Adam Louie Al-Bendawi
5th, OF group 13
A comparison between digital and conventional full removable
dental prostheses fabrications for maxillaryedentulous dental
arch: systematic review of literature
Master’s Thesis
Supervisor
Lecturer Dr. Rimantas Ožiūnas
LITHUANIAN UNIVERSITY OF HEALTH SCIENCES MEDICAL ACADEMY
FACULTY OF ODONTOLOGY ORTHOPEDIC CLINIC
A comparison between digital and conventional full removable dental prostheses fabrications for maxillary edentulous dental arch: systematic review of literature
Master’s Thesis
The thesis was done
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EVALUATION TABLE OF THE MASTER’S THESIS
OF THE TYPE OF SYSTEMIC REVIEW OF SCIENTIFIC LITERATURE Evaluation: ... Reviewer: ...
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z MT parts MT evaluation aspects
Compliance with MT requirements and evaluation
Yes Partially No 1 Summary (0.5
point)
Is summary informative and in compliance with the thesis
content and requirements? 0.3 0.1 0
2 Are keywords in compliance with the thesis essence? 0.2 0.1 0 3
Introduc-tion, aim and tasks
(1 point)
Are the novelty, relevance and significance of the work
justified in the introduction of the thesis? 0.4 0.2 0 4 Are the problem, hypothesis, aim and tasks formed clearly and
properly? 0.4 0.2 0
5 Are the aim and tasks interrelated? 0.2 0.1 0
6 Selection criteria of the studies, search methods and strategy (3.4 points)
Is the protocol of systemic review present? 0.6 0.3 0 7 Were the eligibility criteria of articles for the selected protocol
determined (e.g., year, language, publication condition, etc.) 0.4 0.2 0 8
Are all the information sources (databases with dates of coverage, contact with study authors to identify additional studies) described and is the last search day indicated?
0.2 0.1 0
9
Is the electronic search strategy described in such a way that it could be repeated (year of search, the last search day; keywords and their combinations; number of found and selected articles according to the combinations of keywords)?
0.4 0.1 0
10
Is the selection process of studies (screening, eligibility, included in systemic review or, if applicable, included in the meta-analysis) described?
0.4 0.2 0
11
Is the data extraction method from the articles (types of investigations, participants, interventions, analysed factors, indexes) described?
0.4 0.2 0
12 Are all the variables (for which data were sought and any
assumptions and simplifications made) listed and defined? 0.4 0.2 0 13
Are the methods, which were used to evaluate the risk of bias of individual studies and how this information is to be used in data synthesis, described?
0.2 0.1 0
14 Were the principal summary measures (risk ratio, difference in
means) stated? 0.4 0.2 0 15 Systemiza-tion and analysis of data (2.2 points)
Is the number of studies screened: included upon assessment for eligibility and excluded upon giving the reasons in each stage of exclusion presented?
0.6 0.3 0
16
Are the characteristics of studies presented in the included articles, according to which the data were extracted (e.g., study size, follow-up period, type of respondents) presented?
0.6 0.3 0
17
Are the evaluations of beneficial or harmful outcomes for each study presented? (a) simple summary data for each intervention group; b) effect estimates and confidence intervals)
0.4 0.2 0
18 Are the extracted and systemized data from studies presented
in the tables according to individual tasks? 0.6 0.3 0 19
Discussion (1.4 points)
Are the main findings summarized and is their relevance
indicated? 0.4 0.2 0
20 Are the limitations of the performed systemic review
discussed? 0.4 0.2 0
22
Conclusions (0.5 points)
Do the conclusions reflect the topic, aim and tasks of the
Master’s thesis? 0.2 0.1 0
23 Are the conclusions based on the analysed material? 0.2 0.1 0
24 Are the conclusions clear and laconic? 0.1 0.1 0
25
References (1 point)
Is the references list formed according to the requirements? 0.4 0.2 0 26 Are the links of the references to the text correct? Are the
literature sources cited correctly and precisely? 0.2 0.1 0 27 Is the scientific level of references suitable for Master’s
thesis? 0.2 0.1 0
28 Do the cited sources not older than 10 years old form at least
70% of sources, and the not older than 5 years – at least 40%? 0.2 0.1 0 Additional sections, which may increase the collected number of points
29 Annexes Do the presented annexes help to understand the analysed
topic? +0.2 +0.1 0
30
Practical
recommen-dations
Are the practical recommendations suggested and are they
related to the received results? +0.4 +0.2 0
31 Were additional methods of data analysis and their results
used and described (sensitivity analyses, meta-regression)? +1 +0.5 0 32
Was meta-analysis applied? Are the selected statistical methods indicated? Are the results of each meta-analysis presented?
+2 +1 0
General requirements, non-compliance with which reduce the number of points 33
General require-ments
Is the thesis volume sufficient (excluding annexes)?
15-20 pages (-2 points)
<15 pages (-5 points) 34 Is the thesis volume increased artificially? -2 points -1 point
35 Does the thesis structure satisfy the requirements of Master’s thesis? -1 point -2 points 36 Is the thesis written in correct language,
scientifically, logically and laconically? -0.5 point -1 points 37 Are there any grammatical, style or computer
literacy-related mistakes? -2 points -1 points 38 Is text consistent, integral, and are the volumes of
its structural parts balanced? -0.2 point -0.5 points
39 Amount of plagiarism in the thesis. >20%
(not evaluated) 40
Is the content (names of sections and sub-sections and enumeration of pages) in compliance with the thesis structure and aims?
-0.2 point -0.5 points
41
Are the names of the thesis parts in compliance with the text? Are the titles of sections and sub-sections distinguished logically and correctly?
-0.2 point -0.5 points
42 Are there explanations of the key terms and
abbreviations (if needed)? -0.2 point -0.5 points
43 Is the quality of the thesis typography (quality of
printing, visual aids, binding) good? -0.2 point -0.5 points *In total (maximum 10 points):
*Remark: the amount of collected points may exceed 10 points. Reviewer’s comments: ___________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ________________________________ ___________________________ Reviewer’s name and surname Reviewer’s signature
Table of contents
INRODUCTION ... 8
Aim and Tasks ... 11
1. SELECTION CRITERIA OF THE STUDIES. SEARCH METHODS AND STRATEGY ... 12
1.1 Methods ... 12
1.2 Inclusion/Exclusion Criteria ... 12
1.3 Online search of databases ... 13
1.4 Study Selection ... 16
1.5 Quality and risk of bias assessment for the included studies ... 18
2. SYSTEMIZATION AND ANALYSIS OF DATA ... 20
2.1 Results ... 20
2.1.1 Descriptive results... 20
3. DISCUSSION ... 24
3.1 Limitation to this systematic review ... 27
CONCLUSION ... 29
PRACTICAL RECOMMENDATIONS ... 30
REFERENCES ... 31
ANNEXES ... 34
Annex 1. Scheme of complete removable dental prostheses’ fabrication steps by Additive manufacturing (3D printing method). ... 34
Annex 2. Scheme of complete removable dental prostheses’ fabrication steps by milling manufacturing. ... 35
SUMMARY
Aim. To compare the fabrication of digital and conventional maxillary full removable dental
prostheses with regard to their clinical performance, accuracy, retention and fit, speech and esthetics,fabrication time, patient/prosthodontists’ satisfaction as well as fabrication-related complications.
Materials and methods. A search of English literature from 2007 to 2017 was conducted in the
PubMed, Web of Science, ScienceDirect, Scopus and Cochrane Library databases for Mesh and free text termer. The search resulted in 1552 articles. The articles were filtered and then reviewed at title, abstract, and full text levels and the duplicates were sorted out. After following the
inclusion/exclusion criteria, 5 articles comparing the two types of interventions were left and included in the review.
Results. 5 studies were selected for the qualitative analysis. Higher scores for the digital compared
to the conventional complete removable dental prostheses (CRDPs) were expressed by the
participants in several studies with respect to clinical performance, accuracy, and retention and fit. No significant difference between conventional and digital CDs with regard to esthetics and phonetics/speech was shown by 3 studies. Significantly higher patient/prosthodontists’ satisfaction and preference for digital CRDPs were also reported in two studies. Only one study showed no significant difference betwen CRDPs fabricated by the digital and conventional methods regarding the denture stability and comfort as well as patient/prosthodontists’ satisfaction and preference. Less fabrication time and higher technique accuracy offered by the digital method were reported by two studies, while one study reported longer working time for the digital procedure. Complications and problems encountered during the CRDPs fabrication by the digital method were also reported in three studies.
Conclusion. The results reported by several of the clinical studies, comparing the digital and
conventional CRDPs productions, included in this review reveal better denture processing accuracy, retention, functional performance, time efficiency and higher patient/prosthodontists’ preference and satisafaction with the digital CD.
Key words: CAD/CAM, Complete denture, Edentulous, Maxilla, Conventional, Removable,
8
INRODUCTION
Edentulism, or total loss of natural teeth, has long been and still a major public health problem all over the world. Among the elderly population, it represnets a condition where patients’ability to perform important daily fuctions such as proper speaking and masticating is compromised. Most edentulous elders suffer poor oral and general health conditions, nutritional status as well as quality of life [1].
Different factors lead to edentulism. Microbial diseases such as caries, periodontal diseases and their complications in association with neglected oral hygiene are the most prevalent factors [2]. Complete natural tooth loss results also from traumatic, therapeutic, or iatrogentic causative factors [3].
Rehabilitation of edentulous patients includes such interventions as complete removable dental prostheses (CRDPs), implant-retained overdentures and, for certain cases, implant supported full arch fixed complete denture prostheses. Since edentulism is largely correlated with patients of low social class, treatment with complete removable dental prosthesis is still the most affordable option [1]. Hence, rehabilitation with complete removable dental prosthesis is the most conventional prosthetic treatment for edentulous patients who suffer anatomical, psychological, or financial restrictions that limit implant therapy [4].The conventional method of fabricating complete removable dental prosthesis (CRDP) has been introduced for over 80 years. It has remained relatively stable and has been effective and reliable since then [5].
However, a set of manually-performed clinical and laboratory procedures are involved in the
conventional CRDP construction. An edentulous patient is usually required to pay at least 5 visits to the dental clinic in order to obtain a complete denture. Accordingly, a number of disadvantages accompany these procedures including high costs associated with these visits, the costs and time required for the laboratory work, and in some cases, the difficulty to perform the process, especially for edentulous elders who have multiple-diseases and/or live in care providing facilities [6, 7]. Moreover, the quality for the manually designed and constructed complete dentures is hardly ensured. The conventional fabrication method of dentures employs mostly heat-cured
polymethylmethacrylate (PMMA) materials, hence some of the problems that accompany the manufactured dentures utilizing these materials are: 1) polymerization shrinkage that leads to reduced fit between the denture bearing tissues and the base; 2) lack of dimentional stability; 3) increased content of residual monomers; 4) tendency to absorption of water; 5) changeability of colour; and 6) the difficulty in producing a proper duplication of the denture.
9 Another serious problem is the denture porosity. Porosity, when increased, disturb both denture’s esthetics and mechanical characteristics. It also results in harbouring microorganisms such as
Candida albicans underneath the denture which, in turn, increases the infecion potential [8, 9].
In addition, a significant number of conventional complete denture wearers have shown dissatisfaction. Most of these patients’ complains are about prosthesis’ lack of stability and/or retention and decreased speaking and chewing abilities [10].
To overcome the problems associated with conventional complete removable dental prosthesis, Computer-aided design and computer-aided manufacturing (CAD/CAM) technique has been introduced for designing and fabricating complete dentures.CAD/CAM fabrication of CRDPs is mainly accomplished by either additive manufacturing, 3D printing (also known as rapid prototyping(RP)), or by a subtractive, computerized numerical control (CNC) milling manufacturing.
Additive manufacturing or 3D printing is a process by which materials are joined layer by layer to produce models utilizing computerized three-dimensional (3D) data. This technology was
introduced by Charles Hull in the late 1980s and has been employed in the field of medicine for the production of anatomical 3D models for surgery since 1990s.
Additive manufacturing is subclassified in accordance to the used materials and methods. In the dental field, stereolithography apparatus (SLA) and selective laser sintering (SLS) are the most commonly employed methods. SLA method utilizes utraviolet light (UV) polymerizable resin materials and has widley been applied for fabrication dental restorations. 3D printing is used for the fabrication of craniomaxillofacial and orthopedic prostheses, dental crowns, inlays and onlays, frameworks for dental restorations and implants [11, 12, 13, 14].
Unlike the additive manufacturing process, the subtractive manufacturing or milling uses end-milling of solid block materials such as metal, resin, or zirconia using CSN machine to produce a physical model [15].This process has long been associated with dentistry, especially in the fabrication of dental crown copings and frameworks for bridge restoration [15].
As for the digital fabrication of removable complete dental prostheses, several digital denture systems such as Dentca CAD/CAM system (Dentca Inc., Los Angeles), AvaDent digital dentures (Global Dental Science LLC, Scottsdale, Ariz.), Pala Digital Dentures (Heraeus Kulzer, Hanau, Germany), Weiland Digital denture (Ivoclar Vivadent AG, Schann, Liechtenstein) are currently available. Dentica and Pala systems employ the additive manufacturing (3D printing) to fabricate a trial denture by using stereolithpgraphy. On the other hand, the AvaDent and Weiland systems utilize milling process for the production of denture base from a pre-polymerized resin block [16, 1Compared to the conventional complete removable dental prosthesis’ fabrication process, where
10 the edentulous patient is required to have 5 clinical visits, the employment of the digital denture system has decreased the patient‘s visits to the dental clinic to 2 visits, which are needed for denture fabrication and delivery [18].
Apart from the reduced clinical visits, the following potential advantages are also offered including: 1) the dentures are fabricated with materials of high and controlled quality; 2) decreased chair time and costs of the treatment; 3) improved fit as the polymerization shrinkage is minimal due to the pre-polymerized acrylic resin material used for milling the denture base; 4) reduced porosity and hence minimal attachment of microorganisms; and 5) accessible production of extra or replacement denture in case of denture loss or breakage[19].
However, this digital technology is not free of shortcomings. Bidra A et al. states that some of the important disadvantages that associate the digital denture fabrication are the difficulty of evaluating the vertical dimension of occlusion (VDO) and vertcial dimension at rest (VDR), the difficulty of maintaining maxillary incisal edge position and lip support; the difficulty of defining the
mandibular occlusal plane; the lack of trial denture for intraoral assessment before fabricating the definitive denture; and the high costs of the laboratory and the availabe materials [9].
Despite the fact that the first clinical reports describing the manufacturing process of CRDPs by using the CAD/CAM technology were introduced in the early 1990s, solid outcomes regarding the clinical performance, fabrication accuracy and efficacy as well as patient’s satisfaction provided by this technology are still limited in scientific publications [19, 8].
Therefore, the aim of this systematic review is to compare the fabrication of digital and
conventional maxillary full removable dental prostheses with regard to their clinical performance, accuracy, retention and fit, fabrication time, speech and esthetics, patient/prosthodontists’
11
Aim and Tasks
The aim of this systematic review is to compare the fabrication of digital and conventional maxillary full removable dental prostheses with regard to their clinical performance, accuracy, retention and fit, speech and esthetics, fabrication time, patient/prosthodontists’ satisfaction as well as fabrication-related complications.
Tasks:
1. To compare the digital to conventional maxillary complete removable dental prostheses, with regard to clinical efficacy, accuracy, speech and esthetics, fabrication time and patient/prosthodontists’ satisfaction and preference;
2. To evaluate the denture retention and fit between the 2 methods of fabrications;
3. To report on fabrication complications associated with the procedures of digital complete removable dental prostheses.
12
1. SELECTION CRITERIA OF THE STUDIES. SEARCH METHODS AND
STRATEGY
1.1 Methods
The review is based on search of literature conducted in the PubMed, Web of Science,
ScienceDirect, Scopus and Cochrane Library databases for titles, abstracts and full articles within 10 years period. This is a review of clinical trials/studies in which conventional technique and digital, computer-aided design and computer-aided manufacturing (CAD/CAM) technique, i.e. complete removable dentures fabricated either by milling or 3D printing, have been used for the fabrication of full removable dental prosthesis for upper jaw and then compared.
It is worth mentioning that keyword “CAD/CAM” was used to replace the keywords “3D printing” and “milled” which were firstly used during the search of literature. The reason why these two keywords were replaced was they resulted in limited number of studies. The keyword
“CAD/CAM”, however, satisfied the purpose and yielded significant number of results.
The requirements of the PRISMA statement were followed for conducting this systematic review. The strategy of the literature search was developed by using Mesh and free text termer and
customized as appropriate before application in each database. The three terms "CAD/CAM", "Complete denture" and "Edentulous" were combined with other free terms "Maxilla",
"Conventional", "Removable” and "Fabrication".
1.2 Inclusion/Exclusion Criteria
The articles were reviewed according to inclusion / exclusion criteria described in table 1.
Table 1.Inclusion/exclusion criteria
Inclusion criteria Exclusion criteria
Study type
-Clinical studies,
-Studies comparing the two; digital and conventional fabrication techniques of CRDPs, - Studies on humans. -Reviews, -Case/clinical reports, -Summaries, -Abstracts, -Descriptive studies; -In vitro studies
-Studies not comparing the two techniques of fabrication
-Studies on animals, Study time-period Within 10-years
and 5-years periods
Older than 10-year period
Language English Other languages
13
1.3 Online search of databases
The searches in the online databases: Pubmed, ScienceDirect, Web of Science, Scopus and
Cochrane Library are described in (Tables 2-6). The online searches were based on a combination of keywords: “CAD/CAM”, “Complete denture”, “Edentulous”, “Maxilla”, “Conventional”, “Removable” and “Fabrication”, and the filters “Humans”, “10 years” and “5 years”.
Table 2. Search strategy
N/A, not applicable
In the first search of the database Pubmed (Table 2), the keyswords “CAD/CAM and complete denture” were combined and yielded 96 results. After applying the filter “Humans”, 71 results appeared. By adding the time filter “10 years”, 64 items showed up and when the latter filter was replaced by “5 years” filter, 39 items resulted.
Keeping the filters intact, the keyword “edentulous” was added and yielded 59. Using the filter “humans”, 47 showed up. After applying the time filters “10 years” and “5 years”, 42 and 18 hits were filtered respectively.
In the next search, the keyword “Maxilla” is joined to the previous keywords. Using the filter “Humans”, 15 items resulted. Further filtration with time filter “10 years” yielded 11 scores and the time filter “5 years” revealed 4 scores when employed afterwards.
In order to find out an alternative search results and without eliminating the filter “humans”, the keyword “Maxilla” was exchanged by the keyword “conventional”. 7 results were gathered without employing any time filter. The past 10 years filtration gave 6 hits and the 5-years filtration resulted in 5 items.
Date: 22.10.2017 Database: PubMed Search
No.
Key words combinations Filters’ results
No filter Humans Human +10 years Human +5 years
1. CAD/CAM AND complete denture 96 71 64 39
2. #1 AND edentulous 59 47 42 18
3. # 2 AND maxilla 15 15 11 4
4. #2 AND conventional 13 7 6 5
5. # 2 AND removable 13 12 8 3
14 For the next search the keyword “Conventional” was swapped with “Removable”. While
maintaining the filter “Humans” in its place, 12 results appeared. Once again time filters “10 years” was utilized and 8 items came up. The “5 years” time filter revealed 3 items after being applied. In the last search, the keyword “fabrication” was used instead of the keyword “conventional” and was added to the previous keyword combination “CAD/CAM AND complete denture AND edentulous”. Utilizing the filter “humans”, 21 results emerged. The 10 years filtration option showed 19 items, while the past 5 years showed 9 articles.
The above described search strategy has been applied to the other 4 databases: ScienceDirect, Web of Science, Scopus and Cochrane Library described in (Tables 3-6) below.
Table 3. Search strategy
N/A, not applicable
Table 4. Search strategy
N/A, not applicable
Date: 22.10.2017 Database: ScienceDirect Search
No.
Key words combinations Filters’ results
No filter Humans 10 years 5 years
1. CAD/CAM AND complete denture 197 N/A 144 117
2. #1 AND edentulous 153 N/A 107 83
3. # 2 AND maxilla 96 N/A 67 50
4. #2 AND conventional 122 N/A 85 69
5. # 2 AND removable 140 N/A 94 64
6. # 2 AND fabrication 125 N/A 83 66
Date: 22.10.2017 Database: Web of Science Search
No.
Key words combinations Filters’ results
No filter Humans 10 years 5 years
1. CAD/CAM AND complete denture 107 N/A 100 75
2. #1 AND edentulous 33 N/A 29 21
3. # 2 AND maxilla 11 N/A 8 5
4. #2 AND conventional 9 N/A 9 5
5. # 2 AND removable 9 N/A 8 5
15
Table 5. Search strategy
Table 6. Search strategy
N/A, not applicable
After searching for all the articles on the five databases, reference lists of the selected articles were manually searched. This is to ensure that no important articles have been missed.
Date: 22.10.2017 Database: Scopus Search
No.
Key words combinations Filters’ results
No filter Humans Human +10 years Human +5 years
1. CAD/CAM AND complete denture 147 99 92 55
2. #1 AND edentulous 67 55 54 30
3. # 2 AND maxilla 18 18 14 7
4. #2 AND conventional 13 10 9 6
5. # 2 AND removable 15 14 11 4
6. # 2 AND fabrication 27 22 20 11
Date: 22.10.2017 Database: Cochrane Library Search
No.
Key words combinations Filters’ results
No filter Humans 10 years 5 years
1. CAD/CAM AND complete denture 10 N/A 10 8
2. #1 AND edentulous 8 N/A 8 6
3. # 2 AND maxilla 2 N/A 2 2
4. #2 AND conventional 5 N/A 5 4
5. # 2 AND removable 1 N/A 1 0
16
1.4 Study Selection
The preliminary electric search of the five databases revealed 1552 articles. After applying three filters: “Humans”, “10 years” and “5 years” and a combination of at least three key words, the resulted records were 714. During the review of the714 articles recorded after using keyword combinations and three filters, 283 duplicates were sorted out. The inclusion/exclusion criteria are then followed and of the 431 articles, 247 were excluded at the title level, 132 were excluded at the abstract level and 4 were sorted out because they were in languages other than English. The
remaining 48 articles were read as full text for eligibility, where another 5 articles, which were clinical reports, 10 articles, which were summaries, 5 articles, which were reviews, 11 articles, which were of another study design, as well as 12 articles, which included studies not comparing the two modalities of fabrication, were excluded. See flow chart below (Fig. 1).
17 Fig.1 Flowchart of selection process
a
PRISMA 2009
Flow Diagram
Records identified through searching databases Pubmed, ScienceDirect, Web of Science,
Scopus and Cochrane Library (n= 1552) Screening Included Eligibility Identificatio n
Additional records identified through other sources
(n = (0)
Records after using at least three keywords AND “Humans” AND “10 years” AND “5 years” filters
(n = 714 ) Records screened (n = 431 ) Records excluded at Title = 247 Abstract = 132 Language other than English =
4 (n = 383)
Full-text articles assessed for eligibility
(n = 48)
Full-text articles excluded: 1. Clinical reports (5) 2. Summaries (10) 3. Article review (5) 4. Study design (11) 5. Studies not comparing the two modalities of fabrication (12) (n=43) Studies included in qualitative synthesis (n = 5) Duplicates removed (n = 283 )
18
1.5 Quality and risk of bias assessment for the included studies
The remaining 5 studies (Kattadiyil et al. [20]; Schwindling and Stober [19]; Saponaro et al. [5]; Al Helal et al. [18]; Inokoshi et al. [21], which were selected to be included in the systematic review analysis, were evaluated by using The Critical Appraisal Checklist, a study quality assessment tool described by the Joanna Briggs institute [22]. This checklist list consists of 10-questions, where each question is answered ‘Yes’, ‘No’, ‘Unclear’, and ‘N/A’ (Not applicable). The quality of the study included is determined by an overall score, which is summed up on the basis of how many questions were answered as ‘Yes’. The scores would have a range from 0-10, according to which the studies were categorized: high quality study, scores 7-10; medium quality study, scores 4-6; or low quality study, scores 0-3. Accordingly, the studies of Kattadiyil et al, Schwindling and Stober, Saponaro et al and Inokoshi et al were evaulated as high quality studies. While, the study of AlHelal et al was assessed as a medium quality study (Table 7).
Table 7. Critical appraisal checklist of Qualitative Evidence by Joanna Briggs Institute
N/A, not applicable.
Criteria Kattadiyil et al. [20] Schwindling and Stober [19] Saponaro et al. [5] Al Helal et al. [18] Inokoshi et al. [21]
1. There is congruity between the stated philosophical perspective and the research methodology.
Yes Yes Yes Unclear Yes
2. There is congruity between the research methodology and the research question or objectives.
Yes Yes Yes Yes Yes
3. There is congruity between the research methodology and the methods used to collect data.
Yes Yes Yes Yes Yes
4. There is congruity between the research methodology and the representation and analysis of data.
Yes Yes Yes Yes Yes
5. There is congruence between the research methodology and the interpretation of results.
Yes Yes Yes Yes Yes
6. There is a declaration of the researcher’s cultural or theoretical orientation.
No No Unclear N/A N/A
7. The influence of the researcher on the research, and vice versa, is addressed.
Unclear No Unclear N/A N/A
8. There is representation of participants and their voices. Yes Unclear Yes Yes Yes 9. There is ethical approval by an appropriate body. Yes Yes Yes Yes Yes 10.There is a relationship between the conclusions of the study
and the analysis or interpretation of the data.
Yes Yes Yes Yes Yes
Total score 8 7 8 6 8
19 As for the risk of bias assessment, the articles were further reviewed thoroughly and assessed by The Cochrane recommendations for systematic reviews of interventions by Higgins and Green [23]. Seven key domains were included when evaluting each study (Table 8).
The following criteria were used to categorize the included studies for risk of bias: a study considered of unclear risk of bias if one or more key domains were assessed as an unclear risk of bias; a study considered at low risk of bias if all key domains were assessed as a low risk of bias; a study considered of high risk of bias if one or more key domains were assessed as a high risk of bias. Hence, two studies were found of high risk of bias (Kattadiyil et al and Saponaro et al), two studies were found of unclear risk of bias (Schwindling and Stober, and AlHelal et al) and one study presented a low risk of bais (Table 8).
Table 8. Risk of bias in the included studies
Domain Kattadiyil et al. [20] Schwindling and Stober [19] Saponaro et al. [5] Al Helal et al. [18] Inokoshi et al. [21]
1. Random sequence generation Low risk Unclear Unclear Unclear Low risk 2. Allocation concealment Low rsik Unclear Unclear Unclear Low risk 3. Blinding of participants and personnel High risk Low risk High risk Low risk Low risk 4. Blinding of outcome assessment Low risk Low risk High risk Low risk Low risk 5.Incomplete outcome data Low risk Low risk High risk Low risk Low risk 6.Selective reporting Low risk Low risk High risk Low risk Low risk
7. Other bias Low risk Unclear High risk Low risk Low risk
Risk of bias level High risk of bias Unclear risk of bias High Risk of bias Unclear risk of bias Low risk of bias
20
2. SYSTEMIZATION AND ANALYSIS OF DATA
2.1 Results
Data extraction. The studies that met the inclusion criteria and proven eligibility were submitted for data extraction. By the employment of a pre-defined data extraction form based on Cochrane, information about the study design, individual/sample description, results, complications as well as other significant characteristics were extracted and recorded.
The selected review articles with their methods, results are summarized in (Table 9).
2.1.1 Descriptive results
A total of 100 participants, for whom digital and conventional CRDPs were fabricated, were evaluated in the 5 reviewed studies of this systematic review. Two prospective clinical studies compared the technique efficacy between the digital and conventional CRDPs on both maxillary and mandibular edentulous dental arches [20] and [19]. The remaining three studies made the comparison only on the edentulous maxilla [5], [18] and [21].
Higher preference to the digital than conventional CRPDs with regard to denture stability, retention and fit, chewing efficiency and comfort was expressed by the participants in four studies, [20], [5], [18] and [19]. No significant difference between conventional and digital CDs with regard to esthetics and phonetics/speech was shown by 3 studies, [19], [20] and [21].
One study, Inokoshi et al. [21] showed no significant difference regarding the denture design, stability, comfort of the CRDPs fabricated by the 3D printing (RP) and conventional methods according to patient rating scores, but significantly higher prosthodontists’ scores for esthetics with the conventional method.
Patient satisfaction and preference was reported in three studies. In Saponaro et al.[5], kattadiyil et al.[20] studies, participants showed higher satisfaction with digital CRDPs. However, in the study of Inokoshi et al.[21] an equal satisfaction and preference for 3D printing (RP) and conventional methods was shown by the participants and prosthodontists’ rating scores.
According to the studies of Kattadiyil et al. [20] and Inokoshi et al. [21], less fabrication time and higher technique accuracy were offered by the digital method compared to the conventional one. Schwindling and Stober study [19], on the other hand, reported longer working time for the digital procedure.
Complications and problems encountered during the CRDPs fabrication by the digital method were also reported in the studies of Schwindling and Stober [19], Inokoshi et al.[21], and Kattadiyil et al.[20] (Table 9).
21
Table 9. Systematic review: characteristics of included studies with results: digital maxillary CRDPs in comparison to conventional maxillary CRDPs Author/ Year Study design Number (N) of individuals and description
Follow up Rating Scale /Questionnaire type Jaw to which CRDP is fabricated CRDPFabrication technique compared
Results Reported complications / problems Al Helal et al.[18] Clinical prospec-tive trial N=20 (11 men and 9 women, average of 68.20 ±7.27 years of age). N. Digital CD =10, N. Conventional CD = 10.
N/A N/A Max. CAD-CAM milled vs.
Conventional (Heat polymerized acrylic resin denture)
-Significant increase in retention for digital milled denture base (average 74.14±32.56 N) compared to conventional one (average 54.23 ±27.36 N), (p<. 001),
-Higher dimensional stability offered by milled denturebase,
-Improved fit wiht milled dentures.
Non-reported Kattadiyil et al. [20] Clinical prospective study N=15 (11 men and 4 women, average 55 years of age). N. Digital CD =15, N. Conventional CD = 15. 1 week for each CD fabricated by conventional/ Digital - A 5- point Likert Scale - Patient satisfaction questionnaire Max. / Mand. Digitally milled vs. Conventional (lost wax technique and heat-polymerizing acrylic resin)
-Significantly higher average scores for stability, retention, fit as well as denture base contour/finish with digitally milled dentures,
-No significant difference between conventional and digital CDs with regard to centric relations, vertical dimension establishment, tooth arrangement, lip support, esthetics/teeth display and phonetics/speech, (p= 0.763),
-Significantly higher preference with digital CDs in respect to chewing efficiency, comfort and patient selection,
-Patient satisfaction higher for digital CDs. -Prosthodontists' preference: higher for digital CRDP,
- Efficiency of technique: 2-visit insertion appointments for digital CDs.
Complications were found in digital CD fabrication technique: 1.anterioropenocclusalrelationship wasresultedduring digital CRDPprocessing,
2. difficulty in interpreting the digital CD preview image by the prosthodontics students.
22 Author/ Year Study design Number (N) of individuals and description
Follow up Rating Scale /Questionnaire type Jaw to which CRDP is fabricated CRDP Fabrication technique compared
Results Reported complications /
problems Schwindl-ing and Stober [19] Clinical prospective study N=5 patients. N. Digital CD = 5, N. Conventional CD = 5.
N/A A 6-point scale Max. / Mand.
Digitally milled vs. Conventional (injection molding)
-Slightly superior retention (for maxilla) for milled (mean 1.4) compared to injection molded (mean 1.6) CDs,
-No difference between both CDs in respect to fit for maxilla, both had (mean 1.29) scores,
-Vertical dimension establishment is slightly superior with injection molded (mean 1.0) over milled CDs (mean 1.2),
-No difference for both CDs with regard to phonetics/speech as well as esthetics, both had (mean 2.0) scores,
- Efficiency of technique: mean number of clinical sessions were 5.4, instead of 4-visit fabrication protocol.
These problems with digital CD were reported:
1. Custom trays borders required extensive shortening (in 2 participants);
2. Insufficient vertical dimension after the preliminary recording of the VDO and VDR and needed correction in the 2nd clinical
session.
3. Several esthetic problems: -shifted midlines,
-deviation from interpupillary line or Camper plane,
-repositioning of single teeth.
Retrospecti ve survey study N=50 patients (25 women and 25 men mean of 62.64 years of age). N. Digital CD =50. Mean of 21 months A 10- item patient satisfaction questionnaire (Only 19 patients responded) Max. (13 patients) Digitally milled vs. Conventional technique
Among the 13 patients who received a new digital CD for maxilla:
1. Higher preference for the digital over conventional CD with regard to: - esthetics: 10/13 (78.95%) participants -easier maintenance: 9/13 (68.75%) participants,
- comfort: 9/13 (68.42%) participants, -speech and chewing ability improvement: 8/13 (57.89%) participants,
-fit during function: 7/13 (52.63%) participants,
2. Higher patient satisfaction for digital CDs: 10/13 (74%) participants.
Non-reported
Saponaro et al. [5]
23 Author/ Year Study design Number (N) of individuals and description
Follow up Rating Scale /Questionnaire type Jaw to which CRDP is fabricated CRDP Fabrication technique compared
Results Reported complications /
problems Inokoshi et al. [21] Clinical trial N=10 patients (mean age 78.1 years). N. Digital CD =10, N. Conventional CD = 10. N/A A 100-mm visual analogue scale (VAS) Max. /Mand. 3D printed (RP system) vs. Conventional technique
Patien Ratings scores:
-No significant difference between 3D printing (RP) and conventiona lmethods with respect to:
Esthetics (p=0.61), denture design (p=0.93), denture stability (p=0.68), denture comfort (p=0.86), or overall satisfaction (p=0.59).
Prosthodontist Ratings scores:
-Significantly higher ratings scores with the conventional method for denture esthetics and stability (p<0.05).
-Significantly higher scores with the 3D printing (RP) method for chair time: (p<0.01).
-No significant differences between the two methods for verifying jaw relationship records and overall satisfaction (p>0.05).
Techniqueaccuracy:
-Higher processing accuracy with 3D printing (RP) method.
Two problems with 3D printed CD were reported:
1. Poor stability of denture due to errors in the scanning process using CBCT.
2. A chair-side alteration of artificial teeth arrangement in the 3D printed (RP) dentures was problmatic.
CRDP, complete removable dental prosthesis; CAD-CAM, computer-aided design and computer-aided manufacturing; CD, complete denture; VDO, vertical dimension of occlusion; VDR, vertical dimension at rest; RP, rapid prototyping; 3D, three-dimensional; CBCT, cone-beam computed tomography.
24
3. DISCUSSION
An increased interest in the application of digital technology (computer-aided design/Computer-aided manufacture) in the fabrication of complete removable dental prostheses, as a potential alternative to the conventional complete denture, has recently been highlighted by scientific publications in the field of removable prosthodontics. Through identifing published studies that applied, compared or measured the results of the two digital and conventional modalities, the present systematic review aimed to compare the fabrication of maxillary digital and coventional full removable dental prostheses with regard to clinical outcomes in terms of technique efficiency (accuracy, retention and fit, time, speech and esthetics), patient satisfaction and fabrication complications.
Out of the 48 articles assessed for eligibility, 5 studies selected for anaylsis for results to be compared between the two, digital and conventional CD methods. Despite the limited number of the included studies, a comparsion was manageable and the outcomes measured were presented in Table 9.
The computer-engineered complete removble dental prosthesesas has been introduced in several reviews [9, 24, 25, 6] which focused mainly on addressing evolution or description of the this innovative technology. Howerver, the digital technique efficacy and its clinical outcomes comapred to the conventional methods have not been broadly reviewed [26, 27].
Regarding the process working time required for the production of the two types of prostheses by the digital and conventional methods, a notable variation has been reported. In their study which was performed in predoctoral setting under the faculty supervision to compare digital CDs and conventional CDs, Kattadiyil et al. [20] found that digital CDs were fabricated efficiently in 2- visit protocol. The study also reported a difference of clinical time, 205 minutes more for the
conventional than for digital dentures. Another study by Inokoshi et al. [21] revealed that
prosthodontists, who conducted a trial fabrication of complete dentures using rapid prototyping (3D printing) approach compared to a conventional method, showed significantly higher rating scores (p<0.01) of chair time for 3D printing method compared to conventional method. While the pilot clinical trial conducted by Schwindling and Stober [19] choose 4-step approach for the fabrication of digital CDs in comparison to conventional CDs. Their clinical trial reported a mean of 5.4 clinical sessions were required to fabricate the digital CDs instead of the 4-visit protocol. The extra clinical sessions were needed for the corrections and reassessment of several esthetic problems. The study also proposed that experienced users could perform their fabrication approach in a 3-step protocol.
25 The accuracy of complete dentures fabricated by the digital techniques as opposed to the
conventional ones was evaluated by several studies. Two in vitro studies [28, 8] previously
compared the digital and conventional fabrication techniques of CRDPs in order to determine which method yielded the most accurate denture. Goodacre et al. [28] revealed that CAD/CAM milling technique showed the most uniform distribution of adaptation, compred to the other 3, Pack and press, Pour and Injection molding tecniques when the techniques accuracy were evaluated with respect to fabrication distortion based on 5 location: Apex of denture border, 6 mm from denture border, crest of ridge, palate, posterior plalatal seal area.
On the hand, the results from the study of Srinivasan et al. [8] showed that the conventional CD group had higher adaptation than the CAD/CAM milled CD group when the accuracy of intaglio surface was examined. In addition, the study also reported that both conventional and CAD/CAM milling technique showed high accuracy in these areas (vestibular flange, palate, tuberosities, alveolar crest and posterior palatal seal area (A- line)).
In this review, Kattadiyil et al. [20] showed more accurate denture base contour/finish with digitally milled CDs than with conventionally fabricated CDs. Also, the clinical trial of Inokoshi et al. [21], in which 10 patients received one 3D printed and one conventionally fabricated CD each, showed higher processing accuracy with 3D printing technique using the stereolithography apparatus (SLA) compared to the conventional wax dentures technique. The results of deviation analysis for a
maxillary 3D printed denture showed -0.4 mm to 0.4 mm (mean -0.0051mm) deviation from the reference data.
Bae et al. [15] compared the additive and subtractive manufacturing of dental inlays specimens. They found that the specimens fabricated using the SLA method showed smallest deviation difference from the reference data compared to the significant differences observed for the wax specimens and zirconia specimens fabricated by subtractive method, wax (P =.021) and zirconia (P =.048). This indicates that additive manufacturing (3D printing) has higher technique accuracy compared to that of subtractive manufacturing and conventional method.
With respect to retention, fit and stability of complete dentures produced by the two compared fabrication techniques, multiple studies showed variable results with slight superiority of the digital CDs over conventional CDs. AlHelal et al. [18] and Kattdiyil et al. [20] clinical prospective studies reported a significant increase in retention, improved fit and higher dimensional stability offered by the digitally milled denture bases (p<. 001).
26 The cinical study of Schwindling and Stober [19] revealed slightly superior retention for maxillary milled compared to injection molded CDs, but no difference between both CDs in respect to fit for maxilla. Saponaro et al. [5] study showed that 7/13 (52.63%) participants expressed improved fit of their digital dentures during function.
This superior retention, fit and stability of digital CDs could be owing to the fact that these above mentioned studies used pre-polymerized acrylic resin blocks for producing digitally milled denture bases. These blocks help minimize the polymerization shrinkage of denture bases and hence improve adaptation characteristics. Al-Fouzan A et al. [10] reported that digitally milled denture bases, made from pre-polymerized acrylic resin materials, also offer less distortion and less porosity leading to minimal attachment of microorganisms.
Moreover, the difference in fit is in agreement with what has been found previously by the clinical study of Bidra et al. [9] and the in vitro studies of Goodacre et al. and McLaughlin et al. [28, 29]. However, the clinical trial of Inokoshi et al. [21], in which complete dentures were 3D printed using rapid prototyping (RP) system and compared with conventional complete denture method, showed that the 20 prosthodontists, who evaluated the RP and conventional dentures according to 100-mm Visual analogue scale (VAS), rated a significantly higher stability with conventional method than with RP method, (p<0.05).
Participant’s satisfaction and preferences were assessed in accordance to patient questionnaires or visual analog scales. Aspects such as prostheses selection, esthetics, speech and chewing
improvement, comfort during function and overall satisfaction were evaluated. The results from this review showed higher preference and satisfaction for the digital CDs [20, 5]. Also, the
prosthodontic students who performed the fabrication process both types of CRDPs expressed higher preference for the digital CRDP over the conventional CRDP with regard to simplicity of performance. They also highly preferred the digital CD as the method they would emplo y for their practice [20]. This can be owing to the fact that the digital CDs procedures are shorter and less invasive which make the treatment more comfortable for the patient and the clinician. Another important factor is that the lack of blinding of participants and personnel to the type of denture could have influenced their responses in favor of the new digital denture.
On the other hand, in the study of Inokoshi et al. [21], the 3D printed CD and the conventional ones were equally rated by the patients with respect to comfort and esthetics of denture, and overall satisfaction.
27 However, the prosthodontists, who performed the fabrication of the two types of dentures,
expressed similar preference for 3D printing and conventional methods and higher ratings for esthetics with the conventional method. The reason why the 3D printed dentures had inferior esthetics is because these trial dentures are fabricated with ultraviolt light curable resins. These utaviolet light curable resins lack gum colour appearance and they require further manual painting with prosthetic composite resins. The esthetics of 3D printed CDs will definitely be improved if new gum-coloured material is used.
Complications during the fabrication process of the digital CDs were reported in three studies [19, 20, 21]. In the studies of Kattadiyil et al. [20] and Schwindling and Stober [19], where digitally milled CDs were fabricated, some complications were encountered while establishing the vertical dimension at rest. Other complications were related to esthetics and problems with the display of the front teeth as well as difficulty in evaluating the digital CD images. This insufficiency in
vertical dimension establishment occurred due to clinician’s inadequate experience in working with the new digital system. Esthetic problems could possibly have occurred due to lack of laboratory experience with new devices. These complications can be corrected by enhancing the clinicians and laboratory staff training and ability to interpret and work on these new digital systems. Any minor esthetic problems can also be reassessed in additional clinical session.
Two complications were associated with fabricating complete dentures by the 3D printing method [21]. The first problem was an error in the CBCT scanning of wax dentures. This CBCT scanning error caused imprecision of digital image, which was transferred to CAD software for digital denture design, and hence led to poor stability of the fabricated definitive denture.
The second problem was the difficulty in altering artificial teeth arrangement in 3D printed dentures at the chair-side. This is because of the artificial teeth and the denture base are 3D printed as one unit, unlike the conventional dentures where changing the position of the artificial teeth is not difficult.
3.1 Limitation to this systematic review
Some key limitations to this review include insufficient number of clinical studies ,comparing the two digital and conventional methods of CD fabrications and their outcomes, published in the literature. 5 studies were included in this review. Thus, the comparison of the obtained results is based mainly on these few studies. Another limitation is that only 2 studies reported follow up time. One study had 21-months follow up period, while the other study had 1 week follow up time for each denture fabricated by digital and conventional methods.
28 The long-term outcomes are, accordingly, based on limited data. Studies with longer follow up time observing the results of the two compared types of complete dentures would be more interesting to draw solid conclusions. Moreover, the included sudies have variable methodologies, which do not allow the direct comparison of these varied studies’ results.
An aditional limitation is the sample size. The sample size of the reviewed studies varied from 5 to 50 individuals. Although this sample size is sufficient to observe significant results, a larger sample size would concretely aid in evaluating the effectivness of the two compared interventions as well as offer more power and generalizability.
Furthermore, several of the included studies failed to achieve an effective blinding of patients and prosthodontists to the methods as well as blinding of clinical outcomes evaluation of the produced prostheses. Hence, a bias might have been generated and led to altered responses of the participants in favor of the new innovative technology.
ACKNOWLEDGEMENS
I would like to express a profound gratitude to Dr. Rimants Ožiūnas for his positive attitude and continuous guidance during the process of this study.
Many thanks for my family and friends for their never-ending motivation and support through the whole course of study.
CONFLICT OF INTEREST
29
CONCLUSION
Based on the findings of this systematic review, the following conclusions can be drawn:
1. The digital CD fabrication technique offered improved chewing ability and comfort during function, and better working time efficiency. No significant difference was found between the conventional and digital CDs with regard to esthetics and speech. Higher patient preference and satisfaction, and higher prosthodontists’preference were expressed for the digital CDs.
2. Higher retention and fit offered by the digitally milled complete dentures than that of the conventional ones.
3. During production of the digital dental prostheses, few complications were encountered which were attributed to insufficient clinical or laboratory experience in working with the digital devices.
30
PRACTICAL RECOMMENDATIONS
After having read many articles regarding the digital fabrication of complete dentures, the following can be recommend:
1. It is better to scan the cast and definitve impression/wax rim of the edentulous arch to acquire a digital image for the digital design of the complete denture.
2. I think that intraoral scanning of the edentoulos ridges by using digital scanner is not reliable for the time being. The intraoral digital scanner has not been used to scan edentulous dental archs yet. When used to scan partially edentulous arches, such as Kennedy Class III, it succeded only to register the static soft tissue extention. The dynamic extention of the soft tissue, however, could not be registered by this scanner.
3. To improve the digital workflow of the denture manufacturing, these procedures can be recommended for dental practitioners:
a. Taking preliminary and functional impressions and making wax rims, to establish jaw relations, with the conventional techniques, and then processing the maxillary and mandibular complete denture using the digital technique. This process may minimze problems associated with occlusal vertical dimension (VDO) and vertical dimension at rest (VDR) establishment, lip supportand maxillary incisal edge position maintenance;
b. Fabricating of a trial denture for esthetic and fit evaluation before the definitve denture is produced, particularly in these digital denture systems, such as Avadent and Dentica systems, where the trial denture is not offered. This will help avoid any esthethic problems such as shifted midlines, deviation from interpupillary line or Camper plane, and
repositioning of single teeth. Esthetic trial placement will increase the clinical sessions but it will help reduce the post-placement adjustments sessions.
c. Enhancing the clinical experince of the clinicians and laboratory technicians who will use the digital technology in their practice to overcome any difficulties associated with
following the manufacturer’s protocols of impressions taking, VDO and VDR establishing , and difficulties in interpretingthe digital CD preview images;
d. Validating the currently available complete denture digital systems through conducting proper clinical and laboratory studies and rule out any shortcomings for improvements; e. Active comunication and continuous feedback between the clinicians and the manufacturer
31
REFERENCES
1. Fenlon MR , Sherriff M. An investigation of factors influencing patients’ satisfaction with new complete dentures using structural equation modelling. J Dent 2008; 36(6): 427-434. 2. Divaris K, Ntounis A, Marinis A, Polyzois G, Polychronopoulou A. Loss of natural
dentition: multi-level effects among a geriatric.Gerodontology 2010; 29: e192-9.
3. Cooper FL, The Current and Future Treatment of Edentulism. J Prosthodont 2009;18: 116-122.
4. Saponaro PC, Yilmaz B, Johnston W, Heshmati RH, McGlumphy EA. Evaluation of patient experience and satisfaction with CADCAM- fabricated complete dentures: A retrospective survey study. J Prosthet Dent 2016; 116(4): 524-8.
5. Wimmer T , Gallus K, Eichberger M , Stawarczyk B. Complete denture fabrication supported by CAD/CAM. J Prosthet Dent 2016; 115(5): 541-6
6. Han W, Li Y , Zhang Y, lv Y, Zhang Y, Hu P, Liu H, Ma Z, Shen Y. Design and fabrication of complete dentures using CAD/CAM technology. Medicine (Baltimore). 2017; 96(1): e5435.
7. Srinivasan M , Cantin Y, Mehl A, Gjengedal H, Müller F, Schimmel M. CAD/CAM milled removable complete dentures: an in vitro evaluation of trueness. Clin Oral Invest 2017; 21:2007–19.
8. Bidra AS, Taylor TD, Agar JR. Computer-aided technology for fabricating complete
denture: systematic review of historical background, current status and future perspectives. J Prosthet Dent. 2013; 109(6): 361-6.
9. Al-Fouzan AF, Al-mejradLA,Albarrag AM. Adherence of Candida to complete denture surfacesin vitro: a comparisonofconventional and CAD/CAM completedentures. J AdvProsthodont 2017;9:402-8.
10. Zembic A, Wismeijer D. Patient-reported outcomes of maxillary implant-supported
overdentures compared with conventional dentures. Clin Oral Implants Res. 2014; 25: 441-50.
11. Almufleh B, Emami E, Alageel O, de Melo F, Seng F, Caron E, Nader SA, Al-Hashedi A, Albuquerque R, Feine J, Tamimi F. Patient satisfaction with laser-sintered removable partial dentures: A crossover pilot clinical trial. J Prosthet Dent 2017; 1-9 (article in press).
12. Barzanchi A, Li KC, Al-Amleh B, Lyons K, Waddell JN. Additive technology: update on current materials and applications in dentistry. J Prosthodont 2017; 26(2): 156-163.
32 13. Bilgin MS, Baytaroglu EN, Erdem A, Dilber E. A review of computer –aided
design/computer –aided manufature techniques for removable denture fabrication. Eur J Dent 2016; 10 (2): 286-291.
14. Bae EJ, Jeong ID, Kim WC, Kim JH. A comparative study of additive and subtractive manufacturing for dental restorations. J Prosthet Dent 2017; 118 (2): 187-193.
15. Dawood A, Marti BM, Jackson VS, Darwood A. 3D printing in dentistry. Br Dent J 2015; 219 (11): 521-9.
16. Kattadiyil MT, Goodacre CJ, Baba NZ. CAD/CAM complete dentures: a review of two commercial fabrication systems. J Calif Dent Assoc 2013; 41: 407-16.
17. Alghazzawi TF. Advancements in CAD/CAM technology: options for practical implementation. J Prosthodont Res 2016; 60: 72-84.
18. AlHelal A, AlRumaih HS, Kattadiyil MT, Baba NZ, Goodacre CJ. Comparison of retention between maxillary milled and conventional denture bases: a clinical study. J Prosthet Dent 2016; 117(2): 233-8.
19. Schwindling FS, Stober T. Acomparison of two techniques for the fabrication of complete removable dental prostheses: a pilot clinical study. J Prosthet Dent 2016; 116(5): 756-763 20. Kattadiyil MT, Jekki R, Goodacre CJ, Baba NZ. Comparison of treatment outcomes in
digital and conventional complete removable dental prosthesis fabrications in a predoctoral setting. J Prosthet Dent 2015; 114 (6): 818-825.
21. Inokoshi M, Kanazawa M, Minakuchi S. Evaluation of a complete denture trial method applying rapid prototyping. Dent Mater J 2012; 31(1): 40–46.
22. The Joanna Briggs Institute, The Joanna Briggs Institute Reviewers’ Manual, The Joanna Briggs Institute, Adelaide (Australia), 2014.
23. Higgins JPT, Green S. Cochrane handbook for systematic reviews of interventions Version 5.1.0. The Cochrane Collaboration, 2011. Available at:
http://training.cochrane.org/handbook.
24. Bilgin MS, Erdem A, Aglarci OS, Dilber E. Fabricating Complete Dentures with CAD/CAM and RP Technologies. J Prosthdont 2015; 24(7):576-9.
25. Goodacre CJ, Garbacea A, Naylor WP, Daher T , Marchack CB , Lowry J. CAD/CAM fabricated complete dentures: concepts and clinical methods of obtaining required morphological data. J Prosthet Dent 2012; 107(1): 34-46.
26. Kattadiyil MT, AlHelal A. An update on computer-engineered complete dentures: a systematic review on clinical outcomes. J Prosthet Dent 2016; 117(4): 478-485.
33 27. Gallardo YR, Bohner L, Tortamano P, Pigozzo MN, Lagana DC, Sesma N. Patient outcomes
and procedure working time for digital versus conventional impressions:a systematic review. J Prosthet Dent 2018; 119(2): 214-9.
28. Goodacre BJ, Goodacre CJ, Baba NZ, Kattadiyil MT. Copmarison of denture base adaptation between CAD-CAM and conventional fabrication techniques. J Prosthet Dent 2016; 116(2): 249-256
29. McLaughlin JB, Ramos VJ, Dickinson DP. Comparison of fit of denture fabricated by traditional techniques versus CAD/CAM technology. The American College of Prosthodontics. J Prosthodont 2017; 00: 1-8.
34
ANNEXES
Annex 1. Scheme of complete removable dental prostheses’ fabrication steps by Additive manufacturing (3D printing method).
Fabrication steps of CD by additive manufacturing (3D printing):
Made by conventional method
CD, complete denture; CBCT, cone beam computer tomography; DICOM, digital image and communication in medicine viewer; CT, computer tomography; 3D, three-dimensional; STL, standard triangulated language; CAD, computer-aided design; RP, rapid prototyping.
Edentulous arch functional impression made
Wax denture made and jaw relations established
Wax denture scanning with 3D scanner
Wax denture scanning with CBCT
CT images imported to DICOM viewer
CT images reconstruction and transference into 3D images
3D images imported into data workstation as STL files
CAD software: denture 3D images are designed
Trial denture fabricated by RP machine according to the designed denture 3D images
35 Annex 2. Scheme of complete removable dental prostheses’ fabrication steps by milling
manufacturing.
Fabrication steps of complete denture by milling manufacturing:
Using digital system kit 1 Using Conventional method
Laboratory Laboratory
1 Digital denture systems provide kits that contain impression materials, a set of trays used for the impression recording of maxillary and mandibular edentulous archs, and special trays used for establishing jaw relations, proper upper lip support and determing maxillary anterior teeth position.
Edentulous arch conventional impression made.
-Wax denture made and jaw relations established, - Teeth selected.
Wax denture assembly sent to laboratory.
Edentulous arch impression recorded
-Jaw relations established - Teeth selected.
Final impression assembly sent to laboratory.
-Final impression /wax denture assembly is laser scanned, -Digital denture image is created,
-Digital denture borders are marked using computer-aided design (CAD) software,
-Teeth are virtually set into proper occlusion, -Digital denture base morphology is established.
Digital preview of the virtual denture is sent to dentist for inspection.
-Denture base and teeth socket are milled, -Teeth are bonded in position.
-Final prosthesis is delivered,
36 EVALUATION FORM OF THE MASTER’S THESIS
FOR THE MEMBER OF DEFENCE COMMITTEE
Graduate student ___________________________________________________________________, of the year ______, and the group _____ of the integrated study programme of Odontology
Master’s Thesis title: ………...……….………...………… ………...….………...……...
No. MT evaluation aspects Evaluation
Yes Partially No 1 Has the student’s presentation lasted for more than 10 minutes?
2 Has the student presented the main problem of the Master’s thesis, its aim and tasks?
3 Has the student provided information on research methodology and main research instruments?
4 Has the student presented the received results comprehensively? 5 Have the visual aids been informative and easy to understand? 6 Has the logical sequence of report been observed?
7 Have the conclusions been presented? Are they resulting from the results? 8 Have the practical recommendations been presented?
9 Have the questions of the reviewer and commission’s members been answered correctly and thoroughly?
10 Is the Master’s thesis in compliance with the essence of the selected study programme?
Remarks of the member of evaluation committee of Master’s Thesis
______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ Evaluation of the Master’s Thesis
_____________________________________________________________________________
Member of the MT evaluation committee:
_________________________ ___________________________ ____________________
