Teaching the placement of posterior resin-based composite restorations in Spanish dental schools

Current and future trends in the teaching of direct posterior composites restorations at dental schools in Canada: A cross-sectional study

OBJECTIVE

To investigate the current and future teaching of posterior composite restorations in undergraduate curricula at dental schools in Canada.

METHODS

A 23-item validated questionnaire including closed and open questions pertaining to the teaching of posterior composites was emailed to faculty members of all 10 dental schools in Canada. Responses were compiled on Excel and analysed.

RESULTS

Nine dental schools responded to the survey, resulting in a response rate of 90 %. All respondent schools taught the use of posterior composites for two- and threesurface cavities in premolars and permanent molar teeth. The didactic teaching time devoted to composites was greater than for amalgam (38 % vs 29 %). Most schools were teaching to round internal angles (n = 9, 100 %), to make slot-type cavity preparations (n = 9, 100 %), and to avoid additional preparation for mechanical retention (n = 7, 78 %). All dental schools taught the use of rubber dam for moisture control, though 4 (44 %) said that it was not always mandatory. The most common contraindications to posterior composites reported were a history of adverse reaction to composites (n = 9), poor oral hygiene (n = 6), and inability to place a rubber dam (n = 5).

CONCLUSION

The teaching of posterior composites in dental schools in Canada is wellestablished. Differences were observed in the teaching methods between dental schools in Canada and those in other countries and regions around the world. The diverse materials and techniques used across different regions may highlight a gap between clinical practice and research. Differences in the teaching between dental schools in Canada and the teaching in dental schools in other countries and regions of the world should be the subject of review.

CLINICAL SIGNIFICANCE

Graduates from dental schools in Canada may be found to be well equipped with the knowledge and skills to perform posterior composite restorations in clinical practice. However, marked variation exists in the teaching between dental schools in Canada and teaching in other countries which should be the subject of review.

Teaching of posterior composites for the restoration of permanent teeth in undergraduate dental training programmes: Systematic review and meta-analysis

OBJECTIVES

To systematically assess aspects of teaching of posterior composite restorations (PCRs) in permanent teeth in dental schools.

STUDY SELECTION

Quantitative studies reporting on dental schools' teaching regarding the placement of PCRs in permanent teeth. Random-effects meta-analyses and meta-regressions were performed. Risk of bias was assessed based on the Medical Education Research Study Quality Instrument (MERSQI).

SOURCES

Electronic databases (MEDLINE via PubMed, EMBASE via Ovid, Web of Science, and Scopus) were searched in January 2023.

DATA

Forty sources reporting on 34 studies having surveyed 1,286 dental schools were included. Overall, 92.7% (95%-CI: 88.2-95.5) of dental schools reported to teach PCRs. PCRs in three-surface Class II cavities are taught by 82.0% (95%-CI: 70.4-89.7). The mandatory use of liners in deep cavities is taught by 78.3% (95%-CI: 68.9-85.5), and 44.0% (95%-CI: 34.3-54.2) reported to teach bulk-fill composites. While most posterior restorations placed by students were composites (56.1%; 95%-CI: 46.0-65.8), 94.7% (95%-CI: 86.6-98.0) of dental schools (still) teach posterior amalgam restorations. The proportion of dental schools teaching PCRs in three-surface Class II cavities increased and the mean proportion of PCRs among all posterior restorations increased over time (padj.≤0.003).

CONCLUSIONS

The teaching of PCRs in dental schools around the world reflects the increased use of resin composite in clinical practice, with students in countries where dental amalgam continues to be used, placing more posterior composites than restorations of dental amalgam. The teaching of PCRs, which is anticipated to increase, will continue to be refined with further developments in adhesive materials, devices, instrumentation, and techniques.

CLINICAL SIGNIFICANCE

Graduating dentists can be expected to be familiar with the use of resin composites for the restoration of posterior teeth.

Changes in the teaching of prosthodontics adopted in the last academic course of the degree in Dentistry in Spain during the first period of the COVID-19 pandemic

OBJECTIVES

To investigate the impact of the COVID-19 pandemic in the teaching of prosthodontics, on the 5^th course of the Bachelor's degree in Dentistry in Spain.

METHODS

In June 2021, a two-section survey was submitted to the coordinators of prosthodontics of the 23 Spanish faculties of Dentistry. The first section was focused on the theoretical lessons, seminars, and clinical discussion sessions. The second part relied on the clinical teaching and the implemented preventive measures.

RESULTS

The response rate was 100%. By the end of the 2020-21 course, both the theoretical and practical teaching were replaced by online activities, returning to face-to face in 2021-22. While most participants preferred in-person seminars and clinical discussion sessions, concerning the theory, comparable percentages of professors chose either face-to-face or blended learning (BL). The students' satisfaction with BL is high, but they seem more attentive in-person. At the beginning of the pandemic, the most common emergency in prosthodontics was debonding. Overall, a low concern about cross-infection was noticed. The barrier measures were the mainly adopted for prevention.

CONCLUSIONS

Although the BL is appreciated in prosthodontics for theoretical lessons, face-to-face teaching appears to be the best option for seminars and clinical case discussions. The students are satisfied with BL.

CLINICAL SIGNIFICANCE

In the face of the COVID-19 pandemic, the Spanish faculties of Dentistry responded quickly to continuing offering quality education through an accelerated digitization process that has created a new paradigm. Detailed analyses of these changes may help establish plans to respond systematically to unforeseen emergencies.

Teaching of composite restoration repair in Brazilian dental schools

OBJECTIVES

The aim was to investigate aspects of the teaching of restoration repair as a minimally invasive alternative to replacing defective direct composite restorations in undergraduate curricula teaching programs in Brazilian dental schools.

METHODS

A 14-item validated survey questionnaire was mailed to directors/coordinators of operative/restorative dentistry teachers of Brazilian Dental Schools. Data were collected on demographic characteristics of the teachers and institutions, together with questions on the teaching of the repair of defective resin-based composite restorations as part of the school curriculum; the rationale behind the teaching; the nature of the teaching (preclinical and/or clinical); how techniques were taught, indications for repair, operative techniques, materials used, patient acceptability and expected longevity of completed repairs.

RESULTS

Two hundred and twenty-two (94%) directors/ coordinators of dental curricula in Brazil were contacted. One hundred and thirty-one directors/coordinators (59%) replied, providing the e-mail address from the teacher responsible for the operative/restorative dentistry program in their school. Of these, 104 responded to the questionnaire (79% response rate). Ninety-three (89%) of the participating schools reported teaching composite repairs as an alternative to replacing restorations. Of the theoretical content, 43% was taught at preclinical and clinical levels, whereas most practical experience (53%) was acquired at clinical levels. Eighty-eight schools (95%) reported tooth substance preservation being the main reason for teaching repair techniques. All schools that taught repairs reported high patient acceptability.

CONCLUSIONS

The teaching of composite restoration repair as an alternative to restoration replacement is established in undergraduate programs in most of the Brazilian dental schools surveyed.

CLINICAL SIGNIFICANCE

The reasons for teaching restoration repair in Brazil were found to be quite unanimous among teachers, especially regarding the preservation of tooth structure. Variations were found in the clinical indications for repair, suggesting the need for further investigations. Monitoring repaired restorations should be encouraged and could contribute to future studies.

'Thermo-mechanical behavior of alternative material combinations for full-arch implant-supported hybrid prostheses with short cantilevers'

OBJECTIVES

To compare the fracture resistance (FR) of three combinations of materials for full-arch maxillary implant-supported hybrid prostheses (HPs) with short cantilevers (≤ 10 mm).

METHODS

Maxillary HPs were fabricated and classified as follows (n = 5 each): Group-1 (CC-A, control): acrylic-resin-veneered Co-Cr frameworks; Group-2 (CF-A): acrylic-resin-veneered carbon-fiber mesostructures; and Group-3 (CF-R): composite-resin-veneered carbon-fiber frames. Specimens were thermal-cycled (5,000 cycles; 5 °C-55 °C; dwell time: 30 s). Vertical loads were applied until failure, first at the 10-mm-long cantilever (LC), and, afterwards, at the anterior region (AR), using a universal testing machine (crosshead speed: 0.05 mm/s). The fracture pattern was assessed by stereomicroscope and SEM. The one-way ANOVA, the Bonferroni, and the independent samples t tests, were run (α= 0.05).

RESULTS

At LC, CF-A, and CC-A samples exhibited the highest FR values (p< 0.001), showing no differences to each other. At AR, CC-A specimens recorded the highest FR, followed by CF-A samples (p< 0.001). CF-R HPs displayed the lowest FR at both locations (p< 0.001). The only group with differences between the tested sites was the CC-A, the AR being more resistant (p< 0.001). Most CC-A and CF-A HPs failed cohesively. CF-R prostheses mainly failed adhesively.

CONCLUSIONS

Maxillary HPs with short cantilevers (≤ 10 mm) made of Co-Cr or carbon-fiber veneered with acrylic resin demonstrated an adequate mechanical resistance (> 900 N).

CLINICAL SIGNIFICANCE

For maxillary HPs with cantilevers up to 10 mm, acrylic-veneered carbon- fiber mesostructures may be recommended, whereas coating carbon-fiber frames with composite resin seems not suitable.

Dental restoration selection by students at southern Saudi Arabian universities

Dental caries is a serious oral health concern and restoration of teeth is the main solution to this issue. Various restorative materials having different properties are used for posterior restoration. The aim of this study was to find that which factors can affect the choice of selection of material for posterior restoration among dental graduate students. For this purpose, a questionnaire was shared electronically among students of three different universities (King Khalid University, Jazan University, and Najran University). After collection, data were subjected to a chi-square test to check the significance. It has been observed that almost 50% of participants choose composite resin for posterior restoration. Results showed that according to most (more than 50%) of the dental students in Southern Saudi Arabia, different patient and tooth condition related factors can affect the choice for selection of restorative material.

Fracture resistance of cantilevered full-arch implant-supported hybrid prostheses with carbon fiber frameworks after thermal cycling

OBJECTIVES

This in vitro study aimed to find the best combination of mesostructure and veneering materials for full-arch implant-supported hybrid prostheses (HPs) in terms of the fracture resistance (FR) of their cantilevers.

METHODS

Three groups (n = 5 each) of maxillary HPs were fabricated: Group-1 (CC-A, control): Co-Cr frameworks coated with acrylic resin; Group-2 (CF-A): carbon fiber veneered with acrylic resin; and Group-3 (CF-R): carbon fiber coated with composite resin. All specimens were submitted to 5,000 thermal cycles (5 °C - 55 °C, dwell time: 30 s), and subjected to a single cantilever bending test in a universal testing machine (crosshead speed: 0.5 mm/min) until failure. The fracture pattern was assessed using stereo microscope and SEM. The one-way ANOVA and Bonferroni tests were run (α= 0.05).

RESULTS

The FR yielded significant differences among the three groups (p< 0.001). CC-A samples reached the highest FR values (p ≤ 0.001), whereas both CF-A and CF-R HPs exhibited the comparably (p = 0.107) lowest FR. CC-A specimens failed cohesively (100%): mostly without chipping (80%). CF-A mesostructures were always broken at the connections of the distal implants. CF-R prostheses often failed adhesively (80%).

CONCLUSIONS

The HPs made of Co-Cr veneered with acrylic demonstrated the best mechanical behavior, being the only group whose 13-mm long cantilevers exceeded the clinically acceptable FR of 900 N. The HPs constructed with carbon fiber frameworks showed, additionally, more unfavorable fracture patterns.

CLINICAL SIGNIFICANCE

For HPs with cantilevers up to 13 mm, Co-Cr mesostructures coated with acrylic may represent the optimum combination of materials.

'Role of the modulating factors on the self-perceived OHRQoL of fully dentate subjects and wearers of screw-retained and cement-retained implant-supported FPDs: A cross-sectional study'

OBJECTIVES

This research aimed to compare the oral health-related quality of life (OHRQoL) between fully dentate subjects and edentulous patients wearing implant-supported fixed partial dentures (i-FPDs). The clinical conditions of both types of restorations were evaluated.

METHODS

Participants were assigned to: Group-1 (SR, n= 50): screw-retained i-FPD wearers; Group-2 (CR, n= 50): cement-retained i-FPD wearers; and Group-3 (ND, n= 50): dentate subjects with a healthy natural dentition (controls). Patients answered the OHIP-14sp and QoLIP-10 questionnaires. Data related to sociodemographics, prosthesis features, peri-implant status, complications, and subjective evaluations, were compiled. Potential modulators of the OHRQoL and the i-FPDs' clinical conditions were assessed using non-parametric tests (α= 0.05).

RESULTS

ND individuals were the least satisfied (OHIP-14sp; p< 0.001). Both prosthodontic groups reported similar levels of wellbeing, excluding the speaking difficulties, which were lower for SR wearers as shown by both scales (p= 0.001). The most discontented patients (OHIP-14sp) were: women (p= 0.022), under 65 years (p= 0.03), without partner (p< 0.001) and having a crown (p= 0.033). The level of education/schooling also affected the OHIP-14sp scores (p< 0.001). Implant mobility and peri-implantitis were more frequent among CR wearers (p-values= 0.008 and 0.05, respectively).

CONCLUSIONS

The OHRQoL of both prosthodontic groups was comparably higher than that of the dentate subjects, who were the most nonconformist. The self-perceived satisfaction was mainly modulated by sociodemographic factors.

CLINICAL SIGNIFICANCE

Overall, the retention system did not impact the OHRQoL, prosthetic problems, and subjective evaluations of i-FPD wearers. However, the cementation may increase the risk of peri-implant diseases.

Composite versus Amalgam Restorations Placed in Canadian Dental Schools

OBJECTIVES

To investigate the latest teaching policies of posterior composite placement versus amalgam and to determine the actual numbers of posterior composites versus amalgam restorations placed in Canadian dental schools, over the years from 2008 to 2018.

METHODS

Emails were sent to Chairs/Heads of Restorative Departments and Clinic Directors of all 10 Canadian dental schools to collect data in the forms of: 1) Questionnaire on current teaching policies of posterior composite and amalgam restorations; 2) data entry form to collect the actual numbers of posterior composite and amalgam restorations placed in their clinics.

RESULTS

For the teaching questionnaire, the response rate was 90% (n=9). Seven (78%) of the responding schools reported that they assign 25%-50% of their preclinical restorative teaching time towards posterior composite placement. While, three (33%) of the responding schools allocated 50%-75% of their restorative teaching towards amalgam placement. Data entry response rate was 80% (n=8). Amalgam material was dominant in the restoration distribution from 2008 to 2012. While from 2013 to 2018, resin composite material was dominant in all eight responding schools. Linear regression analysis revealed a significant increasing trend in placing posterior composites in all the responding schools over time (p<0.05).

CONCLUSIONS

Data analysis revealed a clear trend towards an increase of posterior composite restoration placement and a decrease in the number of amalgam restorations placed. However, the teaching time assigned for posterior composite is not aligned with quantity placed. Review and adjustment of time allocated for teaching and training of each material are recommended.

A Contemporary Evaluation on Posterior Direct Restoration Teaching among Undergraduates in Dental Schools in Malaysia

There is a current trend to restore posterior teeth with composite resin due to increasing demands on natural tooth colour restoration and increased concern about the safety of amalgam restorations. The objective was to evaluate the current teaching of posterior direct restoration among restorative dental lecturers in Malaysia compared to available international literature. An online questionnaire, which sought information on the teaching of posterior restoration was developed and distributed to 13 dental schools in Malaysia. The response rate for the questionnaire was 53.8%. The most popular posterior restoration teaching methods among the respondents were lecture (95.7%), demonstration (87.0%) and problem-based learning (PBL) (73.9%), while continuous assessment and a practical competency test (82.6%) were the most popular assessment methods. Placing a hard setting calcium hydroxide and GIC base for deep cavity restored by composite restoration was taught in 79.2% of cases. The standard protocols for posterior composite restoration were incremental filling in deep cavity (87.5%), using circumferential metal bands with wooden wedge (91.7%), with a total etch system (95.8%), using a light emitting diode (LED) light curing unit (91.7%), finishing using water cooling (80%) and finishing with a disc (87.5%). Graduates from dental schools in Malaysia received similar theoretical, preclinical and clinical teaching on posterior restoration techniques, although there were variations in the delivery methods, techniques and assessments, pointing to a need for uniformity and consensus.

Current and future trends in the teaching of direct posterior resin composites in Malaysian dental schools: a cross-sectional study

OBJECTIVE

To investigate the current and future teaching of posterior composite restorations in undergraduate curricula in Malaysian dental schools.

METHODS

A 24-item validated questionnaire including closed and open questions on the teaching of posterior composites was emailed to faculty members in all 13 Dental Schools in Malaysia. Responses were compiled on Excel and analysed.

RESULTS

All 13 dental schools responded to the survey yielding a 100 % response. All schools indicated the use of posterior composites for 2- and 3-surface cavities in premolars and molars. The didactic teaching time devoted to composites was greater than for amalgam (38 h vs 29 h). Clinically, most posterior restorations placed by students were composites (average 74.1 %, range 10 %-100 %); the remaining 25.9 % were amalgams (range, 0 %-50 %). Slot-type cavities were the preparation techniques most commonly taught (n = 11,84.6 %). The use of rubber dam for moisture control was mandatory in most schools (n = 11, 84.6 %). History of adverse reaction to composites was found to be the most common contraindication to composite placement. The phase down of teaching and use of amalgam in Malaysia is expected to occur within the next six years.

CONCLUSION

The trend to increase the teaching of posterior composites reported for other countries is confirmed by the findings from Malaysian dental schools. Notwithstanding this trend, the use of amalgam is still taught, and future studies are required to investigate the implications of the phase down of amalgam in favour of posterior composites.

CLINICAL SIGNIFICANCE

Notwithstanding the increase in the teaching of posterior composites there is a pressing need to update and refine clinical guidelines for the teaching of posterior composites globally.

Dental cavity liners for Class I and Class II resin-based composite restorations

BACKGROUND

Resin-based composite (RBC) is currently accepted as a viable material for the restoration of caries for posterior permanent teeth requiring surgical treatment. Despite the fact that the thermal conductivity of the RBC restorative material closely approximates that of natural tooth structure, postoperative hypersensitivity is sometimes still an issue. Dental cavity liners have historically been used to protect the pulp from the toxic effects of some dental restorative materials and to prevent the pain of thermal conductivity by placing an insulating layer between restorative material and the remaining tooth structure. This is an update of the Cochrane Review first published in 2016.

OBJECTIVES

The objective of this review was to assess the effects of using dental cavity liners in the placement of Class I and Class II resin-based composite posterior restorations in permanent teeth in children and adults.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 12 November 2018), the Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 10) in the Cochrane Library (searched 12 November 2018), MEDLINE Ovid (1946 to 12 November 2018), Embase Ovid (1980 to 12 November 2018) and LILACS BIREME Virtual Health Library (Latin American and Caribbean Health Science Information database; 1982 to 12 November 2018). We searched ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

We included randomized controlled trials assessing the effects of the use of liners under Class I and Class II posterior resin-based composite restorations in permanent teeth (in both adults and children). We included both parallel and split-mouth designs.

DATA COLLECTION AND ANALYSIS

We utilized standard methodological procedures prescribed by Cochrane for data collection and analysis. Two review authors screened the search results and assessed the eligibility of studies for inclusion against the review inclusion criteria. We conducted risk of bias assessments and data extraction independently and in duplicate. Where information was unclear we contacted study authors for clarification.

MAIN RESULTS

Eight studies, recruiting over 700 participants, compared the use of dental cavity liners to no liners for Class I and Class II resin-based composite restorations.Seven studies evaluated postoperative hypersensitivity measured by various methods. All studies were at unclear or high risk of bias. There was inconsistent evidence regarding postoperative hypersensitivity (either measured using cold response or patient-reported), with a benefit shown at some, but not all, time points (low-quality evidence).Four trials measured restoration longevity. Two of the studies were judged to be at high risk and two at unclear risk of bias. No difference in restoration failure rates were shown at 1 year follow-up, with no failures reported in either group for three of the four studies; the fourth study had a risk ratio (RR) 1.00 (95% confidence interval (CI) 0.07 to 15.00) (low-quality evidence). Three studies evaluated restoration longevity at 2 years follow-up and, again, no failures were shown in either group.No adverse events were reported in any of the included studies.

AUTHORS' CONCLUSIONS

There is inconsistent, low-quality evidence regarding the difference in postoperative hypersensitivity subsequent to placing a dental cavity liner under Class I and Class II posterior resin-based composite restorations in permanent posterior teeth in adults or children 15 years or older. Furthermore, no evidence was found to demonstrate a difference in the longevity of restorations placed with or without dental cavity liners.

Phase down of amalgam. Awareness of Minamata convention among Jordanian dentists

OBJECTIVES

To assess the knowledge of Jordanian dentists toward phase down of dental amalgam as recommended by the Minamata Convention, and their training and competency in placing posterior composites.  Methods: This study was conducted through structured questionnaire interviews with randomly selected cohort of dentists in Jordan between March 2015 and June 2015. Out of 230 dentists who were invited, 196 (85.2%) agreed to participate. Dentists were asked if they know about the Minamata Convention. They were also asked about their training in placement of posterior composite.  Results: Out of the 196 interviewed, only 13.8% know about Minamata Convention and 17% had an undergraduate training in favor of placing composites in posterior teeth. Approximately 50% of those dentists were not trained in using rubber dam when placing posterior composites, while only 38.3% had training in sectional matrix placement. Undergraduate training did not influence (p=0.00) the dentists' decision to remove old amalgam based on patient's demands. Only 28.1% were of the opinion of discontinuing the use of amalgam due to its alleged health and environmental hazards. There was no general agreement on the type of composite, liner, and bonding strategy when placing posterior composites. Conclusion: Dentists are not well informed on the Minamata Convention and the phase down of amalgam. Training in posterior composite placement should be given more room in undergraduate curriculum and continuous dental education.

Dental cavity liners for Class I and Class II resin-based composite restorations

BACKGROUND

Resin-based composite (RBC) is currently accepted as a viable material for the restoration of caries for posterior permanent teeth requiring surgical treatment. Despite the fact that the thermal conductivity of the RBC restorative material closely approximates that of natural tooth structure, postoperative hypersensitivity is sometimes still an issue. Dental cavity liners have historically been used to protect the pulp from the toxic effects of some dental restorative materials and to prevent the pain of thermal conductivity by placing an insulating layer between restorative material and the remaining tooth structure.

OBJECTIVES

The objective of this review was to assess the effects of using dental cavity liners in the placement of Class I and Class II resin-based composite posterior restorations in permanent teeth in children and adults.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 25 May 2016), the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 4) in the Cochrane Library (searched 25 May 2016), MEDLINE Ovid (1946 to 25 May 2016), Embase Ovid (1980 to 25 May 2016) and LILACS BIREME Virtual Health Library (Latin American and Caribbean Health Science Information database; 1982 to 25 May 2016). We searched ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

We included randomized controlled trials assessing the effects of the use of liners under Class I and Class II posterior resin-based composite restorations in permanent teeth (in both adults and children). We included both parallel and split-mouth designs.

DATA COLLECTION AND ANALYSIS

We utilized standard methodological procedures prescribed by Cochrane for data collection and analysis. Two review authors screened the search results and assessed the eligibility of studies for inclusion against the review inclusion criteria. We conducted risk of bias assessments and data extraction independently and in duplicate. Where information was unclear we contacted study authors for clarification.

MAIN RESULTS

Eight studies, recruiting over 700 participants, compared the use of dental cavity liners to no liners for Class I and Class II resin-based composite restorations.Seven studies evaluated postoperative hypersensitivity measured by various methods. All studies were at unclear or high risk of bias. There was inconsistent evidence regarding postoperative hypersensitivity (either measured using cold response or patient-reported), with a benefit shown at some, but not all, time points (low-quality evidence).Four trials measured restoration longevity. Two of the studies were judged to be at high risk and two at unclear risk of bias. No difference in restoration failure rates were shown at one year follow-up, with no failures reported in either group for three of the four studies; the fourth study had a risk ratio (RR) 1.00 (95% confidence interval (CI) 0.07 to 15.00) (low-quality evidence). Three studies evaluated restoration longevity at two years follow-up and, again, no failures were shown in either group.No adverse events were reported in any of the included studies.

AUTHORS' CONCLUSIONS

There is inconsistent, low-quality evidence regarding the difference in postoperative hypersensitivity subsequent to placing a dental cavity liner under Class I and Class II posterior resin-based composite restorations in permanent posterior teeth in adults or children 15 years or older. Furthermore, no evidence was found to demonstrate a difference in the longevity of restorations placed with or without dental cavity liners.

Managing the phase-down of amalgam: Part I. Educational and training issues

Following the recently agreed Minamata Convention, a phase-down in the use of dental amalgam will become a priority for the profession. With a lead-in period of a number of years, important changes in the mind-set of the profession are required to ensure that patient safety is not compromised. Posterior composites have been a viable, and in many cases preferable, alternative to amalgam for many years. However, notwithstanding considerable developments in dental school teaching on the application and placement of posterior composites, growing evidence to support the use of composites in the restoration of posterior teeth and advances in composite systems, many practitioners remain reluctant to place composite rather than amalgam. This paper considers the present and future use of posterior composites and highlights ways in which dental school teaching and continuing professional development (CPD) may contribute to the successful phase-down, and now inevitable discontinuation, in the use of dental amalgam.

Self-perceived changes in oral health-related quality of life after receiving different types of conventional prosthetic treatments: a cohort follow-up study

OBJECTIVES

To evaluate the changes in oral health-related quality of life (OHRQoL) reported by subjects treated with conventional prostheses.

METHODS

A consecutive sample of 153 patients seeking prosthodontic rehabilitation was recruited. Socio-demographic and prosthetic-related factors (Eichner Index; number of occlusal, aesthetic, and lost units) were registered. Baseline impacts on OHRQoL were collected using the OHIP-14 questionnaire. One month after treatment, the participants answered whether the prostheses had generated better, equal, or poorer effects within the 14 items of a retrospective scale (Post-OHIP). The study patients were compared with the reference population (P-population; n=123) in terms of OHRQoL. Such P-population consisted of Spanish adults wearing conventional dental prostheses who were not seeking any dental treatment. The reliability and validity of the tests applied and the factor structure of the Post-OHIP were investigated. A Poisson regression model was calculated to predict what items would change favourably after treatment.

RESULTS

Four prosthetic cohorts were established according to the types of rehabilitations performed: 1-FDPs: metal-ceramic fixed dental prostheses; 2-M-RPDs: metal-based removable partial dentures; 3-ADs: acrylic partial dentures and 4-CDs: complete dentures. Both tests confirmed adequate psychometric properties. Most items of the Post-OHIP consistently loaded on a single factor. Patients requiring ADs or CDs reported significantly lower baseline OHRQoL than those needing M-RPDs or FDPs. Pain/discomfort was the only hampering issue subsequent to removable rehabilitation. M-RPDs are expected to provide the significantly highest therapeutic improvements.

CONCLUSIONS

Patients perceived benefits in chewing ability, aesthetics and satisfaction with their mouth after receiving conventional dental prostheses.

CLINICAL SIGNIFICANCE

Conventional prosthetic therapy enhances patients' overall well-being although it can cause discomfort and chewing dysfunction in more than 20% of subjects. Metal-based removable partial dentures are the most predictable in terms of patient satisfaction. The higher the clinical impairment felt by patients, the higher the increase in OHRQoL after rehabilitation.