Salivary micelles: identification of complexes containing MG2, sIgA, lactoferrin, amylase, glycosylated proline-rich protein and lysozyme

Micelles represent macromolecular structures in saliva and the aim of this study was to identify salivary proteins that occur in these globular particles. Micelles were isolated from whole saliva (WS) collected from three individuals and analysed in different experiments. Samples were subjected to polyacrylamide gel electrophoreses, hydrolysed to determine their amino acid composition and total protein concentration, examined by scanning electron microscopy and examined on Western blots probed with a panel of antibodies directed against salivary proteins. On Coomassie Brilliant Blue stained gels, the banding pattern of whole saliva and micelles was similar but the intensity of bands was quite different. Amino acid analysis confirmed that the amino acid composition of micelles was distinct from that of whole saliva. Scanning electron microscopy showed that micelles exhibit a complex pattern consisting of individual particles or clusters of particles with different sizes and shapes. Micelles contain proteins with high (MG2 and secretory IgA), intermediate (lactoferrin, amylase and glycosylated proline-rich protein (PRP)) and low (lysozyme) molecular weight that were immuno-detected on blots probed with specific antibodies. Micelles represent particulate multicomponent structures in whole saliva that contain a subset of salivary proteins known to be important components of the innate immune system and are likely to play an important role in the maintenance of homeostasis in the oral environment.     

Dental maturity in children of short stature, with or without growth hormone deficiency

The aim of this investigation was to study dental maturity in healthy prepubertal children of short stature (height < −2 SD), with or without growth hormone (GH) deficiency, compared to healthy controls. The GH-deficient group (GH level < 10.0 μg/l) included 29 children (11 female. 18 male) with a mean age of 10.2 ± 2.2 years. The GH non-deficient group consisted of 17 children (5 female. 12 male) with a mean age of 8.5 ± 2.1 years. All the children were evaluated for serum concentrations of IGF-1, alkaline phosphatase (ALP), triiodthyronin (T3), thyroxine (T4). thyroid-stimulating hormone (TSH). and fasting plasma insulin: height and bone age were also recorded. Dental maturity was determined from panoramic radiographs. The mean difference between the dental and chronological ages was −0.67 ± 0.89 years in the GH-deficient group compared to 0.23 ± 1.07 years in their controls: in the GH non-deficient group the difference was −0.95 ± 0.82 years compared to controls 0.16 ± 1.06 years in their controls. Compared to chronological age. both bone and dental age were lower in the GH-deficient and GH non-deficient groups. It is concluded that children of short stature, both GH-deficient and GH non-deficient, exhibit a delayed dental age compared to their chronological age- and sex-matched controls. A multiple stepwise regression analysts showed that the sitting height and GH level were the only significant factors associated with dental maturity.     

Evaluation of mandibular movements in the horizontal plane made by partial mandibulectomy patients —A pilot study

The purpose of this pilot study of the partial mandibulectomy patient was to make tracings of their mandibular movement in a horizontal plane of orientation in the hope that the results would provide information regarding the prosthetic rehabilitation of these patients. The anterior part of a pantograph recording unit was used in making the tracings. The results of the study indicate that tracings on partial mandibulectomy patients are diagnostic in nature regardless of the range and extent of movement seen. As has been stated by other authors who have studied this type of patient, more clinical research should be undertaken before a full understanding of the ramifications of prosthetic rehabilitation of the partial mandibulectomy patient can be realized.     

Guidelines for the management of traumatic dental injuries. III. Primary teeth

Abstract –  Trauma to the primary dentition present special problems and the management is often different as compared with permanent teeth. An appropriate emergency treatment plan is important for a good prognosis. Guidelines are useful for delivering the best care possible in an efficient manner. The International Association of Dental Traumatology (IADT) has developed a consensus statement after a review of the dental literature and group discussions. Experienced researchers and clinicians from various specialties were included in the group. In cases in which the data did not appear conclusive, recommendations were based on the consensus opinion of the IADT board members. The guidelines represent the current best evidence based on literature research and professional opinion. In this third article out of three, the IADT Guidelines for the management of traumatic injuries in the primary dentition, are presented.     

Clinical evaluation of etched porcelain onlays: a 4-year report

Etched porcelain-bonded-to-enamel restorations (porcelain veneers) have demonstrated a low incidence of debonding, fracture, microleakage, and discoloration. In addition, laboratory and short-term clinical studies have shown satisfactory results with posterior etched porcelain-bonded restorations. This study evaluated the 4-year clinical performance of posterior all-ceramic onlays and overlays bonded with a dual-cure luting resin and a self-cure acetone-based dentinal adhesive. Twenty-one posterior porcelain overlay restorations were fabricated from a high-leucite-content porcelain and bonded to the teeth of 12 adults using a dual-cure luting resin and an acetone-based self-cure N(P-tolyl) glycine-glycdyl methacrylate (NTG-GMA), pyromellitic acid dianhydride and 2-hydroxyethyl methacrylate (PMDM) dentinal adhesive. Restorations were examined for retention, marginal caries, marginal microleakage, sensitivity, discoloration, restorative fracture, and patient satisfaction. Data collected at 4 years revealed 100% retention of the restorations with no marginal discoloration, marginal ditching, caries, or sensitivity. A small gap (Ryge UPHS rating of Bravo) was detected at the facial margin of one restoration but was not sufficient enough to require repair or replacement. Each patient reported a very high level of satisfaction with the restorations. This study demonstrates that porcelain overlays with supragingival margins entirely on enamel that rely primarily or entirely on bonding for their retention can provide excellent esthetics, good function, and perhaps long-term durability if properly designed, fabricated, and bonded. Porcelain overlays fabricated from high-leucite-content porcelain bonded to sound enamel and dentin with a dual-cure luting resin and a fourth generation dentinal adhesive provide satisfactory clinical results and high patient satisfaction.     

Titanium for removable partial dentures (III): 2-year clinical follow-up in an undergraduate programme

This study examined the success of titanium (Ti) removable partial dentures (RPDs) compared with that of cobalt-chromium (Co-Cr) RPDs using a randomized controlled clinical trial. Thirty-eight RPD patients were provided with either Co-Cr (20 patients) or Ti (18 patients) RPDs. The total numbers of dentures was 31 (13 maxillary, 18 mandibular) for Co-Cr and 23 (11 maxillary, 12 mandibular) for Ti. Patients were reviewed for 24 months following denture issue. After the initial 12 months, 20 clinical problems were recorded and became the criteria for subsequent assessment. Incidence of failure was analysed using both Fisher's exact test and the chi square test at a significance level of P<0.05. Fracture of retainers in both metals occurred only in the first 12 months. Some failure types presented at significantly higher levels in the first 12 months but there were no significant differences between the two in all the criteria examined between the 12- and the 24-month reviews. Although differences existed in failure types between Co-Cr and Ti RPDs during the early review stages, the overall success rate of Ti RPDs was comparable with that of Co-Cr RPDs after 24 months. The higher incidence of failures in Ti RPDs prior to the 12-month review suggests the importance of taking its lower rigidity into account when designing RPDs.     

Adsorption from black tea and red wine onto in vitro salivary pellicles studied by ellipsometry

The adsorption of black tea and red wine components onto a pellicle-like protein layer formed in vitro by adsorption from whole unstimulated saliva on hydroxyapatite discs were studied by in situ ellipsometry. It was found that components from black tea readily adsorbed to the pellicle. Subsequent exposure to saliva led to further adsorption of salivary components to give an overall increase in the amounts adsorbed. The amounts adsorbed increased still further following a third tea and saliva exposure. Components of red wine gave significantly greater amounts of adsorption to the pellicle than black tea. The adsorption of components of black tea gave a concomitant increase in colour or stain as measured by a reflectance chromameter. In all cases, the black tea- and red wine-modified pellicles were not eluted by either phosphate buffer or sodium dodecyl sulphate (SDS) rinses. Thus, black tea and red wine components have been shown to have a profound effect on in vitro pellicle maturation, causing thickened layers of stained material to build up, which are not readily removed.     

Mandibular deformity associated with Paget's disease. Case report

Paget's disease (osteitis deformans) and osteoporosis represent the commonest systemic bone disorders. Clinically Paget's disease may be mono-, or polyostotic, and is characterized by excessive and disorganized formation and resorption of bone. It may affect any of the facial bones, most notably the skull and the jaws. A case is described in which the only symptomatic manifestation of Paget's disease was mandibular prognathism. The pathogenesis, aetiology, and management are discussed.