Shantanu Jambhekar

Clinical and histologic outcomes of socket grafting after flapless tooth extraction: A systematic review of randomized controlled clinical trials

STATEMENT OF PROBLEM Several biomaterials and techniques have been reported for socket grafting and alveolar ridge preservation. However, the evidence for clinical and histologic outcomes for socket grafting with different types of materials in flapless extraction is not clear. PURPOSE The purpose of this systematic review was to analyze the outcomes of a socket grafting procedure performed with flapless extraction of teeth in order to determine which graft material results in the least loss of socket dimensions, the maximum amount of vital bone, the least remnant graft material, and the least amount of connective tissue after a minimum of 12 weeks of healing. Secondary outcomes, including the predictability of regenerating deficient buccal bone, necessity of barrier membranes, and coverage with autogenous soft tissue graft, were also evaluated. MATERIAL AND METHODS An electronic search for articles in the English-language literature was performed independently by multiple investigators using a systematic search process with the PubMed search engine. After applying predetermined inclusion and exclusion criteria, the final list of randomized controlled clinical trials (RCTs) for flapless extraction and socket grafting was analyzed to derive results for the various objectives of the study. RESULTS The initial electronic search resulted in 2898 titles. The systematic application of inclusion and exclusion criteria resulted in 32 RCTs studying 1354 sockets, which addressed the clinical and histologic outcomes of flapless extraction with socket grafting and provided dimensional and histologic information at or beyond the 12-week reentry period. From these RCTs, the mean loss of buccolingual width at the ridge crest was lowest for xenografts (1.3 mm), followed by allografts (1.63 mm), alloplasts (2.13 mm), and sockets without any socket grafting (2.79 mm). Only 3 studies reported on loss of width at 3 mm below the ridge crest. The mean loss of buccal wall height from the ridge crest was lowest for xenografts (0.57 mm) and allografts (0.58 mm), followed by alloplasts (0.77 mm) and sockets without any grafting (1.74 mm). The mean histologic outcomes at or beyond the 12-week reentry period revealed the highest vital bone content for sockets grafted with alloplasts (45.53%), followed by sockets with no graft material (41.07%), xenografts (35.72%), and allografts (29.93%). The amount of remnant graft material was highest for sockets grafted with allografts (21.75%), followed by xenografts (19.3%) and alloplasts (13.67%). The highest connective tissue content at the time of reentry was seen for sockets with no grafting (52.53%), followed by allografts (51.03%), xenografts (44.42%), and alloplast (38.39%). Data for new and emerging biomaterials such as cell therapy and tissue regenerative materials were not amenable to calculations because of biomaterial heterogeneity and small sample sizes. CONCLUSIONS After flapless extraction of teeth, and using a minimum healing period of 12 weeks as a temporal measure, xenografts and allografts resulted in the least loss of socket dimensions compared to alloplasts or sockets with no grafting. Histologic outcomes after a minimum of 12 weeks of healing showed that sockets grafted with alloplasts had the maximum amount of vital bone and the least amount of remnant graft material and remnant connective tissue. There is a limited but emerging body of evidence for the predictable regeneration of deficient buccal bone with socket grafting materials, need for barrier membranes, use of tissue engineering, and use of autogenous soft tissue grafts from the palate to cover the socket.

Evaluation of experimental coating to improve the zirconia-veneering ceramic bond strength.

PURPOSE To evaluate the shear bond strength (SBS) between zirconia and veneering ceramic following different surface treatments of zirconia. The efficacy of an experimental zirconia coating to improve the bond strength was also evaluated. MATERIALS AND METHODS Zirconia strips were fabricated and were divided into four groups as per their surface treatment: polished (control), airborne-particle abrasion, laser irradiation, and application of the experimental coating. The surface roughness and the residual monoclinic content were evaluated before and after the respective surface treatments. A scanning electron microscope (SEM) analysis of the experimental surfaces was performed. All specimens were subjected to shear force in a universal testing machine. The SBS values were analyzed with one-way ANOVA followed by Bonferroni post hoc for groupwise comparisons. The fractured specimens were examined to observe the failure mode. RESULTS The SBS (29.17 MPa) and roughness values (0.80) of the experimental coating group were the highest among the groups. The residual monoclinic content was minimal (0.32) when compared to the remaining test groups. SEM analysis revealed a homogenous surface well adhered to an undamaged zirconia base. The other test groups showed destruction of the zirconia surface. The analysis of failure following bond strength testing showed entirely cohesive failures in the veneering ceramic in all study groups. CONCLUSION The experimental zirconia surface coating is a simple technique to increase the microroughness of the zirconia surface, and thereby improve the SBS to the veneering ceramic. It results in the least monoclinic content and produces no structural damage to the zirconia substructure.

An in vitro investigation to compare the surface roughness of auto glazed, reglazed and chair side polished surfaces of Ivoclar and Vita feldspathic porcelain

The change in surface roughness after different surface finishing techniques has attracted the attention of several prosthodontists regarding wear of opposing teeth or restorative material and the strength; plaque retention and appearance of the restoration. However, there is considerable controversy concerning the best methods to achieve the smoothest and strongest porcelain restorations after chair side clinical adjustments. The purpose of this in vitro study was to compare the average surface roughness of a self-glazed surface, a chair side polished surface and a reglazed surface of ceramic. Two feldspathic porcelain, namely VITA VMK94 (Vita Zahnfabrik, Bad Sachingen, Germany) and IVOCLAR CLASSIC (Vivadent AG, FL-9494 Schaan, Liechtenstein) were selected to fabricate 20 specimens of each in the shape of shade guide tabs. A medium-grit diamond rotary cutting instrument was used to remove the glaze layer, and then the surface of half the specimens were re-glazed and the other half were polished using a well-defined sequence of polishing comprising of: Shofu porcelain polishing system, White gloss disc/polishing wheel, Silicone cone with diamond polishing paste and finally with small buff wheel with pumice slurry. The surface roughness (Ra) (μm) of the specimens was evaluated using a profilometer and scanning electron microscope. The data were statistically analyzed by using Student’s t test. The results had shown that there is no statistically significant difference both quantitatively and qualitatively, between the surface roughness of reglazed and chair-side polished surface. In addition, both reglazed and chair-side polished surfaces are better than the autoglazed surface. Within all the groups, there is no significant difference between companies. Polishing an adjusted porcelain surface with the suggested sequence of polishing will lead to a finish similar to a re-glazed surface. Therefore chair-side polishing can be a good alternative to reglazing for finishing adjusted porcelain surface.

Nanoscale silver depositions inhibit microbial colonization and improve biocompatibility of titanium abutments

Although titanium dental implants are biocompatible, exhibit excellent corrosion resistance and high mechanical resistance, the material fails in providing resistance to infection because it exhibits poor antimicrobial activity. To address these issues, we deposited silver onto titanium abutments (Grade 5 titanium discs) using direct current (DC) sputtering and assessed the antimicrobial activity and biocompatibility of the modified implant material. Atomic absorption spectrometry and X-ray photoelectron spectroscopy were employed to investigate the concentration and elemental composition of the deposited silver. As expected, silver deposited using DC plasma was uniform and good control over the deposition could be achieved by varying the sputtering time. Moderate biocompatible responses (up to 69% viability) were observed in primary human gingival fibroblast cells incubated in the presence of Ti sputtered with Ag for 5min. Silver deposited titanium (Ti-Ag) showed excellent antibacterial effects on Pseudomonas aeruginosa and Streptococcus mutans at a very low concentration (Ag content 1.2 and 2.1μg/mm2). However, higher concentration of silver (6μg/mm2) was required to achieve a reduction in cell viability of Staphylococcus aureus and Candida albicans. The silver sputtered Ti abutments could maintain a long-term antibacterial activity as evidenced by the release of silver up to 22days in simulated body fluid. Our study illustrates that silver deposited titanium is indeed a promising candidate for soft tissue integration on dental abutments and prevents initial microbial adhesion.

Total Mandibular Reconstruction and Rehabilitation: A Case Report

T reatment of mandibular discontinuity defects is a great clinical challenge. Partial or complete mandibulectomy is the surgical treatment of choice for patients diagnosed with malignant oral lesions involving the mandible. The use of microvascular grafts to minimize the impairment of function, speech, and esthetics is the mainstay of modern surgical approach of the reconstructive team. Advances in microvascular surgery have provided the surgeon with methods to repair the partially resected mandible with vital bone grafts. Vascularized bone is used for the secondary reconstructions with large defect, where soft tissue is inadequate, or where the recipient bed has been compromised by radiation, chronic infection, or previous surgery. Often, however, reconstruction of the bony defect alone does not guarantee an adequate foundation for successful conventional prosthetic rehabilitation. Osseointegrated implants placed into the microvascularized grafted bone offer an opportunity for improved function and patient satisfaction and have become the preferred treatment modality. A variety of donor sites have been used for this purpose, including the iliac crest, radius, scapula, and fibula. However, currently the microvascular free fibula flap represents a versatile reconstruction method after mandibularablation. The free fibular microvascular flap was one of the earliest osseous free flaps with successful application in large bony defects. Hidalgo was the first to report the use of a fibula vascularized flap for mandibular reconstruction with 100% osseous survival in a series of 13 patients. Some of the documented advantages of using free fibular microvascular flaps are

Reduction of excess cement during cementation of implant-retained crowns: A clinical tip

The osseointegrated implants has changed the treatment methods of edentulous patients. This technical note presents a simple chair side technique to minimize the overflow of cement at the time of cementation with the use of a custom-made abutment replica during the placement of an implant retained crown.

The Anatomic Inter Relationship of the Neurovascular Structures Within the Inferior Alveolar Canal: A Cadaveric and Histological Study

ObjectiveThe location and inter relationship of the structures of the inferior alveolar neurovascular bundle within the mandibular canal has not been clearly defined. The knowledge of the same is important while planning surgeries in the posterior mandible.MethodsEight cadaveric mandibles were dissected and sections were made at the distal aspect of every tooth. The inferior alveolar neurovascular bundle was identified and examined for the location of the inferior alveolar artery, vein and nerve. Hematoxylin and Eosin sections were made for each specimen to confirm the position of these structures.ResultsAll the sections in all the specimens confirmed that a blood vessel lies superior to the nerve. This position appeared consistent in all the positions relative to all the posterior teeth. There was a variation in the bucco-lingual positioning of these structures relative to each other for the various mandibles.ConclusionA blood vessel is found to always lie superior to the inferior alveolar nerve within the mandibular canal. Variations in the inter relationship of the structures is present.SignificanceThis cadaveric study proves that all along the course of the neurovascular bundle, at various cross-sections studied, the inferior nerve is always inferior to a blood vessel. There can be great variations to the positioning of the structures within the neurovascular bundle in the bucco-lingual dimension and also in the exit of the nerve in various mandibles. Knowledge of the location of the structures is of importance during surgical procedures carried out in the vicinity of these structures.

Access to Abutment Screw in Cement Retained Restorations: A Clinical Tip

Abutment screw loosening has been reported to be the most common prosthetic complications occurring in screw retained as well as cement retained implant restorations. Different methods to treat this issue have been reported in the literature so far; however these have their own short-comings. Retrievability of an implant restoration intact becomes a clinical challenge when the restoration is cement retained especially with an angulated abutment. This technique is aimed at accurately determining the position of the abutment screw in 3 dimensional relationships using a vacuum formed clear stent. This technique can be used as a viable protocol for management of screw loosening in cement retained implant restorations.

Zirconia Intra Mucosal Inserts as a Retentive Aid for Maxillary Complete Dentures: A Case Report

Complete dentures fabricated for edentulous patients with resorbed ridges generally have compromised retention and stability. The use of intramucosal inserts in order to aid retention of a maxillary denture has been reported in the past. Zirconia is a tissue compatible biomaterial whose scope and application in dentistry is on the rise. This paper reports the fabrication of zirconia intramucosal inserts and the technique of its incorporation in the maxillary complete denture in order to enhance retention, stability and thereby oral function.