Design of a randomized controlled double-blind crossover clinical trial to assess the effects of saliva substitutes on bovine enamel and dentin in situ

<p>Abstract</p> <p>Background</p> <p>Hyposalivation is caused by various syndromes, diabetes, drugs, inflammation, infection, or radiotherapy of the salivary glands. Patients with hyposalivation often show an increased caries incidence. Moreover, hyposalivation is frequently accompanied by oral discomfort and impaired oral functions, and saliva substitutes are widely used to alleviate oral symptoms. However, preference of saliva substitutes due to taste, handling, and relief of oral symptoms has been discussed controversially. Some of the marketed products have shown demineralizing effects on dental hard tissues <it>in vitro</it>. This demineralizing potential is attributed to the undersaturation with respect to calcium phosphates. Therefore, it is important to modify the mineralizing potential of saliva substitutes to prevent carious lesions. Thus, the aim of the present study was to evaluate the effects of a possible remineralizing saliva substitute (SN; modified Saliva natura) compared to a demineralizing one (G; Glandosane) on mineral parameters of sound bovine dentin and enamel as well as on artificially demineralized enamel specimens <it>in situ</it>. Moreover, oral well-being after use of each saliva substitute was recorded.</p> <p>Methods/Design</p> <p>Using a randomized, double-blind, crossover, phase II/III <it>in situ </it>trial, volunteers with hyposalivation utilize removable dentures containing bovine specimens during the experimental period. The volunteers are divided into two groups, and are required to apply both saliva substitutes for seven weeks each. After both test periods, differences in mineral loss and lesion depth between values before and after exposure are evaluated based on microradiographs. The oral well-being of the volunteers before and after therapy is determined using questionnaires. With respect to the microradiographic analysis, equal mineral losses and lesion depths of enamel and dentin specimens during treatment with SN and G, and no differences in patients' experienced oral comfort after SN compared to G usage are expected (H₀).</p> <p>Discussion</p> <p>Up to now, 14 patients have been included in the study, and no reasons for early termination of the trial have been identified. The design seems suitable for determining the effects of saliva substitutes on dental hard tissues <it>in situ</it>, and should provide detailed information on the oral well-being after use of different saliva substitutes in patients with hyposalivation.</p> <p>Trial registration</p> <p><b>ClinicalTrials.gov ID. </b><a href="http://www.clinicaltrials.gov/ct2/show/NCT01165970">NCT01165970</a></p

Conservative, Surgical, and Prosthetic Treatment of a Patient with a Periapical Lesion Associated with an Atypical Intraoral Sinus Tract

This report describes a clinical case with an atypical intraoral sinus tract formation from diagnosis and treatment to short-term outcome and definitive prosthetic rehabilitation. In detail, the patient underwent conservative nonsurgical root canal treatment followed by guided bone augmentation of the regions involved in periapical inflammation and sinus tract formation. The removal of the inflammatory source of the lesion as well as the affected tissue clearly led to a healing of the surrounding bone tissues. Subsequently, the tooth was reconstructed using a fibreglass post and a metal-ceramic crown; an implant was successfully placed in the previously inflamed bone region

Evaluation of cavitations in proximal caries lesions at various magnification levels in vitro

OBJECTIVES: The aim of this study was to evaluate the cavitation rate of proximal caries using different magnification aids in vitro. METHODS: Radiographs of 285 extracted teeth were taken and the proximal surfaces were graded to the criteria R0 (no radiolucency), R1 (radiolucency confined to the outer half of enamel), R2 (inner half of enamel) and R3 (outer half of dentin). Subsequently, the proximal surfaces were checked for the presence of cavitations with the naked eye (NE), and by using 4.3 x magnification eyeglasses (ME), a stereo microscope (SM, 10x), or a scanning electron microscope (SEM, up to 2000 x magnification). RESULTS: In surfaces with R3 caries, cavitations were visible in 56 of 59 cases with the naked eye. When using SEM, all surfaces revealed cavitations (100%). Regarding the surfaces with R2 lesion, 36 of 46 cases showed cavitations (NE); the corresponding values were 39/46 (ME), 41/46 (SM), and 46/46 (SEM); in the latter, in most cases deep defects could be observed. With regard to R1 lesions, 36/60 (NE), 43/60 (ME), 45/60 (SM), and 58/60 (SEM) cases revealed cavitations. A breakdown of radiographically sound surfaces (R0) was present in some 10% of the examined surfaces (24/261, NE; 33/261, SEM). CONCLUSIONS: Cavitations (defined as breakdown of the surface) are present in significantly more cases than previously reported. This might be an explanation why even small radiolucencies tend to progress, albeit slowly. Thus, close follow-ups should strongly be recommended when considering a preventive treatment regimen with small radiolucencies

Radiologic assessment of quality of root canal fillings and periapical status in an Austrian subpopulation – An observational study

<div><p>Background/Objective</p><p>Progress in endodontic techniques and methodological advances have altered root canal therapy over the last decades. These techniques and methods need periodical documentation. This observational study determined the current prevalence of endodontic treatments, and investigated the relationship of various factors with the periapical status in a Lower Austrian subpopulation.</p><p>Methodology</p><p>One thousand orthopantomograms of first-time university adult patients radiographed at an outpatient clinic were evaluated. For each tooth, the presence of periradicular pathosis and/or endodontic treatment was recorded, as was the quality of (post-)endodontic treatment (homogeneity and length of root canal fillings; preparation failures; posts/screws; apicoectomies; coronal restorations). Two evaluators, blinded to each other, scored all teeth. In cases of disagreement, they joined for a consensus score.</p><p>Results</p><p>In all, 22,586 teeth were counted. Of these, 2,907 teeth (12.9%) had periapical pathosis, while 2,504 teeth had undergone root canal treatment. Of the endodontically treated teeth, 52% showed no radiographic signs of apical periodontitis, while 44.9% had overt apical lesions, and 3,1% revealed widened periodontal ligament space. The majority of the root canal fillings was inhomogeneous (70.4%); 75.4% were rated too short, and 3.8% too long. The presence of apical pathosis was significantly correlated (odds ratio (OR) 2.556 [confidence interval (CI) 2.076–3.146]; <i>P</i><0.0001) with poor root canal fillings (length and homogeneity). Posts or screws positively affected periapical status (OR 1.853 [CI 1.219–2.819]; <i>P</i> = 0.004), but endodontically treated posterior teeth were infrequently restored (posts, 7.5%; screws, 2.7%). Best results were found for teeth with both appropriate endodontic treatment and adequate coronal restoration.</p><p>Conclusion</p><p>A high prevalence of periradicular radiolucencies was observed with root canal filled teeth, along with high numbers of unmet treatment needs. Periapical health was associated with adequate root canal obturation and high-grade postendodontic restorations, and quality regarding these latter aspects is considered mandatory to promote periapical health.</p></div

Kiviat diagram visualising the multivariate observations.

<p>Total amount of cases per combination is indicated by numbers (0–700). Inadequate length and inhomogeneous quality of root canal filling (RCF) strongly increased the proportion of apical pathosis (AP), and this was again tremendously affected by poor quality of coronal restoration (n = 2,007; note that total number of teeth represents unequivocal scores of the evaluators).</p

Distribution of patients and (root canal filled) teeth according to age and gender.

<p>Distribution of patients and (root canal filled) teeth according to age and gender.</p

Periradicular status in relation to various factors.

<p>Periradicular status in relation to various factors.</p

Distribution of apical pathosis (AP).

<p>Distribution is given by type of tooth, by jaw, and by gender for all root canal filled teeth (n = 2,373; note that total number of teeth represents unequivocal scores of the evaluators).</p

Periradicular status in relation to various combined factors ().

<p>Periradicular status in relation to various combined factors ().</p

The influence of saliva on the dissolution of calcium fluoride after application of different fluoride gels in vitro

OBJECTIVE: To determine the formation and dissolution of calcium fluoride on the enamel surface after application of two fluoride gel-saliva mixtures. METHOD AND MATERIALS: From each of 80 bovine incisors, two enamel specimens were prepared and subjected to two different treatment procedures. In group 1, 80 specimens were treated with a mixture of an amine fluoride gel (1.25% F-; pH 5.2; 5 minutes) and human saliva. In group 2, 80 enamel blocks were subjected to a mixture of sodium fluoride gel (1.25% F; pH 5.5; 5 minutes) and human saliva. Subsequent to fluoride treatment, 40 specimens from each group were stored in human saliva and sterile water, respectively. Ten specimens were removed after each of 1 hour, 24 hours, 2 days, and 5 days and analyzed according to potassium hydroxide-soluble fluoride. RESULTS: Application of amine fluoride gel resulted in a higher amount of potassium hydroxide-soluble fluoride than did sodium fluoride gel 1 hour after application. Saliva exerted an inhibitory effect according to the dissolution rate of calcium fluoride. However, after 5 days, more than 90% of the precipitated calcium fluoride was dissolved in the amine fluoride group, and almost all potassium hydroxide-soluble fluoride was lost in the sodium fluoride group. Calcium fluoride apparently dissolves rapidly, even at almost neutral pH. CONCLUSION: Considering the limitations of an in vitro study, it is concluded that highly concentrated fluoride gels should be applied at an adequate frequency to reestablish a calcium fluoride-like layer