Attachment Retained Tooth Supported Overdenture: A Case Series on Access Post Overdentures.

According to GPT, Overdenture is a removable partial or complete denture that covers and rests on one or more remaining natural teeth, roots, and/or dental implants; a dental prosthesis that covers and is partially supported by natural teeth, tooth roots, and/or dental implants. It is also called as overlay denture, overlay prosthesis and superimposed prosthesis.

The focus of preventive prosthodontics is on any intervention that can defer or avoid future prosthodontic difficulties, and overdentures play a significant role as a preventive therapy option.¹ The most depressing sequel is the loss of the patient’s self-confidence. A complete denture patient experiences a series of events including the loss of discrete tooth proprioception, progressive loss of alveolar bone, transfer of all occlusal forces from the teeth to the oral mucosa, and loss of alveolar bone. An overdenture improves denture foundation area, slows the process of resorption, and boosts masticatory efficiency.^2,3 The presence of periodontium in tooth supported Overdenture plays an important role of shock absorber, allows physiologic tooth mobility, elastic modulus of teeth closer to bone, functional stimulus for bone preservation, as compared to implant over denture.

For Overdenture fabrication if few firm teeth are present in compromised dentition, they can be used as abutments. In a 4 years study by Renner et al., it was found that 50% of the roots used as Overdenture abutments remained immobile.^4-6 The current paper describes two case reports on attachment overdentures that help restoring the patient’s dentition and also preserves.

Case Report 1:

A forty-one-year-old male reported to the Department of Prosthodontics and Crown & Bridge, with chief complaint of difficulty in chewing and unpleasant appearance since one month. Patient gave a history of blow to the face during a fight which led to extraction of multiple teeth in the mouth two weeks ago. On examination, the patient had a completely edentulous maxilla and a mandible with only two canines present (Fig. 1). the remaining natural teeth in the mouth.

On radiographic examination, the alveolar bone support and crown-root ratio was adequate and hence the patient was presented with an option for tooth supported overdenture. Patient was presented with fixed options using dental implants; however, the patient did not agree to the same due to financial constraints. Preliminary impressions were made for the maxillary arch in medium-fusing impression compound and for the mandibular arch in irreversible hydrocolloid. A tentative jaw relation was carried out to aid in planning the type of overdenture. Diagnostic mounting revealed adequate inter- arch distance for necessary components and aesthetic and functional placement of acrylic teeth. Treatment protocol was planned which involved three phases: Phase 1: Endodontic treatment of 33 and 43, Phase 2: Prosthodontic rehabilitation. The treatment plan was explained to the patient and an informed consent was obtained from the patient.

Intentional root canal treatment was carried out with 33 and 43. Following the endodontic therapy, the mandibular canines were prepared to receive the attachment. The tooth was prepared to around 1mm above the gingival edge. With 3-5mm of gutta percha remaining, post length was measured against an undistorted intraoral peri-apical radiograph. Using a Peeso reamer, gutta percha was extracted (No. 3 Peeso reamer for Red primary reamer, No. 4 Peeso reamer for Blue primary reamer and No. 5 Peeso reamer for Green primary reamer). The entire length of the post was prepared using the primary reamer. Preparations for the second tier and flange were made using a countersink drill. To assess how well access posts from Essential Dental System (EDS) (Fig. 2), a trial insert was conducted.

Apical end of post was trimmed to modify length, ensuring that flange and second tier were fully seated. The canal was dried using paper points. Using lentulo-spiral, the canal was etched and luted with resin cement.

The post was inserted into the canal and covered with resin cement.7 Excess cement was removed. (Fig. 3).

Primary impression was made with medium-fusing impression compound for the maxilla and for the mandible in irreversible hydrocolloid and a custom tray was fabricated. Secondary impressions were made with low-fusing impression compound and zinc oxide eugenol (Fig. 4).

Jaw relations were recorded and teeth arrangement was done. Try-in was done and the denture was processed in a conventional manner. (Fig. 5)

Rubber bands were placed to cover the height of contour of the ball of post. The nylon female caps were placed on ball of post above the rubber bands. Marking paste was placed on the cap and denture seated. Denture was removed, relieved in the area of marking paste to make space for nylon cap. Pink cold cure acrylic resin was placed in the relieved area. Denture was seated and patient was instructed to close in centric occlusion. A glove piece was used to prevent the direct contact of the resin with the mucosa to prevent any damage. After resin was set, denture was removed with pick up attachment cap housed in the intaglio surface of the denture. Rubber bands were removed & flash was trimmed. (Fig. 6).

Additional relief was provided at the marginal gingival area to prevent soreness of tissues.8 Post operative extra oral photograph of the patient can be seen in Fig. 7.

Case Report 2:

A forty-seven-year-old male reported to the Department of Prosthodontics and Crown & Bridge, with chief complaint of broken dentures. Patient reported history of broken dentures and coping with mandibular canine. On examination, teeth present were 33, 43, 37 and 47. 37 and 47 has mesial rest seat and the previous denture had a clasp arm extension bilaterally around the mandibular molars. The patient’s current prosthesis was used to evaluate the inter- arch distance and jaw relation. On radiographic examination, 33, 43, 47 and 37 had adequate bone support and crown-root ratio. The patient was provided with an option for EDS attachment overdenture and a metal base denture for the mandibular and maxillary arch to prevent future fractures of the prosthesis.

Previous coping from 33 was removed and post space preparation was done for the EDS attachment placement. EDS attachment was cemented in the similar manner as the previous case. The primary impression was in impression compound and irreversible hydrocolloid for maxilla and mandible, respectively. Final impression was made in low-fusing impression  compound and zinc-oxide eugenol paste (Fig. 8).

Jaw relations were recorded and teeth arrangement was done. Try-in was done and the denture was processed in a conventional manner; however, the dentures were processed with a metal base framework (Fig. 9).

Post operative photograph of the patient can be seen in Fig 11.

DISCUSSION

The focus of preventive prosthodontics is on any intervention that can postpone or prevent issues in the future. According to DeVan golden statement: “Perpetual preservation of what remains is more important than the meticulous replacement”. Remaining hard and soft tissues must be preserved for the overdenture’s basic principle to work. Tallgren came to the conclusion that conventional dentures caused anterior mandible height to resorb four times more quickly than maxillary ridge.⁹ A five-year study found that keeping the mandibular canines for overdentures helped to preserve the alveolar bone.⁶ The chewing efficiency of patients with overdentures was one-third higher than that of patients with complete dentures. The selection of the appropriate attachments for the given case will determine whether the overdenture treatment is successful. Based on the quantity of buccolingual and interarch space, the amount of bone support, the opposing dentition, clinical experience, individual preferences, maintenance issues, and cost, attachments are chosen.¹⁰

Access posts are the clinically easy to place and have added benefit of easy retrieval. The ball and socket attachment can be put into the denture without the help of a lab and is patient-friendly.¹⁰ The minimal male attachment head reduces the quantity of denture material that must be taken out. The attachment’s small head reduces the quantity of material that must be removed from the denture. The nylon cap has a retention of 3-5 pounds. The technical work required is modest and may be done at the patient’s side, making it cost effective. The flange and second layer of the access post overdenture distribute functional stresses and avoid “bottoming out,” eliminating the significant apical stresses under function that are seen in other passive posts. Furthermore, as described in case report 2, overdenture frameworks can be casted in metal bases which would help counter high occlusal forces, prevent frequent fractures and aid in easy repair.^11,12

The demerits of over dentures treatment pertain at meticulous oral hygiene in order to prevent caries and periodontal disease.¹³ The over-denture tends to be bulkier and overcontoured encroachment of inter-occlusal distance is another disadvantage. This treatment modality is an expensive approach with frequent recall check-ups of the patient than a conventional removable complete denture.¹⁴ Overdenture with attachments can redirect occlusal forces away from weak supporting abutments and onto a soft tissue or redirect occlusal forces toward stronger abutments thereby resulting in superior retention. Attachments are often used in Overdenture construction by either connecting the attachments to cast abutment copings or intra-radicularly Overdentures require careful assessment of vertical space. There must be sufficient room for the possible attachments, together with an adequate thickness of denture base material and artificial teeth, all this without jeopardizing the strength of the denture.¹⁵

Overdentures have gained popularity since the development of osseointegrated implants, however not many patients can afford the high cost of care. Although it is a viable alternative, its full potential is not frequently utilized. Dental treatment planning and patient satisfaction will be expanded by using attachments in overdentures into routine dental practice.

CONCLUSION

The access post retained denture not only aids in achieving the overdenture’s main objectives, but it also functions as a passive post by offering the restoration’s required strength, retention, and stability. The periapical tissues are also accessible, as the name implies, and can be retreated if they become contaminated after treatment, offering a far more predictable overdenture therapeutic option.