Restorative management of the worn dentition: 3. Localized posterior toothwear

In the management of localized posterior occlusal toothwear, care must be taken not only in determining whether the worn teeth are restorable, but also the desirable occlusal scheme. Assessments of the periodontal, endodontic, and coronal tooth tissues, and the occlusal relationship are necessary for a comprehensive treatment plan for worn posterior teeth.

Restorative management of the worn dentition: I. Aetiology and diagnosis

In this, the first of a four-part series on the restorative management of the worn dentition, the aetiological factors, diagnosis of toothwear and preventive measures are summarized. Later papers will deal with the management of localized anterior and posterior toothwear, the use of 'Dahl type' appliances as an effective means for the restorations and the various treatment options for the management of the dentition showing generalized wear. The series will discuss the relative merits of the treatment strategies, clinical techniques and dental materials for the restoration of health, function and aesthetics for the dentition.

Direct restoration of anterior teeth: review of the clinical technique and case presentation

Direct composite resin bonding procedures are growing in popularity as conservative and predictable restorative treatment alternatives. An understanding of the fundamental layering, contouring, and polishing principles is paramount to the success of any direct composite restoration; this awareness can be subsequently applied to indirect restorations and significantly enhance laboratory/clinician communication. This article presents a clinical technique that describes the incremental placement of direct resin veneers on a typodont and demonstrates the application of these procedures on an actual clinical case.

Effects of one versus two applications of an unfilled, all-in-one adhesive on dentine bonding

OBJECTIVES

This study examined the null hypothesis that there is no difference between the effect of a one versus two-layer applications of Prompt L-Pop (3M ESPE, Seefeld, Germany) to sound, abraded human coronal dentine.

METHODS

In group I, the mixed adhesive was applied for 15s, and light-cured for 10s. In group II, after light-curing the first layer, the adhesive was re-applied and light-cured. Specimens bonded with a hybrid composite were sectioned into beams for microtensile bond strength evaluation. Additional teeth from each group were bonded similarly using a lining composite for transmission electron microscopy examination of the resin-dentine interfaces, and nanoleakage evaluation using ammoniacal silver nitrate.

RESULTS

A significant difference (p<0.001) was detected between microtensile bond strengths in the two groups. Stained, demineralized sections revealed 3-5 microm thick hybrid layers in both groups. An electron-lucent layer between 7 and 20 microm thick was present between the adhesive and the overlying composite. This layer was absent from the interfaces after removal with ethanol before composite placement. The use of a single application in group I resulted in the direct contact of the electron-lucent layer with the dentine surface and tubular orifices. In unstained, undemineralized sections used to evaluate nanoleakage, silver deposits were found mostly in the hybrid layer in group II, but throughout the entire adhesive layer in group I.

CONCLUSION

Bonding of this unfilled all-in-one adhesive to dentine may be improved by application of a second adhesive layer after light-curing the first layer. This ensures that the exposed dentine surface and dentinal tubules are coated with adhesive that is adequately polymerized.

Management of tooth surface loss

This part of the series is devoted to tooth surface loss (TSL) not caused by caries or trauma. The management of this form of generalised TSL is included in this series because knowledge of occlusion is needed for both the diagnosis and, when indicated, treatment. There are, however, many other factors involved in the management of generalised TSL other than those associated with 'occlusion'. These will also be discussed.

[Evaluation clinical long-term curative effect and analysis of its influence factors after restoration of teeth with wedge-shaped defects]

OBJECTIVE

To evaluate the long-term curative effect clinically and analysis of its influence factors after restoration of teeth with wedge-shaped defects.

METHODS

Seventy five cases of 509 teeth with various degrees of dental wedge-shaped defects were randomly divided into two groups--the group restored by Dyract Cement and the group restored by 3M-Vitremer. Evaluation was made with the modified USPHS evaluation criterion after restoration for 1,2,4 years respectively.

RESULTS

The successful rate dropped down from 2 year successful rate 85.5% to 4-year 27.7%. The new wedge-shaped defects were presented at the cervical margin of the original restoration in 1.8% (2 years later) and 6.6% (4 years later). There were a lot of influence factors on long-term curative effect. The failure rate in the group with occlusal interference was significantly higher than that without occlusal interference.

CONCLUSIONS

The clinical successful rates are affected by the value of occlusal force on the restored teeth and the physical properties of the restorative materials. It is suggested that the process of restoration of dental wedge-shaped defect should include obviating occlusal factors as well as to improve the properties of restorative materials.

Canine risers: indications and techniques for their use

Tooth wear leads to alterations in both static and functional occlusal contacts and may contribute to temporomandibular joint disorders and dysfunction. Treatment of tooth wear may be time consuming, expensive and destructive of remaining tooth tissues. Bruxism has been associated with the recording of abnormally high clenching forces. This paper describes a technique for the provision of the canine riser restoration, which deliberately alters the cuspal incline in canine teeth to provide a canine guided occlusion. These restorations may help to control excessive loading of teeth, limit further tooth wear and assist in the management of temporomandibular disorders and dysfunction.

Clinical evaluation of two one-bottle dentin adhesives at three years

BACKGROUND

The method currently used to adhere resin to dentin involves etching, priming and bonding. Many commercial adhesives now combine priming and bonding functions in a single solution, and these are frequently called one-bottle adhesives. The purpose of this study was to compare the 36-month clinical performance of two commercial one-bottle adhesives.

METHODS

The authors enrolled 33 patients with noncarious cervical lesions in the study. A total of 101 lesions were restored with either a filled, ethanol-based adhesive (OptiBond Solo, SDS Kerr) or an unfilled, acetone-based adhesive (Prime & Bond 2.1, Dentsply Caulk) and a hybrid resin-based composite. Enamel margins were not beveled, and no mechanical retention was placed. The restorations were evaluated at baseline and six months, 18 months and 36 months after placement using modified Cvar/Ryge criteria.

RESULTS

The retention rates at 36 months were 93.3 percent for the ethanol-based adhesive and 89.4 percent for the acetone-based adhesive. The difference in retention rates was not statistically significant. In both groups, 12 percent of the retained restorations had marginal staining, but no recurrent caries was detected around any restoration. Other restoration characteristics such as marginal adaptation and color match remained excellent three years after placement.

CONCLUSIONS

The performance of both adhesives was excellent during this 36-month clinical trial. At the most recent recall evaluation (that is, 36 months), the filled, ethanol-based adhesive exhibited slightly better bond durability, but the difference between the two materials was not statistically significant.

CLINICAL IMPLICATIONS

The one-bottle adhesives evaluated in this study provided excellent clinical retention of Class V restorations without mechanical retention. When the materials are used properly, restorations are retained at a high rate during at least three years of clinical service.

Occlusal disease revisited: Part II

In part I of this article, the evolution of bruxism from childhood was discussed. Further, the different types of anterior tooth wear were reviewed. Specifically, the type of wear noted in bruxed-braced or cross-over position was pointed out. Examples were illustrated to allow the practitioner to recognize the type of parafunction in advance of treatment. This article will continue the discussion of cross over with moderate to extreme examples. Suggestions for treatment are discussed depending on the severity of the problem. Restorative failure and the implications for implant dentistry are noted.

A question of space: options for the restorative management of worn teeth

The prevalence of tooth surface loss has increased in recent years. The essence of management is an effective preventive regime; however, in many instances restoration may also be necessary. A number of strategies is available for creating sufficient space to enable restoration and several techniques for restoration known. This article reviews the significance of the vertical dimension of occlusion and describes the restorative management of a patient affected by severe tooth wear.

Presentation, diagnosis and initial management of patients referred to a hospital tooth wear clinic

Information on presenting complaints, diagnosis and initial management strategy was recorded on a proforma for 114 consecutive patients referred to a hospital tooth wear clinic over a two-year period. Over twice as many male patients were referred as females. Twenty percent of patients had no presenting complaint and the others shared the common complaints concerning appearance, sensitivity and their deteriorating dentitions. The assessment of aetiology identified attrition as the most common cause of tooth wear in the subject group studied. About half the group were prescribed preventative treatment only and the other half were deemed to require restorative dental treatment.

Orthodontic-restorative treatment of chipped or worn incisors

PURPOSE

To evaluate the shear bond strength of esthetic adhesive restorations for worn or fractured incisal edges.

MATERIALS AND METHODS

On 30 human extracted incisors the edge was reduced and a bevel was prepared in the thickness of enamel. Then, the incisal edges were restored, using a different adhesive system in each of the three groups to which the sample teeth had been randomly assigned. Group A: Scotchbond Multi-Purpose Plus, in combination with phosphoric acid, and Z100 as a restorative material. Group B: Scotchbond 1 after etching with phosphoric acid, plus Z100. Group C: F2000, a compomer, in combination with its Primer/Adhesive. The differences in the bond strength values among the three groups were tested for statistical significance. Also, the resistance to load of the restored teeth was compared with that of 10 intact incisors (Group D) (controls). A statistical analysis was performed to test the significance of the differences.

RESULTS

No statistically significant difference in shear bond strength was found between Scotchbond Multi-Purpose Plus (17.6 MPa) and Scotchbond 1 (14.8 MPa), whereas F2000 gave significantly lower bond strength values (10.1 MPa). As compared with intact incisors, the teeth restored with either Scotchbond Multi-Purpose Plus or Scotchbond 1 did not perform significantly differently under load. On the other hand, the incisors restored with F2000 gave, as compared with the controls, a resistance to loads significantly lower and of a questionable reliability from a clinical standpoint. SEM observations performed on some of the samples revealed that when phosphoric acid was used to condition the substrate, a deep and uniform demineralization of the enamel was effected, and a mechanically retentive interlocking was created at the interface between resin and enamel. The Adhesive/Primer of F2000 was unable to produce an equally retentive morphology.

Two-year clinical performance of a polyacid-modified resin composite and a resin-modified glass-ionomer restorative material

This study compared the clinical performance of a polyacid-modified resin composite and a resin-modified glass-ionomer restorative material over two years. Thirty-four pairs of restorations of Compoglass and Fuji II LC were placed in caries-free cervical erosion/abfraction lesions without tooth preparation. Restorations were clinically evaluated at baseline, 6, 12, 18 and 24 months using modified Ryge/USPHS criteria. A significantly higher incidence of failed restorations was found with the polyacid-modified resin composite (p < 0.05).

Eighteen-month clinical evaluation of a filled and unfilled dentin adhesive

OBJECTIVE

The purpose of this study was to evaluate the performance of a filled (OptiBond Solo) and an unfilled (Prime & Bond 2.1) "one-bottle" adhesive in Class V restorations after 18 months of clinical service.

METHODS

Thirty-three patients with non-carious cervical lesions were enrolled in the study. A total of 101 lesions were restored using one of the adhesives and a hybrid composite resin. Enamel was not beveled, nor was any mechanical retention placed. The restorations were evaluated at baseline, and at 6 and 18 months after placement using modified USPHS criteria.

RESULTS

Cumulative 18-month retention rates were 93.6% for OptiBond Solo and 98.0% for Prime & Bond 2.1. The difference in retention rates was not statistically significant. For OptiBond Solo, the only notable problems were interfacial staining and marginal adaptation, both of which were less than ideal in 9% of restorations. Marginal problems were slightly less frequent for Prime & Bond 2.1 restorations, but the difference was not significant.

CONCLUSIONS

Both adhesives provided Class V retention rates exceeding the 18-month, full acceptance guidelines set by the American Dental Association. Any additional benefit provided by the use of a filled adhesive was not detected in this 18-month clinical trial.

Cervical compomer restorations: the role of cavity etching in a 48-month clinical evaluation

Compomers are defined as polyacid-modified resin composites. They are supposed to combine the advantages of traditional glass-ionomer cements with resin composites. This study clinically evaluated a compomer in cervical cavities. Sixty cervical cavities in premolars and molars (24 with cervical caries and 36 with abrasions) randomly divided into two groups of 30 teeth (Group 1 and Group 2) were restored with Dyract (DeTrey-Dentsply, York, PA 17405-0872). The cavities of Group 2 were etched for 30 seconds with orthophosphoric acid before compomer application, while the Group 1 cavities received no treatment. All the restorations were evaluated every six months, up to 48 months: characteristics assessed according to USPHS-modified standards were retention, secondary caries, post-operative sensitivity, marginal adaptation and discoloration, color and wear. The Kaplan-Meier's survival analysis was performed. In both groups, retention was high without any statistically significant difference. No difference was found between the two groups for caries, post-operative sensitivity and wear--that all had a low incidence. Color was not perfectly matched, however, there was no statistically significant difference between the two groups. Marginal discoloration and marginal adaptation loss were significantly higher in non-etched group (p < 0.05). Clinically relevant failure required 17.2% of restorations in the non-etched group and 10% in the etched group to be replaced: this difference was not statistically significant. Dyract has an acceptable clinical behavior when used in cervical cavities. Its marginal adaptation is enhanced by etching.

Restoring esthetics and anterior guidance in worn anterior teeth. A conservative multidisciplinary approach

BACKGROUND

Developments in adhesive dentistry have given the dental profession new restorative materials and technology to restore esthetics and function to the worn anterior dentition. This article illustrates, through a clinical case study, the clinical requirements for restoring esthetic harmony and functional stability to the worn anterior dentition.

CASE DESCRIPTION

The author presents the case of a 24-year-old man who sought esthetic dental treatment because he was unhappy with the appearance of his maxillary anterior teeth. The review of his dental history revealed that he ground his teeth at night. The author performed a complete evaluation of the causes of the patient's bruxism and created a diagnostic preview to, among other things, develop the relationship between the condylar and anterior guidance and to establish the esthetic requirements for the final restorations. Treatment included periodontal recontouring, tooth preparation and placement of temporary and then permanent restorations; the patient also was given an occlusal guard to protect the restorations against future bruxing.

CLINICAL IMPLICATIONS

Whatever the cause of occlusal instability, it is important that the restorative dentist be able to recognize its signs--such as tooth hypermobility, tooth wear, periodontal breakdown, occlusal dimpling, stress fractures, exostosis, muscle enlargement and loss of posterior disclusion. When restoring the worn dentition, the clinician should bear in mind the five P's: proper planning prevents poor performance.

Clinical evaluation of allografts and homografts for restoration of missing tooth structure

STATEMENT OF PROBLEM

The clinical performance of bonding human tooth fragments to either replace missing teeth or to restore defective teeth is unclear. Prospective studies can help to predict the success of such treatment options.

PURPOSE

This study evaluated the feasibility of bonding tooth tissue homografts and allografts either to replace missing teeth or to restore defective teeth, and estimated the success rate of bonded allograft and homograft restorations 3 years after placement.

METHOD AND MATERIAL

Twenty clinical cases were treated by bonding tooth fragments or crowns into 6 groups (Gp): Gp1, cervical erosion and abrasion lesions (6); Gp2, incisal edge fractures (4); Gp3, partially destroyed crowns (4); Gp4, teeth placed in a removable prosthesis (2); Gp5, missing tooth with no opposing tooth (2); and Gp6, temporary space maintenance (2). Restorations were examined using USPHS criteria every 2 months and whenever a patient called to report a failure.

RESULTS

After a 3-year follow-up, the overall success rate was 80% for the 20 restorations. The 95% confidence interval was 63% to 94%. Four restorations failed by debonding (Gp2 [2]; Gp5 [1]; Gp6 [1]) during the first 4 months. The main cause of failure appeared to be excessive occlusal loading.

CONCLUSION

Within the limitations of this clinical study, the results after a 3-year follow-up showed the success rate was not less than 63% for bonded allograft and homograft restorations.

Clinical evaluation of EBS dentine bonding agent: one year results

There are numerous dentine bonding agents currently on the market, the majority of which adhere by means of infiltration of a hydrophilic polymerizable diacrylate into dentinal collagen exposed by acid treatment. The purpose of the present study was to evaluate the clinical performance of one such product, EBS dentine bonding, in non-undercut caries-free cervical lesions. Forty cavities were restored in eight patients of mean age 53 years. The manufacturer's instructions were followed, which involved essentially etching the enamel and dentine for 20 seconds with 32 per cent phosphoric acid, application and evaporation of EBS Primer, followed by placement and curing of EBS Bond, and restoring the cavity with Pertac II (ESPE) hybrid resin composite. Restorations were photographed at base line and one year for evaluation of marginal discolouration on a continuous linear rating scale. At six months, one patient with four restorations was not available; the remaining 36 restorations were all present. At one year, one restoration was missing, giving a cumulative retention rate of over 97 per cent. One of the 36 restorations exhibited very mild marginal discolouration.

Investigation and treatment of patients with teeth affected by tooth substance loss: a review

Tooth substance loss, an increasing problem, may result from erosion, abrasion and attrition, often with more than one of these acting together. Investigation requires a detailed history and examination. The aim of treatment may be prevention of further damage in less affected cases. The treatment of severe tooth substance loss may be complex, especially in view of the reduced amounts of tooth substance which may be available and the need to find space because of the compensatory over-eruption of worn teeth.

Utilization of a small-particle composite resin for anterior and posterior restorations

The ability to acid etch enamel has resulted in the proliferation of adhesive dental techniques that enable conservation of sound tooth structure during the preparation and restorative phases. Recent research has focused on the clinical procedures that use composite resins as well as the material formulations involved in adhesive treatment. This article discusses the physical and optical properties of a composite resin with a smaller filler particle and demonstrates its utilization in anterior and posterior applications as a means of providing functional aesthetic dental care.