Periodontal Evaluation in Noncarious Cervical Lesions Restored with Resin-modified Glass-Ionomer Cement and Resin Composite: A Randomised Controlled Study

PURPOSE

To assess periodontal parameters of noncarious cervical lesions (NCCLs) restored with glass-ionomer cement (RM-GIC) and composite resin at baseline, three and six months.

MATERIALS AND METHODS

Eighteen patients with bilateral lesions were included in the study. Lesions (1 mm in depth) were randomly restored with each type of restorative material. Probing depth (PD), relative gingival recession (rGR), relative clinical attachment level (rCAL), visible plaque index (VPI) and gingival bleeding index (GBI) were measured.

RESULTS

No statistically significant differences were found when comparing within groups (p > 0.05). However, the intergroup analysis demonstrated a decrease in GR and rCAL gain for teeth restored with the resin-modified glass-ionomer cement (RM-GIC).

CONCLUSION

Both materials behaved similarly when in close contact with periodontal tissues and did not influence periodontal parameters.

Eighteen-month Clinical Study of Universal Adhesives in Noncarious Cervical Lesions

OBJECTIVE

To evaluate the clinical performance of Scotchbond Universal (3M Oral Care) and Prime & Bond Elect (Dentsply Sirona) in the restoration of noncarious cervical lesions (NCCLs).

METHODS AND MATERIALS

This was a randomized controlled clinical trial involving 63 subjects. Two hundred and three NCCLs were restored using Scotchbond Universal and Prime & Bond Elect using both an etch-and-rinse and a self-etch technique. Lesions were notch-shaped NCCLs, and the restorations were placed without any mechanical retention. Restorations were finished immediately after placement and scored with regard to retention, marginal discoloration, marginal adaptation, and secondary caries. Similar assessment of the restorations was performed 18 months after placement. Logistic regression was performed for each outcome separately with a compound symmetric variance-covariance structure assumed to consider a correlation of restorations within subjects. All analyses were conducted using SAS version 9.4 (SAS Inc).

RESULTS

One hundred and fifty-eight teeth (77.8% of the restorations placed) in 46 subjects (73% of subjects enrolled) were available for the 18-month follow-up. A statistically significant difference was reached only for the comparison Scotchbond Universal/self-etch (SU_SE) and Prime & Bond Elect/etch-and-rinse (PBE_E&R) groups ( p=0.01), where a restoration with SU_SE was 66% less likely to maintain a score of Alpha for marginal discoloration than a restoration performed with PBE_E&R.

CONCLUSIONS

Scotchbond Universal and Prime & Bond Elect presented acceptable clinical performance after 18 months of clinical service. However, Scotchbond Universal, when applied with a self-etch approach, did demonstrate a relatively high level of marginal discoloration when compared to the other groups.

Bone and cortical bone thickness of mandibular buccal shelf for mini-screw insertion in adults

OBJECTIVE

To analyze the buccal bone thickness, bone depth, and cortical bone depth of the mandibular buccal shelf (MBS) to determine the most suitable sites of the MBS for mini-screw insertion.

MATERIALS AND METHODS

The sample included cone-beam computed tomographic (CBCT) records of 30 adult subjects (mean age 30.9 ± 7.0 years) evaluated retrospectively. All CBCT examinations were performed with the i-CAT CBCT scanner. Each exam was converted into DICOM format and processed with OsiriX Medical Imaging software. Proper view sections of the MBS were obtained for quantitative and qualitative evaluation of bone characteristics.

RESULTS

Mesial and distal second molar root scan sections showed enough buccal bone for mini-screw insertion. The evaluation of bone depth was performed at 4 and 6 mm buccally to the cementoenamel junction. The mesial root of the mandibular second molar at 4 and 6 mm showed average bone depths of 18.51 mm and 14.14 mm, respectively. The distal root of the mandibular second molar showed average bone depths of 19.91 mm and 16.5 mm, respectively. All sites showed cortical bone depth thickness greater than 2 mm.

CONCLUSIONS

Specific sites of the MBS offer enough bone quantity and adequate bone quality for mini-screw insertion. The insertion site with the optimal anatomic characteristics is the buccal bone corresponding to the distal root of second molar, with screw insertion 4 mm buccal to the cementoenamel junction. Considering the cortical bone thickness of optimal insertion sites, pre-drilling is always recommended in order to avoid high insertion torque.

Surgical repair of invasive cervical root resorption with calcium-enriched mixture cement: a case report

Invasive cervical resorption (ICR) occurs in the cervical area of the teeth due to the formation of a soft tissue that progressively resorbs dentin. The disease is asymptomatic unless the pulp is exposed. This article presents a case involving a mandibular canine that was treated with a calcium-enriched mixture (CEM) cement. After a full mucoperiosteal flap was performed, the soft tissue was curetted away and the cavity filled with CEM biomaterial. One week later, the supragingival surface of the CEM was polished and covered with composite resin. At a 1-year follow-up visit, the pulp was healthy and the gingival probing depth decreased from >3 mm to 1 mm, showing attachment gain. As a biocompatible material, CEM has proven its ability in dentinogenesis, cementogenesis, and osteogenesis; it may prove to be a suitable biomaterial for treating ICR cases.

Surgical management of invasive cervical resorption using resin-modified glass ionomer cement

Invasive cervical resorption is an external resorption that begins below the epithelial attachment. It is caused primarily by dental trauma, orthodontic treatment, or dental bleaching. This case report involved an invasive Class III cervical resorption resulting from trauma to the superior right central incisor. Root canal treatment was followed by surgical intervention. The resorptive defect was debrided, and part of the tooth was restored with resin-modified glass ionomer cement. Postoperative follow-up revealed complete healing and healthy gingival attachment.

Subepithelial connective tissue graft for treatment of gingival recessions with and without enamel matrix derivative: a multicenter, randomized controlled clinical trial

The aim of this multicenter, randomized controlled trial was to compare the clinical outcomes of a connective tissue graft (CTG) alone or in combination with enamel matrix derivative (CTG + EMD) in the treatment of Miller Class I and II gingival recessions. The 56 selected defects were evaluated for probing depth, recession depth, keratinized tissue width, and probing attachment level, and were measured at baseline and 12 months after treatment. The mean recession reduction was 3.9 ± 0.8 mm for EMD-treated sites (test) and 3.6 ± 1.5 mm for the control group (P = .22), corresponding to a mean root coverage of 90% and 80% for test and control groups, respectively (P = .05). Complete root coverage was obtained in 62% of test sites compared to 47% in the control group (P = .27). Both procedures provided good soft tissue coverage. The better results of the test group did not achieve a statistically significant level.

Coronally Repositioning the Cemento-Enamel Junction to Address Gingival Margin Discrepancies

BACKGROUND

Gingival margin discrepancies, especially in the esthetic zone, can pose a challenge for the restorative dentist. Surgical clinical crown lengthening and orthodontic tooth movement are most often used to treat these situations. In this report, an additional surgical technique will be discussed with its indications for use.

METHODS

Three cases are presented, each with a different type of gingival margin discrepancy. The surgical technique used was the same for all cases. It involved establishing a new, more coronally positioned cemento-enamel junction (CEJ) through the use of a finishing bur and curets. The newly exposed root surface was then covered with connective tissue, thus effecting a movement of the gingival margin in a coronal position.

RESULTS

Clinical outcomes resulted in a more natural soft tissue relationship between the treated tooth and the adjacent dentition. The three cases presented did not appear to have any negative periodontal or restorative consequences following the procedure.

CONCLUSIONS

This report presents another technique which can be considered when the clinician is faced with the need to move the gingival margin in a coronal direction. Within the guidelines presented, this technique appears to be predictable, less complicated, and less time consuming to carry out when compared with other available options.

Immunohistochemical study on pulpal response in rat molars after cavity preparation by Er:YAG laser

While Er:YAG laser systems are in extensive use for caries removal and cavity preparation, the effects of such treatment on pulp tissue remain unclear. This study evaluates these systems using immunohistochemical methods and compares the results with information gained from treatment using conventional burs. Cervical cavities were prepared in the upper first molars of rats, using either an Er:YAG laser or a conventional tungsten-carbide bur. At intervals of 5 min, 6 h, 12 h, 1 d, 3 d and 7 d after cavity preparation, the teeth were processed for immunohistochemical analyses of tissue non-specific alkaline phosphatase, OX6-positive major histocompatibility complex class II antigen-expressing cells and PGP 9.5-immunoreactive nerve fibers. DNA fragmentation was detected by the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) method. Tissue non-specific alkaline phosphatase was observed mainly in the subodontoblastic layer under the cavity lesion, from 5 min, in both groups. The immunoreactivity was more pronounced in the laser group, but by 7 d no significant differences were recognizable. At 12 h, TUNEL-positive cells were detected around the odontoblastic layer in both groups. From 3 d to 7 d, a limited number of positive cells were still visible in the group that underwent standard treatment. Clear similarities in the distribution patterns of OX6-immunopositive cells and PGP 9.5-immunoreactive nerve fibers were also noted. From 12 h to 1 d, OX6-positive cells accumulated along the pulp-dentin border, extending their processes into the dentinal tubules. Numerous bead-like PGP 9.5-immunoreactive nerve fibers were observed under the odontoblastic layer at 7 d. These results demonstrated that there was no appreciable difference in the manner in which pulp tissue responded to treatment with either Er:YAG laser or a conventional drill. This would seem to indicate the usefulness of the Er:YAG laser system in the removal of caries and cavity preparation.

Modification of col shape and interproximal area after periodontal surgery associated with the restorative alveolar interface (RAI) technique. Histological study in dogs

The modification of the col shape and position by the restorative alveolar interface technique (RAI) was studied in the interproximal areas between the mandibular first molars and fourth premolars of 10 dogs. Full thickness flaps were raised to expose the interproximal root surface and alveolar bone crest. The RAI procedure was performed only on the experimental sides and the control areas were the opposite side of the same animal. The animals were sacrificed at zero hour, 7, 14, 21 and 28 days for histological analyses. Approximately 6.0-micron-thick sections were made in buccolingual and mesiodistal directions and stained with hematoxylin-eosin and Mallory for light microscopy analysis. A satisfactory healing process was observed up to the 14th and 21st days which showed a modified col shape. At this time, an inflammatory reaction developed affecting the evolution of the healing. The surgery had probably created conditions for the installation of an inflammatory process resulting from the modified anatomy of the interdental area.

Soft tissue root coverage as treatment for cervical abrasion and caries

Root exposure caused by gingival recession may result in cervical abrasion, root caries, root sensitivity, and compromised esthetics. Although cervical root lesions can be treated with Class V restorations, there may be advantages in treating them with soft tissue grafts for root coverage since they restore the dento-gingival unit to its prerecession condition. The rationale for root coverage with soft tissue grafts is reviewed and two cases are presented of successful root coverage procedures in which gingival recession associated with cervical abrasion and caries was present.

Pulpal thermal responses to an erbium,chromium: YSGG pulsed laser hydrokinetic system

PROBLEM

Laser systems are known to raise pulpal temperatures when applied to tooth surfaces. Dental biocalcified tissues can be cut with an erbium,chromium:yttrium-scandium-gallium-garnet laser-powered hydrokinetic system. This device is effective for caries removal and cavity preparation in vitro. Pulpal monitoring of temperature changes during hard tissue cutting by a hydrokinetic system have not been reported.

OBJECTIVES

This study compared the effects of hydrokinetic system, dry bur, and wet bur tooth cutting on pulpal temperature.

STUDY DESIGN

In vivo thermocouple intrapulpal measurements were made on cuspid teeth in anesthetized beagle dogs. In vitro measurements were made on extracted human molar teeth preserved in high-salt solution and later rinsed in phosphate-buffered saline (pH 7.4) to simulate in vivo conditions. The hydrokinetic system was compared with conventional air-turbine-powered bur cutting. The hydrokinetic system cuts and bur preparations were randomly made on the buccal surfaces at the cervical one third of the crown and extended until exposure of the pulp was confirmed clinically.

RESULTS

Pulpal temperatures associated with the hydrokinetic system either showed no change or decreased by up to 2 degrees C. Wet bur preparations resulted in a 3 degrees to 4 degrees C rise. With dry bur preparations, a 14 degrees C rise in temperature was recorded.

CONCLUSIONS

Under the conditions of this study, the erbium,chromium:yttrium-scandium-gallium-garnet laser-powered hydrokinetic system, when used for cavity preparation, had no apparent adverse thermal effect as measured in the pulp space.

The relationship between cervical enamel projection and class II furcation defects in humans

The purposes of the present study were to examine the frequency of cervical enamel projection in mandibular molars with class II furcation defects and to examine the response of these teeth to guided tissue regeneration procedures. Probing depth and vertical and horizontal periodontal attachment levels were recorded with a constant-force electronic periodontal probe. Following surgical exposure of the bifurcation and prior to membrane placement, the cervical enamel projection was examined and then graded clinically; photographs were taken to allow further examination of the bifurcation. An overall improvement in clinical parameters was observed in most sites. Cervical enamel projection was present in 82.1% of all molars examined. Grade II was the most prevalent (34.8%). Patients with any degree of cervical enamel projection demonstrated significantly higher mean probing depths at baseline than did patients without cervical enamel projection. Likewise, pretreatment probing attachment levels were higher in patients with some degree of cervical enamel projection. However, greater posttreatment horizontal and vertical attachment gains were observed in sites with a baseline cervical enamel projection.