Journal of Oral Implantology最新文献

A particulate cancellous bone and marrow (PCBM) graft combined with titanium (Ti-) mesh tray has become one of the most popular mandibular reconstruction methods. The technique has been applied to the mandibular discontinuity defects after segmental mandibulectomy. To the best of our knowledge, there are no reports on using the technique after hemimandibulectomy, during which a wide mandibular resection, including the condyle, is performed. Here, we first report a case of mandibular reconstruction after hemimandibulectomy, using a plate and soft-tissue free flap, followed by a Ti-mesh and PCBM harvested from the bilateral posterior ilia, which was successful. This case report first revealed how bone resorption occurred clinically in mandibular reconstruction using PCBM and Ti-mesh tray after hemimandibulectomy. We also revealed the high predictability of the mandibular reconstruction using PCBM and Ti-mesh tray after hemimandibulectomy. Our report also provides a guiding principle to overcome the limitation of mandibular reconstruction using PCBM and Ti-mesh tray after hemimandibulectomy. However, our manuscript has limited evidence, being a case report.

Selective serotonin reuptake inhibitors (SSRI) are commonly prescribed to treat mental health disorders, and previously published literature, although scarce, has shown a significant association between SSRI use and dental implant failure. This systematic review and meta-analysis aimed to examine whether such an association exists and, if so, to determine its strength. Reviewers performed an extensive search of the literature, last accessed in June 2022 in PubMed/Medline, Embase, and Cochrane databases using MeSH terms. Retrospective and prospective observational cohort and experimental studies evaluating the role of SSRI on dental implant failure among individuals ≥18 years of age, with a minimum follow-up of 6 months after implant placement, were deemed eligible. The search yielded a total of 6 eligible studies, all retrospective cohorts. Statistical analyses were performed using the statistical software R 4.1.3. Results showed higher implant failure rates among SSRI users vs non-SSRI users at both the patient level (5.6%-19.6% vs 1.9%-8.0%) and the implant level (5.6%-12.5% vs 1.9%-5.8%). The pooled relative risk (RR) of implant failure was more than double among SSRI users at the patient level (pooled RR: 2.44, 95% confidence interval [CI]: 1.68-3.55, P < .01) and at the implant level (pooled RR: 2.34, 95% CI: 1.74-3.15, P < .01) compared with non-SSRI users. DerSimonian and Laird estimates showed homogeneity of the studies (I2 = 0%, P > .05), and funnel plots and Egger's test determined no publication bias across all selected studies at both patient and implant levels. In conclusion, SSRI use is significantly associated with higher implant failure. Providers should be aware of this association and educate patients on the risk of implant therapy when obtaining informed consent.

This in vitro study evaluated the mechanical behavior of different conical connection implant systems after abutment screw withdrawal. Four conical connection systems were selected based on different conical half-angles: Ankylos (5.7°), Cowell (7.0°), Straumann (7.5°), and Astra (11.0°). In each system, 5 implants and abutments were used (n = 5). According to the recommended value, each abutment screw was torqued to settle the abutment and then withdrawn through a predesigned hole of the cemented crown. The retentiveness of the abutment was evaluated by the following mechanical testing. All specimens were subjected to cyclic loading of 20-200 N, 30°, and 4-mm off-axis to the implant axis, for 106 cycles. The pullout forces and axial displacements of the abutments were measured. The data of the Cowell system was obtained from our previous work. All groups other than Astra group, in which abutment loosened after abutment screw withdrawal, passed the cyclic loading test. Straumann group demonstrated a significantly lower pullout force (27.4 ± 21.1 N) than Ankylos (160.1 ± 41.4 N) and Cowell (183.7 ± 30.5 N) groups. All groups showed abutment rebound after screw withdrawal except Straumann group. In addition, Ankylos, Cowell, and Straumann groups demonstrated axial displacement after cyclic loading. In terms of the retentiveness of the abutment after abutment screw withdrawal examined in this study, Ankylos and Cowell groups had much higher retentiveness than Straumann group, while Astra group had none. Conical angle could be a key design parameter to make abutment screw withdrawal after conical abutment settlement feasible, but more studies must be conducted for clinical application.

Oral reconstruction in fully edentulous patients can be challenging at times. Hence, it is important to offer the most suitable treatment option after a detailed clinical examination and treatment plan. This 14-year long-term follow-up report is the clinical case of a 71-year-old nonsmoker who visited the clinic in 2006 and opted for full-mouth reconstruction using Auro Galvano crown (AGC) attachments. Maintenance was performed twice a year for the past 14 years, and the clinical results were satisfactory, with no signs of inflammation or lack of retention of the superstructures. This was associated with a high level of patient satisfaction, as indicated by the Oral Health Impact Profile. Compared to the screw-retained implants over dentures, AGC attachments can be a viable and effective treatment option when restoring fully edentulous arches.

Primary implant stability (PIS) is known to vary with recipient bone mass and density, dental implant design and surgical technique. The objective of this preliminary study was to compare rotational and lateral PIS of same-coronal-diameter conical and parallel implants, using insertion torque recorded with a dental implant motor set and implant stability quotient obtained from resonance frequency analysis (performed with both Osstell and Penguin systems) as measures of rotational and lateral stability, respectively. Additionally, the relationship between PIS and alveolar ridge width (ARW) was explored in both implant types. Sixty dental implants (30 tapered and 30 parallel) were randomly placed with a split-mouth design in 17 patients. Bone density and ARW were estimated from cone beam computed tomography images taken with radiological-surgical templates. Density and width values were similar in the 2 groups (P > .05). Implant coronal diameters were 3.75 mm in all cases, while consistent with the manufacturer's recommendations, final drill bit diameters used were 3.25 and 3.4 mm for parallel and tapered implants, respectively. Insertion torque was higher (P < .05) with parallel implants, but between-group differences in implant stability quotient were not significant (P > .05). In tapered implants, insertion torque was inversely correlated with ARW (P < .001). Notably, significant differences were observed between resonance frequency analysis values from Osstell and Penguin systems (P < .001). In conclusion, future studies should explore how PIS may be influenced by final drill bit size regardless of implant design and potential limits on the effectiveness of tapered implants to achieve good stability in thick low-density bone.

Restoration of edentulous sites with dental implants is increasingly becoming a popular choice. Cross-sectional 3-dimensional imaging using cone-beam computed tomography (CBCT) provides a better depiction of the implant site to help the clinician plan the procedure better. In spite of the advantages, radiation dose will always remain a concern. The evolution of lower-dose protocols is ongoing, but whether those acquisition protocols yield comparable diagnostic information is still not well established. The objective of this study was to evaluate the diagnostic efficacy of a low-dose, 180° rotational CBCT acquisition protocol for evaluating a potential implant site in comparison with a conventional 360° rotational acquisition. Ten dentate and partially edentulous dry human skulls providing 82 randomized implant sites-40 in the maxilla and 42 in the mandible-were chosen for this study. Each skull was imaged using a 360° and a 180° rotational acquisition on a J. Morita Accuitomo CBCT scanner. Evaluation of cortical and trabecular bone, height, width, and proximity to critical structures, such as the inferior alveolar nerve canal and the maxillary sinus, were measured. An oral surgeon and an oral radiologist rated the diagnostic efficacy of the scans by evaluating the above characteristics. Statistical evaluation of the data with linear regression showed significant agreement between both protocol measurements. Kappa analyses yielded a good interobserver agreement. In this proof-of-concept study, CBCT imaging using the lower-dose, modified arc, and 180° acquisition protocol shows comparable results to the conventional 360° protocol for preoperative implant assessment.

The purpose of this study was to evaluate the current evidence on marginal bone-level changes (ΔMBL) around internal connection implants with fixed prostheses by jaw location over time. An electronic literature search for ΔMBL (change in marginal bone level) was conducted in 6 databases. The data from the included manuscripts were categorized by jaw sextant of the implants and duration of follow-up (<2 years, 2-5 years, and >5 years). Meta-analyses were performed on groups with at least 5 studies. A total of 1270 records were screened. Full-text review of 413 papers resulted in a total of 46 studies (representing 2259 patients with 4970 implants) included for quantitative synthesis and analysis. The ΔMBL was summarized at 2 time intervals with the following results: <2 years (anterior maxilla = 0.393 mm [95% confidence interval {CI}, 0.172, 0.613], posterior maxilla = 0.468 mm [95% CI, 0.288, 0.648], and posterior mandible 0.559 mm [95% CI, 0.397, 0.72]), 2 to 5 years (anterior maxilla = 0.683 mm [95% CI, 0.224, 1.142], posterior maxilla = 0.645 mm [95% CI, 0.42, 0.87], and posterior mandible 0.563 mm [95% CI, 0.278, 0.849]). There were insufficient studies in the anterior mandible and with follow-up data over 5 years for quantitative synthesis. Within the limitations of this study, location within the maxillary and mandibular jaws does not seem to influence ΔMBL around internal connection bone level implants with fixed restorations. Although there may be a tendency for greater initial remodeling in the posterior mandible followed by long-term stability, additional studies are needed to evaluate this further.

Guillain-Barré syndrome (GBS) is a rare rapid onset autoimmune peripheral polyneuropathy, most commonly characterized by inflammatory demyelination of peripheral nerves. Patients with GBS are considered higher risk for anesthetic-induced neurotoxicity caused by demyelination. In the present report, a case is described of a 56-year-old man with GBS who experienced mental and lingual nerve paresthesia following infiltration anesthesia for dental implant placement in the posterior mandible. The pareshesia lasted 5 months postoperatively and subsided spontaneously without any intervention. The patient was successfully restored with fixed partial dental prosthesis without any other complication. This is considered the first report of such complication in patient with GBS after local anesthesia in the oral and maxillofacial region. Possible pathogenic mechanism of the complication and clinical implications are discussed.

Restoration of edentulous sites with dental implants is increasingly becoming a popular choice. Cross-sectional 3D imaging using CBCT provides a superior view of the implant site to help the clinician plan the procedure better. In spite of the advantages, radiation dose remains a concern. The evolution of lower dose protocols is ongoing but whether those acquisition protocols yield comparable diagnostic information is still not well established. The objective of this study was to evaluate the diagnostic efficacy of a low dose, 180˚ rotational CBCT acquisition protocol for evaluating a potential implant site in comparison with a conventional 360˚ rotational acquisition. Ten dentate and partially edentulous dry human skulls were chosen for this study. Each skull was imaged using a 360˚ and a 180˚ rotational acquisition on a J. Morita's Accuitomo CBCT scanner. 82 randomized implant sites, 40 in the maxilla and 42 in the mandible were analyzed. Evaluation of cortical and trabecular bone, proximity to crucial structures such as the inferior alveolar nerve canal and the maxillary sinus, and width of the potential placement site were measured. An oral surgeon and an oral radiologist rated the diagnostic efficacy of the scans by evaluating the above characteristics. Statistical evaluation of the data with linear regression showed significant agreement between both protocol measurements. Kappa analyses yielded a good inter-observer agreement. In this ex-vivo study, there was no significant difference in both the qualitative and quantitate evaluation between the conventional 36 0˚ acquisition protocol and  the modified lower dose 180˚ rotational protocol.