The role of dental implant abutment design on the aesthetic outcome: preliminary 3-month post-loading results from a multicentre split-mouth randomised controlled trial comparing two different abutment designs.

PURPOSE: To evaluate whether there are aesthetic and clinical benefits to using a newly designed abutment (Curvomax), over a conventional control abutment (GingiHue). MATERIALS AND METHODS: A total of 49 patients, who required at least two implants, had two sites randomised according to a split-mouth design to receive one abutment of each type at seven different centres. The time of loading (immediate, early or delayed) and of prosthesis (provisional crowns of fixed prosthesis) was decided by the clinicians, but they had to restore both implants in a similar way. Provisional prostheses were replaced by definitive ones 3 months after initial loading, when the follow-up for the initial part of this study was completed. Outcome measures were: prosthesis failures, implant failures, complications, pink esthetic score (PES), peri-implant marginal bone level changes, and patient preference. RESULTS: In total, 49 Curvomax and 49 GingiHue abutments were delivered. Two patients dropped out. No implant failure, prosthesis failure or complication was reported. There were no differences at 3 months post-loading for PES (difference = -0.15, 95% CI -0.55 to 0.25; P (paired t test) = 0.443) and marginal bone level changes (difference = -0.02 mm, 95% CI -0.20 to 0.16; P (paired t test) = 0.817). The majority of the patients (30) had no preference regarding the two abutment designs; 11 patients preferred the Curvomax, while five patients preferred the GingiHue abutments (P (McNemar test) = 0.210). CONCLUSIONS: The preliminary results of the comparison between two different abutment designs did not disclose any statistically significant differences between the evaluated abutments. However the large number of missing radiographs and clinical pictures casts doubt on the reliability of the results. Longer follow-ups of wider patient populations are needed to better understand whether there is an effective advantage with one of the two abutment designs.

Implant placement in the esthetic area: criteria for positioning single and multiple implants.

Patient expectations from implant treatment have changed over the years and esthetics plays an important role in defining what is now called success of rehabilitation. Of the many factors that influence the outcome of the rehabilitation, the two main ones are the bone and soft-tissue deficiencies at the intended implant site. Many surgical approaches are described in terms of timing of implant placement and management of regenerative procedures. The aim of this article is to discuss the different implant placement alternatives in the esthetic area, in particular: (i) the timing of implant placement/regenerative procedures/skeletal growth/altered passive eruption; (ii) the correct three-dimensional position of the fixture between the cuspids and in the premolar area; (iii) multiple missing teeth in the esthetic area with single tooth/pontic or cantilevered options/prosthetic compensation; (iv) placement of implants into infected sites; and (v) the influence of abutment and crown morphology on implant position. Combining our long-standing clinical experience and the pertinent literature, the following conclusions can be drawn: Immediate implant placement can be a successful procedure in terms of esthetics but it is technique sensitive and requires an experienced team. Immediate placement is less traumatic to the patient as fewer surgical procedures are involved and patients tend to prefer this clinical approach with regards to quality of life. The diagnostic phase is of utmost importance, with not only bone and soft tissue deficiencies being addressed but also: skeletal growth, dental/implant soft tissue parameters such as altered passive eruption and the morphology of the roots adjacent to the edentulous area. Post-extraction immediate loading is feasible in infected sites. The correct position of the fixture should follow widely accepted guidelines but the abutment morphologies play a role in the vestibular/palatal position of the implant. The long axis of the implant, aiming at the incisal edge of the future restorations, is the most appropriate implant position when a shoulder-less abutment is used and allows a restorative crown morphology with a cervical contour resembling a natural tooth. The use of a shoulder-less abutment gives more space for the tissue to grow compared with the traditional abutment with shoulder finish line.

A Retrospective Periodontal Assessment of 137 Teeth After Featheredge Preparation and Gingittage.

The aim of this study was to retrospectively evaluate the periodontal response of periodontally healthy teeth prosthetically restored using a featheredge finish line preparation combined with a light rotary curettage (gingittage). A total of 137 restored teeth were included in the study. Mean follow-up time was 18.2 months (range: 6 to 60 months). Bleeding on probing was noted in 18% of cases, while the Plaque Index was found to be 11%. The probing depth in 99.4% of cases was ≤ 3 mm. In only 7 cases (5.1%), a slight restoration margin exposure was recorded. Although randomized controlled studies with longer follow-up are advocated, the present investigation seems to suggest that this protocol is a viable procedure.

Immediate Versus Delayed Loading of Postextraction Implants: A Long-Term Retrospective Cohort Study.

PURPOSE: To compare the long-term clinical and radiographic outcomes between immediate loading (IL) and conventional loading of implants placed immediately in fresh extraction sockets. MATERIALS AND METHODS: Demographic data, implant details, and periapical radiographs of patients were collected. The long-term marginal bone level remodeling and implant survival rate were calculated. RESULTS: Twenty-one patients (mean age 52.55 ± 14.61 years) with 35 implants immediately inserted into postextraction sites (22 immediate loaded and 13 delayed loaded) were analyzed. The mean follow-up duration was 6 years (range 2-11 years). The implant cumulative survival rate was 96.5%. At the longest follow-up, the mean crestal bone level averaged 0.144 ± 0.705 for IL and 0.161 ± 0.877 for delayed loading, respectively. The mean implant aesthetic score was 7. CONCLUSIONS: IL does not negatively influence the long-term prognosis of implants inserted into fresh extraction sockets.

Buccolingual implant position and vertical abutment finish line geometry: two strictly related factors that may influence the implant esthetic outcome.

PURPOSE: Three-dimensional implant positioning has always been a highly debated topic especially in the esthetic zone due to many problems related to buccal bone resorption. A new concept in implant position, dictated by changing the abutment finish line, is presented in the following article. MATERIALS AND METHODS: The actual guidelines on implant position agree that in the bucco-palatal dimension, the implant should be placed more toward the palatal preserving at least 2 mm of buccal bone. However, changing the abutment finish line geometry from horizontal to vertical, the authors' geometry of choice, the surgical approach in the bucco-palatal direction has been modified accordingly to ensure final restorations that will guarantee long-term soft tissue stability. RESULTS: The emergence angle of the natural teeth has been the authors' guide to establish the implant position which should be located with the long axis of the implant corresponding to the incisal edge of the future restoration. Observation of the clinical results in the past years strongly supports this approach. CONCLUSIONS: The surgical and prosthetic concepts described in this article allow the clinician to recreate a pleasant and natural-looking esthetics while the patient can easily maintain a proper hygiene around the implant. However, despite the promising clinical results obtained by the authors, further clinical and randomized researches should be realized to validate the above-proposed approach.