Quintessence International, 07/2012

Objective: Predictable coverage of multiple adjacent gingival recessions (MAGRs) is a major challenge for clinicians. Although several surgical techniques have been proposed to treat MAGR, it is still unclear as to what extent the proposed approaches may lead to predictable root coverage. The aim of this article is to identify the predictability of the available surgical techniques used to achieve complete root coverage (CRC) of Miller Class I, II, and III MAGRs. Method and Materials: A search of the PubMed database was performed. Additional hand searching and a search for gray literature were also conducted. Due to the heterogeneity of the data, no meta-analysis could be performed. Results: The search resulted in the selection of 16 publications analyzed in this review. In Miller Class I and II MAGRs, the coronalIy advanced flap (CAF) and the modified coronally advanced flap (MCAF) yielded a CRC ranging from 74.6% to 89.3% and a mean root coverage (MRC) ranging from 91.5% to 97.27% at 6 to 12 months following surgery. In Miller Class I and II recessions, the results obtained with MCAF were maintained for up to 5 years (CRC ranging from 35% to 85.1%), as indicated by two studies. One study has indicated that MCAF + connective tissue grafting (CTG) may improve the long-term stability of CRC compared with MCAF (35% CRC without CTG vs 52% CRC with CTG). In Miller Class I and II MAGRs, the use of CTG in conjunction with CAF, MCAF, coronally positioned pedicle (CPP), double pedicle graft (DPG), or the supraperiosteal tunnel technique yielded higher CRC or MRC than with bioabsorbable membranes, acellular dermal matrix (ADM), or platelet-rich fibrin (PRF). In Miller Class III MAGRs, the modified coronally advanced tunnel (MCAT) and CTG with and without an enamel matrix derivative resulted in 38% CRC and in 82% to 83% MRC, respectively. Conclusion: The present findings indicate that in Miller Class I and II MAGRs, CAF or MCAF with or without CTG may lead to predictable CRC; the CRC obtained with MCAF were maintained over a period of 5 years; the use of CTG appears to improve the long-term stability of the MCAF; and the use of CTG in conjunction with CAF, MCAF, CPP, DPG, or the supraperiosteal tunnel technique appear to yield higher CRC or MRC than the use of bioabsorbable membranes, ADM, or PRF. Also, MCAT plus CTG appears to represent a valuable technique for the treatment of Miller Class III MAGRs. Keywords: coronally advanced flap, multiple adjacent gingival recessions, pedicle flap, root coverage, soft tissue grafts, tunnel

Objectives: Passive fit between restorations and implants is considered a significant factor in preventing mechanical and biologic failures in implant dentistry. Since impression taking and master cast fabrication have been shown to cause substantial errors, it was the aim of this study to evaluate the effect of intraoral scanning on the passivity of fit of three-unit cement-retained implant-supported fixed dental prostheses (FDPs). Method and Materials: Conventional and optical impressions (n = 10) of an in vitro situation with two implants in the mandibular left quadrant were made. Based on the scans, 10 FDP frameworks were CAD/CAM fabricated from zirconia ceramic; stereolithographic casts were also made. On both the stereolithographic casts and the casts obtained from the conventional impressions, 10 frameworks were waxed and cast in dental training alloy. Subsequently, all samples were cemented on the in vitro model, while the strains emerging were recorded for statistical analysis (MANOVA with Pillai trace; ß = .05). Results: The restorations fabricated on the stereolithographic casts showed significantly lower levels of strain than the conventionally fabricated ones (P = .013). No significant difference could be found between conventionally and CAD/CAM-fabricated frameworks (P = .080). Conclusion: Intraoral digitization of dental implants appears to be at least as precise as conventional impression taking and master cast fabrication using prefabricated transfer components and laboratory analogs. Keywords: CAD/CAM, impression, passive fit, strain development

Objective: To perform a literature review on peri-implant metastases and primary malignoma and report a case of a pulmonary metastasis around dental implants of the anterior mandibular jaw that mimicked peri-implantitis. Method and Materials: A literature search of publications from June 1980 to June 2011 in the PubMed/ Medline database was performed to collect information about the type, incidence, and localization of malignant primary tumors and metastases around dental implants and to evaluate potential risk factors. A descriptive statistic was performed based on the collected data with regard to the type and/or origin of tumor, its localization, and the patient's age and sex. Results: A total of 1,795 articles were considered for evaluation. Peri-implant metastases are described in three articles, and peri-implant primary tumors were found in 14 publications. Of all peri-implant metastases, no associated risk factors are mentioned. Those of the peri-implant tumors are alterations of the peri-implant mucosa (such as oral lichen planus, verrucous leukoplakia, and ulcer). Most of the primary tumors are squamous cell carcinoma. The mean age of the patients with periimplant metastases was 68 years; for the peri-implant primary tumors, it was 71 years. Conclusion: Peri-implant metastases and primary tumors are rare. Every untypical or refractory reaction to the treatment of peri-implantitis is suspicious for malignancy as long as the contrary remains unproven. Keywords: dental implant, numb chin syndrome, peri-implantitis, primary tumor, pulmonary metastasis, risk factors

Objective: To compare the long-term clinical outcomes obtained by the combination of platelet-rich plasma (PRP) and a porous hydroxyapatite at the test site with those obtained from the use of a mixture of hydroxyapatite and saline at the control site in the treatment of human intraosseous defects. Method and Materials: Sixty healthy, nonsmoking subjects diagnosed with chronic periodontitis were included in this study. Using a split-mouth design, intraosseous defects were surgically treated with a combination of PRP and a porous hydroxyapatite or a mixture of hydroxyapatite and saline. Clinical measurements and radiographic evaluation were performed at baseline and 1 and 4 years postoperatively. Results: When compared with baseline, the 1-year results showed no significant changes. However, the 4-year results indicated that while both treatment modalities resulted in significant changes in all clinical parameters (probing depth, relative attachment level, gingival recession, and intraosseous defect fill; P .001), the test group exhibited statistically significant changes compared with the control group: probing depth reduction, 5.8 ± 0.49 mm vs 4.0 ± 0.45 mm (P .0001); clinical attachment gain, 5.4 ± 1.2 mm vs 3.1 ± 1.1 mm (P .0001); and defect fill, 3.2 ± 0.8 mm vs 2.1 ± 0.6 mm (P .0001). Conclusion: Treatment with a combination of PRP and hydroxyapatite compared with hydroxyapatite with saline led to a significantly more favorable clinical improvement in intraosseous periodontal defects. Keywords: bone grafts, growth factors, intraosseous defects, periodontal regeneration, platelet concentrate

The article reports a case of oral proliferative verrucous leukoplakia (OPVL) in a 76-yearold woman, underscoring how an otherwise inconspicuous white plaque lesion can rapidly turn into a phase of verrucous carcinoma and subsequently squamous cell carcinoma. Keywords: leukoplakia, oral proliferative verrucous leukoplakia, squamous cell carcinoma

Objective: To compare circulating and gingival crevicular fluid (GCF) substance P concentrations in well- and poorly controlled type 2 diabetic patients with chronic periodontitis. Method and Materials: Forty-five serum and 90 GCF samples were collected from diabetic patients with periodontal disease, and the concentrations of substance P were quantified by radioimmunoassay. Results: Serum substance P levels were higher in the poorly controlled diabetic group than in patients with good glycemic control (P = .01); within the poorly controlled group, patients with severe attachment levels had the highest circulating substance P levels (P = .02). Additionally, the diseased sites showed higher substance P levels than control sites (P = .0016). The GCF substance P concentrations in diseased sites correlated significantly with clinical findings such as Plaque Index (r = 0.51, P = .001) and bleeding on probing (r = 0.35, P = .029). Conclusion: Within the limits of this study, our preliminary findings indicate that periodontal inflammation may influence circulating and GCF substance P levels in poorly controlled diabetic subjects. Keywords: diabetes, gingival crevicular fluid, neurogenic inflammation, neuropeptides, substance P

The purpose of this article is to report the use of the subepithelial connective tissue graft technique combined with the coronally positioned flap on a composite resin-restored root surface to treat Miller Class I gingival recessions associated with deep cervical abrasions in maxillary central incisors. Clinical measurements, including gingival recession height, probing depth, and bleeding on probing (BoP), were recorded during the preoperative clinical examination and at 2, 6, 12, and 24 months postoperatively. During the follow-up periods, no periodontal pockets or BoP were observed. The periodontal tissue of the teeth presented normal color, texture, and contouring. In addition, it was observed that creeping attachment had occurred on the restoration. This case report shows that this form of treatment can be highly effective and predictable in resolving gingival recession associated with a deep cervical abrasion. Keywords: composite resin, connective tissue, gingival recession, tooth abrasion

Objective: To evaluate the antibacterial activity of adhesive resin incorporating chitosan as well as the adhesive characteristics. Method and Materials: An experimental adhesive was prepared by adding 0.12%, 0.25%, 0.5%, and 1% (w/w) chitosan solution to Single Bond adhesive resin. The solution of chitosan was prepared by dissolving 2 g of chitosan powder in 1 liter of 1% (v/v) acetic acid. Single Bond without chitosan was used as a control. The antibacterial activity was evaluated using a direct contact test against Streptococcus mutans. The viscosity, degree of conversion, pH, and microtensile bond strength (µTBS) values of the experimental adhesives to dentin were evaluated. Data were analyzed using the ANOVA and Tukey tests. Statistical significance was set at the .05 probability level. Results: The antibacterial properties of freshly prepared and aged experimental adhesives incorporating chitosan were found to exhibit an inhibitory effect on the growth of Streptococcus mutans compared with the unmodified adhesive resin (P .05). The viscosity of the experimental adhesives increased with increasing the concentrations of chitosan incorporation into the adhesive. However, the degree of conversion and pH values decreased with increasing the concentrations of chitosan incorporation into the adhesive. Experimental adhesives incorporating 0.12% and 0.25% (w/w) chitosan showed no significant differences in the µTBS values compared with the control (P > .05). However, the incorporation of 0.5% and 1% (w/w) chitosan into the dental adhesive significantly decreased the µTBS (P .05). Conclusion: Adhesive resin that contains 0.12% (w/w) chitosan is a promising antibacterial adhesive that does not adversely affect adhesive properties. Keywords: adhesive properties, antibacterial activity, chitosan, dental caries, microtensile bond strength, viscosity

The aim of this study was to evaluate the bond strength of fiber posts luted with a one-step self-etching adhesive with the push-out test after phosphoric acid conditioning of the root dentin. Thirty-six single-rooted teeth were endodontically treated. Teeth were sectioned perpendicularly to the cementoenamel junction, and a 10-mm post space was prepared with a calibrated bur. Specimens were then divided into three groups according to the adhesive protocol: A, total-etch three steps; B, self-etch one step; and C, 32% phosphoric acid conditioning and self-etch one step. Fiber posts were luted with self-curing resinbased cement. Teeth were cut in 1-mm slices and pushed until failure with an Instron machine. Results were statistically analyzed with the ANOVA and Bonferroni tests (P .05). Two additional specimens from each group were examined under the scanning electron microscope (SEM). The 32% phosphoric acid significantly influenced the push-out bond strength of fiber posts luted with self-etch adhesives (P .05). SEM analysis showed a continuous hybrid layer with resin tags and lateral branches in groups A and C, while group B showed smear layer dissolution with poor infiltration of the tubules. Keywords: bond strength, fiber post, phosphoric acid, push-out, self-etch

Objective: This 6-month, examiner-blind, single-center, randomized, parallel group clinical trial compared the antiplaque and antigingivitis effects of an essential oil-containing mouthrinse with zinc chloride and sodium fluoride (EO) to a 0.05% cetylpyridinium chloride-containing mouthrinse (CPC) also with fluoride. Method and Materials: Four hundred and eight gingivitis subjects were monitored for the primary outcomes of modified Gingival Index (MGI) and Plaque Index (PI) at baseline and 3 and 6 months. Subjects were randomly assigned to 6-month twice a day unsupervised use of EO, CPC, or negative control rinse in conjunction with normal brushing and flossing. Results: EO was always better than CPC at 3 and 6 months considering all parameters. All benefits allowed by EO increased from 3 to 6 months. CPC was better than the negative control at 3 and 6 months with respect to whole mouth plaque, and the proportion of more severe sites (baseline scores > 3) in PI and MGI. At 6 months, CPC did not differ from negative control in relation to whole mouth MGI reduction, proximal MGI reduction, and percentages of sites improved over baseline in PI and MGI. Conclusion: This new EO mouthrinse provided superior clinical benefits to CPC and demonstrated increasing plaque and gingivitis reductions over 6 months. Our findings support the regular long-term use of the EO mouthrinse and selection over a 0.05% CPC rinse for better efficacy. Keywords: cetylpyridinium chloride, clinical trials, essential oil, gingivitis, mouthrinse

Objective: To determine the effect of relatively low strontium concentrations on enamel remineralization and investigate the dose-response effects of strontium and fluoride combinations on the remineralization of artificial caries lesions in vitro. Method and Materials: Artificial caries lesions were created in 135 bovine enamel specimens. Lesion severity was analyzed using transverse microradiography (TMR) and quantitative light-induced fluorescence (QLF). The specimens were randomly assigned to nine treatment groups based on lesion volume after lesion creation, as measured by TMR. Treatment groups were based on a 3 × 3 factorial design (0/0.05/0.1 ppm fluoride and 0/10/15 ppm strontium). Lesions were remineralized at 37°C for 14 days in artificial saliva, which was supplemented or not with NaF and/or SrCl2 × 6H2O. Lesion remineralization was assessed using QLF and TMR. Data were analyzed using ANOVA. Results: For the TMR data, lesion remineralization in the 10 ppm strontium + 0.05 ppm fluoride group was significantly higher than in all other groups (P .05) except the 0 ppm strontium + 0.05 ppm fluoride group (P = .06). The 10 ppm strontium + 0 ppm fluoride group exhibited significantly less remineralization than the 0 ppm strontium + 0 ppm fluoride group (P = .048). For the QLF data, intergroup differences were not the same as for the TMR analysis. The QLF measurement was only moderately correlated with TMR mineral loss (r = -0.37). Conclusion: Strontium alone did not improve the remineralization of artificial caries lesions under the chosen in vitro conditions. However, a synergistic effect between the combination of fluoride and strontium was found at specific concentrations. Keywords: bovine teeth, dental caries, enamel, fluoride, remineralization, strontium