Micromorphology of sialoliths in submandibular salivary gland: a scanning electron microscope and X-ray diffraction analysis.

PURPOSE: Sialoliths are common in the submandibular gland and its duct system. The exact cause of formation of a sialolith is still a matter of debate. The aim of this study was to analyze 6 sialoliths ultrastructurally to determine their development mechanism in the submandibular salivary glands. MATERIALS AND METHODS: Six sialoliths retrieved from the hilus and duct of the submandibular salivary glands of 6 patients with sialadenitis were analyzed ultrastructurally by scanning electron microscope and x-ray diffractometer. RESULTS: Scanning electron microscope revealed mainly irregular, partly rudely hexagonal, needle-like and plate-shaped crystals. The cross-section from the surface to the inner part of the sialoliths showed no organic material. X-ray diffraction showed that the sialoliths were composed of hydroxyapatite crystals. Energy dispersive x-ray microanalysis showed that all of the samples contained high levels of Ca and P, and small amounts of Mg, Na, Cl, Si, Fe, and K. CONCLUSION: The main structures of the submandibular sialoliths were found to be hydroxyapatite crystals. No organic cores were observed in the central parts of the sialoliths. In accordance with these preliminary results, sialoliths in the submandibular salivary glands may arise secondary to sialadenitis, but not via a luminal organic nidus.     

含锌碳磷灰石的溶胶凝胶法制备及性能表征

目的通过溶胶凝胶法制备含锌的碳磷灰石（Zn- CHA）涂层材料,并探讨锌离子取代反应对羟磷灰石物理化学性质的影响。方法实验制备了锌离子取代量和钙磷比不相同的两组样本,其中钙足量组样本的钙磷比为1.67,锌离子取代4%的钙离子;钙不足量组的钙磷比小于1.67,锌离子取代8%的钙离子。采用X射线衍射仪（XRD）、傅立叶变换红外光谱仪（FTIR）对样本的物相结构和化学组成进行分析研究,并采用扫描电镜观察样本的表面形貌。此外,还采用原子吸收分光光度计（AAS）对样本的溶解特性与锌离子的关系进行研究。结果X射线衍射分析表明样本中含有羟磷灰石相,傅立叶变换红外光谱分析结果表明样本为碳磷灰石,溶解实验表明钙不足量组和钙足量组样本中分别存在锌离子整合到羟磷灰石晶格内和吸附在羟磷灰石晶体表面两种情况。结论研究表明含锌的碳磷灰石能够通过简单的溶胶凝胶法制备获得。     

Comparative study on mineralization-related intraoral parameters in periodontitis-affected and periodontitis-free adults

Abstract – The parameters related to an intraoral mineralization tendency in periodontitis-affected (P+) and periodontitis-free (P-) study subjects (16 adults, 46–74 yr, matched for sex and age) were compared. For this purpose the calcium (Ca) and phosphate (P) concentration of both plaque and saliva, resting pH and the acidogenic response of interdental plaque, plaque wet weight, salivary flow rate, buffering capacity and sucrase activity, interdental and salivary S. mutans levels as well as salivary lactobacilli and yeast levels were estimated. Plaque Ca (μg/mg protein, P <0.025) and P (μg/mg protein, P <0.05), saliva Ca (μg/ml, P <0.005) and the saliva Ca:P ratio ( P <0.005) were higher in the P+ than in the P- group. The resting pH values were higher ( P <0.025) and the acidogenic response of the interdental plaque was lower ( P <0.025) in the P+ group than in the P- group. The P+ group had lower S. mutans levels in saliva and interdental plaque. No differences were found in the wet weight of plaque and in the flow rate, buffering capacity or sucrase activity of saliva between the groups. The findings of the mineralization-related parameters in the two "extreme" groups of periodontal status suggest a higher intraoral mineralization tendency in periodontitis-affected persons than in periodontitis-free subjects. Ca and P accumulation of supragingival plaque seem to be connected with low acidogenicity of plaque and high salivary Ca concentration.     

Multiple, large sialoliths of the submandibular gland duct: a case report

This paper reviews the major clinical and radiographic features of sialoliths and illustrates these with an unusual case of multiple sialoliths within the submandibular gland duct. The differential diagnosis of other calcific structures both within and outside the salivary gland that may mimic a sialolith is also presented.     

Hydroxyapatite coating on a titanium metal substrate by a discharging method in modified artificial body fluid

PURPOSE: The aim of this study was to evaluate the formation of a hydroxyapatite coating on titanium plate by discharging in typical and modified artificial body fluids. MATERIALS AND METHODS: Japanese Industrial Standard Grade 2 titanium plates were used as specimens. Discharging was performed on the specimens in each solution, and the surface topography of each coating was observed with a scanning electron microscope. The Ca/P atomic ratio and surface characterization of each coating were evaluated by x-ray photoelectron spectroscopy, and crystal phases of each coating were analyzed by Fourier transform infrared spectroscopy and x-ray diffraction. RESULTS: Tricalcium phosphate formed on the titanium surface in a 1.5 Ca/P solution with high ion concentrations of calcium (2.5 mmol/L) and phosphorous (1.67 mmol/L). Crystalline HA was formed on the titanium surface in a 1.5 Ca/P solution (Hanks' balanced salt solution without organic molecules) with low ion concentrations of calcium (1.26 mmol/L) and phosphorus (0.83 mmol/L). DISCUSSION: A solution containing organic pH buffer was insufficient to form stable coatings on the titanium surface. Coating properties strongly depended on the Ca/P chemical ratio of the applied solution. A Ca/P ratio of 1.5 was appropriate for preparing a calcium phosphate coating on a titanium surface, whereas a Ca/P ratio of 2.5 was excessively high. CONCLUSION: These findings suggest that Hanks' balanced salt solution without organic molecules is the most suitable solution for forming crystalline hydroxyapatite coatings on titanium surfaces by the discharging method.     

Unusual asymptomatic giant sialolith of the submandibular gland: a clinical report

This report presents an unusual case of asymptomatic sialolith of the submandibular gland. A 61-year-old man was referred to our department for multiple extractions. An ortopantomographic exam revealed the existence of a large radiopacity in the right premolar mandibular region. The patient was completely asymptomatic and no episodes of pain and swelling had occurred in the previous years. Ultrasonography and clinical examination confirmed the diagnosis of sialolithiasis of the submandibular duct. The calculus was removed trans-orally in local anaesthesia. The sialolith measured 22 mm and it was mainly constituted by phosphate, calcium and smaller amounts of magnesium. The bacteriological exam revealed the presence of Streptococcus Mitis, Streptococcus Salivarius and non-pathogenic Neisserie. Postoperative course was uneventful. Even a sialolith of significant dimensions may not be symptomatic. Nevertheless, the likelihood of future complications may constitute an indication for surgical removal of abnormal asymptomatic sialoliths.     

Behaviour of different bioactive glasses incorporated in polydimethylsiloxane endodontic sealer

ObjectivesThe aim of this study was to analyze the behavior of different bioactive glass fillers (BAGs) embedded in a polydimethylsiloxane matrix of an endodontic sealer.MethodsThree different endodontic sealers were fabricated using S53P4, 45S5 and 18?06 glass fillers. Endodontic sealer Guttaflow Bioseal consisting of polydimethylsiloxane (PDMS) matrix was used as base of the experimental sealers. Behaviors of different glass fillers leaching from polymer matrix was studied in vitro for 14 days by measuring static ion dissolution profiles of Si, Na, Ca and P -ions. In addition, pH of the simulated bodyfluid (SBF) was monitored during the 14 days and all the sealer samples was examined with SEM/EDX analysis on the surface. Identical but non-glass filler containing polydimethylsiloxane-based sealer was used as a control material.ResultsBy the time point of 24 h sealer with 45S5 had released twice as much of Si-ions compared to sealer with S53P4. No statistical differences of Na, Ca and P -ions dissolution were observed in the first 168 h for any groups whereas concentrations of Ca and P -ions decreased with 45S5 significantly after 336 h. Highest pH was measured for sealers with glass filler 45S5 and S53P4 (7.64–7.65). Visible mineral precipitation was observed only on sealer surfaces after 336 h’ time period with groups of 45S5 and S53P4. However, presence of calcium and phosphorus oxides was confirmed only with 45S5.SignificanceBioactive glass type 45S5 outperforms S53P4 and 18?06 by acting more dynamically in vitro set-up     

Periodontally diseased vs. normal roots as evaluated by scanning electron microscopy and electron probe analysis

A scanning electron microscope and electron probe study was carried out to compare root structure from deep within periodontal pockets with roots exhibiting no periodontal disease. To eliminate the possibility of extraneous ion introduction or deletion, no attempt was made to subject the roots to fixation, embedding, or dehydration prior to sectioning and viewing in the electron microscope. Mineral content and concentration were determined with an electron probe on two specimens per tooth. On one specimen, only the external cemental surface was analyzed. On an adjacent cross section, readings were taken from the surface and at incremental depths into the root. A nonparametric statistical analysis compared diseased with nondiseased roots. The following conclusions can be drawn from the study: (1) Consistent and repeatable qualitative electron probe analyses can be performed on human teeth with minimal specimen preparation. This gives a more accurate assessment, since the integrity of the crystalline structure is not disrupted. (2) Minerals consistently found were P, Ca, Cu, Zn, Mg and Na. They were in similar concentrations throughout the area analyzed. (3) Mg and Cu showed higher values in the nondiseased teeth. (4) There were no differences in concentrations for Ca, P, Zn, and Na between roots exposed to a periodontal pocket and nondiseased roots.     

Aspiration and characterization of predentin fluid in developing rat teeth by means of a micropuncture and micro-analytical technique

A fluid phase was aspirated in vivo and in vitro from predentin or pulp of developing rat teeth by means of a micropuncture technique. Pooled aspirates (approx. 2 nL) were analyzed for P, Na, K, Ca, Mg, and S by electron probe microtechniques (Lechene and Warner, 1979). Compared with pulp fluid, currently and previously studied cartilage fluids, as well as serum, predentin fluid showed elevated K, depressed Na, Cl, and Ca, as well as increased P. Statistical analysis was possible for only a few groups of comparisons among the elemental profiles. Ultrastructural examination of the aspiration site and of the aspirates showed no evidence of contamination with cell organelles or other formed elements. The micropuncture technique used was a critically precise and laborious procedure; possible contamination with intracellular fluid could not be avoided. The consistently low Mg concentration found in the aspirates, however, supports our view that the samples were primarily extracellular.     

Effects of a calcium phosphate coating on the osseointegration of endosseous implants in a rabbit model

Objectives: The aim of the present study was to evaluate a Ca–P coated implant surface in a rabbit model. The Ca–P surface (test) was compared to the titanium porous oxide surface (control) in terms of bone‐to‐implant contact (BIC) and removal torque value. Materials and methods: Two hundred and sixteen dental implants were inserted in the tibia and in the femur of 36 rabbits. One hundred and eight were represented by Ca–P oxidized surface implant and other 108 were titanium porous oxide surface modified implants. Each rabbit received six implants. Animals were sacrificed after 2, 4 and 9 weeks of healing. Each group included 12 rabbits. The femoral implant and the proximal implant of the tibia of each animal were subjected to the histologic analysis and the distal implants of the tibia underwent removal torque test (RTQ). Results: Histological analysis in terms of BIC and RTQ did not revealed any significant difference between the Ca–P oxidized surface and the oxidized surface at 2 and 4 weeks. At 9 weeks, the oxidized surface demonstrated better results in terms of RTQ in the tibia. Conclusion: In conclusion, findings from the present study suggested that the Ca–P coating had no beneficial effect in improving bonding strength at the bone–implant interface either at 2, 4 and 9 weeks. To cite this article:
Fontana F, Rocchietta I, Addis A, Schupbach P, Zanotti G, Simion M. Effects of a calcium phosphate coating on the osseointegration of endosseous implants in a rabbit model
Clin. Oral Impl. Res. 22 , 2011; 760–766
doi: 10.1111/j.1600‐0501.2010.02056.x     

Dissolution and precipitation reactions in human tooth enamel under weak acid conditions

Slices of enamel were demineralized in weak acid solutions at pH 5. The solutions were analysed for Ca, P, Na and Mg. A substantial increase of the Ca/P ratio in the solution after about 6 h of demineralization was ascribed to brushite formation. The ratios of liberated Ca/Na, P/Na, Ca/Mg and P/Mg were always lower than the correspondent ratios in sound enamel. It was concluded that precipitation of brushite, and a preferential dissolution of Na and Mg compounds from the enamel both play a role in the dissolution-precipitation reactions in dental enamel during acid attack.     

Saliva flow rate, amylase activity, and protein and electrolyte concentrations in saliva after acute alcohol consumption

OBJECTIVE: The aim of our study was to evaluate the effects of acute alcohol consumption on saliva secretion rate and selected salivary parameters in healthy nonalcoholic volunteers. STUDY DESIGN: Twenty-four volunteers (37.7 +/- 9.6 years, mean +/- SD) consumed 0.6 g or 0.7 g alcohol/kg of body weight (for women and men, respectively) in a soft drink. Saliva samples were collected, first (S0) before any alcohol was consumed, 45 minutes after consumption (S1) and, finally, 60 minutes after S1 (S2). Flow rates of both resting whole saliva and paraffin-stimulated (SWS) whole saliva were assessed. SWS was assessed for amylase, total protein, inorganic phosphate (PO4(3-)), sodium (Na+), potassium (K+), and calcium (Ca2+) content. RESULTS: SWS, but not resting whole saliva (in milliliters/minute), decreased significantly after consumption of alcohol. Amylase activity (P =.010) and the concentrations of Na+ (P =.000) and Ca2+ (P =.002) decreased significantly between S0 and S1. When SWS was analyzed for output, the total protein concentration (S0 to S1, P =.000; S0 to S2, P =.033) and amylase activity (S0 to S1, P =.000) decreased significantly. Further, the output of all the studied electrolytes decreased significantly as blood alcohol concentration increased. CONCLUSIONS: We conclude that acute alcohol consumption causes a decrease in SWS flow rate. The decrease in flow rate also results in impaired output of total protein and amylase, as well as in a decrease in the output of electrolytes.     

钛种植体载银抗菌羟基磷灰石涂层的制备及结构特征

目的：探讨真空等离子喷涂法制备钛种植体载银抗菌羟基磷灰石涂层材料的方法，并对其表面形貌、化学成分及晶相进行分析。方法：采用真空等离子喷涂技术，在钛基材表面制备含磷酸锆载银抗菌剂的抗菌羟基磷灰石涂层材料。按抗菌剂重量百分比将样本分为A组（0％）、B组（2％）、C组（5％）和D组（10％）。扫描电子显微镜下观察并比较各组涂层的形貌。用电子探针分析其表面化学成分。并以X射线衍射仪测定各组涂层的晶相组成。结果：4组涂层材料镜下表面形貌相似，均为球状颗粒中夹杂“饼状”结构及气孔；A、B、C组晶相主要呈现羟基磷灰石主要成分Ca10（OH）2（PO4）6的特征峰，且随抗菌剂含量上升，峰值降低。D组除主要呈现Ca10（OH）2（PO4）6的特征峰外，还出现CaZr（PO4）2、Na6CaP2O9等新相。电子探针检测法在A、B组涂层中未检测到Ag，C组和D组中测得Ag含量相似。结论：利用真空等离子喷涂技术，可制备含抗菌成分Ag的钛表面羟基磷灰石涂层材料，抗菌剂添加比例为5％较为适宜。     

Intraoral removal of a giant submandibular sialolith obstructing Wharton's duct: a case report

Sialolithiasis is one of the most common pathologies of the submandibular gland; sialoliths account for about 80 percent of all salivary duct calculi. This report presents the unusual case of a large asymptomatic sialolith of the submandibular duct, initially diagnosed as a possible tumor. The giant sialolith was removed via an intraoral approach under local anesthesia. The etiology, pathogenesis, and management of such giant sialoliths are discussed.     

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目的    研究改良热分解法制备的钛金属表面钛酸钙复合涂层材料的特性。方法   应用改良热分解法在钛金属表面制备钛酸钙复合涂层材料,该涂层由含有无定形碳的钛酸钙（CaTiO3-αC）与羟基磷灰石（HA）组成。实验中通过控制钙磷比（Ca／P）、钙钛比（Ca／Ti）、烧结温度和烧结速率,使CaTiO3颗粒的晶体结构中含有摩尔分数为4%的无定形碳。结果    通过对HA中碳的检测,证实了存在碳酸磷灰石的结构。钛表面的黏附-分离实验显示,CaTiO3-αC／HA涂层的黏附强度是单纯HA涂层的2.5倍。结论    改良热分解法制备的CaTiO3-αC层（0.6 μm厚）和含有碳酸磷灰石的HA层（2.4 μm厚）组成的双层生物活性材料能够作为钛表面理想的涂层材料。     

应用IBAD方法制备纯钛表面多孔TCP／HA涂层材料的微观分析

目的:为了改善钛种植体的生物相容性,对纯钛表面沉积多孔磷酸三钙/羟基磷灰石(Tricalciumphosphate/hydroxyapatite,TCP/HA)复合涂层材料的表面结构和化学成分进行分析,并与沉积羟基磷灰石(Hydroxyapatite,HA)的钛表面进行对比。方法:用离子束辅助沉积方法(Ionbeamassisteddeposition,IBAD)在纯钛表面沉积HA和TCP/HA涂层材料,通过扫描电镜(Scanningelectronmicroscope,SEM)、原子力显微镜(Atomicforcemicroscopy,AFM)、X射线能谱分析(EnergydispersiveX-rayanalysis,EDX)以及X射线衍射(X-raydiffraction,XRD)技术,检测两种涂层材料表面的微观形态和化学成分,并进行比较。结果:SEM和AFM显示TCP/HA涂层材料表面存在多孔结构,表面化学成分分析显示TCP/HA涂层的钙磷比低于HA,XRD证实TCP/HA涂层内同时存在TCP和HA两种化合物。结论:用IBAD方法在纯钛表面成功地沉积了具有多孔结构的TCP/HA复合涂层材料,该涂层材料和基体材料的结合牢固,改善了基体材料的生物相容性,是一种有应用前景的种植体表面涂层材料。     

Caries predicting factors in adult patients participating in a dental health program

The main purpose was to study various factors with respect to predicting dental caries. From a population of 442 employees at a shipyard, 68 patients with an average age of 56 yr were selected for the present investigation. They were examined once a year during a 2-yr period with respect to: 1) number of new caries lesions, and 2) a series of caries related factors, i.e., DMFS, oral hygiene status, dietary habits, numbers of Streptococcus mutans and lactobacilli in saliva, and secretion rate and buffer effect of saliva. The median values of all studied variables as found at the baseline examination were more favorable in the caries inactive (n = 30) than in the caries active group (n = 38), but only DMFS (P less than 0.001), dietary score (P less than 0.05), and number of S. mutans in saliva (P less than 0.05) differed significantly between the two groups. Number of S. mutans showed the highest sensitivity value, followed by dietary score. The main conclusion from this study is, however, that in spite of a relationship between caries activity and unfavorable values, especially for DMFS, dietary score, and number of S. mutans in saliva, it would have been difficult to predict the caries active patients on an individual level.     

Dislodgement of a submandibular gland sialolith during nasal intubation. A case report

A case of dislodgement of a submandibular sialolith into the oropharynx during nasal intubation is presented. The deleterious effect of the patient aspirating the stone into the lungs was averted by the taking of a lateral skull radiograph and localization and removal of the sialolith.