Severe periodontitis in a 5-year-old girl with hyperimmunoglobulin E syndrome.

The hyperimmunoglobulin E syndrome (HIES) is a multisystem disorder that affects the: (1) dentition; (2) skeleton; (3) connective tissues; and (4) immune system. Little is known about periodontal manifestations of the syndrome. The purpose of this report was to describe a 5-year-old girl with suspected autosomal-recessive HIES syndrome who revealed profusely bleeding and painful gingiva and generalized aggressive periodontitis. A polymerase chain reaction (PCR)-based microbiological examination detected Porphyromonas gingivalis, Tannerella forsythia, Prevotella nigrescens, Treponema denticola, Eikenella corrodens, and Campylobacter rectus in the deep periodontitis lesions. The extraction of all deciduous teeth due to a poor prognosis and risk of systemic infection led to resolution of the oral inflammation. Long-term follow-up is required to determine the periodontal prognosis of the erupting permanent teeth.

Effect of cutting instruments on permeability and morphology of the dentin surface.

There are major differences in morphological detail after cutting the dentin surface among the methods commonly used to prepare dental cavities. The purpose of this study was to compare dentin permeability and the morphology of the dentin surfaces prepared with diamond and carbide steel burs after etching with 6% citric acid. Twenty-four freshly extracted human third molars were sectioned, mounted on plexiglass, and connected to the dentin-permeability measuring apparatus. The permeability of dentin was measured by fluid filtration and expressed as hydraulic conductance. There were two study groups of 12 teeth. Each tooth had one occlusal cavity preparation prepared but utilized three depths: the original was prepared just into the dentin, the second 0.5 mm deeper than the first, and the third 0.5 mm deeper than the second. One group had the first cavity prepared with a diamond, the second deepened using a steel bur, then the third depth was made by use of the diamond. The other group had the first cavity preparation prepared with a steel bur, deepened 0.5 mm again using a diamond, then deepened again using a steel bur. Dentin permeability was measured after cavity preparation, then after 2 minutes of acid etching. Analysis of variance and Duncan's multiple range test were used to establish whether differences were significant at the 0.05 confidence level. Prepared and acid-etched surfaces were characterized using a scanning electron microscope to identify any differences between the two groups. After acid etching with 6% citric acid, the permeability of dentin cavities prepared with diamond burs was significantly less than the permeability of cavities prepared with carbide steel burs. After etching, there were differences in the appearance of the dentin surfaces prepared with diamonds and steel burs. Dentin bonding agents may have their effectiveness reduced when placed following cavity preparation by use of a diamond.

Effects of calcium phosphate solutions on dentin permeability.

Calcium phosphate solutions at various concentrations and pH levels were used to obstruct the dentinal tubules. The effects were evaluated by measurements of permeability through dentin discs and by scanning electron microscopy. Precipitation kinetics were followed by pH changes in the solutions and products were determined by X-ray powder diffraction. The solutions were applied in two ways: (a) calcium and phosphate solutions were mixed before application and (b) one solution (calcium or phosphate) was applied first followed by the other solution. Three kinds of human dentin discs were used; one with smear layer and the other two with tubules exposed by sonication or etched by acid. The high concentration calcium phosphate solutions at pH = 9.5 rapidly precipitated amorphous calcium phosphates that obstructed the dentinal tubules and decreased dentin permeability by 85% or more. At pH = 5.6, the calcium phosphate solutions precipitated large crystals of dicalcium phosphate dihydrate. In this case, the effectiveness in obstructing dentinal tubules was found to be procedure sensitive.

Tissue-space emphysema, tissue necrosis, and infection following use of compressed air during pulp therapy: case report.

The intraoperative development of tissue-space emphysema in a child undergoing restorative treatment under general anesthesia is presented. Emphysema development seems to be concomitant with the use of compressed air around patent root canals, complicated by tissue destruction due to movement of canal irrigants/medicaments into the periapical tissues and by secondary infection. Several recommendations for the prevention of tissue-space emphysema are presented including the use of a rubber dam, judicious use of compressed air, and maintenance of canal irrigants and medicaments within the root canal. Treatment recommendations vary from palliative care with follow up in cases of facial emphysema to immediate medical attention in cases of pharyngeal or mediastinal emphysema.

Clinical evaluation of a restoration containing fluoride: two-year results.

Fluoride-containing restorations were placed on the distal surface of primary second molars to evaluate their effectiveness in controlling caries on the mesial surface of the approximating permanent first molars. A half-mouth study design was used with the control primary second molars in the same arch, either restored with amalgam or left sound. After two years, radiographs of 56 pairs of permanent first molars in 48 children were evaluated independently by three examiners blind to whether they were examining study or control surfaces. In 15 matched pairs, the study restoration had the effect of preventing a carious lesion on the mesial surface of a permanent first molar. In six matched pairs, the study restoration had the effect of not preventing progression of a carious lesion on the mesial surface of a permanent first molar. In 35 matched pairs, there was no effect observed. At the two-year evaluation, the study restorations with added fluoride controlled caries progression significantly on the adjacent mesial surfaces of permanent first molars when compared to the controls using the Sign test (P less than 0.05).

Dentin permeability and bond strengths after various surface treatments.

Numerous reports suggest that removal of the smear layer increases the bond strengths of some dentin adhesives while lowering the bond strengths of others. Smear layer removal also increases dentin permeability and wetness. The purpose of this study was to compare the permeability and shear bond strengths of occlusal vs. buccal dentin before and after removal of the smear layer with 6% citric acid and before and after substitution of the smear layer by topical oxalate treatment. Shear bond strengths of Scotchbond/Silux to smear layers were higher than those to acid-etched dentin. Oxalate treatment of acid-etched dentin increased bond strengths to levels that were higher than smear layer controls. Removal of the smear layer increased dentin permeability. This result was completely reversed by oxalate treatment.

Regional variability in the permeability of human dentine.

This was measured qualitatively by using dyes and quantitatively by hydraulic conductance in dentine discs and crown segments in vitro. Both types of preparation demonstrated large regional differences in permeability, with the highest values at the periphery and the lowest in the centre of the disc or crown. As dentine permeability may vary 3-10-fold across a few millimetres, investigators should use as large a surface area as possible to compensate for these regional differences.

The lateral tongue reflex in human neonates.

We undertook an investigation of the lateral tongue reflex to determine whether reflex sensitivity was systematically related to selected perinatal factors. The subjects were 24 male and 27 female newborns with a mean age of 28.9 hr. (SD = 16.8, range 5--72 hr.). The lateral tongue reflex was elicited by applying tactile stimulation of varying intensity to the lateral edge of the tongue approximately 1 cm off midline. Eight different stimuli from the Semmes-Weinstein esthesiometer were used; forces ranged from 68 mg to 3.6 gm. A total of 32 stimulations were given in two repetitions of 16 each (8 on the right side and 8 on the left side). The mean number of positive responses was 19.9 (SD = 3.2, range 13--25), with a 5% response at the lowest level of stimulation and a 100% response at the highest level. There were not differences in total number of positive responses or thresholds on the right and left sides, or in Repetitions I and II. There were no differences between males and females, vaginally and caesarian delivered infants, or resuscitated and non-resuscitated infants. No systematic differences were observed as a function of length of labor, obstetric medications, postnatal age at time of testing, Apgar scores, birth weight, or gestational age. The results suggest that the lateral tongue reflex is a stable and reproducible response that could be used to measure oral sensation, both in normal neonates and in subjects with various anatomical and/or neurosensory deficits.