Influence of immediate/delayed implant placement and implant platform on the peri-implant bone formation

A randomized controlled trial of immediate implant placement comparing hydroxyapatite nano-coated and uncoated sandblasted/acid-etched implants using a digital surgical guide

PURPOSE

This study evaluated the implant stability, volumetric changes, and patient-reported outcome measures (PROMs) of hydroxyapatite (HA) nano-coated sandblasted/acid-etched (SLA) implants compared to uncoated SLA implants.

METHODS

Forty patients were recruited and randomly allocated to HA nano-coated SLA group (test, n = 20) and uncoated SLA group (control, n = 20) using single-blinded/block randomization. Implants were immediately placed in maxillary posterior region using a digital surgical guide. Insertion torque and implant stability quotient (ISQ) were measured at implant surgery and 1, 2, 3, and 4 months postoperatively. Intraoral scans, PROMs and soft tissue inflammation data were collected, and multivariable linear regression analysis of ISQ was performed.

RESULTS

In total, 48 implants (test; n = 24, control; n = 24) in 37 patients (test; n = 19, control; n = 18) were analyzed. Despite no significant between-group difference at surgery, the test group showed higher ISQ values than the control group at 2 (76.53 ± 4.17 vs. 71.32 ± 4.79, p < 0.01), 3 (77.45 ± 4.41 vs. 73.85 ± 4.69, p < 0.05), and 4 months (79.08 ± 2.96 vs. 73.43 ± 3.52, p < 0.0001) postoperatively. There were no significant differences in linear and volumetric changes, PROMs, and soft tissue inflammation analysis between two groups. The ISQ at implant surgery was influenced by age and diabetes mellitus (DM) at the implant level and DM and predicted total bone-to-implant contact area at the patient level.

CONCLUSION

HA nano-coated SLA implants promoted favorable immediate implants stability during early osseointegration phase compared to uncoated SLA implants, but displayed similar dimensional changes, PROMs, and soft tissue inflammation outcomes.

TRIAL REGISTRATION

Clinical Research Information Service (CRIS), KCT0006364. Registered 21 July 2021, https://cris.nih.go.kr/cris/search/detailSearch.do?seq=24221&search_page=L .

Comparing Dual-Zone Immediate Implant Placement and Socket Shield Technique for Ridge Width Changes in the Maxilla: A Prospective Cohort Study

PURPOSE

The aim of this prospective cohort study was to assess the facial-palatal ridge dimensional changes that occurred at 8-10 months following flapless dual-zone (DZ) immediate implant placement and socket-shield (SS) immediate placement in the maxilla.

MATERIALS AND METHODS

A total of 19 patients who received 20 implants were included, with 10 implants (MegaGen AnyRidge) placed for each treatment, DZ and SS. Cast models were made at 8-10 months after implant placement to assess the dimensional ridge changes by measuring the facial-palatal ridge width on implant sites (T) at six designated points starting from the gingival margin (0, 1, 2, 3, 5 and 7) and comparing it with the corresponding measurement on the contralateral tooth site (C).

RESULTS

All 20 implants demonstrated successful osseointegration at 8-10 months follow-up (survival rate 100%). Two out of ten cases of SS group presented with minor manageable complications of external shield exposure. DZ group showed an average of 0.3 mm facial-palatal ridge width reduction, while SS group revealed a mean gain in ridge width of approximately 0.2 mm at 8-10 months follow-up.

CONCLUSION

When comparing between two treatments, there was a significant difference in ridge width change at 8-10 months following implant placement, indicating better preservation of the ridge contour for socket shield technique.

Immediate implant placement with socket shield technique in the maxilla: a prospective case series evaluation at 1-year follow-up

Background

The aims of this case series were to investigate the clinical, radiographic, implant success, complication incidence, esthetic, and patient-reported outcomes of 10 immediately placed implants associated with the socket shield technique at 12 months post-loading and to assess the ridge width changes that occurred at 8 months following implant placement.

Methods

A total of 10 patients received 10 socket shield immediate implants (MegaGen AnyRidge). At 8 months postimplantation, casts were made to assess the ridge width changes by measuring the ridge width at the implant sites and comparing them with the corresponding measurements at the contralateral tooth site. At 12 months post-loading, clinical indices, marginal bone loss, pink esthetic score, and patient-assessed outcomes were evaluated. The mean, standard deviation and median were calculated for all continuous variables.

Results

All implants demonstrated a 100% success rate, while 2 implants presented with external shield exposure that was managed successfully. The mean marginal bone loss was 0.08 ± 0.14 mm mesially and 0.21 ± 0.23 mm distally. Esthetic evaluation yielded an average modified pink esthetic score of 8.65. A mean gain of 0.17 mm in the facial-palatal ridge width was recorded at 8 months postimplantation.

Conclusions

The socket shield technique enhanced the functional and esthetic results by preserving the alveolar bone and peri-implant soft tissues. However, this is a sensitive technique and still needs more robust evidence before it can be recommended for everyday clinical practice.

A Multidisciplinary Approach to Congenitally Missing Central Incisors: A Case Report

Hypodontia is one of the most common developmental problems of human dentition. The treatment of missing maxillary central incisors is always a challenging task, often requiring a multidisciplinary approach. This case report describes such a multidisciplinary approach for a female patient with congenitally missing maxillary central incisors and class II division 1 occlusion. Significant horizontal overlap was present with class II division 1 occlusion in a patient with a history of cleft palate. Implant therapy was thereby not an option. Orthodontic treatment was provided to decrease the horizontal overlap and reposition the teeth. Esthetic crown lengthening was performed and monolithic lithium disilicate crowns were placed. Critical analysis of the treatment plan through cooperation among specialists is required to obtain the ideal result. Orthodontic treatment may be necessary to close or gain more space, followed by implant placement (if acceptable), and restorative treatment. It is important to create the treatment plan through a multidisciplinary approach involving orthodontists, surgeons, and restorative specialists before initiating treatment.

Pre-Clinical Models in Implant Dentistry: Past, Present, Future

Biomedical research seeks to generate experimental results for translation to clinical settings. In order to improve the transition from bench to bedside, researchers must draw justifiable conclusions based on data from an appropriate model. Animal testing, as a prerequisite to human clinical exposure, is performed in a range of species, from laboratory mice to larger animals (such as dogs or non-human primates). Minipigs appear to be the animal of choice for studying bone surgery around intraoral dental implants. Dog models, well-known in the field of dental implant research, tend now to be used for studies conducted under compromised oral conditions (biofilm). Regarding small animal models, research studies mostly use rodents, with interest in rabbit models declining. Mouse models remain a reference for genetic studies. On the other hand, over the last decade, scientific advances and government guidelines have led to the replacement, reduction, and refinement of the use of all animal models in dental implant research. In new development strategies, some in vivo experiments are being progressively replaced by in vitro or biomaterial approaches. In this review, we summarize the key information on the animal models currently available for dental implant research and highlight (i) the pros and cons of each type, (ii) new levels of decisional procedures regarding study objectives, and (iii) the outlook for animal research, discussing possible non-animal options.

Esthetic and functional rehabilitation of bilateral congenital absence of maxillary lateral incisors: Minimally invasive surgical and prosthetic approach

OBJECTIVE

Congenital absence of maxillary lateral incisors is a frequent clinical challenge which must be solved by a multidisciplinary approach in order to obtain an esthetic and functional restorative treatment. Noninvasive treatments, that are in accordance with the patients' expectations, should be the first therapeutic alternative. If the deciduous tooth is present, minimally invasive dental extraction followed by immediate dental implant placement and provisional restoration is indicated. In this restorative treatment, an adequate emergency profile can be achieved by peri-implant soft-tissue-conditioning techniques. Moreover, the association of restorative materials, such as composite resins and dental ceramics, provides more predictable esthetic results.

CLINICAL CONSIDERATIONS

The present case report presents a rehabilitation of bilateral congenital absence of maxillary lateral incisors through a multidisciplinary approach. Dental implants, long-term provisional restoration, tooth bleaching, minimally veneered high-translucent monolithic zirconia crowns, feldspathic veneers, and composite restorations were used by the dental team to achieve the expected functional and esthetic outcomes.

CONCLUSIONS

Different treatment modalities are available for the rehabilitation of congenital absence of teeth. However, it is important that a dental team consider performing minimally invasive treatments, as many of these treatments are done on young patients.

CLINICAL SIGNIFICANCE

Patient-centered treatments involving minimally invasive approaches in a multidisciplinary environment would be appropriate in order to achieve predictable results.

A novel methodological approach using superimposed Micro-CT and STL images to analyze hard and soft tissue volume in immediate and delayed implants with different cervical designs

OBJECTIVES

To study the hard and soft tissue volume after placing immediate (IMI) or delayed implants (DLI) with a triangular coronal macro-design (Test/T) or a conventional cylindrical design (Control/C).

MATERIAL AND METHODS

T/C implants were inserted in healed ridges or in fresh extraction sockets of eight beagle dogs. Biopsies were processed for Micro-CT analysis and dental stone casts were optically scanned to obtain STL files revealing the soft tissue contours at 12 weeks. Image analysis software was utilized to match common landmarks superimposing the two sets of data. Three distinct volumes were calculated; buccal bone volume (B-BV), soft tissue volume below the implant shoulder (EC-STV), and the soft tissue volume above the implant shoulder (SC-STV). Using linear measurements, the soft tissue height (STH), the mucosal thickness (MT-IS), and the distance from the implant shoulder to the bone crest (I-BC) were assessed in the digital images and in conventional histology to assess the concordance, reproducibility, and reliability.

RESULTS

There were no significant differences between test and control implants regarding the buccal bone volume, although test implants had greater B-BV in all locations except for PM2. The soft tissue volume was similar at T/C implants. The surgical approach influenced the distribution of the total tissue volume. In the IMI, a low position of the bone crest was correlated with low values of B-BV, SC-STV, MT-IS, and STH. Linear measurements showed a high correlation between the histology and digital measurements and high inter and intra examiner agreement.

CONCLUSION

The superimposition of Micro-CT/STL allowed the analysis of soft and hard tissue volumes. Reduction of the implant buccal aspect resulted in nonsignificant higher bone volume although similar soft tissue volume while the surgical approach influenced soft tissue response.