Mandibular overdenture with a single implant in the canine region (c-SIMO): a feasibility study.

OBJECTIVES: The aim of this multi-center pilot study was to assess the viability and feasibility of a novel treatment concept - the canine-positioned single implant mandibular overdenture (c-SIMO), with the single implant placed on the patient's preferred chewing side instead of the midline. MATERIALS AND METHODS: Participants received a single implant in the canine region of their preferred chewing side, based on an Asymmetry Index observed during mastication. The pre-existing mandibular denture was transformed into a c-SIMO on a spherical attachment. The primary outcome was oral health-related quality of life (OHRQoL), measured with GOHAI and OHIP-EDENT. Secondary outcomes included denture satisfaction index (DSI), chewing efficiency (CE), maximum bite force (MBF), implant survival and success, and prosthetic maintenance. Data analysis included descriptive statistics and bivariate comparison tests. RESULTS: Fifteen participants received the c-SIMO treatment (mean age: 69.9 ± 7.0). Implant success and survival rates were 100% at 1 year. Patient-reported outcome measures improved significantly compared to pre-treatment values (OHIP-EDENT: p = 0.001; DSI: p = 0.001; GOHAI: p = 0.002). Masticatory outcomes also improved significantly (CE: p = 0.001; overall MBF: p = 0.005). Post-implant, MBF was significantly higher in the ipsilateral side compared to the contralateral side at 2 weeks (p = 0.019) and 3 months (p = 0.015), but no longer at T3 (p = 0.730). Common prosthodontic events included denture base adjustments (n = 17) and matrix activation (n = 9). CONCLUSIONS: This pilot study concludes that c-SIMO is a promising treatment option, and a potential alternative to the single midline implant overdenture. CLINICAL RELEVANCE: The novel treatment concept of a canine-positioned single implant mandibular overdenture could be a viable treatment alternative to the midline positioning.

A novel test for hyposalivation using a sugar cube.

BACKGROUND: Hyposalivation is a highly prevalent condition in old persons. OBJECTIVES: The aim of this study was to assess a novel tool for the diagnosis of hyposalivation using a sugar cube and to compare its reliability to other validated test methods. METHODS: Five tests were performed: unstimulated salivary flow test by draining method (USFT), oral moisture device Mucus® (MCS), sugar cube test (SCT), stimulated salivary flow test by chewing gum (CG) and Saxon test (SX). The sugar cube test consisted in measuring the time needed to disintegrate a standard-sized sugar cube N°4 (5.6 g) placed beneath the tongue. Bivariate correlation analyses were performed. ROC curve analysis and the Youden Index were used to determine the cut-off value. Sensitivity and specificity were calculated according to the determined cut-off point. RESULTS: A total of 121 participants were recruited, with an average age of 49.8 ± 18.2 years. The USFT was best correlated with the SCT. No correlation was found between SCT and the stimulated saliva tests (CG, SX) as well as the MCS test. According to the Youden index, 140 s is appropriate to diagnose hyposalivation. Sensitivity of .64 and specificity of .91 were found for SCT using USFT as gold standard. The mean subjective evaluation score of the SCT was 3.1 ± 1, significantly higher than USFT 2.6 ± 1.1 (p < .05). CONCLUSIONS: The sugar cube test proved to be a useful method for assessing unstimulated salivation, reducing test execution time and causing less participant discomfort than the gold standard unstimulated salivary flow test.

Single lateral implant for mandibular overdentures as a fallback solution or a viable treatment alternative: Four case reports.

This report of four clinical cases aims to illustrate the use of a lateral implant as a solution for implant overdentures in the mandible in different clinical situations. The first two cases describe the clinical situations of patients wearing two-implant mandibular overdentures until the failure of one of the implants, one due to implant loss and the other due to a fracture of an abutment screw, and how the conditions were managed. The third case illustrates the placement of a single implant to retain an overdenture, where a midline implant, as originally planned, was not feasible due to anatomic reasons. The final case describes the use of a lateral implant to support and retain a single-implant mandibular overdenture. The four cases demonstrate that a single lateral implant can be utilized as sole retention in cases of a failing contra-lateral implant and as an alternative to a single implant in the midline.

Prosthodontic outcomes of mandibular overdenture treatment with one or two implants: 4-year results of a randomized clinical trial.

OBJECTIVE: To assess the incidence of prosthodontic maintenance events and complications during 4 years of follow-up after mandibular overdenture treatment with one or two implants. METHODS: Participants received one or two implants inserted in the midline (1-IOD group) or the lateral incisor-canine area bilaterally (2-IOD group). Implants were loaded with an early loading protocol after 3 weeks. Programmed recall visits were scheduled at the 6-, 12-, 36-, and 48-month follow-ups and nonprogrammed visits in case of prosthodontic complaints. The type of maintenance was registered, and the final treatment outcome was classified as successful, surviving, unknown, dead, repair, or retreatment. RESULTS: Forty-seven participants, mean age 65.4 ± 8.6, 74.5% female, were included (1-IOD = 23; 2-IOD = 24) and 44 completed the 4-year follow-up. A total of 159 prosthodontic maintenance events occurred and 89 in unscheduled visits. The most common event was the need for minor modifications of the denture base due to sore spots in the oral mucosa (n = 56 in 31 patients), matrix activation (n = 54 in 34 patients), and overdenture fracture (n = 25 in 18 patients). A "successful" or "surviving" outcome could be attributed to 57.5% of cases, whereas 38.3% needed repair. No significant differences in the incidence of prosthodontic events or treatment outcomes were found between the two groups. CONCLUSIONS: Findings show that 1-IODs perform similar to 2-IODs when considering the incidence of fractures and the need for prosthodontic maintenance, including adjustments of the overdenture and the attachment system.

Group 4 ITI Consensus Report: Patient benefits following implant treatment in partially and fully edentulous patients.

OBJECTIVES: The aim of Working Group 4 was to address patient benefits associated with implant dentistry. Focused questions on (a) dental patient-reported outcomes (dPROs), (b) improvement in orofacial function, and (c) preservation of orofacial tissues in partially and fully edentulous patients following provision of implant-retained/supported dental prostheses were addressed. MATERIALS AND METHODS: Three systematic reviews formed the basis for discussion. Participants developed statements and recommendations determined by group consensus based on the findings of the systematic reviews. These were then presented and accepted following further discussion and modifications as required by the plenary of the 7th ITI Consensus Conference, taking place in 2023 in Lisbon, Portugal. RESULTS: Edentulous patients wearing complete dentures (CD) experience substantial improvements in overall dPROs and orofacial function following treatment with either complete implant-supported fixed dental prostheses (CIFDP) or implant overdentures (IODs). With respect to dPROs, mandibular IODs retained by two implants are superior to IODs retained by one implant. However, increasing the number of implants beyond two, does not further improve dPROs. In fully edentulous patients, rehabilitation with CIFDP or IOD is recommended to benefit the preservation of alveolar bone and masseter muscle thickness. CONCLUSIONS: Completely edentulous patients benefit substantially when at least the mandible is restored using an CIFDP or an IOD compared to CD. In fully edentulous patients, implant prostheses are the best option for tooth replacement. The availability of this treatment modality should be actively promoted in all edentulous communities, including those with limited access and means.

Design, development and validation of a questionnaire to assess dentists' knowledge and experience in diagnosing, recording, and managing root caries.

OBJECTIVES: The prevalence of root caries is increasing globally, especially in the elderly population, and even though the number of patients with root caries lesions is augmenting, there are still many discrepancies in how dentists manage this condition. The present study aimed to develop and validate a questionnaire to evaluate how dentists diagnose, record and manage root caries lesions, and to verify the validity and reliability of this questionnaire. MATERIALS AND METHODS: An expert panel developed a self-administered questionnaire survey with three domains: (1) dentists' knowledge on diagnosis, recording, and managing root caries; (2) information about their current general clinical routines; (3) their demographics. The original English [E] version was translated into three different languages (French [F], German [G], Italian [I]), and subsequently back-translated into English by independent dentists. For the validation, 82 dentists (20-22 for each of the translated versions) accepted to answer the questionnaire at two different time-points (with 1-week interval). The data was quality checked. Construct validity, internal reliability, and intra-class correlation (ICC) were assessed. RESULTS: Seventy-seven dentists completed the questionnaire twice [E: 17; F: 19; G: 19; I: 22]. The mean ICC (standard deviation) was 0.98(0.03) for E, 0.90(0.12) for F, 0.98 (0.04) for G, and 0.98 (0.01) for I. Overall, the test-retest reliability was excellent (mean ICC (SD): 0.96 (0.08)). Furthermore, the questionnaire demonstrated good internal reliability (inter-observer reliability; Fleiss kappa: overall:0.27(fair); E:0.30 (fair); F: 0.33(fair); G: 0.33(fair); I: 0.89 (almost perfect)). CONCLUSION: The questionnaire was validated and is suitable to be used in the four languages to assess the knowledge of dentists on diagnosing, recording and managing root caries. CLINICAL SIGNIFICANCE: The present questionnaire was validated and seems to be a good tool to evaluate how dentists diagnose, record, and manage root caries lesions both in its original (English) and its translated (French, German, and Italian) versions.

Three tests to determine a preferred chewing side in partially edentulous patients: A pilot study.

STATEMENT OF PROBLEM: Determining the preferred chewing side may be an important factor in prosthetic treatment planning, especially where additional support for a removable dental prosthesis can be provided by implants. PURPOSE: The purpose of this clinical study was to investigate the validity and reproducibility of 3 different tests to determine the preferred chewing side. MATERIAL AND METHODS: A total of 82 partial denture wearers, with an average age of 70 years, were enrolled in this study. The first test (CG) evaluated the left or right position of a piece of chewing gum after spontaneous mouth opening during mastication. A second test (ASI) videotaped 30 seconds of mastication and analyzed the distribution of masticatory cycles by means of an asymmetry index. For the third test (VAS), participants were asked to mark their subjective perception of their preferred chewing side on a visual analog scale representing the right and left sides. All the tests were performed and repeated in a randomized sequence. The reproducibility of the tests was first evaluated. The mean values of the ASI and VAS tests were calculated, and the results were compared with the second series of the CG test. The Pearson correlation test was used to associate ASI and VAS, and the Cohen kappa agreement was used for the inter-reliability of CG (α=.01). RESULTS: The results indicated fair to almost perfect reproducibility for the 3 tests. Kappa values were.37 (P<.01) for the CG,.47 (P<.01) for the ASI and.91 (P<.01) for the VAS. Correlation coefficients resulted in rho=.86 (P<.01) for the ASI and rho=.97 (P<.01) for the VAS. The correlation between ASI and VAS was excellent, with rho=.85 (P<.010). CG and ASI (test kappa=.36, P<.010) and CG and VAS (test kappa=.39, P<.010) showed fair agreement. CONCLUSIONS: ASI and VAS seem more reliable than CG to determine a patient's preferred chewing side and might be helpful within the context of prosthetic treatment planning, where additional support may improve denture function.

Exploring preferences of older adults for dental services: A pilot multi-national discrete choice experiment.

OBJECTIVES: To pilot an exploration of older adults' future preferences using discrete choice experiments to understand who should provide dental examinations and treatment, where these services should be provided, and participants' willingness to pay and willingness to travel. BACKGROUND: The proportion of older adults in the general population is increasing and is recognised as a pressing public health challenge. MATERIALS AND METHODS: Older people aged 65 years and over were recruited into this study from the UK, Switzerland and Greece. Drawing on earlier stakeholder engagement, a set of choice experiments are developed to explore the future preferences of older people for dental examinations and dental treatment, as they anticipated losing their independence. These were presented to the participants using a range of platforms, because of the COVID pandemic. Data were analysed in STATA using a random-effects logit model. RESULTS: Two hundred and forty-six participants (median age 70 years) completed the pilot study. There was a strong preference across all countries for a dentist to undertake a dental examination (Greece: ß = 0.944, Switzerland: ß = 0.260, UK ß = 0.791), rather than a medical doctor (Greece: ß = -0.556, Switzerland: ß = -0.4690, UK: ß = -0.468). Participants in Switzerland and the UK preferred these examinations to be undertaken in a dental practice (Switzerland: ß = 0.220, UK: ß = 0.580) while participants in Greece preferred the dental examination to be undertaken in their homes (ß = 1.172). Greek participants preferred dental treatment to be undertaken by a specialist (ß = 0.365) in their home (ß = 0.862), while participants from the UK and Switzerland preferred to avoid any dental treatment at home (Switzerland: ß = -0.387; UK: ß = -0.444). Willingness to pay analyses highlighted that participants in Switzerland and the UK were willing to pay more to ensure the continuity of future service provision at a family dental practice (Switzerland: ß = 0.454, UK: ß = 0.695). CONCLUSION: Discrete choice experiments are valuable for exploring older people's preferences for dental service provision in different countries. Future larger studies should be conducted to further explore the potential of this approach, given the pressing need to design services that are fit for purpose for older people. Continuity of dental service provision is considered as important by most older people, as they anticipate losing their dependence.

Fit and retention of complete denture bases: Part II - conventional impressions versus digital scans: A clinical controlled crossover study.

STATEMENT OF PROBLEM: Although the intraoral scanning of edentulous ridges is feasible, clinical evidence that the resulting denture retention is equivalent to that achieved with conventional impressions is lacking. PURPOSE: The purpose of this clinical study was to determine the retention of complete denture bases fabricated from digital intraoral scans versus conventional impressions by using border molding and posterior palatal seal compression. MATERIAL AND METHODS: Twenty volunteers with an edentulous maxilla were recruited. An intraoral scan of the maxilla and a conventionally border-molded impression with a custom tray were made. The conventional impression was poured; the definitive cast was scanned. Three-dimensionally (3D) printed (PB1) and milled bases (MB1) were fabricated based on the scan of the definitive cast. Based on the intraoral scan, a 3D-printed (PB2) and a milled base (MB2) were fabricated. On each base, a platform with a hook consisting of a central notch orienting the force against the post dam (PD) and 2 lateral notches orienting the forces against the left (LT) and right (RT) tuberosities was set in the center of the outer surface of the base. A traction dynamometer was inserted in the hook and oriented into the corresponding notch by applying force until dislodgement. All bases were subsequently stored in artificial saliva for 2 weeks and scanned. Retention testing was repeated by using the same procedure. To evaluate trueness and to visualize the differences on a color map, the scan of the definitive cast and the intraoral scans were matched and compared in 3 dimensions. The Wilcoxon tests were used to compare the retention of the different bases (95% confidence interval, α=.05). RESULTS: Nineteen participants with a mean ±standard deviation age of 64.1 ±14.7 years completed the 4 study sessions. The retention of printed bases (PD: 16.08 ±15.28 N; LT: 14.98 ±14.72 N; RT: 11.28 ±9.57 N) and milled bases (PD:14.52 ±17.07 N; RT: 11.99 ±12.10 N; LT: 13.55 ±15.53 N) fabricated from conventional impressions presented significantly higher retentive forces than those printed (PD: 6.21 ±4.72 N; RT:5.12 ±2.78 N; LT: 4.45 ±2.77 N) and milled (PD: 6.58 ±4.92 N; RT: 4.65 ±2.63 N; LT: 5.02 ±3.58 N) from the intraoral scans (P<.05). The differences were significant in all directions of dislodgement, as well as after storage in artificial saliva for 2 weeks. Comparison of the 3D distances between the intraoral scan and the definitive cast revealed a mean deviation of 0.45 ±0.11 mm. CONCLUSIONS: Conventional impressions of the edentulous maxilla, including the clinical steps of border molding and posterior palatal seal compression, provide better retention than digital intraoral scans with both milled and 3D-printed denture bases.

Fit and retention of complete denture bases: Part I - Conventional versus CAD-CAM methods: A clinical controlled crossover study.

STATEMENT OF PROBLEM: Clinical evidence is sparse on whether dentures fabricated by computer-aided design and computer-aided manufacturing (CAD-CAM) methods afford superior fit and retention when compared with those fabricated conventionally. PURPOSE: The purpose of this clinical controlled crossover study was to evaluate the peak retention force and fit of CAD-CAM manufactured (3D-printed and milled) maxillary complete denture bases and conventional heat-polymerized bases (control). MATERIAL AND METHODS: Twenty participants with edentulous maxillary arches were recruited. Impressions were made with a border-molded custom tray, and the resulting definitive cast was scanned. The conventional base was manufactured on the definitive cast with a hook and a 45-degree platform with a central notch and 2 lateral notches. The scan of the definitive cast was used for the fabrication of a milled and a printed base. The platform and hook position on the conventional base were transferred digitally to the milled and printed bases. All bases were scanned. A traction dynamometer was orientated into the notches, and retention was evaluated in the post dam and tuberosity areas. Scans were imported into a comparison software program which matched scans to their corresponding reference and performed a 3-dimensional comparison. The Friedman and Wilcoxon tests were used to compare between groups (confidence interval: 95%, α=.05). RESULTS: Nineteen participants with a mean ±standard deviation age of 64.1 ±14.7 years completed all clinical sessions. No significant difference in peak retention was measured between milled (MB1), printed (PB1), and conventional (CB) bases in the post dam (CB: 12.44 ±9.62 N, PB1: 16.08 ±15.28 N, MB1: 14.52 ±17.07 N) and right tuberosity area (CB: 8.99 ±7.82 N, PB1: 11.28 ±9.57 N, MB1: 11.99 ±12.10 N). In the left tuberosity area, peak retention was lower for CB (10.03 ±8.39 N) than PB1 (14.98 ±14.72 N) and MB1 (13.55 ±15.53 N; P=.05). Compared with the definitive cast, the fit of the conventional base (0.18 ±0.01 mm) was closer than the printed (0.21 ±0.03 mm) and milled bases (0.21 ±0.02 mm) (P<.001). CONCLUSIONS: The CD bases manufactured by CAD-CAM techniques provided retention and fit similar to that of conventionally manufactured bases and can therefore be considered suitable techniques.

Clinical outcomes and costs of conventional and digital complete dentures in a university clinic: A retrospective study.

STATEMENT OF PROBLEM: Scientific data analyzing the clinical outcomes and costs of complete dentures fabricated by using conventional and computer-aided design and computer-aided manufacturing (CAD-CAM) processes are lacking. PURPOSE: The purpose of this retrospective study was to compare the treatment duration, financial costs, and postdelivery adjustments of CAD-CAM and conventional removable complete dentures. MATERIAL AND METHODS: Thirty-two edentulous participants (16 women, 16 men; age 35-85 years) who had received either CAD-CAM (n=16) or conventional (n=16) maxillary and mandibular removable complete dentures provided by prosthodontists with a minimum of 2 years of experience were evaluated. The CAD-CAM denture systems were either DDS-AV (AvaDent Digital Dental Solutions) (n=11) or DD-IV (Wieland Digital Denture) (n=5). The total treatment period (days) was recorded at 3 different time points (T0: preliminary alginate impression; T1: denture delivery; T2: last scheduled postdelivery adjustment). Adjustments during the follow-up (after T2) were noted and included the removal of areas of excessive pressure, relining, or repairs. The costs of the dental treatment and the laboratory fees were calculated. The Wilcoxon rank sum tests were used for statistical analysis (α=.05). RESULTS: No statistically significant difference regarding the treatment duration between digitally and conventionally fabricated removable complete dentures was found: T0-T1 (P=.889); T1-T2 (P=.675); T2- T3 (P=.978). No significant difference was found in the number adjustments for areas of excessive pressure, relines, or repairs (P=.757, P=1.000, P=1.000) during the period. Laboratory costs of CAD-CAM removable complete dentures were significantly lower than those of conventional removable complete dentures (P<.001), but clinical fees were similar between groups (P=.596), resulting in a reduction in the overall total costs for the CAD-CAM removable complete dentures (P=.011). Regarding the number of clinical visits, neither the group (conventional/CAD-CAM (P=.945)/DDS-AV/DD-IV [P=.848]) nor the interaction group (conventional/CAD-CAM and DDS-AV/DD-IV)/period (P=.084/P=.171) showed any significant differences. CONCLUSIONS: CAD-CAM removable complete dentures can be considered a viable alternative to conventional removable complete dentures regarding treatment duration, clinical and follow-up visits, adjustments, and maintenance requirements.

Oral care knowledge, attitude and practice: Caregivers' survey and observation.

OBJECTIVES: This study aims to assess caregivers' knowledge, perception and perceived barriers as well as their daily usual practice concerning oral care provision in a geriatric hospital. METHODS: A semi-structured questionnaire was developed and administered to caregivers in a geriatric ward. Furthermore, oral care delivery to dependent and independent patients was clinically observed. RESULTS: One hundred and fifty-two caregivers (60% nurses, 40% nursing aids) completed the survey (78% response rate). Clinical oral care was observed in 97 inpatients. Observations revealed that brushing was done in 94% of opportunities in independent patients but in only 55% of dependent patients. This corresponded to the frequency indicated in the questionnaire for independent elders (97%, n.s.), whereas it was significantly different for dependent elders (89%, P < .001). 95% of caregivers stated in the questionnaire never verifying self-administered oral care, whereas 12.3% were actually observed verifying intraorally its efficiency (P = .07 chi-squared test). 71% of the respondents stated storing the prostheses dry, and 8% stated that they reinserted it after cleaning. Caregivers' observation revealed that 35.1% of prostheses were reinserted in the mouth, indicating a significantly higher rate than in the questionnaire (P < .05). Respondents felt that their training to perform oral hygiene measures was suboptimal (VAS 48 ± 34.4). Patients verbally refusing oral care were stated as a barrier by 14% of respondents and were witnessed in 15.6% of observation opportunities (n.s). CONCLUSION: Various measures, such as hospital health policy, improved logistics or advanced hands-on training, might help to converge the clinical practice towards the theoretical knowledge.

Development of a European consensus from dentists, dental hygienists and physicians on a standard for oral health care in care-dependent older people: An e-Delphi study.

OBJECTIVES: This study aimed to obtain a consensus on oral health policy, access to dental care, oral hygiene measures and training levels. BACKGROUND: Poor oral health is widespread in care-dependent older people, but no consensus for a minimum standard of oral health care exists yet. METHODS: The e-Delphi approach was applied to a selected panel of interdisciplinary experts. Data analysis was based on three measurements: (a) ≥70% of experts' opinion fall into category "agree or strongly agree," (b) median score on the 5-point Likert scale ≥4, (c) interquartile range ≤1. RESULTS: A total of 31 experts from 17 European countries participated in this survey. Agreement was achieved for a compulsory dental examination when an elder is admitted to a long-term care (LTC) facility. Older people should brush their teeth twice/day and regularly clean interproximal spaces and oral mucosa. Dentures should be rinsed after meals and cleaned twice/day. The use of denture cleansing tablets was considered necessary. Dentures should be removed before sleeping and stored dry. A 5000 ppm fluoride toothpaste should be applied daily in elder with high caries risk. A short report on the oral health status of the elder should be included in the geriatric assessment. All experts concluded that the knowledge and the training in oral health care for caregivers and family members of care-dependent older people were imperative. CONCLUSIONS: Using the e-Delphi method, multidisciplinary healthcare professionals from different countries agreed on certain cardinal recommendations for a standard oral health care for care-dependent older people.

Mandibular two-implant overdentures with CAD-CAM milled bars with distal extensions or retentive anchors: A randomized controlled trial.

OBJECTIVE: This randomized controlled trial (RCT) aimed to demonstrate the non-inferiority of mandibular 2-implant overdentures (IODs) on a CAD-CAM milled bar with long distal extensions (MBDE) against IODs on retentive anchors (RA). METHODS: Forty edentulous participants rehabilitated with a maxillary conventional denture and a mandibular 2-IOD participated in this trial. They were randomized into two groups [Control group (CG): RA + gold matrices; Experimental group (EG): MBDE + gold clip]. The outcomes included implant survival rate (ISR), chewing efficiency [quantitative (VoH) and subjective (SA) assessments], peri-implant marginal bone levels (PI-MBL), maximum bite force (MBF), and patient-reported outcomes [oral health impact profile (OHIP-EDENT), and denture satisfaction index (DSI)]. Outcomes were recorded at baseline (BL), two weeks (T0 ), 6 months (T1 ), and at 1 year (T2 ) after the intervention. Intra- and inter-group analyses were performed using regression models with ⍺=0.05. RESULTS: 38 participants completed the T2 visit (CG: n = 19, age = 74.7 ± 7.8 years; EG: n = 19, age = 70.3 ± 10.7 years). At T2 , there was no implant loss in either of the groups (ISR = 100%). There were no significant differences between the groups for the PI-MBL changes (p = .754). Improvements occurred faster in the EG than in the CG, but over the observation time, there were no differences between the trial groups for VoH, MBF, OHIP-EDENT, and the DSI, except for SA being significantly better in the EG group (p = .022). CONCLUSIONS: The results of this RCT confirm that mandibular 2-IODs with a CAD-CAM milled bar with long distal extensions are not an inferior treatment to the conventional IODs on retentive anchors in the short term (1 year).

In vitro retention force changes during cyclic dislodging of three novel attachment systems for implant overdentures with different implant angulations.

OBJECTIVES: This in vitro study aimed to compare changes in retentive force due to cyclic dislodging of three novel un-splinted attachments. MATERIALS AND METHODS: Experimental models simulating a mandibular two-implant overdenture situation, with implants positioned with various interimplant discrepancies (0°, 20°, 40°, and 60°) were fabricated. Three attachment systems were tested, "N": a straight or 15°-angulated stud; "L": a sole straight stud; and "C": a straight or individually angulated stud. All models underwent wet testing and were subjected to 10,000 insertion-removal cycles in a universal testing machine. The mean retentive forces were calculated for cycles 10, 100, 1,000, 5,000, and 10,000. Multiple mixed-effects linear regression models were applied for statistical analyses (⍺ < 0.05). RESULTS: "N" demonstrated an increasing retention until 1,000 cycles, which subsequently diminished back to its initial retention at 10,000 cycles, showing no significant loss during the entire experiment. Statistical models demonstrated no effect of implant angulation on retention, except for 60° after 10,000 cycles (p < .05). "L" showed an early peak at 100 cycles and did not significantly lose retentive force before 5,000 cycles. Angulations of 40° or higher were shown to lead to lower retentive forces (0° vs. 40° cycle 5,000: p < .05; 0° vs. 60° cycle 100: p < .05, ≥cycle 1,000: p < .001). "C" showed stable retentive forces with no significant loss only at 10,000 cycles (all angles: p < .001) or 5,000 cycles (0° vs. 60°: p < .05). CONCLUSIONS: All systems showed retentive forces promising successful clinical use in implant overdentures, even in situations with extremely angulated implants. Specific abutments compensating interimplant angulation maintain retention longer in situations with high axe divergencies.

Implant overdentures retained by self-aligning stud-type attachments: A clinical report.

The functionality of a new overdenture attachment (LOCATOR R-Tx) was described for different clinical situations: a conventional mandibular implant overdenture (IOD) retained by 2 implants, a straightforward chairside maintenance procedure for replacing a worn LOCATOR (Legacy) attachment with the new LOCATOR R-Tx, and a complex clinical situation with nonideal implant positions with compromised parallelism. The LOCATOR R-Tx is an advance on the existing LOCATOR Legacy attachment and has an improved abutment head design with a more durable surface coating to prevent attachment wear and thereby reduce frequency of maintenance.

Effect of implant-supported mandibular overdentures versus reline on masticatory performance and salivary flow rates in very old adults-A randomized clinical trial.

PURPOSE: To compare the masticatory efficiency (ME), maximum voluntary bite force (MBF), masseter muscle thickness (MMT), and salivary flow rates (SFR) in completely edentulous dependent elders treated either with a conversion of their existing mandibular complete removable dental prostheses (CRDPs) into a two-implant overdenture (IOD) or a conventional reline of the CRDP. MATERIAL AND METHODS: Participants were randomly allocated into intervention (IG) and control (CG) groups. The IG received two implants in the mandibular canine regions, and their CRDPs were transformed into IODs. The CG received a conventional reline of their mandibular CRDPs. Outcomes were recorded at each recall visit (baseline, immediately, 3 months, 12 months after intervention, and subsequently on an annual basis). Statistical analyses used mixed linear regression models (level of significance: p < 0.05). RESULTS: The IG comprised 16 participants (age = 85.0 ± 6.2 years), while the CG comprised 16 (age = 84.8 ± 5.4 years), with a mean follow-up of 2.7 ± 2.2 years (range: 3 months-7 years). A significant increase of MBF in the IG was observed with an overall gain of 80 N (p < 0.001) compared with the reline group. There were no significant long-term changes in SFR, MMT, or ME within/between groups. CONCLUSION: Since dependent elders with mandibular IODs present a significant gain in MBF, but no relative increase in SFR, MMT, and ME, it seems that this increased capacity of MBF is not exploited by the elders during their habitual chewing.

Edentulous jaw impression techniques: An in vivo comparison of trueness.

STATEMENT OF PROBLEM: Simplified edentulous jaw impression techniques have gained popularity, while their validity has not yet been evaluated. PURPOSE: The purpose of this clinical study was to compare the trueness of maxillary edentulous jaw impressions made with irreversible hydrocolloid (ALG), polyvinyl siloxane (PVS), PVS modified with zinc oxide eugenol (ZOE) (PVSM), and an intraoral scanner (TRI) with a conventionally border-molded ZOE impression (control). MATERIAL AND METHODS: Twelve edentulous maxillary impressions were made with the impression techniques. The analog impressions were scanned using a laboratory scanner, imported into 3-dimensional comparison software, and superimposed against the corresponding control. Trueness was evaluated by calculating the effective deviation known as root mean square (RMS) for the entire surface (ES) and for specific regions of interest such as peripheral border, inner seal, midpalatal suture, ridge, and posterior palatal seal. The secondary outcomes for this study were the patients' perception of the impression techniques. Statistical analyses with the Wilcoxon tests were carried out (α=.05). RESULTS: For ES, significant differences were found when comparing ALG (1.21 ±0.35 mm) with PVS (0.75 ±0.17 mm; P=.008), PVSM (0.75 ±0.19 mm; P=.012), and TRI (0.70 ±0.18 mm; P=.006) but not among the other groups. Significant differences were found for peripheral border when comparing ALG (2.03 ±0.55 mm) with PVS (1.12 ±0.32 mm; P=.006), PVSM (1.05 ±0.29 mm; P=.003), and TRI (1.38 ±0.25 mm; P=.008), as well as TRI and PVSM (P=.028). Significant differences were also found for inner seal when comparing ALG (0.74 ±0.36 mm) with PVSM (0.52 ±0.13 mm; P=.041), as well as TRI (0.8 ±0.25 mm) versus PVS (0.56 ±0.14 mm; P=.005) and PVSM (P=.005). The difference at the ridge was significant when comparing PVS (0.18 ±0.07 mm) with PVSM (0.28 ±0.19 mm; P=.015) but not among the other groups. A significant difference was also found for posterior palatal seal when comparing PVS (0.55 ±0.41 mm) with PVSM (0.60 ±0.43 mm; P=.034). Patient perceptions showed significantly better satisfaction scores for ALG (1.83 ±2.03) and PVS (3.17 ±2.40) than for TRI (4.08 ±2.71), PVSM (4.58 ±2.35), and ZOE (6.83 ±1.75). CONCLUSIONS: Edentulous impressions made with PVS, PVSM, and TRI had similar deviations and may yield clinically acceptable results. Irreversible hydrocolloids are contraindicated for definitive impression making in completely edentulous jaws.

Decision making and management of root caries: A practice-based survey.

OBJECTIVES: With increasing life expectancy and improved preventive measures, teeth are retained longer, leading to a rise in prevalence of root caries lesions (RCL). However, little is known about how dentists manage this condition. The present survey aimed to evaluate the knowledge of Swiss dentists on decision making and management of RCL. METHOD: The survey evaluated dentists' knowledge, clinical routines, and demographics concerning RCL. Dentists were contacted via email and local newsletters, and 383 dentists from 25 (out of 26) cantons responded. Mann-Whitney U test, χ2 test, intraclass correlation coefficients, Spearman correlation and Chi Square were used. RESULTS: The dentists had a mean(SD) working experience of 22.5(12) years. Most dentists correctly classified an inactive (67%) and an active (81%)RCL. Although the inactive lesion did not call for restorative treatments, 61% of the dentist declared they would restore it. From the active lesion,83% would restore it. The invasive treatments leaned toward complete caries excavation with composite resin as preferred restorative material. There were significant correlations between material choice and expected success rates. Among the non-invasive options, oral hygiene instructions and (highly-)fluoridated toothpaste were favored. Most dentists declared having a recall system for such patients, with biannual follow-ups preferred. The dentists' place of education significantly influenced restorative decisions (p < 0.001), while participants' age (≥60years) impacted activity status (p = 0.048) and restorative decisions (p = 0.02). CONCLUSION: Material preferences for non-invasive or invasive management varied greatly and there were minimal differences in the management of inactive or an active RCL. Moreover, diagnosing active lesions appeared easier than diagnosing inactive ones. CLINICAL SIGNIFICANCE: Despite diverse material preferences for (non-)invasive treatments, a strong positive correlation existed between the chosen restorative material and its expected 2-year success rate. Moreover, diagnosing active lesions appeared easier than diagnosing inactive ones. The outcome emphasis the need to align guideline recommendations with their application in private dental practices.

Diagnosing and recording root caries: A survey among Swiss dentists.

OBJECTIVES: Despite the increase in the root caries prevalence, little is still known about how dentists manage this condition. The present study aimed to evaluate the knowledge of dentists on diagnosing and recording root caries lesions (RCL). METHODS: The survey consisted of three domains: (1) dentists' knowledge on diagnosing, recording and managing RCL; (2) information about their current general clinical routines; and (3) their demographics. The four Swiss Universities distributed the survey via e-mail lists for alumni or professionals participating in continuing education. The data was quality checked. Construct validity, internal reliability and intraclass correlation (ICC) were assessed. RESULTS: The survey was answered by 383 dentists from 25(out of 26) cantons [mean(SD) working experience: 22.5(12) years]. The majority replied that they see less than 5 patients with RCL per week, whereas 41 have at least 5 per week, and 40 % (157 dentists) do not distinguish RCL from coronal caries in their patients' medical records. When diagnosing active RCL, tactile sensation was the most predominant criterion (n = 380), whereas color (n = 224) and visual appearance (n = 129) of the lesion were less often selected. The most often chosen risk factors for RCL were poor oral hygiene and presence of biofilm.The responses were significantly influenced by the participants' place of education, their age and working area. CONCLUSION: The present survey highlights the huge diversity in diagnosing, recording and assessing risk factors of RCL. The benefits of an appropriate diagnosis, recording and management of risk factors of RCL should be highlighted in under- and postgraduate dental education. CLINICAL SIGNIFICANCE: A great diversity in diagnosing, recording and assessing risk factors of RCL was observed, which migh strongly impact how dentists manage RCL. The study emphasizes the necessity for intensive efforts to bridge the gap between guideline recommendations and their implementation in private dental practices.