Bruxism and dental implants: A systematic review and meta-analysis.

BACKGROUND: Overload from bruxism may affect survival of dental implants. OBJECTIVES: To evaluate implant failure and marginal bone loss (MBL) in patients presenting with probable bruxism compared to non-bruxers. The study was registered in PROSPERO (CRD42021238397). METHODS: An electronic search September 2022 in PubMed/Medline, Web of Science and Science Direct was combined with a hand search. Two independent reviewers carried out abstract screening, full-text assessment, quality assessment (National Institutes of Health tool) and data extraction. Only studies that provided information on self-report and clinical examination needed for the diagnosis of at least 'probable' bruxism were included. A pairwise random-effect meta-analysis was carried out. RESULTS: In total 1338 studies were identified, and after screening and full-text assessment 27 studies that presented data on 2105 implants in probable bruxers and 10 264 implants in non-bruxers were included, with 138 and 352 implant failures in respective groups. the meta-analysis showed that implants placed in probable bruxers had a higher risk of failure than in non-bruxers (OR 2.189; 95% CI 1.337, 3.583, p = .002). A meta-regression showed that follow-up time did not affect this OR. Eighteen studies provided general data on MBL but did not report results separated between bruxers and non-bruxers. Therefore, an analysis of MBL was not possible. CONCLUSION: The results of the present systematic review show that implants placed in probable bruxers present a significantly higher risk of failure than implants placed in non-bruxers. This should be considered in treatment planning and management of implant patients.

Immediate implant placement in the anterior mandible: a cone beam computed tomography study.

BACKGROUND: The placement of implants into the alveolar socket right after tooth extraction is called immediate implant placement (IIP). This approach has its particularities depending on which region of the jaws is involved. The anterior mandible region is peculiar due to the presence of mandibular incisors, which have the shortest roots among all permanent teeth. PURPOSE: This study aimed to investigate the factors that could be associated with the risk of either cortical bone wall perforation or invasion of the 2 mm secure distance from the surrounding anatomical structures (defined as unsafe implant placement), with IIP in the maxillary aesthetic zone, in a cone-beam computed tomography (CBCT) virtual study. MATERIALS AND METHODS: CBCT exams from 239 eligible subjects were investigated. Implants were virtually placed in two distinct positions: prosthetically-driven (along the long axis of the existing tooth) and bone-driven position (according to the available bone and with regard to nearby anatomical structures). Correlation between several variables was tested, and binary logistic regression analysis in order to assess of the possible associations between covariates and unsafe placement was performed. RESULTS: Safe placing implants was significantly higher for the bone-driven in comparison to the prosthetically-driven position (22.2% vs. 3.3%, respectively), and the 2-mm secure distance from anatomical structures was not possible to respect in the majority of cases (77.6% vs. 82.9%, respectively). Covariates associated with a higher risk of unsafe placement were tooth region (CI in relation to IL and CA), decrease of labial concavity angle (LCA), decrease of mandible basal bone height (MBBH), and decrease in mandibular bone thickness at the tooth apex level (MBT0). CONCLUSION: The possibility of safely placing immediate implants in the anterior mandible is significantly higher for bone-driven than in prosthetically driven position. Presurgical virtual planning with CBCT is a great tool for minimizing the risk of implant unsafe placement with regards to the anatomical conditions in the mandible.

Clinical outcomes of tooth-supported monolithic zirconia vs. porcelain-veneered zirconia fixed dental prosthesis, with an additional focus on the cement type: a systematic review and meta-analysis.

PURPOSE: To compare the failure rates and the prevalence of technical complications between full-coverage tooth-supported monolithic zirconia (MZ) and porcelain-veneered zirconia (PVZ) fixed dental prosthesis, based on a systematic literature review. METHODS: An electronic search was performed in three databases, supplemented by hand searching. Several statistical methods were used. RESULTS: Seventy-four publications reported 6370 restorations (4264 PVZ; 2106 MZ; 8200 abutment teeth; 3549 patients), followed up until 152 months. A total of 216 prostheses failed, and survival was statistically significant different between groups. PVZ had higher occurrence of complications than MZ; the difference was especially greater for either minor or major chipping. The difference in prevalence of either minor or major chipping was statistically significant for PVZ prostheses between cementation with glass ionomer and adhesive resin cement (higher), adhesive resin and resin-modified glass ionomer cement (RMGIC, higher), and between RMGIC (higher) and glass ionomer cement. For MZ the difference was significant only for minor chipping between RMGIC (higher) and adhesive resin cement. Abutment teeth to PVZ prostheses more often lost vitality. Decementation was not observed with RMGIC. Air abrasion did not seem to clinically decrease the decementation risk. The 5-year difference in the occurrence of minor or major chipping between MZ and PVZ prostheses was statistically significant, but nor for catastrophic fracture. CONCLUSION: Tooth-supported PVZ prostheses present higher failure and complication rates than MZ prosthesis. The difference in complications is striking when it comes to chipping. CLINICAL RELEVANCE: Awareness of the outcome differences between different types of zirconia prostheses is important for clinical practice.

Marginal bone loss around dental implants: comparison between diabetic and non-diabetic patients-a retrospective clinical study.

OBJECTIVES: The aim of the present retrospective study was to compare the marginal bone loss (MBL) around dental implants in a group of diabetic patients in relation to a matched group of non-diabetic patients. MATERIALS AND METHODS: The present dental record-based retrospective study included patients selected from individuals treated with dental implants at one specialist clinic in Malmö, Sweden. Patients were excluded if they had history of periodontitis and/or were treated for periodontal disease. The study group included 710 implants installed in 180 patients (mean age 60.3±13.0 years), 349 implants in 90 diabetic (21 T1DM and 69 T2DM patients), and 361 implants in 90 non-diabetic patients. RESULTS: The results suggested that jaw (greater MBL in the maxilla), diabetes (greater MBL for diabetic patients, and worse for T1DM patients), bruxism (greater MBL for bruxers), and smoking (greater MBL for smokers and former smokers) had a statistically significant influence on MBL over time. CONCLUSIONS: Patients with diabetes have an estimated greater MBL over time compared to non-diabetic patients. The difference was greater in patients with diabetes type 1 compared to patients with diabetes type 2. Bruxism, smoking, and implant location (maxilla) were also associated with a higher loss of marginal bone around implants over time. CLINICAL RELEVANCE: Awareness of the possible influence of diabetes on the long-term outcomes of dental implant treatment is important, in order to be able to minimize the possibility of a high MBL with time, which can eventually lead to the loss of the implant.

Clinical outcomes of zirconia implants: a systematic review and meta-analysis.

PURPOSE: To assess the clinical outcomes of zirconia dental implants based on an updated systematic literature review. METHODS: An electronic search was performed in three databases, last updated in June 2023, supplemented by hand searching. The eligibility criteria were clinical studies reporting patients rehabilitated with zirconia implants. The cumulative survival rate (CSR) of implants was calculated. A meta-analysis for marginal bone loss (MBL) under different follow-up times and a meta-regression assessing the relationship between mean MBL and follow-up were done. RESULTS: Twenty-five studies were included (4017 implants, 2083 patients). Seven studies had follow-up longer than 60 months. 172 implants failed, after a mean of 12.0 ± 16.1 months (min-max 0.3-86.0), of which 47 early failures, and 26 due to implant fracture, the majority in narrow-diameter implants. The 10-year CSR was 95.1%. Implants with coronal part prepared by drills presented statistically significant lower survival than non-prepared implants (p < 0.001). Two-piece implants presented lower survival than one-piece implants (p = 0.017). Implants discontinued from the market presented lower survival than the commercially available ones (p < 0.001). The difference in survival was not significant between implants in maxilla and mandible (p = 0.637). The mean MBL fluctuated between 0.632 and 2.060 mm over long periods of observation (up until 132 months). There was an estimated MBL increase of 0.005 mm per additional month of follow-up. CONCLUSION: Zirconia implants present high 10-year CSR and short-term low MBL. The review was registered in PROSPERO (CRD42022342055). CLINICAL RELEVANCE: The clinical outcomes observed for zirconia dental implants are very promising, although these have not yet been extensively studied as titanium alloy implants.

Risk Factors Associated with Failure and Technical Complications of Implant-Supported Single Crowns: A Retrospective Study.

Background and Objectives: Implant-supported single crowns have become a routine approach for the replacement of missing single teeth, being considered as one of the most common ways of rehabilitation when adjacent teeth are healthy. The present retrospective study aimed to investigate the risk factors possibly associated with failure and technical complications of implant-supported single crowns and their supporting implants. Materials and Methods: Patients treated at one faculty (2009-2019) were considered for inclusion. Complications investigated included ceramic fracture/chipping, crown loss of retention/mobility, crown failure/fracture, loosening/loss/fracture of prosthetic screw, and implant failure/fracture. Any condition/situation that led to the removal/replacement of crowns (implant failure not included) was considered prosthesis failure. Univariate/multivariate Cox regression models were used to evaluate the associations between clinical covariates and failure. Results: 278 patients (358 crowns) were included. Mean ± SD follow-up was 56.5 ± 29.7 months. Seven implants (after a mean of 76.5 ± 43.7 months) and twenty crowns (21.3 ± 23.5 months) failed. The cumulative survival rate (CSR) for crowns was 93.5% after 5, remaining at 92.2% between 6 and 11 years. The most common reasons for crown failure were porcelain large fracture (n = 6), crown repeatedly loose (n = 6), and porcelain chipping (n = 5). Men and probable bruxism were identified in the Cox regression model as being associated with crown failure. The most common observed technical complications were mobility of the crown and chipping of the ceramic material, with the latter being observed even in crowns manufactured of monolithic zirconia. Cases with at least one technical complication (not considering loss of screw hole sealing) were more common among probable bruxers than in non-bruxers (p = 0.002). Cases of ceramic chipping were more common among bruxers than in non-bruxers (p = 0.014, log-rank test). Conclusions: Probable bruxism and patient's sex (men) were factors associated with a higher risk of failure of implant-supported single crowns.

Comparison of survival outcomes between ameloblastic carcinoma and metastasizing ameloblastoma: A systematic review.

PURPOSE: To investigate and compare the demographic data, occurrence of recurrence and metastasis, and survival prognosis between ameloblastic carcinoma (AC) and metastasizing ameloblastoma (MA), based on appropriate and currently accepted eligible diagnostic criteria, in a systematic review of the literature. METHODS: An electronic search was undertaken, last updated in December 2021. Eligibility criteria included publications having enough clinicopathological information to confirm the diagnosis of these tumors. RESULTS: Seventy-seven publications reporting 85 ACs and 43 MAs were included. Both tumors were more frequent in mandible and showed different clinical profiles regarding patients' sex and age. There was no difference in the estimated cumulative survival between patients diagnosed with these tumors. Metastases mainly affected the lungs, followed by cervical lymph nodes. The mean time between the first metastasis and the last follow-up was higher for MA (p = 0.021). In addition, MA patients remained alive longer than AC patients after the first metastasis diagnosis (p = 0.041). Considering only the cases that metastasized, a higher ratio of AC patients died in comparison to MA patients (p = 0.003). The occurrence of recurrence was associated with a conservative primary treatment with both AC (p < 0.001) and MA tumors (p = 0.017). Multiple recurrent events were associated with conservative primary therapies with MA (p < 0.001) but not with AC (p = 0.121). CONCLUSION: In addition to some demographic differences, ACs that metastasize present a worse prognosis than MA. As conservative procedures are associated with multiple recurrent events, this treatment modality should be avoided for both tumors.

Accuracy evaluation of 3D-printed guide-assisted flapless micro-osteoperforations in the anterior mandible.

AIM: To evaluate the accuracy of tridimensional (3D)-printed guide-assisted flapless cortical bone micro-osteoperforations (MOPs) in the anterior mandible on a cadaver model. MATERIALS AND METHODS: Five human cadaver heads with complete dentition in the anterior mandible were used in the present study. Preplanning CBCT and intraoral surface scans were obtained. After alignment, drilling sites in the interradicular areas were planned from canine to canine, and a surgical guide was printed. The drilling was performed and a postprocedure CBCT scan was obtained to assess the accuracy of the procedure in relation to the virtual planning. RESULTS: The mean ± standard deviation (SD) mesiodistal interradicular space was 2.67 ± 0.84 mm. The mean ± SD error of the actual drilled hole compared with the planned position of the mesial drill site was 0.66 ± 0.33 mm, and to the distal drill site it was 0.56 ± 0.33 mm. There was a statistically significant difference between the number of times the teeth were hit mesially (10 out of 64 holes) and distally (none). CONCLUSIONS: The proposed technique, limited to an ex vivo scenario, provides a valid and reliable method for mandibular MOPs using a 3D-generated surgical guide. However, the risk of damaging adjacent radicular surfaces, particularly in areas with limited mesiodistal interradicular bone, needs to be considered. Further studies should focus on using thinner drills and adding other methods to stabilize the guide. Additionally, by selecting individuals and perforation sites with more mesiodistal interradicular bone, less damage is likely. (Int J Comput Dent 2022;25(4):387-0; doi: 10.3290/j.ijcd.b2599841).

Smoking and Dental Implants: A Systematic Review and Meta-Analysis.

Background and Objectives: Tobacco is today the single most preventable cause of death, being associated with countless diseases, including cancer and neurological, cardiovascular, and respiratory diseases. Smoking also brings negative consequences to oral health, potentially impairing treatment with dental implants. The present review aimed to evaluate the influence of smoking on dental implant failure rates and marginal bone loss (MBL). Materials and Methods: Electronic search was undertaken in three databases, plus a manual search of journals. Meta-analyses were performed, in addition to meta-regressions, in order to verify how the odds ratio (OR) and MBL were associated with follow-up time. Results: The review included 292 publications. Altogether, there were 35,511 and 114,597 implants placed in smokers and in non-smokers, respectively. Pairwise meta-analysis showed that implants in smokers had a higher failure risk in comparison with non-smokers (OR 2.402, p < 0.001). The difference in implant failure between the groups was statistically significant in the maxilla (OR 2.910, p < 0.001), as well as in the mandible (OR 2.866, p < 0.001). The MBL mean difference (MD) between the groups was 0.580 mm (p < 0.001). There was an estimated decrease of 0.001 in OR (p = 0.566) and increase of 0.004 mm (p = 0.279) in the MBL MD between groups for every additional month of follow-up, although without statistical significance. Therefore, there was no clear influence of the follow-up on the effect size (OR) and on MBL MD between groups. Conclusions: Implants placed in smokers present a 140.2% higher risk of failure than implants placed in non-smokers.

KRAS mutations in implant-associated peripheral giant cell granuloma.

OBJECTIVES: To investigate the molecular pathogenesis of implant-associated peripheral giant cell granuloma (IA-PGCG). METHODS: A convenience sample of 15 IA-PGCG cases was selected. Hotspot mutations of KRAS, FGFR1, and TRPV4 genes, previously reported in conventional giant cell lesions of the jaws, were investigated by Sanger sequencing. As these mutations could activate MAPK/ERK pathway, the expression of phospho-ERK1/2 was also evaluated by immunohistochemistry. RESULTS: KRAS mutations were detected in 8/15 (53.4%) samples. Similar to conventional peripheral giant cell granuloma, the KRAS mutations most frequently occurred in codon 146 (p.A146V, n = 3), followed by codon 12 (p.G12A and p.G12D, n = 1 each) and codon 14 (p.V14L, n = 1). Variants of unknown significance (VUS) were also detected in two cases, affecting codons 37 (p.E37K) and 127 (p.T127I). All samples showed wild-type (WT) sequences for FGFR1 and TRPV4 genes. Consistent with MAPK/ERK pathway activation, all mononuclear cells of the lesion showed strong staining for phospho-ERK1/2 protein in the immunohistochemical analysis. CONCLUSIONS: KRAS mutations and activation of the MAPK-ERK signaling pathway occur in IA-PGCG. This is the first study to demonstrate cancer-associated gene mutations in a non-neoplastic reactive condition associated with dental implants.

Dental Implants in Patients with Oral Lichen Planus: A Systematic Review.

Background and Objectives: To integrate the available published data on patients with oral lichen planus (OLP) rehabilitated with dental implants, as well as to review the recommendations for OLP patients receiving implants. Materials and Methods: An electronic search was undertaken in February 2019 using five databases. Publications reporting cases of patients with OLP and rehabilitated with implant-supported oral prosthesis were included. Results: Twenty-two publications were included (230 patients, 615 implants). The overall implant failure rate was 13.9% (85/610). In patients with oral squamous cell carcinoma (OSCC) the failure rate was 90.6% (29/32), but none of these implants lost osseointegration; instead, the implants were removed together with the tumor. One study presented a very high implant failure rate, 76.4% (42/55), in patients with "active lichen planus", with all implants failing between 7-16 weeks after implant placement, and its conflicting and incongruent results are discussed in detail. There was a statistically significant difference between the failure rates in implants installed in different jaws (maxilla/mandible) and when implants of different surfaces were used (turned/moderately rough), but not between patients with reticular or erosive OLP types, or between male and female patients. If OSCC patients and the cases of the latter study are not considered, then the failure rate becomes very low (2.7%, 14/523). The time between implant placement and failure was 25.4 ± 32.6 months (range 1-112). The mean ± SD follow-up was 58.9 ± 26.7 months (1-180). Conclusions: When the results of the one study with a very high failure rate and of the cases that developed OSCC are not considered, the dental implant failure rate in OLP patients was 2.7% after a follow-up of approximately five years. Recommendations are given when treating OLP patients with dental implants.

Adenomatoid odontogenic tumor: An updated analysis of the cases reported in the literature.

PURPOSE: To review the clinical and radiographic features of the available data published on adenomatoid odontogenic tumor (AOT) with special emphasis on the comparison of its variants. METHODS: An electronic search was undertaken in July 2018. Eligibility criteria included publications having enough clinical/radiological/histological information to confirm the diagnosis. RESULTS: A total of 436 publications reporting 1558 cases were included, of which 739 follicular, 247 extrafollicular, and 30 peripheral AOTs. Impacted canine is associated with follicular AOTs in almost 70% of the cases. AOTs were more prevalent in females, in the second decade of life, in maxillae, in anterior region of the jaws, and most are asymptomatic, with a considerable number of lesions presenting cortical bone perforation. Most of the lesions were treated by enucleation. Some cases of recurrence were reported in the literature, but only one was well documented. No difference was found when comparing the clinical/radiological features of the follicular, extrafollicular, and peripheral variants. CONCLUSIONS: Adenomatoid odontogenic tumor variants do not show distinctive clinical radiological features. Recurrence of AOT is very rare, which justify its conservative management.

Clinical factors associated with the recurrence of central giant cell lesions.

Central giant cell lesion of the jaws (CGCLJ) is a destructive condition that shows a varied and unpredictable biological behaviour. In the present study, we aimed to evaluate factors associated with the recurrence of CGCLJ. Based on the data of a previous systematic review of 2270 cases of CGCLJ, we used the multiple imputation to deal with the missing data. The dependent variable was the recurrence after the first treatment (yes/no). The dichotomic covariates were sex, upper or lower jaw location, size (up to or larger than 4 cm), pain, cortical bone perforation (yes/no), locularity (uni-/multilocular), tooth displacement (yes/no), treatment type (curettage or enucleation) and root resorption (yes/no). The final logistic model indicated that the tumours associated with tooth displacement, root resorption and treated with curettage had a more significant chance of recurrence. In conclusion, our study suggests that tooth displacement, root resorption and the type of treatment are potentially useful in the future construction of an algorithm for patient's treatment.

Retrospective clinical evaluation of implant-supported single crowns: Mean follow-up of 15 years.

OBJECTIVE: To retrospectively assess the clinical outcomes of implant-supported single crowns and the supporting implants. MATERIAL AND METHODS: This retrospective study included all patients treated with implant-supported single crowns at one specialist clinic. Implant and prosthesis failure, and mechanical/technical complications (ceramic fracture/chipping; crown loss of retention/mobility; crown failure/fracture; loosening/loss/fracture of prosthetic screw; and implant failure/fracture) were the outcomes analyzed. Any condition/situation that led to the removal/replacement of crowns was considered prosthesis failure. RESULTS: A total of 438 patients with 567 crowns were included. Mean ± SD follow-up of 183.4 ± 69.3 months. A total of 37 implants (6.5%) and 54 crowns (9.5%) failed. If only technical problems were considered, the crown failure rate decreased to 4.1% (23/567). Most common reasons for crown failure: esthetic issue (n = 12), crown constantly mobile (n = 9), change to another type of prosthesis together with other implants (n = 8), crown fracture (n = 7), and crown in infraposition in comparison with adjacent teeth (n = 7). The odds of crown failure were shown to be statistically significantly higher for the following factors: younger patients, maxillary crowns, and screw-retained crowns. Loose prosthetic screw was much more prevalent in screw-retained than in cemented crowns. Ceramic fracture/chipping was more prevalent in screw-retained crowns, maxillae, females. Crown fracture was more prevalent in ceramic crowns, screw-retained crowns, maxillae, posterior region, females. However, these differences were statistically significant only for crown fractures in females. CONCLUSIONS: The odds of crown failure were significant for some factors, but one must keep in mind that non-technical complications are as common as technical ones as reasons for the replacement of implant-supported single crowns.

Ameloblastic fibroma and ameloblastic fibrosarcoma: A systematic review.

PURPOSE: To integrate the available data published to date on ameloblastic fibromas (AF) and ameloblastic fibrosarcomas (AFS) into a comprehensive analysis of their clinical/radiological features. METHODS: An electronic search was undertaken in July 2017. Eligibility criteria included publications having enough clinical, radiological and histological information to confirm a definite diagnosis. RESULTS: A total of 244 publications (279 central AF tumours, 10 peripheral AF, 103 AFS) were included. AF and AFS differed significantly with regard to the occurrence of patients' mean age, bone expansion, cortical bone perforation and lesion size. Recurrence rates were as follows: central AF (19.2%), peripheral AF (12.5%), AFS (all lesions, 35%), primary (de novo) AFS (28.8%) and secondary AFS (occurring after an AF, 50%). Larger lesions and older patients were more often treated by surgical resections for central AF. Segmental resection resulted in the lowest rate of recurrence for most of the lesion types. AFS treated by segmental resection had a 70.5% lower probability to recur (OR 0.295; P = .049) than marginal resection; 21.3% of the AFS patients died due to complications related to the lesion. CONCLUSIONS: Very long follow-up is recommended for AF lesions, due to the risk of recurrence and malignant change into AFS. Segmental resection is the most recommended therapy for AFS.

Peripheral giant cell granuloma: An updated analysis of 2824 cases reported in the literature.

OBJECTIVE: To integrate the available data published on peripheral giant cell granuloma (PGCG) into a comprehensive analysis of its clinical/radiological features. MATERIALS AND METHODS: An electronic search was undertaken in January 2018 in 5 databases, looking for publications reporting cases of PGCGs. Probability of recurrence was calculated for some variables. RESULTS: A total of 165 publications were included, 2824 lesions identified. PGCGs were slightly more prevalent in women and more prevalent in mandibles, usually asymptomatic, and presenting erosion of the subjacent bone in almost one-third of cases. Additional curettage (2.8%) or peripheral osteotomy (0%) after excision presented lower recurrence rates in comparison with excision alone (16%). Excision followed by curettage decreases the probability of recurrence by 85% in comparison with excision alone. Other factors (age, lesion size, follow-up, gender, location, clinical symptoms, bone erosion) seem to do not influence the probability of recurrence. CONCLUSIONS: As surgical excision alone shows a considerable recurrence rate, excision followed by an additional therapy-curettage or peripheral osteotomy-should be the first choice of treatment of PGCG.

Central giant cell lesion of the jaws: An updated analysis of 2270 cases reported in the literature.

PURPOSE: To review all available data published on central giant cell lesion (CGCL) of the jaws into a comprehensive analysis of its clinical/radiological features, with emphasis on the predictive factors associated with its recurrence. METHODS: An electronic search was undertaken in 5 databases (February/2018), looking for reporting cases of CGCLs. RESULTS: A total of 365 publications were included, comprising 2270 lesions. CGCLs were more prevalent in women and the mandible. Cortical bone perforation occurred in 50% of the cases. Marginal/segmental resection was more often performed in larger lesions, and drug therapy was more frequent in small lesions. Recurrence was reported in 232 of 1316 cases (17.6%). The recurrence rate of the aggressive lesions (22.8%) after surgical treatment was higher than non-aggressive lesions (7.8%). Four of 5 CGCLs showed partial/total regression with pharmacological treatment. Aggressive lesions showed a worse response to corticosteroids than non-aggressive lesions. For the lesions submitted to surgery as the first treatment, curettage, enucleation, or marginal resection in relation to segmental resection, aggressive lesions, cortical bone perforation, and tooth root resorption were associated with increased recurrence rate. Recurrence related to a combination of surgical/pharmacological treatment could not be evaluated due to the variety of protocols. CONCLUSIONS: Aggressive CGCLs recur more often than the non-aggressive ones. Despite sometimes showing poor response to corticosteroid injection or surgical curettage, a combination of both treatment strategies should be considered in aggressive cases to reduce morbidities associated with radical surgery. The best protocol to manage aggressive and non-aggressive lesions remains to be determined.

Bruxism and dental implant treatment complications: a retrospective comparative study of 98 bruxer patients and a matched group.

OBJECTIVES: To analyze the complications of dental implant treatment in a group of patients with bruxism in comparison with a matched group of non-bruxers. MATERIAL AND METHODS: Patients being diagnosed as bruxers were identified within a group of patients consecutively treated with implant-supported prostheses at one specialist clinic, based on the most recent listed sign and symptoms of bruxism according to the International Classification of Sleep Disorders. A diagnostic grading system of "possible," "probable," and "definite" sleep or awake bruxism was used, according to a recent published international consensus. A case-control matching model was used to match the bruxers with a group of non-bruxers, based on five variables. Implant-, prosthetic-, and patient-related data were collected, as well as 14 mechanical complications, and compared between groups. RESULTS: Ninety-eight of 2670 patients were identified as bruxers. The odds ratio of implant failure in bruxers in relation to non-bruxers was 2.71 (95% CI 1.25, 5.88). Considering the same number of patients with the same total number of implants equally distributed between groups, the bruxers group had a higher prevalence of mechanical complications in comparison with the non-bruxers group. CONCLUSIONS: This study suggests that bruxism may significantly increase both the implant failure rate and the rate of mechanical and technical complications of implant-supported restorations. Other risk factors may also have influenced the results.

Ameloblastic Fibrodentinoma and Ameloblastic Fibro-Odontoma: An Updated Systematic Review of Cases Reported in the Literature.

PURPOSE: To integrate the available data published on ameloblastic fibrodentinoma (AFD) and ameloblastic fibro-odontoma (AFO) into a comprehensive analysis of its clinical and radiologic features. MATERIALS AND METHODS: An electronic search was undertaken in August 2016. Eligibility criteria included publications reporting cases of AFD or AFO with enough clinical, radiologic, and histologic information to confirm the diagnosis. Demographic data, lesion site and size, treatment approach, and recurrence were analyzed and compared between AFD and AFO. RESULTS: Fifty-four publications reporting on 64 AFDs (60 central, 4 peripheral) and 137 publications reporting on 215 AFOs (211 central, 3 peripheral, 1 unknown) were included. The difference in recurrence rate (when the information about recurrence was provided) was not statistically relevant. The mean age of patients affected by AFD was not statistically different from that of patients affected by AFO. CONCLUSIONS: AFD and AFO presented several similarities: higher prevalence in men and in the mandibles, similar mean age of patients, rate of cortical bone perforation and of the lesions' association with displaced or unerupted teeth and tooth root resorption, mean lesion size, and recurrence rate. The lesions differed in the presence of radiopacities and locularity. Taken together, these data do not support the concept of progressive maturation of these tumoral conditions.

Survival and Complications of Zygomatic Implants: An Updated Systematic Review.

PURPOSE: To assess the survival rate of zygomatic implants (ZIs) and the prevalence of complications based on previously published studies. MATERIALS AND METHODS: An electronic search of 3 databases was performed in December 2015 and was supplemented by manual searching. Clinical series of ZIs were included. Interval survival rate and cumulative survival rate (CSR) were calculated. The untransformed proportion of complications (sinusitis, soft tissue infection, paresthesia, oroantral fistulas) was calculated by considering the prevalence reported in the studies. RESULTS: Sixty-eight studies were included, comprising 4,556 ZIs in 2,161 patients with 103 failures. The 12-year CSR was 95.21%. Most failures were detected within the 6-month postsurgical period. Studies (n = 26) that exclusively evaluated immediate loading showed a statistically lower ZI failure rate than studies (n = 34) evaluating delayed loading protocols (P = .003). Studies (n = 5) evaluating ZIs for the rehabilitation of patients after maxillary resections presented lower survival rates. The probability of presenting postoperative complications with ZIs was as follows: sinusitis, 2.4% (95% confidence interval [CI], 1.8-3.0); soft tissue infection, 2.0% (95% CI, 1.2-2.8); paresthesia, 1.0% (95% CI, 0.5-1.4); and oroantral fistulas, 0.4% (95% CI, 0.1-0.6). However, these numbers might be underestimated, because many studies failed to mention the prevalence of these complications. CONCLUSION: ZIs present a high 12-year CSR, with most failures occurring at the early stages postoperatively. The main observed complication related to ZIs was sinusitis, which can appear several years after ZI installation surgery.