Prevalence and risk/protective indicators of buccal soft tissue dehiscence around dental implants

Accuracy of Anterior Immediate Versus Delayed Implant Placement With an Autonomous Robotic System: A Retrospective Study

OBJECTIVE

This study aimed to compare the accuracy of an autonomous robotic system for anterior immediate and delayed implant placement.

METHODS

This retrospective study included patients who underwent anterior dental implant surgery from September 2022 to March 2025 using an autonomous robotic system. Osteotomies performed with the autonomous robotic system in this study were modified by using precision and side-cutting drills, along with repeated lifting of drills to minimize deviations. Linear and angular deviations in two- and three-dimensional space were assessed by matching preoperative planning with postoperative cone beam computed tomography. Postoperative pain and surgical satisfaction were recorded using a 100-mm visual analog scale. The Shapiro-Wilk test, Student's t-test, Mann-Whitney U-test, Pearson's Chi-Square test, and Fisher's exact test were used, and p < 0.05 was considered statistically significant.

RESULTS

This retrospective study included 53 patients (65 implants) who underwent anterior dental implant surgery with the autonomous robotic system (immediate implant placement group: 19 patients, 21 implants; delayed implant placement group: 34 patients, 44 implants). Comparison of deviations in immediate and delayed implantation using the autonomous robotic system showed a mean (± SD) coronal deviation of 0.57 ± 0.19 mm versus 0.49 ± 0.20 mm (p = 0.129), a mean apical deviation of 0.57 ± 0.19 mm versus 0.52 ± 0.21 mm (p = 0.373), and a mean angular deviation of 0.53° ± 0.18° versus 0.61° ± 0.28° (p = 0.742). Postoperative pain and surgical satisfaction were not significantly different between the two groups (p > 0.05).

CONCLUSIONS

The autonomous robotic system demonstrated high and comparable accuracy in both anterior immediate and delayed implantation, with overall patient satisfaction. This could reduce the technical sensitivity of anterior immediate implant placement, enhance precision, and broaden the clinical applications of the autonomous robotic system.

Peri-Implant Soft Tissue Increase at Small Buccal Bone Dehiscences With Either Volume-Stable Collagen Matrix or Connective Tissue Graft: A Randomized Controlled Trial

OBJECTIVES

This randomized clinical study compared the profilometric measurements of the buccal tissue volume at sites augmented using a volume-stable collagen matrix (VCMX) or connective tissue graft (CTG) simultaneously to implant placement in the presence of small buccal bone dehiscence (SBBD ≤ 3 mm).

METHODS

Forty-four patients with SBBD were treated with soft tissue augmentation (STA) simultaneous to implant placement using VCMX or SCTG. Clinical measurements and 3D intraoral scans were collected prior to STA (BL), at 1, 3 months, and 1 year after prosthetic loading. Digital files were superimposed to compare profilometric volume on the buccal profile (primary outcome); peri-implant health, radiographic bone levels, and patient-reported outcome measures (PROMs) were also assessed.

RESULTS

Both treatments achieved a significant STA at 3 months, with a slight decrease observed from 1 month. At 3 months, the mean increase was 1.07 mm (SD 0.22) for VCMX and 1.22 mm (SD 0.44) for the CTG group (p = 0.156). PROMs revealed a difference in the perception of the bleeding at day 1, pain at 2 and 3 days, and swelling at 3 days favoring VCMX (p < 0.05). At 1 year, no intergroup difference in probing pocket depth, bleeding, and recession was detected, but CTG provided higher stability than VCMX in terms of profilometric measurements (0.21 mm [SD 0.32] vs. -0.05 mm [SD 0.36], respectively; p = 0.014) and radiographic bone levels (0.09 mm [SD 0.65] vs. -0.34 mm [SD 0.70]; p = 0.038).

CONCLUSION

For implant placement at posterior sites with small buccal bone dehiscences, CTG and VCMX resulted in an initially comparable volume augmentation and clinical parameters, with VCMX leading to better PROMs. At 1 year, CTG maintained slightly higher profilometric stability and bone levels.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT05466006 (https://classic.

CLINICALTRIALS

gov/ct2/show/NCT05466006).

Preclinical Investigation on the Effect of Collagen Matrix With Polydeoxyribonucleotide at Buccally Positioned Implants

OBJECTIVES

The objective of this study is to investigate the effect of collagen matrix with polydeoxyribonucleotide (PDRN) at two concentrations on keratinized tissue (KT) regeneration for buccally positioned implants in canines.

METHODS

Four implants were placed in the edentulous mandible of five dogs simultaneously with KT removal. The implants were positioned buccally with respect to the ridge crest. After 2 months, KT augmentation was performed applying the following treatment modalities:(1) free gingival graft (FGG), (2) xenogeneic collagen matrix (XCM), (3) XCM loaded with 2 mg/mL PDRN (PDRN2), and (4) XCM loaded with 4 mg/mL PDRN (PDRN4). All animals were sacrificed 3 months later. Outcomes included clinical (KT height) and histomorphometric measurements (KT height/length, level of the mucosa, mucosal thickness, supracrestal soft tissue height).

RESULTS

Clinical and histomorphometric KT formation at 3 months was greatest in groups with FGG (4.70 ± 1.00/3.94 ± 0.93 mm) and PDRN2 (4.85 ± 1.43/3.95 ± 0.87 mm). Group PDRN2 (1.87 ± 1.50 mm) showed a higher marginal mucosal level with respect to the implant platform compared to other groups (range: 0.57 ± 0.97-0.69 ± 1.14 mm). All groups presented a soft tissue thickness of < 2 mm on the buccal aspect of the implants.

CONCLUSIONS

Based on the limitations of this pilot preclinical study, XCM with 2 mg/mL of PDRN demonstrated a potential for KT augmentation.

Are Sleeves Necessary in Static Computer-Assisted Implant Surgery? A Comparative In Vitro Analysis

OBJECTIVES

This study aims to examine differences in trueness and precision between surgical guides with (S) and without sleeves (SL). A secondary aim was to assess the impact of the sleeve-to-bone distance.

MATERIALS AND METHODS

Mandible replicas (n = 120) were printed from an STL file obtained from a clinical CBCT. The mandibles were divided into sleeved (S, n = 60) and sleeveless (SL, n = 60) groups, each further divided into three categories (n = 20 each) with different heights from the guide to the implant platform: 2 mm (H2), 4 mm (H4), or 6 mm (H6). Digital planning and surgical guide design were done for a 4.1 × 10 mm implant for site #30. Post-op positions were captured using a scan body and lab scanner. Angular deviation was the primary outcome, with 3D and 2D deviations as secondary parameters. Statistical analysis included two-sample t-tests, and one-way and two-way ANOVA.

RESULTS

Group S (2.41 ± 1.41°) had significantly greater angular deviation than Group SL (1.65 ± 0.93°; p = 0.0001). Angular deviation increased with sleeve-to-bone distance. H2 deviations were 1.48 ± 0.80° (S) vs. 1.02 ± 0.45° (SL; p < 0.05), H4: 2.36 ± 1.04° (S) vs. 1.48 ± 0.79° (SL; p < 0.05), H6: 3.37 ± 0.67° (S) vs. 2.46 ± 0.89° (SL; p < 0.05). 3D deviation at the implant platform was 0.36 ± 0.17 mm (S) vs. 0.30 ± 0.15 mm (SL; p < 0.05) and at the apex 0.74 ± 0.34 mm (S) vs. 0.53 ± 0.31 mm (SL; p < 0.01). Group SL at H2 had the smallest inter-implant distance (0.53 ± 0.37°), while Group S at H4 had the largest (1.20 ± 0.84°; p < 0.05).

CONCLUSIONS

Sleeveless guides are more accurate than sleeved guides, and angular deviation is influenced by the distance from the guide to the implant platform.

Treatment strategies for dental implant removal: A literature review

Dental implants have been widely used with success, but long-term usage sometimes leads to implant loss. The purpose of this review was to summarize the etiology of early and late failure requiring dental implant removal and the treatment strategies for the removal of failed implants and reimplantation. Early failures are often caused by patient-related factors, such as smoking, diabetes, radiotherapy, bone quality, and periodontitis of the remaining natural teeth. The most common cause of late failure is peri-implantitis, followed by implant fracture and implant malpositioning. Implants should be removed if they are mobile or if their superstructure cannot be maintained (e.g., implant fracture). For peri-implantitis, implant removal should be determined based on the patient's age and esthetic needs, the implant site, and the severity of bone loss. Many reports have been published on implant removal techniques. The reverse torque technique should always be the first choice because of its low invasiveness. The weighted survival rate for the replacement of failed implants is 86.3%, with a much lower survival rate after the second or subsequent implantations. Therefore, patient-specific problems, such as smoking habits and bruxism, should be checked before reimplantation and controlled to the greatest extent possible.

Soft-Tissue Phenotype as a Risk Indicator of Peri-Implantitis and Peri-Implant Soft-Tissue Dehiscence-A Cross-Sectional Study

AIM

To investigate the association, as well as to characterize the associated panel of pro- and anti-inflammatory markers, between the different components of the peri-implant phenotype and the presence of peri-implantitis/peri-implant soft-tissue dehiscence (PISTD).

MATERIALS AND METHODS

A total of 324 implants in 112 patients were included. The following components of the peri-implant phenotype were clinically measured through the use of a manual periodontal probe or a digital calliper: keratinized mucosa width (PIKM-W), mucosal thickness (MT), attached mucosa (AM) and vestibulum depth (VD). The presence of peri-implantitis and PISTD was assessed through clinical and radiographic examination. Mixed-models logistic regression analyses were performed to analyse the association between peri-implant phenotype and the presence of peri-implantitis or PISTD, adjusting for relevant confounders. Multiplex immunoassays were employed to evaluate the peri-implant crevicular fluid levels of a panel of pro- and anti-inflammatory markers.

RESULTS

Peri-implant health, peri-implant mucositis and peri-implantitis were diagnosed in 36.6%, 21.4% and 42% of the patients (classified according to their worst implant) and 35.2%, 34.3%, and 30.5% of the implants, respectively. In the multi-level multiple regression model, the absence of PIKM-W (odds ratio [OR] = 9.24; 95% CI: 2.73-31.28), the absence of attached mucosa (OR = 19.58; 95% CI: 6.12-62.56) and a reduced (<4 mm) vestibulum depth (OR = 2.61; 95% CI: 1.05-6.48) were associated with peri-implantitis. Similarly, the absence of PIKM-W (OR = 6.32; 95% CI: 1.67-23.83), a thin (<2 mm) mucosa (OR = 157.75; 95% CI: 14.06-1769.9) and a reduced vestibulum depth (OR = 3.32; 95% CI: 1.02-10.84) were associated with the presence of PISTD. Implants with PIKM-W = 0 mm showed statistically significantly higher levels of interferon-γ in both regular (≥2 maintenance/year) and irregular (<2 maintenance/year) compliers (p = 0.046 and p = 0.012). In irregular compliers, the absence of PIKM-W was also associated with statistically significantly higher levels of interleukin (IL)-1β and IL-21 (p = 0.016, p = 0.046). These associations were independent of the effect of relevant confounders (e.g., plaque, compliance with maintenance, etc.).

CONCLUSIONS

Within their limits, the present findings indicate that (a) peri-implant soft-tissue phenotype appears to be associated with the presence of peri-implantitis and PISTD, and (b) in the absence of PIKM-W, the inflammatory response seems to be dysregulated and the soft-tissue remodelling up-regulated.

The Bio-Restorative Concept for Implant-Supported Restorations

OBJECTIVE

This study aims to present the bio-restorative approach in implant dentistry, which combines biological and restorative concepts through digital planning. This concept combines periodontal, surgical, and prosthetic variables, aiming to reduce patient morbidity while achieving satisfactory esthetic and functional outcomes in implant-supported restorations in the long term.

OVERVIEW

Implant dentistry evolved from a primarily surgical to a recent prosthetically driven approach. This evolution was partly due to advancements in bone reconstructive techniques and an increased demand for esthetic outcomes. Recently, digital planning has introduced a new paradigm that allows for the full integration of both approaches. The bio-restorative concept considers functional, esthetic, and biological variables in a virtual planning environment. This is achieved through the simultaneous digital assessment of (A) anatomical site characteristics and (B) implant restorative variables. These variables include digital tooth arrangement, soft-hard tissue conditions, implant variables, supra-platform components, and a surgical plan that respects or modifies peri-implant phenotype.

CONCLUSIONS

The bio-restorative concept is intended to improve contemporary implant dentistry by integrating updated biological and prosthetic notions through digital planning. Adopting this paradigm has the potential to redefine the standards in implant dentistry, fostering a holistic and patient-centered approach.

CLINICAL CONSIDERATIONS

It enhances patient and clinician satisfaction through more efficient and less invasive procedures. Significantly, it improves predictability, leading to successful implant-supported restorations in the long term.

Accuracy of open-sleeved vs. closed-sleeved static computer-assisted implant systems in immediate maxillary molar implant placement: An in vitro study

OBJECTIVES

The objective of this study is (1) to compare the accuracy of an open-sleeved static computer-assisted implant system (sCAIS) with a closed-sleeve sCAIS and free-hand approach in immediate implant placement (IIP) of maxillary molar sites and (2) to investigate the influence of socket morphology on these approaches.

MATERIALS AND METHODS

Ninety partially edentulous duplicated maxillary models simulating three different molar sockets (type A, B, and C based on Smith and Tarnow's classification) were investigated. Three modalities, including sCAIS with open-sleeves, sCAIS with closed-sleeves, and free-hand approach, were applied separately to 30 models with 120 sockets. A customized Python script automatically measured the deviations between the virtual and actual implant positions for all 360 implants.

RESULTS

The 3D deviations of sCAIS were significantly influenced by the socket and sleeve types. Both guided groups exhibited significantly less deviation than the free-hand approach. Type A and C sockets resulted in better implant positions than type B socket sites. In type B sockets, the open-sleeve group achieved significantly less deviation compared to the closed-sleeve group, with respect to apical global (1.34 ± 0.53 vs. 1.84 ± 0.59 mm), coronal horizontal (0.68 ± 0.36 vs. 0.93 ± 0.34 mm), apical horizontal (1.21 ± 0.59 vs. 1.74 ± 0.63 mm), and angular (3.30 ± 1.41 vs. 4.41 ± 1.96°) deviations.

CONCLUSIONS

Guided implant surgery significantly reduces deviations during molar IIP compared to free-hand procedures. Furthermore, the use of open-sleeve sCAIS appears to be more effective in minimizing deviations in type B sockets when compared with the closed-sleeve guided system.

The distally anchored connective tissue graft platform for papilla enhancement: A case report

BACKGROUND

As the need for using dental implants to replace single missing teeth grows, so does the demand for greater esthetic results. However, achieving complete interproximal papillae fill in single-tooth implant restorations remains a challenge. The distally anchored connective tissue platform is a novel soft tissue augmentation technique that consists of harvesting an autogenous connective tissue graft from the palate, folding it, and positioning it at the level of the distal occlusal and buccal surfaces with the help of a distal sling suture to the adjacent distal tooth.

METHODS

This case report describes how a maxillary central incisor with compromised hard and soft tissues were replaced using a comprehensive treatment plan.

RESULTS

The clinical outcomes showed stable mucosal margin levels and complete papillae fill. The patient expressed satisfaction with the achieved results.

CONCLUSIONS

The distally anchored connective tissue graft platform performed at the time of implant placement emerges as a viable and effective soft tissue augmentation technique that yields highly esthetic results.

KEY POINTS

Why is this case new information? To the best of our knowledge, this is the first case report in the literature using the distally anchored connective tissue platform. What are the keys to successful management of this case? Adequate diagnosis and decision-making, resulting in a treatment plan focused on reconstructing both soft and hard tissues in a single-tooth implant within the esthetic area, yield favorable clinical, radiological, and patient-reported outcomes. What are the primary limitations to success in this case? The primary limitation of this study is its reliance on a single case report.

An in vitro analysis of the accuracy of static and robot-assisted implant surgery

OBJECTIVES

Robot-assisted implant surgery (RAIS) is purported to improve the accuracy of implant placement. The objective of this study was to compare RAIS with static computer-assisted implant surgery (sCAIS) in a controlled environment.

MATERIALS AND METHODS

A total of n = 102 implants were placed in the same modified typodont (n = 17 repeated simulated implant surgeries with each n = 3 implants per group) using robot-assisted or static computer-assisted implant surgery. The final implant positions were digitized utilizing cone-beam tomography and compared with the planned position. The angular deviation was the primary outcome parameter. 3D deviations at the implant platform level and the apex were secondary outcome parameters. Accuracy in terms of trueness and precision were assessed. Means, standard deviation, and 95%-confidence intervals were analyzed statistically.

RESULTS

The overall angular deviation was 2.66 ± 1.83° for the robotic system and 0.68 ± 0.38° for guided surgery using static guides (p < .001), the 3D-deviation of the implant platform at crest level was for sCAIS 0.79 ± 0.28 mm and RAIS 1.51 ± 0.53 mm (p < .001) and at the apex for sCAIS 0.82 ± 0.26 mm and for RAIS 1.97 ± 0.79 mm (p < .001), respectively.

CONCLUSIONS

Robotically guided implant surgery was less accurate in terms of trueness (planned vs. actual position) and precision (deviations among implants) than traditional static computer-assisted implant surgery in this in vitro study.

Long-term treatment outcomes of single maxillary buccal peri-implant soft tissue dehiscences: A 10-year prospective study

INTRODUCTION

To evaluate the 10-year clinical outcomes following surgical treatment of shallow isolated peri-implant soft-tissue dehiscences (PSTD) at single tissue level dental implants.

METHODS

The baseline population included 16 patients (16 implants) displaying an isolated peri-implant maxillary buccal soft-tissue dehiscence. The recipient bed was prepared with a minimally-invasive split-thickness flap limited to the buccal aspect to stabilize the tuberosity connective tissue graft (CTG) onto the periosteum. At the end of treatment, patients were enrolled in an individualized supportive peri-implant care (SPC) program. The aesthetic outcome was evaluated on photographs by three clinicians using a visual analog scale (VAS).

RESULTS

SPC during the 10-years proceeded uneventfully in all patients. A total of 12 patients completed the 10-year examination, as 3 patients dropped-out and 1 implant was lost. Complete PSTD coverage was obtained at 7 implant sites (i.e., 58%) while the mean PSTD coverage amounted to 89.6% ± 17.1% without statistically significant differences between 1 and 10 years (p > 0.05). Stable peri-implant parameters (i.e., PD and BoP) and full-mouth scores (i.e., FMPS, FMBS) were recorded throughout the observation period (p > 0.05). The aesthetic improvements obtained in the short-term were maintained up to 10 years.

CONCLUSION

Within their limits, the present results indicate that the proposed surgical technique is a simple and reliable treatment option for the treatment of single maxillary buccal PSTDs in selected cases with positive results up to 10 years in patients under regular SPC (NCT04983758-this clinical trial was not registered prior to participant recruitment).

Efficacy of alveolar ridge preservation with xenografts and resorbable socket sealing materials in the esthetic region: A systematic review with meta-analyses

AIM

The present systematic review aimed to identify and summarize the clinical, radiographic, and histological outcomes of alveolar ridge preservation using bone xenografts and absorbable sealing materials compared with spontaneous healing in the esthetic zone.

MATERIALS AND METHODS

Randomized clinical trials (RCTs) fulfilling specific eligibility criteria were included. Two review authors independently searched for eligible studies, extracted data from the published reports and performed the risk of bias assessment (RoB 2 tool). Study results were summarized using random effects meta-analyses.

RESULTS

Thirteen articles concerning 10 RCTs were included, involving a total of 357 participants. Most of studies were considered as "low" risk of bias. Meta-analyses indicated less horizontal (difference in means-MD = 1.88 mm; p < 0.001), vertical mid-buccal (MD = 1.84 mm; p < 0.001) and vertical mid-lingual (MD = 2.27 mm; p < 0.001) bone resorption in alveolar ridge preservation compared to spontaneous healing as assessed clinically. Bone changes assessed radiographically showed consistent results in terms of horizontal (at 1 mm: MD = 1.84 mm, p < 0.001), vertical mid-buccal (MD = 0.95 mm; p < 0.001) and mid-lingual (MD = 0.62 mm; p = 0.05) resorption. Part of the bone resorption in the spontaneous healing group was compensated by soft-tissues, since the observed differences between groups in linear ridge reduction evaluated through cast models superimposition were smaller (MD = 0.52 mm; p < 0.001).

CONCLUSIONS

Alveolar ridge preservation with xenogeneic bone substitutes and non-autogenous resorbable socket sealing materials is efficacious in reducing post-extraction bone and ridge changes in the esthetic region.

Keratinized tissue augmentation using collagen-based soft tissue substitute with/without epidermal growth factor on buccally positioned implants: a pilot preclinical study

OBJECTIVES

To investigate the effect of epithelial growth factor (EGF) with collagen matrix (CM) on the gain of KT for buccally positioned implants in dogs.

MATERIALS AND METHODS

In five dogs, four implants were placed buccally with the whole part of KT excision on the buccal side (two implants per each hemi-mandible). After one month, KT augmentation was performed: 1) free gingival grafts (FGG), 2) collagen matrix (CM) only, 3) CM soaked with 1 μg/g of EGF, and 4) CM soaked with 10 μg/g of EGF (n = 5 in each group). The experimental animals were sacrificed three months post-KT augmentation. Clinical, histologic, and histomorphometric analyses were performed.

RESULTS

The clinical KT zone was the highest in group FGG (5.16 ± 1.63 mm). Histologically, all groups presented buccal bony dehiscence. Regarding newly formed KT, no specific difference was found among the groups, but robust rete pegs formation in some specimens in group FGG. Histomorphometric KT height (4.66 ± 1.81 mm) and length (5.56 ± 2.25 mm) were the highest in group FGG, whereas similar increases were noted in the rest. The buccal soft tissue thickness at the coronal part of the implant did not exceed 2 mm in all groups.

CONCLUSION

All groups presented increased KT zone, but FGG treatment was more favored. The addition of EGF to CM appeared not to enhance KT formation.

CLINICAL RELEVANCE

FGG treatment was more favorable to re-establish the KT zone than other treatment modalities.

Coronally advanced flap versus tunnel technique for the treatment of peri-implant soft tissue dehiscences with the connective tissue graft: A randomized, controlled clinical trial

AIM

To evaluate the efficacy of coronally advanced flap (CAF) versus tunnel technique (TUN) in covering isolated mid-facial peri-implant soft tissue dehiscences (PSTDs).

MATERIALS AND METHODS

Twenty-eight participants presenting with isolated non-molar implants exhibiting PSTDs were enrolled and randomized to receive either CAF or TUN, both with a connective tissue graft (CTG). The primary outcome of the study was the percentage of mean PSTD coverage at 12 months. Secondary endpoints included the frequency of complete PSTD coverage, changes in keratinized mucosa width (KMW) and horizontal mucosal thickness (MT), as assessed with transgingival probing, 3D optical scanning and ultrasonography, professional aesthetic evaluation and patient-reported outcome measures (PROMs).

RESULTS

At 12 months, the mean PSTD coverage of the CAF and TUN groups was 90.23% and 59.76%, respectively (p = .03). CAF-treated sites showed a substantially higher frequency of complete PSTD coverage (p = .07), together with significantly greater gain of KMW (p = .01), increase in MT (p = .02), volumetric gain (p < .01) and professional aesthetic outcomes (p = .01). Both interventions showed an improvement in patient-reported aesthetics and a reduction of the anxiety related to the appearance of the implant compared to baseline, with the CAF group obtaining significantly higher scores (p = .03 for both PROMs).

CONCLUSIONS

CAF + CTG resulted in superior PSTD coverage outcomes, greater gain in KMW and MT, and better PROMs than TUN + CTG for the treatment of isolated PSTDs (ClinicalTrials.gov NCT03498911).

Complications and treatment errors in implant positioning in the aesthetic zone: Diagnosis and possible solutions

Incorrect implant positioning can lead to functional and aesthetic compromise. Implant positioning errors can occur in three dimensions: mesiodistal, corono-apical, and orofacial. Treatment solutions to manage adverse outcomes through positioning errors require an understanding of the underlying conditions and of those factors that may have led to the error being committed in the first place. These types of complications usually occur because of human factors. If errors do occur with adverse aesthetic outcomes, they are difficult and sometimes impossible to correct. Connective tissue grafts to reverse recession defects are only feasible in defined situations. The option to remove and replace the implant may be the only recourse, provided the removal process does not further compromise the site. Error in judgment by the clinician.

Full arch immediate occlusal loading using site specific implants: A clinical series of 10 patients (13 arches)

PURPOSE

Osseointegration of dental endosseous implants has proven to be effective, predictable, and clinically successful. Unloaded healing protocols were originally used in treating edentulous patients. Full arch immediate occlusal loading protocols have been shown to be as effective as unloaded healing protocols. This paper reports on the results, benefits, and limitations of one specific immediate loading protocol using site specific implants for fresh extraction and healed extraction sites.

MATERIALS AND METHODS

Ten consecutive patients [{13 arches} (age range: 64-81 years; average: 70.1) (4 males/6 females) were treated by the first 2 authors in private practice settings. Hopeless teeth were scheduled for extraction with immediate implant placement and immediate loading with insertion of full arch, screw-retained, acrylic resin interim prostheses within 24 hours. Implants were also placed into healed edentulous ridges. Insertion torque values for each implant were recorded. Interim prostheses were removed after at least 3 months of healing. Implants were reverse torque tested (35 Ncm) and evaluated for macroscopic mobility. Definitive full arch prostheses were made. Patients were followed for 21 to 48 months postimplant surgery. Panoramic radiographs were taken immediately postimplant placement and 1 year postoperative.

RESULTS

Thirteen arches were treated; 11 ultrawide diameter implants were placed into molar sockets, 26 inverted body-shift implants were placed into anterior sockets; 25 standard diameter, tapered implants were placed into edentulous sites; 2 zygomatic implants were placed in one patient. The total number of implants placed was 64 (4 preexisting implants were also used and not included in this study). The minimum implant insertion torque value was 20 Ncm. After 12 to 18 months of function (average 14 months), the implant and prosthetic survival rates were 100%. Eight patients were restored with definitive zirconia or acrylic resin hybrid fixed prostheses. Two patients were restored with bar titanium frameworks and removable overdenture prostheses. No prosthetic complications were reported for the definitive prostheses.

CONCLUSIONS

The results of this clinical series with site specific implants and immediate full arch occlusal loading in treating edentulous patients resulted in 100% clinical implant and prosthetic survival rates. According to this study, this protocol can be used with high levels of anticipated success.

The adjunctive effect of a resorbable membrane to a xenogeneic bone replacement graft in the reconstructive surgical therapy of peri-implantitis: A randomized clinical trial

AIM

To evaluate the potential adjunctive effect of a resorbable collagen membrane covering a xenogeneic bone replacement graft in the reconstructive surgical therapy of peri-implantitis.

MATERIALS AND METHODS

Forty-three patients (43 implants) diagnosed with peri-implantitis associated with intra-bony defects were treated with a surgical reconstructive approach that included a xenogeneic bone substitute material. Additionally, resorbable collagen membranes were placed over the grafting material at sites randomly allocated to the test group; conversely, no membranes were placed in the control group. Clinical outcomes, namely probing pocket depth (PPD), bleeding and suppuration on probing (BoP and SoP), marginal mucosal level (REC) and keratinized mucosa width (KMW), were recorded at baseline and 6 and 12 months after surgery. Radiographic marginal bone levels (MBLs) and patient-reported outcomes (PROs) were assessed at baseline and 12 months. A composite outcome (success) was evaluated at 12 months, which included the absence of BoP/SoP, PPD ≤5 mm and reduction of buccal marginal mucosal level (buccal REC) of ≤1 mm.

RESULTS

At 12 months, no implants were lost and treatment success was observed at 36.8% and 45.0% of implants in the test and control groups, respectively (p = .61). Similarly, there were no significant differences between groups in terms of changes of PPD, BoP/SoP, KMW, MBL or buccal REC. Post-surgical complications were observed in the test group only (e.g., soft tissue dehiscence, exposure of particulate bone graft and/or resorbable membrane). Longer surgical times (~10 min; p < .05) and higher levels of self-reported pain at 2 weeks (p < .01) were observed in the test group.

CONCLUSIONS

This study failed to demonstrate the presence of added clinical or radiographic benefits of the use of a resorbable membrane to cover a bone substitute material within the reconstructive surgical therapy of peri-implantitis associated with intra-bony defects.

Minimal invasiveness at dental implant placement: A systematic review with meta-analyses on flapless fully guided surgery

Flapless and fully guided implant placement has the potential to maximize efficacy outcomes and at the same time to minimize surgical invasiveness. The aim of the current systematic review was to answer the following PICO question: "In adult human subjects undergoing dental implant placement (P), is minimally invasive flapless computer-aided fully guided (either dynamic or static computer-aided implant placement (sCAIP)) (I) superior to flapped conventional (free-handed implant placement (FHIP) or cast-based/drill partially guided implant placement (dPGIP)) surgery (C), in terms of efficacy, patient morbidity, long-term prognosis, and costs (O)?" Randomized clinical trials (RCTs) fulfilling specific inclusion criteria established to answer the PICO question were included. Two review authors independently searched for eligible studies, screened the titles and abstracts, performed full-text analysis, extracted the data from the published reports, and performed the risk of bias assessment. In cases of disagreement, a third review author took the final decision during ad hoc consensus meetings. The study results were summarized using random effects meta-analyses, which were based (wherever possible) on individual patient data (IPD). A total of 10 manuscripts reporting on five RCTs, involving a total of 124 participants and 449 implants, and comparing flapless sCAIP with flapped FHIP/cast-based partially guided implant placement (cPGIP), were included. There was no RCT analyzing flapless dynamic computer-aided implant placement (dCAIP) or flapped dPGIP. Intergroup meta-analyses indicated less depth deviation (difference in means (MD) = -0.28 mm; 95% confidence interval (CI): -0.59 to 0.03; moderate certainty), angular deviation (MD = -3.88 degrees; 95% CI: -7.00 to -0.77; high certainty), coronal (MD = -0.6 mm; 95% CI: -1.21 to 0.01; low certainty) and apical (MD = -0.75 mm; 95% CI: -1.43 to -0.07; moderate certainty) three-dimensional bodily deviations, postoperative pain (MD = -17.09 mm on the visual analogue scale (VAS); 95% CI: -33.38 to -0.80; low certainty), postoperative swelling (MD = -6.59 mm on the VAS; 95% CI: -19.03 to 5.85; very low certainty), intraoperative discomfort (MD = -9.36 mm on the VAS; 95% CI: -17.10 to -1.61) and surgery duration (MD = -24.28 minutes; 95% CI: -28.62 to -19.95) in flapless sCAIP than in flapped FHIP/cPGIP. Despite being more accurate than flapped FHIP/cPGIP, flapless sCAIP still resulted in deviations with respect to the planned position (intragroup meta-analytic means: 0.76 mm in depth, 2.57 degrees in angular, 1.43 mm in coronal, and 1.68 in apical three-dimensional bodily position). Moreover, flapless sCAIP presented a 12% group-specific intraoperative complication rate, resulting in an inability to place the implant with this protocol in 7% of cases. Evidence regarding more clinically relevant outcomes of efficacy (implant survival and success, prosthetically and biologically correct positioning), long-term prognosis, and costs, is currently scarce. When the objective is to guarantee minimal invasiveness at implant placement, clinicians could consider the use of flapless sCAIP. A proper case selection and consideration of a safety margin are, however, suggested.

Effect of sub-marginal instrumentation before surgical treatment of peri-implantitis: A multi-centre randomized clinical trial

AIM

The present multi-centre randomized clinical trial with 12 months of follow-up aimed at studying the added effect of sub-marginal instrumentation before surgical treatment of peri-implantitis.

MATERIALS AND METHODS

Forty-two patients diagnosed with peri-implantitis were recruited. After a behavioural intervention phase including oral hygiene instructions, patients were randomized to either receiving supra- and sub-marginal instrumentation on their affected implants (control group: 21 patients and 29 implants) or only supra-marginal instrumentation (test group: 21 patients and 24 implants), before undergoing surgery. Changes in the deepest probing pocket depth (PPD) with respect to baseline and a composite outcome of treatment success (no implant loss, no bone loss &gt; 0.5 mm, no bleeding or suppuration on probing [BoP/SoP], and PPD ≤ 5 mm) at the 12-month examination were regarded as the primary outcomes of the trial.

RESULTS

At the 12-month examination, changes in the deepest PPD with respect to baseline amounted to -2.96 mm in the control group and to -3.11 mm in the test one (MD = -0.16; SE = 0.56; p = .769), while 21.4% of the implants in the control group and 33.3% in the test group presented treatment success (OR = 1.83; SE = 1.15; p = .338). With the exception of a longer non-surgical treatment duration in the control group (differences in  = -14.29 min; SE = 2.91; p &lt; .001), no other secondary (e.g., soft-tissue recession, keratinized mucosa height, and bone level changes, as well as BoP, SoP, profuse bleeding and implant loss rates) or exploratory (i.e., early wound healing, aesthetics, surgical and total treatment duration, surgery difficulty, intra-operative bleeding, and adverse events) outcome demonstrated statistically significant differences between groups.

CONCLUSIONS

The present multi-centre randomized clinical trial did not demonstrate an added effect of performing sub-marginal instrumentation 6 weeks before the surgical treatment of peri-implantitis. Larger clinical trials are however needed to confirm the present findings (Clinicaltrials.gov: NCT03620331).

Oral health-related quality of life following peri-implantitis surgery; a prospective study

AIM

The aim of this prospective study was to describe long-term patient-reported outcomes following surgical treatment of peri-implantitis.

METHODS

Oral health related quality of life (OHRQoL) of 43 patients diagnosed with peri-implantitis was recorded using the short form of the Oral Health Impact Profile (OHIP-14), where low scores indicate low impact. A Norwegian version of the OHIP-14 form was filled out 1 week before and 6-, 18- and 36 months after the peri-implant surgery. The mean and median OHIP-14 scores were calculated for its seven domains (i.e Functional limitation, Physical pain, Psychological discomfort, Physical disability, Psychological disability, Sosial disability and Handicap) across four different time-points. The dataset was analyzed to find correlations between independent variables and the OHIP-scores.

RESULTS

The OHIP-14 scores were at a low level from baseline to 36 months post-surgery. The mean scores at specific timepoints were at baseline 7.2 (SD 7.3), 6 months post-surgery 6.0 (SD 6.9), 18 months post-surgery 6.8 (SD 9.7) and 3 years post-surgery 7.0 (SD 9.4). None of these changes were statistically significant. Specific domains of OHRQoL did not significantly differ across different time-points (pre- and post-surgery) in males (except for domain 'handicap') or females (except for domain 'functional limitation').

CONCLUSIONS

The reported OHIP-14 measures were initially low and stayed low up to three years after peri-implant surgery. This may indicate that neither the disease nor the treatment deteriorated or improved the OHRQoL.

Occurrence, associated factors and soft tissue reconstructive therapy for buccal soft tissue dehiscence at dental implants: Consensus report of group 3 of the DGI/SEPA/Osteology Workshop

OBJECTIVES

To systematically assess the literature and report on (1) the frequency of occurrence of buccal soft tissue dehiscence (BSTD) at implants, (2) factors associated with the occurrence of BSTD and (3) treatment outcomes of reconstructive therapy for the coverage of BSTD.

MATERIALS AND METHODS

Two systematic reviews addressing focused questions related to implant BSTD occurrence, associated factors and the treatment outcomes of BSTD coverage served as the basis for group discussions and the consensus statements. The main findings of the systematic reviews, consensus statements and implications for clinical practice and for future research were formulated within group 3 and were further discussed and reached final approval within the plenary session.

RESULTS

Buccally positioned implants were the factor most strongly associated with the risk of occurrence of BSTD, followed by thin tissue phenotype. At immediate implants, it was identified that the use of a connective tissue graft (CTG) may act as a protective factor for BSTD. Coverage of BSTD may be achieved with a combination of a coronally advanced flap (CAF) and a connective tissue graft, with or without prosthesis modification/removal, although feasibility of the procedure depends upon multiple local and patient-related factors. Soft tissue substitutes showed limited BSTD coverage.

CONCLUSION

Correct three-dimensional (3D) positioning of the implant is of utmost relevance to prevent the occurrence of BSTD. If present, BSTD may be covered by CAF +CTG, however the evidence comes from a low number of observational studies. Therefore, future research is needed for the development of further evidence-based clinical recommendations.

Etiology and Treatment of Peri-Implant Soft Tissue Dehiscences: A Narrative Review

Implant soft tissue dehiscences compromise not only the aesthetics of the supported restorations but implant survival in the long run. The aim of this narrative review was to briefly present the causative factors of buccal peri-implant soft tissue dehiscences (PSTDs), how these are classified, and the current therapeutic approaches. Implant malposition and the thin peri-implant phenotype are the two major determinants for the occurrence of PSTDs, but other risk factors have also been identified. The most common surgical procedure for treating PSTDs is the split-thickness coronally advanced flap combined with either a connective tissue graft or acellular dermal matrix materials. However, depending on the class and subtype of the dehiscence, the combination of surgical techniques with modifications in the restoration may further ameliorate the final result. In general, within a five-year follow-up period, most techniques lead to a satisfactory aesthetic result, although full coverage of the implant/abutment surface is not always achievable, especially in more extended lesions.

Does guided level (fully or partially) influence implant placement accuracy at post-extraction sockets and healed sites? An in vitro study

OBJECTIVES

The aim of this study is to evaluate the effect of guide level on the accuracy of static computer-aided implant surgery (sCAIS) at post-extraction sockets and healed sites.

MATERIALS AND METHODS

A total of 30 duplicate dental models, with 300 potential implant sites, were used. All the models were equally randomized into three groups: fully guided (FG, n = 100), partially guided (PG, n = 100), and free handed (FH, n = 100) surgeries. After implant placement, the mean global, horizontal, depth, and angular deviations between the virtually planned and actual implant positions were measured automatically by a Python script within software Blender.

RESULTS

Both FG and PG surgeries showed significantly higher accuracy than FH surgery at post-extraction sockets and healed sites. In both sCAIS groups, there were nearly 50% more deviations from implants placed at sockets than those from delayed placement. For the immediate implant placement, the accuracy of sCAIS was significantly affected by the level of guidance. The FG group exhibited lower deviations than the PG group, with a significant difference in coronal global and horizontal deviations (p < .05). For the healed sites, two guided groups exhibited similar outcomes (p > .05).

CONCLUSIONS

sCAISs provide more accuracy than the free-handed approach in position transferring from planning to a model simulation. Full guidance can significantly increase the accuracy, especially at post-extraction sites.

CLINICAL RELEVANCE

Guided protocols showed significantly higher accuracy than free-handed surgery regardless of implantation timing, but both had nearly 50% more deviations in immediate implant placement.

Keratinized mucosa changes around one-stage implants: A prospective case series

BACKGROUND

The need of an adequate band of keratinized tissue (KT) to maintain periodontal health around teeth as well as around implants has been a debated topic over many years but still no conclusions have been drawn.

OBJECTIVES

This prospective case series evaluates the changes undergone by the keratinized mucosa (KM) and the soft tissue volume around non-submerged implants before the prosthetic rehabilitation.

MATERIAL AND METHODS

A total of 40 patients were included. The primary outcome was to analyze the width of the KM at both buccal and lingual aspects compared to the pre-existing KT in the edentulous ridge only in mandibular (pre)molar area. The mucogingival line was marked with a surgical pen and an intra-oral scanner was used to take the impression of the implant area the day of the surgery (T0, baseline) and before the crown placement (T1, 3 months). Buccal soft tissue volume was measured at 1, 3, and 5 mm apical to the healing abutment position and a comparison between T0 and T1 was performed. Student t-test was used according to the distribution of the data (Shapiro-Wilk).

RESULTS

The mean KT width at baseline was 4.54 ± 1.31 mm at buccal side and 5.04 ± 1.88 mm at lingual side. After 3 months, the mean KM values were 3.15 ± 1.03 mm and 3.72 ± 1.56 mm at the buccal and lingual aspects, respectively. The differences, 30.6% of KM reduction buccally and 26.1% of reduction lingually, were statistically significant for both sides.

CONCLUSIONS

Within the limitations of this investigation, it was observed that the KM width from the baseline to the 3 months follow up presented a significant dimensional change in both the buccal and lingual aspects, whereas buccal soft tissue volume showed an increase between baseline and follow up.

Prevalence and risk indicators of midfacial peri-implant soft tissue dehiscence at single site in the esthetic zone: A cross-sectional clinical and ultrasonographic study

BACKGROUND

Esthetic complications of dental implants in the esthetic zone can have a major negative impact on patients' quality of life and perception of implant therapy. The aim of the present study was to evaluate the prevalence of peri-implant soft tissue dehiscence (PSTD) and the clinical and ultrasonographic risk indicators for this condition.

METHODS

Subjects with one or more healthy single dental implants in the esthetic area were identified and recruited. Clinical and ultrasonographic measurements, including PSTD class and subclass, pocket depth, keratinized mucosa width (KMW), mucosal thickness (MT) at 1 mm and 3 mm, buccal bone distance (BBD) and buccal bone thickness, were evaluated in healthy implants and implants with PSTD.

RESULTS

153 subjects with a total of 176 dental implants were included. The prevalence of PSTD was 54.2% and 56.8% on a patient and implant level, respectively. The most frequent type of PSTD was the one characterized by having both an implant-supported crown longer than the clinical crown of the homologous tooth and a visible abutment/implant fixture exposed to the oral cavity. The multi-variate analysis showed that the presence of an adjacent implant, a longer time of the implant in function, limited MT, reduced KMW and increased BBD were significantly associated with the presence of a PSTD.

CONCLUSIONS

PSTDs are common findings in the esthetic region. Several risk indicators for this condition, such as presence of an adjacent implant, increased time in function of the implant, higher BBD, lower KMW and MT were identified. This article is protected by copyright. All rights reserved.

Laterally rotated flap for soft tissue augmentation around maxillary loaded osseointegrated dental implants: preliminary results of a pilot study

A minimal width and thickness of keratinized and attached soft tissue is desirable to prevent peri-implant diseases. This report describes the preliminary results of a pilot study of a surgical approach for soft tissue augmentation around loaded dental implants in the partially or totally edentulous maxilla. Four patients presenting eight maxillary implants with a buccal peri-implant soft tissue deficiency received a laterally rotated flap. A buccal mesial and apical recipient area was created around each implant, and a pediculated keratinized graft was rotated 90° from the distopalatal and positioned and sutured on the peri-implant buccal aspect. All implants treated showed a gain in buccal clinical peri-implant attachment (1.37 ± 0.44 mm) and buccal soft tissue levels (2.06 ± 1.40 mm) and interproximal soft tissue levels (1 ± 0.75 mm). The technique provided quality soft tissue with a gain in soft tissue thickness (3.06 ± 0.68 mm) and keratinized wide tissue (4.69 ± 0.80 mm) with minimal morbidity (1575 ± 549.67 mg of ibuprofen) and maintenance of prosthetic loading. Peri-implant soft tissue stability was maintained for 13.5 ± 1.87 months. Laterally rotated flap can be applied and provide clinical benefits to compromised implants due to the presence of buccal peri-implant soft tissue deficiency. Further studies are required to confirm these preliminary results.

Biomaterials for Periodontal and Peri-Implant Regeneration

Periodontal and peri-implant regeneration is the technique that aims to restore the damaged tissue around teeth and implants. They are surrounded by a different apparatus, and according to it, the regenerative procedure can differ for both sites. During the last century, several biomaterials and biological mediators were proposed to achieve a complete restoration of the damaged tissues with less invasiveness and a tailored approach. Based on relevant systematic reviews and articles searched on PubMed, Scopus, and Cochrane databases, data regarding different biomaterials were extracted and summarized. Bone grafts of different origin, membranes for guided tissue regeneration, growth factors, and stem cells are currently the foundation of the routinary clinical practice. Moreover, a tailored approach, according to the patient and specific to the involved tooth or implant, is mandatory to achieve a better result and a reduction in patient morbidity and discomfort. The aim of this review is to summarize clinical findings and future developments regarding grafts, membranes, molecules, and emerging therapies. In conclusion, tissue engineering is constantly evolving; moreover, a tailor-made approach for each patient is essential to obtain a reliable result and the combination of several biomaterials is the elective choice in several conditions.