3-Year Bone Remodeling in Mandibular Overdenture Wearers: Results from an RCT Comparing Immediate vs Conventional Loading Using Cone Beam Computed Tomography.

PURPOSE: To evaluate the circumferential bone level and the morphological changes in posterior mandibular ridge of mandibular overdenture wearers submitted to conventional and immediate loading through cone beam computed tomography (CBCT) at 1 and 3 years. MATERIAL AND METHODS: Twenty participants who received 2 NDI (Facility - 2.9x10 mm) were randomly allocated to the conventional loading (CL: n=10) or immediate loading (IL: n=10) groups. CBCT scans were performed in each group to analyze the vertical (VBL) and horizontal (HBL) bone level around the implants, analyzed together with the posterior bone remodeling of the mandible measured at distances of 5, 10, 15, and 20 mm from the mental foramen (L1-L4). Differences between groups were verified using the student t test at a significance level of 5%. RESULTS: The IL group showed a significantly higher HBL in the first year (P=.028) and a significantly higher VBL in the third year (P=.032), with HBL of -0.22 mm and VBL of -0.59 mm, respectively. After the third year, measurements of the percentage of cortical and medullar height indicated that the IL group presented a significantly higher percentage of cortical bone height (40.1 ± 9.3) compared to the CL group (31.8 ± 5.8) at position L1 (P=.05). No difference was found for posterior ridge remodeling (P>.05). CONCLUSIONS: IL group showed slightly higher values of HBL and VBL, and locally displayed more replacement of medullary by cortical bone. However, circumferential bone level values in the IL group are still clinically acceptable and the posterior resorption rate remained stable after 3 years of function, irrespective of the loading type.

Immediate versus conventional loading of mandibular implant-retained overdentures: a 3-year follow-up of a randomized controlled trial.

OBJECTIVES: There is a scarcity of randomized clinical trials (RCT) that report medium- and long-term results and a lack of consensus in the literature on the predictability of immediately loaded unsplinted narrow diameter implants supporting mandibular overdentures. This RCT compared the performance of conventional (CL) and immediate loading (IL) of mandibular overdentures retained by two narrow-diameter implants for 3 years. MATERIALS AND METHODS: Patients from an RCT treated with CL or IL were invited to attend to 2- and 3-year follow-ups. Clinical, radiographic, functional, and oral health-related quality of life parameters were evaluated. Prosthetic maintenance events, biological complications, and success and survival rates were also recorded. The data were tested by multilevel mixed-effects linear regression analysis and chi-squared tests. RESULTS: The 1-year survival rates of 90% in the CL group and 85% in the IL group were maintained as no implants were lost between 1 and 3 years. The marginal bone loss (MBL) in the IL group was significantly lower after year 3 (-0.04; p < 0.01). Significant changes were found only for the intra-group comparisons in the third year of function: (i) CL and IL presented similar progression of implant stability, MBL, and posterior bone area resorption; (ii) while CL started deteriorating of masticatory function, IL still exhibited functional evolution and (iii) oral comfort domain in the CL and pain domain in the IL were improved. CONCLUSION: Although IL experienced the lowest MBL after 3 years, the outcomes showed that both loading protocols result in predictable medium-term rehabilitation when monitored annually. CLINICAL RELEVANCE: It can be expected that in the third year of function, patients with immediate loading may present more complaints related to general performance even with acceptable masticatory function and self-reported improvements in oral comfort.

Functional performance and impact on the quality of life of three treatment strategies for mandibular edentulism: Results of a parallel 3-group cross-sectional study.

OBJECTIVES: This parallel cross-sectional study compared masticatory function and patient-centered outcomes among 3 removable treatment strategies for mandibular edentulism. METHODS: Thirty-six edentulous participants rehabilitated using 3 removable treatment strategies for mandibular edentulism were allocated to one of the three groups (n=12): CCD (control), 2-IMO, and 3-IMO. Narrow diameter implants were installed using single-stage surgery and conventionally loaded with stud abutments. After 3 months of usage, the quality of life, maximum bite force, and masticatory function were evaluated. Data were analyzed with the Kruskal-Wallis test and post hoc pairwise Mann-Whitney tests with Bonferroni correction (α=0.05). RESULTS: The 2-IMO and 3-IMO wearers did not show significant differences in any outcome, except for the 2 domains of 3-IMO wearers quality of life that obtained better Pain and General Performance scores. Both IMO groups presented significantly higher maximum bite force than CCD wearers. The 2-IMO wearers showed superior outcomes to the CCD group in all outcomes of the masticatory performance test and the X50, B and ME5.6 outcomes of the swallowing threshold test (p = 0.01), while 3-IMO participants only showed superior masticatory performance in terms of lower X50 values (19.86%, p = 0.02) and higher ME 2.8 (141.15%, p = 0.04) than CCD wearers. CONCLUSIONS: Compared to 2-IMO wearers, 3-IMO wearers report superior impact of treatment on daily living activities in the Pain and General Performance domains. 2-IMO and 3-IMO wearers showed no significant differences between them for all evaluated bite force and masticatory function parameters. CLINICAL SIGNIFICANCE: Although overdentures retained by 3 implants (3-IMO) provide biomechanical advantages over those retained by 2 implants (2-IMO), superior clinical and functional effectiveness is not yet proven.

Effect of mandibular bone atrophy on maxillary and mandibular bone remodeling and quality of life with an implant-retained mandibular overdenture after 3 years.

STATEMENT OF PROBLEM: The medium-term effect of an implant-retained mandibular overdenture on bone remodeling in the maxilla and posterior mandible of edentulous patients and the effects on quality of life have not been established. PURPOSE: The purpose of this prospective observational clinical study was to evaluate the 3-year effects of implant-retained mandibular overdentures on oral-health-related quality of life (OHRQoL) and bone remodeling in different regions of the maxilla and mandible in participants with atrophic or nonatrophic mandibles. MATERIAL AND METHODS: Twenty-six edentulous participants received 2 narrow-diameter implants in the anterior mandible. Mandibular bone atrophy was categorized from presurgical panoramic radiographs according to the Cawood and Howell criteria. OHRQoL was assessed by using the OHIP-EDENT questionnaire. Participants were evaluated annually for 3 years to measure the marginal bone loss and bone area of the posterior mandible, and the anterior and posterior regions of the maxilla were assessed annually through panoramic radiographs. The data were analyzed by using a mixed-effects linear regression to estimate time-dependent trends and a mixed-effect linear regression model to verify differences between groups. The Pearson correlation coefficients between bone variables and 3-year OHIP-EDENT outcomes were calculated. RESULTS: In the third year, atrophic participants had a significantly lower marginal bone loss (0.02 mm) than nonatrophic participants (-0.39 mm) (P=.030). Differences were also found in the functional limitation (nonatrophic=1.82 ±1.75, atrophic participants=1.92 ±1.54; P=.018) and handicap domains (nonatrophic=0.36 ±0.54, atrophic participants=0.08 ±0.27; P=.003). For nonatrophic participants, comparisons between baseline and 3-year outcomes showed significant bone resorption as indicated by the area ratio in the anterior maxilla (P=.035), posterior maxilla (P=.022), and posterior mandible (P=.009). Conversely, the bone area of the anterior maxilla (P=.019) decreased in atrophic participants between baseline and year 1, while the bone area of the anterior maxilla and posterior mandible increased (P<.001) between years 1 and 3. Higher effect sizes were observed in the OHRQoL domains of the atrophic participants. CONCLUSIONS: Bone atrophy influenced both the OHRQoL profile and bone remodeling profile in different regions of the mandible and maxilla in mandibular overdenture users. In atrophic participants, bone tissue in both jaws responded positively to overdenture use, with bone apposition after the first year and bone area preservation in the anterior maxilla, posterior mandible, and peri-implant regions after 3 years of follow-up.

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.

Clinical performance of narrow-diameter implants with hydrophobic and hydrophilic surfaces with mandibular implant overdentures: 1-year results of a randomized clinical trial.

OBJECTIVE: To compare peri-implant clinical and radiographic parameters between hydrophilic and hydrophobic narrow dental implants in patients with mandibular implant overdentures for 1 year. MATERIALS AND METHODS: In a randomized, double-blind, split-mouth study with a 1-year follow-up, sixteen edentulous participants received two narrow-diameter implants in the anterior mandibular region with 2 types of surfaces: hydrophobic (Neoporos surface, NS) and hydrophilic (Acqua surface, AS). During the osseointegration period and after loading with mandibular implant overdentures, the outcomes monitored were (i) peri-implant health: early healing index (EHI), visible plaque index (VPI), calculus presence (CP), peri-implant inflammation (PI), probing depth (PD), and bleeding on probing (BOP); (ii) implant stability quotient (ISQ), (iii) crestal bone loss (CBL) and bone level change (BLC); and (iv) implant success and survival rates. RESULTS: The PD in NS implants decreased by 31.78% between 15 and 30 days, while a similar reduction (-31.28%) occurred in the 3rd month in the AS group. The ISQ also decreased significantly during the 1st month in both groups: -10.95% after 7 days in the NS group and -7.46% after 15 days in the AS group. At 12 months, statistically significant differences were not observed; however, the AS surface presented 50.6% smaller CBL and 41.3% smaller BLC values. The success and survival rates were 62.5% for AS implants and 87.5% for NS implants. CONCLUSION: Narrow-diameter implants with hydrophilic and hydrophobic surfaces loaded with mandibular implant overdentures showed no differences in peri-implant healing, stability, and peri-implant bone remodeling in the 1st year of follow-up.

Effect of mandibular residual ridge regularization on peri-implant wound healing when narrow diameter implants are used as overdenture retainers.

STATEMENT OF PROBLEM: Alveolar ridge regularization involves the smoothing and minimal reduction of rough alveolar bone ridge to achieve adequate bone thickness around the implant. The effect of this procedure on peri-implant health is unclear. PURPOSE: The purpose of this clinical study was to evaluate whether bone regularization affects the clinical and biological parameters of peri-implant health when narrow diameter implants are placed as mandibular implant overdenture retainers during initial healing and after occlusal loading. MATERIAL AND METHODS: The need for mandibular ridge regularization in the anterior mandibular region was analyzed before the placement of 2 implants (2.9×10 mm, Facility; Neodent) in 21 participants provided with mandibular overdentures. Primary stability was measured by the insertion torque and implant stability quotient (ISQ). Clinical and biological evaluations measuring the plaque index, presence of calculus, probing depth, bleeding on probing index, gingival index, secondary stability (ISQ), and interleukine-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α) concentrations in peri-implant crevicular fluid were measured during osseointegration on days 7, 15, 30, 60, and 90 and after loading on day 180 after implant placement. Multilevel mixed-effects linear regression analysis and the Kaplan-Meier test were used to analyze the data (α=.05). RESULTS: The ISQ values showed significant differences on days 7 (P<.001) and 15 (P=.002) with higher values and on day 180 (P=.008) with a lower value compared with the baseline value in the ridge regularization group. Additionally, a significant decrease in probing depth was observed on days 60 (P=.008) and 180 (P=.027) compared with that on day 15 after implant placement. In the nonridge regularization group, significant decreases in probing depth were observed on days 30 and 180. Moreover, TNF-α levels in this group were significantly lower on days 30 (P=.001), 60, 90, and 180 (P<.001) when compared with the value on day 7 (P<.001). The ridge regularization group presented with significant differences in TNF-α and IL-1ß levels on days 60 (P=.004) and 30 (P=.007), respectively, when compared with the values on day 7. The ISQ and probing depth in the ridge regularization group were associated with changes in TNF-α and IL-1ß levels; furthermore, bone type, duration of edentulism, and mandibular bone atrophy were correlated with the clinical outcomes and TNF-α release. The implant survival rate was 67% in the nonridge regularization group and 100% in the ridge regularization group. CONCLUSIONS: Mandibular ridge regularization appeared to be beneficial for peri-implant healing during the early stages and after 3 months of occlusal loading in patients with an atrophic ridge, prolonged time since edentulism, and poor bone quality.

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.

Prosthetic aftercare, mastication, and quality of life in mandibular overdenture wearers with narrow implants: A 3-year cohort study.

OBJECTIVES: This cohort study investigated clinical, functional, and quality of life outcomes, along with prosthetic maintenance events in mandibular overdenture (MO) wearers for 3 years. METHODS: Thirty MO wearers with narrow diameter implants (NDIs) and locking taper stud abutments (Facility-Equator system) were annually monitored by registering the visible plaque index (VPI), peri­implant inflammation (PI), calculus presence (CP), probing depth (PD), bleeding on probing (BOP), secondary implant stability (ISQ), marginal bone loss (MBL), masticatory performance and dental impact in daily life (DIDL) questionnaire domains. Multilevel mixed-effects linear regression was performed to analyse changes over time. Chi-square tests were performed to analyse the relationship between the appearance of prosthetic complications and maintenance occurrences. The survival rate of patients with NDIs was calculated using the Kaplan-Meier test. RESULTS: Twenty-six individuals attended all follow-ups, the survival rate of 83.3% in the first year was maintained, and no one implant was lost over the 3-year period. There were significant differences for PD between 1 and 3 years (p ≤ 0.01) and between 2 and 3 years for PI (p ≤ 0.01), GI (p ≤ 0.01), ISQ (p = 0.02), and MBL (p ≤ 0.01). All masticatory performance outcomes showed significant differences (p ≤.01). Prosthetic maintenance events decreased significantly over time. Appearance, general performance, and eating and chewing domains presented high effect sizes. CONCLUSION: Continued changes were observed in the clinical parameters of MO users over the 3-year period. In addition, most functional parameters, except for particle homogenization, improved significantly over time. The positive impact on quality of life is likely related to the significant reduction in prosthetic maintenance events. CLINICAL SIGNIFICANCE: Periodic returns to assess peri­implant tissues and MO maintenance should be performed to ensure the success of rehabilitation to assure improvements in masticatory function and oral health-related quality of life.

Effect of macrogeometry and bone type on insertion torque, primary stability, surface topography damage and titanium release of dental implants during surgical insertion into artificial bone.

This study investigated the influence of implant macrogeometry and bone type on insertion torque (IT), primary stability (ISQ), surface topography damage, and the amount of titanium (Ti) released during insertion. Forty implants with different macrogeometries (Facility - Cylindrical with spiral-shaped threads; Alvim - Tapered with buttress-shaped threads) were inserted into artificial bone types I-II and III-IV. Surface morphology was evaluated by Scanning Electron Microscope (SEM) and roughness parameters with Laser Scanning Confocal Microscopy (LSCM) before and after insertion (AI). Implant macrogeometry was characterized by LSCM. The chemical composition of bone beds was determined by SEM associated with Energy Dispersive X-Ray Spectroscopy. The amount of Ti released was analyzed with Energy Dispersive X-Ray Fluorescence. Alvim had greater IT and ISQ than Facility. Bone types I-II require higher IT of implants. Alvim also had greater internal threads angle, higher initial roughness, and significant reduction of roughness AI, compared to Facility. The functional surface height reduced AI, especially in flank and valley of threads. Height of surface roughness of Alvim and Facility implants was similar AI. Implants surface morphology changes and metallic particles on bone beds were observed after implant insertion, mainly into bone types III-IV. Implants inserted into bone types I-II showed less surface damage. Alvim implants released more Ti (37.52 ± 25.03 ppm) than Facility (11.66 ± 28.55 ppm) on bone types III-IV. The implant macrogeometry and bone types affect IT, ISQ, surface damage, and Ti amount released during insertion. Alvim implants were more wear susceptible, releasing higher Ti concentration during insertion into bone types III-IV.

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.

Clinical Versatility of the Facility-Equator Implant System as Mandibular Overdenture Retainers.

The use of mandibular overdentures (MO) for the rehabilitation of totally edentulous individuals with limited bone availability is widespread and has proven clinical success. Narrow diameter implants (NDI) are available on the market as MO retainers to solve problems related to limited bone availability and bone thickness, providing a low-cost, minimally invasive treatment option. This technique evolved over the years, and changes frequently involved the number of implants used as MO retainers, as the adoption of a smaller number of implants can generate biomechanical disadvantages, contributing to the increased stress in peri-implant tissues, which may accelerate marginal bone loss (MBL), in addition to reducing masticatory capacity and satisfaction with rehabilitation. Some studies pointed out that the use of 3 or more implants as MO retainers improves the biomechanics. Thus, the objective of this study was to report 3 different clinical cases where 3 or more NDI were adopted to retain mandibular overdentures in association with diverse loading protocols: (i) 3 implants adopting conventional loading, (ii) 4 implants using progressive loading, and (iii) 4 implants with hybrid loading. The case with 4 implants and progressive loading showed a slight worsening of masticatory function at 1 year, in addition to a more pronounced MBL compared to other cases, but with improvements in satisfaction and oral health-related quality of life. Thus, NDI can be used as MO retainers with predictability and clinical success, using different numbers of implants and loading protocols.

Evaluation of Bite Force and Masticatory Performance: Complete Denture vs Mandibular Overdenture Users.

This cross-sectional observational study with 24 patients evaluated differences in bite force (BF) and masticatory performance (MP) between conventional complete denture (CCD) and implant mandibular overdenture (IMO) users and the correlation between these variables. The BF test was performed bilaterally with an occlusal force device. During the MP test, patients were asked to chew Optocal particles for 40 cycles. The Shapiro Wilk test was employed to verify the normality of the data, the student t test to identify differences between groups, and Pearson's correlation to investigate interrelationships between variables. A multiple linear regression was subsequently performed via the stepwise method. P values ≤0.05 were considered statistically significant. Unlike IMO users, CCD users presented a significant difference (25.6%) in BF between the dominant and non-dominant chewing side (p=0.04). IMO users presented significantly higher BF (p=0.01) without presenting a dominant side (p=0.38), and also performed significantly better for the following MP parameters: MPX50 values decreased by 27.25% in IMO users (p=0.01), MPB decreased by 48.38% (p=0.01), and ME 5.6 decreased by 53.25% (p=0.02), while ME2.8 increased by 151.57% (p=0.01). The BF and MPX50 in the IMO wearers group were negatively correlated (-0.57; p=0.05); this correlation coefficient was the only parameter included in the multivariate regression model. IMO users have higher BF and better masticatory performance than CCD users, especially in terms of chewed particles size reduction. MP is correlated with a higher BF in IMO users through better particle trituration.

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.

Evaluation of bite force and masticatory performance: complete denture vs mandibular overdenture users

Abstract: This cross-sectional observational study with 24 patients evaluated differences in bite force (BF) and masticatory performance (MP) between conventional complete denture (CCD) and implant mandibular overdenture (IMO) users and the correlation between these variables. The BF test was performed bilaterally with an occlusal force device. During the MP test, patients were asked to chew Optocal particles for 40 cycles. The Shapiro Wilk test was employed to verify the normality of the data, the student t test to identify differences between groups, and Pearson's correlation to investigate interrelationships between variables. A multiple linear regression was subsequently performed via the stepwise method. P values ≤0.05 were considered statistically significant. Unlike IMO users, CCD users presented a significant difference (25.6%) in BF between the dominant and non-dominant chewing side (p=0.04). IMO users presented significantly higher BF (p=0.01) without presenting a dominant side (p=0.38), and also performed significantly better for the following MP parameters: MPX50 values decreased by 27.25% in IMO users (p=0.01), MPB decreased by 48.38% (p=0.01), and ME 5.6 decreased by 53.25% (p=0.02), while ME2.8 increased by 151.57% (p=0.01). The BF and MPX50 in the IMO wearers group were negatively correlated (-0.57; p=0.05); this correlation coefficient was the only parameter included in the multivariate regression model. IMO users have higher BF and better masticatory performance than CCD users, especially in terms of chewed particles size reduction. MP is correlated with a higher BF in IMO users through better particle trituration.

Resumo Este estudo observacional transversal com 24 participantes teve como objetivo avaliar as diferenças na força de mordida (FM) e na PM (performance mastigatória) entre usuários de prótese total convencional (PTC) e de overdenture mandibular (OM) e a correlação entre essas variáveis. O teste de FM foi realizado bilateralmente com um dispositivo de força oclusal. Durante o teste de PM, os pacientes foram solicitados a mastigar uma porção padronizada de Optocal por 40 ciclos mastigatórios. O teste de Shapiro Wilk foi empregado para verificar a normalidade dos dados, o teste T de Student para identificar diferenças entre os grupos e os coeficientes de correlação de Pearson para investigar inter-relações entre variáveis. Uma regressão linear múltipla foi realizada pelo método stepwise. Valores de p≤0,05 foram considerados estatisticamente significantes. Diferentemente dos usuários de OM, os usuários de PTC apresentaram uma diferença significativa (34%) na FM entre o lado dominante e o não dominante (p=0,04). Os usuários de OM apresentaram FM significativamente maior (p=0,01) sem apresentar um lado dominante (p=0,38) e obtiveram PM significativamente melhor nos seguintes parâmetros: os valores de PMX50 diminuíram 27,25% (p=0,01), PMB diminuiu em 48,38% (p=0,01), e EM 5.6 diminuiu 53,25% (p=0,02), enquanto EM2.8 aumentou 151,57% (p=0,01). A FM e PMX50 no grupo de usuários da IMO foram negativamente correlacionados (-0,57;p=0,05); esse coeficiente de correlação foi o único parâmetro incluído no modelo de regressão multivariada. Os usuários da OM possuem maior FM e melhor performance mastigatória do que os usuários de PTC, observados principalmente na redução do tamanho das partículas mastigadas. A PM está correlacionada com um maior FM nos usuários da OM através de uma melhor trituração de partículas.

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.

Immediate vs conventional loading of Facility-Equator system in mandibular overdenture wearers: 1-year RCT with clinical, biological, and functional evaluation.

BACKGROUND: The use of immediate loading (IML) is still poorly explored in elderly patients and implant-retained mandibular overdenture (IMO) wearers. For this reason, more comparisons to conventional loading (CL) are required. PURPOSE: To evaluate the clinical, biological, functional, and oral health-related quality of life (OHRQOL) influence of CL and IML loading on elders wearing IMO retained by the Facility-Equator system up to 1 year after implant installation. MATERIAL AND METHODS: Twenty edentulous patients received two narrow diameter implants in the mandible; the loading type (CL or IML) was randomized. The clinical parameters were monitored along with prosthetic events, marginal bone loss (MBL) and bone level change (BLC), implant stability quotients (ISQ), masticatory performance outcomes, and Interleukin 1 beta (IL-1ß) and tumor necrosis factor alpha (TNF-α) levels in the peri-implant crevicular fluid during the first year of loading. The OHRQoL was assessed via the Oral Health Impact Profile-EDENT questionnaire. Data were analyzed by the Mann-Whitney, χ2 , Wilcoxon paired, and McNemar tests. RESULTS: After 1 year, MBL, BLC and ISQ were statistically identical (P > .05) in the CL and IML groups. The probing depth at 12 months in the CL group (2.19 mm) was higher than in the IML group (1.29 mm; P ≤ .0001). TNF-α was 33.6% higher in the CL group at 6 months (P = .043), while IL-1ß was significantly higher in the IML group up to 6 months. The survival rate was 90% in the CL group and 85% in the IML group; 33 prosthetic events occurred in CL group and 23 in IML group. CONCLUSIONS: After 12 months, both loading protocols are viable and result in similar clinical, biological, functional, and OHRQOL outcomes. However, IML generates better adaptation of the peri-implant tissues, faster improvement in OHRQoL and fewer prosthetic intercurrences than CL.

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.

Relationship Between Masticatory Function Impairment and Oral Health-Related Quality of Life of Edentulous Patients: An Interventional Study.

PURPOSE: To investigate the influence of impaired masticatory function on the oral health-related quality of life of conventional complete denture wearers before and after the transition to implant-retained mandibular overdentures. MATERIALS AND METHODS: Masticatory function and oral health-related quality of life were evaluated in 40 edentulous patients after 3 months of adaptation to complete dentures and after transition to implant-retained mandibular overdentures. Masticatory function was evaluated through the swallowing threshold test with a standardized portion of an artificial test food (Optocal) to determine median particle size (×50) and homogenization index (B). After the test, the masticatory function outcomes were used to categorize patients in 2 groups according to chewing performance: (i) satisfactory or (ii) unsatisfactory. The cutoff value for ×50 was based on a preestablished value of 3.68 mm, whereas for the B index, median values were adopted for categorization. The oral health-related quality of life was analyzed via the Oral Health Impact Profile for Edentulous Adults (OHIP-EDENT) questionnaire. The Mann-Whitney test was used to compare masticatory function outcomes and OHIP-EDENT scores, and associations were checked using the Spearman correlation test and multiple linear regression. RESULTS: Masticatory function was significantly correlated with functional limitation (p = 0.02) and physical disability (p = 0.04) for complete denture wearers with unsatisfactory masticatory function. After the transition to implant-retained mandibular overdentures, only the psychological discomfort domain (p = 0.02) was influenced by the masticatory function category. Multiple linear regression analysis revealed that only the functional limitation domain (p < 0.001) of the complete denture wearers was associated with masticatory function outcomes. CONCLUSIONS: Implant-retained mandibular overdentures eliminate the problems that lead to functional limitations, consequently improving masticatory function and oral health-related quality of life of these individuals; however, patients with unsatisfactory masticatory function after transition to implant-retained mandibular overdentures still experience more psychological discomfort.

Prevalence of risk factors for denture stomatitis in complete denture wearers

Aim: The prevalence of denture stomatitis and the relationship with its risk factors was evaluated via secondary data from 62 complete denture (CD) wearers, between 2015 and 2017. Methods: The data was stored in an Excel database and was analyzed using the statistics software STATA/SE 12.0. A descriptive analysis was performed taking into account a categorization of the clinical variables according to risk factor in 4 domains: CD usage, systemic health, hygiene habits, and usage habits. The association amongst the denture stomatitis and risk factors variables was tested by the Chi-square test and the results were statistically significant at p-values <0.05. Results: The CD wearers participants were composed by a majority of elderly (80.64%) and women (72.78%); with 45.16% having been using the current denture for more than 10 years and another 74.19% related a continuous usage. Diabetes and hypertension were related by 83.87% and 67.74%, respectively, with 87.10% using medication. Although 75.80% reported cleaning their dentures 3 times per day or more, and 59.68% considered their oral hygiene very good, 50% of the complete dentures showed dirtiness and clinical signs of Denture Stomatitis were present in 30.64% of the patients. Despite of the evaluated sample shows many risk factors for the development of the disease, an association between the variables was not observed. Conclusion: Considering the high prevalence of the disease in the studied sample, preventive and educational measures on denture usage and hygiene must be reinforced in order to maintain the oral health of the edentulous patients