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BACKGROUND: Orthodontic treatment is a long-term procedure that involves the usage of brackets and archwires which are mainly metallic in nature. This study evaluated the levels of metal ions release from bonded and nonbonded orthodontic brackets after immersion in distilled deionized water and three different types of mouthwash. MATERIALS AND METHODS: Eighty premolar stainless steel brackets (3M, Unitek) were divided into Group A (bonded brackets) and Group B (nonbonded brackets). Each group was further subdivided into four subgroups to analyze the release of ions from three different types of mouthwash along with the control group. All the samples were incubated at 37°C for 45 days, and immersion solutions were tested in inductively coupled plasma-optical emission spectrometer for the release of free metal ions. RESULTS: Mean ion release in the bonded bracket group was less than that of nonbonded bracket group. Ion release in control subgroup of both groups was 0.18 ± 0.08 µg/dl (A1) and 0.17 ± 0.06 µg/dl (B1); in Phos-Flur mouthwash subgroup was 0.12 ± 0.06 µg/dl (A2) and 0.13 ± 0.05 µg/dl (B2); in chlohex mouthwash subgroup was 0.13 ± 0.06 µg/dl (A3) and 0.14 ± 0.06 µg/dl (B3); in Hiora mouthwash subgroup was 0.10 ± 0.06 µg/dl (A4) and 0.12 ± 0.05 µg/dl (B4). CONCLUSIONS: The mean ion release was the highest in deionized water (control group) followed by chlohex, Phos-Flur, and Hiora in both Group A and Group B. Ion leaching from bonded brackets was less compared to nonbonded brackets in all different mouthwashes except in the control group. However, this difference was statistically insignificant (P > 0.05) between all the groups.

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Desired retrievability of cemented implant-supported fixed prosthesis makes the retentive strength of cementing agents an important consideration. The aim of the study was to evaluate the retentiveness of purposely designed implant cement and compare its retentiveness with dental cements that are commonly used with implant systems. Ten implant analogs were embedded in auto-polymerizing acrylic resin blocks and titanium abutments were attached to them. Fifty standardized copings were waxed directly on the abutment and casted. The cements used were: (1) resin-bonded zinc oxide eugenol cement, (2) purposely designed implant cement, (3) zinc phosphate cement, (4) zinc polycarboxylate cement, and (5) glass ionomer cement. After cementation, each sample was subjected to a pull-out test using universal testing machine and loads required to remove the crowns were recorded. The mean values and standard deviations of cement failure loads were analyzed using ANOVA and Bonferroni test. The mean values (± SD) of loads at failure (n = 10) for various cements were as follows (N): resin-bonded zinc oxide eugenol cement 394.62 (± 9.76), Premier implant cement 333.86 (± 18.91), zinc phosphate cement 629.30 (± 20.65), zinc polycarboxylate cement 810.08 (± 11.52), and glass ionomer cement 750.17 (± 13.78). The results do not suggest that one cement type is better than another, but they do provide a ranking order of the cements regarding their ability to retain the prosthesis and facilitate easy retrievability.

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The field of science and research is ever changing and the scientific discipline of prosthodontics is no exception. The practice of prosthodontics and the supporting technology involved has evolved tremendously from the traditional to the contemporary. As a result of continual developments in technology, new methods of production and new treatment concepts may be expected. Clinicians must have certain basic knowledge if they are to benefit from these new procedures. This article reviews the contemporary trends in the field of prosthodontics and provides an insight into what one might expect in the near future.

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Movement of impression copings inside the impression material using a direct (open tray) impression technique during clinical and laboratory phases may cause inaccuracy in transferring the 3-dimensional spatial orientation of implants intraorally to the cast. Consequently, the prosthesis may require corrective procedures. This in vitro study evaluated the accuracy of 3 different impression techniques using polyether and vinyl polysiloxane (VPS) impression material to obtain a precise cast for multiple internal connection implants. A reference acrylic resin model with 4 internal connection implants was fabricated. Impressions of the reference model were made using 3 different techniques and 2 different impression materials. The study consisted of 24 specimens divided into 6 groups of 4 each. Impressions were poured with ADA type IV stone (Kalrock, Kalabhai Karson Pvt Ltd, Mumbai, India). All casts were evaluated for the positional accuracy (mm) of the implant replica heads using a profile projector. These measurements were compared to the measurements calculated on the reference resin model, which served as a control. Data were analyzed with 2-way analysis of variance (ANOVA) followed by Bonferroni multiple comparison procedures to evaluate group means. The results revealed significant difference for anterior implant distance between the 2 impression materials (P < .01) and also among the 3 different techniques (P < .05). The lowest mean variation was found with the polyether impression material and the splinted technique. For posterior implants, the results suggested no significant difference between the 2 impression materials (P ≥ .05). Although results were not statistically significant, the polyether impression material showed the lowest mean variation as compared to the VPS impression material. However, there was a significant difference among the 3 different techniques (P < .05). Among the 3 different techniques, the lowest mean variation between 2 posterior implants was found in the splinted technique. Casts obtained from impression techniques using square impression copings splinted together with autopolymerizing acrylic resin prior to the impression procedure were more accurate than casts obtained from impressions with nonmodified implant impression copings and with airborne particle-abraded, adhesive-coated copings. Casts obtained from polyether impression material were more accurate than casts obtained from vinyl polysiloxane impression material.

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Diminution of the orbital contents post-surgical removal of a malignant tumor can have a severe psychological impact on the patient in terms of function and esthetics. Therefore, esthetic remedy should be planned subsequently, since tumor obliteration precedes cosmetic concern. A convenient option for successful rehabilitation in such patients is a simple, user-friendly, removable orbital prosthesis. Retention of the prosthesis is one of the key factors for the successful rehabilitation. Spectacle frame, conformers, adhesives, osseointegrated implants, magnets or buttons have been used to impart retention to the prosthesis. The use of semi precision attachments in maxillofacial prostheses is limited to the osseointegrated prostheses. This case report describes a conventional spectacle frame technique, to retain the silicone orbital prosthesis using two different types of stud attachments viz., dalla bona and O-ring attachment systems.

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Crown or root fractures are the most commonly encountered emergencies in the dental clinic. Root fractures occur in fewer than eight percent of the traumatic injuries to permanent teeth. They are broadly classified as horizontal and vertical root fractures. Correct diagnosis of root fractures is essential to ensure a proper treatment plan and hence, the best possible prognosis. Indication of the type of treatment to be used depends primarily on the level of the fracture line. Therefore, a clinician must also have a thorough knowledge of the various treatment approaches to devise a treatment plan accordingly. Various treatment strategies have been proposed, each with their own advantages and disadvantages. Hence, this literature review presents an overview of the various types of root fractures and their management.

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This study compares the internal fit and marginal adaptation of copy milled Zirconia copings with Nickel-Chromium (Ni-Cr) copings fabricated using a lost wax technique before and after ceramic veneering. A standardized metal master die simulating a prepared crown was fabricated and twenty impressions of the metal die were made and poured with die stone. Wax patterns were made on ten dies and cast while light cure resin patterns were made on the other ten dies for copy milling the Zirconia copings. Five specimens from each group were subjected to ceramic veneering. All the test specimens were luted on to the fresh dies, embedded in dental plaster, sectioned and image analysis done using scanning electron microscopy. Thereafter statistical analysis is done using student t-test. The linear measurements for internal fit and marginal discrepancy were increased for Zirconia compared with Ni-Cr copings. The difference in the values of all the specimens of all the groups were not statistically significant (P > 0.05) except the values comparing the internal fit of Zirconia and Ni-Cr copings before ceramic veneering (P < 0.001) which was statistically significant. The internal fit and marginal adaptability of Ni-Cr copings were found to be better than the Copy milled Zirconia copings but internal fit and marginal adaptability deteriorated after ceramic veneering.

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The aim of this preliminary in vitro study was to compare the retentiveness of a luting agent designed for use with dental implants to luting agents designed for use with tooth-retained restorations. The following luting agents were tested: (1) implant cement, (2) resin-bonded zinc oxide-eugenol cement, (3) zinc phosphate cement, (4) zinc polycarboxylate cement, and (5) glass-ionomer cement. After cementation, each sample was subjected to a pull-out test using a universal testing machine, and the loads required to remove the crowns were recorded. The mean values and standard deviations of cement failure loads were analyzed using analysis of variance and the Bonferroni test. The mean cement failure loads (N) were 333.86 ± 18.91 for implant cement, 394.62 ± 9.76 for resin-bonded zinc oxide-eugenol cement, 629.30 ± 20.65 for zinc phosphate cement, 810.08 ± 11.52 for zinc polycarboxylate cement, and 750.17 ± 13.78 for glass-ionomer cement. The retention provided by polycarboxylate cement was significantly greater than that of all other luting agents; the implant cement showed the lowest retention values. These preliminary in vitro observations need to be confirmed under conditions that more closely approximate the clinical environment.

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Dental implants constitute a well-established approach for replacement of lost teeth with titanium being the most favored material for implantation. However, titanium has its limitations in esthetically demanding cases and neither the form nor material of such implants has changed much over the past 40 years. Today, there is scientific evidence that zirconia dental implants osseointegrate well and offer many advantages over titanium implants. This report demonstrates the successful clinical use of a custom milled root analogue zirconia implant for single tooth replacement. A left maxillary first molar was removed, allowed to heal for four months and a custom-made, root-analogue, roughened zirconia was fabricated and placed. Subsequently it was restored with zirconia all ceramic crown. No complications occurred during the healing period. This successful case warrants further clinical research on zirconia custom milled implants in well controlled trials.

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Owing to its excellent biomechanical characteristics, biocompatibility, and bright tooth-like color, zirconia has the potential to become a substitute for titanium as dental implant material and to be successfully used as root-analogue implants by reproducing the contours of the extracted tooth. This article presents an overview of the technique of using root analogue zirconia dental implants as an immediate implantation material. These implants are replicas of the extracted tooth and therefore truly anatomically correct and socket friendly.

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The purpose of this study was to evaluate the clinical efficacy of 3 new gingival retraction systems; Stay-put, Magic foam cord and expasyl, on the basis of their relative ease of handling, time taken for placement, hemorrhage control and the amount of gingival retraction. Thirty subjects were selected requiring fixed prosthesis. The 3 gingival retraction systems were used on the prepared abutments randomly. The time taken for placement of each retraction system was recorded. The vertical gingival retraction was measured before and after retraction using flexible measuring strip with 0.5 mm grading. The horizontal retraction was measured on polyether impressions made before the retraction and after retraction. Based on the results, magic foam cord retraction system can be considered more effective gingival retraction system among the three retraction systems used in the study.

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PURPOSE: Osseointegration being an accepted and well-documented concept, attention is now directed towards simplification of the mechanical design of implants and towards achieving biomechanical success. The aim of this literature review is to provide an overview of the one-piece implant, with its advantages and disadvantages over a conventional two-piece implant. METHODS: The PubMed database was searched in the English language using the keywords one-piece implant, single-piece implant, single-stage implant surgery, and two-piece implant. Articles were selected on the basis of whether they had sufficient information related to placement timing, surgical procedure used, loading protocol, follow-up periods, marginal bone loss, and implant success rates of one-piece implants. For inclusion, a study group must have had a minimum of 30 one-piece implants followed for at least 1 year. DISCUSSION: Nineteen articles were subjected to the selection criteria. Out of 19 clinical trials only 11 met the selection criteria. Five parameters were taken into consideration for studying one-piece implants: placement timing, surgical technique, loading protocol, marginal bone loss, and implant survival rate. The data from the identified studies were tabulated according to these parameters and discussed. CONCLUSION: Delayed placement of one-piece implants is more commonly practiced than extraction and immediate placement. Most surgeons prefer surgeries using flaps as compared to flapless surgeries, and in most cases, one-piece implants were loaded immediately. Limited literature reveals both positive and negative results regarding the effect of a one-piece implant system on surrounding hard and soft tissues.

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OBJECTIVES: The resin-bonded fixed partial dentures have gained immense popularity in recent years as they are more conservative, esthetic, economic and easily fabricated. However debonding is considered the most common cause of failure of resin bonded prosthesis. The objective of the study were to compare the effects of different groove lengths and thickness of retainers on retention of maxillary anterior base metal resin bonded retainers. STUDY DESIGN: Twenty five metal dies of maxillary central incisor duplicated from pure typhodont teeth (maxillary left central incisors) prepared to receive retainer for resin bonded fixed partial denture having different test designs were made. Five test groups were made with each group having five specimens. Two groups were having preparation depth of 0.5mm and retention groove lengths of 3mm and 5mm. Two groups had preparation depths of 0.3 and 0.7mm with no groove preparation with retainer thickness of 0.3 and 0.7mm respectively. Fifth group with no groove preparation and preparation depth of 0.5mm was kept as control for all the groups. All the specimens were cemented using calibra (Dentsply) resin cement. Each specimen was subjected to tensile loading in vertical direction on universal testing machine (Instron 5569) at a crosshead speed of 1mm/min. \ RESULTS: Groups with 5mm and 3mm groove length recorded higher mean vertical forces when compared to the group with no groove preparation. Group with 5mm groove length showed highest mean vertical forces. The group with 0.7mm retainer recorded higher mean vertical force values when compared to groups with 0.5mm and 0.3mm retainer thickness. Group with 0.3mm retainer thickness recorded the least mean vertical force value. CONCLUSION: Placement of the grooves increased the retention values almost 2 ½ times than the grooveless preparation and as the thickness of the retainers increased retention values also increased. Retention value was directly proportional to the groove length and retainer thickness. Key words:Groove length, retainer thickness, resin bonded bridges.

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Radical maxillectomy frequently leads to extended defects in hard and soft tissues that result in a connection between the oral cavities and orbit. If the defect cannot be surgically reconstructed, a combination prosthesis may be necessary to remedy dysfunction in patient function, comfort, esthetics. For minor defects, enlargement of the base of the intra oral prosthesis is generally sufficient. Resections that affect more than one third of the maxilla usually require an intra oral and an extra oral prosthesis that could be assembled and retained in the patient. This clinical report describes a technique of prosthetic rehabilitation of midfacial defect with a silicone orbital prosthesis and intra oral obturator that are retained by magnets. Key words:Combination Prosthesis, Silicone Prosthesis, Magnets, obturators.

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The determination of the occlusal vertical dimension and proper positioning of the anterior teeth are major factors in making complete dentures which will give optimum service. In this study, efforts were made to evaluate the reliability of measurement of vertical distance between the anterosuperior most point on the lingual frenum and mesioincisal edges of mandibular central incisors in natural dentition among different age groups and in complete denture wearers. Three hundred dentulous subjects belonging to different age groups and hundred edentulous patients wearing complete dentures were selected. The dentulous group was divided into three groups, group I (20-40 years), group II (41-60 years), group III (61 years and above) and the edentulous subjects being group IV ( 40-60 years). Mandibular irreversible hydrocolloid impression (Alginate) was made using modified stock tray. In edentulous subjects impression was made with denture in position. The vertical distance between anterosuperior most point on the lingual frenum and mesioincisal edges of mandibular central incisors was measured on the dentulous casts and casts of complete denture wearer using dental surveyor and the vernier calipers. The values were tabulated and statistically analysed. The mean vertical distance between anterosuperior most point on the lingual frenum and mesioincisal edges of mandibular central incisors among dentulous subjects was 12.3 mm and among complete denture wearers was found to be 13.2 mm. There was no significant variation in the mean vertical distance among dentulous subjects belonging to different age groups. At 5 % significance level, statistically there was a significant difference in the mean vertical distance between group I and group IV; group II and group IV.

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Shade selection with the help of shade guides and color matching the restorations to the natural dentition continues to be one of the most perplexing and frustrating problems in fixed prosthodontics. The purpose of the study was to evaluate the shade differences of the natural anterior teeth in different age groups and gender, within the cross sectional Bangalore, Karnataka population, using commercially available shade guides. The shade of a cross section of the population comprising of 400 subjects of both the sexes (800 incisors; 400 maxillary central incisors; 400 mandibular central incisors) visiting the outpatient Department of Government Dental College was selected randomly and evaluated visually by a single observer using three commonly used shade guides i.e. Vita Lumin, Chromascop and the Vita 3D Master. The incidence of the most common shades in the different age groups and gender using these shade guides was obtained and this data was subjected to the χ(2) test (p < 0.05-significant). The most common shade for the maxillary and mandibular incisors in the younger age group is A2/2R1.5/140 and A1/1M2/120 for the males and females using Vita Lumin, Vita 3D Master and Chromascop shade guides respectively. In the advanced age group the most common shade for the maxillary and mandibular incisors is A2/2R2.5/140 using the same order of shade guides. However the results showed no statistical significance in shade variation in males and females in different age groups using different shade guides. Although the incidence of males with darker teeth as compared to females was higher; the study showed no statistical significant correlation between shade differences in both the sexes. It is also observed that there is a significant darkening of teeth as the age advances.

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The purpose of this systematic review was to assess the published data concerning zirconia dental implants from various aspects. To identify relevant literature an electronic search was performed of PubMed. Titles and abstracts were screened and articles that fulfilled the inclusion criteria were selected for a full-text reading. Articles were divided into four groups: 1) studies evaluating the mechanical properties of zirconia implants, 2) studies on osseointegration of zirconia, 3) studies on peri-implant tissue response to zirconia implant, and 4) studies on plaque accumulation with zirconia. Review of the selected articles showed that zirconia implants are reliable for placement in the jaw bone. Furthermore, zirconia implants present a material surface that is compatible with the peri-implant tissue and relatively less attractive to plaque. Based on the reviewed literature, it appears that zirconia has the potential to become the dental implant material of choice, especially for aesthetic restorations; however, some issues need to be studied further.

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This clinical report describes oral rehabilitation of a patient with sub-total maxillectomy with palatine process of maxilla and horizontal plate of palatine bone intact to retain the maxillary obturator. Clinical examination has been performed to know the amount of favorable undercuts to be used for retention of the obturator for better functional efficiency. Successful prosthetic reconstruction of hemimaxillectomy defect is a challenging procedure that requires multidisciplinary expertise to achieve acceptable functional speech and swallowing outcomes. This article describes the oral rehabilitation of a patient with sub-total maxillectomy with a maxillary obturator. Oral rehabilitation of sub-total maxillectomy patient is a challenging task. Obturation of the defect depends on volume of the defect, and positioning of remaining hard and soft tissues to be used to retain, stabilize, and support the prosthesis. A maxillary obturator for edentulous patient must provide for retention, stability, support, patient comfort, and cleanliness.

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Reconstruction of an exenterated orbit remains a challenge. Orbital prostheses are nowadays are made of silicone elastomers. A major limitation with silicone orbital prostheses is their relatively short life span. This case report describes the treatment of a patient with an exenterated orbit using a combined surgical and prosthetic approach. The upper and lower eyelids were reconstructed surgically using a deltopectoral flap. A sectional eye prosthesis was made and placed in the modified bottle-neck shaped defect to restore the patient's appearance and confidence.

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A properly fabricated provisional restoration is important in achieving a successful indirect restoration. The importance of provisional restorations as an integral part of fixed prosthodontic treatment is evident from the abundance of the literature pertaining to their importance regarding margin fidelity, function, occlusion, and esthetics. There are a variety of techniques available to suit the individual needs of the clinician and of the clinical situation, from a single unit to a complete-arch provisional fixed prostheses.