SciELO - Scientific Electronic Library Online

 
vol.11 número2 índice de autoresíndice de assuntospesquisa de artigos
Home Pagelista alfabética de periódicos  

RSBO (Online)

versão On-line ISSN 1984-5685

RSBO (Online) vol.11 no.2 Joinville Abr./Jun. 2014

 

Literature Review Article

 

Relining of removable dentures: a literature review

 

 

Cinthia Sawamura Kubo I; Fabrício Reskalla Amaral I; Edson Alves de Campos I

I Department of Restorative Dentistry, School of Dentistry of Araraquara, Sao Paulo State University – Araraquara – SP – Brazil

Correspondence

 

 


ABSTRACT

Introduction: The alveolar bone resorption that occurs after tooth loss leads to maladaptation of prostheses over the mucosa, causing discomfort to the patient. However, these maladaptations can be solved by prosthesis relining. Objective: The aim of this study was to discuss based on the literature, the relining of complete and partial removable dentures. Literature review: Dentistry makes use of relining materials that can be either rigid or resilient, having a temporary or permanent characteristic. However, to obtain a satisfactory result, the knowledge of their indications, contraindications, advantages, disadvantages is required, in addition to the characteristics and types of materials. Patients should be aware of the importance of constant monitoring, or even the need to reline their dentures, as it is not possible to determine the biological tolerance of each individual. Conclusion: The installation and proservation phases become essential to minimize bone resorption, and also to achieve rehabilitative treatment success.

Keywords: denture; partial denture; reline materials; literature review.


 

 

Introduction

The alveolar bone resorption occurring after tooth loss has been classified as a chronic, progressive, and cumulative disease of bone repairing that can lead to maladaptations of the prostheses. It appears to be continuous over the life of totally-edentulous or partially-edentulous patients 30. In rehabilitative cases with complete and partial removable dentures, this resorption compromises the adaptation of the prostheses, many times also damaging the speech and mastication. Therefore, prosthesis relining is indispensable to recover the biomechanical properties and occlusion and to provide comfort to patient 19.

According to Silva et al. 29, when properly indicated and used, relining materials promote interesting final outcomes in relation to patient's comfort. Notwithstanding, the clinical effectiveness depends on the knowledge of its features, indications and properties, having a definitive or temporary characteristic 5. Prosthesis relining can be achieved through direct or indirect techniques; rigid or resilient materials especially made for this purpose 30,33,34.

Current studies have indicated an alternative method for the polishing of dentures 7, indicators of the measurement of bone resorption 20 and reduction of alveolar bone resorption 11. Although the prosthesis clinical success over time has been high, the continuous monitoring of the patient should be considered 3,22,33. Thus, the installation and monitoring are indispensable steps for the success of the rehabilitative treatment. Questions of the installation and monitoring of the prostheses have been raised because the latter are important to minimize bone resorption and consequently leading to rehabilitative treatment success. Therefore, it seems appropriate the conduction of a literature review to discuss the guidelines of complete and complete denture relining.

 

Literature review

Bone resorption

Bone resorption is the main cause of removable prosthesis maladaptations; however this latter may also occur due to failures in impression or acrylization during the prosthesis construction. Many factors may alter the balance between the process of bone formation and resorption. According to Baat et al. 10, the main factors related to the resorption intensity have been the edentulous period and the mechanical action on the mucosa. Aquino et al. 1 have also cited the time of prosthesis use, age, route of force transmission towards the alveolar bone, site of the edentulous area, antagonist arch, adaptation of the niche support and saddle extension, finding the mean maladaptation of the saddle base of removable partial dentures (RPD) of 0.27 mm at the period from 1 to 5 years of use. Among the systemic factors, the literature has reported the advanced age, low calcium ingestion, diabetes, osteoporosis, corticosteroids use and estrogen deficiency 10,11,24.

Alveolar bone resorpt ion (ABR) involves the chronic, progressive, and cumulative bone resorption process, so that the bone tissue undergoes an intermittent metabolic activity over life, resulting in the gain or loss of bone mass 27. Kliemann and Oliveira 19 emphasized the importance of RPD relining because even if the patient is undergoing resorption stability, due to a systemic disease the physiologic tolerance balance may be altered and functional forces become damaging.

Barbosa et al . 3 studied the cl inical procedures for the installation of complete dentures, highlighting the evaluation of the prosthesis edges and occlusal adjustment. The authors concluded that the continuous monitoring of the patient by the professional should be considered. The CD installation is an important procedure to aid in rehabilitative treatment predictability because it is not possible to determine the biological tolerance of each individual. The proper installation provides greater comfort and consequent ly a greater prosthesis acceptance. Some techniques have been employed to improve prosthesis stability. Barbosa et al. 4 considered that one of the limitations occurring due to resorption is the shallow labial vestibule, which may compromise the prosthesis stability at the impression act. Among the techniques of vest ibule deepening, vest ibuloplasty with secondary epithelialization is the one providing the most adequate outcome in addition to an advantageous procedure.

Oliveira et al. 24, by discussing on the osteoporosis manifestations, emphasized the importance of panoramic radiographs in the evaluation of the alteration rates of oral cavity, making possible to achieve a proper referral of the patients in addition to the access of bone quality. Telles 33 highlighted that patients rehabilitated through mucous-supported dentures should be annually monitored so that the levels of bone resorption and possible maladaptation of the base with the mucosa can be verified.

By relating bone resorption with the use of dentures, Kranjčić et al. 20 proposed as bone resorption indicators the measurement between the thickness of the RPD base and the space of interocclusal resting, before and after the relining of prostheses. The interocclusal resting space has been defined as the distance (in mm) between the maxillary and mandibular central incisors when the patient's mandible is at physiologic resting position. The results showed statistically significant differences between the measurements performed in the study.

Relining technique

Tamaki 32 defined the relining as the readjustment of the denture base by the addition of a new material amount, which is indicated: in cases of maladapted CD not responding to retention and stability tests at the delivery moment; or in cases after use they lost these properties. Notwithstanding, during the technique description through employing a surgical guide for alveolotomy, the author affirmed that relining is not necessary. Telles 33 indicated immediate CD relining at 3 to 6 months after its installation; in maladapted prosthesis due to residual edge resorption; for correcting maladaptation problems of new prosthesis base; and in prosthesis that will be used as templates for planning and installation of osseointegrated implants.

By considering removable partial dentures (RPD), Kliemann and Oliveira 19 has classified the relining regarding to procedure type (mediate and immediate); support type (tooth-supported and tooth-mucosa-supported); prosthesis treatment type (relining and rebasing). They considered the mediate better than immediate relining in relation to technique, durability, materials used, greater reproduction of details, adequate flow, and low porosity and it is commonly indicated in cases of free-end PRD.

Relining mamaterials

Rigid materials

Acrylic resins appear in Dentistry at middle 1930s to replace vulcanized rubber that although showing satisfactory physical and mechanical properties did not present good esthetic 26,28,29,33. Acrylic resins have been indicated for immediate and mediate relining, also for rebasing of maladapted prostheses not responding to the retention and stability tests at the delivery moment, and in case of property lost after sometime of use 9,32.

Silva 30 recommended as alternative for CD maladaptation the acrylic resin relining. The author assumption is based in a clinical case in which a considerable improve of patient's mastication and speech was seen. The author considered this a simple technique, at one stage, with excellent outcomes for the patient, also highlighting that relining would be contraindicated in cases of prostheses with great tooth wear or malpositioned teeth; premature contacts or interferences; patients exhibiting an inflamed or hyperplastic support mucosa; loss of vertical dimension greater than 3 mm or lack of interocclusal space.

The composition of acrylic resins for relining is an important factor to be analyzed. Urban et al. 34 evaluated the percentage of residual monomer within different brands and concluded that some of the most used resins exhibited high percentage of residual monomers that can compromise the mechanical properties and cause allergic reactions. By evaluating the cytotoxicity of three acrylic resins, Ebrahimi et al. 12 found that all tested resins exhibited a certain cytotoxicity degree and indicated to emerge the prostheses in water for 24 hours previous to their delivery.

The materials employed as prosthesis bases should show proper mechanical properties. Azevedo et al. 2 observed the hardness of three acrylic resins. The authors concluded that hardness increased during the dry storage period and after this, water immersion resulted in softening of the specimens generating significant hardness reduction. Acrylic resin hardness may cause discomfort, accordingly Eduardo 13 researched the tension behavior on support structures of CD finding that the specimens constructed in acrylic resin and resilient material (silicon) promoted a more comprehensive tension distribution and they were the base type more recommended for CD.

The shear bond strength of four rigid resins for relining was evaluated by Neppelenbroek et al. 23. The bond strength values of rigid relining resins were similar. Acrylic resin samples were polished conventionally at the laboratory or polished by using in-office polishing kits. It was found that this latter was an alternative and effective procedure when the laboratorial polishing was not applicable 7.

According to Silva et al. 28, many researches have been developed aiming to improve the acrylic resin characteristics, highlighting microwave polymerization. Its use has been described as an excellent method because these resins can be an important alternative for the faster and lower cost production of prostheses. Because of the good properties presented, Costa Junior et al. 8 concluded that microwave polymerization technique provides a decrease of the polymerization time, reducing the laboratorial working time. The pores within thermo-activated resin may hinder the esthetic and lead to fracture possibility and distortion of the prosthesis bases. By analyzing the acrylic resin polymerization with microwave oven on water immersion, Rossato et al. 26 found that there was no alteration on the resin porosity, with or without water immersion.

Currently, the acrylic resin is the most accepted material for relining because it is considered as adequate for readapting on oral cavity, without damaging the tissues. According to the manufacturers, these resins are definitive immediate reliners and did not require posterior replacement due to material degradation. I can be inferred that their properties are similar to those of the material used in the prosthesis base 9.

Resilient materials

Resilient materials can be used to stabilize the prosthesis and condition the mucosa. In cases of maladapted prostheses, these materials reduce inflammations and lesions and have been indicated for implanted-supported prostheses 13. According to Carvalho 6, chemically-activated resilient resins can be used as either temporary or permanent material, with advantage of enabling the best adaptation of patients to prostheses. Tissue conditioners are other option of temporary materials used in prosthesis relining after surgeries or to recover an irritated or inflamed tissue.

Many indications for the use of resilient materials have been cited, e.g., retentive areas, resorbed alveolar edges, alveolar crest areas, areas of compression relief, recently operated patients, patients presenting tooth development alterations or xerostomia, as reported by Carvalho 6, Eduardo 13 and Silva et al. 29. Bulad et al. 5 listed some limitations regarding the use of resilient materials: problems when the rigid base thickness is minimum; instability in water; porosity; discoloration caused by some cleaning methods; failure in the adhesion between the resilient and acrylic base; difficulty in finishing and polishing.

For soft tissue surgeries, Eduardo et al. 14 indicated the immediate relining through tissue conditioners. The authors affirmed to obtain a provisional prosthesis that was kept stable during all period of tissue recovering with satisfactory post-operative period, excellent clinical appearance and faster and painless recovering period.

By evaluating the influence of chemical disinfection and storage, permanent deformation and porosity of three resilient reliners, Goiato et al. 16 found that all resilient reliners underwent deformation, even when submitted to chemical disinfection. By assessing the microorganism presence on soft reliner surface, with or without glaze application, Goyatá et al. 18 concluded that glazed reliners showed smaller microorganism presence. Landa et al. 21 evaluated the influence of glaze application on the superficial roughness of three reliners. The authors observed that Soft Comfort Denso was the resilient reliner that presented the smallest alteration on the superficial roughness with and without glaze application.

The lack of retention and stability and prosthesis fracture has been the major causes of searching for treatment at dental offices 17. Both the repair and posterior relining promote stability and retention, giving more safeness and comfort, returning the function, speech and esthetics. Eduardo 13 emphasized that resilient materials have limited durability, fact also confirmed by Elsemann et al. 15.

Oliveira et al. 25 verified the effect of sealant application and storage time on the permanent deformation of a tissue conditioner (Coe Comfort-GC). The authors demonstrated that the studied conditioner showed longevity of at maximum one week, and after that it requires replacement, without advantages for sealant application. Silva et al. 29 affirmed that the use of resilient bases promoted interesting final outcomes regarding patient's comfort, but these materials can deteriorate within a short time period. The authors emphasized that clinical effectiveness depends on the knowledge of this characteristics, indications and properties. Patients submitted to this treatment should be aware of the need of constant monitoring or reliner replacement due to the material limitations.

 

Discussion

Many authors are unanimous in affirming that because of tooth and periodontal ligament loss, and consequently of the local stimulus acting on alveolar bone, such periodontosis and traumas, bone resorption is initiated 1,4,19. This seems to be continuous over edentulous or partially-edentulous patients' life and may cause the maladaptation of prostheses during speech and mastication 20,30.

The prosthesis can be relined by laboratorial or in-office procedures. Direct (immediate) relining does not require that the patient stays without the prosthesis. It is a simple technique that extends the usage time 23,30. On the other hand, indirect (mediate) relining consists in a laboratorial clinical procedure, generally employing the prosthesis itself as customized tray. Mediate is better than immediate relining due to its technique, durability, material employed, greater detail reproduction, proper flow and low porosity 19,33. Notwithstanding, the period that the patient is without the prosthesis and the laboratorial steps that may induce error have been cited as disadvantages 13,19,33. It is commonly indicated for free-end RPD, according to Kliemann and Oliveira 19, and complete dentures according Telles 33.

The relining materials should exhibited adequate properties, such as easy technique, high durability, good dimensional stability and detail reproduction, proper flow, and low porosity 19. Rigid compared with resilient resins have shown superior qualities, as greater color stability, lower porosities, lower heat releasing, and greater durability 30.

Self-curing acrylic resins have been the most accepted for relining because of the lower polymerization temperature, which is adequate for oral cavity without damaging the tissues 30,34. Also they show good resistance and acceptance by patients 13,25, resistance to abrasion, are impermeable to oral fluids 8 and have certain dimensional stability and esthetic feature 26. The application of resilient/soft materials for prosthesis relining has been researched aiming at the comfort and masticatory effectiveness. Soft liners, so-called resilient reliners, are a group of elastic materials that can be used either temporary or definitive, decreasing the impact of the masticatory force on the underlying mucosa 13,15,29.

Resin liners presenting polymethylmethacrylate causes an important irritation on oral mucosa 34. Additionally to the replacement of this component, the introduction of other monomers improved these materials, fact proved by Azevedo et al. 2 and Silva 30. Acrylic resins are commercially available in two flasks containing the polymer and monomer. The polymerization process, in which the monomers are converted into polymer is not complete, always resulting in residual monomer 15,16. Ebrahimi et al. 12 evaluated the cytotoxicity of three acrylic resins and found that all tested resins induced a certain cytotoxicity degree.

Resilient reliners do not exhibit a satisfactory longevity. Its use should be associated with a strict monitoring because of the resilient characteristic of the material may be lost over time 15,29. Additionally, frequent displacements between resilient reliners and the prosthesis base also decrease its useful lifetime 15,29,30. In an attempt to extend the softness and resilience and avoid porosity of tissue conditioners, Eduardo 13 and Eduardo et al. 14 indicated the immediate post-surgical relining and affirmed that the reliners can stay for 5 to 6 months, decreasing the costs and avoiding successive material changes.

According to Bulad et al. 5 and Silva et al. 29, resilient materials have some limitations regarding to its use, such as the instability in water, porosity, discoloration and difficulty of polishing. Some authors have recommended using as temporary material 14,18. In the study of Landa et al. 21 glaze application influenced on superficial roughness of reliners. Goyatá et al. 18 reported that it also decreased the accumulation of oral microorganisms.

Thus, regardless of the material choice, to perform an adequate relining, it is necessary that both oral cavity and the mucosa are at a good health state. Otherwise, the use of tissue conditioners or temporary materials is the most indicated 19. Patients should be aware that their prostheses will not last forever. Periodically, the degree of bone resorption, prosthesis adaptation, masticatory efficiency, and hygiene conditions should be assessed.

The literature has established that, except from immediate complete dentures requiring relining at a shorter time period 33, the mean period for periodical relining procedures is six years for a complete denture 22 and three years for removable partial prostheses 19. Although many prostheses are successfully for years, the continuous monitoring of the patient ought to be considered, because it is not possible to determine the biological tolerance of each individual 3,9,33. Therefore, both the installation and monitoring of removable prostheses are indispensable steps for rehabilitative treatment success.

 

Conclusion

Based on this literature review, it can be concluded that removable prosthesis relining should be performed from 1 to 4 months after tooth extractions, preferably through immediate relining technique and with self-curing acrylic resin. In-use removable prostheses should be relined from 1 to 5 years, preferably through mediate relining technique and with self-curing acrylic resin. It is worth emphasizing that to reach complete and partial prosthesis relining success, it is necessary the knowledge of the indications, contraindications, advantages, disadvantages, characteristics and types of relining materials.

 

References

1. Aquino AR, Barreto AO, de Aquino LM, Ferreira ÂM, Carreiro Ada F. Longitudinal clinical evaluation of undercut areas and rest seats of abutment teeth in removable partial denture treatment. J Prosthodont. 2011 Dec;20(8):639-42.         [ Links ]

2. Azevedo A, Machado AL, Vergani CE, Giampaolo ET, Pavarina AC. Hardness of denture base and hard chair-side reline acrylic resins. J Appl Oral Sci. 2005 Sep;13(3):291-5.

3. Barbosa DB, Barão VAR, Assunção WG, Gennari Filho H, Goiato MC. Instalação de prótese total: uma revisão de literatura. Rev Odontol UNESP. 2006;35(1):53-60.

4. Barbosa FQ, Rocha FS, Batista JD, Magalhães AEO, Zanetta-Barbosa D, Marquez IM. Aprofundamento de vestíbulo pela técnica de Kazanjian modificada: relato de caso. Rev Inpeo Odontol. 2008 Aug-Dec;2(2):1-56.

5. Bulad K, Taylor RL, Verran J, McCord JF. Colonization and penetration of denture soft lining materials by Candida albicans. Dent Mat. 2004 Feb;20(2):167-75.

6. Carvalho LPR. Soluções para quem perdeu (todos) os dentes. Rev APCD. 2001 Mar-Apr;55(2):73-81.

7. Chatzivasileiou K, Emmanouil I, Kotsiomiti E, Pissioti A. Polishing of denture base acrylic resin with chairside polishing kits: an SEM and surface soughness study. Int J Prosthodont. 2013 Jan-Feb;26(1):79-81.

8. Costa Junior HC, Zanetti RV, Junqueira JLC, Santos VMA. Análise de resinas acrílicas polimerizadas por energia de microondas em relação ao método convencional. Rev Gaúc Odontol. 2005 Oct-Dec;53(4):307-12.

9. Cucci AL, Vergani CE, Giampaolo ET, Pavarina AC, Bercial ME. Resinas para reembasamento imediato: resistência à tração e alongamento. Rev Odontol UNESP. 1998;27(1):299-309.

10. De Baat C, Kalk W, Van't Hof M. Factors connected with alveolar bone resorption among institutionalized elderly people. Community Dent Oral Epidemiol. 1993 Oct;21(5):317-20.

11. Deves C, de Assunção TM, Ducati RG, Campos MM, Basso LA, Santos DS et al. The transition state analog inhibitor of purine nucleoside phosphorylase (PNP) Immucillin-H arrests bone loss in rat periodontal disease models. Bone. 2013 Jan;52(1):167-75.

12. Ebrahimi SM, Vojdani M, Bahrani F. Evaluation of cellular toxicity of three denture base acrylic resins. J Dent. 2012 Dec;9(4):180-8.

13. Eduardo JVP. Materiais macios usados em base de prótese total para reembasamento direto e indireto. Rev APCD. 1997 Nov-Dec;51(6):531-3.

14. Eduardo JVP, Haypek P, Machado MSS. Cirurgia pré-protética utilizando laser de diodo associada a reembasamento com condicionador de tecidos: relato de caso clínico. Rev Bras Prot Clín Lab. 2003;5(27):396-401.

15. Elsemann RB, Santos VMA, Ishikiriama A, Zanetti RV, Zanetti AL. Reembasamento das próteses totais. Rev Gaúc Odontol. 2003 Oct;51(4):371-6.

16. Goiato MC, Guiotti MA, Ribeiro PP, Santos DM, Antenucci RMF. Materiais reembasadores: estudo da deformação inicial, permanente e porosidade. Ciências Odontol Bras. 2007 Jul-Sep;10(3):44-52.

17. Goyatá FR, Gonçalves PAM, Manta GF, Carvalheira TB, Ferreira NG. Reembasamento em prótese total: relato de caso clínico. Dental Scien Clin e Pesq Integ. 2009;393:39-46.

18. Goyatá FR, Gonçalves PAM, Bello RF, Ferreira NG, Ferreira TG, Coelho SM. Avaliação quantitativa de microrganismos orais em materiais reembasadores de prótese total. Int J Dent. 2009 Apr-Jun;8(2):79-81.

19. Kliemann C, Oliveira W. Manual de prótese parcial removível. 1. ed. Santos: Livraria; 2006.

20. Kranjčić J, Kostelić Stunić M, Celebić A, Komar D, Mehulić K, Vojvodić D. Denture relining as an indicator of residual ridge resorption. Med Glas Ljek Komore Zenicko-doboj Kantona. 2013 Feb;10(1):126-32.

21. Landa FV, Goyatá FR, Hespanhol FL, Dias AL, Cunha LG, Gonçalves PAM et al. Influência da aplicação do glaze na rugosidade superficial de três materiais reembasadores. Int J Dent. 2009 Jul-Sep;8(3):124-7.

22. Nakamae AEM, Cunha EF, Tamaki R, Guarnieri TC. Avaliação da retenção de próteses totais bimaxilares em função das características da área basal. RPG Rev Pós Grad. 2006;13(1):69-76.

23. Neppelenbroek KH, Pavarina AC, Gomes MN, Machado AL, Vergani CE. Bond strength of hard chairside reline resins to a rapid polymerizing denture base resin before and after thermal cycling. J Appl Oral Sci. 2006 Dec;14(6):436-42.

24. Oliveira LSAF, Neves FS, Torres MGG, Crusoé-Rebello IM, Campos PSF. Características radiográficas dos portadores de osteoporose e o papel do cirurgião-dentista no diagnóstico. Rev Ciênc Méd Biol. 2009 Jan-Apr;8(1):85-90.

25. Oliveira LV, Matta RVL, Mesquita MF, Henriques GHP, Consani RLX. Efeito da aplicação de selante e da armazenagem sobre a deformação permanente de um condicionador de tecidos. Rev Saú Com. 2008;4(2):97-104.

26. Rossato MB, Montagner H, Scheid PA, Burmann PA, Braun KO. Influência da imersão em água na porosidade de resina acrílica polimerizada por energia de microondas. Rev Odontol Ciênc. 2008;23(4):342-5.

27. Santiago JL, Marcucci M, Avolio G. Osteoporose e Odontologia. Rev Reg Araçatuba Assoc Paul Cir Dent. 2006;12:4-5.

28. Silva SMLM, Bindo MJF, Leão MP. O uso de energia de microondas para polimerização de resinas acrílicas. Rev Dens. 2006 May-Oct;14(1):12-21.

29. Silva AG, Seraidan PI, Jansen WC. Bases resilientes: uma revisão. Rev Odontol de Araçatuba. 2007 Sep-Dec;28(3):56-62.

30. Silva RJ. Reembasamento direto para prótese total: uma alternativa simples e eficiente – relato de caso clínico. Int J Dent. 2008 Jul-Sep;7(3):190-4.

31. Sverzut CE, Gabrielli MFR, Vieira EH, Sverzut AT. Avaliação radiográfica da altura mandibular anterior após vestibuloplastia por inversão de retalhos: estudo em humanos. Pesq Odontol Bras. 2001 Apr-Jun;15(2):133-7.

32. Tamaki T. Dentaduras completas. 4. ed. São Paulo: Sarvier; 1988.

33. Telles D. Prótese total – convencional e sobre implantes. 1. ed. São Paulo: Santos; 2009.

34. Urban VM, Machado AL, Vergani CE, Giampaolo ET, Pavarina AC, Almeida FG et al. Effect of water-bath post-polymerization on the mechanical properties, degree of conversion, and leaching of residual compounds of hard chairside reline resins. Dent Mat. 2009 May;25(5):662-71.

 

 

Corresponding author:
Cinthia Sawamura Kubo
Departamento de Odontologia Restauradora
Faculdade de Odontologia de Araraquara – Universidade Estadual Paulista Júlio de Mesquita Filho
Rua Humaitá, n. 1.680
CEP 14801-903 – Araraquara – SP – Brasil
E-mail: cinthiakubo@yahoo.com.br

 

 

Received for publication: June 26, 2013
Accepted for publication: November 12, 2013