Four-year assessment of masticatory function in mandibular overdenture wearers: A randomised clinical trial comparing two to four implants to retain the prosthesis.

BACKGROUND: Limited data exist on the mid- to long-term masticatory capacity of mandibular overdenture (IOD) wearers, particularly regarding the use of posterior implants to retention. OBJECTIVES: To periodically evaluate mastication of IOD wearers, comparing the effectiveness of two to four implants to retain the prosthesis. METHODS: In a randomised controlled clinical trial, 20 complete edentulous patients (14 women), aged 51-84 years (mean age 69.1 ± 9.6), received new bimaxillary complete dentures (CD). After adaptation, baseline measurements of masticatory performance (X50) and swallowing threshold were conducted using the sieving method. Patients were then randomly assigned to groups: control (two intra-foraminal regular implants) and experimental (two intra-foraminal regular implants and two extra-short posterior implants) (n = 10 each). After 4 months, implants were splinted, and a new mandibular IOD was fabricated with bar/clip retention. Mastication was reassessed after 6, 12, and 48 months, and data analysed with repeated measures ANOVA and Sidak's post hoc (α = 0.05). RESULTS: Despite a loss of two patients per group, masticatory performance significantly improved after mandibular IOD installation (p = .031) in both groups (p = .670). A second improvement was observed after 6 months (p = .027), with no subsequent changes (p > .05). Swallowing threshold improvements were noted with IOD, and no discernible differences between groups were observed (p > .05). CONCLUSION: Masticatory function significantly improved after mandibular IOD installation, with the number of implants demonstrating minimal influence. CLINICAL TRIAL REGISTRATION: The present study was not registered in a public database, as mandated. It is important to note that the recommendation for registration was initiated in 2017 by the Committee of Medical Journal Editors, while patient inclusion in the research took place in 2016. Given that the data presented in this manuscript cover a follow-up period of up to 4 years post-surgical intervention, delayed registration was not feasible.

Clinical performance of short versus standard dental implants in vertically augmented bone: an overview of systematic reviews.

OBJECTIVE: To answer the question: What do we know so far about the clinical performance of short implants (≤ 7 mm) when compared to standard length implants in vertically augmented bone, as well as which is the overall confidence of the systematic reviews (SRs) about this topic? MATERIALS AND METHODS: An overview of SRs was conducted. The searches were performed in six electronic databases and grey literature. SRs about short (≤ 7 mm) versus standard dental implants performance in vertically augmented bone were included. The assessed outcomes were marginal bone loss (MBL), implant survival (IS), prosthetic (PC) and biological complications (BC), costs, surgical time, and patient satisfaction. AMSTAR 2 was used to evaluate the overall confidence of included SRs. RESULTS: Thirteen SRs were included. Nine of twelve SRs reported a lower MBL for the short implant group. All the included SRs showed no difference in the IS between groups. A higher rate of BC was reported for standard-length implants in four out of five SRs. No differences regarding PC were reported in four of five SRs. Information related to patient preference, cost, and surgery time were underreported. The confidence evaluation of the SRs was stratified as low for five SRs and critically low for eight SRs. CONCLUSIONS: In an overall low-to-very low confidence levels, short implants appear to perform better in the mid-term (up to 5 years) than standard dental implants associated with vertical bone augmentation regarding MBL and BC, but they have a similar performance regarding IS rates and PC. There is an imperative need to improve the methodological quality of SRs, and efforts should focus on conducting RCTs to broaden the knowledge on this topic. CLINICAL RELEVANCE: Short implants could represent a viable, simpler, and less invasive treatment when available bone height is limited.

The role of immediate provisional restorations on implants with a hydrophilic surface: A randomised, single-blind controlled clinical trial.

OBJECTIVES: To compare the radiographic bone changes, clinical parameters and aesthetic outcomes of immediately provisionalised and conventionally restored implants at 12- and 24-months post-implant placement. MATERIAL AND METHODS: In 24 patients, 24 bone level implants with a hydrophilic (SLActive) surface were placed in healed sites and they were either immediately provisionalised with a non-occluding temporary crown (test group) or left without a crown (control group). In both groups, the definitive restoration was placed 16 weeks after implant placement. Clinical and radiographic parameters were calculated at 12- and 24-months post-implant placement, together with implant success/survival rates according to three different sets of criteria. The aesthetic outcome was evaluated through the Papilla Fill Index and the Pink Aesthetic Score. RESULTS: The mean marginal bone loss at 1 year was -0.73 mm (SD 0.83 mm) in the test group and -0.22 mm (SD 0.46 mm) in the control group (p > .05). Whilst 100% survival rate and positive aesthetic outcomes were recorded in both groups, three patients of the test group did not fulfil all success criteria. CONCLUSIONS: Immediate provisionalisation may represent a viable option for the replacement of single missing teeth, with radiographic, clinical and aesthetic results comparable to those of conventionally loaded implants at 2 years of follow-up.

Topical interventions to prevent acute radiation dermatitis in head and neck cancer patients: a systematic review.

PURPOSE: The purpose of the study is to evaluate the effects of pharmacological and non-pharmacological topical controls in the prevention of radiation dermatitis. METHODS: Relevant clinical trials were identified through electronic searching databases CINAHL, CENTRAL, LILACS, PubMed, Scopus, and Web of Science. Handsearching and gray literature searches were also performed to find additional references. Primary outcomes of interest were the development of radiation dermatitis and the time of occurrence of radiation dermatitis. RESULTS: Thirteen randomized clinical trials were included in this review. The trials were published in Chinese, English, or French, from 1980 to 2015. Pharmacological interventions used in the trials were trolamine, aloe vera, allantoin, Lianbai liquid, sucralfate, Na-sucrose octasulfate, olive oil, hialuronic acid, and dexpanthenol. Non-pharmacological topical controls were usual care/institution routine, aqueous cream, mild soap, water thermal gel, placebo, and no intervention. CONCLUSIONS: There was no strong evidence that indicates differences between topical pharmacological interventions or non-pharmacological topical controls in the prevention of acute radiation dermatitis among patients with head and neck cancer undergoing radiotherapy.

Guided bone regeneration in osteoporotic conditions following treatment with zoledronic acid.

OBJECTIVES: To evaluate new bone formation in calvarial critical size defects (CSD) under dense polytetrafluoroethylene (d-PTFE), microporous membranes for guided bone regeneration (GBR) in healthy, osteoporotic and osteoporotic treated with zoledronic acid (ZA) rats. METHODS: Forty-eight, female, 6-month old Wistar rats were included in the study. Osteoporosis was induced by ovariectomy (OVX) and calcium-deficient diet in 32 rats. Sixteen OVX rats were treated with a single dose of Zolendronic Acid (ZA) (OZ), while 16 OVX rats received no treatment (O). The remaining 16 rats were sham-operated and used as healthy controls (C). At 6 weeks following osteoporosis induction, two 5 mm CSD were created in the parietal bones and one of them was treated with a double d-PTFE membrane. The healing periods were 30 and 60 days. New bone formation (NB) was assessed by qualitative and quantitative histological analysis. RESULTS: After 30 days of healing, NB (mean% (95% CI)) was 78.9% (21), 93.1% (9.3) and 84.2% (26.9) in the membrane treated defects and 18.8% (24.1), 27.1% (7.9) and 31% (38.8) in the untreated defects of group O, OZ and C, respectively. After 60 days of healing, NB was 78.3% (14.4), 95.8% (9) and 90.1% (26.1) in the membrane treated defects and 10.8% (17.4), 51.6% (39.4) and 15.7% (12.1) in the untreated defects of group O, OZ and C, respectively. Hierarchical analysis of variance showed that treatment with ZA (P = 0.001) and the use of membrane (P = 0.000) significantly increased new bone formation while presence of osteoporosis may have reduced new bone formation (P = 0.028). CONCLUSION: d-PTFE membranes for GBR promote bone healing in osteoporotic and healthy rats. Treatment with ZA may improve new bone formation in osteoporotic rats.

Prevalence of otologic signs and symptoms in adult patients with temporomandibular disorders: a systematic review and meta-analysis.

OBJECTIVE: This study aims to estimate the prevalence of otologic signs and symptoms in adult patients with temporomandibular disorders (TMD). MATERIAL AND METHODS: Search strategies were developed for each of the following databases: PubMed, LILACS, Scopus, Web of Science, Proquest, LIVIVO, and Google Scholar and OpenGrey was used to assess the grey literature. It was included in this review only observational studies using either research diagnostic criteria (RDC)/TMD or DC/TMD indexes were selected. The Critical Appraisal Checklist for Studies Reporting Prevalence Data from the Joanna Briggs Institute was used to assess the risk of bias of the included studies. A proportion random effects meta-analysis was conducted within the eight included studies. RESULTS: Eight studies met the eligibility criteria and were selected. All of the included studies used the RDC/TMD and report associated otologic signs and symptoms. The studies were clustered into groups based on prevalence for each individual sign or symptom. The most prevalent otologic symptom associated with TMD was ear fullness (74.8 % standard deviation (SD), 43.02 to 96.25 %; n = 50), followed by otalgia (55.1 % SD, 31.78 to 77.30; n = 386), tinnitus (52.1 % SD, 38.43 to 65.74; n = 1293), vertigo (40.8 % SD, 11.29 to 74.72; n = 374), and hearing loss (38.9 % SD, 2.83 to 85.46; n = 744). CONCLUSION: The prevalence of otologic signs and symptoms in adult patients with TMD is high. The most prevalent otologic symptom in patient adults with TMD is ear fullness. CLINICAL RELEVANCE: This study intends to provide understanding over the prevalence of otologic signs and symptoms in TMD cases in adults.

Meta-analysis of single crowns supported by short (<10 mm) implants in the posterior region.

AIM: To assess the failures and complications of short (<10 mm) implants supporting single crowns in the posterior region and its potential risk factors (RkF). MATERIALS AND METHODS: Prospective studies were screened according to eligibility criteria, followed by contact with authors. Quality assessment was performed using a standardized protocol. Mean implant failure proportion (FP), biological and prosthetic failure proportions (BFP/PFP) and marginal bone loss (MBL) including 95% confidence intervals were estimated using random-effects models for meta-analysis. RESULTS: Sixteen studies with a medium methodological quality (mean score: 8 ± 3; 2-14) had data collected. In summary, 762 short implants were followed up for up to 120 months in 360 patients (mean follow-up: 44 ± 33.72 months; mean dropout rate: 5.1%). The means FP, BFP, PFP and MBL were 5.9% (95%CI: 3.7-9.2%), 3.8% (95%CI: 1.9-7.4%), 2.8% (95%CI: 1.4-5.7%) and 0.83 mm (95%CI: 0.54-1.12 mm) respectively. Quantitative analysis showed that placement in the mandible (p = 0.0002) and implants with length ≤8 mm (p = 0.01) increased FP, BFP and MBL, whereas qualitative assessment revealed that crown-to-implant ratio did not influence MBL. CONCLUSIONS: Single crowns supported by short implants in the posterior region are a predictable treatment option with reduced failure rates, biological/prosthetic complications and minimal bone loss.

Long-term clinical performance of short 6-mm implants supporting single crowns in the posterior region: A 10-year cohort study.

INTRODUCTION: Long-term clinical success of non-splinted, posterior, and short implants still is unclear. This prospective cohort study reports the 10-year follow-up of 6-mm implants supporting single crowns in the posterior region, and patient-reported outcomes. METHODS: Baseline sample comprised 20 patients treated with 46 screw-retained crowns supported by 6-mm implants with moderately rough implant surface. Participants were recalled for a 10-year clinical follow-up to assess survival rates, biologic and mechanic conditions, quality of life (OHIP-14), and treatment satisfaction. Data were collected with clinical-radiographic exams and analyzed using descriptive and inferential statistics. RESULTS: Fourteen patients with 35 implant-crown units were examined after 127.6 ± 11.8 months. For the entire cohort period, 7/46 implants were lost (survival estimate: 77.7% at 133 months), and mechanic complications occurred in 14/46 units (survival estimate: 66.4% at 116 months). In the Cox models, "maximum occlusal force" had a significant effect for implant loss (p = 0.038) and for prosthetic screw loosening (p = 0.038); "arch" and "bruxism" were not significant. Peri-implant bone loss was 0.4 ± 0.6 mm at 10 years. For peri-implant bone level, "crown-to-implant ratio" (p < 0.001) and "time" (p = 0.001) were significant. Bone levels differed from baseline to 12, 48, and 120 months. Satisfaction VAS was 94.0 ± 7.9 mm and OHIP-14 was 2.3 ± 2.2. CONCLUSION: Single screw-retained crowns supported by 6-mm implants have an acceptable long-term clinical performance, with stable peri-implant bone levels after 10 years of function.

Alveolar ridge preservation. A systematic review.

OBJECTIVE: The objective of this paper is to examine the effect of alveolar ridge preservation (ARP) compared to unassisted socket healing. METHODS: Systematic review with electronic and hand search was performed. Randomised controlled trials (RCT), controlled clinical trials (CCT) and prospective cohort studies were eligible. RESULTS: Eight RCTs and six CCTs were identified. Clinical heterogeneity did not allow for meta-analysis. Average change in clinical alveolar ridge (AR) width varied between -1.0 and -3.5 ± 2.7 mm in ARP groups and between -2.5 and -4.6 ± 0.3 mm in the controls, resulting in statistically significantly smaller reduction in the ARP groups in five out of seven studies. Mean change in clinical AR height varied between +1.3 ± 2.0 and -0.7 ± 1.4 mm in the ARP groups and between -0.8 ± 1.6 and -3.6 ± 1.5 mm in the controls. Height reduction in the ARP groups was statistically significantly less in six out of eight studies. Histological analysis indicated various degrees of new bone formation in both groups. Some graft interfered with the healing. Two out of eight studies reported statistically significantly more trabecular bone formation in the ARP group. No superiority of one technique for ARP could be identified; however, in certain cases guided bone regeneration was most effective. Statistically, significantly less augmentation at implant placement was needed in the ARP group in three out of four studies. The strength of evidence was moderate to low. CONCLUSIONS: Post-extraction resorption of the AR might be limited, but cannot be eliminated by ARP, which at histological level does not always promote new bone formation. RCTs with unassisted socket healing and implant placement in the ARP studies are needed to support clinical decision making. CLINICAL RELEVANCE: This systematic review reports not only on the clinical and radiographic outcomes, but also evaluates the histological appearance of the socket, along with site specific factors, patient-reported outcomes, feasibility of implant placement and strength of evidence, which will facilitate the decision making process in the clinical practice.

Digital and Analog Analysis of Occlusion in Conventional and Implant-Retained Complete Dentures: Preliminary Results of a Prospective Clinical Trial.

PURPOSE: To digitally evaluate the static and dynamic occlusion of patients treated with both removable conventional complete dentures (CCDs) and implant-retained removable overdentures (IODs) and to correlate two different methods of occlusal analysis. MATERIALS AND METHODS: Eleven totally edentulous patients were treated with bimaxillary CCDs. Later, mandibular CCDs were replaced by IODs retained by either two or four implants. The distribution of the occlusal contacts in static and dynamic occlusion was compared by means of the digital method (DM; T-Scan III) and the analog method (AM; articulating paper). Scores 0, 1, and 2 were assigned for inadequate, satisfactory, and adequate distribution of the occlusal contacts, respectively. The frequencies of scores were compared in relation to the types of denture by means of Fisher exact test (P < .05). The correlation between methods was assessed by means of the kappa agreement coefficient (κ) and the correlation coefficient phi (φ) (P < .05). RESULTS: Significant differences between CCDs and IODs were found in the right lateral mandibular movement (DM, P = .024; AM, P = .008), as well as in the left lateral mandibular movement (DM, P = .035). The methods of analysis of the occlusion showed a moderate agreement (κ = 0.604; P < .001) and a moderate correlation (φ = 0.605; P < .001). CONCLUSION: The digital and analog methods showed a significant agreement and moderate correlation, irrespective of the type of complete denture. The T-Scan III digital system seems to be a consistent and reproducible method to analyze occlusion.

Impact of the extension of the anterior-posterior spread on quality of life and satisfaction of patients treated with implant-retained mandibular overdentures - a randomized clinical trial.

OBJECTIVES: To compare the degree of satisfaction (SD) and the impact on oral health-related quality of life (OHRQoL) of edentulous patients treated with conventional complete dentures (CCDs) and mandibular overdentures (IODs) with a short anteroposterior spread (S-APS) or a large antero-posterior spread (L-APS). MATERIALS AND METHODS: Edentulous patients were treated with CCDs and subsequently randomly allocated to receive a bar clip mandibular overdenture retained by 2 interforaminal implants (Control) or 4 (Test: 2 additional implants distal to the mental foramen). The Oral Health Impact Profile Edent questionnaire (OHIP-20E) and the Visual Analogue Scale (VAS) were applied at a mean follow-up of 38.5 months to assess the impact on OHRQoL and DS, respectively. Comparisons between the type of prosthesis and the extension of the AP spread were made with Student's t test for paired samples and for independent samples, respectively, at a significance level of 5%. RESULTS: The IODs had significantly lower OHRQoL values ​​in the dimensions "functional limitation" (p=0.03), "physical pain" (p=0.02), "psychological discomfort" (p<0.01), "disability physical" (p<0.01) and "general score" (p<0.01) (n=20 patients). The IODs presented DS values ​​significantly for "aesthetics" (p=0.04), "stability" (p=0.03), "masticatory capacity" (p<0.01), "function" (p<0.01) and "oral condition" (p=0.03). The S-APS group (control) resulted in significantly lower values ​​in the dimensions "physical pain" (p<0.01) and "general score" (p<0.01) and no domain with statistical difference in the VAS scale. CONCLUSIONS: IODs significantly improved OHRQoL and DS. The increase in AP spread did not result in benefits for the patient's OHRQOL and DS in this clinical study. (Study Protocol Number: 1.452.492) CLINICAL SIGNIFICANCE: Implantology has experienced in the last 20 years a permanent evolution that aim at increasing predictability and improving long-term clinical performance. Placement of short implants distally to the mental foramen, for instance, and the resulting increase of the anterior-posterior spread, is a promising approach and is worthy of investigation.

Three-dimensional FEA of effects of two dowel-and-core approaches and effects of canal flaring on stress distribution in endodontically treated teeth.

PURPOSE: The aim of this 3D finite element analysis (FEA) was to assess stress distribution and levels in endodontically treated teeth restored with two dowel-and-core systems with differing root canal configurations. MATERIALS AND METHODS: Four 3D finite element models of a laser-digitalized maxillary central incisor embedded in alveolar bone were created. Internal morphology data and mechanical properties of the materials were obtained from the literature. Models included a (1) sound tooth (control) versus an endodontically treated maxillary central incisor with a crown ferrule preparation with two restorative approaches of a ceramic crown over a (2) gold alloy dowel-and-core or (3) glass-fiber dowels with composite cores (4) the latter with a flared root canal. A 100 N static load was applied in the center of the palatal surface at a 45° angle, and the stress distribution pattern was analyzed using ANSYS(®) software. RESULTS: In Model 1 (control), maximum stresses occurred at the coronal third of the buccal (2.32 × 10(7) Pa) and palatal aspects of dentin. The stress peak value of the model (2.45 × 10(7) Pa) occurred on the palatal aspect of the enamel at the level of the cementoenamel junction. With the insertion of dowels with thin cement layers (Models 2 and 3), stress concentrations in radicular dentin decreased, while they increased in the dowel/cement/dentin interface. These models exhibited the greatest stress peak values in the incisal margin of the gold alloy core (18.9 × 10(7) Pa) and in the cement layer (4.7 × 10(7) Pa). In Model 4, stress peak value was observed in the porcelain crown (4.62 × 10(7) Pa), and there was no stress concentration inside the cement layer. CONCLUSIONS: Within the limits of this study, the results suggest that the use of dowels and cements with mechanical properties similar to those of dentin, and an increased cement layer thickness, results in mechanical behavior similar to the physiological behavior of a sound tooth.

Primary and Secondary Stability of Extrashort (4-mm) Implants in the Edentulous Mandible: Preliminary Results of a Prospective Clinical Trial.

PURPOSE: To compare the primary and secondary stability of conventional (≥ 8-mm) and extrashort (4-mm) implants in edentulous patients using different methods of assessment. MATERIALS AND METHODS: Patients underwent implant surgery and were randomly allocated into two groups: test, with two conventional implants in the anterior region and two extrashort (4-mm) implants in the posterior region; and control, with two conventional (≥ 8-mm) implants in the anterior region only. Primary stability (S1-implant placement) was assessed by insertion torque, implant stability quotient (ISQ, Osstell), and damping capacity (PTV, Periotest), while secondary stability (S221-21 days after S1; and S2clip-at prosthetic loading, ± 3 months after S1) was evaluated by ISQ and PTV. The statistical significance level was set at P < .05. RESULTS: Fifty conventional implants and 24 extrashort implants were placed in 25 patients. The overall survival rate was 97.3%. There was no statistically significant difference between the insertion torque of conventional and extrashort implants (P > .05). PTV values were significantly lower for conventional implants only at S2clip (P = .041). ISQ values were significantly greater for conventional implants at S1 (P = .004), whereas at S221 and S2clip, no differences were found (P = .413 and P = .490, respectively). Damping capacity showed no significant differences between S1-S2M21 and S1-S2clip. ISQ values showed a significant increase of stability between S1-S2clip, for conventional (P = .022) and extrashort (P = .005) implants, which was different from that observed between S1-S221. There was a moderate negative correlation between the PTV and ISQ variables (r = 0.5) of extrashort implants, and between the PTV and insertion torque (r = -0.3) of conventional implants. For extrashort implants, there was a null correlation between ISQ and torque (r = 0.0). There was a moderately positive correlation between ISQ and torque (r = 0.3) in the conventional implant group. CONCLUSION: The results suggest that extrashort and conventional implants present similar primary and secondary stability values and may similarly influence restorative protocols.

Adhesion to high-performance polymers applied in dentistry: A systematic review.

OBJECTIVE: The aim of this systemic review, conducted in accordance with the PRISMA statement, was to investigate the impact of surface pretreatments on the bonding strength of high performance polymers (HPPs). METHODS: Eight databases were searched through March 2019. Risk of bias was assessed and random effects meta-analyses were applied to analyze mean differences in shear bond strength (SBS) and tensile bond strength (TBS), considering surface pretreatments and bonding agents after 24h and thermocycling. RESULTS: A total of 235 relevant titles and abstracts were found, yielding 11 final selections. Low risk of bias was observed in most studies. For polyetheretherketone (PEEK) specimens, random-effect models showed that, compared to non-treated controls, pretreatments associated with Visio.link® (Bredent, Senden, GE) increased TBS by 26.72MPa (95% confidence interval (CI), 19.69-33.76; p<0.00001) and increased SBS by 4.86MPa (95% CI, 2.61-7.10; p<0.00001). Air abrasion improved SBS by 4.90MPa (95% CI, 3.90-5.90; p<0.00001) (50µm alumina) and 4.51MPa (95% CI, 1.85-7.18; p=0.0009) (silica-coated CoJet). In comparison to non-treated controls, Visio.link® and Signum PEEK Bond® (Heraeus Kulzer, Hanau, GE) increased SBS by 33.76MPa (95% CI, 18.72-48.81; p<0.00001) and 33.28MPa (95% CI, 17.48-49.07; p<0.00001), respectively. No differences were found between Visio.link® and Signum PEEK Bond® or Monobond Plus/Heliobond® (Ivoclar Vivadent, Schaan, LH) (p>0.05). Similar results were observed for polyetherketoneketone (PEKK) specimens. SIGNIFICANCE: This review shows improved HPP bonding following the application of various surface pretreatments, including air abrasion and bonding agents.

Fixed and Removable Full-Arch Restorations Supported by Short (≤ 8-mm) Dental Implants In the Mandible: A Systematic Review and Meta-Analysis.

PURPOSE: To evaluate, through a systematic review of the literature, the published data regarding marginal bone loss, implant failure proportion, biologic and prosthetic complications, and risk factors associated with short (≤ 8-mm) implants supporting fixed or removable full-arch restorations in the edentulous mandible. MATERIALS AND METHODS: Two reviewers performed a search of five databases, with handsearching through the reference lists and grey literature. Controlled clinical trials and prospective cohort studies were selected in a two-phase process. The data were independently gathered for the same two reviewers. Quality assessment of the studies was done using the Cochrane Handbook for Systematic Reviews of Interventions for Randomized Clinical Trials and the Newcastle-Ottawa Scale for Prospective Cohort Studies. Marginal bone loss and Implant failure proportion were meta-analyzed using random (R-Em) and fixed-effects models (FEm), respectively, with a 95% confidence interval. A descriptive analysis was performed of the prevalence of biologic and prosthetic complications. Meta-regression analysis was run as fixed-effect models for risk factors. RESULTS: Six studies met the eligibility criteria and had data extracted. A total of 291 short implants (lengths 5 to 8 mm) were placed in 122 patients (82 females; mean age, 64.7 ± 10.8) supporting 23 fixed and 99 removable full-arch restorations. The pooled marginal bone loss overall was 0.12 mm (0.07 to 0.17 mm). Marginal bone loss for fixed full-arch restorations was 0.11 mm (0.01 to 0.21 mm) and for removable full-arch restorations was 0.14 mm (0.07 to 0.21 mm). The pooled implant failure proportion was 2.0% (1.0% to 5.0%) for the overall studies. Implant failure proportion for fixed and removable restorations was 2.0% with a confidence interval of (0.0% to 9%) and (0.0% to 6%), respectively. The prevalence of prosthetic complications was 34.5% for fixed restorations and 2.6% for removable restorations. No biologic complications were found for fixed restorations, while 13.1% of removable restorations did have biologic complications. Risk factors did not demonstrate statistical differences regarding Implant failure proportion and marginal bone loss. All included studies demonstrated a high methodological quality. CONCLUSION: Findings from this systematic review and meta-analysis suggest that full-arch restorations supported by short implants in atrophic edentulous mandibles might be a viable treatment option, presenting minimal marginal bone loss and implant failure in the short-term. However, further well-performed prospective clinical trials with long-term observation are needed.

Narrow-diameter implants in the anterior region: A meta-analysis.

PURPOSE: Implants in the anterior region are challenging, and literature reporting outcomes of narrow-diameter implants (NDIs) in anterior sites is scarce. This systematic review summarized evidence of functional and esthetic performance of anterior single crowns supported by NDIs. MATERIALS AND METHODS: Ten databases were searched to find studies evaluating anterior single crowns supported by NDIs. Risk of bias was assessed, and random-effects meta-analyses were applied to analyze mean differences in survival, success, and marginal bone level (MBL). The review was registered in the PROSPERO database (CRD42018089886). RESULTS: Twenty-one studies meeting the screening criteria were included for qualitative analysis, and three for meta-analysis. A total of 892 NDIs, placed in 736 patients, were analyzed. Follow-up duration varied from 12 months to 14 years (mean: 40 months), and 16 failures (implant loss) were recorded. Fixed-effect meta-analysis (I2 = 0%) of survival rate revealed a risk difference of 0.02 (95% CI: -0.03 to 0.08), between NDIs and controls (regular-diameter implants), without differences between groups (P = .39). Success rates ranged from 84.2% to 100% (mean: 95.2%). Random-effects meta-analysis (I2 = 56%) of MBL indicated a mean difference of 0.02 mm (95% CI: -0.21 to 0.25), without differences between groups (P = .87). CONCLUSION: Single crowns supported by NDIs are a predictable treatment, since their survival rate and MBL are comparable to those supported by regular-diameter implants. Due to data shortage reporting esthetic outcomes, more studies are needed to evaluate the long-term performance of the single crowns supported by NDIs in the anterior region.

Relation between insertion torque and tactile, visual, and rescaled gray value measures of bone quality: a cross-sectional clinical study with short implants.

BACKGROUND: This study assessed the relationship between insertion torque and bone quality evaluated during surgery and in preoperative computed tomographic (CT) images analyzed either visually or by rescaled mean gray values (MGVs). The study also tested the correlation between the clinical and radiographic measures of bone quality. METHODS: The consecutive sample was composed of 45 short implants (4.1 × 6 mm) placed in the posterior region of 20 patients. Intra-surgical tactile bone quality, based on the classification of bone types by Lekholm and Zarb, and insertion torque were recorded during the implant placement. Visual bone quality and normalized MGV were assessed in standardized axial, coronal, and sagittal sections of preoperative CT images. Data were analyzed by ANOVA and Spearman correlation (alpha = 0.05). RESULTS: Insertion torque was associated with all assessment methods of bone quality (tactile, CT visual, MGV). A moderate correlation was found among all methods of bone quality, except for CT visual assessment and tactile evaluation. MGVs varied as a function of arch, dental region, insertion torque, and bone types. CONCLUSIONS: The results suggest that bone quality measures affect primary stability as recorded by insertion torque, and the assessment methods are consistently related.

Expression of Cancer Stem Cell Biomarkers in Human Head and Neck Carcinomas: a Systematic Review.

Malignant neoplasms may be composed of several cell groups, including cancer stem cells (CSC). These cells have been related with the capacity of metastasis, relapse and resistance to multiple drugs during chemotherapy. This study aims to identify CSC biomarkers and their expression pattern in human head and neck carcinomas. This study was conducted following the PRISMA checklist. The search for articles was carried out in five databases (PubMed, Scopus, Web of Science, Lilacs and Scielo). The articles found were selected in two phases: 1) reading the titles and / or abstract and 2) reading the full text. At the end, the selected articles were evaluated by QUADAS-2. Most studies evaluated oral neoplastic tissues and, as a control, samples of normal local mucosa. All studies performed immunohistochemistry as a method of immunolocalization and some also applied immunofluorescence. The most commonly used biomarker was CD44. However, other such as Sox2, Oct4, Nestin, Nanog, BMI1, ALDH1, CD133 and CD166 were also found. Several biomarkers were (ALDH1, Sox2, Oct4, ABCB5, AGR2 and TAZ) correlated with clinical characteristics of the tumor, such as staging, tumor size and lymph node metastasis. These data reinforce the CSC theory and favor the use of these biomarkers as possible determinants of prognosis.

The risk of osteonecrosis on alveolar healing after tooth extraction and systemic administration of antiresorptive drugs in rodents: a systematic review.

PURPOSE: There is much concern about the increasing number of patients with medication-related osteonecrosis of the jaw (MRONJ), and many studies have been published in an attempt to understand the pathophysiology of this condition. This study aimed to systematically review the literature on MRONJ arising in rodents under antiresorptive drug therapy after tooth extraction. METHODS: A search of electronic databases, including LILACS, PROQUEST, PubMed, SCOPUS, and the Web of Science. RESULTS: The search resulted in 2319 titles after removing the duplicates, and one paper was identified using the reference list. Ninety-eight full-text papers were then screened for eligibility, resulting in 20 for inclusion in the final qualitative synthesis. The quality of the articles was assessed using the 'ARRIVE' tool. CONCLUSION: Despite the wide heterogeneity of the methodologies used by the authors, the current available evidence suggests that the combination of bisphosphonate and/or denosumab therapy and tooth extraction is associated with osteonecrosis of the jaw in rodents.

Risk factors for single crowns supported by short (6-mm) implants in the posterior region: A prospective clinical and radiographic study.

BACKGROUND: The use of short implants is still not a consensus for challenging clinical situations, such as unfavorable crown-to-implant (C/I) ratio. PURPOSE: This prospective study evaluated the rates of prosthetic complications and implant failure, the mean marginal bone loss of 6-mm dental implants with single crowns in posterior regions and the potential risk factors. MATERIALS AND METHODS: Forty-six dental implants, 6-mm long and 4.1-mm wide, were placed in the posterior region in 20 patients. Patients were clinically and radiographically examined after the restoration with single crowns and on a yearly basis. Potential risk factors (arch, bruxism, maximum bite force, anatomical and clinical C/I ratios, and occlusal table area) were analyzed according to the following outcomes: implant survival, bone loss, and prosthetic complications. RESULTS: The mean follow-up time was 45 ± 9 (16-57) months. There was no early loss of implants. After prosthetic loading, 4 implants were lost (2 in the mandible and 2 in the maxilla; 91.3% survival), and there were 13 prosthetic complications (28.3%), yielding a 65.2% success rate. The frailty term showed a 95% greater chance of loss in the mandible than the maxilla. Mean peri-implant bone loss was of 0.2 ± 0.4 mm, 0.1 ± 0.2 mm, 0.1 ± 0.3 mm, and 0.2 ± 0.4 mm in the first, second, third, and fourth years, respectively, with a mean cumulative loss of 0.3 ± 0.5 mm at 48 months. In the multilevel model, the effects of the clinical C/I ratio and time were significant for bone loss (P < .001). It was estimated that a mean bone loss of 0.1 mm is associated with both a one-unit increase in time (12 months) and a 0.1 increase in the clinical C/I ratio. The other potential risk factors showed no significant relationship with the outcomes. CONCLUSIONS: The 6-mm implants supporting single crowns performed well, but the mandible shows a higher risk of failure. The time and clinical C/I ratio are predictors for bone loss.