Narrow diameter implants to replace congenital missing maxillary lateral incisors: a 1-year prospective, controlled, clinical study

Clinical and radiographic outcomes of implant-supported fixed prostheses with cantilever extension in anterior mandible: A retrospective study

OBJECTIVES

The objective of this study is to analyze the clinical and radiographic outcomes of implant-supported fixed protheses with cantilever extensions (ISFPCs) in the partially edentulous anterior mandible.

MATERIALS AND METHODS

Patients who received anterior mandible implant restoration between January 2016 and December 2021 were included. Patients with two, three, or four continuous missing teeth receiving adjacent implant supported single-unit crowns (ISSCs), ISFPCs, implant-supported fixed protheses without cantilever extensions (ISFPNs) were divided into groups: ISSC+ISSC, ISFPC, ISSC+ISFPC, three-unit ISFPN, ISFPC+ISFPC, or four-unit ISFPN, respectively. We recorded and evaluated survival rates, mechanical and biological complications, peri-implant marginal bone loss (MBL), esthetic outcomes, and patient perceptions. Statistical analysis was performed using linear mixed models (LMM).

RESULTS

The study included 87 patients and 152 implants. No implant loss occurred during an average follow-up of 3.48 ± 1.85 years (range: 1-7 years). According to LMM models, prosthetic type had a statistically significant impact on MBL during follow-up periods, in favor of the ISFPC and ISFPC+ISFPC groups (0.16 ± 0.48 mm vs. 0.51 ± 0.49 mm, p = .034; 0.22 ± 0.49 mm vs. 0.60 ± 0.62 mm, p = .043, respectively). Mechanical and biological complications were relatively low and comparable. The four-unit ISFPC group had higher subjective esthetic scores compared with the ISSC+ISSC group (98.6 vs. 83.8, p < .05), and patients in the ISFPC+ISFPC group expressed greater satisfaction with cleanability than the ISFPN group (98.8 vs. 80.6).

CONCLUSION

ISFPCs offer a highly predictable treatment option in the anterior mandible, characterized by high survival rates, and comparable complication rates, peri-implant bone stability and esthetics to adjacent ISSCs or ISFPNs.

Improved new bone formation capacity of hyaluronic acid-bone substitute compound in rat calvarial critical size defect

BACKGROUND

Bone loss of residual alveolar ridges is a great challenge in the field of dental implantology. Deproteinized bovine bone mineral (DBBM) is commonly used for bone regeneration, however, it is loose and difficult to handle in clinical practice. Hyaluronic acid (HA) shows viscoelasticity, permeability and excellent biocompatibility. The aim of this study is to evaluate whether high-molecular-weight (MW) HA combined with DBBM could promote new bone formation in rat calvarial critical size defects (CSDs).

MATERIALS AND METHODS

Rat calvarial CSDs (5 mm in diameter) were created. Rats (n = 45) were randomly divided into 3 groups: HA-DBBM compound grafting group, DBBM particles only grafting group and no graft group. Defect healing was assessed by hematoxylin-eosin staining and histomorphometry 2, 4 and 8 weeks postop, followed by Micro-CT scanning 8 weeks postop. Statistical analyses were performed by ANOVA followed by Tukey's post hoc test with P < 0.05 indicating statistical significance.

RESULTS

All rats survived after surgery. Histomorphometric evaluation revealed that at 2, 4 and 8 weeks postop, the percentage of newly formed bone was significantly greater in HA-DBBM compound grafting group than in the other two groups. Consistently, Micro-CT assessment revealed significantly more trabecular bone (BV/TV and Tb.N) in HA-DBBM compound group than in the other two groups, respectively (P < 0.05). Moreover, the trabecular bone was significantly more continuous (Tb.Pf) in HA-DBBM compound group than in the other two groups, respectively (P < 0.05).

CONCLUSION

HA not only significantly promoted new bone formation in rats calvarial CSDs but also improved the handling ability of DBBM.

Clinical, radiographic, and aesthetic outcomes at two narrow-diameter implants to replace congenital missing maxillary lateral incisors: A 3-year prospective, clinical study

INTRODUCTION

To present the 3-year clinical, radiographic, and aesthetic outcomes in patients with congenitally missing lateral incisors rehabilitated with two narrow-diameter implants (NDIs).

METHODS

The original population consisted of 100 patients rehabilitated with a cement-retained bi-layered zirconia single-unit crown supported by either a Ø2.9 mm (Test) or a Ø3.3 mm (Control) NDI (n = 50). At the 1- and 3-year follow-up (T2, T3), implant survival rate, crestal bone level (CBL) changes, biological, and technical complications were recorded, while the assessment of the aesthetic outcomes was performed using the Copenhagen Index Score.

RESULTS

Seventy-four patients Ø2.9 mm (n = 39) or Ø3.3 mm (n = 35) reached T3, as 24 patients were lost to follow-up and 1 implant (Ø3.3 mm) was removed. Throughout the observation period, minimal CBL changes (i.e., <1 mm) were detected between groups. Despite the positive aesthetic scores recorded (i.e., 1-2), at T3 20% of patients rehabilitated with a Ø3.3 mm versus 2.6% of patients Ø2.9 mm displayed an alveolar process deficiency (Score 3). No additional technical and/or mechanical complications were recorded between T2 and T3. Tooth vitality was maintained in all neighboring teeth. Peri-implant probing depths and plaque scores remained low in both groups (p > 0.05).

CONCLUSION

The use of 2.9 or 3.3 diameter implants showed comparable favorable mid-term results in terms of survival rate, CBL, and aesthetic outcomes. Hence, clinicians should rely on the use of such NDIs when replacing maxillary lateral incisors.

Clinical analysis of the tooth-implant papilla for two narrow-diameter titanium-zirconium implants in the anterior area: prospective controlled clinical study

BACKGROUND

Rehabilitation of the anterior area when the mesio-distal space is reduced is a challenge for the clinician, due to the patient's anatomical limitations and aesthetic requirements. Narrow Diameter Implants (NDI) are an option of treatment when the standard diameter implant is not possible, but the evidence is scarce. This prospective clinical study aims to analyze the formation of the tooth-implant papilla between the implant and the adjacent natural tooth in the maxillary lateral incisors and mandibular incisors.

METHODS

A total of 40 patients treated with NDI, of titanium-zirconium (Ti-Zr) alloy i.e., 2.9 mm Test Group (TG) and 3.3 mm Control Group (CG), were included. The mesiodistal distance between the adjacent natural teeth was used for implant selection, maintaining 1.5 mm between the fixation and the adjacent tooth. Clinical assessment was performed by a clinical examiner at 6 and 12 months after the final prosthesis. The primary variable was the Jemt Papillary Index. Also, implant survival rate (SR), complications, Implant Stability Quotient (ISQ), and patient-reported outcomes measures (PROMs) such as aesthetics, chewing, phonation, comfort, and self-esteem were analyzed.

RESULTS

A significant amount of papilla filling was observed concerning the baseline, with a trend towards more formation of the papilla in the TG, with a JPI score of 3. No significant differences were observed between the two groups regarding implant SR, clinical parameters, and complications. In terms of PROMs, a higher satisfaction in the TG was observed, with significant intergroup differences for aesthetics, comfort, self-esteem, and primary stability ISQ (TG: 59.05 (SD: 5.4) vs. CG: 51.55 (SD: 5.7)).

CONCLUSIONS

The 2.9 mm diameter Ti-Zr implants achieved a formation of papilla similar to 3.3 mm implants in the anterior region at 12 months of follow-up after the final prosthetic restoration. The use of Ti-Zr implants with a diameter of 2.9 mm to rehabilitate single teeth in areas of the anterior region, where the mesiodistal distance is limited, showed favorable clinical results and a high degree of satisfaction during 1 year of observation similar to 3.3 mm dental implants.

TRIAL REGISTRATION

This study was retrospectively registered in ClinicalTrials.gov with the number NCT05642520, dated 18/11/2022.

Evaluation of the clinical safety and performance of a narrow diameter (2.9 mm) bone-level implant: a 1-year prospective single-arm multicenter study

PURPOSE

Narrow-diameter implants facilitate single-tooth restoration when interdental or inter-implant spaces and bone volume are inadequate for using standard diameter implants. This study reports the short-term data on the clinical safety and performance of a bone-level-tapered two-piece implant with a 2.9 mm diameter in the clinical practice setting. This study was retrospectively registered on March 1st, 2016 (NCT02699866).

METHODS

Implants were placed in partially healed extraction sockets of the central and lateral incisors in the mandible and lateral incisors in the maxilla for single-tooth replacement. The primary outcome was to assess implant survival at 12 months after placement. Secondary outcomes included implant success, pink esthetic score, marginal bone-level changes, and safety.

RESULTS

Twenty four males and 17 females with a mean age of 44.5 (± 18.3 standard deviation) received the implant. Three out of 41 implants were lost yielding a survival rate of 92.7% (95%-CI: 79.0%; 97.6%) at 1 year. One patient reported an ongoing foreign body sensation, pain, and/or dysesthesia at month 12. The average pink esthetic score at 6 months was 11.2 (95%-CI: 10.5; 11.9). The bone level was stable with a mean bone-level change of-0.3 mm (± 0.42 mm standard deviation) at 1 year after implantation. No serious adverse events or adverse device events were reported.

CONCLUSIONS

The use of a 2.9 mm diameter bone-level-tapered implant is a safe and reliable treatment option for narrow tooth gaps at the indicated locations. Overall performance and good survival rates support their use in cases, where wider implants are unsuitable.

Marginal bone level changes around dental implants with one or two adjacent teeth - A clinical and radiographic retrospective study with a follow-up of at least 10 years

AIM

To compare mean bone level (mBL) changes around dental implants with one or two adjacent teeth after a function time of ≥10 years.

MATERIALS AND METHODS

One hundred thirty three periodontally compromised patients (PCPs) with 551 implants enrolled in supportive periodontal care (SPC) were screened. Implants were categorized either into group TIT (tooth-implant-tooth) or into group TIG (tooth-implant-gap). MBL changes from delivery of restoration (i.e., baseline) to follow-up were calculated in millimeters and compared between implants and adjacent teeth. Survival rates and the need for surgical interventions during SPC were recorded.

RESULTS

Eighty seven patients with 142 implants were re-evaluated after a mean observation time of 14.5 ± 3.5 years. The mBL at mesial implant sites in the TIT group increased -0.07 ± 0.92 mm and decreased in the TIG group 0.52 ± 1.34 mm, respectively (95% CI: 0.04/1.14, p = .037). At distal implant sites, the mBL in the TIT group increased -0.08 ± 0.84 mm and decreased 0.03 ± 0.87 in the TIG group, respectively (95% CI: -0.20/0.42, p = .48). The overall implant loss rate was 3.5% (n = 5; 2 TIT, 3 TIG), without a statistically significant difference between the two groups (95% CI: 0.18/7.07, p = .892). Tooth loss rates (TIT: 12.3%, TIG: 12.3%) were not statistically significantly different (OR = 1.00, p = .989).

CONCLUSION

High tooth and implant survival rates were observed in PCPs. The presence of one or two adjacent teeth seemed to have no impact on marginal bone level changes.

Peri-implantitis as the consequence of errors in implant therapy

Peri-implantitis is a plaque-associated pathologic condition occurring in tissues around dental implants, characterized by inflammation in the peri-implant mucosa and subsequent progressive loss of supporting bone. It is a highly prevalent disease, as extensively estimated by large-population, cross-sectional studies. As peri-implant diseases represent opportunistic infections, it is reasonable to assume that nonideal conditions, local and/or general, may favor the progression of peri-implant inflammation. Some of these conditions could be a result of poor planning and/or inadequate execution of any step of the entire process treatment. This article describes the major possible factors in implant therapy that may lead to peri-implantitis. For some of these (ie, inappropriate patient selection, insufficient periodontal therapy, lack of diagnosis and management of peri-implant mucositis, erratic supportive peri-implant/periodontal therapy) there is a good level of evidence, whereas for others (ie, wrong implant placement, poor postoperative care, inadequate prosthetic reconstruction, lack of assessment and management of peri-implant soft-tissue deficiencies) there is little scientific evidence. More research is therefore needed to clearly identify the errors and/or complications possibly leading to peri-implantitis, particularly over the long term.

Same-Day Digital Dentistry Restorative Workflow for Single Immediate Provisionalization of Narrow-Diameter Implants: An Exploratory Prospective Study

This study evaluated the two-year clinical outcomes of 3.1 mm diameter dental implants, immediately provisionalized and later restored using same-day dentistry, in 10 patients receiving 11 narrow-diameter (3.1 mm) single implants. Each implant was placed and immediately restored with a provisional crown after placement. At least 2 months after placement, the implant was restored with a prefabricated titanium abutment and an all-ceramic crown using a same-day dentistry protocol. Clinical outcomes, including apical bone loss, probing depths, gingival index, and surgical and prosthetic complications, were documented. There was no implant failure over the course of two years. No surgical complications were reported. Two cases lost provisional crowns. One crown needed to be remade due to esthetic concern. The cumulative two-year survival rate of the implants was 100%. Implant bone loss after two years of functional loading was −0.56 ± 0.54 mm and −0.32 ± 0.68 mm for mesial and distal crestal bone, respectively. Two prosthetic complications included recementation of a crown and remaking of a crown. This exploratory study suggests that immediate provisionalization and a same-day restorative dentistry digital workflow protocol for narrow-diameter implants appear to be predictable clinical procedures with no reported surgical complications and minimal prosthetic complications.

The peri-implant mucosa color: A systematic appraisal of methods for its assessment and clinical significance

BACKGROUND

Peri-implant mucosa color (PMC) seems to be one of the main parameters affecting the esthetic outcome of implant therapy. However, more emphasis should be given to its assessment and reporting.

PURPOSE

To describe the available evidence on methods to assess and report the color of the peri-implant mucosa (PMC) and the respective clinical relevance.

MATERIAL AND METHODS

A comprehensive electronic and manual search was performed to identify clinical studies reporting on PMC.

RESULTS

A total of 121 studies were included. PMC was evaluated at the time of the follow-up visit (chairside) in 45.5% studies. PMC assessment was performed qualitatively, by comparing PMC with adjacent and/or contralateral gingiva (78.6%) or quantitatively, using spectrophotometry (20.7%) or a software on clinical photographs (0.8%). The most performed method to assess PMC was through esthetic indices (76.9%), either at the time of the follow-up visit (chairside) or at later time point using photographs. Quantitative reporting of PMC included averages of points from esthetic indices or color differences to natural gingiva expressed with the CIELAB color system. PMC assessment allowed describing color discrepancies compared to natural gingiva, evaluating color changes over time, and comparing the outcomes of different treatment modalities. PMC assessment through spectrophotometry was additionally utilized to assess the role of mucosal thickness (MT) on PMC.

CONCLUSIONS

Various methods for PMC assessment and reporting were described, including visual assessment, mainly through esthetic indices, and spectrophotometry. PMC evaluation has allowed to demonstrate the factors affecting the color of the peri-implant soft tissue, such as the type of abutment/restoration, MT, and soft tissue augmentation.

The Comparison of Survival Rates between Narrow Diameter Implants and Standard Diameter Implants: An Updated Meta-analysis

Background

One of the key objectives is to update knowledge in order to develop treatment and care recommendations based on research findings. The purpose of the present meta-analysis was to compare the survival rate of narrow dental implants (NDI) with standard dental implants (SDI).

Methods

The international databases targeted for conducting a broad search included PubMed (Medline), Scopus, Web of Sciences, and Embase (Elsevier), which were searched to retrieve articles from January 1, 2000, to the end of July 2022. After the search, studies were screened based on the title, abstract, and full text, and finally, information extraction and quality assessment of the articles were performed based on the Newcastle-Ottawa Quality Assessment Scale checklist. All analyzes were conducted in STATA software Version 17.

Results

After the screening, 8 retrospective and prospective cohort studies remained in the research for analysis. The outcomes demonstrated that the probability of healthy teeth in the 2 groups of NDI and SDI was not substantially different at least a year after implantation, and the risk ratio of tooth loss in the NDI group was comparable to that of the SDI group (RR, 1.00; 95% CI, 0.98, 1.02; I2: 28.37 %; P = 0.252). In addition, the survival rates in the 2 groups were also measured using meta-analysis and the results showed the survival rates in the 2 groups of NDI and SDI were almost equal. In the SDI group, the survival rate was equal to 94% (95% CI, 90%-98%), and in the NDI group, it was equal to 94% (95% CI, 92%- 98%).

Conclusion

Based on the results of the present meta-analysis, the survival rates in the both NDI and SDI groups were almost equal.