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

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.

Purpose: To evaluate the accuracy of full-arch digital implant impressions taken using intraoral scanners and analyse the related variables.

Materials and methods: An electronic search of studies on the accuracy of digital implant impressions in fully edentulous arches from 1 January 2012 to 29 February 2020 was conducted in PubMed, EMBASE and the Cochrane Library. Only peer-reviewed experimental or clinical studies written in English were included. Studies assessing the accuracy of restorations, case reports, clinical reports, technical reports and reviews were excluded. The literature screening, article reading and assessment of risk of bias were carried out by two reviewers. The data on the study characteristics, accuracy outcomes and investigated variables were extracted.

Results: After removal of duplicates, a total of 166 studies were identified, of which 42 were initially selected for full-text reading and 30 were included in the final analysis (29 in vitro studies and one in vivo study). The trueness of digital implant impressions ranged from 7.6 to 731.7 μm, and the precision ranged from 15.2 to 204.2 μm. Angular deviations were between 0.13 and 10.01 degrees. Considering 100 μm and 0.4 degrees as clinically acceptable levels of deviation, 18 studies reported linear/distance/3D deviations larger than 100 μm and only two studies reported angular deviations below 0.4 degrees. The effect of interimplant distance/length of the arch scanned/scanning sequence/scanning range/implant position (nine studies), implant angulation (ten studies), implant depth (five studies), implant connection (two studies), operator experience (six studies), scan body type (three studies), intraoral scanner type (six studies), scanning strategy (two studies) and modification technique (three studies) was investigated.

Conclusions: Based on the results of the included studies, full-arch digital implant impressions taken using intraoral scanners are not sufficiently accurate for clinical application. Accuracy varies greatly with interimplant distance, scan body type, intraoral scanner type and operator experience, whereas implant angulation, implant connections and implant depth have no effect. The effects of scanning strategy and modification technique need further investigation.

Purpose: To evaluate short-term clinical and radiographic outcomes of bone regeneration procedures using thin cortical porcine xenogeneic bone plates in combination with autogenous bone chips compared with thin autogenous cortical plates and autogenous bone chips.

Materials and methods: A total of 19 patients (12 women and 7 men, mean age 58.24 ± 3.09 years) were randomly allocated to two different groups regarding surgical procedure: autogenous cortical plates (ACP group) and xenogeneic cortical plates (XCP group). Preoperative CBCT scans were performed for each patient. Surgical time and postoperative pain were recorded, as well as tissue healing and graft resorption after 4 months, then another surgical procedure was performed to place dental implants. Data were analysed using an analysis of covariance.

Results: Twenty-one surgical procedures were performed on 19 patients (10 from the XCP group and 9 from the ACP group). The operative time was significantly lower in the XCP group (25.45 ± 3.88 minutes) than in the ACP group (44.10 ± 3.60 minutes). The XCP group also showed less pain, but not significantly less, than the ACP group. The graft resorption rate in the ACP and XCP groups was 2.03 ± 1.58% and 3.49 ± 2.38% respectively, showing no statistically significant difference.

Conclusions: Despite the limited sample size and non-uniform distribution between the maxilla and mandible as surgical sites, the results suggest that XCP and ACP grafts are similar in terms of bone volume gain and graft resorption rate, with no significant differences in wound healing or complication rate. Nevertheless, the XCP group recorded lower pain levels and required significantly less operative time compared to the ACP group.

Purpose: In recent years, dental malpractice claims have increased dramatically worldwide. The present study aimed to categorise and analyse claims related to implant dentistry that resulted in legal decisions in Israel, seeking to contribute to dental risk management and improve patient safety.

Materials and methods: This study analysed legal claims registered by Medical Consultants International between 2005 and 2015. Only closed cases in which a decision was made were included. The parameters studied included patient age and sex, date of the complaint, treatment setting (private/public clinic), description of the adverse event and type of negligence claimed.

Results: The cohort included 709 settled claims out of a total of 1066 that were litigated against dental practitioners in Israel during the study period. Of the patients included, 60.0% were women and 63.9% were aged 40 to 59 years. The most common treatment-related damage was neural injury in 133 patients (18.7% of the cohort). Unplanned changes in the treatment plan and violation of autonomy were the most frequent documentation-/information-related claims (66.3% and 32.7%, respectively). The legal responsibility of the dental practitioner was acknowledged in 89.0% of cases. Dental practitioners working in the private sector were more likely to be sued due to violation of autonomy than those working in public clinics.

Conclusions: Although the main cause for lawsuits was actual bodily injury, the high percentage of documentation-/information-related malpractice claims calls for increased awareness of patients' autonomy and rights. Practitioners should dedicate a significant part of the entire treatment time to preoperative diagnosis and planning.