Purpose: Diminished salivary flow, or dry mouth impacts the oral health of many older adults, dentate and edentulous. As a result typical oral conditions can prove more challenging to both the patient's comfort and home care and the treatment selected by the clinician. This paper will review issues of dry mouth from a clinical and symptomatic perspective and will include the condition's causes, treatment and prevention.
Study selection: We performed a review of PubMed using the words: older adults, dry mouth, xerostomia, radiation-induced xerostomia, and salivary gland hypofunction. We selected 90 articles with a clinical application perspective.
Results: When it comes to treatment of dry mouth conditions, either objective or subjective, there are no easy answers as to the best course of action for a specific individual. While most of the cited studies have examined the most difficult cases of dry mouth (e.g. Sjögren's syndrome, and that seen during and post head and neck cancer treatments), there are many older adults who demonstrate dry mouth from the use of multiple medications. This paper presents a summary of the etiology, diagnosis, prevention, and pharmacological and non-pharmacological treatment of dry mouth (salivary hypofunction and xerostomia in older adults).
Conclusions: It is important to understand the causes of dry mouth and to educate our patients. Starting a prevention program as early as possible considering the most practical, cost effective and efficient treatments with the best risk-benefit ratio will help to diminish dry mouth symptoms and sequelae.

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Purpose: Titanium is a primary metallic biomaterial used in load-bearing orthopedic or dental implants because of its favorable mechanical properties and osseointegration capability. This article reviews the current status of surface optimization techniques for titanium implants, whether such concepts are in the form of sufficiently evidence-based, and highlights the related experimental tools.
Study selection: A strong emphasis was placed on the enhanced biological responses to titanium implants by modifying the surface finishing process. On this basis, a clear partition of surface chemistry and topography was critical.
Results: The intrinsic host tissue response to titanium implants is facilitated by the chemistry or topography of a passive oxide film, although the extent to which the surface characteristics enable rapid osseointegration is still uncertain.
Conclusion: Besides the fundamental requirements, such as the promotion of osteogenic differentiation, the titanium implant surface should accelerate wound-healing phenomena prior to bone ingrowth toward the surface. Moreover, because initial bacterial attachment to the implant surface is unavoidable, infection control by surface modification is also an important determinant in reducing surgical failure. A desirable surface–biological relationship often needs to be characterized at the nanoscale by means of advanced technologies.

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Purpose: Prosthodontic treatment has a positive effect on oral health-related quality of life (OHRQoL); however, there is a paucity of studies assessing the impact of OHRQoL based on where in the mouth ("location") the treatment is performed. This exploratory study investigated the association of the location (anterior, posterior region) of prosthodontic treatment with magnitude and nature of OHRQoL changes.
Methods: In this non-randomized prospective clinical study, 190 adult patients (17–83 years) were recruited at baseline and 104 were available for the follow-up analyses. Of those, 50 patients received treatment only in the posterior segment and 54 patients in both anterior and posterior regions. Treatment included conventional fixed partial prostheses, removable prostheses or a combination of both. OHRQoL was assessed with the German language version of the 49-item Oral Health Impact Profile (OHIP) at baseline and the questionnaire was repeated 4–6 weeks post-treatment. Magnitude and effect size of changes in summary and sub-scale scores were calculated and data analyzed.
Results: Patients experienced a substantially impaired OHRQoL (mean OHIP score: 32.3 points) at baseline and an improvement in OHRQoL of 6.8 OHIP points following treatment. This study showed a greater improvement in OHRQoL in patients treated in both regions compared to those treated in the posterior region alone, especially in the function and aesthetic domains.
Conclusions: This explorative study suggests that OHRQoL improvement is affected by where prosthodontic treatment is performed in the mouth. Greater understanding of qualitative aspects of reconstructive therapies is needed for improved treatment planning and patient consent.

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Purpose: The aim of this study was to investigate the susceptibility of Candida albicans and Candida glabrata biofilm development, in their intermediate and maturation stages, to the influence of silver nanoparticles (SN).
Methods: SN (5 nm) suspensions were synthesized via reduction of silver nitrate by a solution of sodium citrate. These suspensions were used to treat Candida biofilms for five hours, grown on acrylic surfaces for 24-h (intermediate stage) and 48-h (maturation stage), and their efficacy was determined by total biomass (using crystal violet staining) and colony forming units (CFUs) quantification.
Results: SN promoted significant reductions (p < 0.05) in the total biomass and number of CFUs of Candida biofilms, ranging from 23% to 51.5% and 0.63 to 1.59-log₁₀, respectively. Moreover, there were no significant differences in the total biofilm biomass (p > 0.05), when the different stages of biofilm development (24 or 48 h) were exposed to SN. Comparing the number of CFUs between 24- and 48-h biofilms treated with SN, a significant difference (p < 0.05) was found only for the C. albicans 324LA/94 strain.
Conclusions: In general, the intermediate and maturation stages of biofilm development do not interfere in the susceptibility of C. albicans and C. glabrata biofilms to SN. These findings are fundamental for the deployment of new therapies aimed at preventing denture stomatitis.

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Purpose: Laminated alginate impression for edentulous is simple and time efficient compared to border molding technique. The purpose of this study was to examine clinical applicability of the laminated alginate impression, by measuring the effects of different Water/Powder (W/P) and mixing methods, and different bonding methods in the secondary impression of alginate impression.
Methods: Three W/P: manufacturer-designated mixing water amount (standard), 1.5-fold (1.5×) and 1.75-fold (1.75×) water amount were mixed by manual and automatic mixing methods. Initial and complete setting time, permanent and elastic deformation, and consistency of the secondary impression were investigated (n=10). Additionally, tensile bond strength between the primary and secondary impression were measured in the following surface treatment; air blow only (A), surface baking (B), and alginate impression material bonding agent (ALGI-BOND: AB) (n=12).
Results: Initial setting times significantly shortened with automatic mixing for all W/P (p < 0.05). The permanent deformation decreased and elastic deformation increased as high W/P, regardless of the mixing method. Elastic deformation significantly reduced in 1.5× and 1.75× with automatic mixing (p < 0.05). All of these properties resulted within JIS standards. For all W/P, AB showed a significantly high bonding strength as compared to A and B (p < 0.01).
Conclusions: The increase of mixing water, 1.5× and 1.75×, resulted within JIS standards in setting time, suggesting its applicability in clinical setting. The use of automatic mixing device decreased elastic strain and shortening of the curing time. For the secondary impression application of adhesives on the primary impression gives secure adhesion.

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Purpose: Zirconia/alumina nanocomposite stabilized with cerium oxide (Ce-TZP/A) shows significantly higher mechanical strength than yttrium-oxide-partially-stabilized zirconia (Y-TZP) and allows post-sintered machining that does not require any subsequent treatment. The aim of this prospective study was to assess the clinical performance of veneered Ce-TZP/A frameworks for fixed dental prostheses.
Methods: Fifteen patients with 22 Ce-TZP/A fixed prostheses were included in this study. The fixed dental prostheses were cemented with resin cement (baseline) and were evaluated at baseline and at 1, 6, 12, 24 and 36 months after cementation. Clinical events, including fracture and loss of retention, secondary caries, and marginal integrity, were recorded. The biologic outcome was judged by comparing the pre-treatment and post-treatment bleeding on probing (BOP), and probing pocket depth (PPD) of the abutment teeth. Radiographic examination was also performed at 12, 24 and 36 months.
Results: The mean observation period was 35.9 ± 5.5 months. During this period, one abutment tooth was extracted due to root fracture and the survival rate was 95.2%. No significant change in BOP, PPD, and radiographic image was found during the 36-month follow-up period.
Conclusion: Within the limitations of this study, Ce-TZP/A was found to provide sufficient stability as a framework material in all regions. Special attention, however, must be paid to designing framework that provides sufficient support for the veneer. Furthermore, studies with longer observation periods and more patients are needed.

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Purpose: Nanopolymorphic crystalline Hydroxyapatite (HA)-coated implants were different in surface property from conventional HA-coated implants subjected to previous clinical studies. The purposes of the present study were to retrospectively evaluate 10-years clinical outcome of the HA-coated implants (HA implants) with a comparison to the same system implants with anodic oxidized titanium surface (Ti implants).
Methods: Cumulative survival rate (CSR) of HA or Ti implants placed in 183 patients (55 ± 12.4 years old) over two decades was calculated with life table analysis. Differences in CSR at each interval year, sex, age, frequency of number of implant placement according to implant location and diameter were compared between both types of implants.
Results: Total 455 HA implants and 255 Ti implants were included. CSR at upper molar site was consistently higher in HA implants than Ti implants until 8 years after placement. The values after 10 years was 89.9% or 77.7% in HA or Ti implants, respectively. There were no significant differences in overall CSR at any interval year. HA implants were more distributed at upper molar site but less at lower molar site than Ti implants. Diameter of HA implants tended to be wider than Ti implants.
Conclusions: Under limitation of this retrospective study, the nanopolymorphic crystalline HA-coated implants were more survived at upper molar site than anodic oxidized implants until 8 years after placement. This clinical outcome might attribute to differences in topographical and physicochemical characteristics between both types of implants.

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Purpose: The purpose of this study was to evaluate the distribution of bubbles, degree of mixing, flowability and mechanical strength of powder–liquid reline material by manually and with a rotation–revolution (planetary) mixer, and to determine the usefulness of a rotation–revolution mixer for this application.
Methods: Powder–liquid reline material (Mild Rebaron, GC, Tokyo, Japan) was mixed with a powder to liquid ratio of 1:0.62 according to the manufacturer's instruction. Two methods were used to mix it: mixed by manually ("manual-mixing") and automatically with a rotation–revolution mixer (Super Rakuneru Fine, GC, Tokyo, Japan; "automatic-mixing"). Disc-shaped specimens, 30 mm in diameter and 1.0 mm in thickness, were used to observe the distribution of bubbles in at 10× magnifications. Flowability tests were carried out according to the JIS T6521 for denture base hard reline materials. A three point bending test was carried out by a universal testing machine. Elastic modulus and flexural stress at the proportional limit were calculated.
Results: A median of 4 bubbles and inhomogeneous were observed in manual-mixed specimens. However, no bubbles and homogeneous were observed in automatic-mixed specimens. Flowability was within the JIS range in all mixing conditions and did not differ significantly across conditions. The elastic modulus was the same for manual-mixed and automatic-mixed specimens. On the other hand, the flexural stress at the proportional limit differed significantly between manual-mixed and automatic-mixed specimens.
Conclusion: The results confirm that rotation–revolution mixer is useful for mixing powder–liquid reline material. Automatic-mixing may be recommended for clinical practice.

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