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Purpose: To evaluate the performance of fixed complete dental prostheses supported by axial and tilted implants after at least 3 years of follow-up. Materials and Methods: An electronic search plus a hand search up to April 2021 was undertaken. Clinical studies were selected using specific inclusion criteria, independent of the study design. The main outcomes were cumulative implant survival rate, marginal bone level changes, and complications, after ≥ 3 years of follow-up. The difference in outcomes between axial and tilted implants and between the maxilla and mandible was evaluated using meta-analysis and the Mantel-Cox test. Results: Out of 824 articles retrieved, 24 were included. In total, 2,637 patients were rehabilitated with 2,735 full prostheses (1,464 maxillary, 1,271 mandibular), supported by 5,594 and 5,611 tilted and axial implants, respectively. In a range between 3 and 18 years of follow-up, 274 implants failed. The cumulative implant survival rate was 93.91% and 99.31% for implants and prostheses, respectively. The mean marginal bone level change was moderate, exceeding 2 mm in only two studies. Marginal bone loss was significantly lower around axial compared with tilted implants (P < .0001), whereas it was not affected by arch (maxilla vs mandible; P = .17). Conclusion: Fixed complete dental prostheses supported by tilted and axially placed implants represent a predictable option for the rehabilitation of edentulous arches. Further randomized trials are needed to determine the efficacy of this surgical approach and the remodeling pattern of marginal bone in the long term. Keywords: axial implants, immediate loading, mandible, marginal bone loss, maxilla, tilted implants

Common challenges encountered for atrophic maxilla rehabilitation are the inadequate width and height of attached keratinized mucosa (AKM) and shallow vestibular depth. This study presents a buccally displaced palatal (BDP) flap technique to increase the tissue thickness and AKM width at the second-stage surgery and reestablish the correct fornix depth. The peri-implant pocket depths, modified Plaque Index score, modified sulcus Bleeding Index score, and soft tissue recession were evaluated 6 and 12 months after prostheses loading. A total of 52 implants were placed and analyzed, and no implant failures were found. No significant changes in peri-implant parameters were observed between 6 and 12 months, and mean recession was less than 0.2 mm after 12 months. Though this change was statistically significant, it was clinically irrelevant. The results demonstrate that adequately healthy peri-implant soft tissues and substantial dimensional stability of vestibular soft tissues at the 1-year follow-up were achieved with the BDP flap technique. The BDP flap could represent a viable option for increasing the width and the height of AKM and establishing the correct maxillary fornix depth.

Maxillary sinus wall fenestration at the lateral wall or floor of the sinus can result from many potential factors, such as the repair of oro-antral communication, Caldwell-Luc antrostomy, tooth extraction after an endodontic or periodontal infection that eroded the sinus wall, and the combination of sinus pneumatization and alveolar ridge resorption after teeth removal. When sinus wall fenestration is observed on radiographs, it usually indicates adhesion between the sinus membrane and buccal flap, which makes the reentry surgery for subsequent sinus augmentation challenging. To minimize surgical complications in these challenging scenarios, this paper presents a split-flap surgical technique for the management of soft tissue adhesion between the sinus membrane and alveolar mucosa when attempting a lateral window sinus augmentation.

The aim of the present study was to generate an international and multidisciplinary consensus on the clinical management of implant protrusion into the maxillary sinuses and nasal fossae. A total of 31 experts participated, 23 of whom were experts in implantology (periodontologists, maxillofacial surgeons and implantologists), 6 were otolaryngologists and 2 were radiologists. All the participants were informed of the current scientific knowledge on the topic based on a systematic search of the literature. A list of statements was created and divided into three surveys: one for all participants, one for implant providers and radiologists and one for otolaryngologists and radiologists. A consensus was reached on 15 out of 17 statements. According to the participants, osseointegrated implants protruding radiographically into the maxillary sinus or nasal fossae require as much monitoring and maintenance as implants fully covered by bone. In the event of symptoms of sinusitis, collaboration between implant providers and otolaryngologists is required. Implant removal should be considered only after pharmacological and surgical management of sinusitis have failed. Keywords: consensus, dental implants, maxillary sinus, nasal fossae Conflict-of-interest statement: The authors declare there are no conflicts of interest relating to this study.

Aims: Zygomatic implants are successful alternatives to conventional dental implants for oral rehabilitation of patients with severely atrophic maxillae; however, the use of unilateral zygomatic implants needs to be studied further to validate their efficacy. The present investigation aimed to evaluate unilateral zygomatic implant placement in the oral rehabilitation of partially edentulous patients with extremely atrophic maxillary bone and/or previous implant failures. Materials and methods: This retrospective clinical study included patients with partially edentulous maxillae who underwent unilateral zygomatic implant insertion. The primary outcome was implant survival. Intraoperative, postoperative and prosthetic complications were also assessed based on patients’ clinical records. Results: A total of 32 patients (34 zygomatic implants) with a mean age of 60.45 ± 8.74 years (range 47 to 78 years) were included in the study. The mean follow-up period was 34.3 ± 25.5 months, and the overall implant survival rate was 100%. No intraoperative or postoperative complications developed in any of the patients, and no prosthesis failures or complications were recorded. Conclusions: The results indicate that unilateral zygomatic implant insertion for oral rehabilitation of patients with partially edentulous posterior maxillae with severely atrophic bone and/or previous implant failures can be considered a successful alternative to use of conventional dental implants associated with advanced bone grafting procedures. Keywords: maxillary rehabilitation, oral rehabilitation, partially edentulous atrophic maxilla, unilateral zygomatic implants, zygomatic implants Conflict-of-interest statement: The authors declare no potential conflicts of interest with respect to the authorship and/or publication of this article.

Purpose: To assess whether bone grafting is associated with early implant failure (defined as a lack of osseointegration detected prior to functional loading) and to evaluate the association between bone grafting procedures and other risk factors for early implant failure. Materials and methods: Two independent reviewers conducted an electronic search of MEDLINE (via PubMed). Meta-analysis was performed for the odds ratio of bone grafting procedures associated with early implant failure. The Newcastle-Ottawa Scale for cohort studies was used to assess the risk of bias. Results: Of the 231 articles selected for full-text review, 10 were included in the qualitative analysis and for quantitative meta-analysis. An odds ratio of 1.50 (95% confidence interval 1.06–2.13) was recorded for bone grafting procedures associated with early implant failure. Data regarding the association of bone grafting and other risk factors in determining early implant failure were insufficient for quantitative analysis. Conclusions: Within the limitations of this study, a significant positive association was found between bone grafting procedures and early implant failure. The possible negative effect of bone grafting procedures on implant osseointegration should be considered when planning implant therapy. Keywords: alveolar bone grafting, dental implants, early implant failure, meta-analysis, systematic review Conflict-of-interest statement: The authors declare there are no conflicts of interest relating to this study.

Purpose: The aim of this clinical study was to verify the predictability of the rehabilitation of extremely atrophic jaws with immediately loaded short implants and evaluate posterior mandibular regrowth. Materials and methods: A cohort of consecutive fully edentulous patients wearing complete dentures in both arches was enrolled. Periodically, implant survival and prosthetic success were assessed. After informed consent, a subsample of 10 patients who had preoperative CBCT underwent a postoperative CBCT 1 year after immediate implant loading, and 3D superimpositions of pre- and postoperative images were performed. Linear measurements of bone height were performed at two sites in each hemimandible and, on the same sections, bone density according to the qualitative gray values (GVs) was analyzed in an area of 3 mm2 including the cortical mandibular bone. Results: Fifty-nine fully edentulous patients (31 females, 28 males) with Class VI atrophic mandibles according to Cawood and Howell were rehabilitated with the insertion of four to five short implants (4-mm diameter, 7- or 8.5-mm long). Overall, 251 implants were immediately loaded with a fixed hybrid prosthesis. Four patients did not show up for recall visits, bringing the final number down to 55 patients (31 females, 24 males) and 231 implants. In up to 14 years of follow-up, a total of 4 implant failures were recorded (cumulative survival rate, 98.4%). The biologic complications included 9 mucositis (3.9%) and 3 peri-implantitis (1.3%) at implant-level analysis. Mechanical complications involved 9 chippings of the prosthetic restorations (17.0%). In the 10-patient subsample, the analysis showed bone growth (average of 1.2 ± 0.7 mm) in the posterior areas of the mandible. In addition, bone density was found to increase 17% to 27% with reference to the preoperative CBCT. Conclusion: The immediate loading of short implants may represent a feasible therapeutic option for the treatment of fully edentulous patients with severely atrophic mandibles. Bone regrowth in the posterior areas and an increase in bone density of the mandible may occur. Keywords: atrophic mandibles, immediate implant loading, implant survival

Maxillary sinus grafting is generally a safe procedure. However, intraoperative complications, as well as early and late postoperative complications, may occur. Included in the latter group are graft infections that can be triggered by peri-implantitis. The aim of the present study was to report three cases of late maxillary sinus graft infections and to histologically evaluate the effects of peri-implantitis in the grafted area. In peri-implantitis cases in grafted sinuses, the sole removal of the implant along with accompanying debridement of the infected area may not be sufficient to resolve the infection, and a more-aggressive treatment may be necessary.

Purpose: Dynamic navigation is a technique that allows for the placement of dental implants using a computer-guided approach according to preoperative planning. Its accuracy has been assessed in several previous studies. The purpose of this study was to summarize data on implant placement accuracy using dynamic navigation, to synthesize the frequency of intraoperative complications and implant failures, and to compare this technique with static computer-guided surgery and a freehand approach. Materials and methods: Electronic and manual literature searches until December 2019 were performed. The outcome variables were implant placement accuracy using dynamic navigation, accuracy differences between dynamic and static techniques and between dynamic and freehand techniques, intraoperative complications, and implant failures. Random-effects meta-analyses were performed. Results: A total of 32 studies were included; 29 reported accuracy values (2,756 implants), and 10 focused on complications and implant failures (1,039 implants). The pooled mean implant placement errors were 0.81 (95% CI: 0.677 to 0.943) mm at the entry point and 0.910 (95% CI: 0.770 to 1.049) mm at the apical point. The pooled mean vertical and angular deviations were 0.899 (95% CI: 0.721 to 1.078) mm and 3.807 (95% CI: 3.083 to 4.530) degrees. The navigation group showed significantly lower implant placement errors with respect to the freehand technique (P < .01) and similar accuracy values (P ≥ .05) compared with the static technique. The pooled prevalence of failures was 1% (95% CI: 0.00% to 2%). Conclusion: Dynamic navigation provided small implant placement errors, comparable with those obtained using static computer-guided surgery, and can be considered a more accurate technique than conventional freehand surgery. Keywords: accuracy, computer-guided surgery, dental implants, dynamic navigation

This study aimed to evaluate the correlation between soft tissue thickness measured by CBCT and phenotype probing estimation and to assess the thickness cutoffs for each phenotype probing outcome. CBCT was performed with a lip retractor in order to isolate periodontal soft tissues in 10 consecutive patients. Using colored probes, the phenotype was evaluated for all present teeth and recorded as thin, medium, thick, or very thick. The overall correlation between tissue thickness and the phenotype probe score was r = 0.86 (CI: 0.80, 0.90). The correlation was r = 0.90 (CI: 0.81, 0.94) when only maxillary anterior teeth were considered. The obtained cutoffs were 0.83 mm between thin and medium phenotypes, 1.07 mm between medium and thick phenotypes, and 1.24 mm between thick and very thick phenotypes. Thus, a high correlation between tissue thickness and the phenotype probe score was found. Preliminary data on the use of phenotype probes as an evaluation method for gingival thickness were promising.