Dental implant and abutment in PEEK: stress assessment in single crown retainers on anterior region.

OBJECTIVE: Stress distribution assessment by finite elements analysis in poly(etheretherketone) (PEEK) implant and abutment as retainers of single crowns in the anterior region. MATERIALS AND METHODS: Five 3D models were created, varying implant/abutment manufacturing materials: titanium (Ti), zirconia (Zr), pure PEEK (PEEKp), carbon fiber-reinforced PEEK (PEEKc), glass fiber-reinforced PEEK (PEEKg). A 50 N load was applied 30o off-axis at the incisal edge of the upper central incisor. The Von Mises stress (σvM) was evaluated on abutment, implant/screw, and minimum principal stress (σmin) and maximum shear stress (τmax) for cortical and cancellous bone. RESULTS: The abutment σvM lowest stress was observed in PEEKp group, being 70% lower than Ti and 74% than Zr. On the implant, PEEKp reduced 68% compared to Ti and a 71% to Zr. In the abutment screws, an increase of at least 33% was found in PEEKc compared to Ti, and of at least 81% to Zr. For cortical bone, the highest τmax values were in the PEEKp group, and a slight increase in stress was observed compared to all PEEK groups with Ti and Zr. For σmin, the highest stress was found in the PEEKc. Stress increased at least 7% in cancellous bone for all PEEK groups. CONCLUSION: Abutments and implants made by PEEKc concentrate less σvM stress, transmitting greater stress to the cortical and medullary bone. CLINICAL RELEVANCE: The best stress distribution in PEEKc components may contribute to decreased stress shielding; in vitro and in vivo research is recommended to investigate this.

Effect of hydroxyapatite nanoparticles coating of titanium surface on biofilm adhesion: An in vitro study.

AIM: To evaluate the adhesion of mono and duospecies biofilm on a commercially available dental implant surface coated with hydroxyapatite nanoparticles (nanoHA). MATERIAL AND METHODS: Titanium discs were divided into two groups: double acid-etched (AE) and AE coated with nanoHA (NanoHA). Surface characteristics evaluated were morphology, topography, and wettability. Mono and duospecies biofilms of Streptococcus sanguinis (S. sanguinis) and Candida albicans (C. albicans) were formed. Discs were exposed to fetal bovine serum (FBS) to form the pellicle. Biofilm was growth in RPMI1640 medium with 10% FBS and 10% BHI medium for 6 h. Microbial viability was evaluated using colony-forming unit and metabolic activity by a colorimetric assay of the tetrazolium salt XTT. Biofilm architecture and organization were evaluated by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). RESULTS: AE surface had more pores, while NanoHA had even nanoHA crystals distribution. Roughness was similar (AE: 0.59 ± 0.07 µm, NanoHA: 0.69 ± 0.18 µm), but wettability was different (AE: Θw= 81.79 ± 8.55°, NanoHA: Θw= 53.26 ± 11.86°; P = 0.01). NanoHA had lower S. sanguinis viability in monospecies biofilm (P = 0.007). Metabolic activity was similar among all biofilms. In SEM both surfaces on C. albicans biofilm show a similar distribution of hyphae in mono and duospecies biofilms. AE surface has more S. sanguinis than the NanoHA surface in the duospecies biofilm. CLSM showed a large proportion of live cells in all groups. CONCLUSIONS: The nanoHA surface reduced the adhesion of S. sanguinis biofilm but did not alter the adhesion of C. albicans or the biofilm formed by both species.

15-Year Retrospective Study on the Success Rate of Maxillary Sinus Augmentation and Implants: Influence of Bone Substitute Type, Presurgical Bone Height, and Membrane Perforation during Sinus Lift.

Objectives: To evaluate the success rate of bone grafts and implants carried out at the Latin American Institute for Research and Dental Education (ILAPEO), considering the following: (i) the different pure bone substitutes (autogenous, xenogeneic, and alloplastic), (ii) the presurgical bone height, and (iii) how the treatment is compromised when membrane perforation occurs during sinus lift in maxillary sinus surgeries. Material and Methods. The initial sample comprised 1040 records of maxillary sinus lifting surgeries. After evaluation, the final sample retained 472 grafts performed using the lateral window technique with a total of 757 implants. The grafts were divided into 3 groups: (i) autogenous bone (n = 197), (ii) xenogenous bovine bone (n = 182), and (iii) alloplastic material (n = 93). One calibrated examiner classified the sample into two groups based on the residual bone height (<4 mm and ≥4 mm) of the area of interest measured on parasagittal sections of tomographic images. Data on membrane perforation occurrences in each group were collected; qualitative variables were described using frequency, expressed as percentages. The Chi-square test was used to analyze the success of the graft types and the survival rate of the implants as a function of the grafted material and the residual bone height. The Kaplan-Meier survival analysis was used to calculate the survival rate of bone grafts and implants according to the classifications adopted in this retrospective study. Results: The success rate of grafts and implants was 98.3% and 97.2%, respectively. There was no statistically significant difference in the success rate among the different bone substitutes (p = 0.140). Only 8 grafts (1.7%) and 21 implants (2.8%) failed. There was a greater success rate for both grafts (96.5%) and implants (97.4%) when the bone height was ≥4 mm. The success rate in the 49 sinuses in which the membrane was perforated was 97.96% for the grafts and 96.2% for the implants. The follow-up periods after rehabilitation ranged from 3 months to 13 years. Conclusions: Within the limitations of the data analyzed in this retrospective study, maxillary sinus lift was a viable surgical technique that enabled implant placement with a predictable long-term success rate, regardless of the type of material used. The presence of membrane perforation did not interfere with the success rate obtained for grafts and implants.

Clinical performance of short and extrashort dental implants with wide diameter: A systematic review with meta-analysis.

STATEMENT OF PROBLEM: Rehabilitation with wide-diameter reduced-length implants has become popular for patients with minimal vertical bone. However, a consensus on the benefits of this approach is lacking. PURPOSE: The purpose of this systematic review with meta-analysis was to evaluate the influence of wide compared with regular diameter on the clinical performance of short (<10 mm) and extrashort (≤6 mm) dental implants used for rehabilitations with single crowns, fixed partial dentures, or both, in the posterior region. MATERIAL AND METHODS: A search in 6 databases was conducted to select randomized controlled trials (RCTs) and nonrandomized controlled trials (N-RCTs). Five meta-analyses were performed, where the risk ratio (RR) was evaluated. The certainty of evidence was evaluated, and the risk of bias was determined from the Joanna Briggs Institute checklist. RESULTS: Fourteen articles were included, 272 wide- and 478 regular-diameter implants. One study presented a low, 3 an unclear, and 11 a high risk of bias. Meta-analyses showed no statistical difference: implant survival, short dental implants in N-RCTs (up to 1 year - RR 1.01 [0.98; 1.03], 1 to 5 years - RR 1.01 [0.94; 1.08], more than 5 years - RR 1.01 [0.97; 1.06]), extrashort dental implants in N-RCTs (RR 1.04 [0.90; 1.20]), RCTs (RR 1.05 [0.88; 1.25]); implant success in N-RCTs (RR 1.01 [0.97; 1.05]); prosthesis success in N-RCTs (RR 1.01 [0.97; 1.05]). CONCLUSIONS: Short and extrashort dental implants with a wide and regular diameter appear to be clinically appropriate options for implant-supported posterior restorations, with high survival, success, and prosthesis success rates.

Performance of complete dentures fabricated with the simplified and the traditional technique: A randomized clinical trial.

STATEMENT OF PROBLEM: The simplified technique has been recommended for the fabrication of removable complete dentures. However, a consensus regarding the performance of the simplified and the traditional techniques is lacking. PURPOSE: The purpose of this randomized clinical trial was to compare the performance of prostheses fabricated with the simplified and the traditional techniques. MATERIAL AND METHODS: Sixty participants were recruited and randomized into 2 groups: traditional technique (control group) and simplified technique (experimental group). The assessments were performed before treatment (baseline) and 2 and 4 months after adaptation to the new complete dentures. The variables evaluated were satisfaction, oral health-related quality of life (OHRQoL) by using the Brazilian version of the OHIP-EDENT, the quality of the prostheses, and, for the functional assessment, the masticatory performance and swallowing threshold. The data were analyzed by the Fisher exact test, the Mann-Whitney test, and the generalized equations estimating (GEE) method. RESULTS: At baseline, the mean ±standard deviation quality of the prostheses was 5.3 ±2.3 for the traditional technique and 4.9 ±2.3 for the simplified technique, and at 4 months, it was 9.3 ±0.9 and 9.1 ±0.9, respectively. For masticatory performance, the mean ±standard deviation X50 at baseline was 5.7 ±1.4 for the traditional technique and 5.7 ±0.9 for the simplified technique, and at 4 months, it was 3.8 ±1.2 and 3.7 ±0.9, respectively. The mean ±standard deviation OHRQoL at baseline was 14.1 ±8.6 for the traditional technique and 12.5 ±9.4 for the simplified technique, and at 4 months, it was 3.2 ±4.3 and 2.6 ±5.1, respectively. The mean ±standard deviation satisfaction at baseline was 9.5 ±3.9 for the traditional technique and 9.3 ±4.2 for the simplified technique; after 4 months, it was 14.8 ±2.0 for both techniques. There was a significant improvement (P<.05) for all variables in the study when comparing them at the baseline to those at the evaluation after provision of new complete dentures. There was no significant difference in all analyzed variables (P>.05) between the 2 techniques for prosthesis fabrication. CONCLUSIONS: The simplified technique appears to be a suitable alternative to the traditional technique for the fabrication of complete dentures, with similar performance.

Influence of diameter in the stress distribution of extra-short dental implants under axial and oblique load: a finite element analysis

Aim: This study evaluated the influence of a wide diameter on extra-short dental implant stress distribution as a retainer for single implant-supported crowns in the atrophic mandible posterior region under axial and oblique load. Methods: Four 3D digital casts of an atrophic mandible, with a single implant-retained crown with a 3:1 crown-to-implant ratio, were created for finite element analysis. The implant diameter used was either 4 mm (regular) or 6 mm (wide), both with 5 mm length. A 200 N axial or 30º oblique load was applied to the mandibular right first molar occlusal surface. The equivalent von Mises stress was recorded for the abutment and implant, minimum principal stress, and maximum shear stress for cortical and cancellous bone. Results: Oblique load increased the stress in all components when compared to axial load. Wide diameter implants showed a decrease of von Mises stress around 40% in both load directions at the implant, and an increase of at least 3.6% at the abutment. Wide diameter implants exhibited better results for cancellous bone in both angulations. However, in the cortical bone, the minimum principal stress was at least 66% greater for wide than regular diameter implants, and the maximum shear stress was more than 100% greater. Conclusion: Extra-short dental implants with wide diameter result in better biomechanical behavior for the implant, but the implications of a potential risk of overloading the cortical bone and bone loss over time, mainly under oblique load, should be investigated

Patient-reported outcome measures and clinical performance of implant-retained mandibular overdentures with stud and ball attachments: A systematic review and meta-analysis.

STATEMENT OF PROBLEM: Evidence regarding the retention system for a mandibular overdenture is important for treatment planning. However, the clinical performance of stud and ball attachments for mandibular overdenture retainers is unclear. PURPOSE: The purpose of this systematic review and meta-analysis was to compare the clinical performance and self-reported patient outcomes of ball and stud attachments as mandibular overdenture retainers. MATERIAL AND METHODS: Randomized (RCTs) and nonrandomized (N-RCTs) controlled clinical trials were selected based on the eligibility criteria. The risk of bias was assessed by using the Cochrane Collaboration Tools, and the certainty of the evidence (COE) by using the grades of recommendation, assessment, development, and evaluation (GRADE) workshop approach. Meta-analyses according to the follow-up period were performed for implant survival, prosthetic maintenance and complications, bleeding on probing (BoP), marginal bone loss (MBL), satisfaction, and oral health-related quality of life (OHRQoL). RESULTS: Thirteen RCTs and 4 N-RCTs were included. Twelve studies presented a high risk of bias. The stud demonstrated a lower risk ratio (RR) (P<.001) for maintenance and complications concerning the need for matrix activation (RR 7.12 [2.65, 19.15]) (very low COE) and new overdentures (RR 2.47 [1.02, 5.96]) (moderate COE), ranging from 1 to 5 years of follow-up. Mean difference (MD) for MBL after 1 (MD 0.40 [0.28, 0.52]; P<.001) and 5 years (MD 0.18 [0.16, 0.20]; P<.001) was higher for ball attachments than that for stud (very low COE) attachments. Stud attachments also improved satisfaction (P<.001) when compared with ball attachments (very low COE). Implant survival rate (high COE), BoP (very low COE), and OHRQoL (low COE) were similar for the attachments. CONCLUSIONS: Stud and ball attachments are clinically appropriate options as mandibular overdenture retainers and are capable of restoring OHRQoL. Nevertheless, the stud showed greater improvement in satisfaction and less prosthetic aftercare and MBL.

Prosthetic complications and quality of life among wearers of mandibular overdenture with the Facility-Equator system.

This longitudinal study aimed to assess the performance of the Facility-Equator system as mandibular overdenture (MO) retainers from a prosthetic perspective during 2 years of loading and to investigate the oral health-related quality of life (OHRQoL) and whether prosthetic events can affect the OHRQoL. Twenty-four patients (68.1 ± 7.51 years) reported their OHRQoL through the Geriatric Oral Health Assessment Index (GOHAI) and Oral Health Impact Profile (OHIP-EDENT) questionnaires before MO loading and after 1 and 2 years of usage. Prosthetic occurrences were recorded during this period. Data were analyzed using the Wilcoxon test, Mann-Whitney test, and Spearman correlation coefficients. Of the 127 prosthetic events that occurred in the first year, the most frequent events were prosthesis adjustments (16.5%), dislodgement of the Equator attachment (14.17%), and O-ring replacement (11.8%). Eighty-seven prosthetic events were recorded in the second year, the most frequent events being prosthesis adjustments (27.6%), O-ring replacement (20.7%), and recapturing the female matrix (11.5%). All domains of the GOHAI and OHIP-EDENT questionnaires exhibited a significant difference (p < 0.05) between the baseline and 1- and 2-year evaluations, except in the Social Disability and Psychological Discomfort domains (p > 0.05) of OHIP-EDENT after 1 year. Complications related to prosthetic maintenance, such as fracturing of the prosthesis, Equator dislodgement, prosthesis rebasing, and new overdenture confection, affect the OHRQoL (p < 0.05), primarily the Physical Pain and Discomfort domains, especially in the first year of MO loading.

Implant-supported crowns with locking taper implant-abutment connection: A systematic review and meta-analysis.

STATEMENT OF PROBLEM: Implant-supported single crowns are more prone to screw loosening than splinted prostheses. Therefore, the locking taper system, which has a screwless abutment, may perform better when associated with this type of rehabilitation. However, systematic reviews on this system are lacking. PURPOSE: The purpose of this systematic review was to evaluate the clinical performance and complications of single crowns retained by the locking taper system. MATERIAL AND METHODS: This systematic review was registered at the International Prospective Register of Systematic Reviews (PROSPERO) under CRD42020189921. An electronic search was made in 5 databases and 3 other sources up to February 2021 to select prospective clinical studies evaluating the performance of single crowns retained by the locking taper system by using the outcomes implant survival, success rate, complications, marginal bone loss (MBL), and prosthesis success rate. Four meta-analyses grouped according to the follow-up intervals were performed. The risk of bias of the selected studies was evaluated by using the RoB 2 checklist for randomized controlled trials (RCTs) and Downs and Black for uncontrolled studies. RESULTS: Twelve studies were included: 9 prospective cohort studies and 3 RCTs. A survival rate of 99% (98% to 99%) and a success rate of 97% (92% to 99%) after 5 years were found. Of the total, 2.6% biological and 2.9% prosthetic complications were described. The prosthesis success rate was 97% (96% to 98%) after 5 years. An average of -0.73 mm (-0.93 to -0.52) was found for the MBL after 5 years. The risk-of-bias assessment showed 2 RCTs with high risk and 1 RCT with low risk of bias. Among uncontrolled studies, 2 were classified as poor and 7 as fair. CONCLUSIONS: Single crowns retained by locking taper implants can be safely indicated based on the high survival and success rates achieved in the long term, the maintenance of bone level stability over time, and the low incidence of complications.

Prosthetic complications and quality of life among wearers of mandibular overdenture with the Facility-Equator system

Abstract This longitudinal study aimed to assess the performance of the Facility-Equator system as mandibular overdenture (MO) retainers from a prosthetic perspective during 2 years of loading and to investigate the oral health-related quality of life (OHRQoL) and whether prosthetic events can affect the OHRQoL. Twenty-four patients (68.1 ± 7.51 years) reported their OHRQoL through the Geriatric Oral Health Assessment Index (GOHAI) and Oral Health Impact Profile (OHIP-EDENT) questionnaires before MO loading and after 1 and 2 years of usage. Prosthetic occurrences were recorded during this period. Data were analyzed using the Wilcoxon test, Mann-Whitney test, and Spearman correlation coefficients. Of the 127 prosthetic events that occurred in the first year, the most frequent events were prosthesis adjustments (16.5%), dislodgement of the Equator attachment (14.17%), and O-ring replacement (11.8%). Eighty-seven prosthetic events were recorded in the second year, the most frequent events being prosthesis adjustments (27.6%), O-ring replacement (20.7%), and recapturing the female matrix (11.5%). All domains of the GOHAI and OHIP-EDENT questionnaires exhibited a significant difference (p < 0.05) between the baseline and 1- and 2-year evaluations, except in the Social Disability and Psychological Discomfort domains (p > 0.05) of OHIP-EDENT after 1 year. Complications related to prosthetic maintenance, such as fracturing of the prosthesis, Equator dislodgement, prosthesis rebasing, and new overdenture confection, affect the OHRQoL (p < 0.05), primarily the Physical Pain and Discomfort domains, especially in the first year of MO loading.

Marginal misfit of heat-pressed milled wax-pattern and CAD/CAM crowns and its effect on stress distribution in implant-supported rehabilitations

Aim: To compare the marginal fit of lithium disilicate CAD/CAM crowns and heat-pressed crowns fabricated using milled wax patterns, and evaluate its effect on stress distribution in implantsupported rehabilitation. Methods: A CAD model of a mandibular first molar was designed, and 16 lithium disilicate crowns (8/group) were obtained. The crown-prosthetic abutment set was evaluated in a scanning electron microscopy. The mean misfit for each group was recorded and evaluated using Student's t-test. For in silico analysis, a virtual cement thickness was designed for the two misfit values found previously, and the CAD model was assembled on an implant-abutment set. A load of 100 N was applied at 30° on the central fossa, and the equivalent stress was calculated for the crown, titanium components, bone, and resin cement layer. Results: The CAD/CAM group presented a significantly (p=0.0068) higher misfit (64.99±18.73 µm) than the heat-pressed group (37.64±15.66 µm). In silico results showed that the heat-pressed group presented a decrease in stress concentration of 61% in the crown and 21% in the cement. In addition, a decrease of 14.5% and an increase of 7.8% in the stress for the prosthetic abutment and implant, respectively, was recorded. For the cortical and cancellous bone, a slight increase in stress occurred with an increase in the cement layer thickness of 5.9% and 5.7%, respectively. Conclusion: The milling of wax patterns for subsequent inclusion and obtaining heat-pressed crowns is an option to obtain restorations with an excellent marginal fit and better stress distribution throughout the implant-abutment set

Influence of Facial Morphology on Masticatory Function and Quality of Life in Elders Using Mandibular Overdentures: 3-Year Results.

Background: Facial types may interfere in the oral health-related quality of life (OHRQoL) and masticatory performance of implant-retained mandibular overdenture (IMO) wearers. Purpose: Investigate the medium-term changes in the masticatory function (MF) and OHRQoL parameters of IMO users, as a function of facial pattern, anteroposterior skeletal discrepancy, and sex. Methods: Forty IMO users, most of them Caucasian (90%) with average age of 69.17 years were classified according to their facial pattern and antero-posterior discrepancy prior to rehabilitation. MF was evaluated by the multiple sieves method to determine the average particle size (X50), heterogeneity (B) and masticatory efficiency (ME, calculated as the percentage of material retained in the 5.6 and 2.8 mm sieves), using Masticatory performance (MP) and swallowing threshold (ST) tests. OHRQoL was measured by applying the dental impact on daily life (DIDL) questionnaire. The data were analyzed by Wilcoxon-paired tests to analyze changes in MF parameters over time, and mixed-effect multilevel regression models were employed to verify differences between groups. Results: Significant changes were still observed in the 3rd year for the ST test with improvements in B for Mesofacial and in time for Dolichofacial individuals, while ME_2.8 deteriorated for Brachyfacial participants. B values of Class I and male individuals improved and brachyfacial individuals still presented worse homogenization (B) than Mesofacial participants in both masticatory tests. Class II and III participants still showed improvements in ME_5.6 and time compared to Class I despite increases in X50. Class II individuals needed less cycles than Class I in the 3rd year. Brachyfacial participants scored lower in the Appearance domain than Mesofacial ones in the 3rd year. Dolichofacial participants and Class III patients scored lower in the Oral Comfort domain than Mesofacial and Class I, respectively. In addition, age influenced the Pain, Oral Comfort and General Performance domains in the 3rd year. Conclusions: Differences in facial morphology continue to influence the MF and OHRQoL outcomes in the 3rd year, and age influenced some OHRQoL domains. Brachyfacial individuals continue to benefit least from rehabilitation with IMO according to masticatory parameters.

Oral candidiasis and denture stomatitis in diabetic patients: Systematic review and meta-analysis.

Here, the prevalence of oral candidiasis and denture stomatitis among diabetic patients compared to healthy ones was summarized through a systematic review with meta-analysis. Medline, Scopus, Web of Science, Lilacs, Cochrane Library, Embase, and the grey literature were searched without restriction, until May 2020. Eligibility criteria were established, data were extracted, and quality assessment was conducted by two trained examiners. Qualitative synthesis was based on the recommendations of Fowkes and Fulton. Two meta-analyses were performed on studies investigating patients with: a) oral candidiasis and b) denture stomatitis. Out of 6034 screened studies, seven were eligible for qualitative and quantitative synthesis; of these, three evaluated oral candidiasis and four evaluated denture stomatitis. Qualitative synthesis showed that the main methodological problems of the studies included sample size, source of controls, matching, and randomization. Diabetic patients had a similar chance of developing oral candidiasis to non-diabetic patients (OR1.40 [0.96; 2.04], p = 0.08, I2 = 94%). However, diabetic patients had a higher chance to present denture stomatitis compared to non-diabetic patients (OR 1.92 [1.42, 2.59] p < 0.0001, I2 = 0%). Therefore, diabetic patients have a higher chance of developing denture stomatitis compared to non-diabetic patients. However, for all analyses, the certainty of the evidence was considered to be very low.

Masticatory function and oral health-related quality of life of patients with atrophic and non-atrophic mandibles using implant-retained mandibular overdentures: 3-year results of a prospective clinical study.

BACKGROUND: Long-term changes in masticatory function, oral health-related quality of life (OHRQoL) and prosthetic complications in implant-retained mandibular overdenture (IMO) wearers as a function of bone atrophy require detailed investigations. OBJECTIVE: Investigating the evolution of masticatory function, OHRQoL and prosthetic occurrences of IMO wearers according to mandibular bone atrophy over 3 years of usage. METHODS: This study evaluated 26 IMO wearers after 2 and 3 years of IMO loading categorised according to mandibular resorption degree into atrophic mandible (AM) and a non-atrophic mandible (NAM) group. Masticatory function was assessed by the Masticatory Performance (MP) and Swallowing Threshold (ST) tests; OHRQoL and satisfaction via the Dental Impact on Daily Living (DIDL) questionnaire; and the prosthetic maintenance requirements and complications were monitored. RESULTS: After the second year, the AM Group performed 32% more cycles (P = .047) than the NAM Group during the ST test. The DIDL questionnaire showed no significant difference for all domains, except for a moderate effect size in the General Performance domain after the third year. AM Group had more prosthetic occurrences (n = 109) than NAM Group (n = 60) in the first year, mainly due to Equator attachment dislodgment. During the third year, NAM Group presented a greater number of events (n = 45) than AM Group (n = 21) due to the greater number of O-ring exchanges. CONCLUSION: Masticatory function and OHRQoL are not related to mandibular bone atrophy until 3 years after IMO rehabilitation. The prosthetic complications profile differs between groups, mainly in the first year.

Do implant-retained mandibular overdentures maintain radiographic, functional, and patient-centered outcomes after 3 years of loading?

OBJECTIVES: Analyzing whether radiographic, functional, and oral health-related quality of life (OHRQoL) outcomes are maintained over 3 years of implant-retained mandibular overdenture (IMO) function and investigating the bite force associations in the 3rd year of function. MATERIAL AND METHODS: A longitudinal clinical study in which 24 IMO users were evaluated during a 3-year follow-up period. Patients' posterior area index, masticatory function, OHRQoL and bite force were assessed. The masticatory function parameter ST_X50 reflects the opening through which 50% of the crushed particles would pass, ST_B describes the homogeneity of the bolus, and the masticatory efficiency parameters ME_5.6 and ME_2.8 represent the % of material retained in the 5.6 and 2.8 mm sieves, respectively. RESULTS: A significant increase in posterior area index (p ≤ .01) was found in all evaluated periods. Minor deteriorations in ST_X50 (p ≤ .01) and ME_5.6 (p ≤ .01) between the 2nd and the 3rd year coincided with improvements in ST_B (p ≤ .01), number of cycles (p ≤ .01), and cycle time (p = .02). The global OHIP-Edent score (p = .02) and the scores in the functional limitation (p = .02), psychological discomfort (p ≤ .01), and handicap domains (p ≤ .01) increased significantly between the 2nd and the 3rd year. Correlations between bite force and cycle time (p = .03) and between posterior area index and ST_X50 (p ≤ .01) and ME_2.8 (p = .02) were also found. CONCLUSION: Changes in posterior area index, masticatory function, and OHRQoL are still ongoing during the 3rd year of IMO function. Bite force and posterior area index influence the masticatory function outcomes in the 3rd year of IMO function.

Discriminating Masticatory Performance and OHRQoL According to Facial Morphology in Complete Denture Wearers: A Single-Center Controlled Study.

PURPOSE: To evaluate the influence of facial type and anteroposterior skeletal discrepancy of complete denture wearers on residual ridge height, masticatory performance, oral health-related quality of life (OHRQoL), and satisfaction levels. MATERIALS AND METHODS: A total of 56 edentulous patients (mean age of 67.1 years) were radiographically evaluated prior to rehabilitation to determine residual ridge height in the maxilla and mandible, facial type, and anteroposterior skeletal discrepancy. Masticatory performance tests with 40 chewing cycles were applied. The Dental Impact on Daily Living questionnaire was used to measure OHRQoL and satisfaction. Data were analyzed with Kruskal-Wallis test and logistic regression. RESULTS: Dolichofacial participants presented with significantly higher bone height than mesofacial and brachyfacial types in the anterior region of the maxilla and mandible and had more mandibular bone than mesofacial types in the premolar region. Class II patients presented significantly higher bone height than Class I participants in the anterior maxilla. Dolichofacial patients performed significantly better than brachyfacial patients in the masticatory performance test. Class I patients achieved more homogenous artificial food trituration than Class III patients (P < .05). High OHRQoL scores were reported in appearance and general performance irrespective of facial type or anteroposterior skeletal discrepancy. CONCLUSION: Dolichofacial patients had superior masticatory performance compared to brachyfacial patients. Class III patients showed a reduced capacity to homogenize the food bolus. Mesofacial, dolichofacial, and Class III patients reported the best perceptions of their OHRQoL. Anteroposterior skeletal discrepancy seems to be the main factor contributing to mastication impairments in totally edentulous patients.

Mapping of inflammatory biomarkers in the peri-implant crevicular fluid before and after the occlusal loading of narrow diameter implants.

OBJECTIVE: To monitor the cytokine release patterns in the peri-implant crevicular fluid (PICF) and to investigate which factors affect the success rate of narrow diameter implants (NDI) during the first year. MATERIAL AND METHODS: Mandibular implant overdentures (IOD) retained by 2 NDI were installed in 16 clinically atrophic edentulous patients. The following parameters were monitored during the first year: (i) peri-implant health parameters (plaque index (PI), calculus presence (CP), gingival index (GI), probing depth (PD) and bleeding on probing (BoP); (ii) cytokine concentrations in the PICF (TNF-α, IL-1ß, IL-6, IL-10); (iii) implant stability quotient (ISQ); (iv) marginal bone level (MBL) and bone level change (BLC); (v) implant success. The insertion torque, bone type, mandibular atrophy, time since edentulism, and smoking habits were also recorded. All data were analyzed using multivariable multilevel mixed-effects regression models. RESULTS: The variability in the TNF-α release patterns temporarily reduced at weeks (w) 8-12, while the IL-1ß concentrations remained low until they peaked at w48 [p < 0.05; + 177.55 pg/µl (+ 96.13 - + 258.97)]. Conversely, IL-10 release decreased significantly at w48 [p < 0.05; - 456.24 pg/µl (- 644.41 - - 268.07)]. The PD and ISQ decreased significantly (p < 0.05) over the follow-up period, while the MBL was stable after w48 with a BLC of 0.12 ± 0.71 mm. The overall success rate was 81.3%, and was influenced by TNF-α, IL-1ß, IL-10, PI, GI, PD, smoking, and time since edentulism. CONCLUSION: Pro- and anti-inflammatory cytokine release was balanced during the first 24 weeks. The GI, smoking, and time since edentulism are the most important factors determining the implant success. CLINICAL RELEVANCE: The study contributes to the understanding of the osseointegration process in a clinically atrophic population rehabilitated with IOD, and highlights the importance of monitoring clinical peri-implant health-related parameters, smoking habit, and time since edentulism to predict implant success rates.

Oral candidiasis and denture stomatitis in diabetic patients: Systematic review and meta-analysis

Abstract Here, the prevalence of oral candidiasis and denture stomatitis among diabetic patients compared to healthy ones was summarized through a systematic review with meta-analysis. Medline, Scopus, Web of Science, Lilacs, Cochrane Library, Embase, and the grey literature were searched without restriction, until May 2020. Eligibility criteria were established, data were extracted, and quality assessment was conducted by two trained examiners. Qualitative synthesis was based on the recommendations of Fowkes and Fulton. Two meta-analyses were performed on studies investigating patients with: a) oral candidiasis and b) denture stomatitis. Out of 6034 screened studies, seven were eligible for qualitative and quantitative synthesis; of these, three evaluated oral candidiasis and four evaluated denture stomatitis. Qualitative synthesis showed that the main methodological problems of the studies included sample size, source of controls, matching, and randomization. Diabetic patients had a similar chance of developing oral candidiasis to non-diabetic patients (OR1.40 [0.96; 2.04], p = 0.08, I2 = 94%). However, diabetic patients had a higher chance to present denture stomatitis compared to non-diabetic patients (OR 1.92 [1.42, 2.59] p < 0.0001, I2 = 0%). Therefore, diabetic patients have a higher chance of developing denture stomatitis compared to non-diabetic patients. However, for all analyses, the certainty of the evidence was considered to be very low.

Influence of Age and Time Since Edentulism on Masticatory Function and Quality of Life in Implant-Retained Mandibular Overdenture Wearers: 1-year Results from a Paired Clinical Study.

PURPOSE: To investigate the influence of age and time since edentulism on masticatory function and quality of life related to oral health (OHRQoL) in totally edentulous patients after implant-retained mandibular overdenture (IMO) loading. MATERIALS AND METHODS: The sample consisted of 33 patients categorized in two age groups (≤ 65 and > 65 years, respectively), and two time since edentulism groups (< 25 and ≥ 25 years). The masticatory function was evaluated through the masticatory performance and swallowing threshold tests before IMO loading, and 1, 3, 6, and 12 months after IMO loading. The OHRQoL was evaluated by applying the Oral Health Impact Profile (OHIP-EDENT) and Geriatric Oral Health Assessment Index (GOHAI) questionnaires, before loading and after 3, 6, and 12 months. Data were subjected to the Mann-Whitney test and Wilcoxon signed-rank test for paired samples. RESULTS: The masticatory performance and swallowing threshold were not influenced by the age nor by time since edentulism, except 6 months after IMO loading when patients ≤ 65 years of age performed the swallowing threshold test in a significantly shorter time with a reduced number of masticatory cycles (P < .05). The masticatory performance and swallowing threshold outcomes showed a gradual improvement up to 12 months, irrespective of the patient categorization. The GOHAI questionnaire scores showed that the OHRQoL was influenced by age in complete denture wearers with a difference between groups in the psychosocial and global domains. The time since edentulism was not affected by the GOHAI scores of complete denture wearers (P < .05). The OHIP-EDENT questionnaire only indicated significant differences as a function of age or time since edentulism between complete denture wearers. Age was associated with significant differences in the physical pain domain outcome, while time since edentulism did not affect only the psychologic discomfort, psychologic inability, and handicap domains. CONCLUSION: Neither the age nor the time since edentulism influenced the masticatory function of IMO-wearing patients. However, IMO significantly improved the masticatory function in totally edentulous patients, and this is more evident for younger patients (≤ 65 years) with a shorter time since mandibular edentulism (< 25 years). The OHRQoL is only influenced by age and time since edentulism in complete denture wearers; IMO treatment eliminates these differences.

Influence of Insertion Torque on Clinical and Biological Outcomes before and after Loading of Mandibular Implant-Retained Overdentures in Atrophic Edentulous Mandibles.

AIM: To evaluate the influence of primary insertion torque (IT) values of narrow dental implants on the peri-implant health, implant stability, immunoinflammatory responses, bone loss, and success and survival rates. METHODS: Thirty-one edentulous patients received two narrow implants (2.9x10mm, Facility NeoPoros) to retain mandibular overdentures. The implants were categorized in four groups according to their IT: (G1) IT > 10 Ncm; (G2) IT ≥ 10Ncm and ≤ 30 Ncm; (G3) IT >30Ncm and < 45Ncm; (G4) IT ≥ 45Ncm, and all implants were loaded after 3 months of healing. The following clinical outcomes were evaluated 1, 3, 6, and 12 months after implant insertion: (i) peri-implant tissue health (PH), gingival index (GI), plaque index (PI), calculus presence (CP), probing depth (PD), and bleeding on probing (BOP); (ii) implant stability quotient (ISQ) by resonance frequency analysis; and (iii) IL-1ß and TNF-α concentration in the peri-implant crevicular fluid. The marginal bone level (MBL) and changes (MBC) were evaluated. The Chi2 test, Kruskal-Wallis test, mixed-effects regression analysis, and the Kendall rank correlation coefficient were used for statistical analysis (α = 5%). RESULTS: G1 presented the highest PD at all evaluated periods. G2 presented higher PI at month 6 and 12. G4 showed increased GI at month 3 and 12 and more CP at month 1 (p=.003). G2 and G4 had higher ISQ values over the study period, while those from G1 and G3 presented lower ISQ values. The IL-1ß concentration increased until month 12 and was independent of IT and bone type; G4 had a higher IL-1ß concentration in month 3 than the other groups (p=.015). The TNF-α release was negatively correlated with IT, and TNF-α release was highest in G1 at month 12. The MBL immediately after surgery and the MBC at month 12 were similar between the groups, and G4 presented a positive MBC at month 12. The survival and success rates were 75% for G1, 81.3% for G2, 64.3% for G3, and 95% for G4. CONCLUSION: The IT did not influence the clinical outcomes and the peri-implant immunoinflammatory responses and was weakly correlated with the narrow dental implants primary stability. The observed success rates suggest that the ideal IT for atrophic fully edentulous patients may deviate from the standardized IT of 32 Ncm.