The use of incinerated pig head in dental identification simulation

PURPOSE

The aim of this exercise was to simulate a disaster victim identification scenario to allow training in documentation of postmortem incinerated remains and reconciliation of dental data.

METHOD

Varying number of restorations were placed in ten pig heads. The teeth and restorations were charted, with the restorations radiographed and documented, creating an ante-mortem data set. The following day the heads were cremated. Following cooling and recording they were transported for a post-mortem examination by trained specialist odontologists who were not involved in the initial antemortem phase. Recordings included the charting of teeth, restorations, lost teeth, and radiographs to simulate a post-mortem examination. A reconciliation of postmortem to antemortem information was attempted.

RESULTS

There was an unacceptable amount of error in the postmortem examination of the heads. The errors related mainly to avulsed teeth and incorrect opinion of which charted surfaces the restorations were placed upon. Also noted were a considerable number of root fractures occurring beneath the crestal bone. This observation does not mimic the evidence observed in human incinerated teeth where the crowns tend to fracture off the roots at the dentin-enamel junction.

CONCLUSION

The use of incinerated pig (Sus Scrofa) heads is not an ideal model for forensic odontology training in disaster victim identification. Differences in both anatomy and behavior following exposure to heat were shown to hamper documentation and subsequent comparison to antemortem data.

CAD/CAM-based polymer provisionals as treatment adjuncts

The role and function of provisional restorations has changed significantly in recent years. The reasons include the improvement of material properties and the CAD/CAM production option using polymer blanks, which are offered by various manufacturers. Besides their classic indications in crown and bridge prosthodontics, provisional restorations are now used for soft-tissue management, preparation and adaptation in complex restorations that include changes in vertical relations, and as mock-ups in esthetic dentistry.

Biomechanical behavior of restored and unrestored mandible with shortened dental arch under vertical loading condition

The aim of this in vitro study was to investigate the strain distribution of the compressed mandible bone under the applied restoration- removable partial denture and to compare with the same but unrestored mandible under vertical (occlusal) load and to find out whether removable partial denture-restored or unrestored mandible causes greater strain effect on supporting tissue. Four mandible models were tested during loading for the purpose of strain measuring. Digital image correlation system (GOM - German Optical Measuring, Braunschweig, Germany), used for measuring strain consists of two digital cameras and software ARAMIS (6.2.0, Braunschweig, Germany). Remaining teeth suffer from greater strain in the mandible model without removable partial denture (7.5-10%). On the contrary, mandible with removable partial denture shows the maximum strain below the denture saddle (3.5%). However, it can be noticed that the marginal bone of the second lower praemolar in both experimental models is deformed whether the mandible model has (2.8%) or has not (10%) replacement. Within the limitations of this study the higher strain is observed in mandible model without replacement and the strain is limited locally, in the bone region that surrounds remaining teeth and mental foramen.

Effect of implant abutment modification on the extrusion of excess cement at the crown-abutment margin for cement-retained implant restorations

PURPOSE

To compare the effect of implant abutment modification on the amount of cement extruded at the crown-abutment margin and to evaluate the vertical discrepancy after cementation.

MATERIALS AND METHODS

Access openings of titanium abutments were modified with an opening (open) and placement of two vent holes 3 mm from the occlusal edge and 180 degrees apart (internal vent). Access openings were filled with resin material (closed) and used as controls. Each abutment was secured to an implant analog. Eugenol-free zinc oxide cement (TempBond NE) was selected to cement the cast crowns (n = 9) onto test abutments. The amount of cement extruded out of the margin was calculated, and vertical seating discrepancies were determined with a linear transducer device before and after cementation. Differences among groups were analyzed statistically.

RESULTS

The mean amount of extruded cement ranged from 36% to 90% of the total cement placed within the crowns. The order, from least to greatest amount of excess cement extrusion at the margins, was internal vent, open, and closed; significant differences were observed between test groups. The net vertical discrepancies of tested specimens ranged from -7 μm to +6 μm (mean, 0 μm). No statistically significant differences in vertical discrepancy were found between the groups.

CONCLUSIONS

Venting the hollow abutment resulted in the least amount of cement extrusion when compared to closing off the screw access channel or leaving it open. Within the limitations of this study, it may be concluded that the use of two, 0.75-mm radius vent holes placed 3 mm apical to the occlusal area of the abutment and 180 degrees apart will limit the amount of cement extruded into the gingival sulcus of implant-retained crowns.

Immediate restoration with ti-unite implants: practice-based evidence compared with animal study outcomes

PURPOSE

Clinicians often do not have the benefit of adequate safety or clinical data when evaluating the merit of either newly marketed implant devices or novel clinical procedures. This has been the case for dental implants following the initial documentation of their safety and efficacy and is demonstrated in the evolution of immediate load application. Following demonstration of safety and successful application of an implant in an animal study prior to its market release, this report provides the clinical outcomes for the first 100 Ti-Unite implants provided to 24 patients in a clinical practice over 9 years.

MATERIALS AND METHODS

An electronic record/clinical database review of consecutive early loaded implants from a multiple surgeon/single prosthodontist practice was conducted for quality assurance. Data extraction of standard exposure and outcome variables was accomplished by a trained individual not affiliated with the clinical practice.

RESULTS

The results revealed one failure before and none following definitive restoration with a variety of prostheses. The mean length of time from immediate to definitive restorations was 5.3 ± 1.1 months for crowns, 3.9 ± 1.3 months for fixed partial dentures, and 7.8 ± 4.1 months for mandibular "hybrid" prostheses. The most common unexpected findings during the initial three postinsertion visits were lost access restoration and cement failure.

CONCLUSIONS

Pre-market animal data regarding the safety and success of a new implant used with an early loading protocol was replicated in the clinical results of the first 100 implants used in practice. Additionally, the clinical results are favorable when compared to conventional loading protocols from this same practice and provide helpful comparative metrics (delayed vs immediate loading) to use when discussing implant treatment with patients.

Enhancing restorative, periodontal, and esthetic outcomes through orthodontic extrusion

Traumatic tooth fractures, dental caries, and overzealous tooth preparations can lead to the loss of coronal tooth structure, thus complicating the definitive prosthetic plan. Although exposure of additional clinical tooth structure by surgical crown lengthening is often recommended, such an approach is usually discouraged because of the possible adverse periodontal changes to the adjacent teeth and compromised esthetics, especially in the presence of an otherwise intact arch. This article discusses the application of orthodontic extrusion to conservatively restore a single tooth with minimal coronal tooth structure in the esthetic zone. A detailed description of the prosthetic approach used before, during, and after orthodontic therapy is presented.

Indications for Splinting Implant Restorations

PURPOSE

The purpose of this article was to review the literature concerning the need to splint implants together when restoring them with a provisional restoration immediately after implant placement.

METHODS

The literature is reviewed concerning the rationale for splinting teeth and reports concerning the efficacy of splinting implants together. Based on this team's experience with a prospective series of consecutive 2 to 5 unit provisionalization cases, guidelines are included with case examples for understanding the technique.

CONCLUSION

As long as canine guidance is present, and occlusion is stable, multiunit single quadrant restorations do not need to be splinted when provisionalized.

Chairside Preparation of Provisional Restorations

PURPOSE

Increasing demands are placed on the oral and maxillofacial surgeon to perform early or immediate loading of dental implants due to demands and expectations of the referring doctor and patients. In order to provide the patient with an immediately loaded, functioning implant, the surgeon should consider incorporating the fabrication of the temporary restoration as an additional service for their implant patients.

MATERIALS AND METHODS

The armamentarium necessary for the oral and maxillofacial surgeon to deliver a temporary restoration will be described. The materials and components needed to provide this service will be listed and a sequence of steps to easily accomplish the fabrication of a temporary crown will be presented.

RESULTS

Temporary crowns cemented onto temporary or permanent implant abutments are ideal for the management of gingival contours. Initial soft tissue healing around the contours of the temporary crown, even with minimally invasive techniques, provides many advantages for the patient. There is less likelihood of gingival scarring, which minimizes the incidence of gingival recession and the patient is restored to normal form and function immediately.

CONCLUSIONS

The fabrication of the temporary prosthesis by the oral and maxillofacial surgeon provides benefits for the surgeon, restorative doctor, as well as, the patient. By working closely with his or her restorative colleagues, the surgeon will be able to provide his or her implant patients with immediate return to form and function intraorally with minimum effort.

Use of an Immediate Provisional Implant to Support a Full-Arch Interim Restoration: A Clinical Report

The use of provisional implants as the sole or adjunct mean of stabilization for interim fixed partial dentures has gained popularity in implant prosthodontic treatment. These implants can be used between submerged implants during the healing phase to provide support for interim fixed or removable partial dentures. In this clinical report, a provisional implant used to provide support for a full-arch fixed interim restoration is described. Positioned between adjacent conventional implants, the provisional implant was placed during the same surgical procedure. As a result, an immediate acrylic fixed partial denture supported by natural teeth and the provisional implant provided a comfortable and esthetic interim restoration during the osseointegration period.

Diagnostic and technical approach to esthetic rehabilitations

The success of an esthetic rehabilitation depends on the understanding of the patient's needs and on effective communication among the entire dental team. The involvement of the dental technician since the beginning of the treatment plan is one of the keys for success. This article describes a systematic approach to oral rehabilitations involving esthetic areas. Technical suggestions for the construction of the diagnostic wax-up, the provisional, and the final ceramic restorations are illustrated in a logical sequence.

Laboratory-processed acrylic resin provisional restoration with cast metal substructure for immediately loaded implants

Most methods of immediate loading of implants reported in the literature involve retrofitting a pre-existing denture to the implants. This article describes and illustrates clinical and laboratory procedures for immediate loading of implants in the edentulous mandible with the use of a laboratory-processed, provisional, screw-retained, implant-supported fixed complete denture that incorporates a cast metal reinforcement.

A Prospective Randomized Study Comparing Two Different Degrees of Mandibular Advancement with a Dental Appliance in Treatment of Severe Obstructive Sleep Apnea

The objective of this study was to compare the effect of two different degrees of mandibular advancement (MA), 75% versus 50%, on somnographic variables after 6 months of dental appliance treatment in patients with severe obstructive sleep apnea (OSA). A further purpose was to compare the number of adverse events on the stomatognathic system and the effects of dental appliance treatment on the presence of daytime sleepiness. Eighty-six males with severe OSA (apnea index > or = 20) were randomly allocated to either 75% or 50% MA. Forty patients in the 75% MA group and 37 patients in the 50% MA group completed the 6-month follow-up. The effectiveness of treatment in terms of normalization (apnea index < 5 and apnea/hypopnea index < 10) with 75% MA was 52%, which was significantly higher (p = 0.04) than the 31% achieved with 50% MA. The dental appliance had few adverse events on the stomatognathic system regardless of group, and the number of adverse events did not differ between the two groups. Finally, the mean value of Epworth Sleepiness Scale scores decreased significantly from 11.6 at baseline to 8.0 at follow-up (p < 0.001). No significant difference was observed between the two groups. The results indicate that a dental appliance could be an alternative treatment for some patients with severe OSA.

Composite indirect-direct method for fabricating multiple-unit provisional restorations

This article describes a method for fabricating multiple-unit provisional restorations by use of the indirect-direct method without the need for abutment preparation on diagnostic casts. Composite is used with fiber reinforcement to create a provisional shell in a vinyl polysiloxane matrix. This method reduces chair time, as well as laboratory time required to fabricate provisional restorations. Control of restoration contours and incisal edge position is also enhanced.

Dahl appliances used for the restorative management of localized anterior tooth erosion

Dahl partial bite-raising appliances have been used over the past 30 years for the management of occlusal tooth tissue loss, particularly in patients who have lost normal occlusal vertical dimension. The more recent use of Dahl-type appliances for individual teeth has changed the restorative management of patients with localized anterior tooth erosion. The Dahl treatment principle can be applied to those patients with and without the loss of occlusal vertical dimension. Palatal bite-raising platforms can be used to re-establish anterior tooth guidance for disocclusion of the posterior teeth without occlusal interferences. The treatment principle is illustrated with clinical cases.

The quality of clinical fit of stainless steel bands used in endodontics

Stainless steel bands are commonly advocated to protect posterior teeth against fracture during endodontic treatment and before final restoration. A poorly fitting band, however, may lead to a compromised coronal seal and gingival irritation. This radiographic study assessed the quality of fit and marginal adaptation in the proximal area of stainless steel bands placed during routine endodontic treatment. Clinical radiographs of 120 maxillary and mandibular premolars and molars were evaluated. All radiographs were taken during routine clinical endodontic treatment and randomly selected from cases completed by ten operators. Approximately one-half of cases did not meet the criteria of adequate marginal seal (mesial: 65/120; distal: 49/120). Only 11 teeth were found to have adequate fit of the band on both mesial and distal aspects of the tooth. The most common reason for inadequacy of fit was lack of band adaptation to the tooth contour in the cervical region. Stainless steel bands have a high possibility of poor marginal fit and should be used with the awareness that they may produce other clinical problems.

Influence of different transitional restorations on the fracture resistance of premolar teeth

Controversy exists over the most favorable material and type of restoration to be used to transitionally restore teeth destined to be crowned. This in vitro study uses fracture resistance testing to compare eight different transitional restorations in maxillary premolars. Ninety sound maxillary premolars were randomly selected and allocated to nine groups, each comprising 10 teeth. One group remained unrestored and was used as the control. Teeth in the remaining groups were prepared to a standard cavity form using: a copy milling process removing the palatal cusp. Restorations were placed using amalgam with dentin pins and cavity varnish; amalgam with an amalgam bonding agent; resin composite with dentin pins and a dentin bonding agent; resin composite with a dentin bonding agent only; resin-modified glass ionomer with dentin pins; resin-modified glass ionomer cement alone and cermet with dentin pins and cermet alone. Each restored tooth was then subjected to axial loading via a bar contacting the buccal and restored palatal cusps until failure of the restored tooth occurred. The mean load-to-fracture values were statistically compared and the modes of failure recorded. It was found that the choice of restorative material and type of restoration had little effect on the fracture resistance of the restored tooth with the exception of those teeth restored with reinforced glass ionomer cement alone, which exhibited a significantly lower resistance to fracture than the other restored teeth. However, the choice of restorative material/technique did influence the mode of failure. Failure in teeth restored with resin-modified glass ionomer cement alone produced the least damage to the remaining tooth tissue when failure occurred. Consequently, this material may offer the most favorable range of properties for the transitional restoration of extensively broken-down maxillary premolar teeth destined to be crowned. Furthermore, the findings of this study fail to support the use of dentin pins in the placement of bonded build-up restorations.

[Clinical observation of oral appliances in the treatment of obstructive sleep apnea syndrome]

OBJECTIVE

To explore the effect of treatment with the oral appliances on 36 cases with obstructive sleep apnea syndrome (OSAS).

METHODS

The patients are requested to put on the proper oral appliances when sleeping. Polysomnography (PSG) are used to measure the apnea hypoventilation index(AHI), lowest SaO2 and longest apnea time before and after treatment.

RESULTS

Having been Compared with the obtained data, the AHI decreased, the lowest SaO2 increased and the longest apnea duration shortened significantly (P < 0.05) in OSAS patients after oral appliance treatment.

CONCLUSIONS

The oral appliances helped to widen the upper airway, stabilized the lower jaw bone on a forward position to make the tongue and the soft palate move forward, increased the effective amount of inhaled air while sleeping and improved sleeping quality. There fore, it is an effective method for the treatment of OSAS.

[In vitro comparison of marginal adaptation of different filling materials. II. Effect of the site and method of preparation on the marginal adaptation]

In a two-month in vitro experiment we examined the marginal adaptation of ten dental materials. Fifty Class II restorations were prepared extending to the cemento-enamel junction. The cavities of the composite restorations were bevelled at the vestibulo-occlusal and -approximal enamel margins, on the other side enamel and gingival margins were prepared conventionally. The specimens were thermocycled and examined with SEM. The microleakage was measured at the vestibulo-occlusal and -approximal tooth-filling junction, where adhesive technique was used, and at the gingival, oroocclusal and -approximal margins, which were not bevelled before. The obviously most important conclusion of the study is, that in the case of deep Class II cavities the amalgam has a better adaptation at the gingival margin than the examined composite resins.

A new and indirect working die technique for fabricating temporary restorations

A time- and labor-saving indirect method for fabricating temporary restorations that features removable dies (coined the indirect working die technique), is introduced and described. It takes advantage of the accuracy of the traditional indirect method, as substantiated in the literature, but employs new methods and uses materials in a novel way.

The use of an orthodontic thermoplastic retainer as a provisional anterior restoration: a case report

Children who present with extensive fractures of anterior teeth pose a difficult clinical problem. Pulpal and periodontal injuries must be carefully assessed and managed. Rapid restoration of the form and contour of the extensively fractured tooth is advisable, not only to improve esthetics but also to prevent unwanted tipping or tilting of adjacent teeth and overeruption of opposing teeth. A modified Essix retainer, simply constructed in the laboratory, can be used to provisionally restore the extensively fractured anterior tooth.

Fabrication of acrylic resin copings for CeraOne provisional restorations

A technique is described for fabricating autopolymerizing acrylic resin copings for CeraOne provisional restorations. This method has the advantage of providing a chemical bond rather than only a bond between the mechanical coping and the relined provisional crown, as is the case when using the provisional components supplied by the manufacturer. The technique describes provisionalization at the time of stage II surgery. This type of coping can also be used after a period of soft tissue healing when a healing abutment is employed. The benefits of the procedure include increased patient satisfaction and reduced chair time for repairs.

The template-VLC provisional restoration system

The removal of tooth structure during preparation results in varying degrees of pulpal hyperemia. The ability of the pulpal tissue to respond either by recovery or degeneration depends in part upon the adequacy and fit of the provisional restoration. The response of the gingival tissue also depends on a large degree on the success of the temporary coverage. Provisional restorations are commonly given less attention and importance thereby biologic, mechanical, and esthetic considerations are not adequately met. Since a provisional restoration must be made or improvised during the same appointment in which the abutment teeth are prepared, costly chairside time most often leads to an unacceptable restoration. Failures such as color instability, color incompatibility, inappropriate anatomic contours, fractures, occlusal disharmony, changes in tooth position, gingival inflammation, and unhealthy periodontal conditions are usually encountered. A technique of fabricating an exacting provisional restoration with compliance to optimum quality is presented.

Provipont & Provilink. Maximizing aesthetics and function when fabricating provisional restorations

Only a few decades ago, the use and fabrication of provisional restorations was still a neglected area of restorative dentistry. Recently, a new recognition has been given to the importance of provisional restoration--maintenance of space for the tooth being, restored, acceptable interim aesthetics, cover against bacterial infiltration, and the registration of vital information for the fabrication of final restorations. This two-part article presents the clinical procedures for the utilization of provisional restorations in the anterior area and in inlay/onlay preparations.

A safe technique for removal of provisionally cemented crowns

A technique is presented for removing full-cast crowns and porcelain crowns that have been temporarily or provisionally cemented. A rubber dam retainer clamp with rubber dam attached is placed on the crown and clamped near its margins. Steiglitz forceps are used to apply pressure and leverage. The assembled unit is removed with the Steiglitz and safely removes the loosened crown from the mouth.