Telescopic Crowns as Attachments for Implant Supported Restorations: A Case Series

TELESCOPIC CROWNS AS ATTACHMENTS FORIMPLANT SUPPORTED RESTORATIONS:A CASE SERIES

Oliver Hoffmann, Dr Med Dent,MS

Christian Beaumont, Dr Med DentDimitris N. Tatakis, DDS, PhDGregory-George Zafiropoulos,

Dr Med Dent

KEY WORDS

Dental implantsTelescopic crownsAttachmentsDentures

Oliver Hoffmann, Dr Med Dent, is anassistant professor in the Department ofPeriodontics, Loma Linda University,School of Dentistry, Loma Linda,CA 92350. Address correspondenceto Dr Hoffmann(e-mail: [email protected]).

Christian Beaumont, Dr Med Dent, isan oral surgeon at the ‘‘Blaues Haus’’Dental Institute in Dusseldorf, Germany.

Dimitris N. Tatakis, DDS, PhD, isa professor in the Section of Periodontology,College of Dentistry, The Ohio StateUniversity Health Sciences Center,Columbus.

Gregory-George Zafiropoulos, Dr MedDent, is an associate professor in theDepartment of Operative Dentistry andPeriodontology at the University of Mainz,Germany. He is also a periodontist at the‘‘Blaues Haus’’ Dental Institute inDusseldorf, Germany.

The use of dental implants to support mandibular or maxillary

overdentures is a widely used treatment modality. Advantages are an

increase in retention, an increase in chewing ability, and easy access for

oral hygiene procedures. While telescopic and conical crowns have

been used for decades to connect natural teeth to overdentures, not

many cases have been reported in the literature of telescopic crowns

placed on implants to support overdentures. This article describes

7 patients with overdentures supported by telescopic crowns who

received 65 implants (ITI Straumann). The cases presented in this

report have been in function for up to 4.5 years. During that time no

adverse events were reported. The use of telescopic crowns as

attachments for implant-supported overdentures may be a viable

treatment option.

INTRODUCTION

The use of telescopiccrowns on naturalteeth (ie, a doublecrown system inwhich an interiorcrown with a cylin-

drical shape is placed on thetooth to support a removablecrown), is a treatment conceptthat has been widely and suc-cessfully used to support den-tures since telescopic crownswere introduced in the 1970s.1–18

They allow for easy access fororal hygiene around the abut-ment teeth as well as easy han-dling of the overdenture.4 Thecomparatively high retention ob-tained leads to good mastication

and phonetics. Therefore, theyoften offer more advantages thanother types of attachments.4,6

Telescopic crowns also allowfor an overdenture design thatincludes teeth with questionablelong-term prognosis, leaving roomfor later tooth removal if neces-sary, while still guaranteeing suf-ficient support of the denture.4,6,11

The use of implant-supportedoverdentures is a treatment ap-proach with a very high long-term success rate.19–22 The use ofimplants to support overdenturesincreases patient comfort by im-proving retention and chewingability.

Compared to the use of fixed-implant–supported dentures, thistreatment modality often leads to

Journal of Oral Implantology 291

CLINICAL

an esthetically more pleasant re-sult, the best access for oral hy-giene, and allows for the useof a lower number of implants.Furthermore, the use of over-dentures, tooth- or implant-sup-ported, is often beneficial forphonetic reasons.10

Bar, ball, and magnetic attach-ments have been suggested toconnect the overdenture to theimplants.23–25 Contrary to theiruse on natural teeth, there arenot many reports in the literatureon the use of telescopic crownsfor the connection between im-plants and overdentures.

This article presents 7 cases ofthe use of telescopic crowns forthe support of overdentures ondental implants (Table 1).

MATERIAL AND METHODS

Patient population

Sixty-one implants were insertedin 7 adult patients (4 female and3 male; age range 38 to 62 years).All patients were free of anymedical conditions interferingwith implant treatment. Five(71.43%) patients were smokersand 2 (28.58%) were nonsmokers.All patients had been referredfrom general dentists and werenot previously treated for peri-odontal disease at the time of thefirst examination.

Examination

Each patient underwent a com-prehensive dental and periodon-tal examination. Periodontal chart-ing included documentation ofprobing depths, recessions, clini-cal attachment levels, bleedingon probing, tooth mobility, furca-tion involvement, and plaquescores. Periodontitis was diag-nosed in the presence of morethan 4 sites with clinical attach-ment loss exceeding 4 mm, radio-

graphic evidence of alveolarbone loss, and bleeding on prob-ing. Impressions for diagnosticcasts were taken and a panoramicradiograph was obtained. Castswere mounted on a semi-adjust-able articulator after face-bowtransfer and check-bite registra-tion. An occlusal analysis wasperformed, diagnostic wax-upswere prepared on the articulatedcasts, and restorative treatmentneeds determined. Once the re-storative and periodontal treat-ment plans were established,radiographic and surgical guideswere fabricated to facilitate im-plant placement. Table 1 showsthe patient treatment plan andtime schedule.

Periodontal treatment

Periodontal treatment, includingsurgical treatment if necessary,had been performed previouslyon all patients.

Implant selection

Unless outlined differently, cylin-drical screw implants with alarge-grit sandblasted and acid-etched surface and either a 1.8-mm or a 2.8-mm smooth neckwere used (ITI Straumann Stan-dard Plus with a 1.8-mm smoothneck; ITI Straumann Standardwith 2.8-mm smooth neck; Wal-denburg, Switzerland; Table 2aand b). Implant size was deter-mined based on assessment witha panoramic radiograph takenwith a radiographic stent in place,and a clinical examination.

Medication

Standard medication for all casesincluded diclofenac (Voltaren;Novartis Pharma, Nurnberg,Germany), a nonsteroidal anti-inflammatory drug, 100 mg oncea day for 4 days; clindamycin(Ratiopharm, Ulm/Donautal, Ger-many), a systemic antibiotic, 600

mg once a day for 6 days; and0.1% chlorhexidine rinses (Chlor-hexamed Fluid, GlaxoSmithKline,Buhl, Germany) twice a day. Med-ication was administered starting1 day before surgery.

Surgical protocols

Unless outlined differently forany individual case, procedureswere performed following theprotocols outlined below.

Implant placement

An intersulcular incision extend-ing to the first adjacent tooth oneach side was placed and a full-thickness flap was elevated.

Implant sites were preparedat 875 rpm using a 16:1 handpiece (Nouvag AG, Goldbach,Switzerland) and a microcom-puter-controlled surgical micromotor (micro-dispenser model7/8000, Nouvag).

Implants were inserted andtightened to a torque of 35 N witha hand ratchet (model 046.119/046.049; Straumann).

The surgical site was coveredwith a resorbable bilayer mem-brane (BioGide, Geistlich Bioma-terials, Wolhusen, Switzerland).

Socket preservation

If tooth extraction was necessaryin the area of implant placement,the indicated tooth was removedwith as little surgical trauma aspossible. Following curettage, theextraction socket was irrigated,and covered with a 25 3 30 mm,nonresorbable membrane (Cyto-plast Regentex GBR-200, Oral-tronics, Bremen, Germany). Mem-branes were removed after 4weeks.

Sinus augmentation

If necessary, sinus augmentationwas performed following a pre-viously described protocol.26 A

TELESCOPIC CROWNS

292 Vol. XXXII/No. Six/2006

1:1 mixture of bovine allograft(0.25-1 mm, 0.25 g; BioOss spon-giosa, Geistlich Biomaterials)and autogenous corticocancel-lous bone (harvested from theretromolar or chin area) was usedas the graft material. The accesswindow was covered with a re-sorbable barrier membrane (Bio-Gide, Geistlich Biomaterials). Themembrane was fixated with ab-sorbable pins (Resor Pins, Geist-lich Biomaterials).

Patients were instructed toavoid wearing any removabledentures for the first 2 weekspostoperatively. Postoperativefollow-up visits were scheduledat 1, 4, and 7 weeks.

Implant placement was per-formed 4 to 6 months after thesinus augmentation surgery orsimultaneously with the aug-mentation if the residual alveo-lar crest height exceeded 4mm.

Maintenance

Supportive periodontal therapywas performed every 4 months.At each appointment, pocketdepth (PD), clinical attachmentlevel (AL), bleeding on probing(BOP), and plaque accumulation(PI) were recorded at 4 sites ofeach implant.

AL was defined as the dis-tance in mm between the deepestpoint of the peri-implant area andthe smooth neck section of theimplant. Measurements were ob-tained by the use of a periodontalprobe (KM0805, Hu-Friedy, Lei-men, Germany).

Removal of soft and harddeposits around the implantsand natural teeth, as well asirrigation of the peri-implant areawith 0.1% chlorhexidine (Glaxo-SmithKline), was performed ateach visit; oral hygiene instruc-tions were also given.

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Oliver Hoffmann et al


Cases

Case I

A 50-year-old man presented inthe office for a complete oralrehabilitation. Clinical and radio-graphic evaluation revealed thatnone of the remaining teeth weresalvageable for either periodon-tal or restorative reasons. There-fore, the treatment plan includedthe extraction of all remainingteeth; fabrication of a completemaxillary denture; and an im-

plant retained, supported com-

plete denture for the mandible,

using telescopic crowns as

attachments.After the extraction of all

remaining teeth, provisional com-

plete dentures were delivered.

Five months later, 6 ITI implants

were placed in the mandible.

Four months later a complete

maxillary denture was delivered.

An implant-supported complete

mandibular denture using tele-

scopic crowns as attachments wasfabricated at the same time.

Case II

The 53-year-old woman was re-ferred for periodontal and im-plant treatment by her generaldentist. In the maxilla, only toothNo. 6 was remaining. This toothwas nonsalvageable.

Tooth No. 6 was extracted,and scaling and root planingwas performed in the mandibulardentition. The periodontal condi-

TABLE 2A

Diameter (in mm), length (in mm), and type,* of implants used in the maxilla

PatientNo. 1

(0 Implants)

PatientNo. 2

(8 Implants)

PatientNo. 3

(6 Implants)

PatientNo. 4

(2 Implants)

PatientNo. 5

(6 Implants)

PatientNo. 6

(8 Implants)

PatientNo. 7

(7 Implants)

#6 (04.1 mm,10 mm, RN)

#4 (4.1 mm,12 mm, RN, PLUS)

#6 (4.1 mm,12 mm, RN, PLUS)

#5 (4.1 mm,10 mm, RN, PLUS)

#8 (4.1 mm,10 mm, RN)

#8 (4.1 mm,10 mm, RN)

#5 (4.1 mm,10 mm, RN)

#6 (3.3 mm,12 mm, RN, PLUS)

#11 (4.1 mm,12 mm, RN, PLUS)

#6 (4.1 mm,12 mm, RN)

#6 (4.1 mm,10 mm, RN)

#6 (4.1 mm,12 mm, RN)

#4 (4.1 mm,10 mm, RN)

#7 (4.1 mm,12 mm, RN, PLUS)

#8 (4.1 mm,12 mm, RN)

#4 (4.8 mm,10 mm, RN)

#16 (4.8 mm,10 mm, WN)

#3 (4.1 mm,10 mm, RN)

#10 (4.1 mm,12 mm, RN, PLUS)

#9 (4.1 mm,12 mm, RN)

#3 (4.8 mm,10 mm, RN)

#9 (4.1 mm,10 mm, RN)

#11 (4.1 mm,10 mm, RN)

#11 (3.3 mm,12 mm, RN, PLUS)

#11 (4.1 mm,12 mm, RN)

#9 (4.1 mm,10 mm, RN)

#11 (4.1 mm,12 mm, RN)

#12 (4.1 mm,10 mm, RN)

#13 (4.1 mm,12 mm, RN, PLUS)

#12 (4.1 mm,10 mm, RN)

#11 (4.1 mm,10 mm, RN)

#12 (4.1 mm,10 mm, RN)

#13 (4.1 mm,10 mm, RN)

#13 (4.1 mm,10 mm, RN)

#14 (4.8 mm,8 mm, PLUS, WN)

#14 (4.1 mm,10 mm, RN)

#14 (4.8 mm,10 mm, RN)

*Types of Straumann ITI implants: RN indicates Regular Neck; WN, Wide Neck; NN, Narrow Neck. Standard implants wereused, unless otherwise specified (PLUS).

TABLE 2B

Diameter (in mm), length (in mm), and type,* of implants used in the mandible

PatientNo. 1

(6 implants)

PatientNo. 2

(0 Implants)

PatientNo. 3

(6 Implants)

PatientNo. 4

(6 Implants)

PatientNo. 5

(4 Implants)

PatientNo. 6

(6 Implants)

PatientNo. 7

(0 Implants)

#23 (4.1 mm,10 mm, RN)

#19 (4.8 mm,12 mm, WN, PLUS)

#19 (4.1 mm,12 mm, RN, PLUS)

#19 (4.1 mm,12 mm, RN)

#29 (3.3 mm,8 mm, RN, PLUS)

#22 (4.1 mm,10 mm, RN)

#20 (4.1 mm,12 mm, RN, PLUS)

#21 (4.1 mm,12 mm, RN, PLUS)

#23 (3.3 mm,12 mm, NN)

#28 (4.1 mm,12 mm, RN, PLUS)

#20 (3.3 mm,10 mm, RN)

#22 (3.3 mm,12 mm, RN, PLUS)

#24 (4.1 mm,12 mm, RN, PLUS)

#30 (4.1 mm,12 mm, RN, PLUS)

#26 (3.3 mm,12 mm, RN)

#26 (4.1 mm,10 mm, RN)

#27 (3.3 mm,12 mm, RN, PLUS)

#25 (4.1 mm,12 mm, RN, PLUS)

#26 (3.3 mm,12 mm, NN)

#24 (3.3 mm,12 mm, RN)

#27 (4.1 mm,10 mm, RN)

#29 (4.1 mm,12 mm, RN, PLUS)

#27 (4.1 mm,12 mm, RN, PLUS)

#22 (4.1 mm,12 mm, RN, PLUS)

#29 (3.3 mm,10 mm, RN)

#30 (4.8 mm,12 mm, WN, PLUS)

#30 (4.1 mm,12 mm, RN, PLUS)

#21 (4.1 mm,12 mm, RN, PLUS)

*Types of Straumann ITI implants: RN indicates Regular Neck; WN, Wide Neck; NN, Narrow Neck. Standard implants wereused, unless otherwise specified (PLUS).

TELESCOPIC CROWNS


tion appeared stable after theinitial treatment phase. No fur-ther periodontal treatment otherthan regular supportive therapywas necessary.

Four months after tooth ex-traction, a bilateral sinus augmen-tation procedure was performed.After a healing period of 8months, 8 ITI implants wereplaced in the maxilla. Six monthsafter insertion, the implants wereloaded with a telescopic crownretained removable denture. Thedenture was designed with a freepalate (horseshoe-shape).

Case III

A 53-year-old woman presentedin the office for a full mouthreconstruction. Clinical and ra-diographic examination revealed

that none of the remaining teethwere salvageable.

It was decided to extract allthe remaining teeth and to placeimplant retained overdentures.

Four months after extraction,sinus augmentation was per-formed bilaterally and 6 ITI im-plants each were placed in themaxilla and the mandible.

After a healing period of 6months, implant retained over-dentures, using telescopic crownsas attachments, were delivered.The maxillary overdenture wasdesigned with a free palate(horseshoe-shape).

Case IV

A 62-year-old man presented foran implant-supported full mouthreconstruction. All remainingteeth had to be extracted and

provisional full dentures weredelivered.

Six months later, 2 ITI im-plants were placed in the maxilla,and 6 ITI implants were placed inthe mandible.

Five months later, a telescop-ic crown–supported, palate-freecomplete maxillary denture anda telescopic crown-supportedmandibular overdenture were de-livered.

Case V

A 52-year-old woman presentedfor periodontal treatment unda subsequent full mouth recon-struction.

Generalized radiographic hor-izontal bone loss was present inthe mandible reaching 50% of theroot length. The bone loss aroundteeth No. 18, 23, 26, and 31 ex-

FIGURE 1. Patient No. 6, before treatment. (a) Mandibular dentition. (b) Occlusal view of the maxilla.

FIGURE 2. Patient No. 6. (a) Mandible after extraction. (b) Socket augmented with bovine bone spongiosa. (c) Area covered witha resorbable membrane.



tended to the apices. Generalizedhorizontal bone loss was presentin the maxilla reaching 65% ofthe root length.

Probing depths ranged be-tween 6 and 9 mm. Teeth No. 18and 31 had clinical furcation in-volvement Class III.

All maxillary teeth presentedwith Class III mobility, spontane-ous bleeding, and gingival sensi-tivity upon touch.

The patient was diagnosedwith chronic periodontitis.

All maxillary teeth and teethNo. 18, 23, 26, and 31 were ex-tracted. The areas of teeth No. 20,21, 22, 27, 28, and 29 were treatedwith access periodontal surgery.A provisional maxillary denturewas delivered. Fixed partial den-tures were placed on teeth No. 20,21, 22, 27, 28, and 29.

A temporary complete den-ture was designed for the maxilla.Six months after extractions andperiodontal surgery, 4 ITI im-plants were placed in the mandi-ble, and 6 ITI implants wereplaced in the maxilla. The num-ber of implants was limited to 6since the patient preferred not toundergo sinus augmentations.

Six months after implant place-ment, an implant-supported horseshoe-shaped complete maxillarydenture with telescopic crowns asabutments was delivered. Ce-mented crowns were placed onthe mandibular implants.

Case VI

A 50-year-old man presented tothe practice reporting spontane-ous bleeding and mobility on allteeth.

Initial periodontal treatmentconsisting of scaling and rootplaning and oral hygiene instruc-tion had been performed 5 yearsearlier (March 1996). The patientdid not finish this treatmentphase and refused the suggestedsurgical treatment and support-ive periodontal therapy. He optedto return to his general dentist forfurther treatment.

Clinical examination showedseverely increased probing pock-et depth, bleeding and suppura-tion on probing, and mobility onall teeth (Figure 1a and b). Radio-graphic analysis revealed boneloss of more than 70% on all teeth.

The condition was diagnosedas a generalized severe periodon-titis (AAP Type IV).

All teeth of the remaining den-tition had a poor long-term prog-

FIGURES 5 AND 6. FIGURE 5. Patient No. 7, initial examination. (a) Frontal view. (b) Panoramic radiograph. FIGURE 6. Patient No. 7, afterimplant placement; final restorations and denture in place.

FIGURES 3 AND 4. FIGURE 3. Patient No. 6, mandible at re-entry. FIGURE 4. Patient No. 6, final restoration. (a) Telescopic crowns andsuperstructure try-on. (b) Telescopic crowns in place in the maxilla; prosthetic abutments placed in the mandible. (c) Panoramicradiograph with the metal frame in place; augmented areas outlined in yellow. (d) The final mandibular over-denture. (e)Overdentures in place.

TELESCOPIC CROWNS


nosis; therefore, it was decidedto extract all teeth.

The extractions were per-formed during the first treat-ment phase except for toothNo. 27. A cyst in that area wasremoved. Tooth No. 27 was keptto increase the retention of theprovisional denture and sched-uled for extraction later. Bonydefects were augmented withdemineralized bovine bone (Bi-oOss spongiosa, 0.25-1 mm, 0.25g; Geistlich Biomaterials) andcovered with a 25 3 25 mmresorbable bilayer membrane(Bio-Gide, Geistlich Biomateri-als) (Figure 2a through c).

An intermediate denture sup-ported by tooth No. 27 was de-livered. After 3 months, the areawas reopened (Figure 3) and 6 ITIimplants were inserted. At thesame time, tooth No. 27 wasextracted and the socket was pre-served.

Three months after insertion,the implants were uncovered andthe telescopic crowns and thefinal denture delivered.

To allow for the insertion ofimplants in the maxilla, a bilateralsinus-augmentation was per-formed. Seven months after aug-mentation, 8 ITI implants wereinserted.

Implant No. 8 was mobile 5weeks after placement and had tobe removed. The site was rinsedwith sterile saline solution andcovered with a 20 3 30 mmnonresorbable membrane (Cyto-plast Regentex GBR-200, Oral-tronics). The membrane wasremoved after 1 month.

A telescopic crown supportedfree palate (horseshoe-shaped)final overdenture was deliveredat the 9-month point (Figure 4athrough e).

Case VII

A 38-year-old woman presentedin the office for a regular dental

examination. Clinical evaluationrevealed severely increased prob-ing pocket depth. Radiographicsigns of horizontal and verticalbone loss up to two-thirds of theroot length were present (Figure5a and b). The maxillary molarshad Class III furcation involve-ment. All teeth in the maxilla hada poor prognosis.

The patient was informed ofthe etiology of her periodontalproblems.

The maxillary teeth were ex-tracted 2 weeks after the initialexamination and an intermediatedenture in the maxilla was de-livered during the same appoint-ment.

Oral hygiene instructions weregiven and prophylactic cleaningswere performed repeatedly for theremaining teeth until an adequatelevel of plaque control could beachieved.

Bilateral sinus augmentationwas performed 2 months after theextraction of the maxillary teeth.

At the 6-month point (ie, 4months after the sinus augmenta-tion), 7 ITI implants were insertedinto the maxilla.

The maxillary implants wereuncovered after a 3-month heal-ing period (ie, at the 9-monthpoint) and an implant-retained,free palate complete denture withtelescopic crowns as abutmentswas delivered (Figure 6).

DISCUSSION

Telescopic crowns have beenused successfully for several de-cades to connect dentures tonatural teeth.1–18

Advantages of their use areeasier accessibility to oral hygieneprocedures and the relative in-dependence of the individualattachments, which often allowsfor sufficient support of the den-ture even after single abutments

have failed.4–6,11,24 They also offera very high degree of retentionand a comparatively rigid con-nection to the abutments.25

A possible disadvantage of theuse of these attachments is thetechnically challenging and time-consuming process of fabricatingthem, resulting in comparativelyhigh costs for this type of treat-ment.25,27 Another disadvantagecan be the bulkiness of the crownsoften associated with their use,possibly leading to an unsatisfac-tory esthetic treatment outcome.This is usually only a problem ifteeth with a vital pulp are used asabutment teeth, thus limiting theamount of tooth substance thatcan be removed to allow sufficientspace for the crown and thecoping. In cases where implantsare used, the primary telescopeusually can be designed suffi-ciently small so as not to resultin an overly bulky superstructure.

A possible loss of retentionresulting from mechanical wearof the copings has been dis-cussed;27 despite the advantages,there are not many cases usingthese attachments on implantsreported in the literature.

The use of cemented, rigid-telescopic crowns has been sug-gested to avoid disadvantages ofscrew-retained superstructures,such as difficult access to thescrew, access holes on the occlusalsurface or in functional or estheti-cally unfavorable positions. Atthe same time, they still alloweasy removal of the superstruc-ture if necessary, thus combiningthe advantages of cementedcrowns with those of screw-re-tained ones. This approach mayalso be helpful in cases whereimproper implant position needsto be compensated.28–31

Another option is the use oftelescopic crowns with implant-supported overdentures. Al-though only limited data are



available on this type of treat-ment, the results so far indicatethat this treatment modality canlead to predictable long-termtreatment outcomes.25,32,33 In ad-dition to the above-mentionedadvantages of telescopic crowns,they also allow for more freedomin the placement of the implantscompared to bar attachmentssince there is no risk of reducingthe tongue-space.34 This can be anadvantage in cases where idealimplant position or inclinationcannot be achieved.

One has to differentiate be-tween the use of rigid and non-rigid telescopic crowns. Rigidtelescopic crowns have a definiteend position (ie, a rest on theabutment where the coping rests).Friction is low enough to allowfor easy removal of the over-denture but sufficiently high tominimize movement duringfunction. Nonrigid telescopiccrowns, also known as resilientcrowns, have no defined apicalend positions. They do allow fora certain amount of verticalmovement under load, thus dis-tributing forces to the mucosalrest areas.4

While rigid telescopic crownsallow for a higher stability of theoverdenture, the use of two im-plants in the interforaminal areamay not be advisable, since thedenture may act as a lever placingunnecessary high stress on theimplants, possibly leading totheir fracture.25 More clinicaldata are necessary to verify thesefindings.

Two implant, nonrigid tele-scopic dentures, on the otherhand, show a long-term treat-ment outcome comparable toother type of implant-supportedattachments.32

The existing data suggest thatimplant-supported telescopiccrowns can be a viable alternative

to the commonly used bar andball attachments.

No conclusive data on thecombined use of implants andnatural teeth to support fixed orremovable dentures exist so far.Both the successful use of thisapproach as well as the failureshave been reported with thepossible intrusion of the toothbeing one of the major problems,irrespective of the use of a rigid orflexible connection between thetooth and the implant.10,35–48 Theuse of telescopic crowns may bea treatment modality that allowsfor the successful combined useof natural teeth and implants tosupport dentures. At this pointa conclusion on the validity ofthis treatment approach cannotbe made, thus leaving the finaldecision on the judgment of theclinician.

The case treatments presentedin this report have been in func-tion for up to 4.5 years afterloading. During that time noadverse events were reported.

None of the patients have haddifficulties inserting or removingthe overdentures, nor has theretention decreased significantly.

The regular recall visits re-vealed no signs of inflammationof the tissues around the im-plants, indicating that the pa-tients had no problems incleaning the implants.

CONCLUSIONS

This case series demonstrates thatdental implants with telescopiccrowns may be used successfullyfor the support of removabledentures.

Further studies with a largernumber of cases are necessaryto validate these findings and toallow for final conclusions on thelong-term predictability of thistreatment approach.

NOTE

Straumann did not provide anyfinancial support for this study.

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Documents

Telescopic Crowns as Attachments for Implant Supported Restorations: A Case Series