Dentin adhesion and microleakage of a resin-based calcium phosphate pulp capping and basing cement

An experimental resin-based bioactive calcium phosphate cement, intended as a pulp capping and basing material, was evaluated for dentin shear bond strength and microleakage. The interfacial morphology was examined by scanning electron microscopy (SEM). For microleakage, dentin cavities without (Group A) or after (Group B) acid etching were restored with the calcium phosphate cement. A resin-based calcium hydroxide (VLC Dycal; Group C) was used as control material according to the manufacturer's instructions. After water storage and thermocycling, the microleakage was scored using a AgNO(3) staining procedure. For the shear bond strength, flat exposed dentin surfaces were treated as for the microleakage test. Metal irises pressed against the dentin surface were filled with the cements, which were photocured. Both tests were carried out after 1 wk. While acid etching did not result in significantly greater microleakage, it led to higher shear bond strength, and allowed, as shown by SEM, the formation of a hybrid layer and resin tags. Both groups treated with the calcium phosphate cement had significantly lower microleakage scores and higher mean shear bond strength values than the groups treated with the control material.     

Insoluble zinc, cupric and tin pyrophosphates inhibit the formation of volatile sulphur compounds

Oral malodour is mainly a result of the production of volatile sulphur compounds (VSC). The present study was concerned with investigating the anti-VSC effect of insoluble pyrophosphates (PP) of zinc, copper(II) and tin(II). The hypothesis to be tested was that the sulphide anions produced when VSC are solubilized in water have a higher affinity for the respective metal ions than the PP anion. The anti-VSC effects of insoluble PP were compared with the corresponding soluble metal salts using three in vitro methods: saliva putrefaction; dialysis of a suspension of PP and saliva against water; and analysis of water containing hydrogen sulphide and methyl mercaptan gases, and gases in the headspace. The levels of VSC were analysed by gas chromatography in the first and third methods, and released metal ions were analysed by atomic absorption spectroscopy in the second. The results showed that: the insoluble metal PP inhibited VSC formation in saliva by 99-100%; under dialysis, only minute amounts of metal ions are released from the combination of PP and saliva; and the PP lost their metal cations in water containing dissolved gases and inhibited VSC formation. Hence, the results support the experimental hypothesis. Sulphide ions are obviously very strong ligands for these metal ions.     

Implant-prosthetic rehabilitation after excision of hard palate gland carcinoma

In Summer 2002, a patient with frequent epistaxis was admitted to the San Gerardo Hospital. Local examination showed a big mass in the nasal fossa. TC and RMN revealed a diffuse erosion of the palatal bone and infiltration of the maxilla. The tumor was removed and histological examination showed a gland carcinoma. The young age of the patient and the need of an adequate bone reconstruction led to use osteoperiosteal calf bone graft. Subsequently, using local anesthesia, 6 implants were positioned. After normal healing and the period of osteointegration, a Toronto bridge was made on implants that the patient wears with no problem.     

Oral-facial-digital syndrome type I. A case report

Oral-facial-digital syndrome type I (OFDI) is a congenital X-linked dominant disorder characterized by anomalies of the oral cavity, face and digits sometimes associated to cerebral malformations and polycystic kidney disease. The gene, responsible for this syndrome, is ofd1. Clinically it is seen only in females. Lesions of the mouth include median pseudoclefting of the upper lip, clefts of the palate and tongue, and dental anomalies (missing or supernumerary teeth, enamel hypoplasia, and teeth malpositions). Dysmorphic features affecting the head include hypertelorism, frontal bossing, micrognathia, facial asymmetry and broadened nasal ridge. The digital abnormalities are syndactyly, clinodactyly, brachydactyly and, rarely, pre or post-axial polydactyly. Less frequently ex-pressed phenotypic anomalies include skin milia, alopecia, deafness and trembling. Sometimes the diagnosis of OFDI can be difficult because there is an overlap with other types of oral-facial-digital syndromes. A sporadic case of OFDI, with 7 lower incisors, both in the primary and permanent dentition, is reported. This dental anomaly is very unusual because in literature only supernumerary cuspids are reported. In the light of this case, the authors discuss the oral phenotypic expression of ofd1 gene and its role in human odontogenesis.     

The effect of chlorhexidine gluconate as an endodontic irrigant on the apical seal: long-term results

The purpose of this study was to determine whether chlorhexidine gluconate (0.12%), used as an endodontic irrigating solution, would affect the apical seal of three root canal cements. One hundred, extracted, human, single-canal teeth were divided into 9 experimental groups of 10 teeth each, in addition to a positive and negative control group of 5 teeth each. The teeth were decoronated at the level of the CEJ, accessed, instrumented to a Master apical file #50, irrigated with either sterile saline, 5.25% NaOCl, or 0.12% chlorhexidine gluconate, and dried using paper points. Obturation was accomplished using lateral condensation and one of three endodontic sealers: Roth's 811, AH 26, or Sealapex. Postobturation apical leakage was measured at 270- and 360-day observation periods using the fluid filtration method. Using the mixed-model repeated-measures ANOVA test with Tukey's honest significance difference multiple comparison procedure, the results showed the saline-Sealapex combination had significantly more leakage (p < 0.05) than either the Peridex-Sealapex or saline-Roth's combinations at 270 days. No other significant differences were noted between any sealer-irrigant combination at 270 days. The saline-Sealapex combination had significantly more leakage than the saline-Roth's combination at 360 days. No other significant differences were noted at 360 days. Under the conditions of this study, chlorhexidine gluconate irrigant did not adversely affect the apical seal of three root canal cements at 270 and 360 days.     

The interleukin-1 polymorphism,smoking, and the risk of periodontal disease in the population-based SHIP study

Several studies have shown a role for interleukin-1 gene cluster polymorphisms in the risk assessment for periodontal diseases. In the Study of Health in Pomerania (SHIP), 3148 subjects were randomly selected from the population and assessed for a broad range of diseases and environmental/behavioral risk factors. From the complete study group in the age 40 to 60 years, N = 1085 subjects were genotyped for the interleukin-1 genotype composite polymorphism in relation to periodontal parameters. The study objective was to elucidate the gene-environment interaction between the risk factors smoking and IL-1 polymorphism. An increased risk of periodontal disease was found for IL-1 genotype-positive smokers: odds ratio adjusted for age, sex, education, and plaque OR = 2.50 (95% C.I. 1.21 to 5.13; p = 0.013). This was not the case with subjects who never smoked: OR = 1.09 (0.73-1.62; p = 0.676). These results support the hypothesis of gene-environmental interaction in periodontitis.     

In vitro antimicrobial activity of various medication preparations on E. faecalis in root canal dentin

The purpose of this study was to evaluate the antimicrobial activity of several medication preparations in root canal dentin infected with Enterococcus faecalis. Roots of extracted bovine incisors were prepared to standardized cylindrical test specimens, 5 mm in height. The smear layer was removed and the samples were autoclaved and then incubated at 37 degrees C/5% CO2 for 24 h in brain-heart infusion (BHI) broth containing 7.0 x 10(4) colony forming units per ml of E. faecalis. The samples were washed in phosphate buffered saline and mounted to individual culture wells with sticky wax. Test medications were applied to fill the canal lumina; medication groups were: (a) sterile H2O (positive control); (b) a 10% mixture of 1.0 g Ca(OH)2 USP in 10 ml sterile H2O; (c) 10% Ca(OH)2 in 0.12% chlorhexidine gluconate (Peridex); (d) Peridex; and (e) uninoculated BHI (negative control). The samples were incubated at 37 degrees C/5% CO2 for 24 h. Dentin samples for quantitative microbiology were then obtained with consecutive sterile burs (ISO 029, 035, 042). All three experimental groups demonstrated significantly greater antimicrobial activity than the positive control (p < 0.001). Group 2 demonstrated significantly greater antimicrobial activity than Group 3 or Group 4 at all dentin depths (p < 0.05). These results suggest that 10% Ca(OH)2 may be more effective than Peridex or 10% Ca(OH)2 in Peridex for the elimination of E. faecalis from dentin tubules.     

Arteriovenous malformation in the temporalis muscle

An 18-year-old man presented with an arteriovenous malformation (AVM) in the temporalis muscle. It was shown by magnetic resonance imaging (MRI) and confirmed by intra-arterial angiography. The lesion was completely resected and the defect reconstructed with titanium mesh and cancellous bone.     

Perioperative corticosteroid supplementation and dento-alveolar surgery

Patients are referred to hospital for dento-alveolar surgical procedures requiring supplemental corticosteroid administration. However, it has been reported that medically compromised patients who require routine dental treatment are being referred unnecessarily. This article reports a retrospective study undertaken at a Regional Maxillofacial Unit over a 24-month period, which reveals the referral pattern and management of patients specifically referred for outpatient dental treatment with corticosteroid supplementation. The paper highlights the dilemma confronting practitioners when reviewing the literature on corticosteroid supplementation and the confusion that still exists in both the primary and secondary care settings as to which patients should be prescribed supplemental corticosteroids. A simplified guide is proposed for the clinical management of these patients.     

Factors affecting outcomes of traumatically extruded permanent teeth in children

PURPOSE: The objectives of the present study were to determine the prevalence of residual extrusion, pulpal necrosis, and resorption for extruded permanent teeth and to establish the effect of presentation and treatment factors. METHODS: Seventy-two traumatically extruded permanent incisors were studied at the Departments of Paediatric Dentistry in Belfast, Newcastle upon Tyne, and Glasgow. The mean age of the patients was 10.1 years (range=6 to 18 years). Clinical and radiographic outcomes were analyzed and related to presenting and treatment factors. RESULTS: The initial degree of extrusion was moderate for 46 teeth (64%), and the median delay prior to repositioning was 3 hours (range=1 to 168 hours). Pulp necrosis occurred in 31 teeth (43%), residual extrusion was present in 16 teeth (23%), and inflammatory resorption occurred in 11 teeth (15%). Residual extrusion was significantly associated with a delay in repositioning the tooth, pulpal necrosis was significantly more common in teeth with closed apices and in severely extruded teeth, and inflammatory resorption was more common after pulpal necrosis. CONCLUSIONS: Residual extrusion could be minimized by earlier presentation and repositioning. The risk of pulpal necrosis is greatest for severely extruded teeth and for those with closed apices.