0.29 ± 0.85 mm in platform matching (P < 0.05). Conclusions. Within the limitations of the present study, platform switching seemed to be more effective for a better peri-implant alveolar bone vertical and horizontal gap reduction at 1 year.

Anterior single implants with different neck designs: 5 Year results of a randomized clinical trial

BACKGROUND

The design of the implant neck might be significant for preservation of marginal bone.

PURPOSE

To compare the 5-year radiographic and clinical outcome of single anterior implants provided with a smooth neck, a rough neck or a scalloped rough neck.

MATERIALS AND METHODS

93 Patients with a missing anterior tooth in the maxilla were included. At random, patients received an implant with a 1.5 mm smooth neck ("smooth group"), a rough neck with grooves ("rough group") or a scalloped rough neck with grooves ("scalloped group"). Implants were installed in healed sites. Follow-up visits were conducted after final crown delivery and 1 year and 5 years later.

RESULTS

Scalloped implants showed significantly more initial marginal bone resorption. The total amount of bone loss was 1.26 ± 0.90 mm in the smooth group, 1.20 ± 1.1 mm in the rough group and 2.28 ± 0.97 mm in the scalloped group (P < .05). Survival rates were 96.2% for the smooth and scalloped group and 100% for the rough group. Scalloped implants showed deeper pocket depths, more bleeding and more technical complications. There were no differences in esthetic outcome nor in patient satisfaction.

CONCLUSIONS

For anterior single tooth replacements, scalloped implants show less favorable radiographic and clinical outcome compared to regular implants with a smooth neck or rough neck.

Impact of platform switching on inter-proximal bone levels around 8.5 mm implants in the posterior region; 5-year results from a randomized clinical trial

AIM

To assess the medium-term results of 8.5 mm implants supplied with a conventional platform-matched implant-abutment connection or a platform-switched design.

MATERIALS AND METHODS

Eighty patients with one or more missing teeth in the maxillary or mandibular posterior zone were randomly assigned for treatment with implants with a conventional (control group) or platform-switched (test group) implant-abutment connection. Follow-up visits were conducted 1 month, 1 year and 5 years after functional loading. Inter-proximal bone loss, assessed with standardized peri-apical radiographs, clinical parameters, survival of implants and satisfaction of patients were the outcome parameters studied.

RESULTS

After 5 years of loading, five of the 80 patients were lost to follow-up. The inter-proximal bone loss in the test group (0.38 ± 0.61 mm) was comparable to the bone loss in the control group (0.41 ± 0.47 mm; p = 0.201). Remarkably, bone loss has not progressed compared to the 1-year results. Implant survival, clinical parameters and satisfaction of the patients were favourable and comparable for the test and control group.

CONCLUSION

The 5-years results showed that inter-proximal bone resorption was minor and comparable around platform-matched and platform-switched implants, and implant survival, peri-implant health and patients' satisfaction were favourable.

Maxillary overdentures supported by four or six implants in the anterior region: 5-year results from a randomized controlled trial

OBJECTIVE

To compare a four- and six-implant maxillary overdenture after an observation period of 5 years.

MATERIAL AND METHODS

Fifty subjects with functional problems concerning their maxillary denture, who had ample bone volume in the anterior region to place four or six implants, were included and randomly assigned to either group. Implant and overdenture survival, clinical performance, marginal bone loss and patient satisfaction were assessed.

RESULTS

Forty-six patients completed the 5-year follow-up. One implant failed in the six implants group (99.2% survival) and none in the four implants group (100% survival). No overdentures had to be replaced during the observation period and the number of complications was limited. Clinical function was good, with no difference in clinical parameters between the groups. Mean marginal bone resorption was 0.50 ± 0.37 and 0.52 ± 0.43 mm in the four and six implant group respectively.

CONCLUSION

In patients with functional complaints of their maxillary denture, bar-supported overdentures on four implants in the anterior maxillary region were not inferior to overdentures supported by six implants after 5 years of function. Implant survival and patient satisfaction were high, clinical parameters favourable, bone loss and complications to the denture were minor in both groups (Clinical trial registration number: NTR2969).

Bone stability around implants in elderly patients with reduced bone mineral density - a prospective study on mandibular overdentures

OBJECTIVE

The purpose of this prospective clinical study was to determine whether reduced bone mineral density (BMD) is correlated with a higher risk for dental implant therapy in an elderly patient population.

MATERIAL AND METHODS

Seventy-nine patients recruited at the Prince Philip Dental Hospital were provided with 2-implant-supported mandibular overdentures. Skeletal BMD was recorded before the implant therapy. The World Health Organization Osteoporosis Diagnosis Classification (femoral neck score) was utilized to define the osteoporosis status of patients. Periapical radiographs were taken with a special radiographic holder at the time of implant loading (baseline) and at follow-up examinations. The mesial and distal marginal bone levels of each implant were measured. The mean marginal bone loss (mMBL) and greatest marginal bone loss (GBL) of four implant sites at patient level were recorded for data analysis. Clinical examination including plaque score (PI) and bleeding on probing (BOP) was recorded.

RESULTS

Of the 79 patients recruited in the study, the survival rate of implant was 98.7%. Sixty-three patients (79.7%) were finally available for data collection and statistical analyses. The mean follow-up time was 62.9 (SD = 15.2) months with the mean MBL 0.65 mm (SD = 0.67) and mean GBL 1.25 mm (SD = 0.83), respectively. The average BOP and PI of patients were 49.6% (SD = 30.8) and 47.4% (SD = 37.4). Only BOP was found significantly correlated with mMBL (r = 0.321, P = 0.01). Skeletal BMD was not associated with marginal bone loss (mean MBL: r = -0.094, P = 0.466; mean GBL: r = 0.04, P = 0.761).

CONCLUSIONS

Within the limits of this study, osteoporosis was not a contraindication for implant therapy, and reduced skeletal BMD was not associated with increased marginal bone loss around implants or other complications in an elderly population.

Immediate Single-Tooth Implant Placement in Bony Defects in the Esthetic Zone: A 1-Year Randomized Controlled Trial

BACKGROUND

This study aims to assess, with regard to marginal bone level (MBL), whether the outcome of immediate implant placement in bony defects in the esthetic zone was non-inferior to delayed implant placement after 1 year.

METHODS

Forty patients with a failing tooth in the esthetic zone and a labial bony defect of ≥5 mm after removal of a tooth were randomly assigned for immediate (n = 20) or delayed (n = 20) implant placement. Second-stage surgery and provisionalization occurred after 3 months of healing. Follow-up was at 1 month and 1 year after definitive crown placement. The study was powered to detect a difference in MBL of >0.9 mm. Buccal bone thickness, soft tissue peri-implant parameters, esthetic indices, and patient satisfaction were also assessed.

RESULTS

One year after definitive crown placement, MBL loss was 0.56 ± 0.39 mm mesially and 0.74 ± 0.51 mm distally for the immediate placement group and 0.51 ± 0.43 mesially and 0.54 ± 0.45 distally mm for the delayed placement group, respectively (not significant). Regarding differences in means, non-inferiority was observed after 1 year (difference in mean for immediate versus delayed: mesially 0.04 mm [95% confidence interval (CI) = -0.22 to 0.30 mm, P = 0.40]; distally 0.21 mm [95% CI = -0.10 to 0.51 mm, P = 0.58]). No significant differences in the other outcome variables were observed.

CONCLUSIONS

Immediate implant placement with delayed provisionalization was non-inferior to delayed implant placement with delayed provisionalization in labial bony defects of ≥5 mm regarding change in MBL. Although not powered for other outcome variables, no clinically relevant differences were observed in these variables.

Does a large dehiscent implant surface at placement affect the 5-year treatment outcome? An assessment of implants placed to support a maxillary overdenture

The aim of this study was to assess the 5-year clinical and radiographic outcome of implants with a dehiscent surface at implant placement. A total of 26 consecutive patients (mean age 61.6 years; SD 8.0 years) with at least one implant with a dehiscent implant surface of ≥ two thirds of the implant length on the labial side were included. All implants were placed to support a maxillary overdenture. The implants were placed with adequate primary stability and the dehiscent surface was covered with autologous bone, inorganic bovine bone and a resorbable membrane. Outcome measures were soft tissue conditions, change of radiographic marginal bone level and implant survival. Baseline data (at loading, T0) were compared with 1-year (T1) and 5-year (T5) post loading data. Of the 116 implants, 40 implants had no dehiscence, 16 had a buccal dehiscence < two thirds of the implant length, and 60 implants had a dehiscence ≥ two thirds. The peri-implant tissues were healthy and 5-year marginal bone changes were well within normal limits (-0.4 mm; range: -0.8 to -0.1). One implant was lost during the osseointegration period. Even when implants are placed with a dehiscence ≥ two thirds of the buccal implant surface, favorable 5-year peri-implant health can be achieved provided these dehiscences are covered with autologous bone, inorganic bone and a resorbable membrane, and there is good initial stability of the implants.

Effects of Antibiotics on Bone and Soft-Tissue Healing Following Immediate Single-Tooth Implant Placement Into Sites With Apical Pathology

Overprescription of antibiotics can cause bacterial resistance problems, leading to life-threatening illnesses and public health crises. Clinicians often believe antibiotics can prevent dental implant failure and postoperative complications. In conjunction with implant surgery, antibiotics are therefore routinely prescribed for all cases. In this double-blind, randomized controlled trial, the effects of antibiotics on the clinical outcomes of immediate implant placement upon replacing a tooth with an apical pathology were examined to compare antibiotics (n = 10) and placebo (n = 10). In each subject, a tooth with a chronic apical lesion was extracted, thoroughly curetted, irrigated, and replaced with single implant with a screw-retained custom provisional abutment/crown. Postoperative pain/discomfort was measured at 1- and 4-week postsurgical follow-up visits using visual analog scales. Facial alveolar bone and soft-tissue changes were measured using pre- and postoperative cone-beam computerized tomography and impressions. We found survival rates of 100% (antibiotics) and 78% (control). However, there was no statistical difference in means for any clinical outcome (t tests with Bonferroni adjustment for multiple testing), except for midfacial soft-tissue changes: 0.43 mm (SD, 0.76) in the antibiotics group and 1.70 mm (SD, 1.06) in the placebo group (t15 = −2.89, P = .011). The average change of the midfacial alveolar plate was 0.62 mm (SD, 0.46) and 1.34 mm (SD, 0.91) for the antibiotic and placebo groups, respectively, which did not significantly differ statistically. No significant correlation (Spearman correlation) existed between the changes in facial alveolar bone and the facial gingival margin. Antibiotics appear to have little effect on immediate implant treatment outcomes.

Feasibility of immediate placement of single-tooth implants in the aesthetic zone: a 1-year randomized controlled trial

AIM

To assess whether outcome of immediate implant placement and immediate provisionalization after 1 year was non-inferior to immediate implant placement and delayed provisionalization regarding Marginal Bone Level (MBL).

MATERIALS AND METHODS

Forty patients with a failing tooth in the aesthetic zone were randomly assigned for immediate implant placement with immediate (n = 20) or delayed (n = 20) provisionalization. Follow-up was at 1 month and after 1 year. The study was powered to detect a difference in MBL of <0.9 mm. Apart from MBL, soft tissue peri-implant parameters, aesthetic indexes and patient satisfaction were assessed.

RESULTS

After 1 year, MBL changes were -0.75 ± 0.69 mesially and -0.68 ± 0.65 distally mm for the immediate group and -0.70 ± 0.64 and -0.68 ± 0.64 mm for the delayed group respectively (NS). Regarding differences in means, non-inferiority was observed after 1 year (mesially: Group A versus B: difference in mean 0.08 mm (95% CI -0.38 to 0.53, p = 0.71 distally: Group A versus B: difference in mean 0.09 mm (95% CI -0.37 to 0.56 mm, p = 0.66).No significant differences in the other outcome variables were observed.

CONCLUSIONS

This study showed that immediate placement and immediate provisionalization was non-inferior to immediate placement with delayed provisionalization. In addition, although not powered for these outcome variables, no clinically relevant differences in other outcomes were observed (www.isrtcn.com: ISRCTN57251089).

Annual bone loss and success rates of dental implants based on radiographic measurements

OBJECTIVES

Bone loss around dental implants is generally measured by monitoring changes in marginal bone level using radiographs. After the first year of implantation, an implant should have <0.2 mm annual loss of marginal bone level to satisfy the criteria of success. However, the process of measuring marginal bone level on radiographs has a precision of 0.2 mm (or more) owing to variations in exposure geometry, exposure time and observer perception. Therefore, the value of the annual loss may vary considerably, especially when short intervals are considered. This study investigates how the success rate of dental implants depends on the way annual bone loss is calculated.

METHODS

Panoramic radiographs of 82 implant patients with an average follow-up of 10.4 years were analysed. Marginal bone levels near the implants were indicated by one observer. The annual loss of marginal bone level was determined according to four different calculation methods.

RESULTS

The methods yielded success rates of 9%, 45%, 81% and 89%.

CONCLUSIONS

The success rate of dental implants measured on radiographs greatly depends on the details of the calculation method. Without rigorous standardization, annual bone loss and implant success rate are not well defined.

Maxillary sinus floor elevation surgery with BioOss® mixed with a bone marrow concentrate or autogenous bone: test of principle on implant survival and clinical performance

The purpose of this study was to assess implant survival and 1-year clinical performance of implants placed in the posterior maxilla that had been subjected to maxillary sinus floor elevation surgery with bovine bone mineral (BioOss®) mixed with autogenous bone marrow concentrate or autogenous bone. In a randomized, controlled, split-mouth design study, a bilateral sinus floor augmentation procedure was performed in 12 edentulous patients. At random, one side was treated with BioOss® seeded with an iliac crest bone marrow concentrate enriched in mesenchymal stem cells (test side) and the other with BioOss® mixed with autogenous bone (control side). Three to four months after augmentation, 66 implants were placed. Implant survival, plaque, gingival, and bleeding indices, probing depth, and peri-implant radiographic bone levels were assessed at baseline and 12 months after functional loading. During osseointegration, three implants failed on the test side (two patients) and no implants failed on the control side, resulting in 3-month survival rates of 91% and 100%, respectively. No implants were lost after functional loading and no differences in soft tissue parameters or peri-implant bone loss were observed between the control and test sides. After 1 year in function, no clinically relevant differences were observed regarding soft tissue parameters or peri-implant bone loss.

A comparison between 4 and 6 implants in the maxillary posterior region to support an overdenture; 1-year results from a randomized controlled trial

OBJECTIVE

To compare the treatment outcome of 4 vs. 6 bar-connected implants in the posterior region of the maxilla to support an overdenture during a 1-year follow-up period.

MATERIALS AND METHODS

Sixty-six edentulous patients with an insufficient amount of bone volume in the maxilla to place implants were asked to participate in this study. Randomization assigned patients to either 4 or 6 implants. In all patients, a maxillary sinus floor elevation procedure with bone from the iliac crest was performed, and after a 3-month healing period, 4 or 6 dental implants were inserted in the maxillary posterior region in a one-stage procedure. After 3 months of osseointegration, a bar-supported overdenture was constructed. Implant survival, overdenture survival, clinical scores, peri-implant bone height changes and patients' satisfaction were assessed. Study analysis was performed according a non-inferiority design.

RESULTS

All patients completed the one-year follow-up. After a functional period of 1-year, implant survival was 100% in the 4 implants group and 99.5% in the 6 implants group. Overdenture survival was 100% in both groups. Mean clinical scores were very low and did not significantly differ between groups. Mean marginal bone resorption was 0.35 ± 0.31 mm and 0.46 ± 0.34 mm in the 4 and 6 implants group, respectively. Patients' satisfaction improved significantly in both groups, but did not differ between groups.

CONCLUSION

A bar-supported overdenture on 4 implants in the posterior maxillary region is not inferior to an overdenture supported by 6 bar-connected dental implants.

Maxillary overdentures supported by four or six implants in the anterior region; 1-year results from a randomized controlled trial

OBJECTIVE

Comparing treatment outcome of four and six bar-connected implants in the anterior maxillary region to support an overdenture during a 1-year follow-up period.

MATERIAL AND METHODS

Fifty edentulous patients with lack of retention and stability of the upper denture, but with sufficient bone volume to place implants in the anterior maxillary region, were selected. Randomization assigned patients to either four or six implants. Implant survival, overdenture survival, clinical scores, radiographic bone height changes, and patients' satisfaction were assessed.

RESULTS

Forty-nine patients (one drop out) completed the 1-year follow-up. After 1 year, implant survival was 100% in the four implants group and 99.3% in the six implants group (one implant lost). Overdenture survival was 100% in both groups. Mean clinical scores were low and did not differ between groups (independent Student's t-test). Mean marginal bone resorption was 0.24 ± 0.32 mm in the four implants group and 0.25 ± 0.29 mm in the six implants group. Patients' satisfaction had improved in both groups (paired Student's t-test).

CONCLUSION

Bar-supported overdentures on four implants in the anterior maxillary region are not inferior to overdentures supported by six bar-connected implants. Implant survival was high, peri-implant conditions were healthy and patients' satisfaction had increased significantly in both groups.

Clinical, Microbiological and Inflammatory Evidence of the Efficacy of Combination Therapy Including Serratiopeptidase in the Treatment of Periimplantitis

The present study was aimed to evaluate the effect of introducing administration of the proteolytic enzyme serratiopeptidase in the combined mechanical-antibiotic treatment of periimplantitis (PI). Two randomized groups of 64 adults with a diagnosis of PI were studied over a 6-month period. All patients were treated with a combined mechanical and antibiotic protocol for 15 days. The experimental group (EG) was administered antibiotic and serratiopeptidase, while the control group was administered antibiotic alone. To evaluate the effects of the two treatment protocols, clinical and radiographic indices, the concentration of IL-lβ, IL-6 and TNF-α in the gingival crevicular fluid, the amount of total bacteria] DNA and the presence of specific bacteria were assessed at baseline and at 6 months from treatment. Success rates of combined treatments at 6 months were 96.9% and 78.1% for the EG and CG respectively ( P≤0.01). Implants of the EG showed greater enhancement of clinical, microbiological and inflammatory parameters as compared to those of the CG. Microbiological analyses showed that resistance to combined therapy was constantly associated with the isolation of bacterial species that are not common periodontal pathogens (mainly S.aureus and P.aeruginosa). The data demonstrate that the addition of serratiopeptidase to combined mechanical-antibiotic treatment protocols of periimplantitis significantly improves outcomes and suggest that serratiopeptidase acts at different levels during the healing process.

Performance of the Straumann Bone Level Implant system for anterior single-tooth replacements in augmented and nonaugmented sites: a prospective cohort study with 60 consecutive patients

AIM

The purpose of this prospective study was to evaluate radiographic, clinical and aesthetic outcomes and patient satisfaction of cases treated with platform-switched single implant restorations in the aesthetic region of the maxilla. Furthermore, the influence of an augmentation procedure 3 months before implant placement and the type of restoration (screw-retained vs. cement-retained) was evaluated.

MATERIAL AND METHODS

Sixty patients with a missing anterior tooth in the maxilla were treated with a Straumann Bone Level Implant. Bone augmentation was performed in 29 patients at 3 months before implant placement. Implants were loaded after 3 months of submerged healing. Follow-up was conducted at 7 and 18 months after implant placement. Peri-implant mucosa and implant crown aesthetic outcomes were determined using the Implant Crown Aesthetic Index (ICAI) and the Pink Esthetic Score-White Esthetic Score (PES-WES).

RESULTS

No implants were lost. At 18 months after implant placement, mean bone level change was -0.10 ± 0.27 mm and mean probing pocket depth was 2.57 mm. No differences were found between augmented and nonaugmented sites (P = 0.28). The ICAI indicated satisfactory mucosa and crown aesthetics in 67% and 75% of the cases, respectively, while the PES score was 14.4. ICAI mucosa (P = 0.004) and PES (P = 0.02) scores were significantly less favourable for augmented sites compared with nonaugmented sites. Patient satisfaction was high (8.9 ± 1.1 on VAS-score).

CONCLUSIONS

From the present prospective, clinical study, it can be concluded that the Straumann Bone Level Implant shows an excellent survival rate, marginal bone stability and good clinical and aesthetic results. Bone augmentation before implant placement does not lead to more marginal bone loss. However, less favourable pink aesthetic outcomes were found in augmented sites compared with nonaugmented sites, while no differences were found between cement-retained and screw-retained restorations.