International journal of oral implantology (Berlin, Germany)最新文献

Purpose: To investigate the effect of platelet-rich fibrin on bone formation by investigating its use in guided bone regeneration, sinus elevation and implant therapy.

Materials and methods: This systematic review and meta-analysis were conducted and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The eligibility criteria comprised human controlled clinical trials comparing the clinical outcomes of platelet-rich fibrin with those of other treatment modalities. The outcomes measured included percentage of new bone formation, percentage of residual bone graft, implant survival rate, change in bone dimension (horizontal and vertical), and implant stability quotient values.

Results: From 320 articles identified, 18 studies were included. Owing to the heterogeneity of the investigated parameters, a meta-analysis was only possible for sinus elevation. There is a general lack of data from comparative randomised clinical trials evaluating platelet-rich fibrin for guided bone regeneration procedures (only two studies), with no quantifiable advantages in terms of new bone formation or dimensional bone gain found in the platelet-rich fibrin group. For sinus elevation, the meta-analysis demonstrated no advantage in terms of histological new bone formation in the control group (bone graft alone) compared with the test group (bone graft and platelet-rich fibrin). Two studies demonstrated that platelet-rich fibrin may shorten healing periods prior to implant placement. Platelet-rich fibrin was also shown to slightly enhance primary implant stability (implant stability quotient value < 5) as assessed using implant stability quotients and resonance frequency analysis parameters, with no histological data evaluating bone-implant contact yet available on this topic. In one study, platelet-rich fibrin was shown to improve the clinical parameters when utilised as an adjunct for the treatment of peri-implantitis.

Conclusions: In the majority of studies, platelet-rich fibrin offered little or no clear advantage in terms of new bone formation as evaluated in various studies on guided bone regeneration and sinus elevation, nor in implant stability and treatment of peri-implantitis. Various authors and systematic reviews on the topic have now expressed criticism of the various study designs and protocols, and the lack of appropriate controls and available information regarding patient selection. Well-controlled human studies on these specific topics are required.

Purpose: To investigate whether implant position (adjacent to teeth/implants vs most distal position in the arch) influences the clinical outcomes of short (≤ 6 mm) non-splinted implants.

Materials and methods: A systematic electronic search of human randomised clinical trials and prospective cohort studies was performed using the PubMed, Embase and Cochrane Central Register of Controlled Trials (Central) databases. A manual search of implant-related journals was also performed. A meta-analysis was conducted to compare survival rate, marginal bone loss and prosthetic complications based on implant position.

Results: Overall, 11 studies were included to give a total of 388 non-splinted short implants (269 adjacent, 119 distal) followed up over a period ranging from 12 to 120 months. No significant differences in survival were found when comparing adjacent and distal positioning for both arches, and no significant differences were found for marginal bone loss or prosthetic complications between groups regardless of position.

Conclusions: Short implants supporting single crowns presented similar outcomes when placed in the most distal position in the arch or between adjacent teeth or other implants.

Purpose: To investigate the use of platelet-rich fibrin for alveolar ridge preservation compared to natural healing, bone graft material and platelet-rich fibrin in combination with bone graft material.

Materials and methods: The present systematic review was conducted and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. The review examined randomised controlled trials comparing the clinical outcomes of platelet-rich fibrin with those of other modalities for alveolar ridge preservation. Studies of third molar extraction site healing were excluded. The studies were classified into three categories: natural wound healing vs platelet-rich fibrin; bone graft material vs platelet-rich fibrin; and bone graft material vs bone graft material and platelet-rich fibrin.

Results: From 179 articles identified, 16 randomised controlled trials were included. Owing to the heterogeneity of the investigated parameters, it was not possible to perform a meta-analysis. In total, 10 randomised controlled trials compared platelet-rich fibrin to natural wound healing, with seven of these demonstrating favourable outcomes to either limit postextraction dimensional changes or improve new bone formation in the platelet-rich fibrin group. Three of four studies comparing healing with bone graft material to platelet-rich fibrin found that the latter led to significantly greater horizontal or vertical bone resorption, and the bone graft material was more able to maintain the ridge dimensions. Two out of three randomised controlled trials investigating healing with both bone graft material and platelet-rich fibrin reported better outcomes using this combined approach than with bone graft material alone. All studies investigating soft tissue healing with platelet-rich fibrin demonstrated better outcomes in the platelet-rich fibrin group.

Conclusions: The majority of studies comparing healing with platelet-rich fibrin to natural healing concluded that the former more successfully limits postextraction dimensional changes than the latter. However, 75% of studies investigating platelet-rich fibrin vs bone graft material reported better results in the bone graft group with respect to its ability to maintain postextraction dimensional changes. The addition of platelet-rich fibrin to bone graft material may improve clinical outcomes, although data are limited.

Purpose: To assess the fit and cement gap of fixed partial dentures supported by two implants made using conventional and digital workflows.

Materials and methods: Patients requiring fixed partial dentures supported by two implants were included in the study. Forty-eight zirconia fixed partial denture bars supported by two implants (AnyOne, MegaGen, Daegu, South Korea) were produced using a conventional (n = 24, group C) and digital (n = 24, group D) workflow. All implants had the same internal connection prosthetic platform. Silicone open tray impressions with splinted copings (group C) and digital impressions using a Trios 3 intraoral scanner (3Shape, Copenhagen, Denmark) (group D) were taken for each patient. The fit and cement gap were assessed by scanning electron microscopy on the verified master cast. The distance between reference points on the titanium base and implant analogue was measured with and without tightening the prosthetic screw. The difference in distance was calculated and represented the misfit (Dmisfit). The cement gap (Dcement) was measured as the shortest vertical distance from the inferior edge of the bar to the top edge of the titanium base.

Results: The median Dmisfit values (interquartile range) differed significantly (P < 0.05) between the groups, with 59 (60) µm for group C and 78 (88) µm for group D. Fixed partial dentures fabricated using a digital workflow presented lower Dcement values (35 [26] µm) than the conventional group (38.9 [23] µm) (P < 0.05).

Conclusions: Both workflows produced different levels of fit and differently sized cement gaps when measured on the master casts using scanning electron microscopy. A cast-free digital workflow was associated with a smaller cement gap, but larger misfit was detected when measuring on the verified master cast.

Achieving predictable success with implants in the aesthetic zone is essential for clinicians. Promoting marginal bone and stability of the gingival environment is key to obtaining a predictable aesthetic outcome. The present study aimed to describe a technique that combines a flapless approach to immediate extraction and placement of sloped implants, using an acellular dermal matrix to contain the coronal aspect of a deproteinised bovine bone mineral graft. This minimally invasive technique results in stable augmentation of soft tissue thickness to ensure predictable aesthetic results. A collection of case reports with a follow-up period of up to 45 months is presented to demonstrate the surgical technique. Clinical presentation showed relative stability of the soft tissue margins during the evaluation period.

Purpose: To evaluate the crestal bone loss and implant stability quotient trends of photofunctionalised versus untreated implants.

Materials and methods: A total of 34 patients (age 46.94 ± 12.03 years) with bilateral single missing teeth in the same arch were enrolled in this study. Each patient received an untreated implant on one side (control group, n = 34) and a photofunctionalised implant on the contralateral side (test group, n = 34). Crestal bone loss was assessed at the time of crown insertion and 1 year later. The osseointegration speed index was evaluated for both the control and test group. An independent t test was used for intergroup comparisons of crestal bone loss and osseointegration speed index. Bivariate analysis was performed for the confounding variables.

Results: The test group showed a statistically significantly higher osseointegration speed index (3.07) as compared to the control group (1.29) (P < 0.01). Statistically significantly higher crestal bone loss was observed in the control group (-0.57 ± 0.41 mm) as compared to the test group (-0.27 ± 0.35 mm) (P < 0.01). The difference between mean Plaque Index and Bleeding Index in the control (0.74/0.38) and test group (0.73/0.35) was statistically insignificant (P > 0.05). A negative correlation (r = -0.272) was noted between implant diameter and crestal bone loss. A positive correlation (r = 0.402) was observed between implant length and osseointegration speed index.

Conclusion: Implants with photofunctionalised surfaces reduce overall healing time and crestal bone loss. Photofunctionalisation is an effective aid for chairside conditioning of implant surfaces to achieve faster osseointegration with good crestal bone stability.

Purpose: To investigate the effect of laser microtextured collars or laser microtextured abutments on clinical measures that may relate to improved implant success and survival.

Materials and methods: This review was registered on the PROSPERO database and conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. MEDLINE (via PubMed) and Embase were screened for studies with at least 10 participants and followed up for at least 1 year, reporting on the following clinical outcomes: radiographic marginal bone level, peri-implant probing depth, soft tissue index and failure rates of implants with laser microtextured collars or laser microtextured abutments. The quality of the studies was assessed using the Cochrane risk-of-bias tool or the Newcastle-Ottawa scale.

Results: After removal of duplicates, 86 articles were identified. A total of 25 articles were included after screening. Four were randomised controlled trials, two were non-randomised controlled trials, two were prospective studies, five were retrospective cohort studies and twelve had no control group. Most comparative studies reported that laser microtextured collar implants had less marginal bone loss and shallower peri-implant probing depth than machined collar implants. Only two studies had controls other than machined collar implants; in these, the use of laser microtextured collar implants was not observed to be significantly different. Three studies reported reduced marginal recession in laser microtextured collar implants when compared to machined collar controls. No difference in failure rate was observed between laser microtextured collar and machined collar implants. One study reported on peri-implant diseases and favoured laser microtextured collar implants. Three papers reported using laser microtextured abutments with no control, but no specific conclusions could be drawn.

Conclusions: Laser microtextured collar implants appear to reduce marginal bone loss and peri-implant probing depth when compared to machined collar implants. There is weak evidence to suggest that laser microtextured collar implants may also improve aesthetic outcomes and reduce incidence of disease. Research is required regarding laser microtextured abutments, and studies comparing laser microtexturing with alternative solutions are also lacking.