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

Immediate Placement and Restoration of a New Tapered Implant System in the Aesthetic Region: A Report of Three Cases

Objective

To assess the clinical, radiographic, aesthetic, and patient-centred outcomes of a new implant system applied for an immediate implant placement and restoration approach in single tooth replacement of anterior maxillary teeth. Material and Method. Three cases were treated with a bone level tapered implant. All patients were treated with the same strategy involving flapless extraction and implant placement with simultaneous augmentation. Implants were provisionally restored with a screw-retained restoration at the day of surgery. Definitive restoration was fabricated after 3 months. Follow-up was one year after definitive restoration.

Results

At the 1-year follow-up, the implants were stable and no complications had occurred. Peri-implant bone levels had increased with a mean value of 0.24 ± 0.30 mm between definitive restoration placement and 1 year of follow-up. Clinical outcome scores showed healthy soft tissues. Mean Pink and White Esthetic scores were rated 7.0 and 7.3, respectively. Mean patient satisfaction had improved from 55.7 (pretreatment) to 90.0 (1-year follow-up) on a 0-100 VAS scale.

Conclusion

Immediate implant placement and restoration with the new tapered bone level implant system are accompanied by good initial clinical and radiographic results as well as high patient satisfaction.

Peri-implant soft tissue phenotype modification and its impact on peri-implant health: A systematic review and network meta-analysis

BACKGROUND

The peri-implant soft tissue phenotype (PSP) encompasses the keratinized mucosa width (KMW), mucosal thickness (MT), and supracrestal tissue height (STH). Numerous approaches to augment soft tissue volume around endosseous dental implants have been investigated. To what extent PSP modification is beneficial for peri-implant health has been subject of debate in the field of implant dentistry. The aim of this systematic review was to analyze the evidence regarding the efficacy of soft tissue augmentation procedures aimed at modifying the PSP and their impact on peri-implant health.

METHODS

A comprehensive search was performed to identify clinical studies that involved soft tissue augmentation around dental implants and reported findings on KMW, MT, and/or STH changes. The effect of the intervention on peri-implant health was also assessed. Selected articles were classified based on the general type of surgical approach to increase PSP, either bilaminar or an apically positioned flap (APF) technique. A network meta-analysis including only randomized-controlled trials (RCTs) reporting on PSP outcomes was conducted to assess and compare different techniques.

RESULTS

A total of 52 articles were included in the qualitative analysis, and 23 RCTs were included as part of the network meta-analysis. Sixteen RCTs reported the outcomes of PSP modification therapy with bilaminar techniques, whereas 7 involved the use of APF. The analysis showed that bilaminar techniques in combination with soft tissue grafts (connective tissue graft [CTG], collagen matrix [CM], and acellular dermal matrix [ADM]) resulted in a significant increase in MT compared to non-augmented sites. In particular, CTG and ADM were associated with higher MT gain as compared to CM and non-augmented sites. However, no significant differences in KMW were observed across different bilaminar techniques. PSP modification via a bilaminar approach utilizing either CTG or CM showed beneficial effects on marginal bone level stability. APF-based approaches in combination with free gingival graft (FGG), CTG, CM, or ADM showed a significant KMW gain compared to non-augmented sites. However, compared to APF alone, only FGG exhibited a significantly higher KMW gain. APF with any evaluated soft tissue graft was associated with with reduction of probing depth, soft tissue dehiscence and plaque index compared to non-augmented sites compared to non-augmented sites. The evidence regarding the effect of PSP modification via APF-based approaches on peri-implant marginal bone loss or preservation is inconclusive.

CONCLUSIONS

Bilaminar approach involving CTG or ADM obtained the highest amount of MT gain, whereas APF in combination with FGG was the most effective technique for increasing KMW. KMW augmentation via APF was associated with a significant reduction in probing depth, soft tissue dehiscence and plaque index, regardless of the soft tissue grafting material employed, whereas bilaminar techniques with CTG or CM showed beneficial effects on marginal bone level stability.

Immediate implant placement in molar extraction sites: a 1-year prospective case series pilot study

Background

There is a growing tendency to place single tooth implants immediately after extracting a failing tooth in the posterior region. The aim of this prospective case series pilot study was to evaluate immediate implant placement in molar post-extraction sites during a 1-year follow-up period.

Materials and methods

Fifteen consecutive patients with a single failing molar in the maxilla or mandible, and presenting enough bone to expect primary implant stability and an implant site free of infection, were included. The implants, with a large thread depth and sharp thread edges, were placed in each patient according to a two-staged surgical procedure. Three months later, a full contour screw-retained zirconia restoration with an angulated screw channel abutment was provided. Clinical and radiographic examinations were performed 1 month and 12 months after placing the restoration. In addition, the patients’ satisfaction with the restoration was scored after 12 months.

Results

Four out of 15 of the mobile implants had to be removed before the 1-year evaluation. The implant and restoration survival rates were 73.3% at the 1-year evaluation (n = 15). The mean marginal bone loss, from loading to the 12-month follow-up, was 0.17 mm (n = 11). The mean plaque, calculus, peri-implant mucosa, bleeding, and pocket probing depth scores were low, depicting healthy peri-implant conditions. The patients were very satisfied.

Conclusion

It was demonstrated, within the limitations of this study, that immediate placement of regular diameter implants in molar post-extraction sites in the maxilla and mandible resulted in a high implant failure rate during a 1-year follow-up period.

Trial registration

Netherlands Trial Register, NL8117. Registered 24 October 2019 - Retrospectively registered, https://www.trialregister.nl/trial/8117.

Immediate implant placement and provisionalization: Aesthetic outcome 1 year after implant placement. A prospective clinical multicenter study

BACKGROUND

Prospective aesthetic outcomes on a high number of patients after immediate implant placement and provisionalization (IIPP) are lacking.

PURPOSE

To analyze the aesthetic outcome after IIPP.

MATERIALS AND METHODS

One hundred consecutive patients with a failing maxillary incisor were provided with an immediately placed and provisionalized nonloaded implant using a flapless procedure and palatal implant positioning. The remaining gap buccally was filled with a bone substitute. Preoperatively (T0), 2 weeks postoperatively (T1), direct after placement of the permanent crown (T2), and 1 year after IIPP (T3), standardized light photographs were made. Change in aesthetic score was the primary outcome measure. Both the white aesthetic score (WES) and pink aesthetic score (PES) were used.

RESULTS

In the first year postsurgery, the mean total-WES and total-PES scores raised from 4.5 to 8.2, and from 9.9 to 12.1, respectively. The mean PES scores for mesial and distal papilla, soft tissue marginal level, contour, color, and texture, raised significantly (P < .05), while the alveolar process contour, on average, remained stable from T0 to T3.

CONCLUSIONS

Within the limitations of this 1-year research, it may be concluded that, following this minimal invasive IIPP procedure, a high aesthetic outcome was achieved.

The effectiveness of immediate implant placement for single tooth replacement compared to delayed implant placement: A systematic review and meta-analysis

AIM

To compare immediate implant placement (IIP) to delayed single implant placement (DIP, ≥3 months post-extraction) in terms of implant survival (primary outcome), surgical, clinical, aesthetic, radiographic and patient-reported outcomes (secondary outcomes).

MATERIALS AND METHODS

Two reviewers independently performed an electronic search in PubMed, Web of Science, EMBASE and Cochrane and a hand search to identify eligible studies up to May 2018. Only randomized controlled trials (RCTs) and non-randomized controlled studies (NRSs) comparing IIP to DIP with at least 1 year of follow-up were selected for a qualitative analysis and meta-analysis.

RESULTS

The search identified 3 RCTs and 5 NRSs out of 2,589 titles providing data on 473 single implants (IIP: 233, DIP: 240) that had been in function between 12 and 96 months. One RCT showed unclear risk of bias, whereas all other studies demonstrated high risk. Meta-analysis showed significantly lower implant survival for IIP (94.9%) as compared to DIP (98.9%) (RR 0.96, 95% CI [0.93; 0.99], p = 0.02). All were early implant failures. A subgroup meta-analysis demonstrated a trend towards lower implant survival for IIP when postoperative antibiotics had not been administered (RR: 0.93, 95% CI [0.86; 1.00], p = 0.07). This was not observed among studies including the administration of postoperative antibiotics (RR: 0.98, 95% CI [0.94; 1.02], p = 0.35). Meta-analyses showed similar probing depth (WMD 0.43 mm, 95% CI [-0.47; 1.33], p = 0.35) and aesthetic outcomes as assessed by the pink aesthetic score (standardized WMD -0.03, 95% CI [-0.46; 0.39], p = 0.88) for IIP and DIP. Data on marginal bone loss were conflicting and highly biased. Soft tissue recession was underreported and available data were highly biased. Patient-reported outcomes were underreported, yet both IIP and DIP seemed well tolerated.

CONCLUSION

Immediate implant placement demonstrated higher risk for early implant loss than DIP. There is a need for RCTs comparing IIP to DIP with CBCT analyses at different time points and data on midfacial recession with the preoperative status as baseline. In these studies, the need for hard and soft tissue grafting should also be evaluated.

Flapless immediate implant placement and provisionalization in periodontal patients: A retrospective consecutive case-series study of single-tooth sites with dehiscence-type osseous defects

OBJECTIVE

To assess the clinical outcomes of flapless, immediate implant placement with simultaneous augmentation of dehiscence defects and immediate provisional restoration.

MATERIALS AND METHODS

Retrospective evaluation of 40 periodontal patients who received a flapless immediate implant for single-tooth replacement with simultaneous augmentation of dehiscence defects and immediate provisional restoration, at follow-up periods ranging from 1 year minimum to 7 years maximum. Dehiscence defects were augmented using autogenous bone grafts and/or deproteinized bovine bone mineral, and autogenous or allogeneic connective tissue grafts. The following aspects were evaluated: clinical success (Clinical Oral Implants Research, 8, 1997, 161), crestal bone loss (calibrated digital periapical X-rays) and aesthetics (Pink Esthetic Score, PES). Additionally, a questionnaire was devised to obtain patient's subjective evaluation.

RESULTS

A 98.3% (95% CI: 91%-99%) success rate was observed. At 8 weeks, mean bone loss was 0.47 mm (n = 39); between 8 weeks and 1 year, this va lue attained 0.24 mm and between years 1 and 5 years 0.06 mm (n = 9). The evaluated PES in 37 single-tooth implants was 12.4, with PES = 7 (aesthetic failures) in two cases, and aesthetic outcomes were excellent (PES ≥ 12) in 29 cases (78.4%). When compared with the contralateral tooth, a recession under 1 mm was observed in 78% of cases. The patient's subjective satisfaction value ranged from 98% to 100%.

CONCLUSION

This type of minimally invasive treatment of alveoli with buccal plate deficiencies delivers, in the hands of an experienced clinician, a high clinical and aesthetic success percentage being rated by patients as satisfactory. Clinicians should be aware that 1-2 mm comparative recession could be observed.

Autogenous soft tissue grafting for periodontal and peri-implant plastic surgical reconstruction

This state-of-the-art review presents the latest evidence and the current status of autogenous soft tissue grafting for soft tissue augmentation and recession coverage at teeth and dental implant sites. The indications and predictability of the free gingival graft and connective tissue graft (CTG) techniques are highlighted, together with their expected clinical and esthetic outcomes. CTGs can be harvested from the maxillary tuberosity or from palate with different approaches that can have an impact on graft quality and patient morbidity. The influence of CTGs on soft tissue thickness and keratinized tissue width are also discussed.

Annual review of selected scientific literature: A report of the Committee on Scientific Investigation of the American Academy of Restorative Dentistry

This comprehensive review of the 2018 dental literature is provided to inform busy dentists about progress in the profession. Developed by the Committee on Scientific Investigation of the American Academy of Restorative Dentistry, each author brings discipline-specific expertise to one of the 8 sections of the report including (1) prosthodontics; (2) periodontics, alveolar bone, and peri-implant tissues; (3) implant dentistry; (4) dental materials and therapeutics; (5) occlusion and temporomandibular disorders; (6) sleep-related breathing disorders; (7) oral medicine and oral and maxillofacial surgery; and (8) dental caries and cariology. The report targets important information that will likely influence day-to-day treatment decisions. Each review is not intended to stand alone but to update interested readers so that they may visit source materials if greater detail is desired. As the profession continues its march toward evidence-based clinical decision-making, an already voluminous library of potentially valuable dental literature continues to grow. It is the intention of this review and its authors to provide assistance in navigating the extensive dental literature published in 2018. It is our hope that readers find this work useful in the clinical management of patients moving forward.

The effects of hard and soft tissue grafting and individualization of healing abutments at immediate implants: an experimental study in dogs

Purpose

To evaluate the effects of intra-alveolar socket grafting, subepithelial connective tissue grafts, and individualized abutments on peri-implant hard and soft tissue outcomes following immediate implant placement.

Methods

This randomized experimental study employed 5 mongrel dogs, with 4 sites per dog (total of 20 sites). The mesial roots of P3 and P4 were extracted in each hemimandible and immediate dental implants were placed. Each site was randomly assigned to 1 of 4 different treatment groups: standardized healing abutment (control group), alloplastic bone substitute material (BSS) + standardized healing abutment (SA group), BSS + individualized healing abutment (IA group), and BSS + individualized healing abutment + a subepithelial connective tissue graft (IAG group). Clinical, histological, and profilometric analyses were performed. The intergroup differences were calculated using the Bonferroni test, setting statistical significance at P<0.05.

Results

Clinically, the control and SA groups demonstrated a coronal shift in the buccal height of the mucosa (0.88±0.48 mm and 0.37±1.1 mm, respectively). The IA and IAG groups exhibited an apical shift of the mucosa (−0.7±1.15 mm and −1.1±0.96 mm, respectively). Histologically, the SA and control groups demonstrated marginal mucosa heights of 4.1±0.28 mm and 4.0±0.53 mm relative to the implant shoulder, respectively. The IA and IAG groups, in contrast, only showed a height of 2.6 mm. In addition, the height of the mucosa in relation to the most coronal buccal bone crest or bone substitute particles was not significantly different among the groups. Volumetrically, the IA group (−0.73±0.46 mm) lost less volume on the buccal side than the control (−0.93±0.44 mm), SA (−0.97±0.73 mm), and IAG (−0.88±0.45 mm) groups.

Conclusions

The control group demonstrated the most favorable change of height of the margo mucosae and the largest dimensions of the peri-implant soft tissues. However, the addition of a bone substitute material and an individualized healing abutment resulted in slightly better preservation of the peri-implant soft tissue contour.

Accuracy of Customized Prefabricated Screw-Type Immediate Provisional Restorations after Single-Implant Placement

Limited evidence is available comparing the differences between pre-operative and post-operative 3D implant positions from the viewpoint of prosthetics. We aimed to investigate the differences between preplanned positions of virtual provisional restorations and their actual positions following fully guided single-implant placement. Ten maxillary typodonts with missing right central incisors were imaged using cone-beam computed tomography, and digital impressions were obtained using an intraoral scanner. These data were imported into implant-planning software, following which the provisional restorations were designed. After data superimposition, an appropriate implant position was determined, and a computer-assisted implant surgical guide was designed for each typodont. Orders generated from the implant-planning software were imported into relevant computer-aided design software to design the custom abutments. The abutments, provisional restorations, and surgical guides were fabricated, and each restoration was cemented to the corresponding abutments, generating a screw-type immediate provisional restoration. The implants were placed using the surgical guides, and the screw-type provisional restorations were engaged to the implants. The typodonts were then rescanned using the intraoral scanner. The restorations designed at the treatment planning stage were compared with those in the post-operative scan using metrology software. The angular deviation around the central axis of the implant was measured, and the differences in the crown position were converted to root mean square (RMS) values. The post-operative provisional restorations exhibited an absolute angular deviation of 6.94 ± 5.78° and an RMS value of 85.8 ± 20.2 µm when compared with their positions in the pre-operative stage. Within the limitations of the present in vitro study, the results highlight the potential application of customized prefabricated immediate provisional restorations after single-implant placement.

[Immediate implantation following tooth extraction in fresh maxillary molar socket with poor bone quality]

OBJECTIVE

To explore the feasibility of immediate implantation after tooth extraction in the maxillary molar socket with poor bone quality beneath the sinus.

METHODS

We collected the data from the patients undergoing extraction of maxillary molars with poor bone quality between the sockets and sinuses. Sinus lifting and immediate implant following the extraction were performed simultaneously in these cases, and the primary stability of the implants, wound healing, and changes of the sinus were observed. At 6 months after the operations, the crowns were installed on the implants. The masticatory function was observed, and the growth of the alveolar bones and their changes after the operations were examined using microcomputed tomography (MCT).

RESULTS

We analyzed 32 extraction cases with immediate implantation in the maxillary molar sockets with poor bone quality beneath the sinus. The average age of the patients was 59.8 years, and the length and diameter of the implant ranged from 8.5 to 10 mm and from 4.5 to 5.5 mm, respectively. The torque force of the implants varied from the minimum (in which cases the implants remained fixed after insertion with fingers) to the maximum of 30 N·cm. The postoperative recovery was uneventful in all the cases and no failed or movable implants were found. At 6 months after the operation, none of the patients showed abnormalities in the sinus, and in all the cases the crowns were successfully installed on the implants with good recovery of the masticatory functions. Follow-up of the patients for 12 to 96 months after the operation showed successful immediate implantation in all the cases. After the operation, the changes of the mean alveolar ridge heights on the buccal, palatal, mesial, and distal sides of the patients were 0.8069±0.6253 mm (t=1.2904, P&gt;0.1), 0.5272± 0.3331 mm (t=1.5836, P&gt;0.05), 0.5416±0.4048 mm (t=1.3379, P&gt;0.05), and 0.5172±0.3874 mm (t=1.3351, P&gt;0.05), respectively; the change of the alveolar ridge width was 0.5522±0.4381 mm (t=1.2604, P&gt;0.1) mm. The dimension of the alveolar bone underwent no significant changes after the operation in these patients.

CONCLUSIONS

Immediate implantation in the maxillary extraction socket with a poor bone quality can avoid damages to the sinus and achieve good outcomes with such advantages of less trauma, full use of the innate gingiva and alveolar ridge, and well preserved morphology of the alveolar ridge as compared with delayed implantation.

Influence of soft tissue grafting, orofacial implant position, and angulation on facial hard and soft tissue thickness at immediately inserted and provisionalized implants in the anterior maxilla

BACKGROUND

Resorption of hard and soft tissues following immediate implant insertion is frequently reported. Data regarding the influencing factors on facial tissue thickness are rare.

PURPOSE

This retrospective study investigated the impact of connective tissue grafting, the orofacial angulation and position of immediately inserted and provisionalized implants on the facial hard and soft tissue thickness in the anterior maxilla within a 1- to 5-year follow-up.

MATERIAL AND METHODS

Implants with the prerequisite of having preoperative and postoperative cone beam computed tomography (CBCT) and a follow-up of 1 to 5 years were included. Facial bone deficiencies were grafted flaplessly with autogenous bone in all sites. In a subgroup of implants additional connective tissue grafting was performed, whereas the remaining implants were not grafted with soft tissue. The orofacial tooth and implant angulation, the change of horizontal position and the facial bone thickness were measured by CBCT, the facial mucosa thickness by an ultrasonic device.

RESULTS

In total, 76 implants were placed in 55 patients. Sixty-nine sites showed a facial bone defect. Thirty-eight received a connective tissue graft additionally. All implants were still in function after a mean follow-up of 36 months. The mean thickness of the facial mucosa was 1.72 mm at 1 mm, 1.63 mm at 4 mm, 1.52 mm at 6 mm, and 1.66 mm at 9 mm apically to mucosal margin. The bone thickness was 0.02, 0.25, and 0.36 mm initially and 1.32, 1.26, and 1.11 mm finally at 1, 3, and 6 mm apically to implant shoulder level. Mixed model analysis revealed an impact of the preoperative bone status on the facial bone increase. The facial soft tissue thickness was significantly influenced by the gingival biotype.

CONCLUSIONS

The results indicate that an initial severe hard tissue defect allows for significant bone regeneration. The facial soft tissue thickness is primarily influenced by the gingival biotype.

Impact of timing on soft tissue augmentation during implant treatment: A systematic review and meta-analysis

BACKGROUND

To achieve a predictable esthetic and functional outcome, soft tissue augmentation has become popular in implant treatment.

OBJECTIVES

The aim of this systematic review and meta-analysis was to assess the influence of different timing for soft tissue augmentation during implant treatment on soft tissue conditions and its stability.

MATERIAL AND METHODS

Electronic and manual searches for articles written in English up to September 2017 were performed by two independent reviewers. Human clinical studies with the purpose of evaluating outcomes (at least 3-month follow-up) of autogenous soft tissue graft for augmentation during implant treatment, either simultaneous or after implant placement (staged), were included. Cumulative changes of keratinized tissue width (KTW), soft tissue thickness (STT), and mid-buccal mucosal recession (MR) data were analyzed with a random-effects model to compare the postoperative outcomes.

RESULTS

Twenty-nine human studies (eight randomized clinical trials, six cohort studies, and 15 case series) that met the inclusion criteria were included. For the overall data, the weighted mean STT gain (1 year after surgery) was 1.03 mm (95% CI: 0.78-1.29 mm), among which the simultaneous group was 1.12 mm (95% CI: 0.75-1.49 mm) and staged group (3-6 months after implant placement) was 0.95 mm (95% CI: 0.58-1.31 mm). There was no statistically significant difference in KTW and MR between 3 months and more than 3 months after surgery.

CONCLUSIONS

This review revealed that the stability of soft tissue, in terms of KTW and mid-buccal MR, can be obtained 3 months after surgery. There is no difference between simultaneous and staged soft tissue augmentation during implant treatment, and both procedures significantly enhance KTW and STT.