Less marginal bone loss around bone-level implants restored with long abutments: A systematic review and meta-analysis

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

OBJECTIVE

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

MATERIAL AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Analysis of ultra-short implants with different angulations: a retrospective case-control study with 2 to 9 years of follow-up

OBJECTIVES

Does the angulation of ultrashort implants influence the stability of the peri-implant bone? The present study aimed to evaluate the effectiveness of non-axial ultrashort implants after 2 to 9 years of follow-up in resorbed alveolar ridges.

MATERIALS AND METHODS

All partially edentulous patients with ultrashort implants (< 6 mm) used in the posterior region of an atrophic mandible or maxilla, to support partial dentures in conjunction with standard implants, were included in this study. Peri-implant bone loss, success and survival rates, crestal bone levels, crown-to-implant ratio and implant angulation were measured for each implant. Implants were divided into two groups: straight implants with angulation < 17° (control group) and tilted implants with angulation > 17° (test group). Statistical analysis was used to find any significant differences between the two study groups and to investigate significant linear correlations among all the variables (p = 0.05).

RESULTS

A total of 42 ultrashort implants with a mean of 4 years of follow-up were included: 20 ultrashort axially loaded implants and 22 tilted implants. Mean crestal bone levels from baseline loading to maximum follow-up did not reveal statistical differences in regard to PBL; mean success and survival rates were 100% in all groups.

CONCLUSIONS

PBL, success and survival rates of axial ultrashort implants and tilted ultrashort implants are comparable to those of conventional implants.

CLINICAL RELEVANCE

This retrospective study revealed that ultrashort implants, even when placed with an angulation > 17°, can safely be used to support partial fixed prostheses. Further prospective clinical studies with larger samples and prospective design are needed to confirm these findings.

Influence of crestal and sub-crestal implant position on development of peri-implant diseases: a 5-year retrospective analysis

OBJECTIVES

The aim of the present study was to evaluate the influence of crestal and subcrestal implant position on development of peri-implant diseases.

MATERIALS AND METHODS

The study was designed as a retrospective clinical and radiographic analysis. Implant-supported fixed dental prostheses were allocated in two groups: with the shoulder (i) placed in sub-crestal level and (ii) placed at bone level. For each patient, the following clinical variables were assessed: FMPS, FMBS, PlI, BOP, and PD. After prothesis delivery, an intraoral radiograph was obtained; this exam was performed also at 5 years of observation period.

RESULTS

No statistically significant difference was found in terms of FMPS and FMBS at baseline and after 5 years follow-up (P < 0.05). A statistically significant difference was assessed between PD of control group and test group (P = 0.042). Patient-based analysis showed a 25.6% of peri-implant mucositis and 32.6% of peri-implantitis for implants placed with the shoulder in crestal position, while for implants inserted in sub-crestal position the percentage of peri-implant-mucositis and peri-implantitis were 19%; no statistically significant difference was found between groups after 5 years (P < 0.05).

CONCLUSIONS

Within the limitation of the present study, the clinical and radiographic outcomes showed that the percentage of peri-implant mucositis and peri-implantitis was not statistically significant for both groups after 5 years follow-up.

CLINICAL RELEVANCE

The outcomes of present study clinically demonstrated that a deep position of implant shoulder did not provide any benefits. On the contrary, it may be considered a possible risk indicator for implant diseases.

Conometric Connection for Implant-Supported Crowns: A Prospective Clinical Cohort Study

BACKGROUND

Traditional screw or cemented connections in dental implants present limitations, prompting the exploration of alternative methods. This study assesses the clinical outcomes of single crowns and fixed partial prostheses supported by conometric connections after one year of follow-up.

METHODS

Twenty-two patients received 70 implants, supporting 33 rehabilitations. Biological responses and prosthodontic complications were evaluated at baseline, 6 months, and 12 months.

RESULTS

All implants exhibited successful osseointegration, with no losses or peri-implant inflammation. Marginal bone levels showed minimal changes, well below pathological thresholds. The difference in marginal bone loss (MBL) was -0.27 ± 0.79 mm between T0 and T1, and -0.51 ± 0.93 mm between T0 and T2. No abutment screw loosening or crown chipping occurred. However, coupling stability loss was observed in nine cases.

CONCLUSIONS

The conometric connection demonstrated successful integration and minimal complications after one year. This alternative shows promise, particularly in simplifying handling and improving marginal adaptation. Further research with larger sample sizes and longer follow-up is warranted for comprehensive validation.