Nine years long controversy :
          Semi-circular bridge with 6 pontics in frontal area of progenial 
           maxillae with condescend vertical dimension between jaws.

 

This is highly controversial but successful case that I encountered during my practice. It all began 9 years ago, when this patient walked  into our office, demanding bridge in his upper jaw. This case was took over by our head of the office- Dr.Velkoski, I was dental technician in that time.While, 9 years after case was lead by me as dentist and dental technician.

Intra-Oral status

General overview:
We found out that patient has progenia , and due to unexistence of posterior teeth, vertical dimension (distance between jaws) was too small.


Detailed inspection:

Dental Status in Maxillae: 

Teeth missing:
Frontal area: All frontal incisors (2,1-1,2), right canine (3)
Posterior right:  first premolar (4), first and second molar (6,7)
Posterior left: edentulous:all molars (6,7,8)
Teeth present:
Left: Canine (3) and two premolars (4,5)
Right: Second premolar (5) and third molar (8)

Periodontal status :
Status of left canine : short clinical crown: only 4 millimeters,and frontal recessions of gingiva. No lateral movement on palpation, or pain upon percution.

 

Dental Status in Mandible:

All premolars and molars missing from both sides , except 5-th right
(second right premolar) .

 

Occlusal analysis

Condescend  byte distance (vertical dimension)
Due to loss of posterior teeth from both sides of mandible, and loss of some molars in upper posterior area, byte distance became condescend by time.With anamnesys we found out that loss of these "byte-important" teeth occurred in teen-ages, and since patient was 35, it took over 15 years of time to come to this stage when distance between left upper premolars (see photo) and lower alveolar ridge was only 3 millimeters. If we kept this distance, we couldn`t do any prosthesis in posterior area. We had to rise vertical dimension with a bridge.



    




Progenial correlation between jaws

Since his birth, patient had progenial jaw correlation. There was inverse over-byte status of his frontal teeth ( lower front teeth overlap the upper front teeth by more than five millimeters when closing mouth..) -this situation cause slight protrusion of lower incisors. During his 30's.patient lost all of his upper incisors.                                                              

Proposed therapy in maxillae
In this situation , proposed solutions were:

1. Partial denture with metal base ( reduced palatinal surface) or
2. Circular bridgework from one to another end

In both cases , we would rise byte distance, and frontal teeth (of the bridge or denture) will be in slight protrusion in order to reach incisal margins of lower incisors , and to create tooth to tooth ( teete a teete) situation.
Patient`s demands
Patient wasn`t ready for use of partial denture ( psychological effect) , he was too young for it . He refused circular bridge, due to his fear that his "only functional teeth" ( his left two premolars) will decay under bridge. He was strict in demands for fixed prosthetic restoration, but without left premolars in it . That drove us in very delicate and specific situation.

Accepted therapy

Regarding patients demands, we came to only solution that was very controversial: bridgework with three retainers (one on short abutment) , and two pontics:  frontal with 6 components and posterior with 2 components. Problematic parts of this bridgework were
1. Left third canine that was too short for abutment
In their article "TOOTH PREPARATION FOR METAL CERAMIC RESTORATION" published in "Makedonski Stomatoloski Pregled" ( Issue no.1-4, Volume XXIV, 2000), Dr.Bajevska and Dr.Mirchev emphisized that :"At too short abutments basic line is longer than hypothenuse and crown rotation around centre of abutment is possible." So , this statement could implicate complications at short abutments like in this case . But, I must add that this rotation is possible only of we do single crown .Inclination of crown from its short abutment is possible when we have bridge that consists two abutments. In situations when we have bridge with 3 or more abutments , rotation or inclination over short abutment ( like one from this case study) is not possible, because two other abutments with sufficient hight are witholders of any malfunctonal movement of the third one.
2. Frontal pontic with 6 components.
Scientific thesis say that frontal pontic can be build of at most 4 elements(all frontal teeth), if abutments are both canines in good condition.But, this case was beyond these thesis. We decided to took that risk creating this bridge , and of course we mentioned to the patient that this bridge can cause loss of these 3 abutments, or provoke pathologic processes in oral mucosa of frontal edentulous ridge due to larger occlusal forces that this 6 component pontic will transfer from abutments to the ridge. To avoid this situation as much as we could , we decided to create only linear touch-point between frontal pontic and ridge. Because it was his strict demand, patient accepted to take responsibility of any collateral damages that could occur in future, and was aware that if this coud not succeed, the only solution would be partial removable denture.      

 


Bridge construction - highlights-

  • Occlusal and palatinal surfaces of the bridge were made of metal.We avoid application of composite because we expected hard masticatory   forces on frontal area that composite wouldn`t sustain.
  • Frontal pontic with 6 components
  • Linear touch-point surface between frontal pontic and ridge
  • Larger connection point between premolar and canine retainers and frontal pontic

  • Slight rising of vertical dimension between two jaws ( from 5 to 10 millimeters)



   

  • Slight protrusion on incisal components of frontal pontic in order to achieve teeth on teeth status 

Duration of the construction:
This bridge was installed in patients mouth in 1993, and succeed to survive until spring 2002 when patient visited our office to check up his bridge. With intra-oral inspection I found out small fissure (narrow opening) on the oclusal part , on the connection between left third  canine ( abutment) and frontal pontic. Bridge was still fixed in its base, there wasn`t any movement or extra vibration of the construction.Patient only noticed with his tongue that there is "some discontinuity on the surface of the bridge". I decided that after 9 year this bridge has done his job, and it was time to be pulled out.
For my surprise, parodontal status was excellent! There wasn`t any discolorations or processes in the mucosa of frontal edentulous ridge and those 3 abutments were in excellent shape.
Again , I proposed e new therapy with partial removable denture, but patient , again , like 9 years ago refused, and demanded the same bridge construction. New construction was made, and now all we can do is to wait how long this second bridge will survive :)



author : Boban Fidanoski
             Dental Office "Duki-Lek"
             Titovouzicka Str. No.10
              Skopje, Macedonia

          e-mail :   bobanfidanoski@yahoo.com

Date of on-line publishing: June 07-th , 2002

 

Note: Digital Camera used for this case: MUSTEK Smartpix. I apologize for lack of intra-oral images, because this camera was flash-less, and it was impossible to get intra-oral images.Images also has small resolution due to capacity of this camera. This camera was my only choice at that time, so in order to make record of this controversial case , I had to use this camera.