Do composite resin restorations protect cracked teeth? An in-vitro study.

Aims: To evaluate whether bonded resin composite restorations can effectively immobilise the tooth segments in teeth with a synthesised crack under loading, by exploring the impact of the restoration type (direct versus indirect composite resin) and restoration design (inlay versus onlay) on the fatigue resistance. Methods: Sound human third molars underwent large mesio-occluso-distal preparations and a groove was cut to simulate a crack. Standardised procedures were adopted and measures were taken during teeth selection so that systematic error and methodology bias were minimised. The teeth were randomly assigned to four groups. The specimens were submitted to cyclic loading and loaded until fracture or to a maximum of 185,000 cycles. The failure mode was recorded. Results: No failure was observed in 'direct' groups up to the 1000 N force. Survival analysis revealed statistically significant higher survival rates for 'direct' groups compared to 'indirect' groups (χ2 = 11.352, df = 1, p = 0.001) while there was no significant difference between 'inlay' and 'onlay' groups (χ2 = 0.015, df = 1, p = 0.901) (pooled data). Conclusions: Within the limitations of this in-vitro study, it can be concluded that the direct composite resin restorations sufficiently protected the cracked teeth regardless of the cavity design. As there was no statistically significant difference in survival rates between inlays and onlays it is not possible to favour one design type over the other.

Evaluation of marginal leakage after mechanical fatigue cycling of composite inlays luted with different cements.

This in vitro study evaluated the marginal microleakage of composite inlays luted with 3 different cement systems. The null hypothesis was that the luting materials would not influence dye penetration, showing the same degree of microleakage. Thirty-six sound molars were selected, mesio-occlusodistal cavities were prepared, and the teeth were randomly divided into 3 groups (n = 12). Composite resin inlay restorations were made and cemented using a dual-curing resin cement (Calibra), a light-curing flowable composite (Charisma Flow), or a self-adhesive resin cement (RelyX Unicem). The restored teeth were subjected to fatigue cycles and immersed in 0.5% basic fuchsin dye for 24 hours. Two orthogonal cuts were made to enable evaluation of dye penetration at the cervical and occlusal margins. The sections were evaluated with a 4-point scale ranging from 0 (no penetration) to 3 (penetration up to the cavity floor [occlusal margins] or axial wall [cervical margins]). The Calibra and Charisma Flow groups showed greater microleakage, notably at the cervical margins, whereas RelyX Unicem specimens showed the least dye penetration. Significant differences were found between the Calibra and Charisma Flow groups and between the Charisma Flow and RelyX Unicem groups (P < 0.05). No statistically significant differences were detected between the Calibra and RelyX Unicem groups. The microleakage associated with the flowable composite was significantly greater than that associated with both resin cements, results that discourage its use for luting of Class II composite inlays.

A retrospective clinical study on the longevity of posterior Class II cast gold inlays/onlays.

OBJECTIVE: To investigate the longevity and reasons for failure of posterior cast Class II gold inlays and onlays among a group of Norwegian adults. The term inlay was used for both inlays and onlays. METHODS: A cohort of 138 patients regularly attending a general practice for check-up were examined in 2016. The patients had a total of 391 posterior gold inlays placed in the period 1970-2015. The inlays were categorized as successful, repaired or failed. Reasons for failure were classified as either "secondary caries", "fractures", "lost inlay" or "other". Participation was voluntary and no compensation was given. RESULTS: The mean age of the patients at placement was 50.8 years (SD: 12.7 yr). Most gold inlays were placed in molars (85.9%) and 14.1% in premolars; 49.4% of the inlays were in the maxilla and the 50.6% in the mandibula. Average length of follow-up was 11.6 years (range: 1-46 years, SD: 7.9); 82.9% were classified as successful, 10.7% as repaired and 6.4% as failed. Reasons for failure were secondary caries (41.3%), lost inlay (25.4%), fractures (23.8%) and other (9.5%). Mean annual failure rate (AFR) was 1.69% for repaired and failed inlays combined. However, if repaired inlays were considered as success, the AFR decreased to 0.57%. Multi-level Cox regression analyses identified low age of the patient and high number of restored surfaces as risk factors for failure. CONCLUSION: The present retrospective clinical study demonstrated an acceptable annual failure rate for Class II cast gold inlays.

Sudden Onset of Subcutaneous Air Emphysema After the Application of Air to a Maxillary Premolar Located in a Nonsurgical Field.

Although rare, subcutaneous air emphysema can occur during dental procedures such as endodontic treatment, surgical extractions, and preparing a tooth for an indirect or direct dental restoration. We report the development of a subcutaneous air emphysema that was introduced through the periodontal ligament of an untreated premolar after the use of an air syringe to dry the tooth.

A systematic review of the survival and complication rates of inlay-retained fixed dental prostheses.

OBJECTIVES: The aim of this systematic review was to investigate the survival and complication rates of inlay-retainer fixed dental prostheses (IRFDPs). DATA/SOURCES: A systematic search was conducted in the PubMed, EMBASE, and Cochrane Library databases in English and time filters (articles published from 1960) were used. STUDY SELECTION: Randomized controlled trails (RCTs), controlled clinical trials (CCTs) and prospective cohort studies on IRFDPs with a mean follow-up period of at least 2 years were included. Among 501 screened articles, one RCT and ten prospective cohort studies were included in this study. Of the included studies, information on failure and complications was independently extracted by two reviewers in duplicate. The failure and complication rates of IRFDPs were pooled with a random effect model and Poisson regression was applied to further investigate the influence of framework materials. The estimated 3- and 5-year survival rates of IRFDPs were 92.6% (95% CI: 85.8-97.6%) and 87.9% (95% CI: 77.4-96.1%), respectively. Debonding, fracture, dentine hypersensitivity and secondary caries were primary complications. The estimated 5-year rates of debonding, veneer fracture and secondary caries were 5.3%, 15.2% and 2.7%, respectively. Additionally, fiber-reinforced composite IRFDPs exhibited a lower incidence of debonding and caries with a higher rate of veneer fracture compared with metal-based and all-ceramic IRFDPs (p<0.05). CONCLUSIONS: Compared with conventional fixed dental prostheses (FDPs) and implant-supported single crowns (ISCs), IRFDPs exhibited an acceptable 3-year survival rate but higher complication rates of debonding and veneer fracture. CLINICAL SIGNIFICANCE: IRFDPs can be recommended as viable short- or middle-term minimally invasive alternatives to short-span conventional FDPs and ISCs, while the clinical outcome of IRFDPs as long-term definitive restorations still calls for further research. The indications of IRFDPs should be strictly controlled and monitored.

Use of Locking Plate and Strut Onlay Allografts for Periprosthetic Fracture Around Well-Fixed Femoral Components.

BACKGROUND: The purpose of this study was to determine: validated clinical and radiographic outcomes of periprosthetic femoral fractures around stable hip implants treated with plate fixation and additional cortical strut onlay allografts without revision of the stem; radiographic signs of fracture healing; allograft-to-host bone union; resorption of cortical strut allograft; and frequency of complications. METHODS: At our institute, 24 patients (25 hips) were identified with Vancouver type B1 fracture at the tip of the femoral stem and one patient (one hip) was identified with a Vancouver type C fracture of the femur. All these fractures were treated with combined use of locking plate fixation and cortical strut onlay allografts. There were 18 women and 7 men, with an average age of 63 years. Harris hip score and University of California, Los Angeles activity score were used to assess postoperative function. The average duration of follow-up was 3.7 years (range, 1-7 years). RESULTS: Harris hip score at final review was 86 points (range, 65-95 points). University of California, Los Angele activity score averaged 5.8 ± 1.3 point (range, 3.5-10 points) at final follow-up. All but 2 patients returned to their preoperative functional level within 1 year. Twenty-three of 26 hips had fracture union following the first operation. Three hips were failed to obtain fixation because of insufficient length of plate and allograft. Cortical strut onlay allografts were incorporated in the host femur in all hips by one year. Minor resorption of allograft was noticed, but there was no failure of any of the cortical strut allografts. CONCLUSION: The cortical strut onlay allografts facilitated the mechanical stability and the biological fracture healing in addition to plate fixation.

Efficacy of composite versus ceramic inlays and onlays: study protocol for the CECOIA randomized controlled trial.

BACKGROUND: Dental caries is a common disease and affects many adults worldwide. Inlay or onlay restoration is widely used to treat the resulting tooth substance loss. Two esthetic materials can be used to manufacture an inlay/onlay restoration of the tooth: ceramic or composite. Here, we present the protocol of a multicenter randomized controlled trial (RCT) comparing the clinical efficacy of both materials for tooth restoration. Other objectives are analysis of overall quality, wear, restoration survival and prognosis. METHODS: The CEramic and COmposite Inlays Assessment (CECOIA) trial is an open-label, parallel-group, multicenter RCT involving two hospitals and five private practices. In all, 400 patients will be included. Inclusion criteria are adults who need an inlay/onlay restoration for one tooth (that can be isolated with use of a dental dam and has at least one intact cusp), can tolerate restorative procedures and do not have severe bruxism, periodontal or carious disease or poor oral hygiene. The decayed tissue will be evicted, the cavity will be prepared for receiving an inlay/onlay and the patient will be randomized by use of a centralized web-based interface to receive: 1) a ceramic or 2) composite inlay or onlay. Treatment allocation will be balanced (1:1). The inlay/onlay will be adhesively luted. Follow-up will be for 2 years and may be extended; two independent examiners will perform the evaluations. The primary outcome measure will be the score obtained with use of the consensus instrument of the Fédération Dentaire Internationale (FDI) World Dental Federation. Secondary outcomes include this instrument's items, inlay/onlay wear, overall quality and survival of the inlay/onlay. Data will be analyzed by a statistician blinded to treatments and an adjusted ordinal logistic regression model will be used to compare the efficacy of both materials. DISCUSSION: For clinicians, the CECOIA trial results may help with evidence-based recommendations concerning the choice of materials for inlay/onlay restoration. For patients, the results may lead to improvement in long-term restoration. For researchers, the results may provide ideas for further research concerning inlay/onlay materials and prognosis.This trial is funded by a grant from the French Ministry of Health. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01724827.

Complication and survival of Mark II restorations: 4-year clinical follow-up.

A total of 163 monolithic restorations made from Vitablocs Mark II and luted adhesively or with resin cement were followed up for 3 to 70 months. Recall consisted of an evaluation of complete dental and hygiene status as well as quality assessment. Seven of 35 patients were lost to follow-up. Ninety-one percent of the 37 crowns, 23 partial crowns, and 89 inlays evaluated were in the posterior region. Combined survival estimate was 0.92 at the 48-month median observation time. Inlays and partial crowns performed well. Prevalence of complication and failure was highest for crowns (CP = 37.8%, FP = 21.6%). The results demonstrate that success relates to patient factors and restoration type, not luting protocol.

Catastrophic failure of a metal-on-metal total hip arthroplasty secondary to metal inlay dissociation.

Metal-on-metal bearing surfaces in total hip arthroplasty have been recently shown to have acceptable survivorship properties (J Bone Joint Surg Am. 2006;88:1183; J Bone Joint Surg Am. 2006;88:1173), and they have certain advantages and disadvantages when compared to conventional metal-on-polyethylene bearing surfaces. Like traditional metal-on-polyethylene bearings, these metal-on-metal implants may also suffer from catastrophic failure. This case report represents an unusual situation in a 57-year-old man in which dissociation of a metal inlay in a metal-on-metal total hip arthroplasty resulted in articulation of the inferior aspect of the inlay with the femoral neck, leading to femoral neck notching, extensive periprosthetic soft tissue metallosis, osteolysis, and subsequent prosthetic catastrophic failure.

Survey of accidental ingestion and aspiration at Tokyo Dental College Chiba Hospital.

The occurrence of accidental ingestion/aspiration and preventive measures were investigated at Tokyo Dental College Chiba Hospital. In addition, the characteristics of accidents at our hospital were analyzed by surveying the awareness of accidental ingestion/aspiration to utilize the data for prevention. Accidental ingestion accounted for about 30% of accidents that occurred at our hospital in fiscal 2008, but all ingested items were naturally excreted, and no accidental aspiration occurred. Accidental ingestion most frequently occurred when dental restorations were removed. Inlays and crowns were most frequently ingested, and dentists with 5 to less than 10 years of clinical experience tended to be involved in these accidents. According to the results of the questionnaire, removal of restorations was perceived as the treatment least likely to cause accidental ingestion/aspiration. Moreover, dentists who always took preventive measures against accidental ingestion/aspiration accounted for only 40% or less on average. To avoid accidental ingestion/aspiration, repeated courses and individual instruction for repeaters and the establishment of a surveillance system along with manuals to manage the violation should be emphasized.

CAD/CAM restorations and secondary caries: a literature review with illustrations.

UNLABELLED: The literature related to failures of CAD/CAM restorations, with emphasis on secondary caries, is presented. A good approximal fit of the restoration is important to prevent plaque accumulation that may lead to secondary caries. CAD/CAM restorations allow inspection of the approximal fit prior to cementation and it may explain the relatively few failures due to secondary caries. The longevity of these restorations approaches that of gold restorations. CLINICAL RELEVANCE: The requirement for CAD/CAM restorations has advanced to a stage where high quality restorations with excellent anatomy and fit can be produced. The failure rate is relatively low compared to directly placed restorations.

Influence of ceramic inlays and composite fillings on fracture resistance of premolars in vitro.

OBJECTIVE: The aim of this study was to assess the resistance of fracture of mesio-occlusal-distal (MOD) ceramic inlays and composite fillings in premolars and to compare fracture modes between the groups. MATERIAL AND METHODS: Twenty seven extracted intact human premolars were selected and divided into three groups: I - intact teeth (control group), II - MOD cavities restored with indirect ceramic inlays (Finesse, Dentsply Ceramco, USA), III - MOD cavities restored with direct composite fillings (Filtek P60, 3M ESPE, USA). The fracture resistance (N) was assessed under axial compressive loading with a metal cylinder 3.2 mm in diameter at a cross-head speed of 0.5 mm/min in a universal testing machine. The data were analyzed with ANOVA and t-test (pd< or =0.05). Fracture modes were recorded based on the degree of tooth structure and restoration damage. RESULTS: The mean force applied to cause failure for group I was 1.218 kN +/-0.223, for group II - 1.407 kN +/-0.374 and for group III - 0.941 kN +/-0.258. T-test showed significant difference between groups I and III (p=0.027), and groups II and III (p=0.008). The fracture modes observed in all groups tended to involve restoration's and cusp's fracture. CONCLUSION: It was observed that ceramic inlays in premolars have higher load to fracture value than composite fillings and similar to intact teeth. Both restorations, ceramic and composite in the premolars, tended to fracture together with palatal cusp of tooth.

On the diagnosis and management of neurocutaneous syndrome, a toxicity disorder from dental sealants.

Neurocutaneous syndrome, a newly discovered toxicity disorder, is characterized by neurological sensations, pain, depleted energy, and memory loss as well as itchy cutaneous lesions that may invite various opportunistic infections. Components in the calcium hydroxide dental sealants Dycal, Life and Sealapex have been identified as sources of the observed symptoms. Sulfonamide and neurological toxicity issues are discussed, and three case histories are presented. Additional notes on zinc oxide, Fynal, IRM, and Sultan U/P sealers are also included. Diagnostic and management protocols at the Parasitology Center, Inc., are proposed.

In vitro wear of indirect composite restoratives.

STATEMENT OF PROBLEM: Indirect composite restoratives have been improved in their wear resistance and physical properties. Several new indirect composites claim to be successfully used for full coverage crowns, but there is limited information for wear values of these new indirect composites. PURPOSE: The purpose of this study was to evaluate the wear characteristics of 7 indirect composite restoratives and to compare them with a type III gold alloy by means of an in vitro wear test. MATERIAL AND METHODS: Seven indirect composites (2 photopolymerized and 5 photo/heat-polymerized types) and a type III gold alloy (control) were used. Cylindrical Class I cavities (4-mm diameter and 3-mm depth) were prepared in occlusally flattened extracted human molars. Inlays with respective materials were fabricated on duplicated stone casts according to the manufacturers' instructions. Three types of in vitro wear tests were completed by use of the University of Alabama wear simulator. The wear tests included generalized wear as simulation of the wear during mastication, localized wear as simulation of attrition by occlusal contact, and antagonistic enamel wear, which simulated the wear of enamel created by direct contact with the restorative materials. Seven specimens were tested for each material and wear mode, and the wear depths were measured on profilometric tracings with a 2-dimensional profilometer with 1-microm accuracy. All data were analyzed by 1-way analysis of variance, and multiple comparisons were performed with Fisher's test, for which the significant level was set at.05. RESULTS: The gold alloy control exhibited a very small amount of wear in both generalized wear (0.2 +/- 0.1 microm) and localized wear (13.8 +/- 5.0 microm) as compared with all composite specimens. The antagonistic enamel wear of gold alloy was similar with the value of Sculpture. The material group, which was post polymerized or post heat-treated, included BelleGlass, Sculpture, Estenia, and Cristobal+ and showed small values ranging from 1.6 to 2.2 microm in the generalized wear. For the localized wear, Estenia exhibited the minimum value (12.8 +/- 4.9 microm) that was statistically the same as the value of the gold alloy control. However, Estenia exhibited the greatest antagonistic enamel wear value (66.0 +/- 14.0 microm) of all materials tested in this study. It was statistically significant with other materials (P