Neonatal permanent jaw constriction because of oral synechiae and Pierre Robin sequence in a child with van der Woude syndrome.

OBJECTIVE: To report a newborn with van der Woude syndrome, Pierre Robin sequence, and oral synechiae. Pierre Robin sequence is a rare manifestation of van der Woude syndrome as are oral synechiae. We speculate that the oral synechiae may be causally related to the development of Pierre Robin sequence in this patient.     

Clinical comparison of an enamel matrix derivative used alone or in combination with a bovine-derived xenograft for the treatment of periodontal osseous defects in humans

BACKGROUND: The combination of bone replacement graft materials has been suggested for the treatment of periodontal osseous defects. The purpose of this study was to evaluate the effectiveness of enamel matrix derivative (EMD) combined with a bovine-derived xenograft (BDX) as compared to EMD alone in the treatment of intraosseous defects in patients with moderate to advanced periodontitis. METHODS: Sixteen adult patients with at least 2 intrabony defects were entered in this split-mouth design study. Defects were treated with EMD alone or EMD + BDX. Reentries were performed 6 to 8 months after initial surgery. The following soft and hard tissue measurements were recorded prior to initial surgery and at reentry: probing depth (PD), gingival margin location, clinical attachment level (CAL), depth of defect, and crestal bone level. Statistical analyses were performed to determine changes in PD, CAL, fill of osseous defect, and crestal resorption. Percentages of bone fill (%BF) and defect resolution (%DR) were also calculated. RESULTS: The most significant results were that gingival recession was greater for the group treated with EMD alone (0.8 +/- 0.8 mm) compared to EMD + BDX (0.3 +/- 0.6 mm) (P = 0.04) and bone fill was greater for EMD + BDX (4.0 +/- 0.8 mm) compared to EMD alone (3.1 +/- 1.0 mm) (P = 0.02). The measures for PD reduction, attachment level gain, crestal resorption, %BF, and %DR did not present a statistically significant difference (P > 0.10). CONCLUSIONS: This study evaluated the performance of EMD + BDX and EMD alone. The results demonstrated that a significant improvement in clinical parameters was observed. When comparing both modalities, a statistically significant difference was only found for gingival recession and bone fill, yielding a more favorable outcome towards the combined approach.     

Aspartate aminotransferase levels in gingival crevicular fluid before and after initial periodontal treatment

The present study investigates the presence of the enzyme aspartate aminotransferase (AST) in the gingival crevicular fluid (GCF) of untreated periodontal patients and determines the alterations in enzyme activity after the initial phase of periodontal treatment. From 12 patients suffering from advanced periodontitis, 54 pockets exhibiting severe attachment loss and depth > 4 mm were selected. Measurements of pocket depth (PD), attachment level (AL) and bleeding upon probing (BOP) were undertaken. For the GCF collection, sterile strips were gently placed at the previously isolated gingival crevice for 30 seconds and afterwards the GCF volume was determined with a Periotron 6000. The AST measurements were based on the establishment absorbency coefficient of NADH. The rate of decrease in the concentration of NADH is directly proportional to the AST activity in the sample. Four weeks after completion of the initial treatment, the patients were re-examined and the same clinical and laboratory measurements were performed. The parameters obtained were statistically analysed. The clinical parameters showed a statistically significant improvement, while the laboratory data expressed a statistically significant decrease of GCF volume as expected. Further, the sites were divided in two groups--pathological (pi) and physiological (phi)--according to Persson and Page (1991). After treatment a marked improvement concerning these values was noticed and it was noteworthy that these alterations occured regardless of initial AST presence.     

Genotypes of mutans streptococci tend to persist in their host for several years

The aim of this study was to evaluate the consistency of the prevalence of mutans streptococci in a group of Swedish families. Eleven families, which had previously been examined for genotypes of mutans streptococci, were re-examined after 2-5 years. The families consisted of mother, father and a child (mean age 7.2 years at the follow-up examination). One father did not participate. Pooled plaque samples were obtained from buccal and occlusal surfaces. Isolates of mutans streptococci were genotyped using chromosomal DNA digested with restriction endonuclease HaeIII, separated by gel electrophoresis and visualised through UV illumination after ethidium bromide staining. Comparing the DNA fingerprints of mutans streptococci found at baseline and follow-up, 9 children harboured one or two genotypes which were similar on the two sampling occasions. Two of these children had also gained a genotype. The remaining 2 children had lost a genotype each and 1 of them had gained two new genotypes. All 21 adults showed one or two genotypes identical to those found at baseline. Nine of these 21 adults had also lost one genotype. Four of these 9 and additionally 4 of the remaining adults showed one or two new genotypes. Six mother-child pairs shared a genotype at baseline and this pattern remained for five pairs at the end of the study. The results suggest that genotypes of mutans streptococci have a fairly high degree of consistency in children between 3 and 8 years of age as well as in adults, indicating persistence of the strains. However, the results also indicate that some subjects may gain and/or lose genotypes.     

Dental resin composites containing ceramic whiskers and precured glass ionomer particles.

OBJECTIVES: Glass ionomer, resin-modified glass ionomer, and compomer materials are susceptible to brittle fracture and are inadequate for use in large stress-bearing posterior restorations. The aim of this study was to use ceramic single crystal whiskers to reinforce composites formulated with precured glass ionomer, and to examine the effects of whisker-to-precured glass ionomer mass ratio on mechanical properties, fluoride release, and polishability of the composites. METHODS: Silica particles were fused onto silicon nitride whiskers to facilitate silanization and to improve whisker retention in the matrix. Hardened glass ionomer was ground into a fine powder, mixed with whiskers, and used as fillers for a dental resin. Four control materials were also tested: a glass ionomer, a resin-modified glass ionomer, a compomer, and a hybrid composite. A three-point flexural test was used to measure flexural strength, modulus, and work-of-fracture. A fluoride ion-selective electrode was used to measure fluoride release. Composite surfaces polished simulating clinical procedures were examined by SEM and profilometry. RESULTS: At whisker/(whisker + precured glass ionomer) mass fractions of 1.0 and 0.91, the whisker composite had a flexural strength in MPa (mean (SD); n = 6) of (196 (10)) and (150 (16)), respectively, compared to (15 (7)) for glass ionomer, (39 (8)) for resin-modified glass ionomer, (89 (18)) for compomer, and (120 (16)) for hybrid composite. The whisker composite had a cumulative fluoride release of nearly 20% of that of the glass ionomer after 90 days. The whisker composites had surface roughness comparable to the hybrid resin composite. SIGNIFICANCE: Composites filled with precured glass ionomer particles and whiskers exhibit moderate fluoride release with improved mechanical properties; the whisker-to-glass ionomer ratio is a key microstructural parameter that controls fluoride release and mechanical properties.     

Cross-cultural differences of self-reported oral health behaviour in Japanese and Finnish dental students

OBJECTIVE: To determine whether any differences existed in dental health behaviour between Japanese and Finnish dental students. SETTING: Hiroshima University School of Dentistry and the University of Helsinki. DESIGN: Comparison of cross-cultural differences of self-reported oral health behaviour. SUBJECTS: Dental students, 337 in Japan and 113 in Finland. METHOD: Subjects were surveyed using the Japanese and Finnish versions of a 20-item questionnaire entitled Hiroshima University--Dental Behavioural Inventory (HU-DBI). RESULTS: Only 2 per cent of Finnish students reported that they put off going to the dentist until they had toothache, compared to 56 per cent of Japanese students. Similarly, significantly more Japanese students thought that their teeth were getting worse despite their daily brushing, compared to their Finnish peers. The mean HU-DBI score of Year 1 Finnish students was higher than that of their Japanese peers, which suggested a higher level of dental health awareness in Finnish students upon entry into dental school. The mean scores of the Japanese students were lower than those of their Finnish peers until Year 3. The mean scores of Year 5 and Year 6 Japanese students were higher than that of Year 1 students, indicating raised self-care levels influenced by the course in preventive dentistry. The gender difference of the HU-DBI score was not a major feature in either country. CONCLUSIONS: Self-reported oral health behaviours seemed to be very different between the two countries, which reflected different culture and/or health education systems of the students.     

Early craniofacial morphology and growth in children with nonsyndromic Robin Sequence.

PURPOSE: Craniofacial morphology and growth comparisons in children with untreated nonsyndromic Robin Sequence (RS) and a control group with unilateral incomplete cleft lip (UICL) in which the lip was surgically closed at 2 months of age. MATERIAL: The 52 children (7 RS and 45 UICL) included in the study were drawn from a group representing all Danish cleft children born 1976 through 1981. The ages of the children were 2 and 22 months at the time of examination 1 and 2, respectively. METHOD: The method of investigation was three-projection cephalometry. Craniofacial morphology was analyzed by means of linear, angular, and area variables. Growth at a specific anatomical location in a patient was defined as the displacement vector from the coordinate of the corresponding landmark at examination 1 to its coordinate at examination 2. RESULTS: The most striking findings in the RS group were markedly increased posterior maxillary width, increased width of the nasal cavity, short maxilla with reduced posterior height, short mandible, bimaxillary retrognathia, and severe reduction in size of the pharyngeal airway. The amount of facial growth was similar in the two groups; however, a tendency toward a more vertical growth direction was observed in the RS group. CONCLUSION: Facial morphology in children with RS differed significantly from that of children with UICL at both 2 and 22 months of age. The magnitude of facial growth was similar in the two groups, whereas a tendency toward a more vertical facial growth direction was observed in the RS group.     

Median ages of eruption of the primary teeth in white and Hispanic children from Arizona

PURPOSE: The purpose of this project was to establish median eruption ages of primary teeth and evaluate eruption differences between contralateral teeth by gender, ethnicity, and household income. Data was derived from a caries study of preschool children. METHODS: A total of 4,277 white (non-Hispanic) and Hispanic preschool children from Arizona were visually examined for caries and tooth eruption status by 5 examiners between February 1994 and September 1995. Analyses of eruption status were conducted using logistic regression to produce an eruption probability distribution from which median eruption ages for the primary teeth were determined. Possible differences in eruption timing between contralateral teeth by gender, ethnicity, and household income were examined. RESULTS: Eruption status of 1 tooth was significantly predictive of the pair-matched tooth for all pairs. Differences were found for the maxillary central incisor (gender) and the mandibular second molar (ethnicity). Eruption ages did not vary by household income. Median eruption ages for each of the 10 primary teeth are presented. CONCLUSIONS: This study provides contemporary median eruption ages for primary teeth.     

A clinical investigation of the tooth whitening efficacy of a new hydrogen peroxide-containing dentifrice

OBJECTIVE: The objective of this four-week, double-blind clinical study was to assess the tooth whitening efficacy of a new dentifrice delivering 1.0% hydrogen peroxide, 0.243% sodium fluoride, and sodium tripolyphosphate in a high-cleaning silica base (Test Dentifrice), relative to that of a control dentifrice containing 0.243% sodium fluoride in a silica base (Control Dentifrice). METHODOLOGY: Following a baseline oral soft tissue examination and tooth shade assessment using the Vita Shade Guide, qualifying adult male and female subjects from the New Delhi, India area were randomized into either the Test or Control Dentifrice group. The two groups were balanced for baseline mean Vita Shade Guide rank scores. All subjects were provided with their assigned dentifrice and a soft-bristled adult toothbrush for home use. Subjects were instructed to brush their teeth for two minutes twice daily (morning and evening), using only the dentifrice provided, and to refrain from using any other oral hygiene products for the entire four weeks of the study. There were no restrictions regarding diet or smoking habits during the course of the study. Oral soft tissue and tooth shade evaluations for each subject were repeated after two and four weeks of product use. RESULTS: Forty-four (44) subjects complied with the protocol and completed the entire study. At the two- and four-week examinations, the Test Dentifrice group had statistically significant mean shade rank score reductions of 4.04 and 5.17, respectively, compared to baseline (p < 0.05), while the Control Dentifrice had respective reductions of 0.41 and 0.53, which were also statistically significant. The mean shade rank reductions in the Test group compared to those in the Control group at two and four weeks were 3.63 and 4.64, respectively, and were statistically significant (p < 0.05). CONCLUSION: A new whitening dentifrice delivering 1.0% hydrogen peroxide, 0.243% sodium fluoride and sodium tripolyphosphate has significant tooth whitening effectiveness, producing a mean shade rank score reduction from baseline of 5.17 after four weeks' use.     

Surgical-prosthodontic reconstruction of advanced maxillary bone compromise with autogenous onlay block bone grafts and osseointegrated endosseous implants: a 12-year study of 32 consecutive patients

During a 12-year period (1984 to 1997), 32 consecutive patients with advanced maxillary bone compromise received surgical-prosthodontic rehabilitation. The most frequent procedure used was maxillary augmentation with a free nonvascularized autogenous onlay block bone graft, and the average time of prosthesis function was 67 months. Twenty-eight patients underwent a 1-stage procedure, in which endosseous implants were placed simultaneously for internal rigid skeletal fixation of the onlay bone graft, and 4 patients underwent a 2-stage procedure, in which endosseous implants were placed secondarily 6 months after complete healing of the previously placed onlay bone graft, which initially was stabilized by titanium miniplates and lag screws. Treatment success was evaluated separately for the first 7 consecutively treated patients (developmental group) and for the next 25 consecutive patients (routine group). Assessment was made of implant survival relative to etiology of bone loss, implant type and length, type of prosthesis, type of opposing occlusion, type of surgical procedure, and presence of discontinuity. The implant survival rate was 91% in the 25 routine patients and 65% in the 7 developmental patients. Implant type and length, prosthesis type, opposing occlusion, and the presence or absence of discontinuity significantly impacted treatment outcome. Onlay block bone graft success (96%) in all 32 treated patients and prosthetic success (96%) in the last 25 patients was recorded.